Optimization of Microwave-Assisted Extraction of Active Com pounds, Antioxidant Activity and Angiotensin Converting En zyme (ACE) Inhibitory Activity from Peperomia pellucida (L.) Kunth

Introduction: to obtain the optimum extraction conditions of total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (AA) and an giotensin converting enzyme (ACE) inhibitory activity from Peperomia pellucida (L.) Kunth. Method: TPC, TFC, AA and ACE inhibitory activity was measured by Folin-Ciocalteu method, AlCl3 method, DPPH and FRAP methods, and ACE kit WST. MAE efficiency parameters used were ethanol concentration, a sample to solvent ratio, extraction time, and microwave power. Results: The optimum conditions of MAE for TPC (49.78 mg GAE/g extract) and TFC (37.18 mg QE/g extract) were 80% ethanol, sample-solvent ratio of 1:12, extraction time of 2 min, MAE power of 30% and 80% ethanol, ratio of 1:12, time of 2 min, and 70% power respectively. The optimum AA was obtained at 65% ethanol, ratio of 1:10, time of 3 min, 50% power (DPPH method), and 65% ethanol, the ratio of 1:12, time of 1 min, and 70% power (FRAP method) respectively. The optimum ACE inhibitory activity (54.73% at a concentration of 100 µg/mL) were obtained at 80% ethanol, ratio of 1:12, time of 2 min, and 70% power. Conclusion: The analysis of Pearson correlation indicated that there was no correlation between TPC with FRAP method; TPC with ACE inhibitory activity and TFC with DPPH method.