Improving the recovery of phenolics and flavonoids from Coriandrum sativum L. leaves using microwave-enzymatic-assisted extraction

Abstract

This study focused on optimizing the extraction of phenolic compounds and flavonoids from leaves of Coriandrum sativum L. using a sequential green extraction approach based on microwave-enzymatic-assisted extraction (MEAE). Utilizing the Glycerol and Choline Chloride solvent system (composed of Gly -Cho in a molar ratio of 2:1, with 10% water), several extraction parameters were systematically investigated for their influence on total phenolic content (TPC) and total flavonoid content (TFC): solid-to-liquid ratio, water content, microwave power, microwave time, enzyme concentration, and enzyme incubation time. Subsequent optimization established the following conditions: a solid mass of 1/20 g/mL, 10% water content in solvent, 728 W microwave power, 3 minutes microwave time, 30 U/g enzyme concentration, and 90 minutes enzyme incubation time. Under these optimized parameters, TPC of the extracts reached 18.15 mg rutin equivalent per gram of dry weight (mg RE/g dw), and the TFC reached 14.52 mg equivalent per gram of dry weight (mg /g dw). The significance of variables was evaluated using Plackett-Burman Design, while optimal conditions were determined via Box-Behnken Design. Furthermore, the extraction kinetics were modeled using a second-order kinetic model to understand the mechanism. The findings demonstrate that the sequential MEAE technique, optimized via statistical and kinetic models, holds significant promise as an effective green method for enhancing the recovery of antioxidant compounds from Coriandrum sativum L.