基于纳米豆粕的β-胡萝卜素营养载运体系构建

Here, nano defatted soybean was used as nutrition carrier for β-carotene delivery system. After nanofabrication, defatted soybean flour fell in nanosize, namely nano defatted soybean. The scale effect conferred the nano defatted soybean high adsorption capacity and strong aggregation tendency, which made it suitable for being the nanocarrier. .In presented proposal, three parts of work would be done. At first, an adsorption-aggregation way would be applied to construct the nano defatted soybean based β-carotene delivery system. Three aspects, the size of nano defatted soybean, the ratio of nano defatted soybean/β-carotene and constructing condition should be considered. After nano defatted soybean were adsorbed with β-carotene on the surface, they aggregated into nanoclusters, packaging these nutrition in among nanoparticles. The effect of particle size,carrier/nutrition ration would be investigated, and constructing conditions (in cluding the size of nano defatted soybean flour, ion concentration of the solution, pH value, temperature, stirring and so on) would be optimized..Secondly, the nutrition delivery system could be characterized on physical, chemical property. The carrying capacity, the amount of β-carotene that certain amount of nano defatted soybean can carry, would be quantified. And nutrition releasing dynamic would be characterized to find how much β-carotene would release from the delivery system depending on duration. The way nutrition binded in the cluster could be speculated from the detecting on its conformation, so spectroscopic methods would be applied to study the property of β-carotene..The stability and bioavailability of β-carotene are the third and most important subjects to be studied. The stability of β-carotene would be defined by its oxidation resistance. Study the DHHP cleaning ability of β-carotene in delivery system and its relationship with time duration comparing to normal β-carotene. The bioavailability of β-carotene is determined by its ability of penetrating through intestinal epithelial. The ability of penetrating through intestinal epithelial experiment would be performed in a culture Caco-2 cell model, measuring the concentration of β-carotene in one side of the cell layer after the β-carotene delivery system were put in the other side..Work in this project would explore the interaction between the nano food particle and nutrition, discover the regulation of nano food in nutrition delivery system as nanocarrier. This kind of delivery system can enhance the stability of nutrition and finally upgrade the bioavailability. This work would also offer a new instruction on development and application of nano food.

本研究拟利用纳米豆粕载运β-胡萝卜素，探索纳米食品对营养素的载运规律。纳米豆粕由豆粕经纳米加工获得，因其尺度效应而具有吸附性好、集聚性强的特点，适于作为营养素载体。研究主要包括：吸附-积聚法构建基于纳米豆粕的β-胡萝卜素载运体系，选用适宜粒径分布的纳米豆粕，优化纳米豆粕与β-胡萝卜素的配比和载运（积聚）条件，使得纳米豆粕在表面吸附β-胡萝卜素后发生积聚，将营养素包裹在积聚体中完成载运体系构建；对载运体系的形貌，载运能力、释放动态等物理化学性质进行表征；通过分析营养素的光谱学性质研究其与载体的结合方式；观察载运后β-胡萝卜素的抗氧化能力变化和小肠上皮穿透能力，考察载运后营养素的稳定性和生物利用率的变化。本项目研究探索纳米食品颗粒与营养素相互作用，揭示纳米食品营养载运体系的载运规律，可为营养素的载运提供新型载体，提高营养素的稳定性，实现营养素的高效利用，也为纳米食品的开发利用提示新的方向。

豆粕是大豆油加工榨油后的副产品，其低脂肪高蛋白，营养丰富，但没有得到较好的利用。纳米豆粕是将豆粕加工成纳米颗粒，由于它粒径小，比表面积大，能吸附大量营养物质，可以用于营养载运体系的构建。本研究首先对纳米豆粕的安全性进行了细胞学检测，CCK法证实各种粒径的豆粕对Caco-2细胞均无毒性。对纳米豆粕积聚特性的研究显示，纳米豆粕的积聚以及与营养素的结合，主要依靠氢键来实现，其载运过程受到pH值的影响最大。利用纳米豆粕分别构建了β-胡萝卜素载运体系和维生素B2/B6的混合载运体系并进行表征。在β-胡萝卜素载运体系中，纳米豆粕的载运效率较高，且载运后的β-胡萝卜素稳定性大幅提升。在维生素B2/B6的混合载运体系中，VB2的载运效率与混合溶液中VB2的浓度与纳米豆粕的浓度相关，而VB6载运效率不仅和自身浓度、豆粕浓度相关，还受到VB2的浓度的影响。载运后，VB2释放速度略低于游离维生素，而VB6的释放速率则显著降低。但在吸收方面，载运对两种维生素穿过Caco-2细胞层的速率均无明显影响。纳米豆粕载运能够实现部分营养素的稳定性提高，释放速度的降低，具有一定的实用价值。由于研究没有涉及到粒径较小的豆粕颗粒（100nm左右），故粒径对豆粕载运性质的影响还需更加深入的研究。