SAFETY PROFILE AND ANTIOXIDANT ACTIVITY OF THE ETHANOL LEAF EXTRACT AND FRACTIONS OF Spondias mombin LINN, FAMILY ANARCADIACEAE

Spondias mombin is used ethnomedicinally in Nigeria and other parts of the world in the treatment of various diseases including epilepsy and schizophrenia. In this study, we investigated acute and sub-chronic toxicity of ethanol extract as well as in vitro and in vivo antioxidant activities of ethanol extract and fractions of Spondias mombin leaf. Acute and 90 days sub-chronic effects of the extract were investigated. The ability of the extract and fractions to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (0.6 Mmol) was used to assess their in vitro antioxidant activities while in vivo antioxidant activity was evaluated using carbon tetrachloride (CCL4) (1.5 ml/kg) induced oxidative stress model. Acute toxicity studies of the extract showed the lethal dose (LD50) to be above 5000 mg/kg body weight. The test extract and fractions exhibited potential scavenging effects on DPPH radical with methanol fraction exhibiting the highest scavenging activity (IC50 2 μg/ml). CCL4 decreased serum levels of antioxidant enzymes (catalase, superoxide dismutase) and increased the formation of malondialdehyde (MDA) in untreated animals while significant (P<0.05) increases in these enzymes and decrease in MDA were observed in the treatment groups, with the methanol fraction exhibiting the highest in vivo antioxidant effect even more than the positive control. The extract (750 mg/kg, 1500 mg/kg and 3000 mg/kg) showed no significant (P>0.05) effect on haematological and biochemical parameters. Histopathological studies showed no obvious pathological changes in the liver and kidney architecture of extract treated rats when compared to those of the control group.