hydroxygenkwanin and genkwanin

Hydroxygenkwanin (HYGN) and genkwanin (GN) are major constituents of Genkwa Flos for the treatment of edema, ascites, cough, asthma and cancer. This is a report about the investigation of the metabolic fate of HYGN and GN in human liver microsomes and the recombinant UDP-glucuronosyltransferase (UGT) enzymes by using ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). An on-line data acquisition method multiple mass defect filter (MMDF) combined with dynamic background subtraction (DBS) was developed to trace all probable metabolites. Based on this analytical strategy, three phase I metabolites and seven glucuronide conjugation metabolites of HYGN, seven phase I metabolites and 12 glucuronide conjugation metabolites of GN were identified in the incubation samples of human liver microsomes. The results indicated that demethylation, hydroxylation and o-glucuronidation were main metabolic pathways of HYGN and GN. The specific UGT enzymes responsible for HYGN and GN glucuronidation metabolites were identified using recombinant UGT enzymes. The results indicated that UGT1A1, UGT1A3, UGT1A9, UGT1A10 and UGT2B7 might play major roles in the glucuronidation reactions. Overall, this study may be useful for the investigation of metabolic mechanism of HYGN and GN, and it can provide reference and evidence for further experiments.

Topics: Chromatography, High Pressure Liquid; Flavones; Flavonoids; Glucuronosyltransferase; Humans; Microsomes, Liver; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

A sensitive UHPLC-MS/MS approach was developed and validated for the quantification of genkwanin, 3'-hydroxygenkwanin, apigenin, luteolin, yuanhuacine and genkwadaphnin in biological samples after oral administration of raw and vinegar-processed Daphne genkwa. Liquiritin and glycyrrhetinic acid were employed as internal standards. Six components were extracted by using protein precipitation with acetonitrile. Chromatographic separation was achieved on a Waters BEH C

Topics: Acetic Acid; Administration, Oral; Animals; Apigenin; Biological Availability; Daphne; Diterpenes; Flavones; Flavonoids; Liquid-Liquid Extraction; Male; Plant Extracts; Plant Roots; Rats, Sprague-Dawley; Tandem Mass Spectrometry; Water

To predict the mechanism of liver injury induced by Genkwa Flos, we investigated the effect of chloroform extract on UGTs and UGT1A1 activities of the liver microsomes in rat and human. In the present study, 4-nitrophenol(4-NP) and β-estradiol were elected as substrates to determine activities of UGTs and UGT1A1 by UV and HPLC. The results showed that there were 1.00% of apigenin, 6.40% of hydroxygenkwanin and 18.38% of genkwanin in chloroform extract; and total diterpene mass fraction was 31.40%. Compared with the control group, chloroform extract could significantly inhibit the activity of UGTs in rat liver microsomes(RLM) system, while the inhibitory effect was not obvious in human liver microsomes(HLM) system. UGT1A1 activity was inhibited by chloroform extract in rat liver microsomes and human liver microsomes (based on genkwanin, IC₅₀=8.76, 10.36 μmol•L⁻¹). The inhibition types were non-competitive inhibition(RLM) and uncompetitive inhibition(HLM). In conclusion, the results indicated that chloroform extract showed different inhibitory effects on UGTs and UGT1A1 activity, which may be one of the mechanisms of liver injury induced by Genkwa Flos.

Topics: Animals; Apigenin; Chromatography, High Pressure Liquid; Daphne; Drugs, Chinese Herbal; Estradiol; Flavones; Flavonoids; Glucuronosyltransferase; Humans; Microsomes, Liver; Nitrophenols; Plant Extracts; Rats

To improve the traditional fingerprint method to distinguish vinegar processed Genkwa Flos from raw Genkwa Flos.. Ten batches of Genkwa Flos were collected, processed with vinegar through a standard method, and then analyzed under the optimum HPLC condition. Based on the chromatographic data obtained, a common model of vinegar processed Genkwa Flos fingerprints, including 11 common peaks and the components genkwanin, hydroxygenkwanin, luteolin, apigenin and yuanhuacin were identified, was established. The peak of baicalein, an exogenous component added quantitatively to the samples as an internal standard, was served as the reference peak. The similarity between the test samples and the common model was computed using the improved Euclidean distance method developed in this paper.. The similarities between vinegar processed Genkwa Flos samples and the common model were higher than 0.9, whereas those between raw Genkwa Flos and the common model were lower than 0.9.. The proposed method thus effectively provides a clear distinction between vinegar processed and raw Genkwa Flos samples. The result is helpful to ensure the safe clinical use of the plant and expand the application field of fingerprinting technology.

Topics: Acetic Acid; Apigenin; Chromatography, High Pressure Liquid; Daphne; Diterpenes; Drugs, Chinese Herbal; Flavones; Flavonoids; Flowers; Luteolin

To research the chemical constituents from Daphne tangutica.. Column chromatography with silica gel, ODS-C18, Sephadex LH-20 and re-crystallization were employed to isolate and purify the constituents. According to physical and chemical properties and spectral data to identify the structure of compounds.. Eight compounds were isolated and identified as palmitic acid (1), laurostearic acid(2), beta-sitosterol(3), 7-methoxy-8-hydroxycumarin(4), daphnetin(5), genkwanin(6), hydroxygenkwanin(7), p-hydroxybenzoic acid(8).. Compounds 1,2,7 and 8 are isolated from Daphne tangutica for the first time.

Topics: Daphne; Flavones; Flavonoids; Magnetic Resonance Spectroscopy; Palmitic Acid; Parabens; Plant Bark; Plants, Medicinal; Sitosterols

Thin-layer chromatography and a dual wavelength TLC-scanner (Shimadzu CS-910) were used for the determination of hydroxygenkwanin and genkwanin in flos Genkwa before and after processing with vinegar. The result shows that the amounts of hydroxygenkwanin and genkwanin in processed products were increased. The amounts of the said two constituents were different in various products.

Topics: Chromatography, Thin Layer; Drugs, Chinese Herbal; Flavones; Flavonoids; Hot Temperature; Technology, Pharmaceutical