Optimization of ultrasonic and microwave combined extraction of Lilium polysaccharide

To study the extraction proscess of Lilium polysaccharides, using Lilium produced in Pingliang, Gansu Province as the raw material, ultrasonic, microwave, and ultrasonic combined with microwave extraction approaches are employed to extract polysaccharides from Lilium. A single-factor test is conducted to investigate the impact of extraction conditions on the polysaccharide content and to compare the extraction rates of polysaccharide extracted by different extraction methods. The orthogonal experiment method and response surface method are utilized to optimize the extraction process. The results show that the ultrasonic method combined with microwave extraction yields a higher polysaccharide content, with an extraction rate of 19.37%. Microwave power and ultrasonic power are the primary factors influencing the extraction rate of polysaccharide. With the extraction rate of polysaccharide as the response value, the optimized extraction process is as follows: when the microwave power is 600 W, the microwave irradiation time is 25 min, the microwave irradiation temperature is 55 ℃, the ultrasonic power is 480 W, the ultrasonic time is 45 min, and the solid-liquid ratio is 1∶25 g·mL−1, the yield of Lilium polysaccharide is 23.94%, which is not significantly different from the predicted value (25.03%). Compared to other extraction methods, this approach has a high extraction rate, simple operation, and research value.