Study on the Extraction and Enrichment Technology of Total Flavonoids from Lespedeza bicolor

[Objective] The purpose was to study the optimum extraction technology and enrichment parameter for flavonoid from Lespedeza bicolor.[Method] L.bicolor distributed in Inner Mongolia Autonomous Region was selected to study the effects of ethanol concon.,ratio of liquid to solid,extraction time and temperature on the extraction rate of total flavonoids through single factor test and confirm the optimum extraction theology for total flavonoids through the orthogonal experiment of L16(44).The flavonoid was purified and enriched by SP700 macroporous adsorption resin to confirm the optimum enrichment parameter for flavonoid through the orthogonal experiment of L9(33).[Result] The flavonoid content in the leaves of L.bicolor was higher than that in the stem.The effect of the factors on the extraction rate of the flavonoid in order was ethanol concon. ratio of liquid to solid extraction temperature extraction time.The optimum extraction technology for flavonoid was follows: 40% alcohol,extraction temperature of 70 ℃,ratio of liquid to solid of 1∶30,extraction time of 3.0 h and the obtained flavonoid yield of 5.228%.The optimum enrichment parameter for flavonoid was follows: the sample injection rate of 1.5 ml/min and washing by 80% ethanol with the washing velocity of 2.0 ml/min.[Conclusion] This study provided the reference basis for further development of L.bicolor resource.