中华剑角蝗肠道共生真菌的分离鉴定及抑菌活性筛选

Isolation,Identification and Antibacterial Activity of Intestinal Symbiotic Fungi from Acrida Cinerea

为了解中华剑角蝗肠道共生真菌的种类,并通过共生真菌次生代谢产物抑菌活性筛选,为蝗虫共生真菌的次生代谢产物开发利用提供参考.将采自湖北神农架的中华剑角蝗通过表面消毒后对其肠道共生菌分离纯化,运用rDNA-ITS序列分析进行鉴定,NJ法构建系统发育树分析其亲缘关系.以魔芋软腐菌、水稻白叶枯菌和猕猴桃溃疡菌为测试菌株,用滤纸片法对共生真菌的发酵液进行了抗菌活性筛选.结果显示,从中华剑角蝗的肠道中分离得到18株共生真菌,分属6科8属,其中青霉菌属和镰刀菌属是优势菌群,分别占总分离株的33.33%和27.78%;系统发育分析显示,18株共生真菌具有较丰富的种类多样性;抗菌实验结果表明,18株共生真菌有4株菌的代谢产物至少对1种测试病原菌有抑菌活性,占分离株的22.22%,其中有2株菌的次生代谢产物对魔芋软腐菌有较强的抑制作用.

This study is to know the variety of the Acrida cinerea intestinal symbiotic fungi,detect the antibacterial activity of their secondary metabolites and provide a reference for the development and utilization of locust symbiotic fungi.Here,we collect some A.cinerea from Shennongjia,plated on agar media after surface sterilized conducive for fungal growth,obtain pure cultures,and then employ the method of internal transcribed spacer （ITS） sequencing for identification of fungi.The antimicrobial activity of symbiotic fungi fermentatin broth against three microorganisms （Xanthomonas campestris pv.Oryzae,Erwinia carotovora subsp.Carotovora and Pseudomnas syringae pv.Actinidae） are investigated by using paper disc diffusion method.In total,18 fungal strains are isolated from A.cinerea＇s intestinal and identified belong to six species and eight genera.Penicillium sp.and Fusarium sp.are the dominant strains,representing 33.33% and 27.78 % of the total isolated colonies respectively.Our results indicate a greater diversity of the intestinal symbiotic fungi.There are 4 strains having antimicrobial activity against at least one of the tested bacteria,accounting for 22.22 % of isolates.And 2 strains have remarkable antimicrobial activity to Erwinia carotovora subsp.Carotovora.