Acute and Sub-acute Toxicity Evaluation of Methanolic Leaf Extract of Corchorus olitorius in Experimental Animal Models

Aim: In this study, the oral toxicity potential of Corchorus olitorius leaf extract was evaluated in rats.

Methods: Acute and sub-acute toxicity studies were carried out on different sets of rats treated with graded doses of the extract. In the acute toxicity study, forty five albino mice assigned to nine groups of five mice each were administered different doses of the extract ranging from 500 mg/kg body weight to 8000 mg/kg body weight and were observed for toxicity signs and mortalities. For the sub-acute toxicity study, four groups of rats were assigned treatments. While group 1 rats served as the control, groups 2, 3 and 4 were the test groups and were administered 250, 500 and 1000 mg/kg body weight of the extract respectively for 28 days.

Results: The results of acute toxicity evaluation indicated an LD50 value of 7100 mg/kg. In the sub-acute toxicity study, no significant difference was observed between relative organ weights for test groups at lower dose treatments (P>0.05). Basal Metabolic Index values were significantly lower in all test groups (P<0.05). RBC count, PCV values and haemoglobin concentrations were significantly increased following treatment except in the 1000 mg/kg treated group where a decline was observed with a concurrent increase in white blood cell count. Platelet count was also significantly lowered in the 1000 mg/kg body weight treatment group (P<0.05). Serum urea, creatinine, AST, ALT, ALP, total protein and serum electrolyte concentrations were all significantly elevated in the 1000 mg/kg extract treated group (P<0.05). Liver sections showed some degree of liver damage when compared with control, while kidney sections were intact in all test groups.

Conclusion: Hence, low to moderate consumption of Corchorus olitorius leaves extract may cause no toxic effects to the blood, liver or kidney. However, high dose administrations over a long period of time may pose threats of toxicity to the blood and liver.