The aim of this thesis was to determine total phenolic and flavonoid content, content of flavonoid subgroups, and antioxidative potential (AOP) of bee pollen. We investigated the influence of storage, heat treatment, and drying method of bee pollen, and the influence of storing bee pollen ethanolic extracts on mentioned parameters. The total phenolic content was determined spectrophotometrically using Folin-Ciocalteu reagent; between 5.7 and 12.4 mg gallic acid/g dry matter was determined in fresh bee pollen, collected in year 2019. AOP was determined by the DPPH• and O2•- radical scavenging method and it was found that the investigated bee pollen contains good scavengers of these radicals. Two-year storage of bee pollen (frozen –18 °C and dried at room temperature) does not decrease total phenolic content, but it does decrease AOP of frozen bee pollen. Heat treatment affects the total phenolic content of bee pollen in some treatment regimes. Prolonged heat treatment has the effect of reducing total flavonoid content. Lyophilisation does not decrease the total phenolic content, total flavonoid content and AOP. Storing bee pollen extracts in light at room temperature for three months decreases total phenolic content in most of the extracts. Storing bee pollen extracts in a refrigerator (4 - 8 °C) for three months does not decrease the total phenolic content in most of the extracts.
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