Various honey samples, as well as their constituents, were
subjected to determination of HPS activity using a recently
developed DC polarographic assay for the first time. Due to its
complexity in terms of the presence of various AOs and the huge
amount of reducing sugars, honey represents a challenging
sample for direct determination of AO activity. Honey HPS
activity reflects the combined action of the complex mixture of
various substances. Although contribution of phenolics is
predominant, honey HPS activity depends also on nonphenolics.
Since honey is a supersaturated solution of sugars,
the fact that activities of individual sugars were found to be
measurable gains importance. Glucose and fructose have very
low HPS activity but their contribution to total activity is
significant due to their quantity, as HPS activity of artificial
honey confirms. In addition, other non-phenolic compounds
also possess HPS activity, some of them in the range of
phenolics. Although phenolics are minor honey constituents
their HPS activity is high enough to enable direct measurement
as proved by high correlations between honey HPS and total
phenolic content. Thereafter, distinction of honeys of different
floral sources based on HPS activity was found to be possible.
Results of polarographic measurements were compared for the
fist time with assays other than FC and DPPH, FRAP, TEAC and
ORAC. Strict correlations between HPS and AO activity
measured by five standard spectrophotometric assays allowed
speculations on HPS assay validity. This validity was confirmed