海芒果可培养细菌的分离鉴定及其抑制海洋鱼类致病菌活性研究

【目的】研究红树植物海芒果Cerbera manghas L.及其根际土壤可培养细菌多样性及其代谢产物抑制鱼类致病菌的生物活性。【方法】采用纯培养法分离并基于16SrRNA基因序列的系统发育分析法对分离得到的细菌进行多样性研究,采用滤纸片法研究其抑制海洋鱼类致病菌的生物活性。【结果】从海芒果及其根际土壤中共分离得到15株可培养细菌,采用16SrRNA基因序列的系统发育分析后发现,这些菌分属于2个大的细菌发育类群:厚壁菌门(Firmicutes,占比为53%)和放线菌门(Actinobacteria,占比为47%),其中4株为芽孢杆菌属,6株为链霉菌属。活性研究发现,所有测试菌株对3种海洋鱼类致病弧菌均有一定的抑制作用,其中VT86(Kitasatospora paranensis),V139-2(Streptomyces luteireticuli),V140-2(Streptomyces jiujiangensis),VT19(Streptomyces orinoci),VT113(Streptomyces niveiscabiei)这5株菌的抑菌效果较好,以VT86(K.paranensis)抑菌活性最好。【结论】红树植物海芒果及其根际土壤中的细菌丰富多样,部分细菌具有抑制海洋鱼类致病菌生长的生物活性,具有开发成新型抑制鱼类致病菌药物的潜力。

Identification and Inhibition Activity Inhibit Fish Pathogens of Cultivated Bacteria Isolated from Cerbera manghas

[Objective] To study the bioactivity of Cerbera manghas and its rhizosphere soil to cultivate bacterial diversity and its metabolites to inhibit fish pathogens. [Methods] The diversity of isolated bacteria was studied by the method of pure culture and the phylogenetic analysis based on 16S rRNA gene sequence using the filter paper method,the isolated bacteria were tested to inhibit the activity of marine fish pathogenic bacteria.[Results] We isolated 15 bacterial strains from Cerbera manghas and its rhizosphere soil through conventional culture dependent method,identified the strains according to morphological observation,physiological,biochemical characteristics,and the homologous analysis of 16S rRNA sequences of nucleotides. Results showed that these strains belonged to two major bacterial development groups:Firmicutes (53%) and Actinobacteria (47%),of which 4 were Bacillus sp.,6 were Streptomyces.Activity showed that the VT86 had the best antibacterial activity,which might have potential value for developing new inhibition of sea fish pathogens drugs.[Conclusion] Cerbera manghas and its rhizosphere soil were rich in bacteria resources,and biological activity of those strains could improve the prevention and treatment of sea fish diseases.