一株植物乳杆菌的分离、鉴定及其特性研究

Isolating,identification and characteristic research of a Lactobacillus plantarum

试验旨在寻找抗性菌,以替代部分抗生素,并研究其特性。用大肠杆菌K88、金黄色葡萄球菌和鼠伤寒沙门氏菌为指示菌,采用凝胶打孔法从猪肠道中筛选出一株对3种病原菌均具有拮抗作用的菌株,利用菌落形态、革兰氏染色、16S r DNA序列鉴定来鉴定菌株,并测定其生长曲线和产酸能力。结果显示,试验筛选到1株对大肠杆菌K88、金黄色葡萄球菌和鼠伤寒沙门氏菌均具有较强抑制作用的菌,经鉴定为植物乳杆菌(Lactobacillus plantarum),并命名为325。此分离菌为革兰氏阳性菌,单生或成对生长。按0.1%接种量接种时,培养至18 h时候产酸能力最高,此菌在抑菌方面具有良好的开发应用前景。

The experiment was to find a new antimicrobial bacterium and analyze the character to replace part of antibiotics.E.coli K88,Staphylococcus aureus and Salmonella typhimurium were used as the indicator bacteria,and a strain was isolated from pig cecum with resistance to the three pathogenic bacteria by gel punching.The strain was determined by colonial morphology,gram staining and 16 S rDNA sequence analysis,and then the growth curve and acid producing power were determined.The results showed that a strain named 325 was isolated and identified as Lactobacillus plantarum,which showed a better antimicrobial activity against E.coli K88,Staphylococcus aureus and Salmonella typhimurium.It was gram-positive,heterotrophic,single-birth or in pairs of growth.The acid producing power reached the max when the inoculate was 0.1%.In conclusion,Lactobacillus plantarum 325 had better probiotic character and more potential application prospects in production.