Tapinanthus globiferus (A. Rich.) Tiegh. leaf extract and the antioxidant vitamins in heat-driven oxidation of beef meat in rats

Abstract

Boiling and frying make meat suitable for consumption. This study evaluated oxidative changes in boiled and fried meat (180-200°C) and the antioxidant effect of Tapinanthus leaf extract in rats. Animals were assigned to groups A to E (n-4). Group A (control) took distilled water; the experimental groups B to E either received fried beef floss feed supplement, an oxidized lipid diet (OLD) and different treatment per kg body weight for two weeks as follows: Groups B (400 mg extract), C (33.33% OLD), D (OLD + 400 mg extract) and E (OLD + 1000 mg vitamin E). The extract showed detectable levels of polyphenols, cardiac glycosides and phytosterols, and demonstrated superoxide dismutase, catalase and glutathione antioxidant activities in a concentration-dependent manner. The beef floss contains high levels of free fatty acids, peroxides and carbonyl compounds. However, serum levels of vitamins E, C and A and malondialdehyde were not significantly (p>0.05) different between the groups, F = 1.45, 1.39, 1.93 and 2.44, respectively. The findings suggest that frying boiled beef meat promotes loss of fat and protein constituents and the formation of potential pro-oxidants, which did not influence the supposed required antioxidant potentials in Tapinanthus globiferus. Hence, recommending further studies on higher and chronic supplementation.