茶黄素（TFs）是红茶中重要的品质成分和活性成分，具有抗氧化、调节人体糖脂代谢等多种生物活性。但是，TFs在生物体内的吸收利用率低，导致其生物利用度不高。本项目拟从化学屏障、消化酶屏障、粘液屏障、肠上皮细胞屏障四个方面开展TFs消化吸收机制的研究，利用消化吸收屏障模型、荧光标记、分子对接和SPR等技术，探明TFs在消化吸收过程中的变化规律及限制其消化吸收的关键环节，并揭示小肠上皮细胞对TFs的摄取、转运、定位机制；选取食源性壁材，采用乙醇注入法构建以大豆卵磷脂和胆固醇为主要壁材、壳聚糖和三聚磷酸钠为修饰壁材的TFs纳米脂质体，以包封率为指标探索最佳壁材浓度，最大程度保证TFs的包埋效果，并评价TFs纳米脂质体的消化稳定性和吸收率；采用大鼠口服实验，通过评价TFs的代谢动力学和组织分布特点揭示TFs的释放规律。本项目的实施将为提高TFs的生物利用度、实现TFs的高效利用提供理论依据。

Theaflavins (TFs), the main bioactive compound in black tea, are reported to show a variety of health functions such as antioxidant, glucolipid metabolism regulation. However, the low absorption rate severely limits the bioavailability of TFs and the added value of black tea. With the employment of absorption barriers model, fluorescent labeling, molecular docking and many other techniques, the influence of the chemical barrier, enzymatic barrier, mucus barrier and intestinal epithelium barrier on TFs will be figured out, the mechanism of TFs uptake, transport and localization by small intestinal epithelial cells will be revealed, the interaction pattern between TFs and major digestive enzymes/absorption transporters will be clarified, and the key factors affecting TFs absorption will be identified. Then, different concentrations of soybean lecithin, cholesterol, chitosan, tripolyphosphate will be used to design TFs nanocarriers. Comparison of in-vivo stability among these nanocarriers will be conduct to choose the best nanocarrier, whose distribution characteristics will be evaluated. This research will lay a theoretical foundation for the bioavailability improvement, depth development and efficient utilization of TFs.