Isolation And Elucidation Of The Alkaloid From Carica Papaya L

There are abundant biological active compounds and important biologicalactivities in Carica Papaya L., Until now, few studies have been done on itscomponents. The main alkaloids of papaya leaves and fruits were separated andidentified in this thesis. The main contents were as follows:(1) Alkaloids were researched by the method of precipitation, thin layerchromatography (TLC) and LC-MS. Carpaine, pseudocarpaine, dehydrocarpaineâ… and dehydrocarpaineâ…¡ were detectedsuccessfully in the papaya leaves. Carpaine andother two unknown alkaloids were also found in the papaya fruit.(2) The alkaloid of papaya leaves was separated and purified by methods ofsilica gel column chromatography and chemical precipitation respectively. Threeprecipitates (â… , â…¡, â…¢) were obtained.Precipitates (â… ,â…¡) were identified as carpaineand precipitate(â…¢) was speculated to be dehydrocarpaineâ…  which were analyzed byultraviolet spectrum (UV), fourier transform infrared spectroscopy (FTIR), massspectrum (MS) and nuclear magnetic resonance (NMR).(3) A quantitative method of carpaine was established by HPLC for the first time.The chromatographic column was Waters XBridgeTMC18, and the mobile phase wasacetonitrile and ammonium acetate (pH8.50.05mol/L). The elution condition was alinear gradient at the flow of0.8mL/min with A (acetonitrile) and B (ammoniumacetate):0min,25%A and75%B;5min,25%A and75%B;15min,40%A and60%B;30min,40%A and60%B;35min,100%A and0%B;40min,100%A and0%B;45min,25%A and75%B;55min,25%A and75%B. The detection wascarried out by a PAD detector at304nm, and the column temperature was roomtemperature.(4) The quantitative method was verified by the statistical methods. The averagerecovery of carpaine was98.86%. RSDs of repeatability, within-day, between-dayand peak area was0.062%,0.061%,0.065%and1.0%respectively. Therefore, thismethod had a good repeatability, high accuracy and stability. The purity of carpainewhich prepared by separation was95.35%and the content of carpaine in the papaya powder of leaves and fruits were respectively0.930mg/g and0.036mg/g. Thecarpaine was not found in the papaya seeds.(5) A preparation route of the coarse alkaloid of papaya leaves was designed.The yield of coarse alkaloid was0.4188%, in which the content of carpaine was17.57%, and the extraction rate of carpaine was79.12%.