Lactiplantibacillus brownii strain MH-1 prolongs healthspan and improves stress resistance in Caenorhabditis elegans.

Lactiplantibacillus brownii was first discovered in 2023. We previously isolated L. brownii strain MH-1 from homemade pickled Chinese cabbage in Hiroshima Prefecture, Japan, and performed whole-genome sequencing. In this study, we examined the beneficial effects of L. brownii strain MH-1 on a host using C. elegans. MH-1 and heat-killed MH-1 extended the lifespan and also alleviated motility decline during aging in worms. Feeding MH-1 to nematodes indicated its presence in the intestinal tract with no change in body or brood sizes, suggesting that dietary restrictions did not occur. There were no significant differences in intestinal barrier enhancement or fat accumulation in MH-1-fed C. elegans. The stress response of C. elegans was enhanced by MH-1 for oxidative stress tolerance. MH-1 increased the expression of genes involved in defense response and lipid catabolism. These results demonstrate the beneficial effects of MH-1 on nematodes and its potential use as a probiotic.