犬源益生菌的筛选及特性研究

Screening and characterization of lactic acid bacteria from canine

本试验从健康的成年犬粪便中分离出11株菌株,采取抑菌试验筛选得到5株动物乳杆菌(Lactobacillus animalis) B5、B8、B9、B10、B11。5株菌株均有着良好的生长优势、产酸能力和自由基清除能力。菌株B5和B11在pH 2.0环境中的生存能力达50%以上;在0.3%胆盐浓度下,5株菌株存活率高于70%;B8有较强的自凝聚能力,5 h可达到63.78%;B9的表面疏水能力高达90.07%;5株菌株对青霉素、氯霉素、环丙沙星、氨苄西林普遍高度敏感,对庆大霉素、丁胺卡那、复方新诺明、四环素及万古霉素不敏感;溶血试验表明所选动物乳杆菌为无毒菌株。因此,这5株动物乳杆菌可作为潜在的益生菌菌株应用于犬食品中。

In this study,11 strains were isolated from the feces of healthy adult dogs.Five strains of Lactobacillus animalis,namely B5,B8,B9,B10 and B11 were selected via antimicrobial testing.Further research revealed that five strains of Lactobacillus animalis exhibited favorable growth rates,acid production abilities,and DPPH radical scavenging activities.What’s more,the survival rate of five strains exceeded 70%when exposed to a bile salt concentration of 0.3%.Meanwhile,the survival rates of B5 and B11 exceeded 50%under pH 2.0 conditions.Among the five strains,B8 demonstrated a strong ability to self-coagulate,achieving a rate of 63.78%within 5 h,while B9 exhibited high surface hydrophobicity with a test result of up to 90.07%.In addition,the five strains exhibited high sensitivity to penicillin,chloramphenicol,ciprofloxacin,and ampicillin;however,they were found to be insensitive to gentamicin,amikacin,cotrimoxazole,tetracycline and vancomycin.Furthermore,the hemolysis test demonstrated the safety of the selected Lactobacillus animalis.Therefore,the five strains of Lactobacillus animalis exhibit potential as probiotic candidates for dog food application.