Abstract: The paper studied the extracting of flavonoids in loquat pit with microwave assisted extraction (MAE). The single factor and orthogonal design methods L9(34) were applied for the optimal technological conditions: m(ethanol)/m(loquat pit)=15, microwave power 296W and 3 times extracting with microwave for 120 seconds, and 50% ethanol. In these conditions, the yield of flavonoids is 1.41%. As compared with tradition ethanol extraction, the microwave extraction is a rapid method with higher yield. At the same time, a linear relationship exists between scavenging of hydroxyl radical and the extracting of flavonoids in loquat pit (R2=0.9865).

Key words: loquat pit, microwave assisted extraction (MAE), flavonoids, hydroxyl radical, scavenging