阿坝地区狼毒内生放线菌多样性及抗菌活性

通过可培养方法以四川省阿坝地区药用植物狼毒为研究对象,探究其内生放线菌多样性及抗菌活性,为开发新型生物活性物质提供依据.结果如下,1)多种因素决定了狼毒内生放线菌分离数量,其中土壤有机质与其相关系数为0.86,在0.05水平相关性显著.2)高氏一号培养基分离52株内生放线菌,占总数30.4%;植株不同部位分离内生放线菌结果为根部>茎部>叶部>花部.3)16S rDNA-RFLP将供试菌株分成11个遗传群,代表菌株系统发育分析表明,供试菌株以链霉菌属为主,其余菌株包括诺卡氏菌属,北里孢菌属,克里布所菌属.4)对代表菌株NRPS,PKS基因分析共获得4个PKS基因和2个NRPS基因;大部分代表菌株对3种病原真菌有抗菌活性,菌株SCAUEⅢD11-1效果最好.综上,狼毒内生放线菌分离结果受多因素影响,具有较丰富的多样性;功能基因筛选及抗菌活性结果揭示出阿坝地区狼毒内生放线菌具有潜在的运用价值.

Diversity and anti-microbial activity of endophytic actinomycetes isolated from Stell-era chamaejasme sampled in Aba,Sichuan

In order to develop new biologically active substances in medicinal plants,an isolation and culture method was employed to investigate the taxonomic diversity and anti-microbial activities of endophytic actino-mycetes isolated from Stellera chamaejasme sampled in Aba,Sichuan.It was found that the number of iso-lates was affected by many factors,especially organic matter content which was significantly positively correla-ted with the isolate number (P <0.05,r=0.86).Fifty two isolates were obtained on Gauze No.1 growth me-dium,accounting for 30.4% of total isolations.The numbers of isolates decreased in the following order:root, stem,leaf and flower.Analysis using 16S rDNA-RFLP divided these isolated strains into 11 clusters and fur-ther phylogenic analysis classified representative strains as genera Streptomyces ,Nocardia,Kitasatospora and Kribbella,respectively,with Streptomyces being predominant.PKS (4)and NRPS (2)genes were detected in the study and most of representative strains had antibiotic activity towards the pathogenic fungal strains, with SCAUEⅢD11-1 being most potent.It is concluded that behavior of isolates of endophytic actinomycetes from S .chamaejasme is affected by many factors with resulting diversity of expression.Functional genes and antibiotic activity indicated endophytic actinomycetes from S .chamaejasme sampled in Aba had potential me-dicinal value.