Studies On The Chemical Constituents And Bioactivities In Stems And Leaves Of Lagerstroemia Indica L.

The species Lagerstroemia indica L. was belonging to genus Lagerstroemia of Lythraceae, the Chinese name was Ziwei, simultaneously, the other name was used in China, including Zijin flower, Yangyang flower, Wenzi flower, Xiyangshuiyanmei,Bairihong and so on. It mainly distributed in Guangxi, Guangdong, Fujian and Taiwan. The taste was bitter, astringent and cold, with heat-clearing and detoxifying,eliminating dampness and stopping bleeding. So it has been used for the treatment of dysentery, carbuncle swollen poison, eczema, trauma and bleeding etc. This thesis is focused on the biological activity screening of its primary extract and the chemical constituents of active extract in L. indica L. The compounds were isolated and purified with silica gel, Sephadex LH-20 column chromatography, TLC and HPLC,and their structures were identified on the basis of chemical and spectral data. The mainly results and conclusions were summarized as follows:1. Fifteen compounds were isolated from the ethanol extract in stems and leaves of L.indica and identified as follows: 1,2-bis(3-hydroxy-4-methoxyphenyl)-3-oxopropyl acetate(1), 4-(3-hydroxy-5-(4-hydroxyphenyl)pentyl)-2-methoxyphenol(2), 4-(8-methoxy-1, 3a, 4, 5a, 6, 7-hexahydrocyclopenta [c]benzofuran-4-yl)phenol(3), morusin(4), morusinol(5), neocyclomorusin(6),matairesinol(7), yunnanensin A(8), quercetin(9), quercetin-3-O-?-D-glucopyranoside(10), 4’,7-dihydroxyflavone(11), kaempferol(12),p-methoxycinna-maldehyde(13), 5,5’-dibutoxy-2,2’-bifu-ran(14), loliolide(15). Among them, compound 1, 2, 3 are new compounds, compound 3 has a new carbon skeleton, compounds 4, 5, 6 and 8 are isolated from this species for the first time.2. The preliminary glucose-decreasing activity screening of 95 % ethanol extract of stems and leaves of L. Indica was carried out. The results showed that this extract had inhibitory activities on ?-glucosidase and ?-amylase, and their ethyl acetate fraction had potent inhibitory activities on ?-glucosidase, and the inhibition rate is 73.60 %;the chloroform fraction had potent inhibitory activities on ?-amylase, and the inhibition rate is 61.46 %, the N-butanol alcohol fraction had potent inhibitory activities on ?-glucosidase, the water fraction had potent inhibitory activities on ?-amylase. This suggests that the inhibitory activities on carbohydrate degrading enzyme are present at all fractions of 95 % ethanol extract of L. Indica but their types and effectiveness are different.3. The anti-inflammatory activity screening showed that the ethyl acetate fraction have a weak anti-inflammatory activity.4. The cytotoxic acitivity screening showed that chloroform fraction had inhibitory activities on Hep G2, ethyl acetate fraction had inhibitory activities on Hep G2 and A2780.