海洋来源真菌Aspergillus sp.SCSIO 81-F2抗菌活性次级代谢产物的研究

采用抑菌活性追踪的方法,利用硅胶柱色谱和半制备反相高效液相色谱法对一株南海海洋来源真菌SCSIO 81-F2的发酵产物进行分离,纯化获得3个单体化合物,通过理化性质、MS、NMR及X-单晶衍射分析,分别鉴定为xanthocillin X dimethylether(1)、xanthocillin X monomethylether(2)、6',8'-dimethoxy xanthocillin X dimethylether(3)。经18S r DNA序列分析并构建系统发育进化树,鉴定该菌株为曲霉属真菌Aspergillus sp.SCSIO 81-F2。海洋曲霉菌Aspergillus sp.SCSIO 81-F2是一个能产生具有抗菌活性xanthocillin类抗生素的新来源。

Chemical profile of the secondary metabolites produced by a deep-sea sediment-derived fungus Penicillium commune SD-118

Bioassay-guided fractionation of the crude extract from Penicillium commune SD-118, a fungus obtained from a deep-sea sediment sample, resulted in the isolation of a known antibacterial compound, xanthocillin X (1), and 14 other known compounds comprising three steroids (2-4), two ceramides (5 and 6), six aromatic compounds (7-12), and three alkaloids (13-15). Xanthocillin X (1) was isolated for the first time from a marine fungus. In the bioassay, xanthocillin X (1) displayed remarkable antimicrobial activity against Staphylococcus aureus and Escherichia coli, and significant cytotoxicity against MCF-7, HepG2, H460, Hela, Du145, and MDA-MB-231 cell lines. Meleagrin (15) exhibited cytotoxicity against HepG2, Hela, Du145, and MDA-MB-231 cell lines. This is the first report of the cytotoxicity of xanthocillin X (1).

二甲基黄青霉素抑制肿瘤细胞增殖的机制

目的:研究二甲基黄青霉素抑制人肿瘤细胞增殖的作用机制。方法:用MTT法检测细胞增殖的抑制作用,流式细胞仪检测细胞周期分布以及细胞内活性氧自由基的水平,Western blotting检测凋亡相关蛋白的表达。结果:二甲基黄青霉素明显地抑制人肝癌HepG2细胞、人乳腺癌MCF-7细胞和人口腔上皮癌KB细胞的增殖,其IC50值分别为0.18,0.38,0.44μg.mL-1。进一步研究发现:二甲基黄青霉素使细胞阻滞在G2/M期,增加细胞内活性氧自由基水平,激活细胞凋亡通路。结论:二甲基黄青霉素具有明显的抑制肿瘤细胞增殖的作用,其机制与诱导细胞凋亡有关。