TAC (ferric reducing antioxidant power, FRAP) was measured in ice-cold 80% ethanol with a MagNALyser (Roche, Vilvoorde, Belgium) and quantified using Trolox as a reference, as reported by Benzie and Strain (1999) (link). Plant samples were extracted in 80% ethanol and measured for ascorbate and glutathione using a MagNALyser (Roche, Vilvoorde, Belgium). Reduced ascorbate (ASC) and glutathione (GSH) were measured using HPLC. To extract phenols and flavonoids, fresh plant materials were homogenized in 80% ethanol before being centrifuged at 5000 rpm for 15 minutes. The clear extract was then used to measure the phenols and flavonoid concentrations using the Folin-Ciocalteu and aluminum chloride assays, respectively (AbdElgawad et al., 2023 (link)). Tocopherols were extracted with hexane (100 mg FW in 6 ml hexane) and centrifuged for 15 minutes at 14,000 g. The extracts were dried (Labconco, Kansas, USA) and resuspended in hexane. HPLC (Shimadzu, Hertogenbosch, the Netherlands) was used to separate and quantify tocopherols under normal phase conditions. Particil Pac 5 mm column material, length 250 mm, i.d. 4.6 mm, and internal standard dimethyl tocol (DMT) (5 ppm). The Shimadzu Class VP 6.14 software was used to examine the data.
Free full text: Click here
