Fernanda Costa
Universidade Federal do Rio de Janeiro, Brazil
Title: Solvent System Selectivities in Countercurrent Chromatography Using Salicornia gaudichaudiana Metabolites as Practical Example with Off-line Electrospray Mass-Spectrometry Injection Profiling
Biography
Biography: Fernanda Costa
Abstract
Salicornia gaudichaudiana (Chenopodiaceae) is a halophyte plant that grows in high-level salt soil. Plant material is used as ‘green salt’ in food preparations for people with high blood pressure and kidney / heart diseases. Countercurrent chromatography (CCC) is a form of liquid-liquid partition chromatography in which the stationary liquid phase is retained in the apparatus without the use of a solid support. A large variety of solvent systems (SoSy) have been proposed and employed in CCC which, despite being an efficient technique, will not separate compounds of a complex mixture without the appropriated system. This study describes the influence of SoSy selectivity on the separation of S. gaudichaudiana metabolites. HEMW at 0.5:6:0.5:6 and HBuWat 1:1:2, medium polarity SoSy, gave good distribution of compounds between the two phases. Two CCC runs were performed at identical experimental conditions using the two SoSy. Odd fractions were analyzed by decoupled ESI-MS/MS for metabolite monitoring. Selected ion traces in the two reconstituted CCC-ESI-MS/MS allowed the visualization of the SoSy selectivity for major compounds. In general, HEMW at was more selective and distributed all compounds along the CCC separation with isolation of flavonol glycosides, although co-elution of dicaffeoylquinic acids occurred. HBuWat with less general compound selectivity fractionated isomeric caffeoyl-quinic acids. The SoSy selectivity in CCC is very important when having a target compound in a complex mixture. The strategic use of different SoSy in a specific sequence can influence the results. From the results of our study we could plan to isolate the flavonoids with HEMW at SoSy and then re-fractionate the sample with HBuWat for the isolation of caffeoyl-quinic acid isomers.