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VITAMINE C SERUM

VITAMINE C SERUM INGREDIENTS RESEARCHES

 

Purified Water

Free radical scavenging activity of a novel antioxidative peptide purified from hydrolysate of bullfrog skin, Rana catesbeiana Shaw

Abstract

In the present study, a peptide having antioxidant properties was isolated from bullfrog skin protein, Rana catesbeiana Shaw. Bullfrog skin protein was hydrolyzed using alcalase, neutrase, pepsin, papain, α-chymotrypsin and trypsin. Antioxidant activities of respective hydrolysates were evaluated using lipid peroxidation inhibition assay and direct free radical scavenging activity by using electron spin resonance (ESR) spectrometer. Among hydrolysates, alcalase derived hydrolysate exhibited the highest antioxidant activities than those of other enzyme hydrolysates. In order to purity a peptide having potent antioxidant properties, alcalase hydrolysate was separated using consecutive chromatographic methods on a Hiprep 16/10 DEAE FF anion exchange column, Superdex Peptide 10/300 GL gel filtration column and highan octadecylsilane (ODS) C18 reversed phase column. Finally, a potent antioxidative peptide was isolated and its sequence was identified to be LEELEEELEGCE (1487 Da) by Q-TOF ESI mass spectroscopy. This antioxidant peptide from bullfrog skin protein (APBSP) inhibited lipid peroxidation higher than that of α-tocopherol as positive control and efficiently quenched different sources of free radicals: DPPH radical (IC50 = 16.1 μM), hydroxyl radical (IC50 = 12.8 μM), superoxide radical (IC50 = 34.0 μM) and peroxyl radical (IC50 = 32.6 μM). Moreover, MTT assay showed that this peptide does not exert any cytotoxicity on human embryonic lung fibroblasts cell line (MRC-5).

Zhong-Ji Qian,Won-Kyo Jung,Se-Kwon Kim.Bioresource Technology. Volume 99, Issue 6, April 2008, Pages 1690–1698.doi:10.1016/j.biortech.2007.04.005

 

Rapid enumeration of physiologically active bacteria in purified water used in the pharmaceutical manufacturing process

Abstract

Physiologically active bacteria in purified water used in the manufacturing process of pharmaceutical products were enumerated in situ. Bacteria with growth potential were enumerated using the micro-colony technique and direct viable counting (DVC), followed by 24 h of incubation in 100-fold diluted SCDB (Soybean Casein Digest Broth) at 30 °C. Respiring and esterase-active bacteria were detected by fluorescent staining with 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) and 6-carboxyfluorescein diacetate (6CFDA), respectively. A large number of bacteria in purified water retained physiological activity, while most could not form colonies on conventional media. The techniques applied in this study enabled bacteria to be counted within 24 h so results could be available within one working day. These rapid and convenient techniques should be useful for the systematic monitoring of bacteria in water used for pharmaceutical manufacturing.

Kawai,N. Yamaguchi andM. Nasu.Journal of Applied Microbiology.Volume 86, Issue 3, pages 496–504, March 1999. DOI: 10.1046/j.1365-2672.1999.00689.x

http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2672.1999.00689.x/full

 

Glycerine

Instrumental and dermatologist evaluation of the effect of glycerine and urea on dry skin in atopic dermatitis

Abstract

Background/aims: Moisturising creams are useful treatment adjuncts in inflammatory dermatoses and have beneficial effects in the treatment of dry, scaly skin. The effects on dryness and skin permeability of a new moisturising cream with 20% glycerine was compared with its placebo and with a medicinally authorised cream with 4% urea (combined with 4% sodium chloride) in the treatment of dry skin.

Loden, M., et al. “Instrumental and dermatologist evaluation of the effect of glycerine and urea on dry skin in atopic dermatitis.” Skin research and technology 7.4 (2001): 209-213.

Glycerine: A Natural Ingredient for Moisturizing Skin

Glycerine is one of the best natural moisturizers in living systems and has been used in skin

care products for preventing and treating skin dryness because it moisturizes/plasticizes the

stratum corneum (SC).

Orth, Donald S., and Yohini Appa. “1 8 Glycerine: A Natural Ingredient for Moisturizing Skin.” Dry skin and moisturizers: chemistry and function 2 (1999): 213.

Skin moisturisation and elasticity originate from at least two different mechanisms

Skin moisturisation and elasticity are clearly linked in people’s mind. For a large series of neat personal care ingredients we measured both their skin moisturising and plasticising performance on human skin in‐vivo, and were able to rank the products according to their effectiveness. Efficacy was expressed relative to benchmark products: glycerine for moisturisation and water for elasticity. A good spread in skin moisturisation efficacy was found: 15 of our products had a relative performance of less than 30%, 23 products scored between 30 and 70% and 7 ingredients marked above 70%. For skin elasticity, the number of products in the corresponding groups was 36, 4 and 2. This discrepancy could be due to the choice of benchmark products, but when the values for relative elasticity performance of the various ingredients were plotted against those of relative moisturisation effectiveness, it became obvious that skin moisturisation and elasticity are not linearly correlated. This is at least remarkable as water was used as the benchmark product for skin elasticity. The common belief that increased skin moisturisation will automatically lead to enhanced skin elasticity is therefore unlikely to be true.

The only logical conclusion seems to be that different molecular and/or biochemical mechanisms are contributing to these two skin functionalities. By means of Principal Component Analysis, the correlation between molecular descriptors such as skin penetration and humectancy on the one hand and substantivity and occlusivity on the other was evaluated to explain the observed skin moisturisation. It became obvious that none of these purely molecule‐based molecular descriptors could explain the measured skin effects. Skin itself plays an important role in a yet unidentified manner. If both activities are desired in one cosmetic formulation, at least two active ingredients will need to be incorporated, each contributing to one of the two effects.

Examples of multifunctional mixtures and an assessment of the feasibility of obtaining multifunctional molecules are presented.

Wiechers, J. M., and Tony Barlow. “Skin moisturisation and elasticity originate from at least two different mechanisms.” International journal of cosmetic science 21.6 (1999): 425-435.

 

Paraffinum Liquidum

Effect of different moisturizers on SLS‐irritated human skin

Moisturizers are widely used to treat irritant contact dermatitis (ICD). Their use is, however, not well‐documented and standardized models for testing skin care products are needed to acquire documentation of their efficacy. The present study was undertaken to evaluate the effect of 6 commonly‐used moisturizers on the recovery of irritated human skin. No commercial interests were involved in the study. 36 healthy volunteers had patch tests with SLS 0.5% applied on their forearms/upper arms for 24 h. After irritation of the skin, all volunteers had a moisturizer applied on one forearm/upper arm, respectively, 3 × daily for the following 5 days. The other forearm/upper arm served as an untreated control. Each moisturizer was tested on 12 volunteers and each volunteer tested 2 moisturizers at the same time. Evaluation was done on days 1, 3 and 8 by transepidermal water loss, electrical capacitance, laser Doppler flowmetry, DermaSpectrometry and clinical scoring. All 6 moisturizers were found to accelerate regeneration of the skin barrier function when compared to irritated non‐treated skin. The most lipid‐rich moisturizers improved barrier restoration more rapidly than the less lipid‐rich moisturizers. We suggest this experimental model for further moisturizer efficacy testing.

Held, Elisabeth, Henrik Lund, and Tove Agner. “Effect of different moisturizers on SLS‐irritated human skin.” Contact dermatitis 44.4 (2001): 229-234.

 

A double-blind study comparing the effect of glycerin and urea on dry, eczematous skin in atopic patients

Abstract

Moisturizing creams have beneficial effects in the treatment of dry, scaly skin, but they may induce adverse skin reactions. In a randomized double-blind study, 197 patients with atopic dermatitis were treated with one of the following: a new moisturizing cream with 20% glycerin, its cream base without glycerin as placebo, or a cream with 4% urea and 4% sodium chloride. The patients were asked to apply the cream at least once daily for 30 days. Adverse skin reactions and changes in skin dryness were assessed by the patient and a dermatologist. Adverse skin reactions such as smarting (a sharp local superficial sensation) were felt significantly less among patients using the 20% glycerin cream compared with the urea-saline cream, because 10% of the patients judged the smarting as severe or moderate when using glycerin cream, whereas 24% did so using urea-saline cream (p < 0.0006). No differences were found regarding skin reactions such as stinging, itching and dryness/irritation. The study showed equal effects on skin dryness as judged by the patients and the dermatologist. In conclusion, a glycerin containing cream appears to be a suitable alternative to urea/sodium chloride in the treatment of atopic dry skin.

Lodén, Marie, et al. “A double-blind study comparing the effect of glycerin and urea on dry, eczematous skin in atopic patients.” Acta Dermato Venereologica 82.1 (2002): 45-47.

 

Cetanol

 

Skin-treating composition and vehicle for skin-treating agents

Abstract

The present invention relates to a skin-treating composition comprising an aqueous phase in which urea and lactic acid are dissolved. Optionally, the composition of the invention may comprise a lipid phase, wetting or emulsifying agents and amino acids. The composition is per se beneficial for the treatment of certain abnormal skin conditions; it is also an excellent vehicle for therapeutically active drugs for the treatment of pathological skin conditions.

Swanbeck, Gunnar PE. “Skin-treating composition and vehicle for skin-treating agents.” U.S. Patent No. 3,666,863. 30 May 1972.

 

Evaluation of controlled-release polar lipid microparticles

Abstract

The aim of the present study was to prepare controlled-release tablets of poorly-soluble drug, felodipine, and various erodable lipophilic excipients. Spray chilling was used to formulate the drug and the excipients into solid dispersion microparticles, which were then compressed. The microparticles were characterised by Fourier transform infrared spectroscopy, hot-stage microscopy, scanning electron microscopy, and image analysis. The amine and the carbonyl groups of felodipine formed hydrogen bonds with the carriers. The shape of the particles was spherical with the median particle diameter ranging from 25 to 35 μm. Surprisingly, the degree of crystallinity in felodipine and the ease of tablet disintegration played a more significant role on the felodipine dissolution rate than the matrix lipophilicity. Felodipine release rate was slowest from the least lipophilic tablets.

Savolainen, Marja, et al. “Evaluation of controlled-release polar lipid microparticles.” International journal of pharmaceutics 244.1-2 (2002): 151-161.

 

Method for preparing preparations having controlled release of an active component

Abstract

A method of preparing a preparation made up by bodies comprising an active component in decreasing concentration towards the surface of the bodies. The method comprises coating a particle with a composition comprising the active component in a continuous coating operation whereby the concentration of the active component is decreased. The active component may be a drug, a pesticide or an agent having some other effect.

Bogentoft, Conny B., and Curt H. Appelgren. “Method for preparing preparations having controlled release of an active component.” U.S. Patent No. 4,289,795. 15 Sep. 1981.

 

High incidence of contact dermatitis in leg-ulcer patients–implications for management

Abstract

A retrospective review of patch test results from all new patients with venous leg ulcers was performed for the preceding 11 months. Eighty one patients referred from general practitioners and district nurses with venous stasis ulcers were included. Positive patch tests were found in 54 patients (67%), including a continued high incidence of allergy to lanolin and topical antibiotics. Multiple allergies were found in 48 patients (58%). In addition, a new problem of allergy to cetearyl alcohol, a constituent of commonly used creams and paste bandages, was identified in 13 patients. There is a continuing high incidence of contact sensitivity in patients with venous stasis ulcers which has important implications for the management of these patients.

Wilson, C. L., et al. “High incidence of contact dermatitis in leg‐ulcer patients–implications for management.” Clinical and experimental dermatology 16.4 (1991): 250-253. DOI: 10.1111/j.1365-2230.1991.tb00368.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2230.1991.tb00368.x/abstract

 

Liquid skin treatment

ABSTRACT

A composition for the maintenance of smooth, radiant, hydrated skin, including sufficient amounts of acids of hydroxyacid, to facilitate exfoliation of skin in a novel manner, without substantial irritation, as well as the prevention, treatment and management of skin conditions, such as acne, wrinkled, irregularly pigmented, photoaged, and thickened layers of the epidermis, and the like, which has as its constituents, safflower oil, flaxseed oil, sweet almond oil, apricot kernel oil, jojoba oil, organic beeswax, stearic acid, cetearyl alcohol, cocoa butter, vitamin A and tocopheral linoleate, borax, oil of lavender, and tincture of benzoin as an antimicrobial agent.

Harbeck, Marie. “Nonirritating exfoliation for radiant, hydrated skin including safflower oil, flaxseed oil, beeswax, glycol stearate, cetearyl alcohol, cocoa butter, vitamin a, tocopheral linoleate, essential oils, and tincture of benzoin.” U.S. Patent Application No. 09/753,901.

https://www.google.com/patents/US20010001666

 

Distribution of sunscreens on skin

Abstract

The effectiveness of sunscreens was originally achieved by incorporation of soluble organic UV absorbers such as cinnamates and others into cosmetic formulations. Determinations of the sun protection factor (SPF) of emulsions containing different organic UV absorbers clearly indicate that the efficacy depends on the absorption characteristics of each single UV filter substance. Nowadays, micronised pigments such as titanium dioxide or zinc oxide have also been found to be protective against harmful UV rays. Our investigations using optical and electron microscopy proved that neither surface characteristics, particle size nor shape of the micronised pigments result in any dermal absorption of this substance. Micronised titanium dioxide is solely deposited on the outermost surface of the stratum corneum and cannot be detected in deeper stratum corneum layers, the human epidermis and dermis.

Schulz, Jens, et al. “Distribution of sunscreens on skin.” Advanced drug delivery reviews 54 (2002): S157-S163. doi:10.1016/S0169-409X(02)00120-5

http://www.sciencedirect.com/science/article/pii/S0169409X02001205

 

Topical formulations and transdermal delivery systems containing 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine

ABSTRACT

Pharmaceutical formulations and adhesive-coated sheet materials for the topical and/or transdermal delivery of 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine, including creams, ointments and pressure-sensitive adhesive compositions. Pharmacological methods of using the formulations and the adhesive-coated sheet materials of the invention in the treatment of viral infections.

Wick, Steven M., et al. “Viricides comprising isotearic acid; skin disorders.” U.S. Patent No. 5,238,944. 24 Aug. 1993.

https://www.google.com/patents/US5238944

 

Foam skin cream, uses of the foam skin protection cream and a process for its preparation

ABSTRACT

A foam skin cream can be obtained by

preparing a phase I by melting at 75° C. a mixture containing fatty acids, especially C12-C22 fatty acids, optionally unsaturated and/or polyunsaturated fatty acids, emulsifiers, coemulsifiers, such as triceteareth-4-phosphate, followed by metering it with stirring to

a phase II temperature-controlled at 75° C. obtained from an aqueous mixture containing moisturizers, such as propylene glycol and/or polyhydric alcohols, especially glycerol, emulsifiers, such as alkyl sarcosinates, and skin care additives, such as allantoin;

wherein homogeneous mixing of phases I and II is provided and said metering is performed at a temperature of 75° C.;

after the metered addition, the temperature is maintained at 75° C. for a period of between 5 and 20 minutes; whereupon

the temperature of the thus obtained mixture is lowered to a temperature of between 30 and 40° C. with constant stirring;

the pH value is adjusted to from 7.6 to 8.2, preferably with a skin-compatible basic organic compound, and the mixture obtained is filled into dosage forms with the addition of a propellant.

Neubourg, Fritz. “Foam skin cream, uses of the foam skin protection cream and a process for its preparation.” U.S. Patent No. 6,423,323. 23 Jul. 2002.

https://www.google.com/patents/US6423323

 

Stearic Acid

 

Structure/Effect Studies of Fatty Acid Isomers as Skin Penetration Enhancers and Skin Irritants

Abstract

Comparisons were made of branched vs unbranched saturated fatty acids and cis vs trans unsaturated fatty acids as skin penetration enhancers and primary skin irritants. Skin penetration studies used naloxone base as the diffusant, propylene glycol as the vehicle, and human skin. Maximum naloxone flux was with C9–12-branched and unbranched fatty acids. For C5–14 fatty acids, branched and unbranched isomers had similar effects. One branched C18 fatty acid isomer (C16-branched isostearic acid) was more effective in enhancing skin penetration than a differently branched (C2-branched isostearic acid) or unbranched C18 isomer (stearic acid). There was no significant difference between cis and trans unsaturated C16–18 fatty acid isomers in their effects on naloxone flux, and all unsaturated fatty acids were more effective enhancers than the corresponding saturated isomers. Several of these fatty acid/propylene glycol vehicles were evaluated in a rabbit primary skin irritation test. Irritation indices were poorly correlated with the effectiveness of the vehicles in enhancing naloxone flux. It was possible to enhance naloxone skin penetration greatly with a vehicle with only minimal skin irritation potential.

