广西三种真红树植物可培养细菌多样性及其生物活性初筛

Diversity and biological activity of culturable bacteria in three true mangrove plants of Guangxi

为了挖掘真红树植物潜在细菌新物种和生物活性物质,丰富红树林微生物多样性,为新型活性产物开发提供菌株资源。该文从秋茄、木榄和红海榄三种广西来源的真红树植物及其生境中,按根、茎、叶、花、果实和泥土分成22份样品,选用8种不同培养基分离可培养细菌,通过16S rRNA基因序列鉴定,分析其多样性,采用纸片法筛选细菌发酵粗提物的抑菌活性,点植法测试其酶活性。结果表明:(1)共分离获得可培养细菌35株,隶属于23个科28个属,芽孢杆菌属占细菌总数的14.3%,为优势菌属,同时发现11株潜在的新细菌资源。(2)活性筛选获得4株细菌具有抑菌活性,16株细菌具有酶活性,芽孢杆菌属是酶活性优势菌属。综上所述,广西真红树植物可培养细菌多样性丰富,部分细菌具有抑菌活性和酶活性,在新型抗生素和酶应用方面具有一定的开发潜力。

This study aims to explore potential new bacterial species and bioactive substances in true mangrove plants,which can enrich the diversity of mangrove microorganisms and provide strain resources for the development of new active products.A total of 22 samples were collected from three true mangrove plants of Kandelia candel,Bruguiera gymnorrhiza,Rhizophora stylosa,and their habitats,in Guangxi coastal area.Then 22 samples were divided according to different parts such as roots,stems,leaves,flowers,fruits and soils.Eight different culture media were used to isolate culturable bacteria,and 16S rRNA gene sequences were used to identify bacteria and analyze diversity.For cultured bacteria,the antibacterial and enzyme activities of fermented crude extracts were screened with Kirby-Bauer method and spot planting method,respectively.The results were as follows:(1)Based on sequencing results of 16S rRNA gene,a total of 35 strains of culturable bacteria were isolated,belonging to 28 genera and 23 families.Bacillus accounted for 14.3%of the total bacteria,which was the dominant bacteria.Meanwhile,11 potential new bacterial species were found.(2)Four strains of bacteria showed antibacterial activities,16 strains had enzyme activities,and Bacillus was the dominant strain in enzyme activities.The above results show that Guangxi true mangrove plants are rich in bacterial diversity,and some bacteria show antibacterial activities and enzyme activities.The new bacterial species and active strains had certain development potential in the new antibiotics and enzymes application.