柚皮蛋白-茶多酚纳米颗粒在Caco-2单层细胞模型中的转运机制及其应用

Pomelo Peel Protein-tea Polyphenol Nanoparticle Applications and Elucidation of Their Transport Mechanism in a Caco-2 Cell Monolayer Model

摘要:

为了探究柚皮蛋白-茶多酚纳米颗粒（PP-TPNs）在生物体内的吸收率及其在食品领域的应用潜力，该研究采用Caco-2细胞单层模型评估PP-TPNs对细胞存活率、跨上皮电阻值及碱性磷酸酶活性的影响，并将PP-TPNs添加到双柚汁、碳酸饮料和牛乳中，通过测定色差和多酚保留率来确定其在饮料中的适用性。该实验结果显示，在质量浓度为400 μg/mL时，空载颗粒和PP-TPNs均表现出良好的生物相容性，细胞存活率分别为88.83%和84.27%；PP-TPNs在Caco-2细胞单层模型上的单向转移率分别为41.72%和32.91%，双向转运系数为1.60。应用实验结果显示，4 ℃储藏30 d后PP-TPNs双柚饮料和PP-TPNs碳酸饮料中多酚保留率分别为82.42%和79.62%；95 ℃加热1 h后PP-TPNs蛋白饮料中多酚保留率在91.89%。该研究结论为PP-TPNs在小肠中易被吸收，吸收方式以主动运输为主；PP-TPNs在高温、光照等不利环境下仍能在饮料中稳定存在，这为深入研究PP-TPNs在肠道中的吸收机制提供了基础，并为相关应用研究指明方向。

Abstract:

To explore the absorption efficiency of pomelo peel protein-tea polyphenol nanoparticles (PP-TPNs) in vivo and elucidate potential food industry applications, the effects of PP-TPNs on cell viability, transepithelial electrical resistance, and alkaline phosphatase activity were evaluated using a Caco-2 cell monolayer model. PP-TPNs were also added to pomelo juice, carbonated beverages, and milk to determine their impacts on beverages by measuring color differences and polyphenol retention rates. At 400 μg/mL, unloaded nanoparticles and PP-TPNs both exhibit good biocompatibility, and respective cell viability rates are 88.83% and 84.27%. The respective unidirectional transport rates of PP-TPNs across a Caco-2 cell monolayer are 41.72% and 32.91%, and the bidirectional transport coefficient is 1.60. Application experiments indicate that after storage at 4 ℃ for 30 days, the respective polyphenol retention rates in pomelo juice and carbonated beverages with added PP-TPN are 82.42% and 79.62%. After heating at 95 ℃ for 1 h, the polyphenol retention rate in protein beverages with PP-TPNs remains at 91.89%. These studies indicate that PP-TPNs can easily be absorbed in the small intestine, primarily through active transport. PP-TPNs can also remain stable in beverages under adverse conditions such as high temperatures and light exposure. These findings provide a basis for further research on the absorption mechanism of PP-TPNs in the gut and offer insights to guide related application research.