Quantitative determination of bioactive alkaloids lysergol and chanoclavine in Ipomoea muricata by reversed-phase high-performance liquid chromatography

A rapid, simple, sensitive, gradient and reproducible, reverse‐phase high‐performance liquid chromatographic method was developed for the quantitative estimation of bioactive alkaloids, lysergol and chanoclavine in the seeds of Ipomoea muricata. The clavine alkaloid, lysergol, is a bioenhancer for the drugs and nutrients. The samples were analyzed by reverse‐phase chromatography on a Waters spherisorb ODS2 column (250 × 4.6 mm, i.d., 10 µm) using binary gradient elution with acetonitrile and 0.01 m phosphate buffer (NaH₂PO₄) containing 0.1% glacial acetic acid at a flow rate of 0.8 mL/min, a column temperature of 25 °C and UV detection at λ 254 nm. The limits of detection (LOD) and quantitation (LOQ) were 0.035 and 0.106 µg/mL for lysergol and 0.039 and 0.118 µg/mL for chanoclavine, respectively. Standard curves were linear in the range of 2–10 µg/mL (r > 99) for both analytes. Good results were achieved with respect to repeatability (RSD < 2%) and recovery (99.20–102.0). The method was validated for linearity, accuracy repeatability, LOQ and LOD. The method is simple, accurate and precise, and may be recommended for routine quality control analysis of I. muricata seed extracts containing these two clavine alkaloids (1, 2) as bioactive principles of the herb. Copyright © 2011 John Wiley & Sons, Ltd.     

Simultaneous quantification of berberine and lysergol by HPLC-UV: evidence that lysergol enhances the oral bioavailability of berberine in rats

A sensitive and simple HPLC method was developed for the simultaneous quantification of berberine and lysergol in rat plasma. The chromatographic separation was achieved on a C₁₈ column using isocratic elution with methanol–acetonitrile–0.1% ortho‐phosphoric acid (25:20:55, v/v/v), pH adjusted to 6.5 with triethylamine and detected at a UV wavelength of 230 nm. The extraction of the berberine and lysergol from the rat plasma with methylene chloride resulted in their high recoveries (82.62 and 90.17%). HPLC calibration curves for both berberine and lysergol based on the extracts from the rat plasma were linear over a broad concentration range of 50–1000 ng/mL. The limit of quantification was 50 ng/mL. Intra‐ and inter‐day precisions were <15% and accuracy was 87.12–92.55% for berberine and 87.01–92.26% for lysergol. Stability studies showed that berberine and lysergol were stable in rat plasma for short‐ and long‐term period for sample preparation and analysis. The described method was successfully applied to study the pharmacokinetics of berberine as well as lysergol following oral administration in Sprague–Dawley rats. The results of the study inferred that lysergol improved the oral bioavailability of berberine. Copyright © 2011 John Wiley & Sons, Ltd.     

Theoretical and experimental studies on solubility and reactivity behavior of lysergol,elymoclavine, and dihydrolysergol

Lysergol, elymoclavine (Δ^9,10 and Δ^8,9 regioisomers), and dihydrolysergol are important members of ergolines. The present work reports their comparative study in gas and solvent phase (water) that has been performed both experimentally and theoretically. Theortical calculations have been carried within the density functional theory formalism to analyze the structural and electronic properties of these molecules with B3LYP hybrid exchange–correlational fuctional in conjunction with 6‐311++G (d,p) basis set. Hessian calculations are performed at B3LYP/6‐31G (d,p) level of theory in gas phase as well as other solvent phases. Solvent phase calculations are performed using Onsager reaction field model as implemented in Gaussian 03. A good agreement has been found between experimental and theoretical infrared and nuclear magnetic resonance (NMR) spectra. The calculated NMR data has been analyzed statistically. Stability of these regioisomers has been analyzed in terms of the energy gap between highest occupied molecular orbital and lowest unoccupied molecular orbital (HOMO–LUMO gap). Calculations for lysergol and elymoclavine in water as solvent were carried to examine the effect of solvent on the HOMO–LUMO levels and energy of these molecules. © 2012 Wiley Periodicals, Inc.