摘 要:本文采用均匀设计法研究了超声辅助乙醇混合溶剂提取火棘果色素的最佳提取工艺;采用游离基清除法对提取物进行了抗氧化活性评价;在不同酸度、温度、日照时间等条件下对提取物进行了稳定性研究;采用薄层色谱法、液质联用法和核磁共振法对色素进行分离纯化及结构的解析。结果显示,均匀设计法优选出了在390nm处最佳条件为74。185% pH2。5乙醇酸性溶液、超声时间为31min;在663nm处最佳条件为超声功率为25%、超声时间为67min;390nm处在最佳条件下的提取率为29。3%,663nm处最佳条件下提取率为20。2%;抗氧化活性实验得到羟基自由基、超氧自由基和DPPH·的IC50值分别为22。63mg/ml、37。37mg/ml、26。35mg/ml;由稳定性试验得出在390nm处,随着pH、温度、日照时间和碳水化合物浓度的增大,色素提取液的稳定性下降;随着金属离子加入时间增长,稳定性增强;在663nm处pH 1。7,60℃,光照0。5h时色素最稳定,碳水化合物随着浓度增大,稳定性先下降后上升,随着金属离子加入时间的增长,除了钙离子使稳定性下降外其余都增强。结构解析得到最多量色素基本确定为锦葵花素-3-0-三葡糖苷。以上结果表明,均匀设计法可得到优化的火棘果色素提取率,所得提取物具有较好的抗氧化活性和稳定性,淮安产火棘果可用于食品色素的提取原料。94159
毕业论文关键词:火棘果,超声提取法,均匀设计法,稳定性,抗氧化活性,核磁共振氢谱,液质联用
Abstract: In this paper, the optimum extraction technology of pigment from pyracantha fortuneana was studied by using ultrasonic assisted ethanol mixed solven。 Free radical scavenging method was used to study antioxidant activity of extracted pigment and stability was studied by adding acidity, carbohydrates and metal ion in extract and changing temperature, sunshine time。 The separation and purification of the pigment and the analysis of the structure were carried out by thin layer chromatography, nuclear magnetic resonance and liquid chromatography combined with。mass spectrum The results showed that the optimum conditions were 74。2 % pH2。5 ethanolic acid solution, the ultrasonic time 31min at 390nm; the optimum conditions were 66% power and the ultrasonic time 67min at 663nm; The optimum extraction conditions were 29。3% at 390 nm and 20。2% at 663 nm。 The IC50 values of extract scavenging on hydroxyl radical, superoxide radical and DPPH were 22。63mg/ml, 37。37mg/ml and 26。35mg/ml respectively。 The stability of the pigment at 390nm decreased with the increase of pH, temperature, sunshine and carbohydrates, while the metal ions was opposite and the most stable conditions at 663nm were pH 1。7, 60 ℃ and light 0。5h; it first was rise then fall with the increase of carbohydrates and the stability was enhanced with increasing the concentration of metal ions except the calcium ion。 The structure of the largest amount of the extracted pigment might be Malvidin-3-O-glucoside chloride 。The results showed that the optimal extraction method could improve the extraction rate of the pigment of Pyracantha fortunei, and the pigment has good antioxidant activity and stability。 Pyracantha fortunei fruit of Huai'an could be used as crude to extract pigment。
Keywords:pyracantha fortuneana, Uniform Design, stability, 1HNMR, HPLC-MS
目 录
1 引言 4
2 实验部分 5
2。1 材料、仪器与试剂 5
2。2 色素的提取 6
2。2。1原料的预处理 6
2。2。2确定最佳pH和最佳料液比