Résumé
Objective:To elucidate the key medicinal substances that cause the difference of efficacy between lotus leaf and lotus plumule， and to analyze their material basis of "homologous and different effect". Method:UPLC-Q-TOF-MS/MS technique was used to identify the main alkaloids in lotus leaf， lotus latex （juice in lotus petiole） and lotus plumule， chromatographic separation was achieved on a Waters XBridge C18 column （4.6 mm×150 mm， 5 μm）， and gradient elution was performed with 0.1% ammonia aqueous solution （A）-acetonitrile （B） as mobile phase （0-13 min， 35%-60%B； 13-20 min， 60%-80%B； 20-20.1 min， 80%-95%B； 20.1-25 min， 95%B； 25-25.1min， 95%-35%B； 25.1-40 min， 35%B）. Data acquisition was carried out in electrospray ionization （ESI） under the positive ion mode， the scanning range was m/z 100-1 000. Besides， the metabolic network of the main alkaloids was constructed. Result:A total of 5 alkaloids （N-nornuciferine， O-nornuciferine， anonaine， nuciferine and roemerine） were identified from lotus leaf， 6 alkaloids （nuciferine， norisoliensinine， 6-hydroxynorisoliensinine， liensinine， isoliensinine and neferine） in lotus latex， and 8 alkaloids （lotusine， norcoclaurine， N-methylcoclaurine， pronuciferine， armepavine， liensinine， isoliensinine and neferine） in lotus plumule. Also， the biosynthetic pathways of the terminal alkaloids of bisbenzylisoquinoline alkaloids （liensinine， isoliensinine and neferine） and aporphine alkaloids （N-nornuciferine， O-nornuciferine， anonaine， nuciferine and roemerine） was conducted. Conclusion:Five aporphine alkaloids in lotus leaf and three bisbenzylisoquinoline alkaloids in lotus plumule are the material basis for "homologous and different effect" of lotus leaf and lotus plumule. The metabolism of alkaloids in lotus leaf and lotus plumule is derived from the same compound of （S）-N-methylcoclaurine， and two types of alkaloids are synthesized through the action of two different enzymes. The synthetic alkaloids have different structures， resulting in different chemical composition between different tissues， thus producing different efficacy between lotus leaf and lotus plumule.