Liver antioxidant status
The antioxidant status in liver homogenates suggests that supplementation with TCMN stimulated the antioxidant system in the liver to counteract the oxidative damage caused by AFB1. Aflatoxin B1 is a potent carcinogen that forms adducts with DNA, induces cellular oxidative
damage(31) and causes lipid peroxidation in liver(32).Supplementation of root extracts of Picrorhiza kurroa and seeds of Silybum marianum enhanced the activity of antioxidant enzymes and reduced peroxide levels in liver of rats fed AFB1(33). The carbonyl functional group of curcuminoids from turmeric was shown to be responsible for its antimutagenic and anticarcinogenic action(34). Moreover, curcumin has been shown to strongly inhibit superoxide anion generation(35) and biotransformation of AFB1 to aflatoxicol in liver(9). These findings support the hypothesised action of curcuminoids as antioxidants, and the results of the present study suggest that 222mg/kg TCMN provided maximum protection against AFB1. Free radicals, apart from initiating lipid peroxidation, also release cytoplasmic Ca2þ that plays a crucial role in subsequent propagation of tissue injury, and hence protection against oxidative stress cannot be completely achieved by the action of radical scavenging antioxidants alone(36).