Chemical Components Analysis Of Rheum Lhasaense And Excretion Research Of Piceatannol-3'-O-?-D-glucopyranoside

The dry root of Rheum lhasaense has the pharmacological effects of delaying senescence,improving immunity and protecting nerve cells.The chemical components of rhubarb generally contains stilbene,anthraquinone and polysaccharide compounds,while Lhasa rhubarb is different and does not contain anthraquinone.High performance liquid chromatography tendam with high resolution mass spectrometry(HPLC-HRMS)was used for the separation and identification of chemical components in Rheum lhasaense.The mass data were acquired both in positive and in negative ionization mode.A total of 57 compounds were identified from Rheum lhasaense extract,including 31 Tannins,13 stilbene,2butyrophenones and 11 other compounds.47 of these compounds were first discovered,and enquinones were not found..The method provided a good example for rapid analysis of different types of chemical constituents from Rheum lhasaense.It might be helpful for further phytochemical studies and quality control of Rheum lhasaense.In this paper,another HPLC-HRMS method was established to quantify Piceatannol-3'-O-?-D-glucopyranoside(PG)in rat feces and urine.The external standard method and the least square method were used to perform linear regression on the curves of different matrix.Over the concentration range of 40~2000 ng/mL,PG showed a good linear correlation,R~2 was 0.9926,and the lower limit of quantification was 40 ng/mL,complete methodological verification showed that the method has acceptable accuracy,precision The matrix effect was obvious but reproducable.The verification results showed that the method had the outstanding characteristics of high sensitivity and selectivity.HPLC-HRMS method was used to study the excretion characteristics of PG in rats,and the differences in excretion characteristics from different administration routes and genders were also investigated.Rats were given a single intravenous(i.v.)or intragastric(i.g.)administration at a dose of 40.0 mg/kg or 4.0 mg/kg,respectively.The results showed that,after i.v.or i.g.intravenous administration,no PG was detected in rat fecal samples.And after i.v.administration,the cumulative excretion of PG in female and male rats urine samples were 0.99?0.42%and 3.00?1.25%;after i.g.administration,the cumulative excretion rates were 0.05�0.04%and 0.15�0.04%,respectively.This shows that PG is mainly excreted in urine in rats,and the main excretion form should be metabolites;and significant gender differences are found in the excretion of PG in rat urine(p<0.05).After i.g.or i.v.administration,the excretion rate of PG in rat urine samples reached the maximum at 4-8 h and 2-6 h,respectively,and the excretion rate decreased significantly after 10 h.