Comparison of Two Extraction Methods of Flavonoids from Propolis

[Objective] The research aimed to provide basis for further development and utilization of propolis resources.[Method] Using orthogonal test,the process conditions and efficiency of flavonoids extraction from propolis by ethanol extraction method and microwave-assisted method were compared.[Result] The best optimum process conditions of extracting flavonoids from propolis by ethanol extraction method were as follows:solid-to-liquid ratio of 1∶ 30,extracting temperature of 60 ℃,extraction time of 6 h and ethanol concentration of 70%.Under these conditions,the extraction ratio of flavonoids was 9.931%.The optimum process conditions of extracting flavonoids from propolis by microwave-assisted extraction were as follows:solid-to-liquid ratio of 1∶ 50,microwave power of 420 W,microwave treatment time of 40 s and ethanol concentration of 70%.Under these conditions,the extraction ratio of flavonoids was 14.574%.[Conclusion] Microwave method is rapid and efficient,so it can be used as an ideal extraction method of flavonoids from propolis.