Aungst, Bruce J. “Structure/effect studies of fatty acid isomers as skin penetration enhancers and skin irritants.” Pharmaceutical research 6.3 (1989): 244-247. DOI 10.1023/A:1015921702258

http://link.springer.com/article/10.1023/A:1015921702258

 

A comparative study of stearic and lignoceric acid oxidation by human skin fibroblasts

Abstract

Sensitive assays were developed for long chain and very long chain fatty acid oxidation in human skin fibroblast homogenates. Stearic and lignoceric acids were degraded by the fibroblasts by the β-oxidation pathway. The cofactor requirements for stearic and lignoceric acid β-oxidation were very similar but not identical. For example, appreciable lignoceric acid oxidation could be demonstrated only in the presence of α-cyclodextrin and was inhibited by Triton X-100. In Zellweger’s syndrome, stearic acid β-oxidation was partially reduced whereas lignoceric acid β-oxidation was reduced dramatically (< 12% activity compared to the controls). The results presented suggest that stearic acid β-oxidation occurs in mitochondria as well as in peroxisomes, but lignoceric acid oxidation occurs entirely in the peroxisomes. We suggest that the β-oxidation systems for stearic acid and lignoceric acid may be different.

Singh, Harmeet, and Alf Poulos. “A comparative study of stearic and lignoceric acid oxidation by human skin fibroblasts.” Archives of biochemistry and biophysics 250.1 (1986): 171-179. doi:10.1016/0003-9861(86)90714-9

http://www.sciencedirect.com/science/article/pii/0003986186907149

 

The contact angle of water on viable human skin

Abstract

The contact angle of water was measured on clean dry skin and on skin coated with the following materials: paraffin, stearic acid, a lanolin derivative, a quaternary ammonium salt, and hydrophilic and hydrophobic silicones. The area of skin tested was the upper surface of the index finger, which was positioned on the stage of a contact angle telescope goniometer. Clean and degreased skin gave a high contact angle with water (> 100°). All agents studied reduced the water droplet contact angle when applied to the skin. Reductions of contact angles were observed at very low levels of application. Unexpected results were obtained with stearic acid. The water droplet contact angle reduced to a minimum of 70° at 100 μgm stearic acid/cm2 on skin, but further application of stearic acid yielded increasing contact angles to levels from 105° to 120°, depending upon the subject tested.

Ginn, M. E., C. M. Noyes, and Eric Jungermann. “The contact angle of water on viable human skin.” Journal of colloid and interface science 26.2 (1968): 146-151. doi:10.1016/0021-9797(68)90306-8

http://www.sciencedirect.com/science/article/pii/0021979768903068

 

Increased Synthesis of Hexacosanoic Acid (C26 :0) by Cultured Skin Fibroblasts from Patients with Adrenoleukodystrophy (ALD) and Adrenomyeloneuropathy (AMN)1

Abstract

We studied the metabolism of radioactive stearic acid by cultured skin fibroblasts from patients with adrenoleukodystrophy (ALD) and its variant, adrenomyeloneuropathy (AMN), to clarify the mechanism of the increased content of very long chain saturated fatty acids in cholesterol esters and sphirigolipids, which are known to be the characteristic biochemical changes in ALD and AMN. A substantial amount of hexacosanoic acid (C26 : 0) was synthesized from stearic acid by ALD and AMN fibroblasts, whereas only a trace amount of hexacosanoic acid was synthesized by control fibroblasts. This indicates that the primary biochemical defect in ALD and AMN may involve the elongation system of very long chain fatty acids.

Tsuji, Shoji, et al. “Increased synthesis of hexacosanoic acid (C26: 0) by cultured skin fibroblasts from patients with adrenoleukodystrophy (ALD) and adrenomyeloneuropathy (AMN).” Journal of biochemistry 90.4 (1981): 1233-1236.

http://jb.oxfordjournals.org/content/90/4/1233.short

 

An electron spin resonance study of skin penetration enhancers

Abstract

The structured intercellular lipids of the stratum corneum are thought to play an important role in controlling the transport of drugs across the skin. In this study, multilamellar dipalmitoylphosphatidylcholine liposomes were used as a model of structured lipids. The effect of temperature and skin penetration enhancers on the lipid bilayer, was assessed using a spin labelling technique, in which 5-doxyl stearic acid was incorporated into the bilayer. The order parameter (S) of the spin label was calculated from the observed spectra. An increase in temperature decreased the order parameter. This decrease is due to increased rotational movement of the acyl chain of the spin label about its long molecular axis. It indicates a decrease in order within the bilayer structure, as a result of increased flexibility of the lipid molecules. Known skin penetration enhancers, Brij 36T, n-decylmethyl sulphoxide and oleic acid, also decreased the order parameter of the spin label. The penetration enhancer N-methyl-2-pyrrolidone had no significant effect. The results obtained were confirmed using a light scattering technique, in which the phase transition temperature of the liposomes was monitored in the presence and absence of the enhancers. 5-Doxyl stearic acid was incorporated into stratum corneum, separated from human cadaver skin. The spectra obtained were similar to those of the liposomal samples and the application of n-decylmethyl sulphoxide had a similar effect on the order parameter.

 

Cosmetic preparation

ABSTRACT

A cosmetic preparation is disclosed which is effective in moisturizing and softening skin, improving texture and feel of skin, and diminishing superficial and deep wrinkles in skin. The preparation comprises gibberellic acid and lysine as active ingredients. The preparation can contain as additional active ingredients gliadin, ascorbic acid and urea.

Parkinson, Richard W. “Gibberellic acid, lysine, skin softener.” U.S. Patent No. 4,518,614. 21 May 1985.

https://www.google.com/patents/US4518614

 

Cleansing without compromise: the impact of cleansers on the skin barrier and the technology of mild cleansing

ABSTRACT:

Cleanser technology has come a long way from merely cleansing to providing mildness and moisturizing benefits as well. It is known that harsh surfactants in cleansers can cause damage to skin proteins and lipids, leading to after-wash tightness, dryness, barrier damage, irritation, and even itch. In order for cleansers to provide skin-care benefits, they first must minimize surfactant damage to skin proteins and lipids. Secondly, they must deposit and deliver beneficial agents such as occlusives, skin lipids, and humectants under wash conditions to improve skin hydration, as well as mechanical and visual properties. While all surfactants tend to interact to some degree with lipids, their interaction with proteins can vary significantly, depending upon the nature of their functional head group. In vitro, ex vivo, and in vivo studies have shown that surfactants that cause significant skin irritation interact strongly with skin proteins. Based on this understanding, several surfactants and surfactant mixtures have been identified as “less irritating” mild surfactants because of their diminished interactions with skin proteins. Surfactants that interact minimally with both skin lipids and proteins are especially mild. Another factor that can aggravate surfactant-induced dryness and irritation is the pH of the cleanser. The present authors’ recent studies demonstrate that high pH (pH 10) solutions, even in the absence of surfactants, can increase stratum corneum (SC) swelling and alter lipid rigidity, thereby suggesting that cleansers with neutral or acidic pH, close to SC-normal pH 5.5, may be potentially less damaging to the skin. Mildness enhancers and moisturizing agents such as lipids, occlusives, and humectants minimize damaging interactions between surfactants, and skin proteins and lipids, and thereby, reduce skin damage. In addition, these agents play an ameliorative role, replenishing the skin lipids lost during the wash period. The present review discusses the benefits of such agents and their respective roles in improving the overall health of the skin barrier.

 

Dietary trans fatty acids increase conjugated linoleic acid levels in human serum

Abstract

Conjugated linoleic acid (CLA), fatty acids with 18 carbon atoms and two conjugated cis/trans double bonds, have shown anticarcinogenic effects in experimental studies. We determined the proportion of CLA (the sum of cis-9, trans-11 and trans-9, cis-11 CLA) of total fatty acids in the diets and serum samples of healthy subjects who consumed for 5 weeks a diet high in saturated fatty acids mainly from dairy fat, followed by 5 weeks on a diet high (8.7% of energy, en%) in trans fatty acids from partially hydrogenated vegetable oil (40 subjects) or a similar diet high in stearic acid (9.3 en%, 40 subjects). All diets contained equal amounts of fat and cis-monounsaturated and cis-polyunsaturated fatty acids. The fatty acid compositions of the pooled diets and fasting serum samples drawn at the end of the diet periods were analyzed by gas chromatography, and CLA was identified by comparison with a standard of C18:2 conjugated dienes. The proportions of CLA in the dairy fat, trans fatty acid, and stearic acid diets were 0.37, 0.04, and 0.10% of total methylated fatty acids, respectively. The corresponding mean (SD) proportions in serum were 0.33 (0.07)% after the dairy fat diet, higher, 0.43 (0.12)%, P < 0.001, after the trans fatty acid diet, and lower, 0.17 (0.06)%, P < 0.001, after the stearic acid diet. The difference between dairy fat and stearic acid diets was explained by different dietary intakes but increased amounts of CLA not present in the diet were incorporated into serum lipids during the trans fatty acid diet. CLA in human tissues is partly derived from the diet but part of it may be formed by conversion from dietary trans fatty acids.

Salminen, Irma, et al. “Dietary trans fatty acids increase conjugated linoleic acid levels in human serum.” The Journal of Nutritional Biochemistry 9.2 (1998): 93-98. doi:10.1016/S0955-2863(97)00173-3

http://www.sciencedirect.com/science/article/pii/S0955286397001733

 

Conversions of palmitic and stearic acid in the intact rat

Abstract

  1. A smaller portion of labeled palmitic acid is desaturated to palmitoleic acid, but comparable amounts of label are also found in stearic and octadecenoic acid.
  2. The liver octadecenoic acid label derived from palmitic acid is found mainly in oleic acid, but particularly in the phospholipids an appreciable fraction is found in cis-vaccenic acid. Liver phospholipids also contain more unlabeled cis-vaccenic acid than do liver neutral fat and adipose tissue total fat.
  3. In extrahepatic tissues, including subcutaneous adipose tissue, desaturation and elongation are less prominent than in liver.
  4. Fasting abolishes desaturation of both stearic and palmitic acid completely and elongation of palmitic acid almost completely.
  5. In the tissues fatty acids appear to be metabolized in the same manner, whether they be formed in situ by conversion of other acids or are taken up as such from the blood.

Elovson, J. “Conversions of palmitic and stearic acid in the intact rat.” Biochimica et Biophysica Acta (BBA)-Lipids and Lipid Metabolism 106.2 (1965): 291-303. doi:10.1016/0005-2760(65)90037-8

http://www.sciencedirect.com/science/article/pii/0005276065900378

 

A comparative study of straight chain and branched chain fatty acid oxidation in skin fibroblasts from patients with peroxisomal disorders.

ABSTRACT

The beta-oxidation of stearic acid and of alpha- and gamma-methyl isoprenoid-derived fatty acids (pristanic and tetramethylheptadecanoic acids, respectively) was investigated in normal skin fibroblasts and in fibroblasts from patients with inherited defects in peroxisomal biogenesis. Stearic acid beta-oxidation by normal fibroblast homogenates was several-fold greater compared to the oxidation of the two branched chain fatty acids. The effect of phosphatidylcholine, alpha-cyclodextrin, and bovine serum albumin on the three activities suggests that different enzymes are involved in the beta-oxidation of straight chain and branched chain fatty acids. Homogenates of fibroblasts from patients with a deficiency in peroxisomes (Zellweger syndrome and infantile Refsum’s disease) showed a normal ability to beta-oxidize stearic acid, but the oxidation of pristanic and tetramethylheptadecanoic acid was decreased. Concomitantly, 14CO2 production from the branched chain fatty acids by Zellweger fibroblasts in culture (but not from stearic acid) was greatly diminished. The Zellweger fibroblasts also showed a marked reduction in the amount of water-soluble metabolites from the radiolabeled branched chain fatty acids that are released into the culture medium. The data presented indicate that the oxidation of alpha- and gamma-methyl isoprenoid-derived fatty acids takes place largely in peroxisomes in human skin fibroblasts.

Singh, Harmeet, et al. “A comparative study of straight chain and branched chain fatty acid oxidation in skin fibroblasts from patients with peroxisomal disorders.” Journal of lipid research 31.2 (1990): 217-225.

http://www.jlr.org/content/31/2/217.short

 

Ceteareth-20

 

Composition for skin care and protection

ABSTRACT

A composition for topical application to the skin of a human being is disclosed which provides a barrier against irritation and painful damage due to contact with many otherwise harmful materials. The composition comprises in combination water, dimethicone, stearic acid, coconut fatty acid, isopropyl myristate, glycerin, triethanolamine, cetyl alcohol, polyvinyl pyrrolidone, cetearyl alcohol, ceteareth-20, tetrasodium EDTA, hydroxyethyl cellulose, aloe vera gel, vitamin E and lanolin.

Klein, Kenneth. “Composition for skin care and protection.” U.S. Patent No. 5,208,013. 4 May 1993.

https://www.google.com/patents/US5208013

 

Rheological behavior and the SPF of sunscreens

Abstract

Due to a large variety of sunscreens, it is important to study among other things, the effect of the vehicle on the thickness and uniformity of sunscreen films. In this study, we determined the physical stability of five sunscreens SPF 15 (FA to FG), containing or not PVP/eicosene crosspolymer (PVP/EC), and two different self-emulsifying bases (SEB), and also evaluated the influence of the vehicle in their SPF. In the study of physical stability, formulations were stored at 25, 37 and 45 °C, for 28 days. Viscosity and rheological behavior of the formulations were determined using a Brookfield rheometer. Investigations of the SPF were carried out in a group of 30 volunteers (COLIPA methodology). The FC samples (phosphate-based SEB), with a lower thixotropy, showed statistically higher SPF (13.6) when compared with FB (non-ionic SEB), which presented higher thixotropy and a SPF of 9.84. The FE sample (phosphate-based SEB+PVP/EC) presented the same SPF as the FC, but had a higher thixotropy. The FB formulation (stable with higher thixotropy) showed the lowest SPF while FC (an unstable formulation with lower thixotropy) presented a higher SPF. We concluded that FE was the best formulation showing a higher SPF and stability and the study of rheology can help the development of sunscreens.

Gaspar, L. R., and PMBG Maia Campos. “Rheological behavior and the SPF of sunscreens.” International journal of pharmaceutics 250.1 (2003): 35-44.

 

Stable cream and lotion bases for lipophilic drug compositions

Abstract

A cosmetically elegant, physically and chemically stable base in the form of an oil-in-water emulsion for use in cream and lotion lipophilic drug containing- pharmaceutical compositions containing at least one lipophilic drug and an effective amount of N-methyl-2-pyrrolidone is disclosed.

Munayyer, Farah J., and Joel A. Sequeira. “Stable cream and lotion bases for lipophilic drug compositions.” U.S. Patent No. 5,422,361. 6 Jun. 1995.

 

Skin whitening composition

Abstract

Cosmetic skin whitening compositions based on the combination of plant extracts and alpha-, beta-hydroxy or keto acids, amides, ammonium salts, other inorganic salts and esters of these. The compositions may also contain one or more of UVA filters, UVB filters, derivatives of vitamin E, Vitamin C or its derivatives. The compositions may contain conventional additives. A preferred plant extract is that of licorice (Glycyrrhiza Glabra) and of related plant species. Such compositions also prevent to a large extent formation of skin spots.

Hadas, Nira. “Skin whitening composition.” U.S. Patent No. 5,609,875. 11 Mar. 1997.

 

Dimethicone

A 3-in-1 Perineal Care Washcloth Impregnated With Dimethicone 3% Versus Water and pH Neutral Soap to Prevent and Treat Incontinence-Associated Dermatitis: A Randomized, Controlled Clinical Trial

CONCLUSION: The use of a 3-in-1 washcloth, impregnated with a 3% dimethicone formula, resulted in a significantly reduced prevalence of IAD and a trend toward less severe lesions. These findings provide indicative evidence for the use of 3-in-1 perineal care washcloth as an effective intervention against the use of water and a pH neutral soap to prevent and/or treat IAD.

Beeckman, Dimitri, et al. “A 3-in-1 perineal care washcloth impregnated with dimethicone 3% versus water and pH neutral soap to prevent and treat incontinence-associated dermatitis: a randomized, controlled clinical trial.” Journal of Wound Ostomy & Continence Nursing 38.6 (2011): 627-634.

 

A bioengineering study on the efficacy of a skin protectant lotion in preventing SLS‐induced dermatitis

Abstract

Background/aims: This study evaluated the efficacy of a dimethicone skin protectant lotion against sodium lauryl sulfate (SLS)‐induced irritant contact dermatitis (ICD) by clinical visual grading and bioengineering techniques in 12 healthy humans.

Methods: The flexor aspects of both forearms of the subjects were used as test sites. Each test was duplicated to diminish the variations of the test sites. In a random order and a double‐blind manner, two test sites were pretreated either with the testing protectant lotion or with its vehicle control prior to contact with SLS. Thirty minutes later, 0.2 ml of 0.5% SLS in a polypropylene chamber was applied to each pretreated site. One additional test site served as a positive control (without lotion), receiving the irritant only. After 24 h of exposure to the irritant, the chambers were removed. The efficacy of protective effect was determined by four parameters: visual scoring (VS), transepidermal water loss (TEWL), skin color (a* value), and cutaneous blood flow volume (BFV). All test sites were assessed with the parameters daily for 5 days.

