stilbenes and icariin

To develop a qualitative and quantitative determination of multiple components for quality control of Hugu Capsule, a composite prescription in TCM.. HPLC analysis was performed on a Kromasil C18 column (5.0 microm, 250 mm x 4.6 mm) by gradient elution with methanol-acetonitrile-1% glacial acetic acid as the mobile phase at a flow-rate of 0.8 mL/min,the detection wavelengths were set at 270, 283, 320 and 325 nm at the temperature of 30 degrees C.. Five components: chlorogenic acid, tetrahydroxy stilbene glucoside, ferulaic acid, naringin and icariin were simultaneously analyzed in this study. The calibration curves were exhibited linear regressions of at least r > 0.9992. The injection precision,the intra-day precisions and the analysis repeatability were evaluated with the RSD values were all less than 5%. The mean recoveries of the five components were ranged from 97.4% to 99.4%, and RSD values all were less than 1.72%.. This method is found to be convenient, fast, accurate, and is applicable to analyze the multi-constituents in Hugu Capsule.

Topics: Capsules; Chlorogenic Acid; Chromatography, High Pressure Liquid; Coumaric Acids; Drug Combinations; Drugs, Chinese Herbal; Flavanones; Flavonoids; Glucosides; Quality Control; Reproducibility of Results; Stilbenes

Propionibacterium acnes is a Gram-positive bacterium that plays an important role in the pathogenesis of acne vulgaris. This organism is capable of biofilm formation and the decreased antimicrobial susceptibility of biofilm-associated cells may hamper efficient treatment. In addition, the prolonged use of systemic antibiotic therapy is likely to lead to the development and spread of antimicrobial resistance. In the present study we investigated whether P. acnes biofilms could be eradicated by plant extracts or their active compounds, and whether other mechanisms besides killing of biofilm cells could be involved. Out of 119 plant extracts investigated, we identified five with potent antibiofilm activity against P. acnes (extracts from Epimedium brevicornum, Malus pumila, Polygonum cuspidatum, Rhodiola crenulata and Dolichos lablab). We subsequently identified icariin, resveratrol and salidroside as active compounds in three of these extracts. Extracts from E. brevicornum and P. cuspidatum, as well as their active compounds (icariin and resveratrol, respectively) showed marked antibiofilm activity when used in subinhibitory concentrations, indicating that killing of microbial cells is not their only mode of action.

Topics: Acne Vulgaris; Biofilms; Dolichos; Drug Resistance, Bacterial; Epimedium; Flavonoids; Fruit; Glucosides; Humans; Malus; Microbial Sensitivity Tests; Phenols; Plant Extracts; Plant Roots; Polygonum; Propionibacterium acnes; Resveratrol; Rhizome; Rhodiola; Sebaceous Glands; Seeds; Stilbenes