Peptides with health-promoting activities are present in various fermented foods and beverages. Among their most important beneficial properties are antihypertensive activity and antioxidant activity. In the present work, we investigated the ability of Oenococcus oeni strain m isolated from wine to increase the concentration of peptides with beneficial biological activity from the nitrogen fraction of four Argentine wine varietals (Cabernet Sauvignon, Malbec, Tannat and Torrontés). We demonstrate that O. oeni m, under nutritional stress conditions, produces an extracellular protease that hydrolyzes wine proteins releasing peptides and increasing antioxidant, antiradical and antihypertensive activities. Inoculation of O. oeni m in synthetic wine medium supplemented with the high molecular weight nitrogenous fraction of the four wine varietals under conditions similar to those of natural winemaking showed that the extracellular protease of the microorganism hydrolyzes wine proteinsreleasing mainly peptides.