High-performance counter-current chromatography as a tool for the enrichment and identification of phenolic compounds

FONTANA, ARIEL RAMÓN; SCHIEBER, ANDREAS

Río de Janeiro

Conferencia; 12th Countercurrent Chromatography Conference; 2024

Universidad Federal do Rio de Janeiro

The application of high-performance counter-current chromatography (HPCCC) as a tool for the isolation and fractionation of phenolic compounds (PCs) prior to their analytical profiling in extracts from wine industry by products (wine lees (WL) and grape pomace (GP)) is presented. After refining the ethanol:water extracts of GP and WL by-products by ethyl acetate extraction and performing an HPCCC separation with the n-hexane:ethyl acetate:methanol:water (1:5:1:5) biphasic system, an enriched fraction of the minor family of flavonols was obtained. Starting from 500 mg of ethyl acetate extract (equivalent to 10 g of by-product), recoveries of 112.9 and 105.9 mg of purified flavonols (myricetin, quercetin, isorhamnetin, and kaempferol) in GP and WL, respectively, were attained. The usefulness of HPCCC for the fractionation and concentration of analytes was also explored for the profiling and tentative identification of constitutive PCs by ultra-high performance liquid chromatography-mass spectrometry. A total of 57 PCs in both matrices was identified, 12 of which were not previously reported. The results indicate that the application of HPCCC to GP and WL extracts may be a powerful approach to isolate large amounts of minor PCs to perform correlation studies between structure, synergy, and bioactivity in different systems. The composition of the enriched flavonol fraction for each matrix demonstrated quantitative differences in the individual compounds, supporting the potential exploitation of these matrices as sources of specific flavonols for technological applications.