Home About us Contact
|
Home About us Contact | ||
|
|
||
Compound K (compound + k)
Selected Abstracts20-O-,-D-Glucopyranosyl-20 (S)-protopanaxadiol (compound K) induces expression of hyaluronan synthase 2 gene in transformed human keratinocytes and fibroblasts and increases hyaluronan in hairless mouse skinINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2004S. Kim Ginsenosides, the major active ingredient of ginseng, show a variety of biomedical efficacies such as anti-aging, anti-oxidation and anti-inflammatory activities. To understand the effects of 20-O-,-D-glucopyranosyl-20 (S)-protopanaxadiol (compound K), one of the major metabolites of ginsenosides on the skin, we assessed the expression level of approximately 100 transcripts in compound K-treated HaCaT cells using cDNA microarray analysis. Compound K treatment induced differential expression of 40 genes, which have been reported to be involved in the organization of the structure of the extracellular matrix as well as defense responses in human skin cells. One of the most interesting findings is a two-fold increase in hyaluronan synthase2 (HAS2) gene expression by compound K. We found that change in expression of HAS2 gene represents a specific response of HaCaT cells to compound K because hyaluronan synthase 1,3 was not changed by treatment with compound K. We also demonstrated that the compound K effectively induced hyaluronan synthesis in human skin cells and hairless mouse skin. A human clinical study indicated that topical application of compound K containing oil-in-water emulsion showed improvement of xerosis, wrinkle and fine lines in the aged skin. We concluded that compound K has anti-aging effects by the induction of HAS2 gene expression and following hyaluronan synthase. [source] Comparative analysis on microbial and rat metabolism of ginsenoside Rb1 by high-performance liquid chromatography coupled with tandem mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 7 2008Guangtong Chen Abstract Ginsenoside Rb1 is an active protopanaxadiol saponin from Panax species. In order to compare the similarities and differences of microbial and mammalian metabolisms of ginsenoside Rb1, the microbial transformation by Acremonium strictum and metabolism in rats were comparatively studied. Microbial transformation of ginsenoside Rb1 by Acremonium strictum AS 3.2058 resulted in the formation of eight metabolites. Ten metabolites (M1,M10) were detected from the in vivo study in rats and eight of them were identified as the same compounds as those obtained from microbial metabolism by liquid chromatography,tandem mass spectrometry analysis and comparison with reference standards obtained from microbial metabolism. Their structures were identified as ginsenoside Rd, gypenoside XVII, 20(S)-ginsenoside Rg3, 20(R)-ginsenoside Rg3, ginsenoside F2, compound K, 12, -hydroxydammar-3-one-20(S) -O-, -d- glucopyranoside, and 25-hydroxyl-(E)-20(22)-ene-ginsenoside Rg3, respectively. The structures of the additional two metabolites were tentatively characterized as 20(22),24-diene-ginsenoside Rg3 and 25-hydroxyginsenoside Rd by HPLC-MS/MS analysis. M7,M10 are the first four reported metabolites in vivo. The time course of rat metabolism of ginsenoside Rb1 was also investigated. Copyright © 2008 John Wiley & Sons, Ltd. [source] Retention of arsenic species on zwitterionic stationary phase in hydrophilic interaction chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 6-7 2010Dan Xie Abstract Zwitterionic hydrophilic interaction chromatography (ZIC® -HILIC) was used to study the retention of selected organoarsenicals. The retention behavior of nine organic arsenic species on ZIC® -HILIC was investigated to elucidate which is the driving force for their separation, hydrophilic partitioning or adsorption driven by hydrogen bonds with surface H-donor/acceptor groups of the stationary phase. For this, the retention factor of the compounds k was correlated with log PO/W and with the calculated strength of hydrogen bonding of the analytes. By examining aliphatic and phenylic compounds separately, improved correlation was received. This indicates that both phenomena contribute to the separation of these arsenic species on ZIC® -HILIC. The results obtained evidence that considerable electrostatic interactions also occur on ZIC® -HILIC. Retention behavior of arsenic species was investigated by varying the separation conditions, which shows that the composition of the eluent has a strong influence on the retention behavior. It is highly dependent on water/acetonitrile ratio, pH value and salt additives. Dissociation degree and polarity of arsenic species, which are varying with pH, regulate the distribution of arsenic species between stationary and mobile phases in HILIC. Increase in the ammonium acetate concentration leads to shortened or to prolonged retention depending on the structure of the arsenic species. [source] | ||||||||||