harpagide and catalpol

An improved high-performance liquid chromatography with diode array detection combined with accelerated solvent extraction method was used to simultaneously determine six compounds in crude and processed Radix Scrophulariae samples. Accelerated solvent extraction parameters such as extraction solvent, temperature, number of cycles, and analysis procedure were systematically optimized. The results indicated that compared with crude Radix Scrophulariae samples, the processed samples had lower contents of harpagide and harpagoside but higher contents of catalpol, acteoside, angoroside C, and cinnamic acid. The established method was sufficiently rapid and reliable for the global quality evaluation of crude and processed herbal medicines.

Topics: Chromatography, High Pressure Liquid; Cinnamates; Coumaric Acids; Glucosides; Glycosides; Iridoid Glucosides; Iridoid Glycosides; Phenols; Pyrans; Quality Control; Scrophularia; Solvents; Trisaccharides

To enable an investigation of pharmacokinetics and tissue distribution of Aucubin, Ajugol and Catalpol in rats, a high-performance liquid chromatography-electro spray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method was developed for the simultaneous quantitative determination of the three compounds. Biological samples were prepared by a simple protein precipitation with methanol (containing 0.05% formic acid). The analytes were separated by a C18 reversed phase column and detected with a triple quadrupole tandem mass spectrometer in the multiple-reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z 364.3→149.0 for Aucubin, m/z 366.5→151.1 for Ajugol, m/z 380.0→183.3 for Catalpol and m/z 530.3→183.1 for Picroside-II (IS) in positive ionization. Good linearity of each calibration curve was produced over the concentration range of 1-1000ng/mL. The lower limit of quantification (LLOQ) was 1ng/mL for the three analytes. This method was successfully applied to the pharmacokinetic and tissue distribution studies of Aucubin, Ajugol and Catalpol in rat. The current results revealed pharmacokinetic behaviors of the herb compound and provided novel evidence of the presence of Aucubin and Catalpol in rat brain. The acquired data would be helpful for the clinical application and further studies of Traditional Chinese Medicines (TCM) with active ingredients of Iridoid Glycosides.

Topics: Animals; Chromatography, High Pressure Liquid; Female; Iridoid Glucosides; Iridoid Glycosides; Limit of Detection; Male; Pyrans; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Tissue Distribution

A simple and efficient liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for simultaneous quantitation of catalpol and harpagide in normal and diabetic rat plasma. Protein precipitation extraction with acetonitrile was carried out using salidroside as the internal standard (IS). The LC separation was performed on an Elite C18 column (150 × 4.6 mm, 5 µm) with the mobile phase consisting of acetonitrile and water within a runtime of 12.0 min. The analytes were detected without endogenous interference in the selected ion monitoring mode with positive electrospray ionization. Calibration curves offered satisfactory linearity (r > 0.99) at linear range of 0.05-50.0 µg/mL for catalpol and 0.025-5.0 µg/mL for harpagide with the lower limits of quantitation of 0.05 and 0.025 µg/mL, respectively. Intra- and inter-day precisions (RSD) were <9.4%, and accuracy (RE) was in the -6.6 to 4.9% range. The extraction efficiencies of catalpol, harpagide and IS were all >76.5% and the matrix effects of the analytes ranged from 86.5 to 106.0%. The method was successfully applied to the pharmacokinetic study of catalpol and harpagide after oral administration of Zeng-Ye-Decoction to normal and diabetic rats, respectively.

Topics: Animals; Chromatography, Liquid; Diabetes Mellitus, Experimental; Drugs, Chinese Herbal; Hypoglycemic Agents; Iridoid Glucosides; Iridoid Glycosides; Limit of Detection; Male; Mass Spectrometry; Pyrans; Rats; Rats, Sprague-Dawley

In this paper, absorption and pharmacokinetic study of Radix Rehmanniae was studied by liquid chromatography coupled with mass spectrometry method after oral administration to rats. By comparing the chromatograms of ultraviolet, full scan, extracted ion and selective reaction monitoring (SRM) of standard solution, Radix Rehmanniae, blank plasma and rat plasma post drug administration, catalpol and ajugol were found to be the main compounds absorbed from Radix Rehmanniae. Plasma concentrations of aucubin, dihydrocatalpol, rehmannioside A (or rehmannioside B/ melittoside) and rehmannioside D were very low. Quantitative method for catalpol and aucubin and semi-quantitative method for other compounds in rat plasma were established. The pharmacokinetic study of those absorbed components was conducted after oral administration of 6 g x kg(-1) Radix Rehmanniae water extract to rats. Cmax, t(1/2) and AUC(0-infinity) of catalpol and ajugol were (2349.05 +/- 1438.34) and (104.25 +/- 82.05) ng x mL(-1), (0.86 +/- 0.32) and (0.96 +/- 0.37) h, (4407.58 +/- 2734.89) and (226.66 +/- 188.38) ng x h x mL(-1), respectively. tmax was at 1.00 h for catalpol and ajugol. Both catalpol and ajugol were absorbed and excreted rapidly.

Topics: Administration, Oral; Animals; Area Under Curve; Drugs, Chinese Herbal; Female; Iridoid Glucosides; Iridoid Glycosides; Male; Molecular Structure; Plant Roots; Plants, Medicinal; Pyrans; Rats; Rats, Sprague-Dawley; Rehmannia

Growth inhibitory activities and nutritional indices of catalpol (1), 8-O-acetylharpagide (2), and harpagide (3) were determinated in larvae and adults of Tribolium castaneum, respectively. Compound 1 produced a series of allelochemical effects probably related with the DNA synthesis. This iridoid possessed the highest inhibitory activity against DNA polymerase. Molecular orbital calculations suggest that a pi-pi charge transfer recognition model could explain the action of iridioids toward nucleic acid synthesis.

Topics: Animals; Enzyme Inhibitors; Glucosides; Insect Control; Iridoid Glucosides; Iridoid Glycosides; Iridoids; Larva; Models, Molecular; Molecular Structure; Nucleic Acid Synthesis Inhibitors; Pyrans; Tribolium