Green Extraction of Polyphenols from Olive Leaves using Ired-Irrad® as a Pretreatment

Abstract

Maximization of polyphenols recovery from olive leaves by conventional water bath extraction was investigated using infrared irradiation as a pretreatment. A multivariate study enabled us to define the best experimental parameters for polyphenol extraction: 1:20 (w/v) for the solid to liquid ratio; $60 ^{\circ}\mathrm {C}$ and 75% ethanol/water. Untreated and infrared pretreated leaves were then subjected to the conventional extraction of polyphenols using the abovementioned conditions. A significant increase in both polyphenol yields and antiradical activities were shown subsequently to the infrared pretreatment of the leaves. This study concluded that IR pretreatment intensified the polyphenols extraction by varying different operative parameters such as temperature and IR exposure time.