In vivo and in vitro antioxidant effects of beetroot pomace extracts

Beetroot pomace, processing by-product from food industry, was investigated in this work. Free radical scavenging activity of Detroit, Cardeal-F1, Egyptian, Bicor and Kestrel beetroot pomace extracts on stable DPPH radicals and reducing power were determinated spectrophotometrically. Detroit beetroot pomace extract (DBPE) showed the best antiradical activity against DPPH radicals (EC50 = 2.06 +/- 0.10 mu g/ml). The reducing power of five beetroot pomace extracts increased with increase in applied concentration. Also, DBPE showed the best reducing power (EC50 = 123.39 +/- 06.05 mu g/ml). In vivo antioxidant and potential hepatoprotective properties were evaluated by following several enzymes (xanthine oxidase, catalase-CAT, peroxidase, glutathione peroxidase-GSHPx and glutathione reductase) activities and measuring the levels of glutathione-GSH and thiobarbituric acid reactive substances (TBARS). The best result in neutralizing the oxidative stress induced by CCl4 was observed upon application of DBPE in doses of 2 and 3 ml/kg body weight. Simultaneous application of DBPE and CCl4 led to a significant decrease in GSHPx level, increase of CAT and GSH levels, turning them to physiological levels of the control group. Phenolics and betalains were identified by HPLC and effected antioxidant and hepatoprotective status. Obtained results indicated that beetroot pomace should be regarded as potential nutraceutic resource and may be used as a functional food ingredient. (C) 2013 Elsevier Ltd. All rights reserved.