Results: The VS data showed a significant decrease on the site pretreated with protectant lotion in comparison with the SLS‐only treated site (P<0.01) and with the site pretreated with control vehicle (P<0.05) (overall for 5 days). TEWL value was significantly decreased in comparison with the SLS‐only treated site (P=0.02 at day 2; P=0.008 at day 4; P=0.014 at day 5) and with the site pretreated with the control vehicle (P<0.05) (day 2, 4 and 5). However, the BFV and a* values did not show a statistical difference between protectant lotion, vehicle, and SLS‐only treated sites.

Conclusions: This study demonstrated that appropriate dimethicone skin protection products may provide certain benefits from surfactant ICD. The skin protectant lotion may be used to prevent ICD in home or work environments, where skin irritants may induce dermatitis or eczema.

Zhai, Hongbo, et al. “A bioengineering study on the efficacy of a skin protectant lotion in preventing SLS‐induced dermatitis.” Skin research and technology 6.2 (2000): 77-80.

 

A systematic review of contact dermatitis treatment and prevention

 

Background

Contact dermatitis (CD) is a common occupational disease. There have been no systematic reviews of CD treatment or prevention.

 

Methods

Multiple databases were systematically searched. Using independent double review and published quality review criteria, articles were rated as good, fair, or poor. Treatment benefit data were tabulated and conclusions were based on the rated strength of published evidence.

 

Results

In all, 49 studies met inclusion criteria. Barrier creams containing dimethicone or perfluoropolyethers, cotton liners, and softened fabrics prevent irritant CD. Lipid-rich moisturizers both prevent and treat irritant CD. Topical skin protectant and quaternium 18 bentonite (organoclay) prevent rhus dermatitis. Diethylenetriamine pentaacetic acid (chelator) cream prevents nickel, chrome, and copper dermatitis. Potent or moderately potent steroids effectively treat allergic CD. There were no macrolide immunomodulator trials that met inclusion criteria. This review did not include studies of children, animals, or non-English language publications.

 

Conclusions

A limited number of interventions effectively prevent or treat irritant and allergic CD, but well-controlled, outcome-blinded studies, particularly in the area of allergic CD prevention are needed.

 

Saary, Joan, et al. “A systematic review of contact dermatitis treatment and prevention.” Journal of the American Academy of Dermatology 53.5 (2005): 845-e1.

 

Dimethyl MEA

 

Investigation of a novel MEA for direct dimethyl ether fuel cell

Abstract

In this study, we presented the novel membrane electrode assembly (MEA) for direct dimethyl ether fuel cell (DDFC). The anode diffusion layer of the MEA consisted of hydrophilic region and hydrophobic region (with a ratio of region areas of 1:1). The electrochemical impedance spectra analyses revealed that the mass transfer resistance of novel MEA was lower than that of completed hydrophilic or hydrophobic MEA. The performance of novel MEA for DDFC was enhanced due to the promotion the mass transport of DME fuel at 50 °C. The constant current operation curves showed that the performance decay ratio of the novel MEA was lower than that of conventional MEAs. It indicated that the novel MEA benefited the long-term operation of DDFC.

Cai, Ke-Di, et al. “Investigation of a novel MEA for direct dimethyl ether fuel cell.” Electrochemistry Communications 10.2 (2008): 238-241.

 

Metal complexes of mercaptoamines—III. Different behaviour of β- and γ-(N,N-dimethyl)-mercaptoamines

Abstract

The complexes Ni6(MPDMA)12, [Ni6(MPDMAH)12]X12 X = (I, ClO4) and Pd2(MPDMA)2Cl2 (MPDMA = t-S(CH2)3N(CH3)2) have been prepared and characterized. An X-ray diffraction study shows that the structure of [Ni6(MPDMAH)12] (ClO4)12 consists of a cyclic hexanuclear array of nickel atoms linked by sulphur bridging ligands. Infrared and electronic spectra show that there is no chelation in any of the nickel complexes. However, coordination through the nitrogen atoms occurs in the palladium complex. This behaviour differs from that of the homologous β-mercaptoamine, which forms monomeric chelate complexes with both nickel and palladium.

Barrera, H., et al. “Metal complexes of mercaptoamines—III. Different behaviour of β-and γ-(N, N-dimethyl)-mercaptoamines.” Polyhedron 3.8 (1984): 969-975.

 

Synthesis, Isomerization, and Antimicrobial Evaluation of Some Pyrazolopyranotriazolopyrimidine Derivatives

Abstract

6‐Amino‐5‐imino‐pyrazolo[4′,3′:5,6]pyrano[2,3‐d]pyrimidine derivative 4 and pyrazolo‐[4′,3′:5,6]pyrano[2,3‐d]pyrimidin‐5‐ylhydrazine derivative 5 were prepared starting from 6‐amino‐3‐methyl‐4‐(p‐nitrophenyl)‐2,4‐dihydropyrano[2,3‐c]pyrazole‐5‐carbonitrile 1. The synthesis and structure characterization of 9,11‐dihydropyrazolo[4′,3′:5,6]pyrano[3,2‐e][1,2,4]triazolo[4,3‐c]pyrimidine derivatives 7 and 9 and their isomerization to 9,11‐dihydropyrazolo[4′,3′:5,6]pyrano[3,2‐e] [1,2,4]triazolo[1,5‐c]pyrimidine derivatives 6 and 8, respectively, under different suitable reaction conditions are reported. Moreover, the synthesis of 9,11‐dihydropyrazolo[4′,3′:5,6]pyrano[3,2‐e] tetrazolo[1,5‐c]pyrimidine derivative 14 and N9‐acyclic nucleoside 15 are described. Some of the prepared products showed potent antimicrobial activity.

Shamroukh, Ahmed H., et al. “Synthesis of Pyrazolo [4′, 3′: 5, 6] pyrano [2, 3‐d] pyrimidine Derivatives for Antiviral Evaluation.” Archiv der Pharmazie: An International Journal Pharmaceutical and Medicinal Chemistry 340.5 (2007): 236-243.

 

Lactic Acid

Effects of alpha-hydroxy acids on the human skin of Japanese subjects: The rationale for chemical peeling

ABSTRACT

Alpha-hydroxy acid (AHA) agents, such as glycolic acid and lactic acid, have been used as therapeutic agents for more than a quarter of a century. Recently, they have been used as agents to rejuvenate photo-aged skin. It is believed that these AHA agents induce the epidermis to remodel and accelerate desquamation, thus exerting their therapeutic effects. In this study, we investigated the histological differences in skin treated with glycolic, lactic, citric and acetic acids once daily for 6 weeks. The melanin pigments in the basal layer were less prominent in the glycolic and lactic acid-treated skin than in the citric and acetic acid-treated skin. The melanin deposits in the horny layers were equal for all AHA. However, the melanin deposits in the squamous layers were less prominent in the glycolic and lactic acid-treated skins than in the citric and acetic acid-treated skins; this was analogous to observations of the basal layers. Collagen I and procollagen I were increased after treatment with glycolic, lactic and citric acid in the upper dermis, but were not increased with acetic acid treatment. However, the staining of the epidermis and dermis for matrix metalloproteinase-1 (MMP-1) after treatment was not significantly different among the agents. Our data suggest that longer treatment intervals with glycolic and lactic acid can cause improvements in both the epidermal and dermal components and support the usefulness of AHA for rejuvenating photo-damaged skin.

Yamamoto, Yuki, et al. “Effects of alpha‐hydroxy acids on the human skin of Japanese subjects: The rationale for chemical peeling.” The Journal of dermatology 33.1 (2006): 16-22. DOI: 10.1111/j.1346-8138.2006.00003.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1346-8138.2006.00003.x/abstract?userIsAuthenticated=false&deniedAccessCustomisedMessage=

 

Treatment of skin keratoses with α-hydroxy acids and related compounds

ABSTRACT

Preventive as well as therapeutic treatment to alleviate the symptoms of skin keratoses consisting of topical application of a solution, gel, lotion, cream or ointment containing one or more of the α- or β-hydroxy acids or α-keto acids, esters thereof, and their amine salts is disclosed. The compounds include free acid or amine salt forms of α-hydroxy-butyric acid, α-hydroxyisobutyric acid, α-hydroxyisocaproic acid, α-hydroxyisovaleric, atrolactic acid, β-hydroxybutyric acid, β-phenyl lactic acid, β-phenylpyruvic acid, citric acid, ethyl pyruvate, galacturonic acid, glucoheptonic acid, glucoheptono 1,4-lactone, gluconic acid, gluconolactone, glucuronic acid, glucuronolactone, glycolic acid, isopropyl pyruvate, lactic acid, malic acid, mandelic acid, methyl pyruvate, mucic acid, pyruvic acid, saccharic acid, saccharic acid 1,4-lactone, tartaric acid, and tartronic acid. The therapeutic composition may include one or more of the compounds present in the total amount of from three to thirty percent. Topical application to affected areas has been found to achieve from substantial to complete remissions of the keratoses in humans.

Van Scott, Eugene J., and J. Yu Ruey. “Treatment of skin keratoses with α-hydroxy acids and related compounds.” U.S. Patent No. 4,234,599. 18 Nov. 1980.

https://www.google.com/patents/US4234599

 

The influence of different acids and pepsin on the extractability of collagen from the skin of Baltic cod (Gadus morhua)

Abstract

Solutions of (0.5 M) citric, lactic and acetic acids and 0.15 M HCl were used for the extraction of collagen from the whole skins of Baltic cod (Gadus morhua). The extractions were performed at a temperature of 4 °C for 24, 48 and 72 h using a solid/solution ratio of 1:6 (w/v). Of the acids used, HCl was the least effective solvent for collagen. The maximal yield of collagen extracted with citric acid was 60%. Collagen extraction with acetic or lactic acid give a maximal yield of about 90% with HCl yielding of only 18%. After enzymatic treatment of cod skin the yield of protein extracted with HCl and citric acids increased to 40% and 20%, respectively. Collagen was completely solubilized under the same conditions in acetic and lactic acids. Electrophoretic analysis of collagens extracted in HCl and citric acids with enzymatic treatment proved that the isolated protein was denaturated. The solutions of acetic and lactic acids are solvents for native collagen.

Skierka, Elżbieta, and Maria Sadowska. “The influence of different acids and pepsin on the extractability of collagen from the skin of Baltic cod (Gadus morhua).” Food chemistry 105.3 (2007): 1302-1306. doi:10.1016/j.foodchem.2007.04.030

http://www.sciencedirect.com/science/article/pii/S0308814607003858

 

Acrylates/Steareth-20 Methacrylate Copolymer

 

Antimicrobial skin preparation

Abstract

An antimicrobial skin composition comprised of an antimicrobial agent, an alcohol, one or more pH sensitive viscosity builders and water. Preferably, the viscosity builders of the present invention are comprised of pH sensitive methacrylic polymers which are alcohol compatible and have pH controlled water solubility. The composition combines the advantages of an antimicrobial agent and an alcohol, and has a viscosity of from 100 cp to 1,000. This viscosity is sufficiently low for purposes of dispensing and applying the preparation, yet sufficiently high to cause the solution to remain in the area of the wound and not flow away or pool under the patient. The preparation further forms a water-resistant film that is difficult to remove during wound irrigation, but can be easily removed upon completion of the procedure. Finally, the preparation is fast drying so as to take advantage of the fast high initial kill properties of alcohol.

Childers, David Alan. “Antimicrobial skin preparation.” U.S. Patent No. 8,206,696. 26 Jun. 2012.

 

Magnesium Ascorbyl Phosphate

Simultaneous Determination of Magnesium Ascorbyl Phosphate, Ascorbyl Glucoside, Kojic Acid, Arbutin and Hydroquinone in Skin Whitening Cosmetics by HPLC

A high performance liquid chromatographic method was developed for simultaneous determination of 5 whitening ingredients: magnesium ascorbyl phosphate, ascorbyl glucoside, kojic acid, arbutin and hydroquinone decomposed from arbutin in cosmetics.

Samples were extracted with 0.05 M KH2PO4 buffer solution (pH 2.5) and analyzed using a Cosmosil 5 C18-AR-II column. A mixture of 0.05 M KH2PO4 buffer solution (pH 2.5) and methanol (99:1, v/v) was used as mobile phase. The UV detector was set at 280 nm.

Pyridoxine was used as an internal standard. The related coefficients, R2 , of regression equations of the 5 standard curves were 0.9998-1.0000. The relative standard deviations of the 5 ingredients for intraday and interday analysis were less than 2.4%. The average

recoveries of these 5 ingredients spiked in sample ranged from 93.5% to 103.3%. The relative standard deviations of average recoveries were less than 1.3%. The limits of quantitation in cosmetics were 80.0, 20.0, 3.0, 15.0 and 10.0 µg/mL for magnesium ascorbyl phosphate, ascorbyl glucoside, kojic acid, arbutin and hydroquinone, respectively.

HUANG, SHOU-CHIEH, et al. “Simultaneous determination of magnesium ascorbyl phosphate, ascorbyl glucoside, kojic acid, arbutin and hydroquinone in skin whitening cosmetics by HPLC.” Journal of Food and Drug Analysis 12.1 (2004).

 

High-performance liquid chromatographic determination of ionic compounds in cosmetic emulsions: application to magnesium ascorbyl phosphate

Abstract

A rapid, reliable method based on reversed-phase high performance liquid chromatography for the qualitative and quantitative determination of magnesium ascorbyl phosphate (VC-PMG) in both standard solutions and cosmetic products is reported. The procedure, based on an aminic stationary phase and acetonitrile-0.3 M phosphate buffer (pH 4) (40:60) as the mobile phase, allows the determination of VC-PMG in cosmetic samples after dilution with a tetrahydrofuran-0.3 M phosphate buffer (pH 4) (3:7) solvent mixture.

Semenzato, A., et al. “High-performance liquid chromatographic determination of ionic compounds in cosmetic emulsions: application to magnesium ascorbyl phosphate.” Journal of Chromatography A 705.2 (1995): 385-389.

Histopathological, morphometric and stereological studies of ascorbic acid and magnesium ascorbyl phosphate in a skin care formulation

Synopsis

Ascorbic acid (vitamin C) has been widely used in cosmetics and dermatological formulations due to its inhibitory effect on melanogenesis by affecting collagen synthesis and scavenger properties. However, ascorbic acid (AA) is quickly oxidized and decomposes in aqueous solution and to solve this problem, vitamin C derivatives were synthesized.

In the present investigation, histopathological, morphometric and stereological studies were carried out to investigate the possible alterations caused by formulations containing AA or magnesium ascorbyl phosphate (MAP) in the epidermis.

Gel creams either with or without 2% AA or its derivative were selected for investigation. Guinea‐pigs were shaved on the back, and four areas of 1.5 cm2 each were used for the experiments. One untreated area was used for control and the others for the application of gel cream formulations either with or without AA or its derivatives. The formulations were applied daily for 2, 4 and 8 weeks and biopsies were then obtained from each area using a dermatological punch. The material collected was analysed by histopathological, morphometric and stereological techniques.

We observed that, under the present experimental conditions, whole formulations acted on the epidermis causing a thickening of the epithelium, with cells of larger volume in the granulose and spinous layers.

Campos, Maia. “Histopathological, morphometric and stereological studies of ascorbic acid and magnesium ascorbyl phosphate in a skin care formulation.” International journal of cosmetic science 22.3 (2000): 169-179.

 

Aloe Vera Gel

The Effect of Aloe Vera Gel/Mild Soap Versus Mild Soap Alone in Preventing Skin Reactions in Patients Undergoing Radiation Therapy.

Abstract:

Purpose/Objectives: To determine whether the use of mild soap and aloe vera gel versus mild soap alone would decrease the incidence of skin reactions in patients undergoing radiation therapy. Data Sources: Prospective, randomized, blinded clinical trial. Setting: Radiation therapy outpatient clinic in a cancer center affiliated with a major teaching medical facility. Sample: The mean age of the participants was 56 years. The group consisted of Caucasians (74%) and African Americans (26%). The ethnic mix was non-Hispanic (65%) and Hispanic (35%). Methods: Prophylactic skin care began on the first day of radiation therapy. Patients cleansed the area with mild, unscented soap. Patients randomized into the experimental arm of the trial were instructed to liberally apply aloe vera gel to the area at various intervals throughout the day. Findings: At low cumulative dose levels =2,700 cGy, no difference existed in the effect of adding aloe. When the cumulative dose was high (&gt; 2,700 cGy), the median time was five weeks prior to any skin changes in the aloe/soap arm versus three weeks in the soap only arm. When the cumulative dose increases over time, there seems to be a protective effect of adding aloe to the soap regimen. Implications for Nursing Practice: Skin products used to treat radiation dermatitis vary among institutions. Nurses should be aware that some patients may be predisposed to skin problems. Nurses must be aware of newly developed products and research regarding these products so that effective treatment can be instituted.

