Phenolic Composition and Antioxidant Properties of<i>Rhododendron ponticum</i>: Traditional Nectar Source for Mad Honey

Abstract

AbstractRelying on nectar of the Rhododendron plant species, honeybees produce mad honey which is marketed relatively at high cost due to its enormous medical uses. Herein, Rhododendron ponticum was chemically characterized regarding total phenolics, antioxidant properties and profile of phenolic compounds to present authentic data of the major source of Mad honey. To distinguish, flowers of the plant were divided into two parts, corolla and calyx. Antioxidant activity of the extracts was examined by two different methods; scavenging of free radical of ABTS and DPPH. For the first time 9 phenolic acids and 3 flavonoids are found from this species on high performance liquid chromatography (HPLC). In comparaison with leaves, methanolic extract of flowers showed the highest total phenolic contents as Gallic Acid Equivalent (349.53±0.346 mg/100 g), total flavonoid contents as Quercetin Equivalent (311.16±1.669 mg/100 g) as well as antioxidant activity with IC50 of 1.23, 1.30 mg/mL in DPPH and ABTS assays.Key words: Antioxidant activityHPLCmad honeyphenolic compoundsRhododendron ponticum