Chemical constituents from the seeds of Cassia obtusefolia and their in vitro α-glucosidase inhibitory and antioxidant activities.

Basing on chromatographic separation techniques, fifteen aglycones (1-15), including two new anthraquinone aglycones (1, 2) and thirteen known compounds (3-15), were isolated from the small polar fraction of Cassia obtusefolia (petroleum ether extract). Structural elucidations were performed by 1D/2D NMR spectroscopy and mass spectrometry. The in vitro antioxidant and α-glucosidase inhibitory activities of these fifteen compounds were determined. Except compounds 12 (IC50 3.03 ±â€¯0.31 µg/mL, stronger than ascorbic acid, which IC50 was 6.48 ±â€¯2.30 µg/mL) and 13 (IC50 78.40 ±â€¯2.39 µg/mL), the free radical scavenging capacities of other compounds were weak. Compounds 4, 5, 6 and 13 exhibited inhibitory activities on α-glucosidase with IC50 values of 50.60 ±â€¯1.10, 22.57 ±â€¯0.07, 60.09 ±â€¯1.40, and 80.01 ±â€¯2.66 µg/mL separately, however, all the α-glucosidase inhibitory activities were weaker than positive control (acarbose).

Pharmacokinetic comparisons of major bioactive components after oral administration of raw and steamed rhubarb by UPLC-MS/MS.

A study was performed to compare the pharmacokinetics of major bioactive analytes in rhubarb plants to explore the pharmacological differences between raw pieces (RP) and steamed pieces (SP) of rhubarb. A rapid and efficient ultra-performance liquid chromatographic coupled with mass/mass spectrometry (UPLC-MS/MS) method was established to determine the concentrations of six analytes in rat plasma after oral administration of RP and SP. It was found that the AUC (area under the plasma concentration-time curve), Tmax (time to reach maximum plasma concentration) and Cmax (maximum plasma concentration) values were obviously increased in RP for rhein-8-O-ß-d-glucophyranoside, rhein and aloe-emodin. On the contrary, emodin, physcion and chrysophanol had higher bioavailability in SP. The significant differences indicated that steamed by wine may alter pharmacokinetic behaviors of analytes, providing theoretical basis of differences in pharmacological activity between SP and RP.

In-Silico UHPLC Method Optimization for Aglycones in the Herbal Laxatives Aloe barbadensis Mill., Cassia angustifolia Vahl Pods, Rhamnus frangula L. Bark, Rhamnus purshianus DC. Bark, and Rheum palmatum L. Roots.

For the European Pharmacopoeia (Ph. Eur.) herbal monograph draft of Cassia angustifolia Vahl. and Cassia senna L. leaves and pods, a safety limitation of aloe-emodin and rhein was proposed, due to toxicological concerns. A quantitative, analytical method of the anthraquinone aglycones in all Ph. Eur. monographed herbal laxatives is of interest. A rational method development for the aglycones aloe-emodin, rhein, emodin, chrysophanol, and physcion in five herbal drugs was realized by using 3D chromatographic modelling (temperature, solvent, and gradient time) and design of experiment (DOE) software (DryLab® 4). A methodical approach suitable for the challenging peak tracking in the chromatograms of the herbal drugs in dependence on the changes in the chromatographic conditions is described by using a combination of mass spectroscopy (MS) data (UHPLC-QDa), UV/Vis-spectra, and peak areas. The model results indicate a low robust range and showed that with the selected chromatographic system, small interferences could not be averted. The separation achieved shows a pure UV/Vis spectrum for all aglycones except for chrysophanol in Aloe barbadensis and emodin in Cassia angustifolia fruit. A gradient with the best resolution of the aglycones in all five drugs is proposed, and its suitability demonstrated for the quantification of aglycones in these herbal drugs.

Investigation of orthogonal design of supercritical fluid extraction(SFE) for extracting anthraquinone aglycones from Rhubarb / 中成药

AIM: To optimize the extraction of the anthraquinone aglycnes from Rhubarb using supercritical fluid extraction(SFE). METHODS: Orthogonal design and variance analysis were used to optimize five operational variables of SFE. RESULTS: The optimized operational variables of SFE were obtained as following: the temperature was 70 ?C , the pressure was 35 MPa, the static extraction time was 8 min, the dynamic extraction volume 5 mL and methanol were used as modifier. CONCLUSION: SFE is rapid, convenient and accurate, and can be used to extract athraquinone aglycones from Rhubarb.

Determination of anthraquinone aglycones of Radix et Rhizome Rhei in Ganning Granule by HPLC / 中成药

AIM:To determine Radix et Rhizoma Rhici in Ganning Granula(Radix et Rhizoma Rhei,Rhizoma Chuanxiong). METHODS: In order to determine five anthraquinone aglycones of Radix et Rhizoma Rhei,the HPLC system consisted of Nucleosil ODS column,methand-0.1% phosphoric acid(85∶15) mixture as mobile phase,with detection wavelength at 430 nm. RESULTS: HPLC showed that the linearity ranges were as follows: aloe-emodin concentration was at the range of 0.041 6-0.291 2 ?g,the rhein concentration was at the range of 0.037 1-0.259 8 ?g,the emodin concentration was at the range of 0.045 8-0.320 3 ?g,the chrysophanol concentration was at the range of 0.049 60.347 2 ?g,the physcion concentration was at the range of 0.020 6-0.144 5 ?g.The average recoveries of five anthraquinone aglycones were between 96.6%-98.4%.CONCLUSION: The method is simple,accurate,sensible and with good repeatability and can be used for quality control of Ganning Granule.