J. Cosmet. Sci.J 59, 73-75 CTanuary/February 2008) Abstracts International Journal of Cosmetic Science Vol. 29, No 5, 2007* Review Article: Nanostructure of the stratum comeum extracellular lipid matrix as observed by cryo-electron microscopy of vitreous skin sections L. Norlen Department of Cellular and Molecular Biology (CMB), Medical Nobel Institute, Karolinska Institute, Stockholm and Dennatology Clinic, Karolinska University Hospital, Stockholm, Sweden Lars Norlen, Department of Cellular and Molecular Biology (CMB), Medical Nobel Institute, Karolinska Institute, Stockholm, Sweden. Tel.: +46 8524 8758 fax: +46 831 3529 e-mail: Jars.norlen@ki.se In recent years, high-resolution cryo-electron microscopy of vitreous skin sections has been used to visualize the formation and structure of the human stratum comeum extracellular lipid matrix. The aim of the present work was to summarize these findings. It is proposed that skin barrier formation does not take place as a 'lamellar body' fusion process, but as a lamellar 'unfolding' of a small lattice parameter lipid 'phase' with cubic-like symmetry with subsequent 'crystallization' and concomitant lamellar re­ organization of the extracellular lipid matrix. In vitro stability of triclosan in dentifrice under simulated use condition Z. Hao, B. Parker and M. Knapp Global Analytical Sciences Department, Technology Center, Colgate-Palmolive Company, 909 River Rd, Piscataway, NJ 08855, U.S.A. Zhigang Hao, Global Analytical Sciences Department, Technology Center, Colgate-Palmolive Company, 909 River Rd, Piscataway, NJ 08855, U.S.A. Tel.: +l 732 878 6218 fax: +1 732 878 6138. e-mail: Zhigang hao@colpal.com Triclosan has been fonnulated into a dentifrice at a 0.3% level to enhance the antibacterial function of the dentifrice, to improve oral health and to decrease the daily malodor inside the mouth cavity. The hypothesis that chlorofonn may be generated from triclosan when contacted with chlorinated drinking water has challenged our guarantee of safe use of triclosan in oral care products, especially in Colgate Total® toothpaste. Currently, there was no available analytical method to detect chloroform levels under the use conditions expected during daily tooth brushing. To fill this gap and to continue guaranteeing that our customers can safely use Colgate Total® toothpaste products, a gas chromatography-single ion monitoring­ mass spectrometry method for detecting chloroform in artificial saliva media has been developed. The limit of detection (LOO) and limit of quantitation are about 41 and 130 ppb, respectively. This LOO level is lower than the current Environmental Protection Agency trihalomethanes contamination limit, which is required for our daily drink water. Our in vitro study indicated that Colgate Total® does not form detectable chlorofonn levels ( 41 ppb) over the range of expected consumer-brushing times while using normal chlorinated drinking water. In vitro skin permeation and retention of parabens from cosmetic formulations S. Pedersen1, F. Marra, S. Nicoli and P. Santi Dipartimento Farmaceutico, University of Panna, Parco rea delle Scienze, 43100 Panna, Italy P. Santi, Dipartimento Fannaceutico, University of Parma, Parco Area delle Scienze, 43100 Panna, Italy. Tel.: +39 0521 905069 fax: +39 0521 905006 e-mail: patrizia.santi@unipr.it 1 Present address: Department of Pharmaceutics, School of Pharmacy, University of Oslo, Oslo, Norway. Parabens are antimicrobial agents widely used in foods, cosmetics and pharmaceutical products. Although non­ mutagenic, non-teratogenic and non-carcinogenic, parabens * These abstracts appear as they were originally published. They have not been edited by the journal of Cosmetic Science. 73

74 JOURNAL OF COSMETIC SCIENCE can induce allergic contact dermatitis and posses estrogenic activity. The aim of this work was to assess the skin permeation and retention of methyl- (MP), ethyl- (EP) and propyl- (PP) paraben from three commercial cosmetic creams. The results obtained indicate that parabens are capable of permeating through and accumulating in the skin. The extent of penetration depends more on paraben characteristics (solubility, lipophilicity) than on the composition of the formulation. In particular, the percentage permeated across the skin was independent of the composition of the cream used and decreased in the order MP, EP and PP, in accordance with decreasing solubility. After 8 h of contact with the skin, 60% of MP, 40% of EP and 20% of PP were found across the skin. Concerning skin retention, the percentage remaining in the skin after 8 h depends on both paraben characteristics and on the composition of the formulation used. In conclusion, it appears that only the type of paraben, in particular its water solubility, affects skin penetration whereas the composition of the emulsion, which influences skin retention, plays a secondary role. Finally, excised rabbit ear skin can be considered as a good model for human skin for in vitro experiments. Fragrance raw materials and essential oils can reduce prostaglandin E2 formation in keratinocytes and reconstituted human epidermis Andreas Natsch and Michael Wasescha Givaudan Schweiz AG, Ueberlandstr. 