Optimization of water extraction and macroporous resin purification processes of flavonoids from Radix Puerariae

Objective To optimize the processes of water extraction and macroporous resin purification of flavonoids from Radix Pueraiae.Methods The orthogonal test was used to optimize the water extraction process and the monofactorial observation to optimize the macroporous resin purification process,with the extraction rates of puerarin and the total flavonoids as the indexes.Results The optimum water extraction process was as follows:9 times mount of water was used to extract pueraria for 3 times with 90 min each time.The extraction rate of the total flavonoids was 92.17%and that of puerarin,84.91%.The optimum macroporous resin purification process was as follows:macroporous resin HPD - 750 was used with the ratio of diameter to length as 1:6,the concentration of the sample solution was 1.5 g/mL,the maximum sample was 3 BV,the flowing rate was 1 mL/min,the eluant was 70%ethanol and the eluant volume was 5 BV.The extract yield was 4.47%after macroporous resin purification.The content of total flavonoids was 76.22%and that of puerarin,56.20%.Conclusion This optimum process is easy to operate,which can be applied in large - scale producution of the total flavonoids and puerarin.