Safety Evaluation of Methanol Leaf Extract of Canavalia ensiformis (Fabaceae): Acute Oral Toxicity Assessment in Rats Using the Up-and-Down Procedure

Résumé

Background: Medicinal plants continue to serve as important therapeutic resources in traditional medicine. Canavalia ensiformis (L.) DC. (Fabaceae), commonly known as jack bean, is traditionally utilized in several tropical regions, including Nigeria, for nutritional and medicinal purposes. This study aimed to evaluate the acute oral toxicity profile of the methanol leaf extract of Canavalia ensiformis in female Sprague–Dawley rats.

Methods: Acute toxicity was evaluated using the Organisation for Economic Co-operation and Development (OECD) Test Guideline 425 (Up-and-Down Procedure). Ten nulliparous and non-pregnant female Sprague–Dawley rats (185 ± 7.08 g) were randomly divided into control and treated groups (n = 5). The treated group received a single oral limit dose of 2000 mg/kg of the methanol leaf extract, while the control group received distilled water. Animals were monitored for behavioural changes, signs of toxicity, and mortality for 14 days. At the end of the study, animals were sacrificed and the liver and kidneys were harvested for histopathological evaluation using haematoxylin and eosin staining.

Results: No mortality or overt behavioural signs of toxicity were observed during the 14-day observation period. Histopathological examination revealed portal-associated hepatic necrosis and atrophy of Bowman’s corpuscles in the kidney, suggesting structural alterations in these organs at the tested dose.

Conclusion: These findings suggest possible organ-specific toxicity at high doses and highlight the need for further subacute and chronic toxicity studies to establish safe therapeutic dose ranges.