MICROWAVE-ASSISTED EXTRACTION OF PHENOLIC AND FLAVONOID COMPOUNDS FROM Eucalyptus camaldulensis Dehn LEAVES AS COMPARED WITH ULTRASOUND-ASSISTED EXTRACTION

Abstract In the present study, a microwaveassisted extraction (MAE) technique has been developed for extraction of phenolic and flavonoid compounds from eucalyptus leaves. Various experimental conditions, such as solvent type, ethanol concentration, MAE time, liquid/solid ratio and preleaching time before MAE were examined to optimize the extraction. Among the solvents tested, 50% aqueous ethanol extracted the highest phenolic and flavonoid contents from eucalyptus leaves. The extraction of phenolic and flavonoid compounds with MAE for 5 min was equivalent with ultrasoundassisted extraction (UAE) (60 min) and traditional extraction (24 h) methods. Time of extraction at room temperature and UAE was about 288 and 12 times higher than the needed with MAE, respectively. Due to the considerable saving in time, MAE was more effective than the traditional and UAE methods