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 °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.