Abstract

The effects of repeated administration of varying concentrations of the aqueous extract of Eucalyptus globulus leaves on some biochemical parameters of rat liver were studied. Twenty four albino rats (Rattus norvegicus) with a mean weight of 148.35 g were divided into four groups (A - D) of 6 rats each. Rats in group A served as control and were administered 1 ml of distilled water while those of the experimental groups (B - D) were administered varying doses of the aqueous extract (80 mg/kg, 100 mg/kg and 120 mg/kg body weight respectively) for seven days. The activities of acid phosphatase (ACP), alkaline phosphatase (ALP), superoxide dismutase (SOD) and the level of malondialdehyde (MDA) were determined in the liver and serum. ACP and ALP activities were significantly increased (P < 0.05) in the liver with no significant difference (P > 0.05) in their serum activities while the activity of SOD was significantly increased (P < 0.05) in the liver at concentrations of 100 and 120 mg/kg body weight (b.w) of extract. There existed a significant increase (P < 0.05) in the level of MDA in the liver of all the treatment groups and at 120 mg/kg b.w of extract in the serum. Over all, the results indicate that the aqueous extract of E. globulus leaves (despite its efficacy) may have deleterious effects on liver membrane structure and functional integrity.

Key words: Extract, Eucalyptus globulus, lipid peroxidation, enzymes, rat liver.