Vania Lizett Lucas-Hernández

The food industry has a strong interest in lactic acid bacteria (LAB) because of their probiotic potential and health advantages. LAB have been previously isolated from pulque and agave sap, showing antibacterial action. However, their reaction to stress can limit their survivability, and their biological activities are strain-specific. To ascertain the impact of LAB isolated from pulque and agave sap on lifespan, thermal and oxidative stress, and health span parameters, we fed the nematode Caenorhabditis elegans these bacteria. The nematodes fed the Escherichia coli OP50 strain were utilized as a control for each experiment. Animals were fed each strain for four days starting from L4 and either (day 5) exposed to oxidative stress caused by high hydrogen peroxide concentrations (8 mM) or acute heat stress (35 °C) for four hours. The strains Lacticaseibacillus rhamnosus and Lactiplantibacillus plantarum significantly improved lifespan, fertility, movement, and heat shock resistance. Lacticaseibacillus casei enhanced the C. elegans lifespan, and Levilactobacillus brevis only increased its survivability in the heat shock studies. Interestingly, we discovered a harmful impact on animals fed Pediococcus acidilactici. This study highlights that, even when strains come from the same plant source, their biological activity might differ significantly.