Comparative study of the cheical composition and biological potential of honey from different regions of Serbia

Abstract

A chemical characterization and biological activity of 7 honey types (multifloral, linden, rapeseed, sunflower,phacelia, acacia and honeydew honey) from different regions of Serbia were presented. The physicochemicalcharacteristics, mineral content, antioxidant and antimicrobial activity were estimated and discussed. All honeysshowed good nutritional characteristics, according to the adopted criteria of the standard codex for honey. Theconcentrations of 15 elements in honey samples were determined using inductively coupled plasma opticalemission spectroscopy (ICP-OES). Limits of quantification were in the range from 0.003 mg/kg (Cd, Cr, Cu, Mn,and Pb) to 1.50 mg/kg for sodium. Precision was expressed as relative standard deviation and its values werelower than 1.50%. Accuracy was evaluated with certified reference material (fish protein, DORM 4, NRC andcooking chocolate, SRM 2384, NIST) and obtained recovery percentages were 71-127%. The content of the mostabundant elements (K, Mg, and Na) and microelements (Al, Cu, Fe, Mn, Ni, Se, Si, and Zn) showed a significantvariability in accordance of their botanical and geographical origin, but also the influence of harvest conditions.The levels of toxic metals (As, Cd, Cr, and Pb) are much lower than the maximal allowed for these metalsaccording to European Commission Regulation. The antioxidant activity was evaluated by DPPH(Diphenylpicrylhydrazyl) assay while antimicrobial activity against Gram positive and Gram negative bacteria(E. coli and S. aureus) and fungi Candidi albicans was estimated by microdilution assay. The free radicalscavenging assay (%RSA) varies significantly among the honey samples. The highest antioxidant activity wasobserved with honeydew honeys (over 75% RSA) and the lowest was observed in the acacia, ranging from 22.96to 24.57% RSA. All honeys tested in this study exhibited antibacterial activity, with inhibition of bacterialgrowth, generally the higher against E. coli (80% for linden honeys) than against S. aureus (mostly much lowerthan 50%). Activity against Candidi albicans was almost negligible. The dataset composed of all experimentalresults was subjected to a chemometric evaluation and cluster analysis as hierarchical nonsupervised methodwas applied. According to the obtained outcome of applied algorithms, both botanical and geographical originhave important role in the elemental composition, antioxidant and antimicrobial activities.