In this paper, for the first time the binding behavior of cadmium (Cd²⁺) to rice proteins (RPs) was studied. The results showed that the equilibrium of binding was reached within 30 min at 303 K with a maximum binding amount (q) of 15.26 mg/g, and the pH was an important factor positively influencing q. At both 308 K and 313 K, the binding of Cd²⁺ to RPs belonged to spontaneous, endothermic interactions with high-affinity, assigned to a multidentate coordination. Except for acetate, all the investigated competing coordination agents, such as edetate, pyrophosphate and citrate, showed inhibitory effects on RPs-Cd²⁺ binding, and edetate seemed to be the most effective one. At pH 6.5, calcium, copper and zinc began to restrict RPs-Cd²⁺ binding when the metal ion concentration reached 500 mg/kg, and the decreasing of pH would strengthen the inhibitory effects of the investigated metal ions including ferric ions.

本文首次研究了镉（Cd ²⁺）与大米蛋白（RPs）的结合行为。结果表明，在303 K下30分钟内达到了结合平衡，最大结合量（q）为15.26 mg / g，pH是一个积极影响q的重要因素。在308 K和313 K处，Cd ²⁺与RP的结合属于具有高亲和力的自发吸热相互作用，并分配给多齿配位。除乙酸盐外，所有已研究的竞争性配伍剂，如乙二胺四乙酸盐，焦磷酸盐和柠檬酸盐，均对RPs-Cd ²⁺具有抑制作用。具有约束力的行为，并且进行食欲似乎是最有效的方法。在pH 6.5时，当金属离子浓度达到500 mg / kg时，钙，铜和锌开始限制RPs-Cd ^2+的结合，pH的降低将增强所研究的金属离子（包括三价铁离子）的抑制作用。