The ultraviolet (UV) protective effects of aqueous herb extracts from Latin America such as Yerba Mate (Ilex paraguariensis), Chancapiedra (Phyllanthus niruri L.) and Huacatay (Tagetes minuta) were assessed by using the UV light-induced cell death in Saccharomyces cerevisiae yeast model. UV radiation-mediated oxidative stress promoted cell death of S. cerevisiae by inducing breakdown of its energy metabolism. The addition of high-phenolic herb extracts (61-103mg gallic acid equivalents/g dw) prior to UV treatment protected yeast from UV-induced oxidative stress and delayed death. This effect appeared to be related with the high free radical scavenging activities shown by all extracts (91%). Insights into the UV protective mechanisms of Yerba Mate extract in yeast model indicated that protection was achieved by maintaining the growth-supporting tricarboxylic acid cycle/NADH-linked system and the proline-linked mitochondrial oxidative phosphorylation coupled to pentose phosphate pathway. Therefore, studied herb extracts show potential protective properties against UV radiation-induced yeast death. © 2011 Wiley Periodicals, Inc.