The effect of casein phosphopeptides (CPP) and ferrous bisglycinate (FebisGly) at different ratios (1:20, 1:10, and 1:5 w/w) on iron supplementation was investigated. The in vitro bioaccessibility, structural changes, antioxidant activity, and the effect of absorption inhibitors were also explored. The results demonstrated that CPP enhanced the bioaccessibility of FebisGly by 68.72 % ± 0.18 % and increased the β-sheet content from 21.60 % ± 0.23 % to 67.92 % ± 0.12 %, forming a stable secondary structure. The particle size distribution (PSD) and rheological analyses indicated that CPP significantly contributed to the formation of chelated irons, resulting in a uniform PSD and enhanced viscoelasticity. Moreover, it prolonged the gastric emptying time, reducing gastric irritation further. The carboxyl and amino groups in the CPP molecules participated in chelation reaction, improved the antioxidant activity, and competed with phytic acid, tannic acid, and cellulose for iron. Overall, these results laid a foundation for developing novel iron supplementation strategies.

中文翻译：

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CPP-febisgly 复合物的结构变化和体外生物可及性：对铁负荷的依赖性


研究了不同比例 （1：20、1：10 和 1：5 w/w） 的酪蛋白磷酸肽 （CPP） 和双甘氨酸亚铁 （FebisGly） 对补铁的影响。还探讨了体外生物可及性、结构变化、抗氧化活性和吸收抑制剂的作用。结果表明，CPP 将 FebisGly 的生物可利用性提高了 68.72 % ± 0.18 %，β片含量从 21.60 % ± 0.23 % 提高到 67.92 % ± 0.12 %，形成了稳定的二级结构。粒度分布 （PSD） 和流变学分析表明，CPP 显着促进了螯合铁的形成，从而产生了均匀的 PSD 和增强的粘弹性。此外，它延长了胃排空时间，进一步减少了胃刺激。CPP 分子中的羧基和氨基参与螯合反应，提高抗氧化活性，并与植酸、单宁酸和纤维素竞争铁。总体而言，这些结果为开发新的补铁策略奠定了基础。