牡蛎源肽锌纳米粒体外胃肠道消化稳定性及作用机制

本研究旨在探究体外模拟消化对牡蛎源肽锌纳米粒(OPH-Zn)稳定性及其结构的影响，揭示OPH-Zn在胃肠道消化过程中的动态变化规律。采用各种光谱仪(紫外、红外和荧光)、电镜(扫描和透射)以及粒度仪测定模拟消化液中OPH-Zn的锌含量、表面形貌、二级结构以及粒径分布变化。研究发现，OPH-Zn总锌含量高达228.89±2.53 mg/g；在模拟胃液消化过程中，OPH-Zn和ZnSO₄对照中可溶性锌含量变化不大，且两个样品无显著差异(P>0.05)；转为模拟肠液消化时，OPH-Zn和ZnSO₄的锌溶解性分别降低了28.07%和55.31%(P<0.05)，与ZnSO₄相比，OPH-Zn可溶性锌含量显著高于ZnSO₄(P<0.05)；光谱分析发现，OPH-Zn在模拟胃液和肠液中保持相对稳定，但在由胃液过渡到肠液时，Zn2+与肽键中氧原子和氮原子的配位作用发生变化，电镜结果显示不同消化程度的OPH-Zn表面微观结构和颗粒大小也存在一定差异。结果表明，OPH-Zn在模拟胃肠道消化中具有一定的...

Stability and Mechanism of Oyster Peptide Hydrolysate Zinc Nanoparticles during in Vitro Gastrointestinal Digestion

The aim of this study was to investigate the effects of in vitro simulated digestion on the stability and structure of oyster protein hydrolysate zinc nanoparticles (OPH-Zn), and to reveal the dynamic variation rule of OPH-Zn under different degrees of gastrointestinal digestion. Atomic absorption spectrophotometer, UV scanner, infrared spectrometer, fluorescence spectrometer, scanning electron microscope, transmission electron microscope and particle size analyzer were used to determine the zinc content, surface morphology, secondary structure and molecular weight distribution of OPH-Zn in digestive fluid in simulated gastrointestinal digestion process. The results showed that the total zinc content of OPH-Zn was 228.89±2.53 mg/g. During simulated gastric digestion, soluble zinc content in OPH-Zn and ZnSO₄ controls remained stable basically, and there was no significant difference between the two samples (P>0.05). When the digestion was transferred from the stomach to the intestine, the zinc solubility of OPH-Zn and ZnSO₄ decreased by 28.07% and 55.31% (P<0.05), respectively. The soluble zinc content of OPH-Zn was significantly higher than that of ZnSO₄ during the whole intestinal digestion (P<0.05). The spectral analysis showed that OPH-Zn remained relatively stable in simulated gastric juice and intestinal juice, but the coordination between the oxygen and nitrogen atoms of peptide bond and Zn2+ was changed during the transition from gastric juice to intestinal juice. The results of electron microscopy showed that the surface microstructure and particle size of OPH-Zn were different with different levels of digestion. The results revealed that the OPH-Zn had a certain stability in simulating gastrointestinal digestion and was a potential zinc supplement with commercial potential. At the same time, the structural changes of OPH-Zn would also provide a certain research basis for the development and follow-up study of peptide-zinc nanoparticles.