Lactobacillus reuteri is one of the most largely studied human-commensal bacteria and widely used as a form of probiotics. Safety of probiotics has become increasingly important for human consumption due to increasing health-concerns in food industry. In this study, the safety of L. reuteri IDCC 3701 isolated from human breast milk was thoroughly investigated. Whole-genome sequence analysis was performed to identify antibiotic resistance and toxigenicity of L. reuteri IDCC 3701. Phenotypic analysis such as minimal inhibitory concentration, β-hemolysis, extracellular enzyme activity, and the production of biological amines and L/D-lactate, was investigated. Finally, acute oral toxicity test was performed to access L. reuteri IDCC 3701 safety. Although multiple resistances to gentamicin and kanamycin were observed in L. reuteri IDCC 3701, it was revealed that these resistances are intrinsic and not transferable through whole-genome analysis. In addition, various phenotypic analysis concerning hemolysis, enzyme activity, and D-lactate production did not show any negative results. Although L. reuteri IDCC 3701 harbors a histidine decarboxylase gene, no biogenic amines were detected. Finally, L. reuteri IDCC 3701 exhibited no evidence of acute toxicity according to an in vivo study. Our findings demonstrate that L. reuteri IDCC 3701 is considered to be safe for human consumption as probiotics based on the in silico, in vitro and in vivo studies.

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基于表型和基因组分析的罗伊氏乳杆菌IDCC 3701安全性评估

罗伊氏乳杆菌是研究最多的人类共生细菌之一，被广泛用作益生菌。由于食品行业对健康的关注越来越大，益生菌的安全性对于人类食用而言变得越来越重要。在这项研究中，彻底研究了从人母乳中分离出的罗伊氏乳杆菌IDCC 3701的安全性。进行全基因组序列分析以鉴定罗伊氏乳杆菌IDCC 3701的抗生素抗性和产毒性。调查。最后，进行急性口服毒性试验以获取罗伊氏乳杆菌IDCC 3701的安全性。尽管在罗伊氏乳杆菌IDCC 3701中观察到对庆大霉素和卡那霉素的多重耐药性，据揭示，这些抗性是内在的，不能通过全基因组分析转移。此外，有关溶血，酶活性和D-乳酸生成的各种表型分析未显示任何阴性结果。尽管罗伊氏乳杆菌IDCC 3701包含组氨酸脱羧酶基因，但未检测到生物胺。最后，根据体内研究，罗伊氏乳杆菌IDCC 3701没有表现出急性毒性的证据。我们的发现表明，基于计算机模拟，体外和体内研究，罗伊氏乳杆菌IDCC 3701作为益生菌被认为对人类食用是安全的。尽管罗伊氏乳杆菌IDCC 3701包含组氨酸脱羧酶基因，但未检测到生物胺。最后，根据体内研究，罗伊氏乳杆菌IDCC 3701没有表现出急性毒性的证据。我们的发现表明，基于计算机模拟，体外和体内研究，罗伊氏乳杆菌IDCC 3701作为益生菌被认为对人类食用是安全的。尽管罗伊氏乳杆菌IDCC 3701包含组氨酸脱羧酶基因，但未检测到生物胺。最后，根据体内研究，罗伊氏乳杆菌IDCC 3701没有表现出急性毒性的证据。我们的发现表明，基于计算机模拟，体外和体内研究，罗伊氏乳杆菌IDCC 3701作为益生菌被认为对人类食用是安全的。