节点文献
烟碱的提取与纯化
Extraction and Purification of Nicotine in Tobacco
【作者】 王美兰;
【作者基本信息】 江南大学 , 粮食、油脂与植物蛋白工程, 2007, 硕士
【摘要】 本论文改进了一种快速稳定的烟碱测定方法-非水滴定法,确定了微波辅助提取烟叶烟碱和制备烟碱粗品的工艺;并以溶剂萃取法对烟碱粗制品纯化,以烟碱和软脂酸的成盐反应精制烟碱。用非水滴定法测定烟叶中烟碱的含量,并与HPLC的测定结果进行比较,稳定可靠、方便快速、准确度、灵敏度均令人满意,特别适合于中、小企业快速、大批量地分析烟草样品中的烟碱,很有实际推广应用价值。经单因素实验和正交实验,确定微波辅助提取的最佳工艺条件:微波辐射时间:6 min功率:600 W,料液比(w·v-1):1∶25。从烟叶水浸提液制备烟碱粗品,工艺条件为:氯仿萃取15 min,体积比(氯仿/水,V/V)1∶1,萃取两次;硫酸反萃时,选择体积比(硫酸水溶液/氯仿,V/V)1∶1,萃取两次,每次10 min。溶剂萃取法纯化烟碱,选择正己烷作为萃取溶剂;优化后的条件为:体积比(正己烷/水,V/V)2:1,萃取时间15 min,萃取4次;烟碱的纯度为95%,得率为38%(烟碱/烟碱粗产品)。利用软脂酸与烟碱的成盐反应,精制烟碱的条件:烟碱5 mL,溶于20 mL正己烷中,软脂酸的最佳用量为1.5 g,反应时间为6 h,选择体积比(正己烷/水,V/V)1∶2,40℃为最佳反应温度。烟碱经烟碱与软脂酸成盐的反应精制后,纯度达到98.8%。各级产品经GC-MS图谱分析,原料烟叶经一系列工艺流程,尤其经软脂酸与烟碱盐制备的步骤,烟碱含量有很大的提高。终产品的烟碱纯度可达98.8%,达到医药级产品的要求。产品中的其他烟草生物碱,尤其是去氢新烟碱、麦斯明在总生物碱中的含量明显降低。
【Abstract】 A fast and stable method of determining nicotine—non-aqueous titration method was improved. Technics of extracting nicotine from tobacco and making unrefined product of nicotine was studied and determined; The unrefined nicotine was purified using solvent extraction and the nicotine was refined by a salification reaction of nicotine and palmitic acid.The content of nicotine in tobacco was determined with non-aqueous titration. Compared with the method using HPLC, non-aqueous titration was more stable, more convenient and faster, and the accuracy and sensitivity of the method were satisfying, especially fitted for fast and mass analysis of nicotine of tobacco sample in medium-sized and small companies. This is a method worth of wide use.Though single factor selecting expriment and orthogonal test,The optimal technics of extraction of nicotine with microwave assisted extraction was determined: microwave radiation time was 6 min, microwave power was 600W and the proportion of material and solvent was 1:25.The technics of making unrefined nicotine from tobacco solution was as follows: first extraction with chloroform for 15 min, the proportion of chloroform and solution was 1:1, the extraction was repeated once. The nicotine was then reextracted with sulfuric acid for two times, 10 min every time, and the proportion of the two phases was also 1:1.The nicotine was purified with solvent extraction. Hexane was chosen as the extraction solvent. The optimal condition was as follows: the proportion of the two phases(hexane/ water) was 2:1, extraction time was 15 min, and the extraction was repeated thee times. The purity of nicotine was 95% and the yield was 38%.The nicotine was refined by salification reaction using palmitic acid and nicotine, the optimal condition was as follows: 5 mL of nicotine was dissolved in 20 mL of hexane, the amount of palmitic acid was 1.5 g, reaction time was 6 h, the proportion of hexane and water was 1:2(V/V) and the optimal reaction temperature was 40℃. The purity of nicotine was 98.8%.Products in different extraction steps were analyzed with GC/MS. The results showed that after a serial of extraction and purification, the concentration of nicotine increased a lot. The purity of nicotine in final product was 98.8%, reaching the requirement of medication product. The proportion of other tobacco alkaloids, like anatabine、myosmine in products lower a lot.