沉淀-吸附法制备高纯酯型儿茶素
来源期刊：中南大学学报(自然科学版)2002年第3期
论文作者：唐课文 周春山 蒋新宇
文章页码：247 - 249
关键词：沉淀-吸附法;儿茶素;聚酰胺树脂;提取
Key words：precipitation-adsorption method; ester catechines; polyamide; preparation
摘 要：用ZnCl2作沉淀剂,当溶液pH值为5·6~6·5时,将茶叶浸提液中的儿茶素以金属盐的形式沉淀,沉淀物经洗涤后,用质量分数为40%的硫酸溶解,然后将溶液直接加入聚酰胺树脂柱上,先用蒸馏水将Zn2+,Na+等无机离子除去,再用乙醇将茶多酚洗脱,洗脱液经浓缩、干燥,得到纯度高于99%的高纯酯型儿茶素,提取率达10.2%,其中EGCG,GCG,ECG含量分别为64%,16%和19%,金属离子含量小于1×10-3%,未检出咖啡因.
Abstract: Catechines in tea were precipitated in the form of metallic salts with ZnCl2 as precipitant at pH 5.6-6.5.Then, the catech in is dissolved by 40% sulfuric acid solution (mass fraction) after being washed by water, and through the polyamide column. The inorganic ions such as Zn2+, Na+ were removed by distilled water, catechines were washed with 95% alcohol, after being condensed and dried, highly pure ester catechines were obtained. The effective ingredient of the ester catechines reached 99% with 10.2% extraction rate. The contents of EGCG, GCG, ECG are 64%, 16%and 19%, respectively. The content of metal ions in catechin was less than 10-3% and caffeine was not detected.
