基于甘蔗酚酸内源因子非酶褐变生色机制研究

Phenolic compounds have been implicated to be involved in colour formation of cane juice. One of the main factors contributing to the formation of colored compounds during sugar processing is the result of enzymatic or non-enzymatic reactions of polyphenols.The main research objects of this subject are phenolic acids and their derivatives in sugarcane. Phenolic compounds are separated and purified by Polyamide, Sephadex LH-20,and Preparative reversed-phase HPLC chromatography. The molecular structures are determined by UV,ESI/MS and comprehensive 1D (1H and 13C) and 2D (gradient multiple quantum filtered 1H-1H COSY, 1H-13C HSQC and 1H-13C HMBC)NMR analyses; In addition, polymerization reactions of phenolic acids and other compounds involved in the coupled oxidation process are reserached to analyze the formation of intermediate and advanced products,to explore several pathways related to phenols,and to futher elucidate the mechamise of non-enzymic browning of phenolic acids in sugarcane. This research will contribute to a comprehensive understanding of the change in colour caused by phenolic compounds during sugar processing, and also have important values in theoretical study and practical application of the Non-Enzymatic browning in fruits and vegetables.

甘蔗中多酚化合物对蔗汁色值影响极大，通过酶或化学作用形成的酚类色素是糖汁色值加深的主要因素之一。本项目拟以甘蔗酚酸及其衍生物为主要研究对象，运用聚酰胺、Sephadex LH-20凝胶色谱和制备RP-HPLC液相色谱等分离手段，以及质谱、一维、二维核磁共振波谱等分析技术，对甘蔗进行系统的多酚成分分离与结构鉴定；结合成分分析，研究酚酸及其衍生物在氧化缩合反应或与其它化合物共呈色反应过程的中间产物变化规律，探讨其非酶褐变的反应历程，阐明酚酸非酶褐变成色机制。项目的研究成果有助于理解多酚成分引起制糖过程色素变化的本质问题，为制糖工艺的技术改进提供理论基础及应用价值，同时在果蔬制品加工过程多酚非酶色素的生成及变化方面，也具有重要的学术价值及研究意义。

甘蔗中多酚化合物对蔗汁色值影响极大，通过酶或化学作用形成的酚类色素是糖汁色值加深的主要因素之一。本项目以甘蔗酚酸及其衍生物为主要研究对象，运用聚酰胺、Sephadex LH-20凝胶色谱和制备RP-HPLC液相色谱等分离手段，以及质谱、一维、二维核磁共振波谱等分析技术，对甘蔗进行系统的多酚成分分离与结构鉴定，分别鉴定了：4',5,7-三羟基-3',5'-二甲氧基异黄酮；threo-syringoylglycerol；没食子酸；(+)-pinoresinol；丁香醛；2-甲氧基-5-羟基桂皮酸甲酯；6-羟基-7-甲氧基香豆素；pongachromene；6-甲酰基-7-甲氧基香豆素；对羟基苯甲酸；对羟基苯甲醛，汉黄芩苷、二苯乙烯苷、绿原酸等共计50多种多酚单体成分；同时，根据多酚色素的抗氧化活性能力，建立了一种甘蔗多酚色素抗氧化活性成分HPLC-DPPH在线筛选法，该方法处理步骤简单，省时省力，实现了在线快速分析甘蔗多酚中的抗氧化活性成分。结合成分分析，研究酚酸及其衍生物和花色苷共呈色反应过程的中间产物变化规律，探讨其非酶褐变的反应历程，阐明了酚酸非酶褐变成色的机制。项目的研究成果有助于理解多酚成分引起制糖过程色素变化的本质问题，为制糖工艺的技术改进提供理论基础及应用价值，同时在果蔬制品加工过程多酚非酶色素的生成及变化方面，也具有重要的学术价值及研究意义。