RESUMO
Saponaria officinalis L. (Caryophyllaceae), also known as fuller's herb or soapwort is a medicinal plant, which grows from Europe to Central Asia. Medicinal properties attributed to this plant include its antitussive and galactogogue properties. Recently, bisdesmodic saponins with very specific structural features from S. officinalis have been shown to strongly enhance the efficacy of specific targeted toxins (anti-tumor antibodies connected to protein toxins) in-vitro and in-vivo in a synergistic manner. In the presently reported novel approach we used preparative all-liquid high-speed countercurrent chromatography (HSCCC) to recover a total of 22 fractions using biphasic solvent system tert-butylmethylether/n-butanol/acetonitrile/water 1:3:1:5 (v/v/v/v) from a complex precipitated crude saponin mixture. Out of these 22 fractions, 3 fractions had the enhancer effect on anti-tumor toxins out of which one fraction (F7) was further tested elaborately in different cell lines. The molecular weight distribution and compound profiles of separated saponins were monitored by off-line injections of the sequentially collected fractions to an electrospray ion-trap mass-spectrometry system (ESI-IT-MS). The functional saponin fractions were mainly bisdesmosidc and contained saponin m/z 1861 amongst other. Using the bio-assay guided monitoring, the highly active fractions containing 2 to 3 bisdesmodic saponins (5µg/mL) were screened for their effectiveness in enhancing the anti-tumor activity of targeted toxin Sap3-EGF, which was determined using the impedance based real-time cell cytotoxicity evaluation. This novel combination of HSCCC fractionation, MS-target-guided profiling procedure and bio-assay guided fractionation yielded 100mg of functional saponins from a 60g crude drug powder in a rapid and convenient manner.
Assuntos
Distribuição Contracorrente/métodos , Extratos Vegetais/química , Saponaria/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Antineoplásicos , Sinergismo Farmacológico , Imunotoxinas , Saponinas/análise , Saponinas/química , Saponinas/isolamento & purificaçãoRESUMO
Single-crystal X-ray diffraction and high-resolution (1)H and (13)C NMR spectral data for methyl 6-deoxy-6-iodo-alpha-D-glucopyranoside are reported. The (4)C(1) conformation was found to be the preferred form for this compound, both in the crystal lattice and in solution. The rotational preferences of all the groups bound to the pyranose ring are presented. The stabilization of the crystal structure by a network of O-H...O intra- and intermolecular interactions as well as the short contacts of the iodine atoms is discussed.