Olsen, Deborah Lee, et al. “The effect of aloe vera gel/mild soap versus mild soap alone in preventing skin reactions in patients undergoing radiation therapy.” Oncology nursing forum. Vol. 28. No. 3. 2001.

http://web.a.ebscohost.com/abstract?direct=true&profile=ehost&scope=site&authtype=crawler&jrnl=0190535X&AN=9521886&h=3E4mHqTZ6TK7B2cnMF5a8wETcX5wftJ5hygatu42DkB2ThvJUJtVzm9IpB6%2fR8M6Rr07NDpRLopleS6PeKEN1A%3d%3d&crl=c&resultNs=AdminWebAuth&resultLocal=ErrCrlNotAuth&crlhashurl=login.aspx%3fdirect%3dtrue%26profile%3dehost%26scope%3dsite%26authtype%3dcrawler%26jrnl%3d0190535X%26AN%3d9521886

 

Evaluation of aloe vera gel gloves in the treatment of dry skin associated with occupational exposure

Abstract

Objective: An examination glove that delivers aloe vera (AV) gel to the gloved hand was studied in 30 adult females with bilateral occupational dry skin with or without irritant contact dermatitis (with or without erythema, fissures, and excoriations). Methods: All participants were factory assembly-line workers with repeated superficial skin trauma who attributed their dry, irritated, emollient-dependent skin to a common cause (occupational exposure). Participants were sequentially enrolled (after written informed consent, n = 29 evaluable participants) into an open, contralateral comparison study to evaluate efficacy of AV glove use 8 h/day to one hand versus no use to the opposite hand for 30 days, followed by 30 days rest, followed by 10 days of repeated use. Participant’s dorsal hands were documented by standardized photos at baseline, during, and at the end of study. Results: Unblinded investigator baseline assessment rated dry skin as mild to moderate (n = 27), or moderate to severe (n = 2). Mean time to noticeable improvement for the AV glove hand was 3.5 days (range: 2-6 days) whereas marked improvement was 10.4 days (range: 7-17 days) for the AV glove hand. No improvement was detected for nonglove hands. Blinded photo assessment was rated independently by dermatology research staff. End-of-study mean global assessment of AV glove hands versus nonglove hands was 1.3 for AV glove hand (0 = no change, 1 = good [10%-89% global improvement], 2 = marked improvement [90%-100% global improvement]) versus 0 for nonglove hand (P <.0001). Mean global end-of-study assessments by the participants = 2.0 for AV glove hand versus 0 for nonglove hand. Conclusion: Dry-coated AV gloves that provide for gradual delivery of AV gel to skin produced a uniformly positive outcome of improved skin integrity, decreased appearance of fine wrinkling, and decreased erythema in the management of occupational dry skin and irritant contact dermatitis. (Am J Infect Control 2003;31:40-2.)

West, Dennis P., and Ya Fen Zhu. “Evaluation of aloe vera gel gloves in the treatment of dry skin associated with occupational exposure.” American Journal of Infection Control 31.1 (2003): 40-42. doi:10.1067/mic.2003.12

http://www.sciencedirect.com/science/article/pii/S0196655302482120

 

The Stimulation of Postdermabrasion Wound Healing with Stabilized Aloe Vera Gel-Polyethylene Oxide Dressing

Abstract

Full-face dermabrasion provided an ideal opportunity to document the effects of dressings on wound healing management. Following the procedure, the abraded face was divided in half. One side was treated with the standard polyethylene oxide gel wound dressings. The other side was treated with a polyethylene oxide gel dressing saturated with stabilized aloe vera. The polyethylene oxide dressing provided an excellent matrix for the release of aloe vera gel during the initial 5 days of wound healing. By 24–48 hours there was dramatic vasoconstriction and accompanying reduction in edema on the aloe-treated side. By the third to fourth day there was less exudate and crusting at the aloe site, and by the fifth to sixth day the reepithelialization at the aloe site was complete. Overall, wound healing was approximately 72 hours faster at the aloe site. This acceleration in wound healing is important to reduce bacterial contamination, subsequent keloid formation, and/or pigmentary changes. The exact mechanism of acceleration of wound healing by aloe vera is unknown.

FULTON, JAMES E. “The Stimulation of Postdermabrasion Wound Healing with Stabilized Aloe Vera Gel‐Polyethylene Oxide Dressing.” The Journal of dermatologic surgery and oncology 16.5 (1990): 460-467. DOI: 10.1111/j.1524-4725.1990.tb00065.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1524-4725.1990.tb00065.x/abstract?userIsAuthenticated=false&deniedAccessCustomisedMessage=

 

Aloe vera leaf gel: a review update

Abstract

Research since the 1986 review has largely upheld the therapeutic claims made in the earlier papers and indeed extended them into other areas. Treatment of inflammation is still the key effect for most types of healing but it is now realized that this is a complex process and that many of its constituent processes may be addressed in different ways by different gel components. A common theme running though much recent research is the immunomodulatory properties of the gel polysaccharides, especially the acetylated mannans from Aloe vera, which are now a proprietary substance covered by many patents. There have also been, however, persistent reports of active glycoprotein fractions from both Aloe vera and Aloe arborescens. There are also cautionary investigations warning of possible allergic effects on some patients. Reports also describe antidiabetic, anticancer and antibiotic activities, so we may expect to see a widening use of aloe gel. Several reputable suppliers produce a stabilized aloe gel for use as itself or in formulations and there may be moves towards isolating and eventually providing verified active ingredients in dosable quantities

Reynolds, T., and A. C. Dweck. “Aloe vera leaf gel: a review update.” Journal of ethnopharmacology 68.1 (1999): 3-37. doi:10.1016/S0378-8741(99)00085-9

http://www.sciencedirect.com/science/article/pii/S0378874199000859

 

A Phase III Study on the Efficacy of Topical Aloe Vera Gel on Irradiated Breast Tissue

Abstract

The aim of the study was to see if topical aloe vera gel would be beneficial in reducing the identified skin side-effects of radiation therapy, including erythema, pain, itching, dry desquamation, and moist desquamation, when compared with aqueous cream. The secondary aim was to assess the effect of other factors known to predict severity of radiation skin reaction, ie, breast size, smoking habit, and one or more drainages of lymphocele after surgery, on other skin side effects.

A Phase III study was conducted involving 225 patients with breast cancer after lumpectomy or partial mastectomy, who required a course of radiation therapy using tangential fields. Patients were randomized to either topical aloe vera gel or topical aqueous cream to be applied 3 times per day throughout and for 2 weeks after completion of radiation treatment. Weekly skin assessments were performed by nursing staff.

Aqueous cream was significantly better than aloe vera gel in reducing dry desquamation and pain related to treatment. Subjects with D cup or larger size breasts experienced significantly more erythema, regardless of treatment arm. For subjects who had undergone lymphocele drainage, the aloe vera group experienced significantly more pain than the aqueous cream group. Within the aqueous cream arm, smokers were significantly more likely to experience itching within the treatment field than were nonsmokers. Within the aloe vera arm, subjects who had undergone one or more lymphocele drainages after surgery were significantly more likely to experience erythema and itching within the treatment field than those who did not have drainage.

In this study, aloe vera gel did not significantly reduce radiation-induced skin side effects. Aqueous cream was useful in reducing dry desquamation and pain related to radiation therapy.

Heggie, Sue, et al. “A phase III study on the efficacy of topical aloe vera gel on irradiated breast tissue.” Cancer nursing 25.6 (2002): 442-451.

http://journals.lww.com/cancernursingonline/Abstract/2002/12000/A_Phase_III_Study_on_the_Efficacy_of_Topical_Aloe.7.aspx

 

Aloe Vera for Preventing Radiation-induced Skin Reactions: A Systematic Literature Review

Abstract

Aim

To systematically review and critically appraise the evidence for effectiveness of Aloe vera gel for radiation-induced skin reactions.

Materials and methods

Major biomedical databases and specialist complementary and alternative medicine databases were searched. Additionally, efforts were made to identify unpublished and ongoing research. Relevant research was systematically categorised by study type and appraised according to study design. Clinical commentaries were obtained for each study included in the review.

Results

One earlier systematic review on Aloe vera for a variety of conditions was located. Five published randomised-controlled trials (RCTs) were found, along with two additional RCTs that are not published. No non-RCTs, uncontrolled studies or qualitative studies were found.

Conclusions

There is no evidence from clinical trials to suggest that topical Aloe vera is effective in preventing or minimising radiation-induced skin reactions in cancer patients. Further methodologically rigorous, sufficiently powered research studies should be conducted to evaluate the effectiveness of currently used and novel therapies for the prevention, minimisation and management of radiation-induced skin reactions.

Richardson, Janet, et al. “Aloe vera for preventing radiation-induced skin reactions: a systematic literature review.” Clinical Oncology 17.6 (2005): 478-484. doi:10.1016/j.clon.2005.04.013

http://www.sciencedirect.com/science/article/pii/S0936655505002050

 

Quality and authenticity of commercial aloe vera gel powders

Abstract

This study provides a survey of commercial aloe vera gel powders. Nine products, obtained from leading international suppliers, were examined and compared with fresh aloe vera gel. A multi-technique approach was chosen to assess their quality and authenticity. Authenticity was evaluated by nuclear magnetic resonance spectrometry (1H NMR). The absence of adulterants, impurities, and preservatives was also investigated by this technique. The amount of mannose after acid hydrolysis gave a direct and rapid measurement of the concentration of the polysaccharide acemannan in the gel powder. The quality of the samples analysed was found to be very inconsistent and in some cases extremely poor. Only three products, out of the nine analysed, contained satisfactory amounts of acemannan (ca. 10%, w/w) whereas the remaining samples exhibited very low levels. Two samples only contained ca. 1% (w/w). Four samples showed a high degree of enzymatic degradation and bacterial fermentation. One contained an abnormally high concentration of free glucose (ca. 30%, w/w). An HPLC–UV method was set up to verify the absence of hydroxyanthracene derivatives (aloin and aloin-related compounds). Aloin A was found to be present at concentrations from trace levels to ca. 16 mg/kg.

Bozzi, A., et al. “Quality and authenticity of commercial aloe vera gel powders.” Food chemistry 103.1 (2007): 22-30. doi:10.1016/j.foodchem.2006.05.061

http://www.sciencedirect.com/science/article/pii/S0308814606006066

 

Investigation of the Anti-Inflammatory Potential of Aloe vera Gel (97.5%) in the Ultraviolet Erythema Test

Abstract

Background:Aloe vera is a natural product that is frequently used in soothing skin care products such as aftersun lotions. In the present study we aimed to explore the anti-inflammatory potential of a highly concentrated A. vera gel in the UV erythema test in vivo. Methods: 40 volunteers with skin types II and III were included in the randomized, double-blind, placebo-controlled, phase III monocenter study. Test areas on the back were irradiated with the 1.5-fold minimal erythema dose of UVB. Subsequently, the test areas were treated occlusively on 2 subsequent days with A. vera gel (97.5%), the positive controls (0.25% prednicarbate, 1% hydrocortisone in placebo gel and 1% hydrocortisone cream) and a placebo gel. Erythema values were determined photometrically after 24 and 48 h. Results:A. vera gel (97.5%) significantly reduced UV-induced erythema after 48 h, being superior to 1% hydrocortisone in placebo gel. In contrast, 1% hydrocortisone in cream was more efficient than A. vera gel. Conclusions: In this study after 48 h the A. vera gel (97.5%) displayed some anti-inflammatory effects superior to those of 1% hydrocortisone in placebo gel. The A. vera gel tested here might be useful in the topical treatment of inflammatory skin conditions such as UV-induced erythema.

Reuter, J., et al. “Investigation of the anti-inflammatory potential of Aloe vera gel (97.5%) in the ultraviolet erythema test.” Skin pharmacology and physiology 21.2 (2008): 106-110.

http://www.karger.com/Article/Abstract/114871

 

Moisturizing effect of cosmetic formulations containing Aloe vera extract in different concentrations assessed by skin bioengineering techniques

Abstract

Background/purpose: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques.

Methods: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (CorneometerTM CM 825 and TewameterTM TM 210) were analysed before and after a single and 1- and 2-week period of daily application.

Results: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle.

Conclusion: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin.

Dal’Belo, Susi Elaine, et al. “Moisturizing effect of cosmetic formulations containing Aloe vera extract in different concentrations assessed by skin bioengineering techniques.” Skin Research and Technology 12.4 (2006): 241-246. DOI: 10.1111/j.0909-752X.2006.00155.x

http://onlinelibrary.wiley.com/doi/10.1111/j.0909-752X.2006.00155.x/abstract?userIsAuthenticated=false&deniedAccessCustomisedMessage=

 

Polysorbate 20

Determination of CMC of polysorbate 20 in aqueous solution by surface tension method

Abstract

The CMC of polysorbate 20 was determined using a surface tension method; the concentration (C) of polysorbate 20 studied varied from 0.001 to 10.000 mg./ml. The results show clearly that the surface tension (γ) decreases linearly with log C up to a concentration of 0.06 mg./ml. and is practically constant for more concentrated solutions. This suggests that the CMC of polysorbate 20 is in the vicinity of 0.06 mg./ml., which is in excellent agreement with the values obtained by other methods.

Mittal, K. L. “Determination of CMC of polysorbate 20 in aqueous solution by surface tension method.” Journal of pharmaceutical sciences 61.8 (1972): 1334-1335.

 

Penetration Enhancing Effect of Polysorbate 20 and 80 on the In Vitro Percutaneous Absorption of LAscorbic Acid

Abstract

Purpose: To investigate the penetration enhancing effect of two polysorbates – polyoxyethylene 20 (POE-20) and polyoxyethylene 80 (POE-80) – on the in vitro percutaneous absorption of ascorbic acid (AA).

Methods: For the permeation experiments, Franz diffusion cell covered with aluminum foil providing an effective diffusion area of 1.76 cm2 and hairless rabbit skin were used. A range of concentrations (1 – 5 %) of POE-20 and POE-80 was added to the ascorbic acid to determine their optimum enhancement concentration.

Results: The cumulative amount of AA that diffused across the skin increased with increase in the concentration of the permeation enhancers. Without the enhancer, AA flux was 0.626 μg/cm2/h while mean permeability coefficient (Kp) was 2.09 × 10-6 cm/h. AA flux was 3.17 and 2.44 μg/cm2/h for POE-20 and POE-80, respectively, while mean permeability coefficient was 10.6 × 10-6 and 8.14 × 10-6 Kp, cm/h. Maximum flux (3.16 μg/cm2/h) at POE-20 concentration of 5 % was obtained, with an enhancement ratio (ER) of 5.07 in relation to control (i.e., AA without enhancer). For POE-80 (5 %), maximum flux was 2.44 μg/cm2/h with an ER value of 3.89, compared to control.

Conclusion: This study demonstrates that POE-20 and POE-80 exerted a penetration enhancing effect on the percutaneous absorption of L-ascorbic acid (AA).

Akhtar, Naveed, et al. “Penetration enhancing effect of polysorbate 20 and 80 on the in vitro percutaneous absorption of lascorbic acid.” Tropical Journal of Pharmaceutical Research 10.3 (2011).

 

 

Silk Aminoacids

Silk sericin as a moisturizer: an in vivo study

Summary
Background Excessive transepidermal water loss (TEWL) is the one of the causes of dry skin, and skin moisturizers have been used to overcome it.

Aim The purpose of this research was to study the moisturizing effect of sericin, a silk protein. Because silk sericin has resemblance with the natural moisturizing factor (NMF), it has been studied for its application in skin cosmetics.

Methods Sericin gels were prepared using sericin solution and with pluronic and carbopol as stabilizers. The gels were applied on the skin of healthy human volunteers and its moisturizing efficiency was evaluated by measuring the skin hydroxyproline content, impedance, TEWL, and scanning electron microscopy (SEM) results.

Results Decrease in skin impedance, increase in hydroxyproline level, and hydration of epidermal cells revealed the moisturizing effect of sericin, whereas decrease in the value of TEWL may be attributed to occlusive effect, which prevents water loss from the upper layer of the skin. Skin surface topography revealed the smoothness of the upper layer of the skin as a result of moisturization.

Conclusion Increase in the intrinsic moisturization of skin by sericin may be attributed to restoration of the amino acids and its occlusive effect. Thus, it would become a promising and important moisturizing ingredient in moisturizing formulations.

Padamwar, Mahesh N., et al. “Silk sericin as a moisturizer: an in vivo study.” Journal of Cosmetic Dermatology 4.4 (2005): 250-257.

 

Covalent bonding of active agents to skin, hair or nails

Abstract

Transglutaminase crosslinks proteins by catalyzing the formation of isopeptide bonds between lysine and glutamine residues. Transglutaminase may be used to crosslink beneficial actives containing an amine moiety to glutamine residues in skin, hair or nails. A variety of beneficial actives, e.g., sunscreens, antimicrobial compounds, skin conditioning agents, hair conditioning agents, anti-inflammatory compounds, antioxidants, coloring agents, perfumes, insect repellants, can thus be delivered to human skin, hair, or nails.

