Study of Phytochemistry, Toxicity and Antihypertensive Activity of Carpobrotus Edulis Aqueous Leaf Extract

Abstract

Carpobrotus edulis is a medicinal plant widely used as a folk medicine in Southern Africa, to treat hypertension and other ailments. Despite its extensive use in herbal medicine, there is no documented scientific evidence corroborating its safety or any that validates its therapeutic use in hypertension treatment. Therefore, the aims of this study were to investigate the antihypertensive effects of aqueous extracts of Carpobrotus edulis in fructose-induced hypertensive rat models and also to determine the toxicological effects of both acute and subacute exposure to aqueous extracts of Carpobrotus edulis in Sprague Dawley rats. Aqueous extraction and phytochemistry of Carpobrotus edulis leaves was performed by using standard routine methods. The acute and subacute toxicity evaluation of the aqueous extract of Carpobrotus edulis was done using established methods (OECD guidelines). In acute toxicity testing, a single oral exposure of the extract was given to three healthy female Sprague Dawley rats at the four fixed dose levels of 300, 600, 1200 and 2000 mg/Kg body weight. The rats were observed clinically for any signs of toxicity for a period of 24 hours. These Sprague Dawley rats were then kept for 14 days and were weighed weekly. On the fourteenth day, the animals were euthanized using chloroform and gross necropsy was performed on all animals. For the subacute toxicity study, thirty-two (32) Sprague Dawley rats of both sexes equally represented, were grouped into three treatment groups (A-C) and one negative control group D of eight animals each. Group A received 100 mg/Kg of the extract; Group B received 300 mg/Kg while Group C received 1000 mg/Kg of the extract for 28 days. The rats were weighed prior to dosing at weekly intervals and the weight of each rat recorded separately. Feed and water consumption were also measured on a weekly basis. After the 28th day, the effect of Carpobrotus edulis on organs, haematological and biochemical parameters were assessed...