2 2 azinobis 3

The 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,4,6-tripyridyl-s-triazine (TPTZ), potassium persulfate, hydrochloric acid, ferric chloride, iron(II) sulfate heptahydrate, sodium phosphate, sodium hydroxide and ammonium persulfate were purchased from Sigma-Aldrich (Milan, Italy). The phenolic compounds, gallic acid and quercetin, were purchased from Sigma Chemical Co. (St Louis, MO, USA). Analytical grade reagents, such as sodium carbonate, potassium hydroxide, Folin-Ciocalteu reagent, ethanol, methanol and hexane were obtained from Panreac (Barcelona, Spain). Aluminum chloride, potassium ferricyanide, ferric chloride and trichloroacetic acid were from Sigma Chemical Co. (St. Louis, MO, USA). The water was treated in a Milli-Q water purification system (TGI Pure Water Systems, Brea, CA, USA). Coomassie Brilliant blue G250 was purchased from Bio-Rad (Richmond, CA, USA). The spectrophotometer UV-VIS Spectrophotometer 1204 (Shimadzu, Japan) was used. MINOLTA Chromameter CR-300 (Minolta Camera Corp., Meter Division, Ramsey, NJ, USA) equipped with a D65 illuminant, 10° Observer and zero and white calibration was used to measure the color parameters (CIE L*, a*, b*).

Benitaka grape (Vitis vinifera L. fruits) was purchased in single batch in a local supermarket. Dimorphandra mollis Beth fava beans were harvested in Private Biological Reserve (22°18′S/47°11′W), in Mogi Guaçu (São Paulo, Brazil), in May 2015. Ruta graveolens leaves were harvested in the Chemical, Biological and Agricultural Pluridisciplinary Research Center—CPQBA (22°48′S/47°0′W) at the University of Campinas (UNICAMP) (Campinas, São Paulo, Brazil) in April 2015. Ginkgo biloba L. dry extract was purchased at Galena (Campinas, São Paulo, Brazil). Ethyl alcohol, acetic acid, hydrochloric acid, boric acid, oxalic acid, acetone, ether, metallic magnesium, metallic zinc, ferric chloride, and aluminum chloride were provided by Synth (São Paulo, Brazil), and 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2-2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH), and fluorescein by Sigma-Aldrich (São Paulo, Brazil). Quercetin (93.3% purity) and rutin (97.3% purity) standard by Acros (Sao Paulo, Brazil). RPMI-1640 and fetal bovine serum were provided by Gibco (Sao Paulo, Brazil) and Tris [hydroxymethyl] aminomethane and neutral red dye was provided by Sigma-Aldrich (São Paulo, Brazil).

2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 1-aminobeznotriazole (ABT) were obtained from Sigma-Aldrich (Germany). Stock solutions of ABT were prepared in ethanol at a concentration of 50 mM.
o-tolidine was purchased from Chempur (Poland). A stock solution of o-tolidine (10 mg mL^-1) was prepared in ethanol. Liquid chromatography solvents were obtained from Avantor Performance Materials (Poland).
The azo dyes Reactive Orange 16 (CAS 12225–83-1), Acid Red 27 (CAS 915–67-3), Acid Orange 7 (CAS 633–96-5), Reactive Red 120 (CAS 61951–82-4), and Reactive Black 5 (CAS 17095–24-8) were purchased from Sigma-Aldrich (Germany). Stock solutions were prepared in water at a concentration of 50 mg mL^-1.
Cd(NO₃)₂ × 4 H₂O, K₂Cr₂O₇, and ZnSO₄ × 7 H₂O were purchased from Sigma-Aldrich (Germany). Metal stock solutions were prepared by dissolving in deionized water at a concentration of 1 M.
Samples of landfill leachate (L1 and L2) collected from the landfill of the former “Boruta” Dye Industry Plant in Zgierz, Poland (Fig. 1) were kindly supported by the Voivodeship Inspectorate of Environmental Protection in Łódź, Poland.

All reagents and solvents used in this study were of analytical grade. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals and carrageenan were purchased from Sigma-Aldrich (St. Louis, MO, USA).

The 2,2′-azinobis(3-ethylbenothiazoline-6-sulphonic acid) diammonium salt (ABTS), 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ), Folin-Ciocalteu’s phenol reagent, and the standard compounds (gallic acid, protocatechuic acid, gallo catechin, chlorogenic acid, cyanidin-3-glucoside, caffeic acid, epicatechin, catechin gallate, p-coumaric acid, ferulaic acid, melatonin, 2-hydroxycinnamic acid, rutin, resveratrol, daidzein, equol, quercetin and genistein) were provided by Sigma-Aldrich (St. Louis, MO, USA). Tetrahydrofuran, methanol, formic acid, diethyl ether and ethyl acetate were provided by Kermel Chemical Factory (Tianjin, China). Acetic acid, sodium acetate, potassium acetate, sodium hydroxide, hydrochloric acid, ethylenediaminetetraacetic acid (EDTA), ascorbic acid, iron (III) chloride hexahydrate (FeCl₃·6H₂O), iron(II) sulphate heptahydrate (FeSO₄·7H₂O), potassium persulphate, sodium carbonate, aluminum chloride hexahydrate (AlCl₃·6H₂O), ethanol and n-hexane were provided by Damao Chemical Factory (Tianjin, China). All chemical reagents used in the tests were of analytical or chromatographic grade, and the water used was double distilled.

2,2′-Azobis(2-amidonopropane) hydrochloride (AAPH), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox); Folin-Ciocalteu’s phenol reagent; 2,4,6-tris(2-pirydylo)-1,3,5-triazyn (TPTZ); iron (III) chloride hexahydrate; sodium acetate; acetic and hydrochloric acid, gallic acid and quercetin were purchased from Sigma (Sigma Chemical Co., St. Louis, MO, USA). PCL kits for lipophilic (ACL) and hydrophilic antioxidants (ACW) were bought from Analytik Jena (Leipzig, Germany). Reagents of HPLC-MS grade, including acetonitrile, methanol, water, and formic acid, were purchased from Sigma Chemical Co. (St. Louis, MO, USA).

2,2′-Azinobis 3-ethylbenzothiazoline-6-sulphonate (ABTS), 2,2-diphenyl-1-picrylhydrazyl-hydrate (DPPH), 2,4,6-tripyridyl-s-triazine (TPTZ), 6-hydroxy-2,5,7,8-tetramethyl chroman-2-carboxylic acid (Trolox), ammonium thiocyanate (NH₄SCN), ferrous chloride (FeCl₂), kojic acid, L-tyrosine, linoleic acid, oleanolic acid, ferrous sulfate (FeSO4), potassium persulfate (K₂S₂O₈), sodium acetate trihydrate (CH₃COONa.3H₂O), sodium chloride (NaCl), sodium sulfate anhydrous (Na₂SO₄), and tyrosinase from mushroom (EC 1.14.18.1) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Acetic acid, hydrochloric acid, ethanol, calcium chloride (CaCl₂), chloroform, de-ionized (DI) water, dimethyl sulfoxide (DMSO), glacial Acetic acid, petroleum ether, and sulfuric acid (H₂SO₄) were purchased from RCI Labscan Co., Ltd. (Bangkok, Thailand).