Monoterpenoids from Paeoniae Radix Rubra based on UPLC-Q-TOF-MS / 中国中药杂志

The ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used to conduct the qualitative analysis of the monoterpene chemical components from Paeoniae Radix Rubra. Gradient elution was performed on C_(18) HD(2.1 mm×100 mm, 2.5 μm) column with a mobile phase of 0.1% formic acid(A) and acetonitrile(B). The flow rate was 0.4 mL·min~(-1) and the column temperature was 30 ℃. MS analysis was conducted in both positive and negative ionization modes using electrospray ionization(ESI) source. Qualitative Analysis 10.0 was used for data processing. The identification of chemical components was realized by the combination of standard compounds, fragmentation patterns, and mass spectra data reported in the literature. Forty-one monoterpenoids in Paeoniae Radix Rubra extract were identified. Among them, 8 compounds were reported in Paeoniae Radix Rubra for the first time and 1 was presumed to be the new compound 5″-O-methyl-galloylpaeoniflorin or its positional isomer. The method in this study realizes the rapid identification of monoterpenoids from Paeoniae Radix Rubra and provides a material and scientific basis for quality control and further study on the pharmaceutical effect of Paeoniae Radix Rubra.

Investigation of modulating effect of Qingfei Paidu Decoction on host metabolism and gut microbiome in rats / 中国中药杂志

This study is to explore the effect of Qingfei Paidu Decoction(QPD) on the host metabolism and gut microbiome of rats with metabolomics and 16 S rDNA sequencing. Based on 16 S rDNA sequencing of gut microbiome and metabolomics(GC-MS and LC-MS/MS), we systematically studied the serum metabolites profile and gut microbiota composition of rats treated with QPD for continued 5 days by oral gavage. A total of 23 and 43 differential metabolites were identified based on QPD with GC-MS and LC-MS/MS, respectively. The involved metabolic pathways of these differential metabolites included glycerophospholipid metabolism, linoleic acid metabolism, TCA cycle and pyruvate metabolism. Meanwhile, we found that QPD significantly regulated the composition of gut microbiota in rats, such as enriched Romboutsia, Turicibacter, and Clostridium_sensu_stricto_1, and decreased norank_f_Lachnospiraceae. Our current study indicated that short-term intervention of QPD could significantly regulate the host metabolism and gut microbiota composition of rats dose-dependently, suggesting that the clinical efficacy of QPD may be related with the regulation on host metabolism and gut microbiome.

Study of Intermolecular Interactions Between Pterostilbene and Human Serum Albumin by Fluorescence Spectrometry-Surface Enhanced Raman Spectroscopy / 分析化学

The binding mechanism between pterostilbene ( PTE) and human serum albumin ( HSA) was investigated by fluorescence spectrometry and surface enhanced Raman spectroscopy (SERS) under simulated physiological conditions. The experiment result showed that the effect between PTE and HSA was a static fluorescence quenching with F?rsterˊ s non-radioactive energy transformation, and PTE could bind HSA strongly with a 1: 1 molar ratio. The binding distances between PTE and HSA was 1. 495 nm, and the binding constants (KA) between PTE and HSA were 1. 12 × 104 (298 K), 4. 07 × 104 (304 K) and 2. 45 × 105 L/ mol (310 K). SERS revealed that PTE combined with HAS by methoxy group. Thermodynamic data indicated that the interaction between PTE and HSA was mainly hydrophobic interaction. Marker competition experiments pointed out that the primary binding site for PTE was located at site Ⅲ in HSA. Three-dimensional, synchronous fluorescence spectrum and SERS showed that the conformation of HSA changed apparently with the addition of PTE, resulting in the tryptophan residue of HSA exposing to a less hydrophobic micro-environment. However, the conformation of PTE did not change apparently with the addition of HSA.