摘要
采用紫外-可见光谱(UV-Vis)和傅里叶变换红外光谱(FTIR)法分析辣椒红素在外源活性氧·O-2,H2O2和·OH以及在POD,CAT和LOX防御体系中的结构变化特征。结果表明,外源活性氧处理后辣椒红素最大紫外-可见光吸收峰均出现蓝移现象,其中·O-2和·OH处理后产物FTIR谱峰数减少,峰强变弱,峰形变宽;与色素分子中的羰基和环外烯基发生氧化反应生成烷基和羟基,·OH对色素分子CC具有加成作用;H2O2处理后色素特征峰和强势峰均向低波数位移,产物中含环氧醚基团;在H2O2+CAT/POD防御体系中辣椒红素UV-Vis和FTIR光谱特征无明显变化;在亚油酸+LOX体系中色素分子结构发生断裂,产物不含羰基。可见活性氧处理及在LOX底物体系中,辣椒红素分子反应前后UV-Vis和FTIR等光谱特征发生明显变化,色素分子中长烯链断裂,大共轭体系缩短或被破坏,分子中的共轭双键和羰基等发色基团改变,最终生成醇类或醚类等小分子无色物质;而防御酶CAT和POD能减少活性氧对辣椒红素分子的破坏作用。研究结果丰富完善了辣椒色素理论,同时为其开发利用提供了有价值的技术参考依据。
The changes of UV-Vis and FTIR spectroscopic properties for capsanthin before and after reaction with exogenous su-peroxide anion（＆#183; O2-） ,hydrogen peroxide（H2O2 ） and hydroxyl radical（＆#183; OH） ,catalase（CAT） ,peroxidase（POD） and lipoxy-genase（LOX） were explored .The results showed that ,the UV-Vis spectral absorption of capsanthin treated with reactive oxy-gen species had a blue-shift .At the same time ,the FTIR spectra changed significantly .The number of FTIR spectral peaks re-duced and theFTIR strength weakened for capsanthin molecule treated with ＆#183; O2- and ＆#183; OH .The characteristic and strong peaks moved to shorter wavelengths when treated with H2O2 .And LOX caused breakage of capsanthin molecule and reduction of＆amp;nbsp;peak number or groups without carbonyl .Exogenous H2 O2 ＋CAT or H2 O2 ＋ POD treatment could not affect the UV-Vis and FTIR spectra significantly .So ROS could cause oxidative degradation of capsanthin and destroy chromophoric groups such as carbon-carbon double bond and carbonyl ,then grow colorless alcohols .Hence ROS and LOX should transforms the conjugate system of capsanthin molecules ,while CAT and POD could protect the capsanthin .
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2014年第2期358-363,共6页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(31060228/C200301)资助
