This study evaluated the antioxidant and protective effects of Hypoxis hemerocallidea
Fisch. & C. A. Mey. (Hypoxidaceae) Corm ('African potato') water extract (HH) against chloroquine induced oxidative stress in albino rats. Chloroquine has been known to generate oxidative stress when used for different types of treatment like malaria, prophylactic treatment and treatment of rheumatoid arthritis. There is also biomedical evidence that African potato corm extracts possess anti-inflammatory, anti-nociceptive, antioxidant and anti-diabetic properties in vivo and in vitro. Twenty five albino rats were used for this study and were divided into five groups; chloroquine control group (CQ) received choroquine (25 mg/kg every day), normal control group (NC) received distilled water every day, normal experimental group (HYP) received water decoction of corm (10 ml/kg), two experimental groups (E1 and E2) received chloroquine (25 mg/kg) plus 10 ml and 20 ml of extract kg-1
body weight respectively. The experiment was conducted for a period of 30 days after which the rats were killed under ether anaesthesia, blood collected and liver removed for the measurement of thiobarbituric acid reactive substance, serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, reduced glutathione, superoxide dismutase, glutathione per-oxidase and tocopherol. The result showed that the water extract maintained the normal non enzymatic and enzymatic anti oxidants status and thus protected the rats in two experimental groups from oxidative stress generated due to chloroquine in dose dependant manner (P≤0.001). The extract also increased the levels of reduced glutathione and tocopherol in HYP group (P≤0.0001). It appears that under normal condition, H hemerocallidea acts as booster plant to antioxidant system increasing the levels of GSH and tocopherol. Thus from this study it can be concluded that H. hemerocallidea has potentials to protect the organism from oxidative stress generated by chloroquine and also to strengthen the antioxidant system under normal conditions.