Isorhamnetin 3 rutinoside

4-Hydroxybenzaldehyde, 4-hydroxybenzoic acid, caffeic acid, homovanillic acid, vanillic acid, protocatechuic acid, phloroglucinol aldehyde, hippuric acid, ferulic acid, p-coumaric acid, quercetin, chlorogenic acid, neochlorogenic acid, epicatechin, catechin, kaempferol, kaempferol-3-rutinoside, 3-hydroxyphenylacetic acid, 3,4-dihydroxyphenylacetic acid, isorhamnetin-3-rutinoside, naringenin, isorhamnetin, rutin, quercetin, quercetin-3-rhamnoside, quercetin-3-glucoside, 4-methylcatechol, benzoic acid, DMSO-d₆, CD₃OD, Griess reagent A, Griess reagent B, cell proliferation kit I (MTT), and bovine serum albumin (BSA) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Proanthocyanidins B2, B5, and C1 were obtained from Plantchem (Klepp, Norway). Dulbecco‘s modified Eagle’s medium (DMEM-Glutamax™, 5.5 mM), fetal bovine serum, and penicillin–streptomycin–amphotericin B were obtained from Gibco Life Technologies (Paisley, UK). Corning CellBIND tissue culture plates were obtained from Corning Life-Sciences (Schiphol-Rijk, The Netherlands). All other reagents were of the highest purity available.

The deionized water used for the sample extraction was purchased from Millipore (Bedford, MA, USA), whereas the methanol, formic acid (FA), and water (LC–MS grade) used for the chromatography were provided by Carlo Erba reagents (Milan, Italy). The polyphenol standards (purity > 98%), namely protocatechuic acid, gallic acid, quinic acid, apigenin-7-O-glucoside, p-coumaric acid, catechin, epicatechin, chlorogenic acid, rosamarinic acid, hesperidin, quercetin-3-galattoside, rutin, naringin, ferulic acid, apigenin, luteolin, gallic acid, naringenin, quercetin, daidzein, myricetin, isorhamnetin-3-rutinoside, genistein, diosmin, and ellagic acid kaempferol-3-glucoside were purchased from Sigma-Aldrich (Milan, Italy). In order to perform antioxidant tests, hydrochloric acid, 1,1-diphenyl-2-picrylhydrazyl (DPPH), potassium persulphate, 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) were provided by Sigma-Aldrich (Milan, Italy). The enzymes and standards used in the simulated GI, namely pancreatin, α-amylase (1000–3000 U/mg solid) from human saliva, bile salt, pepsin (≥2500 U/mg solid) from porcine gastric mucosa, Pronase, and Viscozyme L., were purchased from Sigma-Aldrich (Milan, Italy).