Effects of microwave extraction conditions on polyphenol content and antioxidant activity of pomelo extract (Citrus maxima (Burm.)Merr.)

Abstract

The albedo, white peel of pomelo Citrus maxima (Burm.)Merr., is by-product of food processing, and has polyphenol and antioxidant activity. However, there are not many studies on polyphenol from pomelo peel in Vietnam by microwave extraction. Microwave-assisted extraction helps more efficient heating, faster energy transfer, increasing or decreasing temperature control, saving solvent and cost to extract active ingredients from plant materials. This research applied microwave extraction to extract polyphenol from pomelo Citrus maxima (Burm.)Merr. The factors that affected the extraction process such as solvent concentration, microwave power, extraction time and material to solid ratio were investigated. The results obtained that the highest polyphenol content (2.46 gGAE/L) and antioxidant activity (1325.85 µmolTE/L) with ethanol concentration of 60%, microwave power of 300W, microwave-assisted time of 2 minutes, and material to solvent ratio of 1:30.