摘要:本论文的主要研究了不同环境对麦冬果实蓝色素稳定性的影响:采用游离 基清除法对提取物进行抗氧化活性评价;采用薄层色谱法分离提纯色素,结合核 磁共振、质谱、红外对麦冬果实蓝色素进行结构的分析。结果显示,提取色素在 紫外可见光区有 2 个吸收峰,波长分别为 473nm 和 529nm,葡萄糖、蔗糖等碳水化 合物对色素的稳定性起到了增强的作用,30℃以上时,色素水溶液中会产生沉淀, 60℃以下时可以保持其蓝色不变,光照对蓝色素吸光度的影响不大;大多数常见 金属离子可使麦冬果实蓝色素吸光值增加,其中 Na+、K+影响比较显著;提取色素 对超氧负离子自由基、DPPH 自由基和 OH 自由基清除率的 IC50 值分别为 28。9mg/ml、 88。1mg/ml、32。2mg/ml。麦冬果实蓝色素的结构大致为芍药花色素苷。以上结果 表明,麦冬果实蓝色素具有一定的稳定性和抗氧化活性,蓝色素属于带有多个糖 分子的花青素类化合物,淮安产麦冬果可用于食品色素的提取原料。92914
毕业论文关键词:麦冬果实、蓝色素、稳定性、抗氧化性、结构鉴定
Abstract: This paper mainly studied the effects of different environmental conditions on the stability of the blue pigment from Ophiopogon japonicus Fruit;free radical scavenging method was used to study antioxidant activity of extracted pigment;The separation and purification of the pigment were carried out by thin layer chromatography and the structure of the purified pigment was characterized by IR, MS, 1HNMR and 13CNMR。 The results showed that the pigment is found to has two absorption wavelengths, 473 and 529 nm。 The carbohydrates such as glucose and sucrose etc can improve the stability of the blue pigment。 When temperature is lower than 60℃, the blue pigment has no change in color, but when temperature is higher than 30℃, some precipitates appear in the pigment solution。 The pigment is greatly affected by pH。 Most metal ions can enhance its absorbance, and few metal ions have obvious effects on it, such as Na+ and K+。 The IC50 values of extract scavenging on superoxide radical 、 DPPH and hydroxyl radical were 28。9mg/ml, 88。1mg/ml and 32。2mg/ml respectively。 The structure of the largest amount of the extracted pigment might be peonidin -3-O-glucoside chloride。 From what has been discussed above, the pigment has good antioxidant activity and stability, the blue pigment is an anthocyanin compound with a number of sugar molecules, Ophiopogon japonicus fruit of Huai'an could be used as crude to extract pigment。
Key words:Ophiopogogon japonicasfruit, blue pigment, stability, antioxidant activity, strucral identification
目 录
1。引言 5
2。实验部分 5
2。1 材料与制备、仪器与器材 5
2。1。1 材料与制备 5
2。1。2 仪器 5
2。1。3 试剂 6
2。2 麦冬果实色素的光谱特征 6
2。3 麦冬果实色素稳定性的研究 6
2。3。1 碳水化合物对麦冬果色素稳定性的影响 6
2。3。2 pH 值对麦冬果色素稳定性的影响 6
2。3。3 温度对麦冬果色素稳定性的影响 6
2。3。4 光照对麦冬果色素稳定性的影响 7
2。3。5 金属离子对麦冬果色素稳定性的影响