2.8. Analysis of individual phenolic acids
Chromatographic analyses were performed on a ThermoScientific Ultimate 3000 HPLC system consisting of photodiode
array detector, quaternary pump, autosampler and column oven.
Phenolic acids were separated on a Thermo Scientific Hypersil
GOLD aQ C18 column (150 mm 4.6 mm, i.d., 3 mm) using a linear
gradient elution program with a mobile phase containing solvent A
(formic acid/H2O, 1:99, mL:mL), and solvent B (methanol) at a flow
rate of 0.8 mL/min. The solvent gradient was programmed as
described by Zili c et al. (2012). The chromatograms were recorded
at 280 nm by monitoring spectra within the wavelength range
190e400 nm. Identified phenolic acids peaks were confirmed and
quantified by data acquisition and spectral evaluation using the
Thermo Scientific Dionex Chromeleon 7.2. chromatographic
software.