Dietary supplementation of condensed tannin decreased lipid peroxidation in muscle of nile tilapias (Oreochromis niloticus)

Abstract

The effect of condensed tannin supplementation in diet on lipid peroxidation in the muscle was evaluated in Nile tilapias (Oreochromis niloticus). In total, 250 fish, aged 21 days old, were randomly allocated into 10 experimental tanks, 25 fish per tank. Five tanks were set as the control group and 5 tanks as the supplemented group. The control fish were fed a commercial diet, while the supplemented fish were fed the same control diet plus 4 g/kg of condensed tannin. The diets were offered at a rate of 8% of estimated fish body weight twice daily. The experimental period lasted for 120 days. At the end of the experiment, 3 fish from each tank were randomly sampled and euthanized by hypothermic method. Epaxial and hypaxial muscles were collected and divided into 2 subsamples to determine lipid peroxidation by thiobarbituric acid reactive substances (TBARS) assay. The first subsamples were measured for TBARS values immediately after euthanasia within 1 h. The second subsamples were kept at 4C for 48 h before TBARS value determination (48 h). Average TBARS values measured at 1 h post euthanasia were lower in the supplemented fish [0.2690.028 mg malondialdehyde (MDA)/kg of fresh meat] than in the control fish (0.4800.025 mg MDA/kg). Similar results were also observed for TBARS values measured at 48 h. In conclusion, the dietary supplementation of condensed tannin significantly reduced lipid peroxidation in the muscle.