IN VIVO EVALUATIONS OF THE ANTIDIABETIC AND ANTIOXIDANT EFFECTS OF Olea europaea L. (CHEMLALI VARIETY) LEAVES

Abstract

This study is conducted to evaluate the antidiabetic and antioxidant activities of an aqueous extract of olive leaves (Olea europaea L.) cultivated in the El-Oued region (Southeastern Algeria). Quantitative analysis of polyphenol and flavonoid contents, as well as assessments of antioxidant activity using DPPH•, FRAP, and total antioxidant capacity methods, in addition to the antidiabetic activity were performed. The total contents of polyphenols and flavonoids were found to be 13.7±0.14 mg GAE g of extract and 3.51±0.14 mg QuE g of extract, respectively. In terms of antioxidant activity, the extract demonstrated significant inhibitory effects, with an IC50 value of 23.08±0.12 µg/mL for DPPH•, an EC0.5 value of 37.7±0.05 µg/mL for FRAP, and a total antioxidant capacity of 36.7±0.45 µg AAE/g extract. Diabetes was induced in Wistar albino rats through intraperitoneal injections of alloxan, resulting hyperglycemia, hypercholesterolemia, elevated urea levels, and a depletion in total cholesterol. Administration of an aqueous extract of olive leaves (Olea europaea L.) at a dosage of 200 mg/kg body weight per day over a period of three weeks led to significant reductions in serum glucose and cholesterol levels, and urea concentrations. This study demonstrates that the aqueous extract of Olea europaea L. from the El-Oued region exhibits notable antidiabetic and antioxidant properties.