Rapid Determination of Simple Polyphenols in Grapes by LC Using a Monolithic Column

Abstract

The development of a rapid, reliable and reproducible LC method for the determination and quantification of 13 polyphenols (gallic acid, protocatechuic aldehyde, gentisic acid, catechin, vanillinic acid, caffeic acid, vanillin, epicatechin, syringaldehyde, p-coumaric acid, ferulic acid, sinapic acid and resveratrol) in grapes and derived products is reported. The polyphenols were separated in less than 8 min. Employed was an RP-18e (100 mm 9 4.6 mm) monolithic type column. A gradient method with the following solvents was utilised for the chromatographic separation: A: 90% water, 2% acetic acid in methanol, and B: 90% methanol, 2% acetic acid in water. Two detectors in series were employed: a UV-Vis detector and a fluorescence excitation/emission detector. Influence of temperature (15-40°C) and solvent flow rate (2-5 mL min-1) on the separation were studied, and 25°C and 2.5 mL min-1 were found to be the optimum conditions. The relative standard deviations of the resulting peak areas, for both intra-and inter-experiments, were less than 2.4 and 2.6%, respectively. Finally, the developed method has been utilised for the quantification of the polyphenols in real samples.

Analysis of Phenolic Compounds in Lager Beers of Different Origin: A Contribution to Potential Determination of the Authenticity of Czech Beer

“…Because of the unsatisfactory results obtained, four slightly modified isocratic mobile phases were tested. Similarly to recent findings, we found that the presence of methanol negatively affected resolution and increased analysis time [11][12][13][14]. Thus, methanol was excluded from the mobile phase and gradients were tested using acetonitrile and acidified water.…”

“…In accordance with recent findings, acetonitrile and deionized water were used as the main components of the mobile phase [3][4][5][6][7][11][12][13][14]. Successful separation requires addition of acidic additives [11].…”

“…Many modern techniques have been used to characterize and identify phenolic compounds in food [4][5][6][7][11][12][13]. Beer samples can be analyzed without pre-treatment or after purification and pre-concentration [11].…”

Effect of Torulaspora delbrueckii Yeast Treatment on Flavanols and Phenolic Acids of Chenin blanc Wines

“…spectroscopic (Andersen & Markham, 2007) or chromatographic techniques (Stefova et al, 2003;CastilloMuňoz et al, 2010;Moreno et al, 2015;Nelson et al, 2016). Reversed-phase high performance liquid chromatography (RP-HPLC) coupled to a photodiode array detector (DAD) is one of the more commonly used methods for the separation and quantification of phenolic compounds in wine (De Villiers et al, 2004;Liazid et al, 2010;Lorrain et al, 2011;Fanali et al, 2013;Favre et al, 2014;Garaguso & Nardini, 2015;Nelson et al, 2016). The use of RP-HPLC-DAD constitutes a reliable tool for the quantification of phenolic compounds by allowing maximum absorbance, controlling peak purity and identifying compounds by means of UVvisible spectra and relative retention times.…”

Rapid Determination of Trifluoromethanesulfonate and p-Toluenesulfonate by Ion-Pair Chromatography Using a Reversed-Phase Silica-Based Monolithic Column: Application to the Analysis of Ionic Liquids

“…These allow higher flow-rates of eluent due to lower back-pressures without much loss of performance [20,21]. In the recent years, the preparation and application of monolithic columns have been developed rapidly in HPLC and IC [21][22][23][24][25][26]. The main forms of monoliths are organic polymer monoliths and silica-based monoliths.…”