紫薯蛋白-葡萄糖美拉德产物制备及其与花色苷相互作用研究
Study on Preparation of Purple Sweet Potato Protein-Glucose Maillard Reaction Product and Its Interaction with Anthocyanin
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摘要: 通过干法美拉德反应制备紫薯蛋白-葡萄糖美拉德产物,并分析其与花色苷相互作用。采用聚丙烯酰胺凝胶电泳(SDS-PAGE)测定产物的分子质量,运用傅里叶红外变换光谱(FIRT)、差示扫描量热(DSC)和荧光光谱等多种方法对产物进行结构表征。结果表明:美拉德反应主要产物分子量为25 kDa;相较于紫薯蛋白花色苷复合物,美拉德产物的红外吸收强度普遍较低,尤其体现于酰胺I带处的红外吸收,美拉德产物变性峰温度(76℃)较高,变性焓值(366.7 J/g)较低;美拉德产物的最大荧光发射波长为340 nm,花色苷猝灭美拉德产物荧光为动静态联合猝灭,静态猝灭为主导;花色苷与美拉德产物之间的相互作用力属于强作用力,包括范德华力和氢键。花色苷与紫薯蛋白-葡萄糖美拉德产物相互作用结合位点靠近色氨酸残基。Abstract: The Maillard reaction product was successfully prepared and its interaction with anthocyanin was analyzed.The molecular weight of the product was determined by SDS-PAGE.The structural characteristic of the Maillard reaction product was characterized by FTIR,DSC and fluorescence spectrometric method.The results showed that the molecular weight of the main Maillard reaction product was 25 kDa.Compared with purple sweet potato protein-anthocyanin complexes,the FTIR absorption strength of Maillard reaction product was generally lower,especially in the amido I band,and maillard reaction product had higher denatured peak temperature(76℃),but its denaturation enthalpy(366.7 J/g)was lower.The maximum emission wavelength of the Maillard reaction product was 340 nm,and the results showed that purple sweet potato athocyanin quenched the fluorescence of Maillard reaction product via a combination quenching which had the features of the static and dynamic quenching,and static quenching was the main process.There was a strong force of interaction between anthocyanin and Mailard reaction product.The interaction was mainly expressed as van del Waals force and hydrogen bond force.The binding site between purple sweet potato anthocyanin and the Maillard reaction product was closer to tryptophan residue.