Comprehensive Evaluation on Pretreatment Methods of Propolis by Determination of Total Flavonoids, Galangin and Chrysin Content

OBJECTIVE To establish optimal propolis pretreatment methods by comprehensive evaluation. METHODS Single-factor and orthogonal experiment was designed with the content change of total flavonoids, galangin and chrysin as evaluation index to screen the best pretreatment methods. RESULTS The optimal pretreatment condition was as follows: 95% ethanol was used as extraction solvent, ultrasonic extraction was applied at 50 ℃ for 2 times, 30 minutes for each time. CONCLUSION The method was scientific and reasonable which can be used in pretreatment of propolis.