Toxicological Evaluation of Methanolic Leaf Extract of Calotropis procera (Ait.) R. Br. on Selected Biochemical Parameters in Rats

Abstract

The methanolic leaf extract of Calotropis procera was investigated for its toxicological effect on selected biochemical parameters in rats. Forty five albino rats of both sexes were used for the research work. For the acute toxicity study (LD50), fifteen animals were completely randomized into three groups (A-C) comprising 5 animals each. Animals in group A were administered 1 ml of 500 mg/kg body weight of the extract while those in groups B and C received 1000 and 1500 mg/kg body weight of the extract respectively. Signs of toxicity and number of death were observed and recorded for 14 days. In the experimental design, twenty five fresh animals were completely randomized into five groups (A-E) comprising 5 animals each. Animals in group A (control) were administered 1 ml of distilled water while those in groups B, C, D and E were respectively administered 100, 300, 600 and 1000 mg/kg body weight of the methanolic leaf extract of C. procera once daily for 7 days. Preliminary phytochemical screening revealed that the methanolic leaf extract of C. procera contains alkaloids, flavonoids, tannins, saponins, steroids, phlobatannins and cardiac glycosides. LD50 of the extract was found to be safe up to 1500 mg/kg body weight. When compared with the distilled water treated control animals, the methanolic leaf extract of C. procera at all doses significantly (p<0.05) increased the concentrations of both total and conjugated bilirubin in the serum of the animals in a dose related manner. Treatment with the extract at all doses significantly (p<0.05) increased the activity of AST in the liver, kidney and serum of the animals in a dose related manner. Administration of the extract at all doses significantly (p<0.05) increased the activity of ALT in the liver and serum of the animals also in a dose related manner. The extract at all doses significantly (p<0.05) decreased the activity of ALT in the heart of the animals. Overall, the methanolic leaf extract of C. procera which caused alterations in the biomolecules may affect the normal functioning capacity of the tissues; therefore, it may not be completely ‘safe’ as oral remedy at the doses investigated in this study.