ABSTRACT
OBJECTIVE：To establish a m ethod for simultaneous determination of neoastilbin ，astilbin，neoisoastilbin，isoastilbin， quercitrin and engeletin in Engelhardia roxburghiana，and conduct multivariate statistical analysis. METHODS ：HPLC-QAMS method was adopted. The determination was performed on Phenomenex SuperLu C 18 column with mobile phase consisted of acetonitrile-0.1％ formic acid （19 ∶ 81，V/V）at the flow rate of 1.0 mL/min. The detection wavelengths were set at 254 nm （neoastilbin，astilbin，neoisoastilbin，isoastilbin，engeletin）and 291 nm（quercitrin）. The column temperature was 30 ℃，and sample size was 10 μL. Using astilbin as internal substance，and the relative correction factors of other 5 factors were calculated. The contents of each component were calculated according to relative correction factor ，and were compared with the results of external standard method. SPSS 22.0 software was used for cluster analysis and principal component analysis. RESULTS ：The linear range of neoastilbin ，astilbin，neoisoastilbin，isoastilbin，quercitrin and engeletin were 0.007-0.311，0.871-18.184，0.002-0.119， 0.052-1.251，0.105-2.202，0.020-2.319 μg（r＞0.999），respectively. RSDs of precision ，reproducibility and stability （24 h）tests were all lower than 3％. The average recoveries were 97.32％，94.89％，97.15％，96.90％，97.52％ and 97.53％（RSDs were 1.09％ -2.60％ ，n＝6），respectively. The relative correction factors of neoastilbin ，neoisoastilbin，isoastilbin，quercitrin and engeletin were 1.252 6，1.198 3，0.958 6，0.807 1 and 1.138 1， respectively. The contents of neoastilbin ， neoisoastilbin， qq.com isoastilbin，quercitrin and engeletin measured by QAMS were 0.394 2-2.067 2，0.139 1-0.804 7，2.864 8-8.554 8，4.581 2- 11.371 1，1.028 9-13.401 5 mg/g；the contents of neoastilbin ， astilbin，neoisoastilbin，isoastilbin，quercitrin and engeletin were 0.367 2-1.925 3，46.361 1-126.342 1，0.138 1-0.798 8，2.966 2-8.857 8， 4.642 5-11.523 3，0.970 6-12.641 9 mg/g，respectively. Relative errors of two methods was lower than or equal to 3.55％. The results of cluster analysis showed that 9 batches of samples could be clustered into two categories ；S8 sample was one category and others were one category. The results of principal component analysis showed that accumulative contribution rate of former 2 principle components was 84.745％，and the results of sample classification were consistent with those of cluster analysis. CONCLUSIONS ： The established HPLC-QAMS method is accurate ，feasible and repeatable ，and can be used for simultaneous determination of 6 flavonoids in E. roxburghiana ，and it can provide reference for quality control.
ABSTRACT
OBJECTIVE:To optimize the extraction and purification technology of total flavonoids from Engelhardia roxburghi-ana,and to establish the method for the content determination of 3 kinds of effective components. METHODS:Using the extrac-tion transfer rate of astilbin as index,single factor test was used to investigate extraction solvent,extraction method,volume frac-tion of percolation solvent ethanol,percolation material-liquid ration,soaking time before percolation and percolation rate of extrac-tion technology,and volume fraction of eluant ethanol in AB-8 resin purification technology. The contents of 3 effective compo-nents as astilbin,texifolin and engelitin in total flavonoids from E. roxburghiana were determined by HPLC. RESULTS:The opti-mal extraction technology was using 70% ethanol as extraction and percolation solvent,percolation extraction,soaking for 8 h be-fore percolation,percolation material-liquid ratio of 1∶16(g/ml),percolation rate of 30 ml/(min·kg). The purification technology was diluting the solution to 0.5 g (crude drug)/ml with water,ethyl acetate extraction,dissolved extract with 50% ethanol after evaporated to dryness,AB-8 resin for sampling,eluted with 50% ethanol,concentrating and drying. In verification test,extraction transfer rate of astilbin was more than 80%(RSD=0.42%,n=3). The contents of astilbin,taxifolin and engeletin in total flavo-noids from E. roxburghiana by purified were 57.94%,3.72% and 2.83%,respectively;the contents of 3 components accounted for 64.00% of total flavonoids. CONCLUSIONS:The extraction and purification technology is stable,rational and reliable;the content determination method of 3 effective components in total flavonoids of E. roxburghiana is accurate,simple and producible.