Abstract

In a quest for previously unknown aging-delaying (geroprotective) natural chemicals, we used a robust cell viability assay to conduct a screen of a library of commercially available plant extracts. Our screen was aimed at the identification of those plant extracts in the library that can significantly prolong the chronological lifespan of budding yeast. Many of the plant extracts in the library have been used in traditional Chinese and other herbal medicines or the Mediterranean and other customary diets. The screen allowed us to discover fifteen plant extracts that considerably extend the longevity of chronologically aging budding yeast not limited in calorie supply. We demonstrated that each of the fifteen longevity-extending plant extracts is a geroprotector that decreases both the extrinsic and the intrinsic rates of aging in budding yeast. Our findings provided evidence that each of the fifteen longevity-extending plant extracts makes yeast more resistant to chronic (long-term) oxidative and thermal stresses. We also revealed that each of the fifteen geroprotective plant extracts mimics the longevity-extending and stressprotecting effects of a caloric restriction diet in yeast cells that are not limited in calorie supply and age chronologically.