Antioxidant and anti-glycation activity of eight Moroccan honeys from different botanical origins

Abstract

Eight monofloral honey samples from different botanical and geographical origins in the central and eastern parts of Morocco were examined for their phenolic composition, capacity to scavenge free radicals, and ability to inhibit advanced glycation end–products. According to the melissopalynological analysis, the examined honey samples were considered to be natural honeys, and were classified as monofloral with very frequent pollen grains characteristic of each types of the selected Moroccan honey samples: Zantaz (Bupleurum sp.), fennel, thistle, eucalyptus, spurge, thyme, jujube, and carob. Our results showed that the average moisture content varied from 16.3 ± 0.1% to 19.9 ± 0.1%, and the mean color intensity ranged from 30.94 ± 7.42 to 166.9 ± 6.43 mm Pfund. The highest total phenolic content recorded was 163.83 ± 1.84 mg of gallic acid equivalent per kg, while the highest flavonoid content was 84.44 ± 1.20 mg of catechin equivalent per kg. Zantaz honey exhibited potent antioxidant capacity, as demonstrated by ABTS, DPPH, β-carotene bleaching, FRAP, and ORAC assays. The most significant results were obtained for the ORAC test, with the highest ORAC value of 4.65 mM Trolox equivalent per gram was recorded for Zantaz honey extract. HPLC–DAD analysis revealed different polyphenolic profiles, which can be attributed to differences in floral origin. Furthermore, our study revealed that the extracts of thistle honey, fennel honey, and Zantaz honey were the most effective glycation inhibitors, with the highest inhibition percentage of 96% obtained for the thistle honey extract.