RESUMEN
AIMS: To evaluate the free radical-scavenging capacity of Lactobacillus fermentum and its effects on antioxidant enzyme levels in finishing pigs. METHODS AND RESULTS: The free radical-scavenging activity of Lact. fermentum was analysed in vitro. The tested Lactobacillus showed a high scavenging ability against DPPH (1,1-diphenyl-2-picrylhydrazyl), superoxide and hydroxyl radicals which was dose dependent. Subsequently, 108 crossbred pigs weighing 20.67 BW, were allotted to dietary treatments including a basal diet or the basal diet supplemented with either aureomycin or 10.2 x 10(7) Lact. fermentum CFU g(-1) diet. Supplementation of Lact. fermentum increased total antioxidant capacity (P < 0.01) in serum from 50 kg pigs, while serum superoxide dismutase (P = 0.01) and glutathione peroxidase (P < 0.01) increased, and malondialdehyde levels decreased (P < 0.01) in 90 kg pigs. Hepatic catalase (P = 0.04), muscle superoxide dismutase (P < 0.01) and copper-zinc-superoxide dismutase were enhanced (P = 0.01), whereas malondialdehyde levels were reduced (P = 0.05) by Lact. fermentum. CONCLUSIONS: The free radical-scavenging capacity of Lact. fermentum was dose dependent and its supplementation improved the antioxidant status of pigs. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus fermentum could be used to alleviate oxidative stress and increase pig performance and improve pork quality.