Determination of Free Phenolic Acids in Wort and Beer by Coulometric Array Detection

Phenolic compounds were extracted from rye caryopses with 80% (v/v) methanol. Phenolic acids were determined as free compounds and those liberated from soluble esters and glycosides. The analyses were performed using a Waters HPLC system equipped with a diode array detector (DAD). The following free phenolic acids were found: p-coumaric, ferulic and sinapic; the phenolic acids liberated from soluble esters were as follows: vanillic, caffeic, p-coumaric, ferulic and sinapic; and those liberated from soluble glycosides were the following: vanillic, p-coumaric, ferulic and sinapic. In rye caryopses, phenolic acids were chiefly in the form of soluble esters. A diode array detector was especially useful for the determination of vanillic acid: the UV spectrum of this compound showed a maximum at 260 nm whereas UV spectra of other phenolic acids were characterised by maxima at longer wavelengths.

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Simultaneous determination of phenolic acids and flavonoids in rice using solid-phase extraction and RP-HPLC with photodiode array detection

Journal of Separation Science ◽

10.1002/jssc.201200140 ◽

2012 ◽

Vol 35 (13) ◽

pp. 1603-1611 ◽

Cited By ~ 64

Author(s):

Maria N. Irakli ◽

Victoria F. Samanidou ◽

Costas G. Biliaderis ◽

Ioannis N. Papadoyannis

Keyword(s):

Solid Phase Extraction ◽

Simultaneous Determination ◽

Phenolic Acids ◽

Solid Phase ◽

Phase Extraction ◽

Photodiode Array Detection ◽

Rp Hplc ◽

Photodiode Array ◽

Array Detection

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Determination of free phenolic acids from leaves within different colored maize

Journal of the Serbian Chemical Society ◽

10.2298/jsc160512104m ◽

2017 ◽

Vol 82 (1) ◽

pp. 63-72 ◽

Cited By ~ 1

Author(s):

Jelena Mesarovic ◽

Vesna Dragicevic ◽

Snezana Mladenovic-Drinic ◽

Danijela Ristic ◽

Natalija Kravic

Keyword(s):

Phenolic Acids ◽

High Performance ◽

Limit Of Detection ◽

Principal Component ◽

Dry Weight ◽

Fermented Food ◽

Array Detector ◽

Maize Leaves ◽

Free Phenolic Acids

Along with other plant parts, maize leaves are widely used for making fermented food for cattle, known as silage. Since there have been only a few reports on studies concerning the extraction and determination of phenolic acids from maize leaves, the main goal of this experiment was to evaluate free phenolic acids content in leaves of fifteen different maize inbred lines. Reverse-phase high performance liquid chromatography (RP-HPLC), equipped with photodiode array detector (DAD), was performed. Under the optimization of chromatographic conditions, referring to short time of samples preparation, small quantities of solvent and direct injection of extract into HPLC, phenolic acids (i.e. gallic, protocatechuic, caffeic, p-coumaric and ferulic acid) were successfully separated in less than 25 min, indicating that the method can be applied for routine analysis. The efficiency and validation of the method was evaluated by measuring the rate of parameters: linearity, limit of detection and quantification, accuracy and precision. Results obtained revealed that the most abundant free phenolic acid was p-coumaric acid (23.57 ?g g-1 dry weight), followed by ferulic and caffeic acids (21.27 and 20.78 ?g g-1 dry weight, respectively). Principal Component Analysis (PCA) revealed the existence of link.

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