Effect of honey on purified equine myeloperoxidase activity and superoxide radical production in activated Polymorphonuclear neutrophils

Abstract

Three Algerian honey samples (nectar honey, mixed honey and honeydew honey) were analysed for their total phenolic content (TPC) using the Folin-Ciocalteu reagent and total flavonoid content (TFC) by the aluminium chloride method. The antioxidant activity was tested both against reactive oxygen species (ROS) produced by phorbol 12-myristate 13-acetate (PMA)-stimulated equine polymorphonuclear neutrophils (PMNs) and on purified equine myeloperoxidase (MPO) enzyme activity. The ROS production by stimulated PMNs was measured by lucigenin-enhanced chemiluminescence. Specific immunological extraction followed by enzymatic detection (SIEFED) was used to measure specifically the activity of equine MPO. Nectar honey, mixed honey and honeydew honey had TPCs of 59.52 ± 1.31, 68.36 ± 1.20 and 122.76 ± 4.20 mg gallic acid equivalents (GAE)/100 g honey, respectively (mean ± SD). As for the TPC, the highest TFC was observed for honeydew honey [20.55 ± 0.72 mg catechine equivalents (CE)/100 mg honey], followed by mixed honey (7.47 ± 0.07 CE/100 mg honey) and nectar honey (4.80 ± 0.08 CE/100 mg honey). All the tested honeys displayed a dosedependent inhibitory effect on the oxidant activities of PMNs. By the SIEFED technique, it was shown that most of the honeys interact directly with MPO: the light honeys (nectar honey and mixed honey) were inhibitors of MPO activity, while the dark honey had less inhibiting effect and even behaved as an enhancer of MPO activity at high concentrations.

Effect of honey on oxidation, chlorination and nitration by purified equine myeloperoxidase

“…According to Moniruzzaman et al[28], the use of DPPH assay coupled with various other useful methods such as FRAP are preferred because they are able to reflect the antioxidant properties of honey more accurately. In a previous studies of us [29], using the same samples, we have shown that HH had the highest contents of phenolics and flavonoids and the darkest color, meanwhile NH had the lowest contents of phenolics and flavonoids and the lightest color. In the present study, HH exhibited the highest DPPH radical-scavenging activity and fraps value and NH the lowest.…”