Ezchrome elite

The flavonol composition and trans-resveratrol content of the extracts were assessed by HPLC analysis using the chromatographic system VWR La Prep Σ (Knawer, Germany), which consists of an LP 1100 HPLC pump, LP 3104 UV absorbance detector and column Chromolith^® Performance RP-18e (100 × 4.6 mm × 2 μm), sourced from Merck, Darmstadt, Germany. The managerial chromatography system and data processing used EZChrome Elite, a software of Agilent—version 3.2.0. The column temperature was maintained at 25 °C. Mobile phase A was methanol, mobile phase B was acetonitrile and mobile phase C was water. The water used for the analysis had ultrapure-grade water. The mobile phase solvents underwent filtration through 0.45 μm membrane filters (Millipore, Milford, MA, USA) before analysis. The HPLC analysis was performed using an isocratic program as follows: 0–15 min, 46% A to 12% B to 42% C. The injection volume was 20 μL, the mobile phase flow rate was 0.78 mL/min and the detection wavelength was 360 nm for flavonols and 310 nm for trans-resveratrol. The samples were determined by the retention time of rutin, myricetin, quercetin, kaempferol and trans-resveratrol standards.

TSK G2000 and TSK G3000 SWXL columns (7.8 × 300 mm, column guard, Knauer HPLC device, Pump 1000 smart line, and Autosampler 3950 smart line) were used to quantify the small percentage of conjugates and to separate and change the molecular weight dispersion of each component in the reaction. The mobile phase was 10 mM ammonium carbonate buffer (pH = 7) with a flow rate of 0.5 ml/min (injection volume = 100 µl). A 2500 smart‐line UV Detector was used for detection at a wavelength of 215 nm and a running time of 25 min. The analysis of the results was done by EZ Chrome Elite software (Agilent).