色氨酸和苏氨酸衍生化红曲红色素的稳定性研究  

Stability of Red Monascus Pigments Derived with Trp and Thr

作　　者：何贝贝 刘彩 陈莎[1] 高梦祥[1] 李利[1] HE Bei-bei;LIU Cai;CHEN Suo;GAO Meng-xiang;LI Li(College of Life Science,Yangtze University,Jingzhou 434025,Hubei,China)

机构地区：[1]长江大学生命科学学院,湖北荆州434025

出　　处：《食品研究与开发》2022年第3期21-27,共7页Food Research and Development

基　　金：国家自然科学基金(31730068)。

摘　　要：该研究以红曲橙色素、色氨酸和苏氨酸为原料,利用亲氨基反应在体外合成色氨酸衍生化的红曲红色素(red Monascus pigments derived with Trp,Trp-RMPs)和苏氨酸衍生化的红曲红色素(red Monascus pigments derived with Thr,Thr-RMPs),并考察rp-RMPs和Thr-RMPs在不同pH值和温度下的稳定性。结果显示:Trp-RMPs和Thr-RMPs呈亮红色,在pH 3~pH 7范围内颜色稳定,最大吸收波长未发生明显位移;Trp-RMPs和Thr-RMPs对热敏感,其热降解符合一级反应动力学模型,在40℃~80℃范围内半衰期随着温度的升高而急剧下降;pH值对Trp-RMPs和Thr-RMPs热稳定性的影响显著,在pH 3~pH 7范围内,pH值越高,半衰期越长,稳定性越好;在pH 3时,Trp-RMPs的热稳定性比Thr-RMPs好,其半衰期显著大于Thr-RMPs,而在pH 5~pH 7时,Trp-RMPs和Thr-RMPs的热稳定性相差不大,半衰期无显著差异。In this study,orange Monascus pigments,along with tryptophan or threonine,were used as precursors for the in vitro synthesis of tryptophan-derivatized red Monascus pigmensts(Trp-RMPs)and threonine-derivatized red Monascus pigments(Thr-RMPs)based on the aminophilic reaction.The stability of Trp-RMPs and Thr-RMPs at different pH and temperature was then investigated.The synthesized Trp-RMPs and Thr-RMPs were bright red in color,and their color was stable in the pH range of 3-7,with no significant shifts in the maximum absorption wavelength.Trp-RMPs and Thr-RMPs were sensitive to heat,and their thermal degradation reactions were in accordance with the first-order kinetics.In the range of 40℃-80℃,the half-life of Trp-RMPs and Thr-RMPs decreased significantly with an increase in temperature.In addition,pH had a remarkable effect on the thermal stability of Trp-RMPs and Thr-RMPs.In the pH range of 3-7,the higher the pH,the longer the half-life and the better the stability.At pH 3,the thermal stability of Trp-RMPs was better than that of Thr-RMPs as the half-life of Trp-RMPs was significantly longer than that of Thr-RMPs;however,in the pH range of 5-7,Trp-RMPs and Thr-RMPs showed similar thermal stability as their half-life did not differ significantly.

关 键 词：氨基酸衍生物 红曲红色素 pH值 温度 稳定性 降解动力学 

分 类 号：TS264.4[轻工技术与工程—发酵工程]