Richardson, Norman K., et al. “Covalent bonding of active agents to skin, hair or nails.” U.S. Patent No. 5,490,980. 13 Feb. 1996.

 

Imidazolidinyl Urea

Gel compositions

ABSTRACT

There is provided a clear antiperspirant/deodorant gel composition. The composition is a water-in-oil emulsion having a viscosity about 7,000 cps to about 25,000 cps and a clarity from about 30 NTU or less. The composition further has an antiperspirant active, water, silicone gelling agent, and one or more silicone oils.

Carmody, Walter J. “Clear antiperspirant or deodorant; water in oil emulsion including silicone gelling agent and silicone oils; soft, nonirratating feel to skin; using such as diazolidinyl or imidazolidinyl urea as formaldehyde donor.” U.S. Patent No. 6,468,512. 22 Oct. 2002.

https://www.google.com/patents/US6468512

 

Methylchloroisothiazolinone/Methylisothiazolinone (Kathon CG) Biocide: Second United States Multicenter Study of Human Skin Sensitization.

Abstract

Background: This is the second United States multicenter study of human skin sensitization to methylchloroisothiazolinone/methylisothiazolinone (MCI/MI). From January 1991 through March 1992 patients treated in 11 patch test clinics were patch tested to 100 ppm MCI/MI, formaldehyde 1% aqueous, quaternium-15 2% petrolatum, imidazolidinyl urea 2% petrolatum, and paraben mix 12% petrolatum.

Results: Twenty-three of the 1,259 patch test patients (1.8%) had positive patch test reactions to MCI/MI. Thirteen of the 23 (56.5%) were thought to be relevant to the presenting dermatitis. The frequency of positive patch test reactions to the other allergens was quaternium-15, 7.2%; formaldehyde, 7.1%; imidazolidinyl urea, 2.2%; and paraben mix, 1.4%.

Conclusion: Skin sensitization to MCI/MI has not changed significantly since the first United States multicenter study in 1988 to 1989. The rate of positive patch test responses to MCI/MI was comparable with that for parabens and imidazolidinyl urea and significantly less than for formaldehyde and quaternium-15.

Marks Jr, James G., et al. “Methylchloroisothiazolinone/Methylisothiazolinone (Kathon CG) Biocide: Second United States Multicenter Study of Human Skin Sensitization.” Dermatitis 4.2 (1993): 87-89.

http://journals.lww.com/dermatitis/Abstract/1993/06000/Methylchloroisothiazolinone_Methylisothiazolinone.4.aspx

 

Dermatological composition

ABSTRACT

Dermatological compositions described herein using from about 21 to about 40 wt-% urea with skin protectants of an oleaginous nature for treating a variety of dermatological conditions manifested by dry skin. The composition does not require use of traditional preservatives.

Valdez, Vitalia, and Albert Fleischner. “21 to about 40 wt-% urea with skin protectants of an oleaginous nature for treating a variety of dermatological conditions manifested by dry skin. the composition does not require use of traditional preservatives.” U.S. Patent No. 5,919,470. 6 Jul. 1999.

https://www.google.com/patents/US5919470

 

Contact sensitivity to preservatives in the UK, 2004–2005: results of multicentre study

Abstract

Preservative sensitivity in the UK was last assessed in 2000. Given the changes in preservative usage, we have re-evaluated our patch test data in order to detect any changes in the trend of sensitization. The results of patch testing using the extended British Contact Dermatitis Society Standard series were collected from 9 dermatology centres in the UK. Positive reactions to each of 10 preservative allergens were captured together with the MOAHFLA indices for each centre. In total, 6958 patients were tested during the period 2004–2005. The current data were compared with previously published data. Formaldehyde and methylchloroisothiazolinone/methyl-isothiazolinone have the highest positivity rates at 2.0% and chloroxylenol the lowest at 0.2%. Parabens mix has the highest irritancy rate. Compared with the UK data in 2000, the positivity rate of imidazolidinyl urea (0.02 < P < 0.05) has significantly increased and that of methyldibromo glutaronitrile has significantly reduced (P < 0.001).

Jong, Cherng T., et al. “Contact sensitivity to preservatives in the UK, 2004–2005: results of multicentre study.” Contact Dermatitis 57.3 (2007): 165-168. DOI: 10.1111/j.1600-0536.2007.01181.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0536.2007.01181.x/abstract?userIsAuthenticated=false&deniedAccessCustomisedMessage=

 

Skin cell renewal regime

ABSTRACT

A novel cell renewal cosmetic regime is disclosed, which increases epidermal cell turnover without skin irritation. The regime consists of the use of four components: a cleanser, a cream, a lotion, and a tonic.

Cella, John A., et al. “Skin cell renewal regime.” U.S. Patent No. 4,272,544. 9 Jun. 1981.

https://www.google.com/patents/US4272544

 

Patch testing with preservatives at St John’s from 1982 to 1993

Abstract

We have reviewed our patch test results for preservative allergy from 1982 to W3. 8 preservatives were included: formaldehyde. 2-bromo-2-nitropropane-1,3-diol (Bronopol™), quatenium-15 (Dowicil 200™). Imidazolidinyl urea (Germall 115™). diazolidinyl urea (Germall 11™) and 1,2-dibromo-2,4-dicyanpbutane (one of the constituents of Euxyl K 400™). Whereas the allergy rate to formaldehyde is quite stable, there is a slight increase in the imidazolidinyl urea allergy rate to formaldehyde is quite stable, there is a slight increase in the imidazolidinyl urea allergy rate. Quaternium-15’s rate a rapid rise seems to have stabilized. Although very important constituents of cosmetics, preservatives not only induce allergies on the face but also on the hands, and, as expected, the allergy rate in men and women generally differs. Among the 5 formaldehyde-releasers, there are some favoured simultaneous reactions quaternium -15 and formaldehyde, and diazolidinyl urea or imidazolidinyl urea. Coccomitant reactions between 1-brome-2-nitropropane-1,3-diol and formaldehyde are not common, and those between 2-brome-2-nitropropane-1,3-diol and disazolidynl urea or imidazolidinyl urea very uncommon. Concomitant reactions between imidazolidinyl urea, diazolidinyl urea, and formaldehyde are not very common. This supports the hypothesis that allergic reactions to the Germalls are directed toward the initial molecule rather than to formaldehyde.

Jacobs, M‐C., et al. “Patch testing with preservatives at St John’s from 1982 to 1993.” Contact dermatitis 33.4 (1995): 247-254. DOI: 10.1111/j.1600-0536.1995.tb00476.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0536.1995.tb00476.x/abstract

 

Formaldehyde-releasers in cosmetics in the USA and in Europe

Abstract

Background: Frequencies of sensitization to formaldehyde among US patients patch tested for suspected contact dermatitis are higher than in Europe. Cosmetics are an important source of contact with formaldehyde.

Objectives: To acquire data on the frequency of use of formaldehyde-releasers in cosmetics sold in the USA and Europe and their use concentrations. To assess whether any observed differences may contribute to the discrepancies in sensitization rates.

Methods: Enquiries with Food and Drug Administration (FDA), the European Cosmetics Association, and the Dutch Cosmetics Association. Reading the labels of skin care cosmetics in a local drugstore.

Results: The FDA provided data on the presence of formaldehyde and releasers. Nearly one fifth of all cosmetics contain a releaser. In 25% of 496 examined skin care products, releasers were present. In comparable FDA data categories, the percentage was 24. No data were found on use concentrations of the releasers in cosmetics in either the USA or Europe.

Conclusions: The percentages of stay-on skin care products containing a formaldehyde-releaser are virtually identical in the USA (FDA data) and our local drugstore sample. However, this does not necessarily imply that cosmetics play no part in the differences in formaldehyde sensitization rates.

De Groot, Anton C., and Margo Veenstra. “Formaldehyde‐releasers in cosmetics in the USA and in Europe.” Contact Dermatitis 62.4 (2010): 221-224. DOI: 10.1111/j.1600-0536.2009.01623.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0536.2009.01623.x/abstract?userIsAuthenticated=false&deniedAccessCustomisedMessage=

 

A method for quantification of formaldehyde in the presence of formaldehyde donors in skin-care products

Abstract

Reliable and uncomplicated methods for detection of free formaldehyde in products preserved with formaldehyde donors are desirable to decrease the risk of allergic contact dermatitis. The aim of this study was to develop a method that could be used in clinics and workplaces for quantification of free formaldehyde in products preserved with formaldehyde donors. The method developed is named the closed container diffusion (CCD) method. Formaldehyde in a sample is allowed to evaporate in a closed container and react with 2,4-dinitrophenylhydrazine coated on a glass fibre filter. The hydrazone formed is analyzed with HPLC. The method was tested on 3 different formaldehyde donors, imidazolidinyl urea, diazolidinyl urea and 2-bromo-2-nitropropane-1,3-diol, using 4 different cream bases. The results obtained with this method accord with those obtained with the official method within the European Union (EU). The method is sensitive enough for analysis of patients’ products and for control of labelled amounts of formaldehyde in technical products without solvent extraction. As a result of our studies, we observed a risk of exceeding the labelling limit for free formaldehyde in cosmetic products when using the highest amount of diazolidinyl urea allowed within the EU.

Karlberg, Ann‐Therese, et al. “A method for quantification of formaldehyde in the presence of formaldehyde donors in skin‐care products.” Contact dermatitis 38.1 (1998): 20-28. DOI: 10.1111/j.1600-0536.1998.tb05632.x

http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0536.1998.tb05632.x/abstract

 

Analytical control of preservative labelling on skin creams

Abstract

Contents of 23 preservatives (22 permitted and 1 non-permitted) were analysed in 67 skin creams to verify whether these products complied with the Cosmetic Directive with respect to ingredient labelling, as well as with respect to maximum allowed concentrations of the respective preservatives. The preservatives selected for the analysis were: parabens, 2-phenoxyethanol, benzoic acid, 4-hydroxybenzoic acid, sorbic acid, salicylic acid, formaldehyde and formaldehyde releasers, 3:1 mixture of 5-chloro-2-methyl-4-isothiazolin-2-one and 2-methyl-4-isothiazolin-2-one (Kathon CG), 2-bromo-2-nitropropane-1,3-diol (Bronopol), 5-bromo-2-nitro-1,3-dioxane (Bronidox) and methyldibromo glutaronitrile. 1 or more parabens were present in 87% (n=58) of the investigated products, 2-phenoxy ethanol in 49% (n=33) of the products, and formaldehyde/formaldehyde releasers were present in 51% (n=34) of the products. Kathon CG was found in 3 products, acid preservatives (except salicylic acid) in 8 products, Bronopol in 5 products, and methyldibromo glutaronitrile was present in 4 products. The contents of all of the target preservatives in the skin creams were within the maximum allowed concentrations of the respective substances. Incorrect ingredient labelling with respect to paraben content was found in 10% (n=7) of the investigated products, 33% (n=22) of the products were not declared for the content of formaldehyde/formaldehyde releaser, and 7% (n=5) products were incorrectly labelled for the content of 2-phenoxyethanol. In 1 of the products containing Kathon CG, the ratio of 5-chloro-2-methyl-4-isothiazolin-2-one to 2-methyl-4-isothiazolin-2-one (1.4:1) was not correct. 4 of the 8 products containing acid preservatives were not labelled for the content of these substances. All in all, in 45% (n=30) of the investigated skin creams ingredient labelling was incorrect with respect to preservative contents. The proportion of incorrect labelling is reduced to 23% (n=15), when the formaldehyde content in skin creams below 30 ppm is not accounted.

Rastogi, Suresh Chandra. “Analytical control of preservative labelling on skin creams.” Contact Dermatitis 43.6 (2000): 339-343. DOI: 10.1034/j.1600-0536.2000.043006339.x

http://onlinelibrary.wiley.com/doi/10.1034/j.1600-0536.2000.043006339.x/abstract

 

Antiinflammatory skin moisturizing composition and method of preparing same

ABSTRACT

A long lasting, esthetically pleasing medicated skin care moisturizing composition comprising

(1) an oil phase comprising oil from about 30% to about 80% and a non-ionic surface active agent having an HLB number of about 7 to about 12, wherein the non-ionic surface active agent is present in an amount of about 5% to about 9%;

(2) an aqueous phase comprising an aqueous thickening agent from about 0.05% to about 5% and water from about 15% to about 65%;

(3) an effective amount of a topical medicament; wherein the medicament is a corticosteroid and the oil phase is added to the aqueous phase to form an emulsion and a topical medicament admixed into the emulsion has been developed.

The method of preparation of the composition and a method of treating skin with the composition are also disclosed.

Geria, Navin M. “Antiinflammatory skin moisturizing composition and method of preparing same.” U.S. Patent No. 4,992,478. 12 Feb. 1991.

https://www.google.com/patents/US4992478

 

Sensitive-skin care regime

ABSTRACT

A method of decreasing the sensitivity of the skin without causing irritation is described, using a four component cosmetic regime. The four components comprising the regime are: a cleanser, a toner, a moisturizer, and a cream.

Flom, Merlyn G., et al. “Sensitive-skin care regime.” U.S. Patent No. 4,368,187. 11 Jan. 1983.

https://www.google.com/patents/US4368187

 

EDTA

The Vast Majority of CLA T Cells Are Resident in Normal Skin

There are T cells within normal, noninflamed skin that most likely conduct immunosurveillance and are implicated in the development of psoriasis. We isolated T cells from normal human skin using both established and novel methods. Skin resident T cells expressed high levels of CLA, CCR4, and CCR6, and a subset expressed CCR8 and CXCR6. Skin T cells had a remarkably diverse TCR repertoire and were mostly Th1 memory effector cells with smaller subsets of central memory, Th2, and functional T regulatory cells. We isolated a surprising number of nonexpanded T cells from normal skin. To validate this finding, we counted T cells in sections of normal skin and determined that there are ∼1 × 106 T cells/cm2 normal skin and an estimated 2 × 1010 T cells in the entire skin surface, nearly twice the number of T cells in the circulation. Moreover, we estimate that 98% of CLA+ effector memory T cells are resident in normal skin under resting conditions. These findings demonstrate that there is a large pool of memory T cells in normal skin that can initiate and perpetuate immune reactions in the absence of T cell recruitment from the blood.

The Vast Majority of CLA T Cells Are Resident in Normal Skin. Rachael A. Clark, Benjamin Chong, Nina Mirchandani, Nooshin K. Brinster, Kei-ichi Yamanaka, Rebecca K. Dowgiert and Thomas S. Kupper. The Journal of Immunology. April 1, 2006 vol. 176 no. 7 4431-4439. doi: 10.4049/​jimmunol.176.7.4431

Identification of the cutaneous basement membrane zone antigen and isolation of antibody in linear immunoglobulin A bullous dermatosis.

Linear IgA bullous dermatosis (LABD) is a rare blistering skin disease characterized by basement membrane zone deposition of IgA. This study identifies a tissue antigen detected by patient serum and then isolates the autoantibody using epidermis and protein bands blotted on nitrocellulose as immunoabsorbents. Sera from 10 patients (9 with cutaneous disease and 1 with cicatrizing conjunctivitis) were evaluated. Indirect immunofluorescence revealed an IgA anti-basement membrane antibody in 6 of 10 sera with monkey esophagus substrate and 9 of 10 sera with human epidermal substrate. Immunoblotting was performed on epidermal and dermal extracts prepared from skin separated at the basement membrane zone with either sodium chloride or EDTA. Saline-separated skin expressed a 97-kD band in dermal extract alone that was recognized by 4 of 10 sera. EDTA-separated skin expressed the 97-kD band in both epidermal (4 of 10 sera) and dermal (6 of 10 sera) extract. Immunoabsorption of positive sera with epidermis purified an IgA antibody that reacted uniquely with the 97-kD band. In addition, IgA antibody bound to nitrocellulose was eluted from the 97-kD band and found to uniquely bind basement membrane zone. It is likely that the 97-kD protein identified by these techniques is responsible for basement membrane binding of IgA in LABD.

Identification of the cutaneous basement membrane zone antigen and isolation of antibody in linear immunoglobulin A bullous dermatosis. J J Zone, T B Taylor, D P Kadunce, and L J Meyer. J Clin Invest. 1990 Mar; 85(3): 812–820. doi:  10.1172/JCI114508

 

Potassium Sorbate

Antimicrobial and physical properties of sweet potato starch films incorporated with potassium sorbate or chitosan

Abstract

Antimicrobial biodegradable films have been prepared with sweet potato starch by incorporating potassium sorbate or chitosan. Films incorporated with potassium sorbate ≥ 15% or chitosan ≥ 5% were found to have an anti-Escherichia coli effect. Staphylococcus aureus could be effectively suppressed by incorporation of chitosan at ≥10%. Whereas potassium sorbate lowers the tensile strength and elongation at break, and raises the oxygen permeability, water vapor permeability and water solubility, chitosan has the opposite effect. Fourier Transform Infrared (FT-IR) spectra analysis revealed that starch crystallinity was retarded by potassium sorbate incorporation and that hydrogen bonds were formed between chitosan and starch. This explained the modification of the mechanical and physical properties of the films by the incorporation of these two antimicrobial agents.

