红檵木花色素的微波提取与特性研究

Microwave-assisted Extraction Techniques and Some Properties of Anthocyanidin in Loropetalum chinense var.rubrum Flowers

对红檵木花色素的理化性质及微波提取方法进行了研究 .结果表明 :红檵木红色素可能属醇溶性黄酮类 ,其耐酸、耐氧化性很好 ,耐光氧化和耐热处理性极佳 ,而耐碱性和耐 Fe2 +、Fe3+、Cu2 +、Pb2 +盐离子性较差 .微波提取工艺研究表明 :微波提取时间在设定的提取工艺三因素中居主要影响 ,其次是乙醇用量和浓度 ;只需一次微波处理便可将花瓣中红色素提完 .进一步研究该色素的光照和热处理降解特性 ,结果表明 :在设定的各处理温度下 ,该红色素降解均很缓慢 ,但其降解速度随设定处理温度升高呈加快趋势 .在 90℃～ 10 0℃的热处理下 ,其降解速度与热处理时间有 A 最大光吸收 ～ t及 ln A～ t线性相关关系 ;当低于 90℃时 ,仅 80℃的设定热处理下有 ln A～ t直线相关 ,而 A～ t间都不呈线性关系 .连续光照处理中 ,随处理时间延长其降解幅度极小 ,降解速度与光照时间不存在 A～ t及 ln A～

The microwave-assisted extraction and the properties of L.chinense (R.Br) Oliv.var.rubrum Yieh.anthocyanidin were studied.Results showed that anthocyanidin maybe was a flavone soluble in EtOH,and very stable to acid,oxidant,light and heating-treatments,but sensitive to alkaline and Fe^(2+),Fe^(3+),Cu^(2+),Pb^(2+) conditions.With only one pre-microwave treatment,all red pigments in petals were extracted with 30% EtOH,and the three dominant factors affecting the extraction were the duration of microwave treatment,the operational volume and concentration of EtOH.The degradation rate of the red pigments by light and heating-treatments showed that the degradation rate of anthocyanidin at different temperatures was very slow,but it tended to increase with increased temperatures.Between the degradation rate and heating-treatment time,there was a A^t and lnA^t linear correlation within 90℃~100℃,but only the lnA^t showed a linear correlation at 80℃ when heating-treatment temperature was lower than 90℃.There was no A^t and lnA^t linear correlation between degradation rate and light treatment time,and degradation rate of anthocyanidin was hardly affected by no-stop light.