杉树木质纤维素对酯型儿茶素类选择性吸附的研究

以杉木屑为原料制备木质纤维素,采用静态吸附、蒸馏水和80%乙醇分段洗脱等实验,研究其对茶儿茶素类及咖啡因选择性吸附作用.结果表明,木质纤维素对茶叶儿茶素没食子酸酯类(酯型儿茶素类)的吸附量明显大于咖啡因,经木质纤维素吸附后,大部分的咖啡因保留在溶液中,只有少量被木质纤维素吸附,达到初步脱咖啡因的效果;吸附的木质纤维素经水和80%乙醇分段洗脱,水洗脱液中咖啡因、酯型儿茶素类分别与儿茶素类总量的比例为0.08,0.36;而80%乙醇洗脱液中上述比例分别为0.02,1,通过分段洗脱可以进一步脱除咖啡因,得到脱咖啡因的高酯型儿茶素类产品.

Study on the specific adsorption of catechin gallates by cedar lignocellulose.

Lignocellulose was prepared from cedar sawdust and used to isolate caffeine and tea catechins from tea extract by static adsorption and gradient elution using water and 80% ethanol.The results showed that there were obvious different adsorption for tea caffeine and catechin gallates by the lignocellulose.The lignocellulose had stronger adsorption to catechin gallates than to caffeine.The lignocellulose column adsorbed tea extracts was washed by gradient elution using water and 80% ethanol,the ratios of caffeine and catechin gallates to total catechins were 0.08 and 0.36 in the water eluate,respectively,while the ratios were 0.02 and 1 in the eluate of 80% ethanol.This suggested that decaffeinated catechin gallates could be obtained by gradient washing the cedar lignocelulose which adsorbed tea extracts using water and 80% ethanol.