Petroleum ether

All solvents used for UHPLC-DAD-ESI-MS, i.e., acetonitrile (99.9%, LC/MS grade) and water (LC/MS grade), were purchased from Thermo Fisher Scientific (Waltham, MA, USA). Petroleum ether (95% GC/MS grade, 40–65 °C) and n-alkanes (C₈–C₂₀) were purchased from Carlo Erba Reagents S.A.S. (Barcelona, Spain) and Fluka, Sigma-Aldrich (Burlington, MA, USA), respectively. Methanol (99.8%, HPLC grade) and water (HPLC grade) used for the extraction were purchased from Thermo Fisher Scientific (Waltham, MA, USA). HPLC reference standards rosmarinic (≥99% analytical standard) and carnosic acid (≥90%) were purchased from Extrasynthese (Genay Cedex, France), while luteolin 7-O-glucoside (≥95%) was from Phytolab (Vestenbergsgreuth, Germany). Bovine Serum Albumin (BSA) Fraction V (lyophilized powder >95%) was purchased from Pan Biotech (Aidenbach, Germany), 2-deoxy-d-ribose (>99%) from Alfa Aesar (Kandel, Germany), aminoguanidine bicarbonate salt (>98%) from Sigma-Aldrich (St. Louis, MO, USA), sodium azide (>99%) and trichloroacetic acid (TCA) (>99.5%, pharma grade) from PanReac AppliChem ITW Reagents (Barcelona, Spain). Anhydrous sodium sulphate (>99%) was purchased from Penta Chemicals (Prague, Czech Republic) while disodium hydrogen phosphate (>99%) and sodium dihydrogen phosphate dihydrate (>99%) were purchased from Merck (Kenilworth, NJ, USA).

Petroleum ether (Carlo Erba, Spain) boiling at 40–70 °C was used for Soxhlet extraction. Chemicals for the determination of polyphenol and antioxidant content were 97% ethanol (Reanal, Hungary), 99% methanol (Reanal, Hungary), anhydrous sodium carbonate (Riedel–de Haen, Germany), Folin–Ciocalteu reagent (Merck, Germany), 2-4-6-tripyridyl-s-triazine (TPTZ) (Sigma-Aldrich, USA), acetic acid (Reanal, Hungary), anhydrous iron chloride (Merck, Germany), 98% Trolox (Sigma-Aldrich, USA), gallic acid (Sigma-Aldrich, USA).