大孔吸附树脂对苜蓿皂苷的吸附和解吸附作用(英文)

Adsorption and Desorption of Alfalfa (Medicago sativa L.) Saponins by Macroporous Resin

采用5种不同极性的树脂（AB-8、S-8、NKA-9、D-101和X-5）来评价对苜蓿皂苷的吸附和解吸附作用,其中中等极性的AB-8树脂对苜蓿皂苷具有最大的吸附量,用55%~65%的乙醇溶液能有效地将吸附的皂苷洗脱下来。当苜蓿粗提物量和AB-8树脂量为1∶1时,树脂的吸附量达到饱和。采用AB-8树脂,用90%乙醇洗脱,苜蓿提取物的最大解吸附量为108.4 mg/g干重树脂。通过大孔树脂吸附和解吸附,将90%乙醇洗脱液浓缩,皂苷含量（53%）是苜蓿粗提物含量（5.68%）的9倍。结果表明,AB-8大孔吸附树脂可用于苜蓿皂苷的大规模制备。

Five types of macroporous adsorption resins namely AB-8,S-8,NKA-9,D-101 and X-5 with varying polarity were evaluated for the adsorption and desorption of alfalfa saponins.Of these,the moderately polar AB-8 resin showed the highest adsorption capacity and the absorbed saponins could be eluted effectively with 55-65% aqueous ethanol.The adsorption reached saturation at 1∶1 alfalfa extract to AB-8 resin mass ratio.The maximum desorption capacity of alfalfa extract was 108.4 mg/g dw AB-8 resin on a column eluted by 90% aqueous ethanol.The saponin content in the concentrated 90% aqueous ethanol effluent reached 53%,about 9 times of that（5.68%） in the crude alfalfa extract.The AB-8 macroporous resin has may be a favorable sorbent for large-scale saponin isolation from alfalfa.