Furthermore, the antioxidant activity of a functional extract rich in anthocyanins was evaluated

in different conditions of pH, through the scavenging capacity of both 2,2′-azinobis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS +) and peroxyl radicals, along with the protective effect against singlet oxygen (1O2). Jambolão mature fruits, harvested in 2008, were directly obtained from producers in the region of Pelotas, Rio Grande do Sul, Brazil. The fruits were stored at −36 °C, and only the edible portion (pulp and peel) was homogenised before the extraction. Standards of cyanidin 3-glucoside, cyanidin 3-galactoside, cyanidin 3-rutinoside, cyanidin 3,5-diglucoside, cyanidin 3-rhamnoside, malvidin 3-glucoside, malvidin 3,5-diglucoside, pelargonidin 3-glucoside, GDC-0941 clinical trial cyanidin, pelargonidin, quercetin 3-galactoside, quercetin 3-rhamnoside, epicatechin, Selleck PCI32765 and gallic, p-hydroxybenzoic, caffeic, coumaric, ferulic and ellagic acids were obtained from Extrasynthèse (Genay, France). Standards of rutin, quercetin 3-glucoside, quercetin, naringenin, luteolin, tannic and ascorbic acids were purchased from Sigma–Aldrich (Munich, Germany). Standards of naringin, myricetin,

apigenin, kaempferol and catechin were obtained from Fluka (Steinheim, Germany). Standards of all-trans-lutein, all-trans-zeaxanthin, all-trans-β-cryptoxanthin, all-trans-β-carotene and all-trans-α-carotene, as well as the isomers 9-cis-, 13-cis- and 15-cis-β-carotene were provided by DSM Nutritional Products (Basel, Switzerland). All standards showed at least 95% purity, determined by HPLC-DAD. The reagents 2,2′-azinobis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), potassium persulphate,

6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), methylene blue (MB), dimethylanthracene (DMA), α,α′-azodiisobutyramidine dihydrochloride (AAPH, PM = 271.19 g/mol), fluorescein as sodium salt (MW = 376.27 g/mol) Urocanase and bovine serum albumin (BSA) were purchased from Sigma–Aldrich and the Folin–Ciocalteau reagent was supplied by Merck (Darmstadt, Germany). Solvents, acids and salts used were pro analysis grade purchased from Labsynth (Diadema, Brazil). Solvents for HPLC were obtained from Merck or Mallinckrodt Baker (Philipsburg, USA). The water was purified by the Milli-Q system (Millipore, Billerica, USA). For chromatographic analysis, samples and solvents were filtered using, respectively, membranes of 0.22 and 0.45 μm, both from Millipore. The quantitative analysis of total phenolics, flavonoids, monomeric anthocyanins, and tannins, as well as some antioxidant tests were performed on a spectrophotometer Agilent 8453 (Santa Clara, USA). The CIELAB colour parameters (L  ∗, a  ∗, b  ∗) of the functional extract, diluted at 0.35%v/v in different buffer solutions (pH 1.0, 3.0, 5.0 and 7.