抑菌性芽孢杆菌的筛选及特性研究

Screening and characterization of bacteriostatic Bacillus

试验旨在从自然环境中筛选出具有抑菌效果的有益菌株,对其生长特性进行初步研究。试验以大肠杆菌为指示菌对12株芽孢杆菌进行初筛,筛选出6株具有抑菌活性的芽孢杆菌并对其进行鉴定。再以大肠杆菌和金黄色葡萄球菌做指示菌,对芽孢杆菌抗菌肽提取物进行抑菌性筛选,并对筛选出的菌株进行溶血性比较、药物敏感性测定及生长特性研究。结果显示,从实验室分离筛选出具有较强抑菌活性的菌株为芽孢杆菌G02和J12,经鉴定为暹罗芽孢杆菌(Bacillus siamensis);筛选出两株芽孢杆菌的提取物均具有分泌表面活性的能力,且分泌表面活性的能力相当;两株芽孢杆菌对16种药物的敏感性均在中敏以上;两菌株在6 h进入生长对数期,pH值维持在5~8之间,抑菌性在22 h达到高峰。研究表明,芽孢杆菌具有产生多种活性肽的能力,对常见病原菌具有一定的抑制作用,是一种潜在的传统抗生素替代品。

The purpose of the experiment was to screen beneficial strains with antibacterial effects from the natural environment and study their growth characteristics.In the experiment,12 strains of Bacillus were screened with E.coli as indicator bacteria,and six strains of Bacillus with antibacterial activity were screened and identified.Then,Escherichia coli and Staphylococcus aureus were used as indicator bacteria to screen the antibacterial peptide extracts of Bacillus,and hemolytic comparison,drug sensitivity determination,and growth characteristics of the screened strains were studied.The results showed that Bacillus G02 and J12,which had strong antibacterial activity,were identified as Bacillus siamensis.The extracts of two strains of Bacillus had the ability of secreting surface activity,and the ability of secreting surface activity was equal.The sensitivity of two strains of Bacillus to 16 drugs was above medium sensitivity.The extracts of two strains of Bacillus had the ability of secreting surface activity,and the ability of secreting surface activity was equal.The sensitivity of two strains of Bacillus to 16 drugs was above medium sensitivity.The two strains entered the logarithmic growth phase at 6 h,the pH value was maintained between 5 and 8,and the antimicrobial activity reached its peak at 22 h.Studies have shown that Bacillus has the ability to produce a variety of active peptides,and has a certain inhibitory effect on common pathogenic bacteria,which is a potential substitute for traditional antibiotics.