乳铁蛋白-EGCG共价复合物对鱼油乳液稳定性和消化特性的影响

通过碱处理法制备乳铁蛋白（lactoferrin，LF）-表没食子儿茶素没食子酸酯（epigallocatechin gallate，EGCG）共价复合物，研究LF-EGCG物理混合物和共价复合物对鱼油乳液流变性质、氧化稳定性和体外消化特性的影响。由于EGCG与LF共价结合，蛋白质分子质量增加，使得共价复合物制备的乳液黏度增加（其黏度分别是单一蛋白乳液和物理混合物乳液的2.74 倍和1.42 倍），物理稳定性显著增强（在55 ℃恒温、避光贮藏15 d后仍能保持较好的流动性）。与LF稳定的乳液相比，物理复合或共价结合的LF-EGCG能够有效地抑制贮藏过程中鱼油氧化（贮藏第15天时，LF、物理混合物和共价复合物稳定的鱼油乳液中脂质的硫代巴比妥酸反应物值分别为2.25、0.75 nmol/g和0.70 nmol/g）。在体外消化过程中，共价复合物稳定的鱼油乳液能够更好地抑制聚集体的产生，在一定程度上延缓脂肪酸的释放。本研究能够为合理设计鱼油递送系统提供一定参考。

Effect of Lactoferrin-Epigallocatechin Gallate Covalent Complex on the Stability and Digestion Characteristics of Fish Oil Emulsions

The effects of lactoferrin (LF)-epigallocatechin gallate (EGCG) covalent complex, prepared by alkaline treatment, and their physical mixture on the rheological properties, oxidative stability and in vitro digestion characteristics of fish oil emulsions were studied. As the molecular mass of LF increased after combining with EGCG, the emulsion viscosity was 2.74 and 1.42 times higher with the complex than with single LF or the physical mixture, respectively, and the complex remarkably enhanced the physical stability and maintained good fluidity of emulsions for 15 d at 55 ℃ consistently in the dark. The complex and the physical mixture were more effective at inhibiting fish oil oxidation than single LF; the thiobarbituric acid reactive substances (TBARS) values of lipids in fish oil emulsions stabilized by single LF, the physical mixture and the covalent complex were 2.25, 0.75 and 0.70 nmol/g, respectively on the 15th day of storage. During the in vitro digestion process, the covalent complex-stabilized fish oil emulsion showed better inhibition of aggregation and delayed release of fatty acids to some extent. This study provides a basis for the rational design of fish oil delivery systems.