Physicochemical properties, chemical constituents, and antioxidant activity of Eurya honey

Eurya honey (EH) is produced from the nectar of Eurya. In this paper, the physicochemical properties (moisture, free acidity, pH, 5-hydroxymethylfurfural, conductivity, sugar, and colour) of EH were systematically studied for the first time. The total phenols and flavonoids were determined by spectrophotometry, and the contents were 40.29 +/- 4.17 mg GAE/100 g and 12.44 +/- 0.62 mg RE/100 g, respectively. A total of 232 compounds were identified, and 30 of them were quantified by ultra-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UPLC-Q/TOF-MS). The potential markers of EH were abscisic acid (21.3-103.4 mu g/100 g), gallic acid (6.9-220.2 mu g/100 g), tricoumaroyl spermidine (284.2-518.1 mu g/100 g), and kaempferol (15.0-258.7 mu g/100 g). EH showed antioxidant capacities in DPPH free radical-scavenging activity (IC50: 42.87-131.26 mg mL(-1)), ferric reducing antioxidant capacity (23.22-112.24 mu mol FeSO4 center dot 7H(2)O/100 g), and ABTS radical-scavenging activity assays (9.51-31.21 mu mol Trolox/100 g).