花青素对大豆分离蛋白结构影响及其复合物抗炎能力

Effects of Anthocyanins on the Structure of Soybean Protein and Anti-Inflammatory Activity of Their Complex

研究不同质量浓度花青素与大豆分离蛋白在碱性条件(pH 9.0)下的共价复合,通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)、荧光光谱、圆二色光谱对复合产物的结构进行分析,并建立以脂多糖诱导的Raw264.7炎症细胞模型探究大豆分离蛋白对花青素抗炎能力的影响。结果表明,花青素质量浓度升高会导致大豆分离蛋白溶解度降低,主要猝灭机制为静态猝灭,二级结构中α-螺旋含量逐渐降低,β-折叠与无规则卷曲含量逐渐增加。当花青素质量浓度为1.000 mg/mL可通过SDS-PAGE观察到超大分子质量亚基的生成。大豆分离蛋白-花青素复合物剂量为200μg/mL时,当复合物体系花青素的添加质量浓度大于0.167 mg/mL,可以明显降低细胞分泌肿瘤坏死因子TNF-α以及NO的浓度。

In this paper, the covalent cross-linking at an alkaline pH （pH 9.0） between different concentrations of anthocyanins and soybean protein isolate （SPI） was studied. The structure of the products was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, fiuorescence spectroscopy and circular dichroism （CD） spectroscopy, and their inhibitory effect on lipopolysaccharide （LPS）-induced inflammation in RAW264.7 cell line was assessed. Results showed that the solubility of SPI decreased in the presence of increasing concentrations of anthocyanins and the quenching mechanism was a static process, showing a decrease in α-helix and an increase in β-sheet and random coil. The formation of super-macromolecular subunits was observed by SDS-PAGE in the presence of anthocyanins at 1.000 mg/mL. Besides, the addition of 0.167 mg/mL of the complex formed between SPI and anthocyanins at 200 μg/mL could markedly reduce the secretion of TNF-α and nitrite oxide （NO）.