In vitro antioxidant activity of honeydew and multifloral types of honey from Serbia

Abstract

Antioxidant properties of fifteen multifloral and honeydew types of honey from Serbia were assessed by determination of ferric-reducing antioxidant power (FRAP assay) and 2,2- diphenyl-1-picrylhydrazyl free radical scavenging ability (DPPH assay), with respect to their total polyphenol content and colour intensity. The results of this study showed that total polyphenol content, antioxidant activity and colour intensity varied widely among different samples, even within the same type of honey. All investigated parameters were strongly dependent on geographic origin of samples, further emphasizing the importance of their detailed chemical characterisation. In general, polyphenolic content in investigated samples of honey, expressed as catechin equivalents, ranged from 480.2 to 1861.1 mg/kg. The ferric-reducing antioxidant power of honey tended to be lower in brighter and higher in darker samples, varying between 489.6 and 3089.8 μmol Fe(II) per 100 g of honey. The correlation between the colour and antioxidant activity never reached statistical significance in the case of honeydew type of honey, which was opposed to a trend observed in the case of multifloral honey.

U ovom radu, ispitivana su antioksidantna svojstva petnaest uzoraka livadskog i šumskog meda, primenom Ferric-Reducing/Antioxidant Power i DPPH-free radical scavenging ability testa, u odnosu na sadržaj ukupnih polifenolnih sastojaka i intenzitet boje meda. Rezultati ovog ispitivanja su pokazali da su sadržaj ukupnih polifenola, antioksidantna aktivnost i intenzitet boje izrazito varirali od jednog uzorka do drugog, čak i u okviru svake vrste meda ponaosob. Svi ispitivani parametri su bili vrlo zavisni od geografskog porekla uzoraka, naglašavajući važnost detaljne hemijske karakterizacije meda. Generalno, sadržaj ukupnih polifenola u ispitivanim uzorcima meda, izražen u ekvivalentima katehina, kretao se u intervalu od 480,2 mg/kg do 1861,1 mg/kg. Sposobnost redukcije gvožđa bila je niža u svetlijim vrstama meda, a viša u tamnijim, varirajući između 489,6 i 3089,8 μmol Fe(II) na 100 g meda. Korelacija između intenziteta boje i antioksidantne aktivnosti nije imala statističku značajnost kod uzoraka šumskog meda, nasuprot trendu koji je uočen u slučaju livadskog meda.