Antimicrobial and physical properties of sweet potato starch films incorporated with potassium sorbate or chitosan. Xiao Li Shena, Jia Min Wu, Yonghong Chen, Guohua Zhao. Food Hydrocolloids. Volume 24, Issue 4, June 2010, Pages 285–290. doi:10.1016/j.foodhyd.2009.10.003

 

Effect of potassium sorbate washing on the growth of Listeria monocytogenes on fresh poultry

Abstract

This work evaluated the effect of potassium sorbate washing on the growth of Listeria monocytogenes on poultry legs stored at 4 °C for 7 days. Fresh inoculated chicken legs were dipped into either a 2.5% (w/v) or 5% potassium sorbate solution or distilled water (control). Changes in mesophiles, pychrotrophic counts and sensorial characteristics (odor, color, texture and overall appearance) were also evaluated.

The shelf life of the samples washed with potassium sorbate was extended by at least 2 days over the control samples washed with distilled water. Legs washed with 5% potassium sorbate showed a significant (p < 0.05) inhibitory effect on L. monocytogenes compared to control legs, with a decrease of about 1.3 log units after 7 days of storage. Sensory quality was not adversely affected by potassium sorbate.

Effect of potassium sorbate washing on the growth of Listeria monocytogenes on fresh poultry. E. González-Fandos, J.L. Dominguez. Food Control. Volume 18, Issue 7, July 2007, Pages 842–846. doi:10.1016/j.foodcont.2006.04.008

 

Sorbic Acid and Potassium Sorbate Permeability of an Edible Methylcellulose-Palmitic Acid Film: Water Activity and pH Effects

ABSTRACT

The apparent permeability constants for potassium sorbate and sorbic acid through an edible film composed of methylcellulose and palmitic acid (weight ratio 3:1) were evaluated as a function of water activity (aw) and pH. For films with thickness 55–66 μm, potassium sorbate permeability increased from 2.3 × 10−10 to 2.0 × 10−8 (mg/sec cm2)(cm)/(mg/mL) as aw increased from 0.65 to 0.80. Films were not stable at aw levels above 0.80. Permeability of the film to sorbic acid at aw 0.8 decreased from 3.3 × 10−8 to 9.1 × 10−10 (mg/sec cm2)(cm)/ (mg/mL) as pH increased from 3 to 7. At pH 3 the undissociated acid was 97.5% and at pH 7 it was 0.4%.

RICO-PEÑA, D. C. and TORRES, J. A. (1991), Sorbic Acid and Potassium Sorbate Permeability of an Edible Methylcellulose-Palmitic Acid Film: Water Activity and pH Effects. Journal of Food Science, 56: 497–499. doi: 10.1111/j.1365-2621.1991.tb05312.x

 

Validation of HPLC Analysis of 2-Phenoxyethanol, 1-Phenoxypropan-2-ol, Methyl, Ethyl, Propyl, Butyl and Benzyl 4-Hydroxybenzoate (Parabens) in Cosmetic Products, with Emphasis on Decision Limit and Detection Capability

Abstract

The Commission Decision of August 12, 2002 on the performance of analytical methods and the interpretation of results was applied to the HPLC method for the analysis of parabens, 2-phenoxyethanol and 1-phenoxypropan-2-ol in cosmetic products. This method is published in the seventh Directive 96/45/EC of the European Commission. Non-compliant concentrations, taking into account the data distribution (CCα) and the probability of false negative values (CCβ) were determined. The repeatability and reproducibility amount to <4% and <7%, respectively. These values were obtained with blanc samples that were fortified in the laboratory. Calibration linearity was confirmed by absence of lack of fit for all seven preservatives. Matrix effects on the determinations of the preservatives in body milk or shampoo are negligible.

Validation of HPLC Analysis of 2-Phenoxyethanol, 1-Phenoxypropan-2-ol, Methyl, Ethyl, Propyl, Butyl and Benzyl 4-Hydroxybenzoate (Parabens) in Cosmetic Products, with Emphasis on Decision Limit and Detection Capability.

  1. Borremans , J. Van Loco, P. Roos, L. Goeyens. Chromatographia. January 2004, Volume 59, Issue 1, pp 47-53

 

Xanthan Gum

 

Xanthan gum: production, recovery, and properties

Abstract

Xanthan gum is a microbial polysaccharide of great commercial significance. This review focuses on various aspects of xanthan production, including the producing organismXanthomonas campestris, the kinetics of growth and production, the downstream recovery of the polysaccharide, and the solution properties of xanthan.

F Garcı́a-Ochoa, V.E Santos, J.A Casas, E Gómez Biotechnology Advances Volume 18, Issue 7, 1 November 2000, Pages 549–579. doi:10.1016/S0734-9750(00)00050-1

http://www.sciencedirect.com/science/article/pii/S0734975000000501

Antioxidative properties of xanthan on the autoxidation of soybean oil in cyclodextrin emulsion.

Antioxidative properties of xanthan on the autoxidation of soybean oil in cyclodextrin emulsion.

Kazuko. Shimada , Kuniko. Fujikawa , Keiko. Yahara , Takashi. Nakamura. J. Agric. Food Chem., 1992, 40 (6), pp 945–948. DOI: 10.1021/jf00018a005

 

Xanthan gum biosynthesis and application: a biochemical /genetic perspective

Abstract:

Xanthan gum is a complex exopolysaccharide produced by the plant-pathogenic bacteriumXanthomonas campestris pv. campestris. It consists of D-glucosyl, D-mannosyl, and D-glucuronyl acid residues in a molar ratio of 2:2:1 and variable proportions of O-acetyl and pyruvyl residues. Because of its physical properties, it is widely used as a thickener or viscosifier in both food and non-food industries. Xanthan gum is also used as a stabilizer for a wide variety of suspensions, emulsions, and foams. This article outlines aspects of the biochemical assembly and genetic loci involved in its biosynthesis, including the synthesis of the sugar nucleotide substrates, the building and decoration of the pentasaccharide subunit, and the polymerization and secretion of the polymer. An overview of the applications and industrial production of xanthan is also covered.

Xanthan gum biosynthesis and application: a biochemical /genetic perspective. A. Becker,F. Katzen, A. Pühler, L. Ielpi. Applied Microbiology and Biotechnology. August 1998, Volume 50, Issue 2, pp 145-152.

http://link.springer.com/article/10.1007/s002530051269

 

Intermolecular binding of xanthan gum and carob gum

Abstract.

Gels are a representative state for polysaccharides in both natural and artificial systems. The nature of the inter-chain associations within the junction zones is important and models for such interactions between like polysaccharides are based on X-ray diffraction studies of oriented gels. Here we describe the extension of such studies to a binary gel (xanthan-carob) in order to characterize for the first time intermolecular binding between different polysaccharides. Xanthan-carob binding has been proposed to explain gelation of the mixtures and as a model for host-pathogen recognition and adhesion of Xanthomonas bacteria within plant vascular systems. Our data suggest that the established model1–7 is incorrect and point to an alternative association mechanism.

 

Intermolecular binding of xanthan gum and carob gum. P. CAIRNS, M. J. MILES & V. J. MORRIS. Nature 322, 89 – 90 (03 July 1986); doi:10.1038/322089a0

http://www.nature.com/nature/journal/v322/n6074/abs/322089a0.html

 

Comparative study on xanthan gum and hydroxypropylmethyl cellulose as matrices for controlled-release drug delivery I. Compaction and in vitro drug release behaviour..

Abstract:

A comparative investigation has been undertaken to assess the performance of xanthan gum (XG) and hydroxypropylmethyl cellulose (HPMC) as hydrophilic matrix-forming agents in respect of compaction characteristics and in vitro drug release behaviour. The overall compaction characteristics are found to be quite similar to each other and typical of polymer behaviour. But the flow characteristics are different, i.e., XG is more readily flowable than HPMC. The observed difference in drug release profiles between these two potential excipients are explored and explained by the difference in their hydrophilicity and subsequent hydration properties.

Comparative study on xanthan gum and hydroxypropylmethyl cellulose as matrices for controlled-release drug delivery I. Compaction and in vitro drug release behaviour. Mohammad Mahiuddin Talukdar, Armand Michoel, Patrick Rombaut, Renaat Kinget. International Journal of Pharmaceutics.Volume 129, Issues 1–2, 8 March 1996, Pages 233–241. doi:10.1016/0378-5173(95)04355-1

 

Palmitoyl Oligopeptide Palmitoyl Tripeptide-7

 

Cosmeceuticals and peptides

Abstract

In nature, the majority of chemical reactions, biological responses, and regulatory processes are modulated in some part by specific amino acid sequences. The transfer of these interactive sequences and the biological activities they induce to short, stable, and readily synthesized peptides has created a diverse new field of modulating molecules applicable to dermatology and skin care industries. Areas such as inflammation, pigmentation, cell proliferation and migration, angiogenesis, innate immunity, and extracellular matrix synthesis have yielded peptide candidates for application to this area.

Zhang, Lijuan, and Timothy J. Falla. “Cosmeceuticals and peptides.” Clinics in dermatology 27.5 (2009): 485-494.

 

New and improved skin treatment systems

Abstract

A basic facial and body treatment cosmetic formulation is a combination of a cationic emulsifying agent, an oil soluble liquid polymer and a naturally occurring lactate buffer system. The basic formulation is a starter system that can be specialized to skin moisturizers, skin lighteners, skin pigmenting agents, sunscreens, antioxidants, line reducing products, wrinkle reducing products, anti-cellulite products, pharmaceuticals and the like.

Fox, Charles. “New and improved skin treatment systems.” U.S. Patent Application No. 11/810,878.

Bioactive peptides: signaling the future

Summary

Natural processes within the body are modulated almost exclusively by the interaction of specific amino acid sequences, either as peptides or as subsections of proteins. With respect to skin, proteins and peptides are involved in the modulation of cell proliferation, cell migration, inflammation, angiogenesis, melanogenesis, and protein synthesis and regulation. The creation of therapeutic or bioactive peptide analogs of specific interactive sequences has opened the door to a diverse new field of pharmaceutical and active cosmetic ingredients for the skincare industry. Here, we describe the origin of such sequences, their role in nature, their application to dermatology, as well as the advantages and challenges posed by this new technology.

Fields, K., et al. “Bioactive peptides: signaling the future.” Journal of cosmetic dermatology 8.1 (2009): 8-13.

 

Skin treatment systems

Abstract

A basic facial and body treatment cosmetic formulation is a combination of a cationic emulsifying agent, an oil soluble liquid polymer and a naturally occurring lactate buffer system. The basic formulation is a starter system that can be specialized to skin moisturizers, skin lighteners, skin pigmenting agents, sunscreens, antioxidants, line reducing products, wrinkle reducing products, anti-cellulite products, pharmaceuticals and the like.

Fox, Charles. “Skin treatment systems.” U.S. Patent No. 8,268,335. 18 Sep. 2012.

 

Tocopherol Acetate

Biokinetics in humans of RRR-α-tocopherol: The free phenol, acetate ester, and succinate ester forms of vitamin E

Abstract

The bioavailability of RRR-α-tocopherol from the oral administration of RRR-α-tocopherol itself and its acetate and succinate esters was determined in healthy human subjects. Venous blood samples were withdrawn periodically over a 51-h period following oral administration of a gelatin capsule containing an equimolar mixture of RRR-α-tocopherol and RRR-α-tocopheryl acetate. In a second study, subjects received a capsule containing an equimolar mixture of RRR-α-tocopheryl acetate and RRR-α-tocopheryl succinate. In Study 1, RRR-α-tocopherol was absorbed at similar rates from both the free phenol, and the acetate ester and maximum plasma levels occurred at 12 h in most subjects. The extent of absorption of RRR-α-tocopherol varied considerably between subjects in absolute terms, but the relative absorption from the two forms was remarkably consistent, and a ratio of 1.0 was found for parameters of relative bioavailability in plasma. The concentration of RRR-α-tocopherol from each form was maximal at approximately 27 h in red blood cells and, as seen with the plasma data, there was a large inter-individual variability. In Study 2, there was no significant difference in the extent of absorption of RRR-α-tocopherol from the acetate ester and the succinate ester, although there was an apparently higher initial rate of absorption from the acetate ester.

Biokinetics in humans of RRR-α-tocopherol: The free phenol, acetate ester, and succinate ester forms of vitamin E. Kevin H. Cheeseman, Anne E. Holley, Frank J. Kelly, Mohamad Wasil, Lise Hughes, Graham Burton. Free Radical Biology and Medicine.Volume 19, Issue 5, November 1995, Pages 591–598.doi:10.1016/0891-5849(95)00083-A

A novel sunscreen system based on tocopherol acetate incorporated into solid lipid nanoparticles

Synopsis Solid lipid nanoparticles (SLN) have been introduced as a novel carrier system for drugs and cosmetics. It has been found that SLN possess characteristics of physical UV-blockers on their own, thus offering the possibility of developing a more effective sunscreen system with reduced side-effects. Incorporation of the chemical sunscreen tocopherol acetate into SLN prevents chemical degradation and increases the UV-blocking capacity. Aqueous SLN dispersions were produced and incorporated into gels, followed by particle size examination, stability testing upon storage and thermoanalytical examination. Investigation of the UV-blocking capacity using different in vitro techniques revealed that the SLN dispersions produced in this study are at least twice as effective as their reference emulsions (conventional emulsions with identical lipid content). Placebo SLN even show greater UV-blocking efficacy than emulsions containing tocopherol acetate as the molecular sunscreen. Incorporation of tocopherol acetate into SLN leads to an overadditive UV-blocking effect. Furthermore, film formation of SLN on the skin and occlusivity were examined. The obtained data show that incorporation of tocopherol acetate into SLN leads to an improved sunscreen and skin care formulation.

Wissing, S. A. and Müller, R. H. (2001), A novel sunscreen system based on tocopherol acetate incorporated into solid lipid nanoparticles. International Journal of Cosmetic Science, 23: 233–243. doi: 10.1046/j.1467-2494.2001.00087.x

 

Preparation of core-shell PAN nanofibers encapsulated alpha-tocopherol acetate and ascorbic acid 2-phosphate for photoprotection

Preparation of core-shell PAN nanofibers encapsulated alpha-tocopherol acetate and ascorbic acid 2-phosphate for photoprotection. Wu, Xiao-Mei; Branford-White, Christopher J.; Yu, Deng-Guang; et al. COLLOIDS AND SURFACES B-BIOINTERFACES  Volume: 82 Issue: 1 Pages: 247-252

In vitro and in vivo Permeation of Vitamin E and Vitamin E Acetate from Cosmetic Formulations.

In vitro and in vivo Permeation of Vitamin E and Vitamin E Acetate from Cosmetic Formulations. Nada, Aly; Krishnaiah, Yellela S. R.; Zaghloul, Abdel-Azim; et al.MEDICAL PRINCIPLES AND PRACTICE  Volume: 20 Issue: 6 Pages: 509-513 Published: 2011

Chemoprevention of Human Actinic Keratoses by Topical DL-alpha-Tocopherol.

Chemoprevention of Human Actinic Keratoses by Topical DL-alpha-Tocopherol. Foote, Janet A.; Ranger-Moore, James R.; Einspahr, Janine G.; et al. CANCER PREVENTION RESEARCH  Volume: 2 Issue: 4 Pages: 394-400

A topical antioxidant solution containing vitamins C and E stabilized by ferulic acid provides protection for human skin against damage caused by ultraviolet irradiation.

A topical antioxidant solution containing vitamins C and E stabilized by ferulic acid provides protection for human skin against damage caused by ultraviolet irradiation. Murray, John C.; Burch, James A.; Streilein, Robert D.; et al.JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY  Volume: 59 Issue: 3 Pages: 418-425

Vitamin E in human skin: Organ-specific physiology and considerations for its use in dermatology.

Vitamin E in human skin: Organ-specific physiology and considerations for its use in dermatology. Thiele, Jens J.; Ekanayake-Mudiyanselage, Swarna. MOLECULAR ASPECTS OF MEDICINE  Volume: 28 Issue: 5-6 Pages: 646-667

 

Thyme Extract

Oregano, thyme and clove-derived flavors and skin sensitizers activate specific TRP channels

Carvacrol, eugenol and thymol are major components of plants such as oregano, savory, clove and thyme. When applied to the tongue, these flavors elicit a warm sensation. They are also known to be skin sensitizers and allergens. The transient receptor potential channel (TRPV3) is a warm-sensitive Ca2+-permeable cation channel highly expressed in the skin, tongue and nose. Here we show that TRPV3 is strongly activated and sensitized by carvacrol, thymol and eugenol. Tongue and skin epithelial cells respond to carvacrol and eugenol with an increase in intracellular Ca2+ levels. We also show that this TRPV3 activity is strongly potentiated by phospholipase C–linked, G protein–coupled receptor stimulation. In addition, carvacrol activates and rapidly desensitizes TRPA1, which may explain the pungency of oregano. Our results support a role for temperature-sensitive TRP channels in chemesthesis in oral and nasal epithelium and suggest that TRPV3 may be a molecular target of plant-derived skin sensitizers.

