HAIR BLEACHING AND WAVING 175 (7) (8) (9) (lO) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) N. C. Wilson, The scientific aspects of bleaching, II. Wool, Textile J. Australia, 15, 496-498 (1941). G. Laxer and C. S. Whewell, The measurement of damage produced by treatment of wool with solutions of hydrogen peroxide, J. Soc. Dyers Color, 68, 256-257 (1952). H. Zahn, Chemische Ver•inderungen von Wolle beim Waschen, D•impfen und Bleichen, Textil- Rundschau, 19, 573-584 (1964). K. Ziegler, Neue Ergebnisse fiber das Bleichen von Wolle, Textil Praxis, 17, 376-380 (1962). C. R. Robbins, in: Chemical and Physical Behavior of Human Hair (van Nostrand Reinhold Company, New York, 1979), pp 69-71. W. E. Savige and J. A. MacLaren, "Oxidation of Disulfides, With Special References to Cystine," in: The Chemistry of Organic Sulfur Compounds, N. Kharasch Ed. (Pergamon Press, Oxford, 1966), Vol. 2, pp 367-4O2. J. F6hles, U. Schumacher-Hamedat, and H. Zahn, Methode einer differenzierten Cysteins•iurebes- timmung in sauren Totalhydrolysaten, International Wool Textile Organization (IWTO) Report No. 12, Copenhagen Meeting (1983). U. Schumacher-Hamedat, Modellstudien zur Entstehung yon part ell oxidierten Cystinderivaten be oxidativer Veredlung von Wolle, Thesis, Rheinisch-Westf•ilische Technische Hochschule, Aachen (1985). B. J. Sweetman, J. Eager, J. A. MacLaren, and W. E. Savige, A study of partial oxidation of the disulphide groups in wool, Proc. Int. Wool Text. Res. Conf. Paris, 1965, II, 85-97. J. Nachtigal and C. Robbins, Intermediate oxidation products of cystine in oxidized hair, Text. Res. J., 40, 454-457 (1970). U. Schumacher-Hamedat, to be published. R. C. Marshall and J. M. Gillespie, Comparison of samples of human hair by two dimensional dec- trophoresis, J. Forensic Sci. Soc., 22, 377-385 (1982). M. Witrig, I. Bindewald, R. C. Marshall, M. Stein, and H. Zahn, Two dimensional keratin patterns of single human hair fibres, Proc. 8th Austr. Intern. Forensic Sci. Symp., Perth Western Australia (1983). J. M. Gillespie and R. C. Marshall, "The Proteins of Normal and Aberrant Hair Keratins," in: Hair Research, C. E. Orfanos, W. Montagna, and G. St6ttgen, Eds. (Springer Verlag, Berlin, Heidelberg, New York, 1981), pp 76-83. J. G. Gumprecht, K. Patel, and R. P. Bono, Effectiveness of reduction and oxidation in acid and alkaline permanent waving, J. Soc. Cosmet. Chem. 28, 717-732 (1977). A. StrfilBmann, Deutsches Wollforschungsinstitut, Internal Project Report (1983). H. Zahn, T. Gerthsen, and M. L. Kehren, Anwendung schwefelchemischer Analysenmethoden auf dauergewelltes Haar, J. Soc. Cosmet. Chem., 14, 529-543 (1963). J. Chao, E. Newsom, and I. Wainwrite, Comparison of the effects of some reactive chemicals on the proteins of whole hair, cuticle and cortex, J. Soc. Cosmet. Chem., 30, 401-413 (1979). I. Bindewald, R. Greven, R. C. Marshall, M. Stein, G. Stephan , M. Witrig, and H. Zahn, Deutsches Wollforschungsinstitut, Internal Report for Bundeskriminalamt (1984).

j. Soc. Cosmet. Chem., 37, 177-189 (May/June 1986) Physicochemical properties and applications of and I-glycyrrhizins, natural surface active agents in licorice root extract MITSUO KONDO, HIROMI MINAMINO, GENICHIRO OKUYAMA, KEIICHI HONDA, HISANAO NAGASAWA, and YASUHISA OTANI, Cosmetics Laboratory, Kanebo, Ltd., 5-3-28 Kotobuki-cho, Odawara 250, Japan. Received August 17, 1983. Presented at the 12th IFSCC Congress, Paris, September 1982. Synopsis Physicochemical properties of [3-glycyrrhizin ([3-G, a triterpenoid saponin) and ot-glycyrrhizin (or-G, a stereoisomer of [3-G, newly developed as part of this study) were examined for cosmetic applications. Both or- and [3-G exhibited similar considerable interfacial activity. However, the aqueous solution of [3-G formed an extremely rigid gel in acidic media, whereas ot-G showed no sign of gelation. [3-G can emulsify various oily materials over a wide range of required HLB values, while ot-G has solubilizing ability for several perfume materials. A series of experiments was carried out to obtain some information on the solubilizing, emulsifying, and gelling mechanisms of or- and [3-G using •3C-NMR and scanning electron microscopy with various deriva- tives of Gs. The results suggested that the [3-G molecule which was found to be cyclically constructed constitutes the micelies which in turn orient anisotropically to form a rigid gel and to stabilize the emulsion. INTRODUCTION •3-glycyrrhizin (•3-G), a triterpenoid saponin present in licorice root extract, has been widely utilized in cosmetics owing to its excellent anti-inflammatory action (1). In addition to such characteristics, this compound was found to display unique physico- chemical behavior, particularly surface activity (2-4) and gel formation (5), even in dilute aqueous media. An isomer, (x-glycyrrhizin ((x-G, a new compound), was prepared to compare physical properties of the two isomers. The present paper deals with the surface activity, solubi- lizing and emulsifying mechanisms, and application to cosmetics of both Gs. Also, the mechanism of gelation by •3-G is discussed. EXPERIMENTAL MATERIALS (x- and [3-glycyrrhizins. (x-G was prepared by base-catalyzed isomerization of [3-G ac- 177