利用离子交换平衡法研究了茶褐素与金属离子的络合作用,探讨了pH和温度对络合稳定常数的影响。结果表明,茶褐素与Ca2＋和Zn2＋的络合稳定常数受pH影响,在pH=7.0时均最高;而升高温度不利于络合反应的进行;茶褐素与金属离子发生络合后其酸基含量减少,说明茶褐素中起主要络合作用的羧基和酚羟基等主要酸性基团与金属发生了络合作用。茶褐素与金属的络合作用为进一步研究茶褐素对人体的作用及其保健品的开发提供理论依据。%The cation-exchange equilibrium method was used to research the complexation of theabrownine with metal ions,and probes into the pH and temperature impact on complex stability constant.The results showed that the pH influncence the stability constants of theabrownine with Ca2＋and Zn2＋,and the stability constants was the highest when the pH was 7.0.While elevated temperature was adversed to the conduct of complex reaction.The acid-base content was reduced by the complex reaction,it was indcating that carboxyl and phenolic hydroxyl groups on theabrominen played a major role in the complexation to react with metal ions.The complexation of theabrownine with metal ions provided theoretical basis for further research of the human body and the development of health care products.
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