The Study Of The Alkaloids Chemical Composition In The Huperzia Serrata

Huperzia serrata, is the whole herba of perennial herbaceous plant of huperzia serrata. In folk, it was widely used in the treatment of pneumonia, injuries, hemorrhoids hematochezia, swelling and other diseases.Researches showed that, there are a lot of alkaloids in the huperzia serrata. Parts of them have anti-acetylcholinesterase effects and can improve the effectiveness of learning and memory. It also have broad application prospects in clinical medicine, food and health products. So the separation and analysis of alkaloids in the huperzia serrata have becoming a research hotspot. This paper used the total alkaloids extracts of huperzia serrata as research object. First, we set up a rapid research method to identify the structure of alkaloids in the huperzia serrata by using UPLC-Q-TOF-MS technology, it provides scientific basis for the separation and application of alkaloids. Second, this paper separated the alkaloid extracts by using modern chromatography methods and identified the structures according to the NMR information. It provides theoretical basis for the development and utilization of alkaloids. The main contents and conclusions are as follow:(1) This paper used UPLC-Q-TOF-MS in the positive ion mode and selected 25ev and 45ev collision energy to test the alkaloid sample. By analyzing the mass spectrum information, 24 alkaloid compounds were identified. Half of them are fawcettimine-type alkaloid, a quarter of them are lycopodine-type alkaloid and others are miscellaneous-type alkaloid. In the condition of 25ev collision energy, the alkaloids mainly take off the-OH, O atom and other functional groups which on the side chain to form the fragment ion peak of (M+-17) or (M+-16). And in the condition of 45ev collision energy, fawcettimine-type alkaloids are easily to remove the-C=O bond to form the characteristic fragment ion peak of (M+-28), and after that the ring will break to form the characteristic fragment ion peak of m/z152. After losing the-OH or O atom on the side chain, the Lycopodine-type alkaloids will continue to crack to form the base peak of m/z105 or m/z137. And the miscellaneous-type alkaloids will take off one or more hexatomic rings after losing the side chain to form the base peak of m/z263 orm/z150.(2) This paper isolated and purified 3 alkaloid monomeric compounds by using the methods of silica gel column chromatography, Sephadex LH-20 column chromatography, TLC and so on. Test these monomeric compounds by using the technology of 13C-NMR and 1H-NMR and identify its structure according to NMR information and references. The results showed that, compound 1 and compound 2 respectively are huperzina A and 6α-hydroxylycopodine. Because of the poor solubility of compound 3, we can not identify its structure for further. In the experimental process, we also got 2 non-alkaloid monomeric compounds. They belong to triterpenoids. Compound 4 is 21β-hydroxy-serrat-14-en-3β-ol and compound 5 is 21α-hydroxy-serrat-14-en-3β-yl-acetate.