Separation and purification of Arabinogalactan obtained from Larix gmelinii by macroporous resin adsorption

Arabinogalactan (AG) obtained from Larix gmelinii R. was purified with the method of macroporous resin adsorption. Effects of various parameters on the adsorption, including adsorption time and temperature, the concentration and the dosage of raw AG, the reused numbers of resin, were investigated. The effect of purification was tested through the removal rate of impurity and the contents of AG and impurity. The optimal condition was determined as follows: adsorbed at 30°C for 2 h with the concentration of raw AG <0.1 g·mL−1 and its dosage < 7 mL, the dose of resin was 3 g and reused for 4 times. On the basis of these, macroporous resin column was used for AG purification. The result showed that the AG yield could reach 68.28% with sugar content of 95.02%. The analysis of IR and UV showed that the effect of macroporous resin characteristics on the purification of AG was significant. The obtained product had the same functional groups with standard sample.