Abstract:

To screen an optimal adsorbent for the purification of soybean saponins from low-temperature defatted soybean meal, four types of macroporous resin were compared for the differences in dynamic and static adsorption and desorption performances. AB-8-type macroporous resin was shown to have optimal adsorption and desorption capacities towards soybean saponins. The optimal desorption parameters for the purification of soybean saponins using AB-8-type macroporous resin were investigated, and the structure of purified soybean saponins was characterized by infrared (IR) spectroscopy. Results showed that the optimal elution of soybean saponins from AB-8-type macroporous resin was achieved by washing the resin with 2 BV deionized water followed by eluting with 70% ethanol at a flow rate of 0.5 BV/h. The eluate was concentrated by reduced pressure distillation and vacuum freeze dried and purified soybean saponins with 87.07% purity and 1.19% yield were obtained. In addition, the structure of purified product was confirmed by IR spectroscopy to be consistent with the known structure of soybean saponins.

Key words: soybean saponins, macroporous resin, purification, structural characterization