Oregano, thyme and clove-derived flavors and skin sensitizers activate specific TRP channels. Haoxing Xu, Markus Delling, Janice C Jun & David E Clapham. Nature Neuroscience 9, 628 – 635 (2006). doi:10.1038/nn1692

Effects of Thymus serpyllum Extract on Cell Proliferation, Apoptosis and Epigenetic Events in Human Breast Cancer Cells.

Effects of Thymus serpyllum Extract on Cell Proliferation, Apoptosis and Epigenetic Events in Human Breast Cancer Cells. Emir Bozkurt, Harika Atmaca, Asli Kisim, Selim Uzunoglu, Ruchan Uslu & Burcak Karaca. Nutrition and CancerVolume 64, Issue 8, November 2012, pages 1245-1250.

Rosemary (Rosmarinus officinalis L.) Extract as a Potential Complementary Agent in Anticancer Therapy.

Rosemary (Rosmarinus officinalis L.) Extract as a Potential Complementary Agent in Anticancer Therapy.Margarita González-Vallinas, Guillermo Reglero & Ana Ramírez de Molina. Nutrition and CancerVolume 67, Issue 8, November 2015, pages 1223-1231

The effects of essential oils and aqueous tea infusions of oregano (Origanum vulgare L. spp. hirtum), thyme (Thymus vulgaris L.) and wild thyme (Thymus serpyllum L.) on the copper-induced oxidation of human low-density lipoproteins.

The effects of essential oils and aqueous tea infusions of oregano (Origanum vulgare L. spp. hirtum), thyme (Thymus vulgaris L.) and wild thyme (Thymus serpyllum L.) on the copper-induced oxidation of human low-density lipoproteins.Tea Kulišić Ph.D, Anita Kriško, Verica Dragović-Uzelac, Mladen Miloš & Greta Pifat. International Journal of Food Sciences and Nutrition. Volume 58, Issue 2, January 2007, pages 87-93

Essential Oil of Thyme (Thymus vulgaris L.) Grown in Cuba

Essential Oil of Thyme (Thymus vulgaris L.) Grown in Cuba. Jorge A. Pino, Mirna Estarrón & Victor Fuentes. Journal of Essential Oil Research. Volume 9, Issue 5, September 1997, pages 609-61.

Chemical Profile, Antioxidant and Antibacterial Activity of Thyme and Oregano Essential Oils, Thymol and Carvacrol and Their Possible Synergism.

Chemical Profile, Antioxidant and Antibacterial Activity of Thyme and Oregano Essential Oils, Thymol and Carvacrol and Their Possible Synergism. Neda Gavaric, Sonja Smole Mozina, Nebojša Kladar & Biljana Bozin. Journal of Essential Oil Bearing Plants. Volume 18, Issue 4, July 2015, pages 1013-1021

Investigation of Extracts from Thyme (Thymus vulgaris L.) for Application in Cosmetics.

Investigation of Extracts from Thyme (Thymus vulgaris L.) for Application in Cosmetics. Stanka Damianova, Stanislava Tasheva, Albena Stoyanova & Dancho Damianov. Journal of Essential Oil Bearing Plants.Volume 11, Issue 5, January 2008, pages 443-450

Identification and quantification of a major anti-oxidant and anti-inflammatory phenolic compound found in basil, lemon thyme, mint, oregano, rosemary, sage, and thyme.

Identification and quantification of a major anti-oxidant and anti-inflammatory phenolic compound found in basil, lemon thyme, mint, oregano, rosemary, sage, and thyme. Jae B. Park. International Journal of Food Sciences and Nutrition. Volume 62, Issue 6, September 2011, pages 577-584

 

Citric Acid

 

Overview of citric acid production from Aspergillus niger.

Abstract

Citric acid has high economic potential owing to its numerous applications. It is mostly produced by microbial fermentation using Aspergillus niger. In view of surges in demand and growing markets, there is always a need for the discovery and development of better production techniques and solutions to improve production yields and the efficiency of product recovery. To support the enormous scale of production, it is necessary and important for the production process to be environmentally friendly by utilizing readily available and inexpensive agro-industrial waste products, while maintaining high production yields. This article reviews the biochemistry of citric acid formation, choices of citric-acid producing microorganisms and raw materials, fermentation strategies, the effects of various fermentation conditions, citric acid recovery options and the numerous applications of citric acid, based on information drawn from the literature over the past 10 years.

Overview of citric acid production from Aspergillus niger. Pau Loke Show, Kehinde Opeyemi Oladele, Qi Yan Siew, Fitri Abdul Aziz Zakry, John Chi-Wei Lan & Tau Chuan Ling. Frontiers in Life Science. Volume 8, Issue 3, July 2015, pages 271-283

 

Citric Acid-Ammonium Acetate Buffer.

Abstract

A pH table is reported for citric acid-ammonium acetate buffers that are useful for horseradish peroxidase (HRP) histochemistry.

Citric Acid-Ammonium Acetate Buffer. Sharon Stegmann, Robert B. Norgren & Michael N. Lehman. biotechnic & Histochemistry.Volume 66, Issue 1, January 1991, pages 27-28

 

Characterization of Blue Whiting Skin Gelatines Extracted After Pretreatment with Different Organic Acids.

Abstract

Gelatines were extracted from blue whiting (Micromesistius poutassou) skins after pretreatment with different organic acids (acetic, citric, lactic, malic, and tartaric acids). The effect of the pretreatment on the chemical composition and the rheological properties of extracted gelatines were analyzed. It was observed that acetic acid pretreatment resulted in significantly (p < 0.05) higher extraction yield compared to the rest of the gelatines. All gelatines, regardless of the organic acid used in the pretreatment, had similar chemical composition (p > 0.05). The amino acid analysis showed that acetic acid pretreated skins resulted in gelatines with higher imino acid levels with respect to the other pretreatments. Acetic and tartaric acid derived gelatine gels showed highly interconnected protein networks and better viscoelastic properties, in terms of storage modulus, compared to the other pretreatments.

Characterization of Blue Whiting Skin Gelatines Extracted After Pretreatment with Different Organic Acids. Zied Khiari, Daniel Rico, Ana Belen Martin-Diana & Catherine Barry-Ryan. Journal of Aquatic Food Product Technology. Volume 24, Issue 6, August 2015, pages 546-555

The direct determination of phosphorus in citric acid soil extracts by colorimetry and direct-current plasma emission spectroscopy.

 

Abstract

The effect of citrate interference on the direct colorimetric determination of P in 1% citric acid soil extracts of a wide range of soils was investigated and compared to that of removing the citric acid by dry ashing. It was found that dilution of the soil extracts to ratios greater than 1:20 caused minimal interference with colour development using the molybdenum blue method. Dilutions of 1:10 and 1:5 caused a 10% and 55% reduction in absorbance values respectively. Despite this interference, the measurement of P in the presence of 1% citric acid is possible if the same concentration of this acid, present in the soil extract, is present in the calibration standards. Generally a 1:10 dilution of soil extracts provides sufficient sensitivity for the determination of P in soils with a P status < 5 mg kg−1 and can accommodate soils with a P status up to 100 mg kg−1. The effect of dry ashing the soil extracts and measuring the P colorimetrically resulted in slightly higher P values, in the order of 2 mg kg−1. Similar results were obtained when the soil extracts were aspirated into a direct-current plasma and the P was measured by emission spectrometry. It was concluded that quantities of P could be present in the soil extracts, either organically or inorganically bound, and were responsible for this difference. These forms of P were not determined by colorimetric procedures but were released by a high-temperature plasma or by dry ashing. For most practical purposes these low values can be ignored.

The direct determination of phosphorus in citric acid soil extracts by colorimetry and direct-current plasma emission spectroscopy. G. R. Thompson. South African Journal of Plant and Soil. Volume 12, Issue 4, January 1995, pages 152-157

 

Development and evaluation of dual controlled release microballoons containing riboflavin and citric acid: in vitro and in vivo evaluation.

Abstract

The objective of this work was to optimize the incorporation of citric acid (CA) in the gastroretentive microballoons containing riboflavin (RF) in order to achieve dual controlled release system and consequently enhance the bioavailability of RF. Microballoons of 739 ± 1.9 µm containing RF–CA were prepared by modified emulsion solvent diffusion method and were evaluated both for in vitro and in vivo performance. RF–CA microballoons with 22.8% RF and 37.2% CA entrapped in the shell matrix composed of Eudragit® S 100 and HPMCK4M and in vitro buoyancy of 86.0 ± 0.88% (RCM3) was selected for further studies. RCM3 exhibited biphasic, pH-dependent in vitro dual controlled release of RF (0.9933–0.9962) and CA (0.996–0.9984) beyond 1 h in both simulated fasted and fed state conditions. RCM3 was able to achieve higher mean plasma concentrations than reference formulation RM2 (RF microballoon) both in fed and fasted states in rabbits. The mean AUC0–24 estimate of RCM3 was 55% higher in fasted state (p < 0.01) and about 51% higher in fed state (p < 0.05) relative to mean AUC0–24 from RM2 formulation. Conclusively, enhancement in RF in the presence of CA along the entire plasma level curve suggests a possibility of reduction in dosing frequency. This controlled release drug delivery system of RF, where CA is incorporated in the microballoons can be easily encapsulated in capsule dosage form negating the need of CA solution as vehicle for administration of RF microballoons.

Development and evaluation of dual controlled release microballoons containing riboflavin and citric acid: in vitro and in vivo evaluation. Amriteshwar N. Singh & Kamla Pathak. Journal of Microencapsulation. Volume 28, Issue 5, August 2011, pages 442-454

 

Chamomile (Matricaria recutita) Extract

CHAMOMILE (Matricaria recutita) EXTRACT AS A CORROSION INHIBITOR FOR MILD STEEL IN HYDROCHLORIC ACID SOLUTION

Abstract

The corrosion inhibition of mild steel in hydrochloric acid solution by chamomile (Matricaria recutita) extract (CE) was investigated through electrochemical (polarization, EIS) and surface analysis (optical microscopy/AFM/SEM) techniques. The effects of inhibitor concentration, temperature, and pH were evaluated. Thermodynamic parameters were calculated and adsorption studies were carried out. Finally, the surface morphology was investigated. The electrochemical studies showed that CE acts as a mixed-type corrosion inhibitor with predominantly anodic behavior. CE was adsorbed physically on the metal surface and obeyed the Langmuir adsorption isotherm. It impeded the corrosion processes by changing the activation energy. In the presence of CE, the metal surface was more uniform than the surface in the absence of inhibitor. Maximum inhibition efficiency (IE) was 93.28%, which was obtained at 22°C in 7.2 g/L of inhibitor in 1 M HCl solution.

CHAMOMILE (Matricaria recutita) EXTRACT AS A CORROSION INHIBITOR FOR MILD STEEL IN HYDROCHLORIC ACID SOLUTION. Mahdi Nasibi, Davood Zaarei, Gholamreza Rashed & Effat Ghasemi. Chemical Engineering Communications.Volume 200, Issue 3, March 2013, pages 367-378

 

Chamomile Ligulate Flowers in Supercritical CO2-Extraction

Abstract

The essential oil (EO) of chamomile ligulate flowers (CLF) was extracted by supercritical carbon dioxide (SC-CO2) at 240 bar and 40°C for five hours. An empirical equation: log c = a log W + b, for defining the dependence of total extract concentration (cTE), i.e. EO concentration (cEO) in supercritical CO2, on relative mass of CO2 (W) was selected. The equations obtained fitted the experimental data very well (r1=0.9997 and r2=0.9977). In the same way, the behavior of pharmacologically active chamomile compounds [(—)-α-bisabolol, oxides A and B, (—)-α-bisabolol, cis- and trans-en-in-dicycloethers] contained in EO of CLF after SC-CO2 extraction, was investigated. For qualitative and quantitative determination of EOs the GC/MS analysis was used. The fermentation of CLF after SC-CO2 extraction was used to increase the content of spasmolytically important chamomile flavone apigenin. The procedure of obtaining the product of CLF with the best composition of pharmacologically active compounds of chamomile has been reported.

Chamomile Ligulate Flowers in Supercritical CO2-Extraction. Zoran P. Zekovic. Journal of Essential Oil Research. Volume 12, Issue 1, January 2000, pages 85-93

 

Antioxidant Activity, Reaction Mechanisms, and Kinetics of Matricaria recutita Extract in Commercial Blended Oil Oxidation.

Abstract

Antioxidant activity, reaction mechanisms, and kinetics of Matricaria recutita crude extract (CE; total phenolics: 41 ± 2.5 mg/g, total flavonoids: 26 ± 1.4 mg/g, IC50: 82.3 ± 2.8 µg/mL and reducing power: 10.45 ± 0.56 mmol Fe2+/mass) in comparison to tert-Butylhydroquinone during oxidation of blended vegetable oil (sunflower, soybean, and palm oil) at 120, 130, and 140°C were studied. Good correlations existed between the Rancimat oil stability index and stability indices (induction period) calculated from peroxide value, conjugated diene value, and anisidine value with no significant differences in kinetic parameters calculated from them. The temperature acceleration (Q10), activation energy (Ea), frequency factor (A), enthalpy (ΔH++), entropy (ΔS++), and free energy of activation (ΔG++) for oils containing crude extract were lower than for oils containing tert-Butylhydroquinone (0.0025, 0.005, 0.01, and 0.02%). Values were independent of crude extract or tert-Butylhydroquinone concentration. For crude extract and tert-Butylhydroquinone, Ea and A were well correlated with ΔH++ and ΔS++ values, respectively, but correlation between Ea and Q10 for crude extract compared to tert-Butylhydroquinone was poor. Furthermore, the rate of Monounsaturated:Polyunsaturated fatty acids formation did not differ significantly between crude extract and tert-Butylhydroquinone, but concentrations of them did affect Monounsaturated:Polyunsaturated ratio. Based on the results obtained, crude extract decreased the rate of the oxidation reaction due to the decrease in the concentration of the activated complex and reduction in the rate at which the activated complex dissociated into oxidation products.

Antioxidant Activity, Reaction Mechanisms, and Kinetics of Matricaria recutita Extract in Commercial Blended Oil Oxidation. Seyed Mohammad Bagher Hashemi, Mary Susan Brewer, Javad Safari, Masoud Nowroozi, Moosa Hamid Abadi Sherahi, Behrooz Sadeghi & Moslem Ghafoori. International Journal of Food PropertiesVolume 19, Issue 2, February 2016, pages 257-271

 

Chemical Composition and Antimicrobial Activity of Essential Oil of Matricaria recutita

Abstract

Matricaria recutita is a herbaceous plant belonging to the Asteraceae family. The present study reports the chemical composition and antimicrobial activity of M. recutita essential oil and its main compounds. The essential oil was obtained from the aerial parts of the M. recutita by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The major components were α-bisabolol oxide (38%), followed by camphene (9.11%), sabinene (4.87%), limonene (6%),1,8-cineole (7.12%), camphor (6.54%), and α-pinene (6%). Essential oil of chamomile was evaluated for its antibacterial activities against three gram-positive and four gram-negative pathogenic bacteria. The essential oil and its main compounds were particularly active against Bacillus cereus, with the lowest minimum inhibitory concentration and minimum bactericidal concentration value (0.022 and 1.5 μg /mL). In conclusion, these results support the use of the essential oil and its main compounds for their antimicrobial properties.

Chemical Composition and Antimicrobial Activity of Essential Oil of Matricaria recutita. Mohsen Kazemi. International Journal of Food Properties. Volume 18, Issue 8, August 2015, pages 1784-1792

Passion Flower (Passiflora Incarnata) Extract

 

Analyses of Passiflora Compounds by Chromatographic and Electrophoretic Techniques

Abstract

Passiflora is one of the 27 genera of the Passifloraceae family. Some Passiflora species are known by their edible fruits, which have a distinct flavor and aroma that favor their in natura consumption and their applicability in the food industry. Also, Passiflora leaves have therapeutical properties, such as the widely known anxiolytic and sedative effects. The quality control and the assessment of the compounds responsible for the Passiflora properties can be done by several chromatographic and electrophoretic techniques, such as planar chromatography (TLC and HTPLC), liquid chromatography (HPLC and UHPLC), gas chromatography (GC), and capillary electrophoresis (CE). The aim of this article is to review the analytical techniques used for the evaluation of the different compounds present in each part of a Passiflora plant, exploring the leaves, the fruits with their rinds and seeds, and other Passiflora parts, such as nectar and callus culture compositions, as well as to compare stability tests on several Passiflora products.

