Studies On The Method Of Content Determination Of Two Alkaloids In Zanthoxylum Nitidum (ROXB.)DC. And Separation Them By Cation Exchange Resin

Objective: To study the simultaneous HPLC determination of ethoxy- chelerythrine and nitidine chloride from Zanthoxylum Nitidine(Roxb.) DC and determine a good separation process of them by cation exchange resin.Method:The indexes of treating methods, mobile phase, standard linear ranges and recovery rates of ethoxychelerythrine and nitidine chloride from Zantho- xylum Nitidine were determined by Hypersil BDS C18 (250 mm×4.6 mm, 5μm) .Using HPLC and absorption-desorption of detection method,we compared with adorption rate and desorption rate of ethoxychelerythrine and nitidine chloride by 7 kinds of resins,then chose resin D001AM and resin 122 to detailed research.Studies on resin's adsorption kinetics, the maximal bearing capacity,the sample's ethanol concentration, the sample's pH, the sample's concentration and the desorption's species, we could choose resin D001AM to optimize.Studies on the effect of resin's D001AM adsorption number,the influence of temperature on the adsorption,the elution of impurity, the desorption's optimization, we could obtain the optimum process. Results:The determination of ethoxychelerythrine and nitidine chloride in Zanthoxylum Nitidum (Roxb.) DC:Using acetonitrile -water-triethylamin- phosphoric acid (25:75:1:1)as mobile phase, the flow rate was 1 mL/min with ulteaviolet detection wavelength at 270nm.The calibration curve of ethoxy- chelerythrine was linear between 2 ~32 mg/L (r=0.9999). The average recovery rate was 96.80% and RSD was 1.43%. The calibration curve of nitidine chloride was linear between 2 ~32 mg/L (r=0.9999). The average recovery rate was 97.91% and RSD was 1.20%.The optimal separation process of ethoxy- chelerythrine and nitidine chloride from zanthoxylum nitidum: zanthoxylum nitidum was extracted for 3 times with 60% ethanol,combined the extraction. The extraction rate of the total alkaloids was 91.34%, ethoxychelerythrine was 85.38% and nitidine chloride was 88.64%.The process was verified with this ex- traction.Static absorption-desorption method was adopted to selecte the optimal resin- D001AM from 7 kinds of resins.The obtained desorption from fractional desorption with 4%NaHC03-25%EtOH and 3.0 mol/L HCl-70%EtOH was centrifuged. The average adsorption rate and desorption rate of ethoxy- chelerythrine was 90.86% and 100.99% and the extraction rate was 78.89%; the average adsorption rate and desorption rate of nitidine chloride was 97.26% and 71.66% and the extraction rate was 61.18%.Conclusion:The cation exchange resin of D001AM is a simple ,economic resin when it extract and seprate ethoxychelerythrine and nitidine chloride simultaneously from Zanthoxylum Nitidum with high adsorption rate, desorption rate and avoid using a mass of chloroform . There migth be potential industrial value.