Chemical characterization of the bee pollen samples collected from samsun and Rize (Black Sea region/Turkey) and investigation of their antimicrobial and antioxidant activities

Bee products (honey, pollen, propolis etc.) have been used throughout history to protect health and treat diseases. Among them, bee pollen is one of the valuable products in Apitherapy produced by honeybees (Apis mellifera L.). Although bee pollen is considered as a bee product, it is mainly composed of pollen grains from plant anthers which honeybees enzymatically alter or stick together by using nectar. Accordingly, there are 2 types of bee pollen, i.e. monofloral (composed of pollen from one plant species) and multifloral pollen (composed of different plant species and thus shows variable properties). In this study, botanical origins of different bee pollen samples collected from Black Sea Region in Turkey were determined by microscopic examination. Accordingly, five of them were found as monofloral bee pollen. Later, phenolic profiles of these samples were evaluated by using a high-performance thin-layer chromatographic (HPTLC) method. Galangin, Caffeic acid Phenethyl Ester (CAPE), Caffeic acid, Chyrsin, Quercetin, Isoquercitrin and Rutin were commonly found in the investigated samples. Moreover, comparative antimicrobial activity against strains of Streptococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans resulted that PO2 and PO9 botanically originated from Brassicaceae (37%) and Rosaceae (35%) respectively, had the highest antimicrobial activity, minimum inhibitory concentration was found as 64 μg/mL. Lastly, total phenol content (TPC), total flavonoid content (TFC) and DPPH (2,2-diphenyl-1-picrylhydrazyl) test to determine antioxidant activity were performed. As a consequence, sample encoded as PO7 showed the highest TPC value (26.92 GAE/g), PO3 showed the highest TFC value (11.89 QE/g) and PO2 showed the highest antioxidant activity (22.93 TEAC/g).