Study On Chemical Differentiation Of Different Types Of Panax Genus Products By Using Plant Metabolomics

In this study,the LC-MS-based plant metabolomics approach was applied to discriminate different ginseng products and discover analytical markers.The detail works are as follows:1.Chemical differentiation and quantitative analysis of different types of Panax genus stem-Leaf based on a plant metabolomics approach.Two quantitative methods using-ESI full scan and-ESI PRM MS were developed to analyze ginsenosides in ginseng stem-leaf by using UHPLC-Q-Exactive Orbitrap/MS.By means of-ESI PRM MS method,the contents of eighteen ginsenosides in Asian ginseng stem-leaf(ASGSL)and American ginseng stem-leaf(AMGSL)were analyzed.The principal component analysis(PCA)model was built to discriminate Asian ginseng stem-leaf(ASGSL)from American ginseng stem-leaf(AMGSL)based on-ESI PRM MS data,and six ginsenosides(F11,Rf,R2,F1,Rb1,and Rb3)were obtained as the markers.To further explore the differences between cultivated ginseng stem-leaf and forest ginseng stem-leaf,the partial least squares-discriminant analysis(PLS-DA)model was built based on-ESI full scan data.And twenty-six markers were selected to discriminate cultivated ginseng stem-leaf(CGSL)from forest ginseng stem-leaf(FGSL).This study provides reliable and effective methods to quantify and discriminate among different types of ginseng stem-leaf in the commercial market.2.A discrimination study of Asia ginseng and America ginseng by a comparison of ginsenosides,oligosaccharides and amino acids using a targeted plant metabolomics approach.A quantitative analysis of ginseng chemical ingredients was established using UHPLCMS,in which the concentrations of ginsenosides,oligosaccharides,and amino acids in ginseng were determined.Unlike the C18 column,which showed good performance in the determination of ginsenosides,the NH2 column was used in this method,and it exhibited good separation abilities for three types of compounds,including 6 saponins,4 oligosaccharides,and 15 amino acids.For each type of compound,a recovery of 88%–111%,with relative standard deviations(RSD)better than 6%(n=6)were obtained;the limits of quantification(LOQ)for three types of substances were less than 1?g/mL.Furthermore,the method showed strong ability on the discrimination Asia Ginseng and America Ginseng,and was confirmed to be robust,selective,sensitive,rapid and inexpensive.3.A untargeted plant metabolomics study of Asian and American ginsengIn order to understand the significant differences in activities and effects between Asian ginseng(ASG)and American ginseng(AMG),it is important to study chemical differentiations between the two types of herbs.However,more attention has been paid to the analysis of ginsenosides in previous reports distinguishing between ASG and AMG.There are some other bioactive compounds besides ginsenosides,however,few studies have focused on a systematic comparison of these types of compounds.Two metabolomic methods were developed in this study by qualitative data acquisition using hydrophilic interaction chromatography-mass spectrometry(HILIC-MS)and reverse phase liquid chromatographymass spectrometry(RPLC-MS)respectively,in combination with principal component analysis(PCA).Results show that both HILIC-MS and RPLC-MS-based plant metabolomic methods are feasible in composition profiling,biomarker screening as well as in discrimination of ASG and AMG.16 ginsenosides were identified as analytical markers in RPLC-MS-based plant metabolomic method.In comparison,using HILIC-MS-based method,5 ginsenosides,3 amino acids as well as 1 oligosaccharide were identified as analytical markers.Therefore,RPLC-MS-based plant metabolomic method exhibits better profiling in ginsenosides,while HILIC-MS-based plant metabolomic method offers the advantage that multiple active ingredients can be determined simultaneously.The two methods are both helpful in identification of analytical markers as well as in discrimination of American ginsengs from Asian ginsengs.4.Analysis of oligosaccharides from Panax ginseng by using solid-phase permethylation method combined with plant metabolomicsThere is an urgent need to develop a practical procedure to detect and analyze ginseng oligosaccharides.The oligosaccharide extracts from ginseng were permethylated by solidphase methylation method and then were analyzed by ultra-high-performance liquid chromatography-Q-Orbitrap/MS.The sequence,linkage,and configuration information of oligosaccharides were determined by using accurate m/z value and tandem mass information.Several standard references were used to further confirm the identification.The oligosaccharide composition in white ginseng and red ginseng was compared using a multivariate statistical analysis method.The nonreducing oligosaccharide erlose among 12 oligosaccharides identified was reported for the first time in ginseng.In the comparison of the oligosaccharide extracts from white ginseng and red ginseng,a clear separation was observed in the partial least squares-discriminate analysis score plot,indicating the sugar differences in these two kinds of ginseng samples.The glycans with variable importance in the projection value large than 1.0 were considered to contribute most to the classification.The contents of oligosaccharides in red ginseng were lower than those in white ginseng,and the contents of maltose,maltotriose,maltotetraose,maltopentaose,maltohexaose,maltoheptaose,maltooctaose,maltononaose,sucrose,and erlose decreased significantly(p < 0.05)in red ginseng.