共存抗坏血酸下明胶对花色苷稳定性的影响及机理研究  

Effect of Gelatin on the Stability of Cyanidin-3-O-glucoside in the Presence of Ascorbic Acid and Its Mechanism

作　　者：马静 李丽[1] 由耀辉 冯治平[1] MA Jing;LI Li;YOU Yaohui;FENG Zhiping(College of Bioengineering,Sichuan University of Science and Engineering,Yibin 644000,China;Special Agricultural Resources in Tuojiang River Basin Sharing and Service Platform of Sichuan Province,Neijiang Normal University,Neijiang 641000,China;Key Laboratory of Fruit Waste Treatment and Resource Recycling of the Sichuan Provincial College,Neijiang Normal University,Neijiang 641000,China)

机构地区：[1]四川轻化工大学生物工程学院,四川宜宾644000 [2]内江师范学院沱江流域特色农业资源四川省科技资源共享服务平台,四川内江641000 [3]内江师范学院果类废弃物资源化四川省高等学校重点实验室,四川内江641000

出　　处：《食品工业科技》2023年第17期84-90,共7页Science and Technology of Food Industry

基　　金：四川省重点研发项目(20ZDYF1838);内江市科技计划项目(2020KJJH003,NJK21-001);四川轻化工大学大学生创新创业训练计划项目(S202010622071)。

摘　　要：花色苷是果汁饮料中主要的呈色物质,然而,其稳定性差,特别是在抗坏血酸(Vitamin C,V_(C))存在下极易降解褪色,严重影响果汁饮料的品质。为探究V_(C)存在下花色苷的稳定性,本文以矢车菊-3-O-葡萄糖苷(Cyanidin-3-O-glucoside,C3G)-V_(C)模拟体系为对象,研究贮存过程中明胶对C3G稳定性的影响,并通过荧光光谱、分子对接等手段对明胶与V_(C)及明胶与C3G之间的相互作用进行研究并揭示相关机理,同时,也考察了在无V_(C)的模拟体系中明胶对C3G稳定性的影响。结果表明,共存V_(C)下明胶能显著提高C3G的稳定性,当体系中明胶质量浓度为0.5 g/L时,C3G的半衰期由121 h延长至191 h,而无V_C存在下明胶不能提高C3G的稳定性。荧光分析表明,C3G和V_(C)均对明胶有较强的荧光猝灭作用,猝灭机制都为静态猝灭,且C3G与明胶的结合常数远大于V_(C)与明胶的结合常数(10^(5)vs 10^(4)),这表明三者共存时明胶将优先与C3G结合。另外,分子对接也证实了C3G与明胶的结合能力强于V_(C)与明胶的结合能力,且两者与明胶的作用力都主要是通过氢键及疏水作用。因此,推测明胶与V_(C)竞争结合C3G形成复合物,降低了V_(C)对C3G的可及性,从而提高了C3G稳定性。Anthocyanins are the main color substances in fruit juice beverages.However,they are susceptible to degradation and fading,particularly in the presence of ascorbic acid(VC),which harms the quality of fruit juice beverages.In this study,the cyanidin-3-O-glucoside(C3G)-VC simulation system was used to examine the effect of gelatin on the stability of C3G during storage.The interactions between gelatin and VC,gelatin and C3G were investigated,and the corresponding mechanisms were elucidated using fluorescence spectra and molecular docking.Additionally,the effect of gelatin on the stability of C3G in the simulation system without VC was also examined.The results demonstrated that gelatin could significantly improve the stability of C3G under coexisting VC,as the half-life of C3G increased from 121 h to 191 h when the mass concentration of gelatin in the system was 0.5 g/L.However,gelatin could not improve the stability of C3G in the absence of VC.Fluorescence measurements demonstrated that both C3G and VC could effectively quench the intrinsic fluorescence of gelatin via static quenching.Moreover,the binding constants between C3G and gelatin were significantly greater than those between VC and gelatin(105 vs 104),indicating that gelatin would preferentially bind to C3G in the presence of all three.In addition,molecular docking also confirmed that the interaction between C3G and gelatin was stronger than the interaction between VC and gelatin,and the interaction forces were proved to be hydrogen bonding and hydrophobic interactions.Therefore,it is hypothesized that gelatin competes with VC to bind C3G and form a complex,reducing the accessibility of VC to C3G and enhancing the stability of C3G.

关 键 词：花色苷 明胶 降解动力学 荧光光谱 分子对接 相互作用 

分 类 号：TS201.2[轻工技术与工程—食品科学]