牡蛎低分子肽双重乳液体外模拟消化吸收特性研究

In vitro Simulated Digestion and Absorption Characteristics of Double Emulsion of Low Molecular Weight Oyster Peptides

摘要:

牡蛎低分子肽(low molecular weight oyster peptides,LOPs)具有多种生物活性,但是存在腥味及易于被胃肠消化液降解的缺陷,采用双重乳液包封LOPs可显著改善其腥味,然而其消化吸收特性相关研究较少。以LOPs为研究对象,分析其界面性质,采用W₁/O/W₂型双重乳液封装LOPs,利用体外模拟消化及单层Caco-2细胞模型研究LOPs的消化吸收特性。研究结果显示:LOPs具有较好的亲水性但不具有降低油水间界面张力的能力。在体外模拟消化过程中,LOPs双重乳液平均粒径由最初的(725.5±25.4)nm先增至(944.6±21.8)nm,最后降低为(772.8±21.4)nm；包封率由88.35%逐步降至30.01%；光学显微图像显示,乳液在胃消化模拟阶段出现了不同程度的聚集,并于肠道消化阶段出现破裂。单层Caco-2细胞模型的体外模拟吸收实验结果显示,LOPs的转运方式为被动扩散,而LOPs双重乳液的转运机制为外流效应。LOPs双重乳液能有效提高LOPs的生物利用率,对LOPs具有良好的保护与缓释作用。

Abstract:

Low molecular weight oyster peptides(LOPs)have various biological activities, but it has the defects of fishy odor and easy degradation by gastrointestinal digestive juices. It has found that the undesirable flavor of LOPs can be improved significantly by encapsulating with double emulsion, but the digestive and absorptive properties of LOPs encapsulated with double emulsion have not been sufficiently studied. Taking LOPs as the research object, interface properties were analyzed, W₁/O/W2 double emulsion was used to encapsulate LOPs, and the digestion and absorption characteristics of LOPs were studied by using in vitro simulated digestion and single-layer Caco-2 cell model. The results showed that LOPs had good hydrophilicity but couldn't reduce the interfacial tension between oil and water. During the simulated digestion process in vitro, the average particle size of LOPs double emulsion increased from initial (725.5±25.4) nm to (944.6±21.8)nm and finally decreased to (772.8±21.4)nm. The encapsulation rate decreased from 88.35% to 30.01%. Optical microscopic images showed that it had aggregation with different degrees at the stage of gastric digestion and ruptured at the stage of intestinal digestion. The results of single-layer Caco-2 cell model of in vitro simulated absorption experiments showed that the transport mode of LOPs was passive diffusion, while the transport mechanism of LOPs double emulsion was outflow effect. Double emulsion of LOPs could effectively improve the bioavailability of LOPs and provide good protection and slow-release effects on LOPs.