柠檬草微量元素的测定及黄酮提取的总汇.doc

玉林师范学院本科生毕业论文（设计） 柠檬草微量元素的测定及黄酮提取的研究 Study on Determinating of Trace Elements and Extracting of Flavonoids from Lemongress Wormwood Leaves 院 系 化学与材料学院 专 业 应用化学 班 级 应化09班 姓 名 黎兰茜 学 号 200906404101 指导教师单位 化学与材料学院 指导教师姓名 黄志伟 指导教师职称 副教授 柠檬草微量元素的测定及黄酮提取的研究 应用化学2009级 黎兰茜 指导老师 黄志伟 摘要 本研究主要采用微波消解处理样品柠檬草，用浓HNO3 —HClO4和HNO3—H2O2对样品柠檬草进行消解，然后用火焰原子吸收光谱法测定柠檬草中的铜、锌、钙、锰、铁等微量元素的含量。结果表明，柠檬草中含有丰富的铜、锌、钙、锰、铁这五种人体必需的微量元素。该方法可操作性强、测定快速、简单、结果准确，对研究柠檬草中的微量元素含量提供了有效,准确的数据。同时采用正交试验法研究柠檬草中总黄酮的提取工艺,考察了乙醇含量、提取时间、提取次数、以及料液比等4个因素对柠檬草总黄酮含量的影响。确立了柠檬草总黄酮最佳提取条件为:70%的乙醇,提取时间为0.5h,提取次数为3次,料液比为1:15。 关键词：柠檬草，微波消解，微量元素，火焰原子吸收光谱，总黄酮，正交试验 Study on Determinating of Trace Elements and Extracting of Flavonoids from Lemongress Wormwood Leaves Applied Chemistry 2009 LiLan-Xi Supervisor HuangZhi-wei Abstract This study handles sample Lemongress mainly by the means of microwave digestion and wet digestion. We, at first,digest the sample with thick HNO3-HClO4 and HNO3-H2O2 and then determine the content of the calcium,iron,copper,potassium,lead,sodium sincluded in the sample by the means of flame atomic absorption spectrometry. The experiment shows Lemongress is rich in calcium, iron,magnesium,zinc,manganese. And these five trace elements are essential for human body. It can be operated easily and determined fast and quickly and accurate. For the Lemongress study of trace elements provide an effective and accurate data. And extraction technology of flavonoids in Lemongress,was studied by means of orthogonal e xperiment. The effects of the ethanol concentration,the extracting time,the number of extraction times,and the ratio of mass of raw material to the volume of solvent on flavonoid content were inves tigated. Optimum extraction condition was determined as follows: 70% ethanol as extracting solvent,time is 0.5 h,3 times of extraction,the ratio