Studies On Chemical Constituents Of Euphorbia Pekinensis Rupr

"Jing Daji", the root of Euphorbia pekinensis Rupr,is widely used for treatment of edema,removing the full bilge, pleurisy and schizophrenia etc. So far, there are many researches in chemical constituents and pharmacological function of the root of Euphorbia pekinensis Rupr., but there isn't report about the index of content determination in it's literatures. For the sake of the better use of this herb medicine, this paper describes the extraction, isolation and identification. Moreover, the determination method has been established for content of euphol in the root of Euphorbia pekinensis Rupr in this paper. A series of tests proved that the determination method is accurate, reliable and reproducible to determine euphol in the root of Euphorbia pekinensis Rupr.Extraction and SeparationDried roots (5kg) were extracted by heat reflux in 90% Ethanol (solvent volume were 30, 25 and 20 L , respectively ) for three times (2,1.5 and 1h, respectively), the ethanol was evaporated in vacuum and concentrated to cream. The cream was subjected to silica gel column chromatography eluted with ethyl acetate– methanol– water (5:1:0.5) to afford compounds A (300mg),B (50mg),C (50mg),D (90mg) E(350mg),F(80mg) and G(60mg).Compounds A, B, C, D, E, F and G were identified respectively by UV, IR,MS, and 1DNMR as 3,3′-di-O-methyl-ellagic acid-4′-O-β-D-xylopyranoside , 3,3′-di-O–methyl-ellagic acid-4-O-β-D-glucopyranoside, 3, 3′-di-O-methyl-ellagic acid, Octacosyl ferulate, euphol,β-sitosterol and daucosterol.The content determination of euphol in root of the Euphorbia pekinensis Rupr was studied in the paper. We present a more sensitive and accurate quanti-fication method by HPLC for determining the major chemical constituent-euph- ol in root of the Euphorbia pekinensis Rupr.HPLC was performed on Agilent 1200 HPLC instrument and a Eclipse SDB-C18 column(250 mm×4.6 mm,5μm)at 25℃with the rate of 1.0 ml/min,using the mixture of acetonitrile, methanol and water as mobile phase (49:49:2).Conclusions:ⅰThe linear range of euphol is 0.1μg～5.0μg. y=846.00x+17.00 r=0.9999ⅱEuphol solution was injected into HPLC for six times, the RSD of precision tests is 0.44 % (n=6).ⅲThe repeatability tests for six samples showed RSD of euphol was 1.75%, (n=6) respectively.ⅳThe S/N was 3.1 after the concentration of euphol solution had been diluted to 0.0005 mg/ml and had been determined by HPLC, So the detectability is 0.01μg (10ng)。ⅴThe test of stability showed its RSD was 0.64%, so the euphol solution is stable in ten hours.ⅵThe average recovery of euphol was 100.4%( RSD=0.99% ), ( n=6)。The results of this paper can provide a new index of content determination for establishment of quality standards of the root of Euphorbia pekinensis Rupr. and also can offer science foundation for the development and utilization of this medicinal plant.