Microwave-assisted Extraction of Tyrosinase Inhibitor from Paeonia suffruticosa

The microwave-assisted extraction(MAE)technology of tyrosinase inhibitor from Paeonia suffruticosa was studied with the yield and the relative inhibitory ratio to tyrosinase(RIRT) of the extract as evaluating indexes.The optimal technological conditions were obtained as follows.Paeonia suffruticosa was crushed to 0.45 mm and extracted twice(each time 6 min) using 70% ethanol as extractant(mass ratio of ethanol to Paeonia suffruticosa 8 ∶1) with the cooperation of microwave(microwave power 450 W).After the extracted liquor was decoloured with activated carbon,concentrated under vacuum,and then dried under vacuum,dry extract of Paeonia suffruticosa was obtained in 22.8 % yield and the RIRT was 82.8 %.Compared with direct-heating extraction(DHE),MAE can shorten the extraction time from 90 min to 6 min,improve the yield from 19.7% to 22.8%,and RIRT from 77.2% to 82.8%.