Chemical Composition Of Antioxidant Activity Tracking Flowers Anise Fruit

Medicinal plants used by ethnical people in rural area in China are important part of Chinese traditional medicine. In order to utilize the biological components in the Chinese traditional medicinal plants deeply and effectively, Illicium micranthum Dunn, were collected in Yunnan province and studied, according to the results of antioxidant activity screening tests.Illicium micranthum Dunn, shrubs or trees, distributed in the southwest region of China. Due to its toxicity, the twigs and leaves and fruits of the plant were traditionally used by the locals as pesticide. In the research, the antioxidant activity of the methanol extracts of fruits and twigs/leaves were tested by DPPH-spectrophotometric method. As a result, the methanol extract of fruits were chosen to be studied deeply. In the further DPPH-spectrophotometric test, ethyl acetate layer of methanol extract of fruits showed better antioxidant activity than other extracts, and was purified by silica gel column chromatography (Silica gel CC), Sephadex LH-20column chromatography (Sephadex LH-20CC), and preparing thin-layer chromatography (PTLC) repeatedly.14compounds were isolated finally from the ethyl acetate layer. Moreover, petrol ether layer of methanol extract of fruits was also studied, according to the literature, and14compounds were also isolated. The structures of all the28 compounds were elucidated by UV, IR, EI-MS,’H-NMR,13C-NMR and2D-NMR (’H-’H COSY, HMQC, HMBC). The compounds includes an ester of cinnamic acid and monoterpene:Pressafonin A(19); ten sesquiterpene compounds:Gynurenol(1),/?-elemol(2), epi-carrisone(3), β-eudesmol(4),6-hydroxy-eudesm-4(14)-ene(5), cryptomeridiol(6), a-photosantolol B diastereoisomer(1)(15), a-photosantolol B diastereoisomer(2)(16), a-photosantolol A(17),11-hydroxy-isocampheren-9-ene(18); five monoterpenes:(-)-isopulego(7),2-isopropenyl-5-methyl-cyclohexanol(8),4-isopropenyl-1-methyl-cyclohexanol(9),1R,2R,4R-three hydroxyl-menthane, thymol(20); and seven fatty acids derivatives: palmitic acid(12), stearic acid(13), eicosanol(22), octadecane acid(23), octacosanol(24), linoleic acid monoglyceride(25), glyceryl trioleate(26); and five other compounds:β-daucosterol(11), methoxybenzoic acid(14), β-sitosterol(21), benzoic acid(27), and trans-cinnamic acid(28). All the above compounds were isolated from Illicium micranthum Dunn’s fruits for the first time except for thymol,β-daucosterol and β-sitosterol. Furthermore, compoound (19) was reported from Genus Illicium for the first time.The research in this thesis provide not only primary data for the discovery of lead compounds from plant, but also fundamental data for the scientific development and utilization of medicinal plant resources in ethnical rural area of China.