Optimization of Phenolic Compound Recovery and Antioxidant Activity of Bay Leaves using Sequential and Response Surface Methodologies

Abstract

Background:The laurel is a shrub native to the Mediterranean basin. It is too often wrongly relegated to the kitchen as a simple condiment while it possesses many therapeutic properties and virtues. The valorization of this plant in terms of bioactive compounds seems to be important.Objective:The aim of the present study is to optimize total phenolic content (TPC) extraction and antioxidant activity from dried bay leaves using conventional process and response surface methodology (RSM).Method:The study of optimization firstly tested three extraction methods (maceration, ultrasonicassisted extraction (UAE), and Microwave-assisted extraction (MAE)) then the best one was considered for RSM.Results :The results for the sequential procedure indicated that MAE was the best method for TPC extraction and antioxidant activity of Laurus nobilis leaves. The mathematical modeling of MEA using response surface methodology showed that optimal conditions for phenolic compounds extraction were 57% methanol with microwaves power of 602W during 3.48 minutes. These conditions allowed TPC extraction of 83.53 mg/g and manifested an antioxidant activity of 32.51 mg EAG/g.Conclusion:The validation of models indicated that experimental values were in accordance with predicted ones, demonstrating the suitability of developed models and the success of RSM in the optimization of antioxidants extraction from Laurus nobilis leaves. Therefore, the bay leaves could be considered as an interesting source of phenolic antioxidants.