节点文献
新疆紫茉莉黄酮类化合物及色素的初步研究
Preliminary Study on Flavonoid Contents and Pigments of Mirabilis Jalapa L.in Xinjiang
【作者】 李凌智;
【导师】 阿不都拉·阿巴斯;
【作者基本信息】 新疆大学 , 食品科学, 2010, 硕士
【摘要】 本论文主要研究了新疆紫茉莉中黄酮类化合物的提取方法、提取条件、纯化和初步的鉴定及紫茉莉花中色素的提取方法、提取条件和稳定性。主要内容如下:通过对紫茉莉花和叶子的预试验,确定其中含有黄酮类化合物。以芦丁标准品为对照品,采用分光光度法对紫茉莉茎、叶、花和种子的总黄酮含量进行了测定,紫茉莉不同部位中以花中总黄酮含量最高。紫茉莉花中黄酮类化合物的提取采用加热回流法,分别考察了料液比、提取时间、提取温度和乙醇浓度对提取率的影响,采用响应面法建立总黄酮二次多项回归模型方程,并进行回归分析。得最佳工艺条件:料液比为1:18,提取时间2.74h,温度60.73℃,乙醇浓度74.93%,最佳提取级数为1级。产品得率可达7.784%。用AB-8大孔吸附树脂对紫茉莉花中黄酮类化合物进行纯化。吸附最佳工艺条件为:吸附时间为3.5 h,上样浓度为0.4mg/ml;解吸最佳工艺条件为:乙醇浓度为50%,解吸剂用量为96ml左右。得到的精制黄酮类化合物可能主要含有黄烷酮、查耳酮或二氢黄酮(醇)类。紫茉莉花中色素的提取采用传统加热回流法,分别考察了料液比、提取时间、提取温度和乙醇浓度对提取率的影响,通过正交试验及方差分析,确定了紫茉莉花色素的最佳提取工艺条件:料液比为1:18,提取时间为2.5h,提取温度为65℃,乙醇浓度为70%,提取级数:1级。色素稳定性试验表明:紫茉莉花色素在酸性和中性环境下较稳定;温度小于60℃时较稳定;不同金属离子对紫茉莉色素的影响也不同,Mg2+具增强效果,Fe3+明显导致色素稳定性减弱,K+、Cu2+、Zn2+、Ca2+均引起色素变黄;甜味剂表现出明显增色效果;低浓度的柠檬酸对色素稳定性有明显增强作用;抗坏血酸的加入导致色素稳定性下降。
【Abstract】 The research is focused on extraction method and extraction condition of the flavonoids and pigment from the Mirabilis jalapa L.of Xinjiang, the flavonoids was purified and carried on preliminary appraised to its structure and the pigment solution stability,The major contents of the research were followed as:It proved that flavonoids was existed in the flower and leaves of Mirabilis jalapa L. by pre-test. Taking rutin as a contrast, we studied the total content of flanovoids in different part of Mirabilis jalapa L. (stem, leaves, flower and seed), by spectrophotometry. The results showed that the total content of flavonoids was the highest in flower. The extraction technology of flavonoids from the flower of Mirabilis jalapa L. used traditional hot organic solvent method. The extraction rate of flavonoids optimized conditions(ratio of solid to liquid, extraction time , extraction temperature and ethanol concentration) were determined by Response surface methodology (RSM) and a mathematical regression model with the macroporous resin built. The result showed that the optimized conditions included: the ratio of solid to liquid is 1:18, extraction time is 2.74h, extraction temperature is 60.73℃, ethanol concentration is 74.93% and extraction frequency is once time; and extract yield is 7.784%.Flavonoids was purified with the AB-8 pocket adsorption resin. Results showed that the optimal adsorption parameters were adsorptive time 3.5h, solution concentration 0.4mg·mL-1 and the optimal desorbtion parameters are 50% ethanol as eluting solvent, the ethanol volume 96ml. Purification flavonoids mainly contains chalcone, dihydroflavone or dihydroflavonol.The extraction technology of pigment from the flower of Mirabilis jalapa L. used traditional hot organic solvent method. The extraction rate of pigment optimized condition(ratio of solid to liquid, extraction time , extraction temperature and ethanol concentration) were determined by orthogonal design. The result showed that the optimized conditions included: the ratio of solid to liquid is 1:18, extraction time is 2.5h, extraction temperature is 65℃, ethanol concentration is 70% and extraction frequency is once time.The result of pigment stability showed: Pigment stability was maintained under acidic and neupral condition and below 60℃. Magnesium(Ⅱ) exhibited positive effects on the stability while iron(III) accelerated the degradation of the pigments. The colour turned yellow by addition of totassium(Ⅰ)、copper (Ⅱ)、zinc(Ⅱ)、calcium(Ⅱ). pigment stability was enhanced by addition of sweetener and low concentration of citric acid and decreased by addition of VC.
【Key words】 Mirabilis jalapa L.; flavonoids; pigment; response surface; purify;