1株人源抑制致病菌的粪肠球菌性能评价

Evaluation of a human derived anti-pathogenic Enterococcus faecalis to inhibit pathogenic bacteria

目的对分离自健康成人粪便中的一株粪肠球菌QT01进行生物学性质和抑制致病菌能力评价。方法采用PCR方法扩增16S rDNA基因并测序确定分离菌株的种属;采用药敏试验和耐酸耐胆盐试验评价QT01对抗生素敏感性及耐受胃肠道能力;采用抑制试验评价QT01拮抗致病菌和益生菌的能力。结果经16S rDNA序列同源性分析,鉴定该菌株为粪肠球菌(Enterococcus faecalis);它不耐酸,但具有较强的耐胆盐能力;对常见抗生素如阿莫西林、青霉素、氯霉素和环丙沙星等敏感;能抑制粪肠球菌致病株V583和产气肠杆菌,但不能抑制植物乳杆菌和嗜热链球菌。结论粪肠球菌QT01不耐酸耐胆盐,对抗生素敏感,能够抑制致病菌V583,在微生态制剂产品开发方面具有应用潜力。

Objective To analyze the traits of an Enterococcus faecalis strain QT01 isolated from healthy human feces.Methods 16S rDNA gene sequencing was used to detect the species of the isolated strains from human feces;the antibacterial effect of QT01 and its tolerance to antibiotics,gastric acid and bile salts were examined by antibacterial test,drug sensitivity test and acid and bile salt test,respectively.Results After 16S rDNA sequence homology analysis,QT01 was identified as Enterococcus faecalis.QT01 had high bile salt tolerance and was sensitive to common antibiotics including amoxicillin,penicillin,chloramphenicol and ciprofloxacin,etc.QT01 also inhibited the growth of pathogenic bacteria V583 and enterobacter aerogenes,but not Lactobacillus plantarum or Streptococcus thermophilus.Conclusion The current study has identified a novel Enterococcus faecalis QT01,which has a fast growth rate and can inhibit pathogenic bacteria.QT01 has the potential being developed as microecological preparation products.