Isolation and safety evaluation of food-derived potential probiotic Bacillus with antimicrobial properties

• Published in: Microbial pathogenesis Vol. 201; p. 107338
• Main Authors: Hu, Maoling, Jiao, Rui, Zhang, Xiyan, Li, Hui, Ren, Yuwei, Wang, Yang, Ling, Na, Ye, Yingwang
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2025
• Subjects: Animals; Anti-Bacterial Agents - pharmacology; antibacterial properties; antibiotic resistance; Antimicrobial activity; B. subtilis YH91-2; Bacillus - classification; Bacillus - genetics; Bacillus - isolation & purification; Bacillus - physiology; Bacillus subtilis - genetics; Bacillus subtilis - isolation & purification; Beneficial properties; cytotoxicity; DNA; DNA, Bacterial - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; enzyme activity; fermentation; fermented foods; Fermented Foods - microbiology; food industry; Food Microbiology; Gram-Negative Bacteria - drug effects; Gram-Positive Bacteria - drug effects; Growth promotion; Male; Mice; Microbial Sensitivity Tests; nutrition; pathogenesis; probiotics; Probiotics - administration & dosage; Probiotics - adverse effects; Probiotics - isolation & purification; Probiotics - pharmacology; RNA, Ribosomal, 16S - genetics; Safety evaluation; triacylglycerols; weight gain; Beneficial properties; Antimicrobial activity; B. subtilis YH91-2; Growth promotion; Safety evaluation
• ISSN: 0882-4010; 1096-1208; 1096-1208
• DOI: 10.1016/j.micpath.2025.107338

Traditional Chinese fermented foods, known for their probiotic content and microbial diversity, contribute significantly to dietary nutrition. This study aimed to assess the safety and antimicrobial potential of Bacillus isolated from these foods for industrial applications. Evaluating the antimicrobial activity and safety of probiotics such as Bacillus is imperative for application in the fermented food industry. Sixty Bacillus strains were isolated from 60 fermented food samples and confirmed by 16S rDNA testing. Of these, 39 were identified as non-toxic based on PCR screening, suggesting a favorable safety profile for consumption. Among the pathogens tested, B. subtilis YH91-2 demonstrated the most potent antibacterial activity against both Gram-positive (n = 2) and Gram-negative (n = 7) bacteria. Comprehensive analyses of hemolytic evaluation, DNA enzyme activity, antibiotic susceptibility, cytotoxicity tests, and tolerance to unfavorable conditions, B. subtilis YH91-2 had the potential as a promising probiotic. Besides vitro evaluation, the effects of B. subtilis YH91-2 in vivo safety were also examined. No harmful health effects were observed in mice irrigating with high, medium, and low doses of YH91-2 for 21 days. Notably, mice receiving high doses showed significant weight gain and a marked decrease in triglyceride levels compared to control subjects. The results provided compelling evidence for the potential of B. subtilis YH91-2 as a probiotic for advancing food industry applications. •A safe strain of B. subtilis YH91-2 was isolated from traditional fermented food.•B. subtilis YH91-2 had the most potent antibacterial activity against both Gram-positive (n = 2) and Gram-negative (n = 7) bacteria.•It has a high survival rate under various stresses.•Feeding high concentration of B. subtilis YH91-2 can promote the increase of body weight and the decrease of triglyceride content in mice.