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Bee pollen has been used for many years in traditional medicine and supplementary nutrients. Bee pollen is mainly composed of nutrients and bioactive substances which might act as potential antioxidants and tyrosinase inhibitors. In this study, 14 species of monofloral bee pollen from China were collected to analyse their antioxidant and tyrosinase inhibitory properties. Our results revealed that virtually all the bee pollen samples possessed powerful antioxidant or tyrosinase inhibitory activities. These properties varied greatly depending on the fl oral species and extraction solvents. To extract phenolics of various species of bee pollen, the most effective solvent may be a solvent which is a 75 wt. % ethanol/water. Extracts of wuweizi, rape, phellodendron, apricot, and dandelion pollen had stronger antioxidant activities; on the other hand, those of apricot, camellia, and sunflower presented excellent tyrosinase inhibitory activities. In addition, we may have found a novel discovery: that apricot pollen exhibits both powerful antioxidant and strong tyrosinase inhibitory activities.

Phenolic compounds were extracted with food grade solvent of acidified aqueous ethanol from leaves, berries, berry press cakes, and branches of Finnish berry plants and analyzed with HPLC-DAD, UPLC-DAD-ESI-MS and NMR. In addition, press cakes from two berry species and branches from one species were also extracted and analyzed with the same methods. The antioxidant activities of the extracts were evaluated using Folin-Ciocalteau, oxygen radical absorbance capacity (ORAC), DPPH free radical scavenging, and total radical trapping antioxidant parameter (TRAP) assays. The antibacterial activities were investigated against various Gram-negative and Gram-positive foodborne pathogens. The leaf extracts showed higher antioxidative activities (3–20 fold in ORAC assay, 10–20 fold in TRAP) than the berry extracts, in association with the higher contents of phenolic compounds in the leaf extracts; Strongest anti-bacterial effects was observed in the leaf extracts of lingonberry (Vaccinium vitis-idaea), sea buckthorn (Hippophaë rhamnoides ssp. rhamnoides) and saskatoon (Amelanchier alnifolia) on Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus. However, the antibacterial efficacy varied with bacterial species and strains. The Folin-Ciocalteu, ORAC, and TRAP values was strongly correlated with the total content of flavonoids with less association shown with the content of total phenolics and flavonol glycosides. The results suggest a major contribution of pranthocyanidins and flavan‐3-ols to the antioxidative activities of the extracts. The growth inhibition on Staphylococcus aureus and Bacillus cereus was clearly associated with the content of total phenolics and ellagitannins.