Hlp 5 deionizer

Analytical-grade reagents such as aluminum chloride, sodium nitrite, metaphosphoric acid, Carrez solutions, KH₂PO₄ (ABChem, Olsztyn, Poland), 2,2’-Azobis(2-amidinopropane) dihydrochloride (AAPH), 2,2-diphenyl-1-picrylhydrazil (DPPH), gallic acid, apigenin, fluorescein, Folin-Ciocalteau reagent and Trolox, ethanol, hydroxy methyl furfural (HMF), ascorbic acid, fructose, glucose and saccharin (Sigma-Aldrich, Saint Louis, MO, USA), sodium carbonate and sodium hydroxide (POCH, Gliwice, Poland) were used. Other applied reagents, i.e., methanol, acetonitrile was of the highest purity (chromatography-grade) available and purchased from the Sigma-Aldrich Chemical Company (Saint Louis, MO, USA). Deionized water was obtained from HLP 5 deionizer (Hydrolab, Gdańsk, Poland).

Analytical-grade reagents and solvents, i.e., Folin–Ciocalteu reagent from Sigma-Aldrich (Saint Louis, MO, USA), anhydrous sodium sulfate (Na₂SO₄), chloroform, diethyl ether, ethanol (99.9% purity), formic acid, methanol, potassium hydroxide (KOH), sodium carbonate (Na₂CO₃), sulfuric acid (H₂SO₄), and zinc purchased from Chempur (Piekary Śląskie, Poland) were used. Chromatography-grade solvents, i.e., dichloromethane, ethanol, methanol, n-hexane, heptane, methyl tert-butyl ether, iso-propanol, pyridine, and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS) were purchased from Sigma-Aldrich (Saint Louis, MO, USA). Analytical standards such as 5α-cholestane, margaric acid, β-apo-8’-carotenal, D-catechin, phenolic acids (p-coumaric acid (p-CA), dihydroferulic acid (DHFA), sinapic acid (SA), vanillic acid (VA)), and 4-vinylguaiacol (4-VG) were purchased from Sigma-Aldrich (Saint Louis, MO, USA), while tocopherols (α-, γ-, and δ-tocopherol) were purchased from Calbiochem (Nottingham, UK). Deionized water was obtained from HLP 5 deionizer (Hydrolab, Gdańsk, Poland).