鲷鱼鳞多肽-木糖美拉德反应产物的制备、结构与功能

探索反应时间、木糖(xylose,Xyl)与鲷鱼鳞多肽(fish scale peptides,FSP)质量比、Xyl与FSP总质量浓度、初始p H值和反应温度对Xyl与FSP美拉德反应的影响,并对在Xyl与FSP质量比1.3∶1、Xyl与FSP总质量浓度78 mg/m L、初始pH 11.85、反应温度100℃、反应时间4.05 h工艺条件下所得产物进行表征。荧光光谱、红外光谱、游离氨基含量以及N-三(羟甲基)甲基甘氨酸-十二烷基硫酸钠-聚丙烯酰胺凝胶电泳过碘酸Schiff碱染色等结构分析,表明FSP与Xyl经美拉德反应后发生共价交联,肽链结构发生变化且形成了新的化合物;1,1-二苯基-2-三硝基苯肼自由基、2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐自由基、羟自由基以及还原力测定表明,FSP经美拉德反应后抗氧化活性显著增加(P0.05);多酚氧化酶活性测定及苹果褐变实验表明,鲷鱼鳞多肽美拉德反应产物(FSP-MRPs)具有多酚氧化酶抑制活性,其IC_(50)值为0.54 mg/m L,其可能机理为FSP-MRPs具有Cu2+螯合特性,其螯合位点与抗氧化基团密切相关。

Preparation,Structure and Biological Activities of Maillard Reaction Products Derived from Snapper Fish Scale Peptides and Xylose

The purpose of this study was to investigate the Maillard reaction between snapper fish scale peptides (FSP) and xylose (Xyl) as a function of reaction time, mass ratio of Xyl to FSP, total concentration of Xyl and FSP, initial pH and temperature and to characterize the structure and properties of Maillard reaction products prepared from a mixture of Xyl and FSP (1.3:1, total concentration of 78 mg/mL, at initial pH 11.85) at 100 ℃ for 4.05 h. The changes in fluorescent intensity, Fourier transform infrared spectra, free amino group content and Tricine-SDS-PAGE with periodic acid Schiff staining suggested that covalent crosslinking between FSP and Xyl occurred, the structure of FSP was changed and new compounds were formed through Maillard reaction. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt radical (ABTS+·) scavenging, hydroxyl radical scavenging and reducing power assays suggested that the antioxidant activity of FSP was significantly improved via Maillard reaction (P < 0.05). The Maillard reaction products inhibited polyphenol oxidase activity with IC50 value of 0.54 mg/mL. The underlying mechanism may be attributed to their Cu2+-chelating activity and the chelating sites may be related to antioxidant groups.