Different Ways to On-Line Hyphenate Centrifugal Partition Chromatography and Mass Spectrometry: Application to Prenylated Xanthones from Garcinia mangostana.

Centrifugal partition chromatography is a liquid-liquid separation method well adapted for the fractionation or purification of natural compounds from plant extracts. However, following the preparative isolation, the fractions collected must be analysed by high-performance thin-layer chromatography or high-performance liquid chromatography to evaluate their composition and/or their purity. These additional steps are time-consuming and increase the risk of compound degradation. In order to get an instantaneous analysis of fraction content with structural information on the phytochemicals eluted, it is possible to hyphenate on-line centrifugal partition chromatography with mass spectrometry. Depending on the complexity of the extract, two different kinds of centrifugal partition chromatography-mass spectrometry coupling can be performed: centrifugal partition chromatography-mass spectrometry or centrifugal partition chromatography-high-performance liquid chromatography-mass spectrometry coupling. In the first case, one part of the centrifugal partition chromatography effluent is directly introduced in the mass spectrometry ionisation source to identify the eluted compounds, while in the second case, it is directed to a high-performance liquid chromatography-mass spectrometry system where compounds are first separated thanks to high-performance liquid chromatography and then identified using mass spectrometry.

Bioactive molecules in Kalanchoe pinnata leaves: extraction, purification, and identification.

Kalanchoe pinnata (Lam.) Pers. (syn. Bryophyllum pinnatum; family Crassulaceae) is a popular plant used in traditional medicine in many temperate regions of the world and particularly in South America. In Guyana, the leaves are traditionally used as an anti-inflammatory and antiseptic to treat coughs, ulcers, and sores. The purpose of this study was to implement a method for targeting and identifying molecules with antimicrobial activity, which could replace chemical preservatives in cosmetic applications. The leaves were extracted by a method based on pressurized liquid extraction (PLE), using different solvents. A study of antimicrobial activity and cytotoxicity tests were performed to select the most interesting extract. To isolate one or more active molecules, the selected crude extract was fractionated by centrifugal partition chromatography (CPC) and then antimicrobial activity and cytotoxicity of each fraction were tested under the same procedure. The last step consisted of identifying the main compounds in the most active fraction by LC-MS/MS.

Hyphenation of centrifugal partition chromatography with electrospray ionization mass spectrometry using an active flow-splitter device for characterization of flavonol glycosides.

Online coupling of centrifugal partition chromatography to electrospray ionization mass spectrometry (CPC/ESI-MS) was investigated for the separation and characterization of flavonol glycosides. Structural identification and purification monitoring of analytes on milligram scale were demonstrated to be possible by using an active flow-splitter device which transfers automatically and successively, at discrete frequencies, small aliquots of the chromatographic effluent to an independent auxiliary stream directed to an ESI quadrupole mass spectrometer. The CPC protocol used a biphasic solvent system composed of ethyl acetate/ethanol/water (4.5:1:4.5, v/v/v) in isocratic mode. During the separation process, continuous acquisition of mass spectral data of the isolated flavonols from the effluent was performed in the negative ion mode with an auxiliary stream composed of 50 mM ammonium acetate/ethanol (2:8, v/v) delivered by a secondary pump. To demonstrate the potential of this hyphenated technique, flavonol glycosides from an apple peel extract were identified, purified and quantitatively analyzed. Calibration curves and limits of detection are also detailed.

Strong ion-exchange centrifugal partition chromatography as an efficient method for the large-scale purification of glucosinolates.

The glucosinolates sinalbin and glucoraphanin were purified by strong ion-exchange displacement centrifugal partition chromatography (SIXCPC). The optimized conditions involved the biphasic solvent system ethyl acetate/n-butanol/water (3:2:5, v/v), the lipophilic anion-exchanger Aliquat 336 (trioctylmethylammonium chloride, 160 and 408 mM) and a sodium iodide solution (80 and 272 mM) as displacer. Amounts as high as 2.4 g of sinalbin and 2.6g of glucoraphanin were obtained in one step in 2.5 and 3.5h respectively, starting from 12 and 25 g of mustard and broccoli seed aqueous extracts, using a laboratory scale CPC column (200 mL inner volume).

Novel seco-dibenzopyrrocoline alkaloid from Cryptocarya oubatchensis.

[structure: see text] A novel seco-dibenzopyrrocoline alkaloid, named oubatchensine 6, and five phenanthroindolizidines (1-5) were isolated from Cryptocarya oubatchensis, and their structures were elucidated. Displacement centrifugal partition chromatography was used to purify compounds 1 and 6. Structure determination of the latter was carried out by mass spectrometry, NMR spectroscopy, quantum chemistry, and computer-assisted structure determination. Cytotoxic activity against KB cells was then investigated.