Lactiplantibacillus plantarum, previously named Lactobacillus plantarum, is a facultative, homofermentative lactic acid bacterium widely distributed in nature. Several Lpb. plantarum strains have been demonstrated to possess good probiotic properties, and Lpb. plantarum HOM3204 is a potential probiotic strain isolated from homemade pickled cabbage plants. In this study, whole-genome sequencing was performed to acquire genetic information and predict the function of HOM3204, which has a circular chromosome of 3,232,697 bp and two plasmids of 48,573 and 17,060 bp, respectively. Moreover, various oxidative stress-related genes were identified in the strain, and its antioxidant activity was evaluated in vitro and in vivo. Compared to reference strains, the intracellular cell-free extracts of Lpb. plantarum HOM3204 at a dose of 1010 colony-forming units (CFU)/ml in vitro exhibited stronger antioxidant properties, such as total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl radical scavenging rate, superoxide dismutase activity, and glutathione (GSH) content. Daily administration of 109 CFU Lpb. plantarum HOM3204 for 45 days significantly improved the antioxidant function by increasing the glutathione peroxidase activity in the whole blood and GSH concentration in the livers of D-galactose-induced aging mice. These results suggest that Lpb. plantarum HOM3204 can potentially be used as a food ingredient with good antioxidant properties.
Keywords: D-galactose-induced aging; Lactiplantibacillus plantarum; antioxidant activity; oxidative stress; whole genome sequence.