138, CH-8600 Dubendorf, Switzerland Andreas Natsch, Givaudan Schweiz AG, Ueberlandstr. 138, CH-8600 Dubendorf, Switzerland. Tel.: +41(0)44 824 2105 fax: +41(0)44 824 2926 e-mail: andreas.natsch@givaudan.com Essential oils and certain perfumery raw materials exhibit a wide range of beneficial biological activities. Besides the antimicrobial and antioxidant activity, the anti­ inflammatory and anti-irritant effects are most often cited. One specific mode of action is the reduction of the formation of the key mediator prostaglandin E2 (PGE2). To study this activity in detail and to create cosmetically useful fragrances with the potential to reduce a key marker of skin irritancy in keratinocytes, an initial screening with pig blood platelets was conducted on 900 perfumery raw materials. Active compounds were then validated in a human keratinocyte cell line. Compounds which successfully reduced PGE2 formation in this assay were used for the creation of active fragrances. These final fragrances reduced PGE2 formation by 80% when dosed at 0.8 µg ml-, to keratinocytes. Application of such a fragrance in a hydrogel allowed reduction of UVB-induced PGE2 formation in reconstituted epidermis (MatTec EpiDerm™). Similarly, antiperspirant-induced formation of PGEz in reconstituted epidermis was reduced to background levels if these novel fragrances were used in the antiperspirant formulation. In conclusion, fragrances with this added cosmetic benefit can be created based on a database from a comprehensive screening. These fragrances may find use as a part of a formulation strategy optimizing each part of a cosmetic formulation for optimal product mildness. Emulsifying power of mannan and glucomannan produced by yeasts M. Kuncheva*, K. Pavlovat, I. Panchev* and S. Dobrevat *University of Food Technologies, Department of Organic Chemistry, 26 Maritza Blvd., 4002 Plovdiv, Laboratory of Applied Microbiology, Institute of Microbiology, Bulgarian Academy of Science, 26 Maritza Blvd., 4002 Plovdiv and tBulgarian Cosmetologists Association, 4002 Plovdiv, Bulgaria Ivan Panchev, University of Food Technologies, Department of Physics, 26 Maritza Blvd., 4002 Plovdiv, Bulgaria. Tel.: +359 32 603 715 fax: +359 32 644 102 e­ mail: ivanpanchev@hotmail.com Subject of study was the colloid chemical properties of the biopolymers mannan, synthesized from strain Rhodotorula acheniorum MC, and glucomannan, synthesized from strain Sporobolomyces salmonicolor AL,. Their emulsifying capacity was studied in model systems of aqueous solutions in concentrations from 0.5% to 2.5% with regard to the aqueous phase. Emulsions of the direct type ( oil/water) with 50% oil content were obtained. A disperse system with 2.5% glucomannan had 100% intact emulsion in the centrifugation test, while for the system with mannan, this indicator was 72%. Lab cream emulsions were obtained with glucomannan and with the emulsifiers Rofetan N/NS and Arlacel 165 used in the cosmetics industry. It has been established that under standard testing conditions, cream­ like emulsions with 2.0% glucomannan have stability indicators comparable to these of 5.0% rofetan N/NS and 5.0% Arlacel 165. The samples with different concentrations of glucomannan showed a pseudo-plastic behaviour, as the highest viscosity was shown by the emulsion with 2.0% stored at 45°C. The newly synthesized exopolysaccharides had a distinct emulsifying power and can be applied in the cosmetic and food industries. A double-blind and controlled study on the influence of the vehicle on the skin susceptibility to stinging from lactic acid A Sahlin*, F. Edlund t and M. Lodent *School of Biotechnolo � , Royal Institute of Technology, Stockholm, Sweden and ACO Hud Nordic AB, Upplands Vasby, Sweden Marie Loden, ACO Hud Nordic AB, Box 622, SE-194 26 Upplands Vasby, Sweden. Tel.: +46 708285832 e-mail: marie. loden@aconordic.com For patients with skin diseases, the process of treating the skin with topical medications adds to the burden of having the disease. Inconvenient skin reactions can make the treatment troublesome and lower the compliance. Moreover, epidemiological surveys indicate that 50% or more of female consumers believe they have sensitive skin. In the present study, the influence of the vehicle on the adverse skin reaction to lactic acid was judged by the test subjects after application of the test formulations to the facial skin. The results showed a water-in-oil (w/o) emulsion to induce less stinging than an ordinary oil-in­ water (o/w) emulsion. Increasing the mineral oil content in the o/w emulsion from 10% to 50% tended (P = 0.077) to decrease the stinging potential of the formulation. An o/w