沙棘籽粕膳食纤维的结构特征与功能性质分析

Analysis of Structural Characteristics and Functional Properties of Dietary Fiber from Seabuckthorn (Hippophae rhamnoides L.) Seed Meal

摘要:

为探讨沙棘籽粕膳食纤维的理化功能性质。该研究以沙棘籽粕为原料，采用复合酶解法制备得到沙棘籽粕的可溶性膳食纤维（Soluble Dietary Fiber, SDF）和不可溶性膳食纤维（Insoluble Dietary Fiber, IDF），并进行了系统表征其理化性质及结构特征。结果显示，IDF得率为76.03%，占主导地位，SDF得率仅为5.23%。在化学成分方面，SDF中总糖含量高达84.43%，显著高于IDF，而两者黄酮类化合物含量无显著差异；在结构特征方面，红外光谱分析显示SDF与IDF化学组成相似，但SDF氢键网络更紧密；X-射线衍射分析了SDF的无定型结构以及IDF的有序高结晶度。扫描电镜观察显示，SDF为平滑均匀球状，而IDF为大块多孔蜂窝状。功能特性分析表明，IDF因其粗糙多褶皱表面及多孔网状结构，展现出优异的持水能力（2.50 g/g）、持油能力（2.96 g/g）及膨胀性能（3.66 mL/g），SDF则因少结晶和松散结构，展现出优异的水结合力（1.86 g/g）。此外，两种组分均表现出潜在的胆固醇吸附作用和葡萄糖吸附能力。该研究不仅为沙棘籽粕的高值化利用提供了新途径，也为膳食纤维的深入研究和应用开发提供了科学依据。

Abstract:

To investigate the physicochemical and functional properties of dietary fiber from sea buckthorn (Hippophae rhamnoides L.) seed meal, seabuckthorn seed meal was used as the raw material, and the soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) were prepared via composite enzymatic hydrolysis. Their physicochemical properties and structural characteristics were systematically characterized. The results showed that the IDF yield was 76.03%, which was dominant, and the yield of SDF was only 5.23%. In terms of chemical composition, SDF had a total sugar content of 84.43%, which was significantly higher than that of IDF, while there was no significant difference in the content of flavonoids between the two. In terms of structural characteristics, infrared spectroscopy analysis revealed that SDF and IDF had similar chemical compositions, but SDF had a denser hydrogen-bond network. X-ray diffraction patterns further revealed the amorphous structure of SDF and the ordered structure and high crystallinity of IDF. Scanning electron microscopy showed that SDF appeared as smooth, uniform and spherical particles whilst IDF occurred as porous honeycomb structures. Functional property analysis showed that IDF outperformed SDF in water-holding (2.50 g/g), oil-holding (2.96 g/g), and swelling (3.66 mL/g) capacities, due to IDF’s rough and wrinkled surface and porous network structure. SDF exhibited superior water-binding capacity (1.86 g/g) due to its loose and low-crystallinity structure. In addition, both fractions demonstrated potential cholesterol adsorption and glucose retardation capabilities. This study not only provides a novel strategy for g high-value utilization of sea buckthorn seed meal, but also offers a scientific basis for in-depth research, application and development of dietary fiber.