摘要
目的对分离自地衣植物猫耳衣的一株内生细菌进行分子鉴定，分离鉴定其代谢产物，并对代谢产物进行抗菌活性测试。方法采用形态观察和16SrRNA基因序列同源性分析，在GenBank数据库中比对，并采用构建系统进化树的方法，对菌株进行分类学鉴定；采用硅胶柱色谱，凝胶柱色谱和高效液相色谱方法进行成分分离；根据理化性质和波谱数据对代谢产物进行结构鉴定；采用96孔板倍比稀释法进行抑菌活性测定。结果鉴定出供试菌株为一种甲基杆菌，从其大米发酵培养基中共分离得到6个化合物，鉴定为苯乙酸（1），对羟基苯甲酸（2），3-吲哚甲酸（3），吲唑（4），尿嘧啶（5），5-甲基尿嘧啶（6）。结论6种化合物均为首次从该菌中分离；体外抗大肠埃希菌和金黄色葡萄球菌实验表明，化合物1～6对两种供试菌株抑制活性（MIC值）均大于512μg／mL。
Objective To identify the endolichenic bacteria isolated from Leptogium sp., isolate its metabolism, and evaluate their antibacterial activity. Methods By the methods of morphology and evaluation of the gene sequence of 16S rRNA, sequence comparison in GenBank Database and construction of phylogenetic tree, the taxonomy status of the endolichenic bacteria can be firmed. Constitutes were isolated by gel column chromatography, Sephadex LH-20 and HPLC; Structures were illuminated. Double dilution method was adopted to evaluate antibactrial activity. Results The testing strain was identified to be Methylobacterium sp. Six compounds were isolated and purified from the fermentation of the endolichenic fungus. Their structures were elucidated to be phenylacetic acid （1）, 4-hydroxybenzoic acid （2）, 1H-indole-3-carboxylic acid （3）, 1H-indazole （4）, pyrimidine-2,4（1H,3H）-dione （5）, 5-methylpyrimidine-2,4（1H,3H）-dione （6）. Conclusion The six compounds were isolated from this fungus for the first time. Antibacterial bioassay showed that all six compounds exibit no inhibition on Escherichia coli and Staphylococcus aureus with MIC value beyond 512μg/mL.
出处
《中国抗生素杂志》
CAS
CSCD
北大核心
2016年第7期520-523,共4页
Chinese Journal of Antibiotics
关键词
地衣内生细菌
甲基杆菌
抗菌活性
Endolichenic bacteria
Methylobacterium sp.
Antibacterial activity
