Studies on Total Flavonoids Extraction from Perilla using Ultrasonic-assisted Extraction

The extraction of total flavonoids from Perilla, using ultrasonic-assisted method, was investigated in this work. Various extraction conditions, such as ethanol concentraction (V/V), volume-weight ratio between the extraction solution and the weight of Perilla (V/W), the extraction time (t), pH, temperature (T), agent concentration (c) have been investigated for their influences. With the: help of orthogonal analysis, the optimum extraction conditions have been identified, an extraction rate of 0.97% could be achieved at an ethanol concentration of 60%, an extraction temperature of 50 degrees C, a volume-weight ratio of 30:1, an ultrasonication time of 50 min. Then 8 samples were screened under this optimal extraction condition, the extraction rate could be 1.71% when use the Perilla leave (production in Linan, Zhenjiang province) as raw material.