茅尾海红树根际土壤可培养细菌多样性及抑菌活性研究

为挖掘茅尾海红树植物根际土壤可培养细菌资源,研究其抑菌活性,该文使用培养基对茅尾海5种红树植物(红海榄、黄槿、无瓣海桑、桐花树、阔苞菊)的7份根际土壤进行富集培养,选用6种不同分离培养基对富集样品进行可培养细菌的分离纯化,基于菌株16S rRNA基因序列信息进行物种多样性分析,并采用纸片法筛选具有抑制表皮葡萄球菌、耐甲氧西林金黄色葡萄球菌、铜绿假单胞菌活性的菌株。结果表明:(1)从7份红树植物根际土壤样品中分离到120种可培养细菌,隶属于35科47属,其中链霉菌属(Streptomyces sp.)占菌种总数的 14.2%,同时发现5种潜在新菌株。(2)通过抑菌活性初筛,发现9种细菌的发酵粗提物对至少一种致病菌具有抑菌活性。综上表明,茅尾海红树植物根际土壤可培养细菌多样性丰富,并且部分菌株具有抑制人类致病菌活性。该研究结果为新型抗生素的开发与利用提供了菌种资源。

Research of antibacterial activity and culturable bacteria isolate from mangrove rhizosphere soil in Maowei Sea

In order to find culturable bacteria resources and antibacterial activity strain in the rhizosphere soil of mangrove plants from the Maowei Sea, the rhizosphere soil of five mangrove plants(Rhizophora stylosa, Talipariti tiliaceum, Sonneratia apetala, Aegiceras corniculatum, and Pluchea indica)was cultured by enrichment media and then isolated the culturable bacteria. The culturable bacteria were purified by six different isolation media. The diversity of culturable bacteria was analyzed by the 16S rRNA gene sequence information. Antimicrobial activities(Staphylococcus epidermidis, methicillin-resistant S. aureus, and Pseudomonas aeruginosa)of the culturable bacteria were analyzed by disk diffusion method. The results were as follows:(1)A total of 120 strains were isolated from seven rhizosphere soil samples of mangrove plants which could be classified into 35 families and 47 genera, among which five potential new species were obtained. The dominant genus was Streptomyces sp.(14.2%).(2)It was found that the crude extracts of nine strains had antibacterial activity against at least one pathogen. The results indicate that there are abundant culturable bacteria and potential new antibiotics resources in the mangrove rhizosphere soils from the Maowei Sea.