JOURNAL OF COSMETIC SCIENCE 52 1 Authors present address: DermPharCos, Witts Park 16, 22587 Hamburg, Germany. With the advancement of skin research, today’s consumer has increased access to technological information about ageing skin and hair care products. As a result, there is a rapidly increasing demand for proof of effi cacy of these products. Recognizing these demands has led to the development and validation of many clinical methods to measure and quantify ageing skin and the effects of anti-ageing treatments. Many of the current testing methods used to research and evaluate anti-ageing product claim to employ sophisticated instruments alongside more traditional clinical methods. Intelligent use of combined clinical methods has enabled the development of technologically advanced consumer products providing enhanced effi cacy and performance. Of non-invasive methods for the assessment and quantifi cation of ageing skin, there is a plethora of tools available to the clinical researcher as defi ned by key clinically observed ageing parameters: skin roughness and surface texture fi ne lines and wrinkles skin pigmentation skin colour, fi rmness and elasticity hair loss and proliferative lesions. Furthermore, many clinical procedures for the evaluation of ageing skin treatments are combined with invasive procedures, which enable added-value to claims (such as identifi cation and alteration of biochemical markers), particularly in those cases where perception of product effect needs additional support. As discussed herein, clinical methods used in the assessment of skin ageing are many and require a disciplined approach to their use in such investigations. The perception threshold measurement can be a useful tool for evaluation of sensitive skin S.-J. Kim*, S.-U. Lim*, Y.-H. Won*, S.-S. An_, E.-Y. Lee_, S.-J. Moon_ and J.Kim_ *Department of Dermatology, Chonnam University Medical School, Hack-Dong 8, Gwangju 501-757, Korea, _Skin Research Institute, Amore Pacifi c Corporation R&D Center, Yongin-si, Gyeonggi-do 446-729, Korea and _Division of Dermatology, David-Geffen School of Medicine UCLA, 10833 Le Conte Ave, Los Angeles, CA 90095, USA Seong-Jin Kim, Department of Dermatology, Chonnam University Medical School, Hack-Dong 8, Gwangju 501- 757, Korea. Tel.: +82-62-220-6683 fax: +82-62-222- 4058 e-mail: seongkim@chonnam.ac.kr Sensitive skin is characterized by subjective symptoms that are hard to quantify. However, a neurobiological approach could improve our understanding of the nature of skin sensitivity. In this study, we measured the sensory perception of well-controlled electric currents on the skin that stimulated sensory nerve fi bres such as the myelinated A fi bre, A delta fi bre and unmyelinated c-fi bre. The sensory perception thresholds were obtained quantitatively from subjects with sensitive-prone skin and controls. Application of 0.075% capsaicin, known to stimulate the nociceptor c-fi bre, was topically applied then the sensory perception thresholds were measured to determine whether the exposure to nociceptive stimulation could affect the subsequent sensory perception. The results showed that the perception thresholds of skin sensitive-prone subjects were low for the c-fi bre measurements at 5 Hz electric current stimulation. Furthermore, a wide variation in sensory perception was noted in the skin sensitive-prone subjects after topical application of capsaicin. In conclusion, the abnormal sensory perception in individuals with sensitive skin appears to be related to neurological instability, where c-fi bre nociception plays a role. Thus, quantitative sensory perception threshold measurement was found to be a useful method for the identifi cation of skin sensitive-prone subjects. Cocoa polyphenols and their infl uence on parameters involved in ex vivo skin restructuring P. Gasser*, E. Lati*, L. Peno-Mazzarino*, D. Bouzoud*, L. Allegaert_and H. Bernaert_ *Laboratoire BIO-EC, 91165 Longjumeau, France and _Barry Callebaut, Aalstersestraat 122, 9280 Lebbeke, Belgium Laurent Peno-Mazzarino, Laboratoire BIO-EC, 1, Chemin de Saulxier, 91165 Longjumeau, France. Tel.: +33 169 41 42 21 fax: +33 169 41 61 65 e-mail: l.peno-mazzarino@ bio-ec.fr Polyphenols in general are compounds that are known to promote health and have a preventive effect against various chronic diseases. The infl uence of cocoa polyphenols on skin, however, has scarcely been studied from a histological point of view. The aim of this study is to assess the infl uence of cocoa polyphenols on several indicators of skin elasticity and skin tonus, namely, glycosaminoglycans and collagen I, III and IV. This was carried out by using a model of ex vivo human skin explants maintained in survival, on which a cocoa polyphenols extract was applied. After processing by standard histological techniques (fi xation, paraffi n embedding, sectioning, staining, immunostaining and microscopical observation), the infl uence of cocoa polyphenols on the evaluated parameters was quantifi ed by image

