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【目的】将分离自猪肠道粘膜、食糜和粪便的乳酸菌,通过产乳酸能力、生长性能、耐酸和耐胆盐性能及抑菌能力评价,筛选适应养猪生产的潜在益生特性的菌株。【方法】共分离获得155株乳酸菌纯菌株,从中筛选出4株产酸能力较强的乳酸菌,结合生理生化试验及细菌16S rRNA测序鉴定其种属,评价候选乳酸菌的生长情况、耐酸、耐胆盐及抑菌特性。【结果】综合变色时间(8 h)、pH值(<3.9)和乳酸含量(>100 mmol/L),筛选出4株(L45、L47、L63和L79)候选菌株,经鉴定依次为罗伊氏乳杆菌、植物乳杆菌、约氏乳杆菌和粪肠球菌。该4株乳酸菌均可在体外快速生长;L47和L79能够耐受pH 2.5的酸性环境,L47能够耐受0.5%胆盐环境;各乳酸菌上清液与指示菌共培养,发现对E coli K88和沙门氏菌均产生了抑制作用,其中L47上清液对指示菌的抑制作用较强。【结论】L47具有较好的产酸性能与生长性能、可耐受猪胃酸和肠道胆盐环境,对E.coli K88和沙门氏菌具有较好的抑制作用,说明该乳酸菌具有潜在的益生特性。
【OBJECTIVE】 The lactic acid bacteria isolated from porcine intestinal mucosa, chyme and feces were screened for potential probiotic properties by pig lactate production, growth performance, acid and bile salt tolerance and bacteriostasis. 【Method】 A total of 155 strains of lactic acid bacteria were isolated and identified. Among them, 4 strains of lactic acid bacteria with strong acid-producing ability were screened out. The physiological and biochemical tests and bacterial 16S rRNA sequencing were used to identify their species, and the growth of candidate lactic acid bacteria was evaluated. Salt and antibacterial properties. 【Result】 Four strains (L45, L47, L63 and L79) were screened out by comprehensive colorimetric time (8 h), pH value (<3.9) and lactate content (> 100 mmol / L) Lactobacillus, Lactobacillus plantarum, Lactobacillus johnsonii and Enterococcus faecalis. L47 and L79 were able to tolerate acidic environment at pH 2.5, L47 was able to tolerate 0.5% bile salt environment. The lactic acid bacteria supernatants were co-cultured with indicator bacteria and found that L47 and L79 co-cultured with E. coli K88 and Salmonella were inhibited, of which L47 supernatant had a strong inhibitory effect on indicator bacteria. 【Conclusion】 L47 has good acid-producing performance and growth performance, can tolerate pig stomach acid and intestinal bile salt environment, and has good inhibitory effect on E. coli K88 and Salmonella, indicating that L47 has potential probiotic properties.