In-depth genomic identification and safety evaluation of Lactobacillus Acidophilus LA85

• Published in: Journal of functional foods 2024-12, Vol.123, p.106604, Article 106604
• Main Authors: Qi, Yongmei, Dong, Yao, Gu, Jiayue, Cai, Yihui, Zhang, Yanyan, Gai, Zhonghui, Han, Mei
• Format: Article
• Language: English
• Subjects: Lactobacillus acidophilus; Metabolites; Probiotics; Safety assessment; Toxicity; Whole genome sequencing
• ISSN: 1756-4646
• DOI: 10.1016/j.jff.2024.106604

In vitro tests assessed heat tolerance, bile salt hydrolysis, intestinal adhesion, gastrointestinal environmental tolerance, hemolysis, gelatin hydrolysis, antibiotic sensitivity, inhibition of pathogenic bacteria, and toxicity of Lactobacillus acidophilus LA85. The safety of LA85 was verified by acute oral toxicity test. Genome analysis revealed no virulence, pathogenicity, or biogenic amine synthesis genes in LA85, but one drug resistance gene. LA85 displayed strong heat tolerance, intestinal adhesion, and gastrointestinal environment tolerance, with bile salt and gelatin hydrolysis abilities, and no hemolysis. It was sensitive to European Food Safety Authority proposed antibiotics, had inhibitory effects on common pathogenic bacteria, and both its fermentation broth and cells were non-toxic. Acute oral toxicity test confirmed that LA85 (2 × 1010 CFU/kg) was safe and non-toxic in mice. The safety evaluation presented in this paper firmly establishes LA85 as a safe and effective probiotic candidate for use in a wide range of food and medical applications. Graphical abstract [Display omitted] •Genome analysis revealed no virulence, pathogenicity, or biogenic amine synthesis genes in LA85.•Both fermentation broth and cells of LA85 were non-toxic.•Acute oral toxicity test confirmed that LA85 (2 × 1010 CFU/kg) was safe and non-toxic in mice.