Extraction of Polyphenolic and Volatile Compounds from Cistus creticus Using Deep Eutectic Solvents and Pulsed Electric Fields

Abstract

To date, many studies have been published, aiming to extract bioactive compounds from plants. Lately, research focuses on maximizing the extraction yield, using environmentally friendly techniques and solvents. In this study, the extraction of polyphenolic compounds from Cistus creticus is discussed. Extraction of the compounds has been carried out with water and ethanol, employing the most common approach. To further enhance the extraction yield, the usage of four deep eutectic solvents (DESs) has also been examined. In an effort to further enhance the extraction yield, pulsed electric fields have also been employed. According to the results, it was evident that the use of DESs made of glycerol: choline chloride (2:1) increased the extraction yield by 75%, compared to extraction with water. Moreover, the use of pulsed electric fields enhanced the extraction yield of the common approach, by up to 70%. When pulsed electric fields and DESs were combined, the extraction yield increased by 14%, compared to the use of DESs only. Finally, the extract was analyzed for its content in volatile compounds, and it was found that new compounds could be extracted with the use of DESs.