关键词: 黄精, 内生菌, 发酵产物, 抑菌活性, 菌种鉴定

Abstract: Endophytes which live within the tissues of living plants can produce a wide variety of biological activity as host.Thus they become new resources for novel antimicrobial compounds screening.In this study,we isolated 11 endophytes from the healthy root of the wild Polygonatum cyrtonema of Huangshan area based on the tissue culturing.All these strains were used for fermentation by different mediums,and the fermented metabolites were then extracted with ethyl acetate to study the antibacterial activity with the scrip diffusion method.We finally screened an endophytic bacterium HJ-1 which generates stable metabolites that have significant antibacterial activity against Pseudomonas aeruginosa, Salmonella typhi and Bacillus thuringiensis，with the Minimum Inhibitory Concentration(MIC)values of 0.06-0.10 mg/mL and was identified the Bacillus spp.by morphology characteristics analysis and 16S rRNA sequence.It was the first reported that can produce antibacterial activity metabolites of Bacillus spp.from P.cyrtonema.This study provided a new insight into the development of endophytes resources from P.cyrtonema and screening new antibacterial compounds from its metabolites.

Key words: Polygonatum cyrtonema, endophytes, metabolites, antibacterial activity, identification