碩士 / 臺北醫學大學 / 生藥學研究所 / 96 / In this study, 105 strains of marine bacteria isolated from Taiwan were cultured for the screening of their antibacterial activities by disc agar diffusion method. Of these bacterial strains monitored, 2 strains exhibited antibacterial activities. Among them, bacterial strains M1B (Pseudomonas aeruginosa) and AW52 (Rhodobacteraceae) showed significant antibacterial activities toward Penicillin G-resistant Staphylococcus aureus. (ATCC 11631). Besides, all the marine bacterial extracts on vasorelaxing activities of SD rats induced by phenylephrine were also examined. Of these bacterial strains monitored, strains M1B (P. aeruginosa) and MO6 (B. firmus) exhibited vasorelaxing activities. Based on this findings, the 3 bacterial strains were mass cultured using PY broth. Then, the bioactive constituents were obtained by a series of chromatographic separation, and characterized by spectral analysis. Totally 15 compounds including 2 quinoline alkaloids, 2 phenazine alkaloids, 4 phenylamide derivates, 6 diketopiperazines and a 2-aminophenyl acetate were isolated and identified . Their structures were elucidated to be 2-n-heptylquinol-4-one (1), 2-aminophenyl acetate (2), cyclo-L-Pro-L-Phe (3), cyclo-L-Tyr-L-D-Pro (4), hydroxyphenazine (5), phenazine-1-carboxamide (6), N-(2’-Phenylethyl)isobutyramide (7), 2-Ethyl-N-(2’-phenethyl)butyramide (8), 2-Methyl-N-(2’-phenylethyl)butyramide (9), N-(2’-phenylethyl)isovaleramide (10), 2-heptyl-4-hydroxyquinoline-N-oxide (11), cyclo-L-Pro-L-Ile (12), cyclo-L-Pro-L-Val (13), cyclo-L-Pro-L-Leu (14), and cyclo-L-Pro-L-Met sulfoxide (15). Among them, cyclo-L-Pro-L-Met sulfoxide (15) was isolated for the first time from the natural source. The bioactivities of all the pure entities were further evaluated. The results of biological tests indicated that 1, 5, 6 and 11 exhibited strong antibacterial activity toward resistant S. aureus, with minimum inhibitory concentrations (MIC) of 64, 36, 36 and 24 ug/ml, respectively. Additionally, 1 and 11 showed significant cytotoxic activitives against NPC-tw01, HCT-116, Jurkat, and H661 cancer cell lines, with an IC50 values from 7.1 to 14.7 uM.
| Identifer | oai:union.ndltd.org:TW/096TMC05553004 |
| Date | January 2008 |
| Creators | Yi-Hung Lee, 李翊弘 |
| Contributors | 李宗徽 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 166 |
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