Safety assessment of Lactobacillus reuteri IDCC 3701 based on phenotypic and genomic analysis

• Published in: Annals of microbiology Vol. 71; no. 1
• Main Authors: Lee, Bo Som, Ban, O-Hyun, Bang, Won Yeong, Chae, Seung A, Oh, Sangki, Park, Chanmi, Lee, Minjee, Kim, Soo-Jung, Yang, Jungwoo, Jung, Young Hoon
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 15.02.2021; Springer; Springer Nature B.V
• Subjects: Acute toxicity; Amines; Analysis; Antibiotic resistance; Antibiotics; Applied Microbiology; Bacteria; Biogenic amines; Biomedical and Life Sciences; Breast milk; Drug resistance in microorganisms; Enzymatic activity; Enzymes; Food industry; Genes; Genomes; Genomic analysis; Genomics; Gentamicin; Hemolysis; Histidine; Histidine decarboxylase; Kanamycin; Lactic acid; Lactobacillus reuteri; Life Sciences; Medical Microbiology; Microbial Ecology; Microbial Genetics and Genomics; Microbiology; Mycology; Nucleotide sequence; Probiotics; Safety; Sequence analysis; Short Communication; Toxigenicity; St Louis Missouri; United Kingdom > UK; United States > US; Probiotics; Lactic acid bacteria; Safety evaluation
• ISSN: 1590-4261; 1869-2044
• DOI: 10.1186/s13213-021-01622-y

Purpose 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. Methods 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. Results 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. Conclusion 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.