D xylose

The water used was Milli-Q water (Millipore Corporation, Molsheim, France) with a conductivity of 18 MΩ cm^–1. High-performance liquid chromatography (HPLC)-grade methanol and formic acid were used as the solvents for the HPLC analysis and were obtained from Sigma-Aldrich. Ethanol (99.5%) was obtained from VWR (Fontenay-sous-Bois, France). The phenolic standards, cyanidin chloride, malvidin chloride, delphinidin chloride, p-coumaric acid, ellagic acid, resveratrol, gallic acid, caffeic acid, polydatin, epicatechin gallate, epicatechin, vanillin, and vanillic acid, were purchased from Extrasynthese (Genay, France). Bovine serum albumin (BSA) was purchased from Sigma-Aldrich (St. Louis, MO, U.S.A.). Tartaric acid, NaN₃, and NaNO₃, p.a. grade, were from Merck (Darmstadt, Germany). Folin–Ciocalteu reagent was purchased from Sigma-Aldrich (St. Louis, MO, U.S.A.), and sodium carbonate was purchased from Merck (Darmstadt, Germany). HCl was purchased from VWR International (Rue Carnot, France). The sugars used as standards were l(+)-rhamnose monohydrate, d(+)-galactose, and d(+)-glucose from Merck, l(+)-arabinose from VWR Chemicals, d(+)-xylose from PanReac AppliChem (Darmstadt, Germany), and d(+)-mannose from Sigma-Aldrich.