Anti-diabetic and Toxicological Evaluation of Acetone Fruit-peel extract of Annona muricata in Streptozotocin-induced Wistar rats

Abstract

Medicinal plants have been used since time immemorial for the management of diseases due to their potency, low cost and availability. However, they can be toxic due to their chemical make-up, hence the need for toxicity evaluation. Fruit peels of Annona muricata were collected, authenticated, processed and extracted using maceration technique. Extract was subjected to phytochemical, and antioxidant analyses using Harborne’s method, and DPPH assay respectively. Antidiabetic activity and toxicity on streptozotocin induced diabetic and healthy Wistar rats were analysed by fasting blood glucose levels, acute and sub-acute toxicity tests respectively. Data were analysed and statistical significance was considered when p-value was ˂ 0.05. Bioactive compounds detected included: phenol, tannin, flavonoids, terpenoids, saponin, cardiac glycosides, alkaloids and coumarins. The extracts scavenged free radicals revealed in a dose-dependent manner: 1C50 values range: 34.97 µg/ml -144.86 µg/ml; AAI value range: 5.5-23.5. Acetone had the highest antioxidant capacity (AAI value: 23.5). Mean weight of the diabetic rats treated with normal water declined with a significance difference to those treated with the extracts (p˂0.05). Extracts of A. muricata at 1000 mg/kg reduced blood glucose level of diabetic induced rats from 207.0±1.73a to 87.0±2.65 mg/ dl (n=5), compared with the standard antidiabetic drug 84.7±1.15a (p>0.05) respectively. Death was not observed in both acute and sub-acute toxicity studies, the liver exhibited no anatomical changes, the kidney showed active interstitial congestion and inconspicuous tubular injury. Annona muricata acetone extract exhibited antidiabetic potential with no acute toxicity, but the kidney showed active interstitial congestion and inconspicuous tubular injury.