Xiaoyu Chena, Hailan Chena, Yangyan Yin abc, Weiliang Mo d, Zhe Pei e, Huili Bai abc, Zecheng Zuo d*, Hao Peng bc**
aCollege of Animal Science and Technology, Guangxi Key Laboratory of Animal Breeding, Disease Control and Prevention, Guangxi University, Guangxi, Nanning, 530004, China
bGuangxi Key Laboratory of Veterinary Biotechnology, Guangxi Veterinary Research Institute, Guangxi, Nanning, 530001, China
cGuangxi Key Laboratory of China (Guangxi)-ASEAN Cross-Border Animal Disease Prevention and Control, Ministry of Agriculture and Rural Affairs of China, Nanning, 530001, China
dJilin Province Engineering Laboratory of Plant Genetic Improvement, College of Plant Science, Jilin University, Jilin, Changchun, 130062, China e Department of Engineering, Virginia Tech, Blacksburg, VA, 24060, United States
Food Bioscience,Volume 68,2025,106422,ISSN 2212-4292,https://doi.org/10.1016/j.fbio.2025.106422.
Abstract
The rising incidence of antibiotic resistance in Salmonella typhimurium indicates the urgent need for alternative antimicrobial agents. This study aims to identify natural compounds with antibacterial activity against S. typhimurium by screening the fermentation supernatant of Lactobacillus buchneri GX0328-6. Bacteriocins present in the supernatant were fractionated through ultrafiltration using membranes with molecular weight cut-offs of 1, 3, and 10 kDa. Further purification was achieved via gel filtration and reversed-phase high-performance liquid chromatography (RP-HPLC). Through this method, a novel bacteriocin was isolated and designated as GX- 6. Its antimicrobial activity was assessed using the Oxford cup assay after neutralizing the effects of acid and hydrogen peroxide. GX-6 exhibited strong heat resistance, stability within a narrow pH range (pH 2.0–8.0), and a favorable safety profile. At a minimum inhibitory concentration (MIC) of 2 mg/mL, GX-6 effectively eradicated 99.9 % of S. typhimurium within 24 h (p < 0.0001). Scanning electron microscopy revealed that GX-6 disrupted bacterial cell membrane integrity, leading to surface crumpling, intracellular content leakage, and cell rupture.
Thus, the novel bacteriocin, GX-6 demonstrates promising potential as an alternative therapeutic agent for S. typhimurium infectious disease. The main limitation of this work lies on the absence of in vivo evaluation of GX- 6’s antimicrobial activity and the lack of established large-scale industrial production methodologies, which should be fully explored before its widely applications. Thus, the novel bacteriocin, GX-6 demonstrates promising potential as an alternative therapeutic agent for S. typhimurium infectious disease.
Keywords Bacteriocin GX-6;Salmonella typhimurium;Antibacterial activity;Membrane disruption;
Purification;Lactobacillus buchneri