lignans and isoquercitrin

Fructus Gardeniae-Fructus Forsythiae herb pair is an herbal formula used extensively to treat inflammation and fever, but few systematic identification studies of the bioactive components have been reported. Herein, the unknown analogues in the first-step screening were rapidly identified from representative compounds in different structure types (geniposide as iridoid type, crocetin as crocetin type, jasminoside B as monocyclic monoterpene type, oleanolic acid as saponin type, 3-caffeoylquinic acid as organic acid type, forsythoside A as phenylethanoid type, phillyrin as lignan type and quercetin 3-rutinoside as flavonoid type) by UPLC-Q-Tof/MS combined with mass defect filtering (MDF), and further confirmed with reference standards and published literatures. Similarly, in the second step, other unknown components were rapidly discovered from the compounds identified in the first step by MDF. Using the two-step screening method, a total of 58 components were characterized in Fructus Gardeniae-Fructus Forsythiae (FG-FF) decoction. In rat's blood, 36 compounds in extract and 16 metabolites were unambiguously or tentatively identified. Besides, we found the principal metabolites were glucuronide conjugates, with the glucuronide conjugates of caffeic acid, quercetin and kaempferol confirmed as caffeic acid 3-glucuronide, quercetin 3-glucuronide and kaempferol 3-glucuronide by reference standards, respectively. Additionally, most of them bound more strongly to human serum albumin than their respective prototypes, predicted by Molecular Docking and Simulation, indicating that they had lower blood clearance in vivo and possibly more contribution to pharmacological effects. This study developed a novel two-step screening method in addressing how to comprehensively screen components in herbal medicine by UPLC-Q-Tof/MS with MDF.

Topics: Animals; Binding Sites; Chromatography, High Pressure Liquid; Drugs, Chinese Herbal; Fruit; Gardenia; Glucuronides; Glycosides; Humans; Lignans; Male; Molecular Docking Simulation; Plant Extracts; Quercetin; Rats; Rats, Sprague-Dawley; Serum Albumin; Solid Phase Extraction; Tandem Mass Spectrometry

The high-performance liquid chromatography fingerprint method is a simple and reliable technique to evaluate the quality of leaves of Magnolia officinalis Rehd.et Wils. var. biloba Rehd.et Wils. We used the following bioactive phenolic constituents as reference compounds: rutin, afzelin, hyperoside, isoquercitrin, quercetin-3-O-α-l-rhamnoside, honokiol and magnolol. The conditions of an Agilent 1200 HPLC were: YMC-Pack-ODS-AQ column (250 × 4.6 mm id S-5 μm, 12 nm), mobile phase acetonitrile and 0.2% phosphoric acid in a gradient elute mode, flow rate 1.0 mL/min, detection wavelength 280 nm and column temperature 30°C. The analytical method was validated in terms of linearity, stability, repeatability, precision and recovery tests. While performing fingerprint analysis, we identified 11 peaks as characteristic peaks and assessed the similarities of 17 samples collected from different geological regions of China. The peak areas were used to evaluate the variation in the chemical composition of the tested samples. For this purpose, we performed hierarchical cluster analysis of the peak areas. Our results indicate that simultaneous determination of multiple ingredients could be done through chromatographic fingerprint analysis. Therefore, this high-performance liquid chromatography fingerprint method was readily utilized to evaluate the quality of leaves of M. officinalis var.biloba, which are used in several traditional herbal preparations.

Topics: Biphenyl Compounds; China; Chromatography; Chromatography, High Pressure Liquid; Glucosides; Lignans; Magnolia; Mannosides; Phenols; Plant Extracts; Plant Leaves; Proanthocyanidins; Quercetin; Reference Values; Reproducibility of Results; Rutin; Temperature