Chemical profiling from water extract of Wikstroemia indica by UPLC-Q-TOF-MS/MS / 中国中药杂志

In this study,a method using ultra performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry( UPLC-Q-TOF-MS/MS) was established to identify complicated chemical constituents of Wikstroemia indica. Chromatographic separation was performed on an AcclaimTMRSLC 120-C18 column( 2. 1 mm×100 mm,2. 2 μm) using gradient elution with 0. 2% ammonium formate buffer salt solution( A)-0. 2% ammonium formate buffer salt solution methanol( B) as mobile phase. The column temperature was maintained at 30 ℃. The analytes were determined by positive and negative ion modes with electro-spray ionization source. A total of 52 compounds( including eleven coumarins,thirteen flavonoids,ten lignans,two amides,four phenolic acids,six sesquiterpenes and six other compounds) were identified or tentatively characterized from the water extract of W. indica by comparing their retention times and MS spectra with those of authentic standards or literature datas. Three compounds were found for the first time from W.indica namely isomer of indicanone,β-hydroxypropiovanillone and epiprocurcumenol. Furthermore,the fragmentation rules of some compounds were speculated and summarized. In addition,the cleavage pathways of guaiane sesquiterpenes were described for the first time,which can provide reference for studying the fragmentation pathways of similar compounds. This study provides an easy way to identify chemical constituents of traditional Chinese medicine and a basis for the further study on chemical fundamentals of W. indica.

Mechanism research of curcumin on cancer cells based on cell metabolic profiling / 中国中药杂志

In this study, gas chromatography coupled with mass spectrometry(GC-MS) was used to analyze the changes of 12 kinds of cancer cells treated by curcumin. The related differential metabolites were screened and the metabolic pathways were analyzed to explore the anti-tumor mechanism of curcumin. Methyl thiazol tetrazolium(MTT) assay was used to detect the 50% inhibiting concentration(IC_(50)) of curcumin on 12 human tumor cells. After treatment with curcumin for 48 h, the cells were collected and analyzed by GC-MS, followed by pathway analysis and multivariate data analysis including principal component analysis(PCA), orthogonal partial least squares discriminant analysis(OPLS-DA) and One-way analysis of variance(ANOVA),etc. Overall, 34 metabolites showed significant concentration changes after intervention for 48 h, mainly involving multiple metabolic pathways, including lysine degradation, glycine, serine and threonine metabolism, arginine and proline metabolism, cysteine and methionine metabolism, aminoacyl-tRNA biosynthesis, primary bile acid biosynthesis, lysine biosynthesis. In this study, the anti-tumor mechanisms of curcumin interfering with energy metabolism, amino acid metabolism, microtubule system, protein synthesis and oxidative stress response of tumor cells were analyzed from the perspective of metabolism, providing a new reference for further tumor pharmacology study.