Ultrasound and microwave-assisted extracting hesperidin form citrus and study of its antioxidant activities

In this paper, ultrasonic and microwave-assisted extraction methods were compared in order to determine the efficient extraction method, while evaluating the antioxidant activity of hesperidin extract.Single factor and orthogonal design were adopted in the experiments.1-year dried citrus peel was as raw materials and hesperidin was used as detection index, considering solid-liquid ratio, extraction time and extraction power to compare the two methods of extraction process.The results showed that the optimum process conditions of ultrasound-assisted extraction was solid-liquid ratio 1 : 50, ultrasonic time25 min, ultrasonic power 80 W and under this condition the extraction rate was 8.06% ± 0.02%. While optimum process conditions of microwave-assisted extraction was solid-liquid ratio 1 : 50, microwave time 40 s, microwave power 240 W and under this condition the extraction rate was 8.12% ± 0.04%.Compared with the ultrasound-assisted extraction, microwave-assisted extraction takes less time and exhibits more effcient extraction rate, so the method of microwave-assisted extraction was regarded as a more effective way.In addition, it was proved that hesperidin had certain scavenging effect on DPPH· and ·OH, and also had certain reduction effect on Fe3 +.