猪源益生枯草芽孢杆菌的分离鉴定及培养条件优化

摘要

采集健康仔猪肠道，从空肠黏膜分离到23株对大肠杆菌和金黄色葡萄球菌有拮抗作用的芽孢杆菌，复筛获得5株拮抗活性较高者；从中筛选出可耐受胆盐、人工胃液和肠液的菌株JN-16，分子生物学和部分生化试验鉴定结果表明：该菌为枯草芽孢杆菌。对菌株JN-16进行抑菌培养条件优化，结果表明，以葡萄糖为碳源、大豆蛋白胨为氮源、pH为6.5的培养基在33℃或37℃下，培养24 h时，发酵液的抑菌效果最强。该菌株可用作饲料添加剂，为微生态制剂的研发奠定了基础。%A total of 23 Bacillus strains antagonistic to Escherichia coli and Staphylococcus aureus were isolated from jejunal mucosa of healthy piglets,and 5 of them possessed higher antagonistic activity.The strain named JN-16 was isolat-ed and tolerant to bile salts,artificial intestinal juice and gastric juice.The results of molecular biology and biochemical ex-periments demonstrated that JN-16 was Bacillus subtilis.The results of antibacterial experiments showed that the antibacte-rial activity of broth was strongest,when the JN-16 was cultured at 33 ℃ or 37 ℃ for 24 h using glucose as carbon source,soy peptone as nitrogen source,pH=6.5.This strain could be used as feed additives,and laid foundation for devel-opment of probiotics.