Optimization of Extraction of Phenolic Compounds from Ocimum Basilicum Leaves and Evaluation of Their Antioxidant Activity

Basil (Ocimum basilicum L.) is a potential source of bioactive compounds with various pharmaceutical effects. This study was aimed to extract phenolic compounds from basil leaves and evaluate the antioxidant activity of the extract. Different solvents (methanol, ethanol, acetone, and distilled water) were used to extract the phenolic compounds. Among solvents tested, methanol was the most potent solvent for extraction. The extraction was subsequently optimized using the response surface methodology for maximizing the total phenolic content (TPC). The optimum conditions were found to be the methanol to sample ratio of 44.6 mL/g, methanol concentration of 39%, extraction temperature of 90.7°C, and extraction time of 3.15 h for the maximum TPC of 4.49 mg GAE/g DW. The obtained phenolic-rich extract was then studied for its antioxidant activity. Results showed that the basil leaf extract possessed a high antioxidant capacity with IC50 value of 285.36 μg/mL. This study suggests that basil is a promising source of phenolic compounds and the basil leaf extract is a potential antioxidant agent for pharmaceutical use.