Analysis Of Diarylheptanoids In Alpinia Officinarum By UPLC/Q-TOF MS And Study On Anti-inflammatory Activity Of Monomer

Alpinia officinarum Hance (Zingiberaceae) is a medicinal herb native to East Asia. Its dried rhizomes are used as stomachic, analgetic, and antiemetic.Natural diarylheptanoids which are widely distributed in the Zingberaceae, have been reported to possess anti-inflammatory, antiplatelet, analgesic, antioxidant, and antiproliferative activities. In recent years, it has become a hot point people studied.In the present study, GC-MS and HPLC-MS have been used to analyze the diarylheptenoids and flavonoids in Alpinia officinarum. The results indicate that GC-MS can not be used to determine these compounds due to their low volatility and thermally labile properties. LC/MS could be used to determine these compounds and provide fast and accurate analysis as an on-line technique. So LC/MS method was successfully established to characterize diarylheptenoids and flavonoids in the supercutical fluid extract of Alpinia officinarum. The method established provided good reproducibility of UPLC and showed high precision with all the mass accuracy of less than 5 ppm. On the basis of analyzing the fragmentation pathways in both positive and negative modes,elemental compositions provided by software Masslynx, mass data of the standard compounds and the information regarding polarity obtained from retention time data, We characterized the diarylheptanoids and flavonoids in supercutical fluid extract of Alpinia officinarum using UPLC-Q-TOF MS/MS in both positive mode and negative mode. Six distinct groups (homologous series) of diarylheptanoids were found in Alpinia officinarum. These groups were differentiated by structural differences on the heptane skeletons, whereas homologs within each group differed by substitution patterns on the aromatic rings. Diagnostic fragmentation behavior in ESI-MS/MS analyses for each group of homologs, as well as information regarding polarity obtained from retention time data, allowed us to classify these compounds by group and identify them based on key structural features. In all, 23 diarylheptanoids and eight flavonoids were identified from the extract. We alse characterized 8 flavonoids, three flavonoids were unreported in this plant before.Three diarylheptanoids has been prepared by using the half-prep HPLC. They were characterized to be 5-hydroxy-1-phenyl-7- (4-hydroxy-3-methoxylphenyl) -3-heptanone, 5-hydroxy-1,7-bisphenyl-3-heptanone, 1,7-bisphenyl-4-en-3-heptanone respectively. The antiinflammatory mechanism on RAW264.7 cells of 5-hydroxy-1-phenyl-7- (4-hydroxy-3-methoxylphenyl)-3-heptanone was studied and the results shown that this compound is a potential COX-2 inhabitor.