一株抑菌型地衣芽孢杆菌的快速分离与鉴定及其对4株耐药致病菌的抑制作用

[目的]本文旨在分离具有良好抗菌活性的芽孢杆菌菌株作为抗生素替代品材料。[方法]通过热处理和抑菌板双重筛选对革兰氏阳性菌和阴性菌均具有抗菌活性的芽孢杆菌，并通过形态学、生理生化和分子生物学方法鉴定分离菌株。体外测定分离菌株发酵上清液对4株耐药致病菌的抑制作用。[结果]分离到6株对革兰氏阳性菌和阴性菌均具有抗菌活性的芽孢杆菌，其中分离菌株BB11的抑菌活性最强，对沙门氏菌C782和大肠杆菌K12D31的抑菌圈直径分别达15.34和6.26 mm。染色镜检BB11菌为带芽孢的革兰氏阳性菌，理化特性与芽孢杆菌相符。BB11菌的16S rRNA序列与地衣芽孢杆菌（Bacillus licheniformis）BCRC 15413序列的相似度在99%以上，gyrB基因序列与B. licheniformis BCRC 12826序列的相似度达到100%。BB11菌株的发酵上清液对具有多重耐药的致病性大肠杆菌K88、K99、987P和沙门氏菌C782均表现出较好的抑杀作用。[结论]分离到的地衣芽孢杆菌BB11具有用于开发多功能微生态制剂的潜能。
[Objectives] This paper aims to isolate Bacillus strains with antibacterial activity as antibiotics alternatives. [Methods] Bacillus strains with antimicrobial ability against both Gram-positive and Gram-negative bacteria were double screened by heat treatment and bacterial culture plates,and then identified by morphological characteristics,physiological and biochemical responses,and molecular methods. The antibacterial activity against four resistant pathogens was detected in vitro. [Results] Six Bacillus strains with antimicrobial effectiveness were isolated. The strain named BB11 showed the strongest antibacterial activity,and its inhibition zone diameters against Salmonella C782 and E.coli K12D31 were 15.34 mm and 6.26 mm,respectively. The strain BB11 was Gram-positive bacteria with spores by Gram and spore staining,and its physical and chemical properties were consistent with the Bacillus. The strain BB11 was identified as B. licheniformis with identity percentage of 99% compared with the reference strain(BCRC 15413) in 16S rRNA sequence and 100% compared with the reference strain(BCRC 12826) in gyrB sequence. The result showed good antibacterial ability of the supernatant of the strain BB11 against the multiple drug-resistant pathogenic E.coli K88,K99,987P and Salmonella C782. [Conclusions] Bacillus licheniformis BB11 has the potential for the development of multifunctional probiotics