Honey contains important bioactive compounds (enzymes, phenolic compounds, vitamins, and minerals) with several positive health effects for humans. In the study six types of honey (acacia, rape, floral, multi flower, forest, and honeydew honeys), of Czech and Slovak origin, were evaluated for bioactive compounds by means of color, polyphenols and antioxidant capacity analyses. The brightest color of honeys, the lowest values measured spectometrically, had acacia and rape honeys, followed by floral, and darker multi flower and forest honeys, and honeydew honeys. Polyphenols (PP) amount, determined by spectrophotometric method with Folin-Ciocalteu reagent, was highest for the darkest honeydew honeys, followed by multi flower and forest honey, brighter floral honeys, and rape and acacia honey. Honeys polyphenols were in the range from 54.0 to 254.2 mg GAE.100g-1. The total antioxidant capacity (TAC) was analyzed by spectrometric methods with ABTS and DPPH reagents. Antioxidant capacity values are in agreement with the PP contents order. They were highest also for honeydew honeys (59.2 - 89.6 and 73.1 - 118.7 mg TE.100g-1), followed by multi flower (66.0 and 56.7 mg TE.100g-1) and forest honey (56.0 and 49.1 mg TE.100g-1), then floral honeys (33.0 - 49.2 and 27.8 - 38.7 mg TE.100g-1) and the lowest values for rape (19.0 and 28.1 mg TE.100g-1) and acacia (15.5 and 11.3 mg TE.100g-1) honey. A positive correlation between color, PP amount and TAC was evaluated for analyzed honeys. Darker honey samples showed higher values of phenolic compounds and antioxidant potential, therefore they belong to the honey types with higher amount of bioactive compounds such as antioxidants.
Comparative Evaluation of Various Total Antioxidant Capacity Assays Applied to Phenolic Compounds with the CUPRAC Assay