具有抑制肠道致病菌和黏附Caco-2细胞作用的益生性乳酸菌的筛选及鉴定

为了筛选具有肠道益生特性的乳酸菌,进一步开发益生菌资源,本文研究采用牛津杯、人工模拟胃肠液及体外黏附Caco-2细胞等方法,以鼠李糖乳杆菌GG(Lactobacillus rhamnosus GG,LGG)为对照菌株,对实验室保藏15株乳酸菌的益生特性进行筛选与评估。实验结果表明:15株乳酸菌对两株沙门氏菌都具有一定抑制效果,抑菌圈直径为10.95~22.06 mm;乳酸菌C174、D24、D599、C37、D512具有较好的耐酸耐胆盐能力,在人工胃液3 h内存活率达到60%以上,人工肠液4 h内存活率达到80%以上;在黏附试验中,C174对Caco-2细胞具有较强黏附能力,黏附数量为740 CFU/100细胞,略高于对照菌株鼠李糖乳杆菌(543 CFU/100细胞);通过对具有高黏附性的菌株C174进行生理生化和16S rRNA分子测序鉴定,结果表明菌株C174为植物乳杆菌(Lactobacillus plantarum),命名为Lactobacillus plantarum ZJ-174。Lactobacillus plantarum ZJ-174的抑菌能力强、能够耐酸耐胆盐,并具有很强的黏附能力,是一株潜在的益生菌,具有治疗或预防人和动物肠道疾病等应用价值。

Screening and Identification of Probiotic Lactobacillus Strains Inhibiting Intestinal Pathogens and Adhering to Caco-2 Cells

To screen Lactobacillus with intestinal probiotic characteristics and further develop probiotic resources,the probiotic characteristics of 15 Lactobacillus strains preserved in laboratory were screened and evaluated by Oxford cup,artificial gastrointestinal juice and adhesion to Caco-2 cells in vitro,using Lactobacillus rhamnosus as the control strain. The results showed that 15 Lactobacillus strains had certain inhibitory effect on both Salmonella strains,and the diameter of the inhibitory zone was 10.95~22.06 mm. Lactobacillus C174,D24,D599,C37 and D512 had good acid and bile salt tolerance,and the survival rate in artificial gastric juice was over 60% for 3 h and it was over 80% for 4 h in artificial intestinal juice. In the adhesion test,C174 had strong adhesion ability to Caco-2 cells. The number of adhesion was 740 CFU/100 cells,which was higher than that of control strain Lactobacillus rhamnosus GG(543 CFU/100 cells). The physiological and biochemical characteristics and 16S rRNA molecular sequencing identification of probiotic strain C174 with good adhesion capacity showed that the strain C174 was Lactobacillus plantarum,named Lactobacillus plantarum ZJ-174.Lactobacillus plantarum ZJ-174 was a potential probiotic with strong antimicrobial activity,acid and bile tolerance,and strong adhesion ability. It has application value in treating or preventing intestinal diseases of human and animals.