Studies On Chemical Constituents From Roots Of Euphorbia Pekinensis Rupr

The roots of Euphorbia pekinensis Rupr, as one original medicine herb that was called "Jingdaji". It is a traditional Chinese medicine and has been widely applied in treating edema, hydrothorax, phlegm-fluid retention, breath with cough and other diseases for a long time. Modern pharmacology research shows that the roots of Euphorbia pekinensis Rupr is useful for diuresis, analgesic, anticancer, and antiinflammation.As the extracting solvent, the methanol was employed to extract the powders of roots of Euphorbia pekinensis Rupr at heat reflux condition in the electric-heated thermostatic water bath for three times. After the methanol was evaporated in vacuum,250g the crude extracts was obtained from 2Kg herb material. The extracts were subjected to column chromatography of Silica gel, ODS, sephadex gel and even recrystallization respectively before seven natural compounds were separated and purified. All the chemical strutures of the seven compounds were elucidated after analyzing spectra data of 1D-NMR(13C NMR,1H NMR, DEPT), MS,IR and UV.Moreover, for the purpose of knowing the contents of representative compounds in the herb, two triterpenoids tirucallol and euphol were analyzed simultaneity by HPLC-UV method for first time. A series of tests, including Matrix solid-phase dispersion (MSPD) in the extracting progress, were operated and proved that it was a veracious method with high sensitivity, precision and time saving.1. The results of extraction and Isolation1.1 Extraction2kg the roots of Euphorbia pekinensis Rupr was crushed and refluxed three times respectively by 25L,20L, and 15L 95% methanol for 2h,1.5h, and 1h. The extracting solution was collected and filtered. The 250g crude extract was obtained by vacuum recovery of methanol.1.2 SeparationThe crude extract was further extracted by silica gel column chromatography, and three compositions were achieved, including A (90mgⅡ,200mgⅢ, and 178mgⅣ), B (70mgⅠand 100mgⅤ) and C (1.1 gⅥand 1.4gⅦ). Seven compounds were gained after the extracts were isolated by the column chromatography and recrystallization as compounds错误!未找到引用源。(70mg),错误!未找到引用源。(90mg),错误!未找到引用源。(200mg),错误!未找到引用源。(178mg),错误!未找到引用源。(100mg),错误!未找到引用源。(1．1g) andⅦ(1.4g)。1.3 The results of identificationThe spectra of NMR,MS, IR,UV analysis elicited the Compounds错误!未找到引用源。-VII were ioctacosyl ferulate, dibutyl phthalate, euphol, tirucallol, obtusifoliol,β-sitosterol, daucosterol.. Dibutyl phthalate and obtusifoliol were gained the first tme from the roots of Euphorbia pekinensis Rupr.2.The results of centents determination of euphol and tirucallol2.1 Instruments and reagentsInstruments:Agilent 1200 Series HPLC, Eclipse SDB-C18 columm (250 mm×4.6 mm,5μm), VWD UV detector.Reagents:Acetonitrile was HPLC grade. Methanol, ethyl acetate, dichloromethane, and cyclohexane were analytical-reagent grade and employed without any purification.2.2 Methods and results2.2.1 The resuts of MSPD in the extractBy using MSPD technique, the experiment was finally optimized:ODS was used as dispersant,10 mL ethyl acetate was used as eluent, and the ratio was 4:1. The results indicated that compounds III and IV can be extracted effectively. The method was much easier and safer than traditional extraction methods.2.2.2 ChromatographyThe moving phase was acetonitrile-methanol-water (49:49:2). The flow rate was 1.5 mL·min-1. The detection wavelength was 210nm. The temperature was 30℃.2.2.3 The standard curveThe contents of mixture standard solution were preparated in the range from 0.01 to 0.50 mg.mL-1 (both compoundⅢandⅣ) and the linearity of compoundsⅢand错误!未找到引用源。were best and it is showed as follow: 2.2.4 PrecisionThe RSD (n=6) of peak area for compoundsⅢandⅣwere 0.64% and 0.79%, respectively.2.2.5 Reproducibility.The RSD (n=6) of content for compoundsⅢandⅣwere 1.06% and 1.67%, respectively.2.2.6 StabilityCompoundⅢand错误!未找到引用源。showed its high stability during 10 hours because their time and area of the peaks were keep in small change (RSD<2%).2.2.7 Limit of detectionDetectabilities were tested to be 20ng after the concentration of compoundⅢand错误!未找到引用源。mixture standard solution was diluted to 0.0005 mg·ml-1 and gave its S/N≥3.2.2.8 Coefficient of recoveryThe average coefficient of recovery for compoundsⅢandⅣwere 96.88% (RSD=0.39%),96.82%(RSD=1.44%).2.2.9 The content determination of compoundsⅢandⅣThe contents of compoundsⅢandⅣwere 0.418% and 0.186% in average, respectively.In conclusion, all the results of the paper could offer a basic for establishment of quality standards of "Jingdaji", also they could provide science foundation of this medicine herb for the utilization in reason.