The aim of this research was to determine in vitro the antibacterial, antioxidant and tanning activity from grape by-products (Vitis vinifera), for its use as alternative ingredients in the poultry industry and food conservation. Polar compound had been extracted of the defatted grape seed (SUD) in a solution with acetone, water and acetic acid, in the 90: 9.5: 0.5 ratio respectively, resulting in a yield of 10.3% of defatted grape seed extract (ESUD). ESUD has high antibacterial activity against strains of S. aureus and E. coli, but not against Salmonella sp. The antioxidant activities of the ESUD had comparable to the ascorbic acid. The capacity to bind proteins was considered low for the seed and high for the ESUD.
antimicrobial activity; antioxidant activity; grape by-products; tannins