Analyses of Passiflora Compounds by Chromatographic and Electrophoretic Techniques. Gisláine C. Silva & Carla B. G. Bottoli. Critical Reviews in Analytical Chemistry. Volume 45, Issue 1, January 2015, pages 76-95

An Evidence-Based Systematic Review of Passion Flower (Passiflora Incarnata L.) by the Natural Standard Research Collaboration

An Evidence-Based Systematic Review of Passion Flower (Passiflora Incarnata L.) by the Natural Standard Research Collaboration. Journal of Dietary SupplementsVolume 5, Issue 3, January 2008, pages 310-340. DOI:10.1080/19390210802414360

 

Analyses of Passiflora Compounds by Chromatographic and Electrophoretic Techniques

Abstract

Passiflora is one of the 27 genera of the Passifloraceae family. Some Passiflora species are known by their edible fruits, which have a distinct flavor and aroma that favor their in natura consumption and their applicability in the food industry. Also, Passiflora leaves have therapeutical properties, such as the widely known anxiolytic and sedative effects. The quality control and the assessment of the compounds responsible for the Passiflora properties can be done by several chromatographic and electrophoretic techniques, such as planar chromatography (TLC and HTPLC), liquid chromatography (HPLC and UHPLC), gas chromatography (GC), and capillary electrophoresis (CE). The aim of this article is to review the analytical techniques used for the evaluation of the different compounds present in each part of a Passiflora plant, exploring the leaves, the fruits with their rinds and seeds, and other Passiflora parts, such as nectar and callus culture compositions, as well as to compare stability tests on several Passiflora products.

Analyses of Passiflora Compounds by Chromatographic and Electrophoretic Techniques. Gisláine C. Silva & Carla B. G. Bottoli. Critical Reviews in Analytical Chemistry. Volume 45, Issue 1, January 2015, pages 76-95

 

Hydrolyzed Silk Protein

Long-range periodic sequence of the cement/silk protein of Stenopsyche marmorata: purification and biochemical characterisation

Abstract

The long-range periodic amino acid sequence of the bifunctional silk/cement protein from larvae of the caddisfly, Stenopsyche marmorata, is discussed in this study. The protein, named the S. marmorata silk protein (Smsp-1), was first purified to electrophoretic homogeneity. The results of Edman-based sequencing of Smsp-1 tryptic digests were consistent with the amino acid sequence deduced from a cDNA clone of the Smsp-1 gene. All undetected amino acids in the Edman-based sequencing were encoded as Ser, suggesting the presence of O-phospho-Ser. 31P-NMR and an O-phospho-amino acid analysis successfully showed that the O-phospho-Ser residue occurred in a clustered manner, serving a cement function for Smsp-1. Two patterns of non-phosphorylated repeats, –SLGPYGDPRGDXLGPYGG– (X = V, G or D) and –GVGPYGDGLGPYGG–, were enriched in Smsp-1 compared with the O-phospho-Ser cluster, and have fibre-forming functions.

Long-range periodic sequence of the cement/silk protein of Stenopsyche marmorata: purification and biochemical characterisation. Kousaku Ohkawa, Yumi Miura, Takaomi Nomura, Ryoichi Arai, Koji Abe, Masuhiro Tsukada & Kimio Hirabayashi. BiofoulingVolume 29, Issue 4, April 2013, pages 357-367

 

Complexation-triggerable liposome mixed with silk protein and chitosan

Abstract

Complexation-triggerable liposomes were prepared by modifying the surface of egg phosphatidylcholine (EPC) liposomes with hydrophobicized silk fibroin (HmSF) and hydrophobicized chitosan (HmCh). Maximum complexation, determined by measuring the diameter of complexation, was found when the ratio of HmSF to HmCh was 14:1, so they were immobilized on the surface of liposomes at the same ratio. The degree of fluorescence quenching of calcein in liposomal suspension was as high as 68% when the ratio of surface modifier (HmSF + HmCh) to EPC was 1:15. When the ratio was increased to 1:5, the degree of quenching decreased to 32%, indicating the inefficient formation of liposome. Liposome mixed with the surface modifier was multi-lamellar vesicle on TEM photo. And, the mean diameter was larger than those of liposome mixed with either HmSF or HmCh, possibly due to insoluble complex on the liposomal surface. The liposome exhibited a pH-sensitive release and triggered the release at pH 5.5 and 6.0. It is believed that complexation is responsible for the promoted release at those pH values.

Complexation-triggerable liposome mixed with silk protein and chitosan.Yeon-Ji Hong & Jin-Chul Kim. Journal of Biomaterials Science, Polymer Edition. Volume 26, Issue 12, August 2015, pages 766-779

 

High-strength silk protein scaffolds for bone repair

Abstract

Biomaterials for bone tissue regeneration represent a major focus of orthopedic research. However, only a handful of polymeric biomaterials are utilized today because of their failure to address critical issues like compressive strength for load-bearing bone grafts. In this study development of a high compressive strength (~13 MPa hydrated state) polymeric bone composite materials is reported, based on silk protein-protein interfacial bonding. Micron-sized silk fibers (10–600 µm) obtained utilizing alkali hydrolysis were used as reinforcement in a compact fiber composite with tunable compressive strength, surface roughness, and porosity based on the fiber length included. A combination of surface roughness, porosity, and scaffold stiffness favored human bone marrow-derived mesenchymal stem cell differentiation toward bone-like tissue in vitro based on biochemical and gene expression for bone markers. Further, minimal in vivo immunomodulatory responses suggested compatibility of the fabricated silk-fiber-reinforced composite matrices for bone engineering applications.

High-strength silk protein scaffolds for bone repair. Biman B. Mandala, Ariela Grinberga, Eun Seok Gila, Bruce Panilaitisa, and David L. Kaplan. PNAS. May 15, 2012 vol. 109 no. 20. doi: 10.1073/pnas.1119474109

 

Applications of natural silk protein sericin in biomaterials

Abstract

Silk sericin is a natural macromolecular protein derived from silkworm Bombyx mori. During the various stages of producing raw silk and textile, sericin can be recovered for other uses. Also, sericin recovery reduces the environmental impact of silk manufacture. Sericin protein is useful because of its properties. The protein resists oxidation, is antibacterial, UV resistant, and absorbs and releases moisture easily. Sericin protein can be cross-linked, copolymerized, and blended with other macromolecular materials, especially artificial polymers, to produce materials with improved properties. The protein is also used as an improving reagent or a coating material for natural and artificial fibers, fabrics, and articles. The materials modified with sericin and sericin composites are useful as degradable biomaterials, biomedical materials, polymers for forming articles, functional membranes, fibers, and fabrics.

Applications of natural silk protein sericin in biomaterials. Yu-Qing Zhang. Biotechnology Advances. Volume 20, Issue 2, May 2002, Pages 91–100. doi:10.1016/S0734-9750(02)00003-4

Preparation of silk protein sericin as mitogenic factor for better mammalian cell culture.

We previously reported that sericin small (sericin-S), with a molecular weight that ranges from 5 to 100 kDa, is a cell culture supplement used to accelerate cell proliferation. In this study, a novel preparation method for sericin and several applications of sericin were examined. Sericin large, prepared under nonhydrolyzing conditions and ranging from 50 to 200 kDa, also accelerated cell proliferation, but its effects were inferior to those of sericin-S. Additional sericin preparations with various molecular weights that were differentially hydrolyzed were also tested but none of them was significantly superior to sericin-S, and neither were several recombinant sericin peptides. Sericin-S successfully accelerated the proliferation of hybridoma cells in various serum-free media, implying the mitogenic effect of sericin is independent from media. We also demonstrated that sericin-S successfully induced the proliferation of CTLL-2, an established T lymphocyte cell line, under IL-2 starvation conditions. These results indicate that sericin, particularly sericin-S, improves serum-free mammalian cell culture.

Preparation of silk protein sericin as mitogenic factor for better mammalian cell culture. Satoshi Terada, Masahiro Sasaki, Kana Yanagihara, Hideyuki Yamada. Journal of Bioscience and Bioengineering. Volume 100, Issue 6, December 2005, Pages 667–671.doi:10.1263/jbb.100.667

 

Expression and Purification of a Spider Silk Protein: A New Strategy for Producing Repetitive Proteins

Abstract

Synthetic genes were constructed based on the known sequence of the spider dragline silk protein MaSp 2. The genes had 8, 16, or 32 contiguous units of the consensus repeat sequence of the protein. These artificial genes were constructed using a strategy involving compatible but nonregenerable restriction sites, which allowed construction of very large inserts in a precisely controlled manner. This strategy should have general utility in the controlled construction of repetitive proteins composed of identical or different repeat units. The protein from the 16-unit repeat was produced inEscherichia coliat levels up to 10 mg/g wet wt of cells although yields of 1–2 mg/g were more typical. The protein was easily purified with high recovery using an affinity column. The purified protein had the predicted amino acid composition and N-terminal sequence after cleavage of a leader sequence. The methodology described will allow production of sufficient quantities of protein for basic structure/function studies including production of synthetic fibers.

Expression and Purification of a Spider Silk Protein: A New Strategy for Producing Repetitive Proteins. Randolph V. Lewisa, Michael Hinman, Srinivas Kothakota, Maurille J. Fournier. Protein Expression and Purification. Volume 7, Issue 4, June 1996, Pages 400–406.doi:10.1006/prep.1996.0060

 

Ascorbic Acid (Vitamin C)

 

Protective effect against sunburn of combined systemic ascorbic acid (vitamin C) and d-α-tocopherol (vitamin E)

Abstract

Background: UV radiation causes acute adverse effects like sunburn, photosensitivity reactions, or immunologic suppression, as well as long-term sequelae like photoaging or malignant skin tumors. UV radiation induces tissues to produce reactive oxygen species, eicosanoids and cytokines. Inhibition of these mediators might reduce skin damage. Antioxidants such as ascorbic acid and d-α-tocopherol have been found to be photoprotective in some in vitro studies and animal experiments. Objective: Our purpose was to assess the protective effect of systemic vitamins C and E against sunburn in human beings. Methods: In a double-blind placebo-controlled study, each of 10 subjects took daily either 2 gm of ascorbic acid (vitamin C) combined with 1000 IU of d-α-tocopherol (vitamin E) or placebo. The sunburn reaction before and after 8 days of treatment was assessed by determination of the threshold UV dose for eliciting sunburn (minimal erythema dose [MED]) and by measuring the cutaneous blood flow of skin irradiated with incremental UV doses against that of nonirradiated skin. Results: The median MED of those taking vitamins increased from 80 to 96.5 mJ/cm2 (p < 0.01), whereas it declined from 80 to 68.5 mJ/cm2 in the placebo group. Cutaneous blood flow changed significantly (p < 0.05) for most irradiation doses with decreases in those given vitamins and increases in the placebo group. Conclusion: Combined vitamins C and E reduce the sunburn reaction, which might indicate a consequent reduced risk for later sequelae of UV-induced skin damage. The increase of sunburn reactivity in the placebo group could be related to “priming” by the previous UV exposure. (J Am Acad Dermatol 1998;38:45-8.)

Eberlein-König, Bernadette, Marianne Placzek, and Bernhard Przybilla. “Protective effect against sunburn of combined systemic ascorbic acid (vitamin C) and d-α-tocopherol (vitamin E).” Journal of the American Academy of Dermatology 38.1 (1998): 45-48.

 

Topical ascorbic acid on photoaged skin. Clinical, topographical and ultrastructural evaluation: double‐blind study vs. placebo

Abstract

Abstract: Vitamin C is known for its antioxidant potential and activity in the collagen biosynthetic pathway. Photoprotective properties of topically applied vitamin C have also been demonstrated, placing this molecule as a potential candidate for use in the prevention and treatment of skin ageing.

A topically applied cream containing 5% vitamin C and its excipient were tested on healthy female volunteers presenting with photoaged skin on their low‐neck and arms in view to evaluate efficacy and safety of such treatment. A double‐blind, randomized trial was performed over a 6‐month period, comparing the action of the vitamin C cream vs. excipient on photoaged skin. Clinical assessments included evaluation at the beginning and after 3 and 6 months of daily treatment. They were performed by the investigator and compared with the volunteer self assessment. Skin relief parameters were determined on silicone rubber replicas performed at the same time‐points. Cutaneous biopsies were obtained at the end of the trial and investigated using immunohistochemistry and electron microscopy. Clinical examination by a dermatologist as well as self‐assessment by the volunteers disclosed a significant improvement, in terms of the ‘global score’, on the vitamin C‐treated side compared with the control. A highly significant increase in the density of skin microrelief and a decrease of the deep furrows were demonstrated. Ultrastructural evidence of the elastic tissue repair was also obtained and well corroborated the favorable results of the clinical and skin surface examinations.

Topical application of 5% vitamin C cream was an effective and well‐tolerated treatment. It led to a clinically apparent improvement of the photodamaged skin and induced modifications of skin relief and ultrastructure, suggesting a positive influence of topical vitamin C on parameters characteristic for sun‐induced skin ageing.

Humbert, Philippe G., et al. “Topical ascorbic acid on photoaged skin. Clinical, topographical and ultrastructural evaluation: double‐blind study vs. placebo.” Experimental Dermatology 12.3 (2003): 237-244.

 

Topical vitamin C protects porcine skin from ultraviolet radiation‐induced damage

Abstract

Summary Ultraviolet radiation damage to the skin is due, in part, to the generation of reactive oxygen species. Vitamin C (l‐ascorbic acid) functions as a biological co‐factor and antioxidant due to its reducing properties. Topical application of vitamin C has been shown to elevate significantly cutaneous levels of this vitamin in pigs, and this correlates with protection of the skin from UVB damage as measured by erythema and sunburn cell formation. This protection is biological and due to the reducing properties of the molecule. Further, we provide evidence that the vitamin C levels of the skin can be severely depleted after UV irradiation, which would lower this organ’s innate protective mechanism as well as leaving it at risk of impaired healing after photoinduced damage. In addition, vitamin C protects porcine skin from UVA‐mediated phototoxic reactions (PUVA) and therefore shows promise as a broad‐spectrum photoprotectant.

Darr, D., et al. “Topical vitamin C protects porcine skin from ultraviolet radiation‐induced damage.” British Journal of Dermatology 127.3 (1992): 247-253.

 

Topical melatonin in combination with vitamins E and C protects skin from ultraviolet-induced erythema: a human study in vivo.

Abstract

In this randomized, double-blind human study, the short-term photoprotective effects of different antioxidants and their combinations were evaluated in vivo. Vitamin C (ascorbic acid), vitamin E (alpha-tocopherol) and melatonin (N-acetyl-5-methoxytryptamine) were topically applied, alone or in combination, 30 min before ultraviolet-irradiation of the skin. The erythemal reaction was evaluated visually and non-invasively using different bioengineering methods (skin colour and skin blood flow). The results showed a modest protective effect of the vitamins when applied alone and a dose-dependent photoprotective effect of melatonin. Topical application of combinations of both vitamins, or of melatonin with vitamins, enhanced the photoprotective response. Better protection was obtained by using the combination of melatonin with both vitamins. The role of reactive oxygen species and oxygen-derived free radicals, as well as potential sunscreening properties of the employed antioxidants, are discussed in view of possible mechanisms to explain this elevated photoprotective effect.

Darr, D., et al. “Topical vitamin C protects porcine skin from ultraviolet radiation‐induced damage.” British Journal of Dermatology 127.3 (1992): 247-253.

 

Antioxidant activity of fresh apples

Abstract

Vitamin C is used as a dietary supplement because of its antioxidant activity, although a high dose (500 mg) may act as a pro-oxidant in the body1,2. Here we show that 100 g of fresh apples has an antioxidant activity equivalent to 1,500 mg of vitamin C, and that whole-apple extracts inhibit the growth of colon- and liver- cancer cells in vitro in a dose-dependent manner. Our results indicate that natural antioxidants from fresh fruit could be more effective than a dietary supplement.

Eberhardt, Marian V., Chang Yong Lee, and Rui Hai Liu. “Nutrition: Antioxidant activity of fresh apples.” Nature 405.6789 (2000): 903.
Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin

Ferulic acid is a potent ubiquitous plant antioxidant. Its incorporation into a topical solution of 15% L-ascorbic acid and 1% α-tocopherol improved chemical stability of the vitamins (C+E) and doubled photoprotection to solar-simulated irradiation of skin from 4-fold to approximately 8-fold as measured by both erythema and sunburn cell formation. Inhibition of apoptosis was associated with reduced induction of caspase-3 and caspase-7. This antioxidant formulation efficiently reduced thymine dimer formation. This combination of pure natural low molecular weight antioxidants provides meaningful synergistic protection against oxidative stress in skin and should be useful for protection against photoaging and skin cancer.

Lin, Fu-Hsiung, et al. “Ferulic acid stabilizes a solution of vitamins C and E and doubles its photoprotection of skin.” Journal of Investigative Dermatology 125.4 (2005): 826-832.