ABSTRACTS 53 analysis. The results obtained show that cocoa polyphenols exhibit a positive action on the parameters assessed, and the dose at which they improve the most parameters associated with skin tonus and elasticity was determined. Their activity was compared with a commercially available product, and the results obtained show that their effi cacy is equivalent. Moreover, an enhancing effect of cocoa butter on activity of cocoa polyphenol was highlighted. Now that the properties of cocoa polyphenols on ex vivo skin restructuring parameters have been assessed, the next step could include their evaluation in vivo. Properties of a new hydrotrope hydrophobic molecule and its potential applications E. Schnell*, D. Touraud*, R. Gick_and W. Kunz* *Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg and _CABB GmbH, Ludwig-Hermann-Strasse 100, D-86368 Gersthofen, Germany Werner Kunz, Institut für Physikalische und Theoretische Chemie, Universität Regenburg, D-93040 Regensburg, Germany. Tel.: +49 941/943 4044 fax: +49 941/943 4532 e-mail: Werner.kunz@chemie.uni-r.de In the present contribution, the properties of dipropylene glycol isobornyl ether (Pribelance_) are discussed, especially in the context of microemulsion and emulsion formulations. Pribelance_ is a new low-toxic anti-foaming hydrotrope with excellent co-surfactant properties that has some similarities with long-chain alcohols, but in contrast to them, it is liquid at room temperature. In combination with another, more hydrophilic cosurfactant, it allows signifi cant amounts of oil to be solubilized in water. Possible applications such as in cosmetics, as an anti-foaming agent or as additive to cooling lubricants are discussed. Further potential applications are plasticizers, fermentation systems, agrochemicals and waste-water treatments. Screening of Nepalese crude drugs traditionally used to treat hyperpigmentation: in vitro tyrosinase inhibition A. Adhikari*, H. P. Devkota*, A. Takano_, K. Masuda_, T. Nakane_, P. Basnet* and N. Skalko-Basnet* *The School of Pharmaceutical and Biomedical Sciences, Pokhara University, Pokhara, PO Box 427, Pokhara, Nepal, _Medicinal Plant Garden and _Department of Phytochemistry, Showa Pharmaceutical University, Machida, 194-8543, Tokyo, Japan A. Adhikari, The School of Pharmaceutical and Biomedical Sciences, Pokhara University, Pokhara, PO Box 427, Pokhara, Nepal. Tel.: +977 61 528 467 fax: +977 61 539 218 e-mail: adhikarianjana@gmail.com South-East Asian population is daily exposed to strong sunlight. As a result, the majority of population will have darker, ethnic skin. Moreover, many people suffer from dark spots, hyperpigmentation, which is considered to be a skin disorder and causes psychological disturbance. To treat dark spots, most of the population will still rely on traditionally used crude drugs, knowledge about which is transferred from generation to generation. Fifty-two crude drugs were selected based on the survey performed among local healers and beauticians of different ethnic origin. These crude drugs were screened for mushroom tyrosinase inhibitory activity, as tyrosinase inhibitors are becoming increasingly important as cosmetic and medicinal products, primarily to control hyperpigmentation. Among the tested crude drugs, methanolic extracts of Glycyrrhiza glabra, Morus alba, Syzygium aromaticum, Citrus aurantifolia, Cypreae moneta, Punica granatum and Citrus aurantium, at the fi nal concentration of 50 lg mL)1, showed mushroom tyrosinase inhibitory activity of 78.9%, 71.0%, 69.4%, 59.0%, 56.0%, 53.4% and 51.9%, respectively, with 91.4% inhibitory activity of kojic acid taken as positive control. To our knowledge, this is the fi rst report that extracts of Cypreae moneta shell and Syzygium aromaticum fl owering bud have tyrosinase inhibitory activity. These potent extracts were further evaluated at different concentration. The fi nal concentration of the extracts in reaction mixtures was 50, 25 and 5 lg mL)1 for the initial concentration of 1000, 500 and 100 lg mL)1, respectively. They showed concentration- dependant inhibition of mushroom tyrosinase. Those extracts expressing relatively weak tyrosinase inhibitory activity may act through different inhibition pathway which is not based on tyrosinase activity. Further evaluation of the most potent tyrosinase inhibitors in in vivo conditions would be recommended. Adaptation of the protocol for determining in vitro the sun protection factor of anti-solar sticks B. Choquenet, C. Couteau, E. Paparis and L. J. M. Coiffard Université de Nantes, Nantes Atlantique Universités, LPiC, MMS, EA2160, Faculty of Pharmacy, 1 rue G. Veil - BP 53508, Nantes F-44000, France