Abstract
Too many ROS accumulate in body without cleanup is one of the risks that promote aging. Therefore, effectively reducing oxidative stress and lowering oxidative damage are important. Polygonum multiflorum Thunb. is one of the most common Chinese herbal medicines. It is known that Polygonum multiflorum Thunb. extract (PME) has excellent antioxidant activity in vitro and in vivo, but the role of antioxidant action of PME is needed to be further explored. In this study, I used budding yeast as model to explore whether PME with different solvent (water and 50% ethanol) could protect yeasts against hydrogen peroxide and heat-induced oxidative stress and after that tested the intracellular ROS production in senescent yeasts. The result showed that PME could reduce yeasts intracellular ROS production in dose-dependent manners under normal growth conditions. Furthermore, pretreating yeasts with 50% ethanol PME could significantly enhance yeasts survival rate after the exposure to high dose hydrogen peroxide and high temperature. Relatively, it also could reduce intracellular ROS production after the exposure to lower dose hydrogen peroxide and lower temperature treatment. Lastly, the data revealed that 50% ethanol PME exhibited antioxidant activity to decrease intracellular ROS production in senescent yeasts and enhance mitochondrial membrane potential. Taken together, these results indicate that 50% ethanol PME can perform antioxidant activity to reduce oxidative stress caused by external and aging process.