Screening of new antioxidants form oriental medicines resulted in the isolation of a new antioxidative compound and eight known compounds from the stem bark of Kalopanax pictus. On the basis of various spectrosopic studies, the structure of the new compound was determined to be 4-rhamnose-3,5-dimethoxybenzoic acid methly ester. Other known compounds were identified as ferulic acid, 4,5,6,-trihydroxyflavanone, 2', 4',4' -trihydroxychalcone, caffeic acid, coniferyl alcohol, syringin, 1,3-di-O-caffeoylquinic acid. These compounds showed lipid peroxidation inhibitory acitivity in rat liver microsomes and free radical scavenging acitivity.

Fifteen varieties of Oryza sativa mainly includig those of Korean native rice were exactly cutted into three layers such as L1 layer (the outer part of 90% from rice center), L2 layer(the part of 81 ~ 91% from the rice center) and L3 layer(the inner part of 80% from the rice center) and ferulic acid derivatives, which play an important role of antioxidative action, were quantitiavely analyzed by UV absorption spectrometric method at fixed 314nm. From this experiment, it was found that the more it enters from the surface into the rice center, the more those secondary metabolites contents were highly reduced. The varieties showing contents more than 20 mg/g were as follows: Hwasunchalbyeo(25.8mg/g), Jojeongdo(24.1mg/g), Suwon425(21.2mg/g), Daigolbyeo(20.6mg/g) and Nonglimna 1(20.2mg/g) by this order. Estimation onthe anthocyanin contents of both Suwon 425 and Sanghehanghyeolna revealed that its total. contents were very exactly close each other. However, it was charateristically differentiated in the contents of L2 layer with respect to showing a considerably higher content of Suwon 425 than of Sanghaehanghyeolna. Conclusively, the selected Suwon 425 variety, which is coloured and flavour volatile one, showed relatively higher contents of anthocyanin, ferulic acid derivatives in the L2 layer as well as L1 layer when compared with Sanghaehangyeolna and even other varieties. This fact suggested that Suwon 425 could be a promising candidate for the development of health rice food.

예로구터 그 수액이 건강보조식품으로 사용되어온 고로쇠나무의 줄기를 대상으로 항산화 활성을 가지는 성분을 찾기위하여 실험에 착수하였으며, 그 MeOH추출물의 ETOAc분획을 대상으로 Column chromatography를 실시하여 scopoletin, isoscopoletin, (-) -epicatechin등 3종의 화합물을 분리하고 항산화 활성을 측정하였다. 이중 scopoletin과 isoscopoletin은 BHA나 α-tocopherol보다 활성이 약하였으나 (RC50 : 120, 110 mug), (-)-epicatechin의 항산화활성 (RC50 : 7.5 mug)은 BHA나 α-tocopherol보다 뚜렷하게 높았다.

Changes in antioxidative substance levels in eleven different cultivars of persimmon leaves during growth were investigated. In general, the contents of soluble phenols, L-ascorbic acid and flavonoids in astringent persimmon leaves(APL) were higher than those of nonastringent persimmon leaves(NAPL). The soluble phenol contents in APL and NAPL showed a tendency to decrease throughout leaf growth. L-ascorbic acid content in APL decreased rapidly during growth, whereas its content in NAPL reached its highest value at the late of July, and then decreased rapidly. Major flavonoids in APL and NAPL were quercetin and Kaempferol which were present in conjugate forms. Before acid hydrolysis, the contents of kaempferol and quercetin in APL and NAPL remained at a relatively constant level until the late of July, and then decreased slightly. After acid hydrolysis, kaempferol contents in APL and NAPL varied significantly by cultivar and growth stage, while quercetin contents decreased slowly until the late of July, and then increased drastically, reached a maximum at the early of August, afterward continuously decreased. These results suggest that APL harvested at the early of June may be useful as potential sources of natural antioxidants.

Antioxidants of sesame have been reported to cure and prevent various diseases by means of diverse physiological activities, prevention of acidification in organisms, prevention of acidification and decay of lipids, cholesterol depression, preventive effects on chemical breast cancer, skin beauty and senescence inhibition, and so on. Recognizing their significance to health and disease prevention, researchers in Japan and America have given so much importance to study antioxidants in the last decade. In addition, they are actively pursuing studies on production, processing for food use and development of new varieties that have high antioxidant content. Recently, researchers in Korea have shown the same interest and have conducted similar studies, however, the importance of the following basic issues must be recognized to guide in future activites : First, improvement of sesame quality must be done to raise the contents of not only the fat and fatty acid but also sesamin, sesamolin and sesaminol glucoside. For the use of these components it is necessary to study the gentic pattern and individual selections developed from minimum sample size and fast lipid analysis techniques. Second, sesaminol of sesame has a remarkable function in preventing acidification and so sesame can be utilized as a food that prevents or delays aging caused by automatic acidification of fat. Therefore, for maximum medicinal benefit from sesame oil there is a need to develop food materials having new medicinal functions. Third, the sesamin and sesamolin content of sesame germplasms collected in Korea showed lower ranges of 0.04~~0.68 percent and 0.08~~0.68 percent respectively, while Japanese germ-plasm showed 1.9 percent maximum content of seasmin. Thus, germplasm collection and analysis of worldwide genetic resources are urgently needed.