Modified Rancimat Method for Evaluation of Antioxidative Effect against Skin Lipids

摘要: Skin is a highly complicated tissue which possesses the largest surface area in body and serves as protective layer for internal organs. It designed to give both physical biochemical protection, equipped with large number of defense mechanisms. 1 However, skin very susceptible oxidative reaction, because there are rich contents lipids, proteins DNA cell, all sensitive oxidation process. 2 Lipid peroxidation could be induced from excessive exposure UV light, has been considered major factor aging processes. 3 In particular, squalene, main component polyunsaturated easily peroxidized. 4 The initial product peroxidized squalene-monohydroperoxide (Sq-OOH), produced at human by natural sun light. Recently, damages hairless mice topical application Sq-OOH 5 have reported. Repeated clear wrinkles. Thus, order prevent or retard process, prevention lipid chemical antioxidants desirable. To identify efficient cosmetic applications, convenient assay method suitable estimation necessary. Rancimat 6 can evaluate observing change electrical conductivity due formation volatile dicarboxylic acids. used food industry determine unsaturated fatty acid components. rancimat not suited research, composition oils source this different that lipid. 6c report, we demonstrate modified powerful tool screening peroxidation. We changed what close At first, tested antioxidative activities several extracts using general method. As shown Table 1, Korean medicinal plants presented induction time on retarding corn oil. Their were compared BHT positive control. Among three extracts, Scutellaria baicalensis Georgi (SBG) extract was found most activity. Portulaca oleracea L. (POL) appeared compound next activity Rheum coreanum Nakai (RCN) less active than other extracts. > SBG POL RCN. ranges Pf values too small (from 1.2 1.6). sensitivity enough primary establish system studies, prepared artificial it instead 7 consisted pork lard (33%), stearic (24%), lanolin (22%), squalene (12%) cholesterol (4%). This similar skin. According 2, results new previous data. Surprisingly, shows strongest among samples. Induction period 11.4 times longer control evaluation dramatically increased wide value 2.2 11.4). interesting observe between RCN ROL reversed. contrast data, more POL. These meaningful differences may changing research. search antioxidant applicable peroxidation, selected meso-dihydroguaiaretic (MDGA) 8 candidate. MDGA, naturally occurring polyphenol,