Proximate Composition and Antioxidant Activity of Honey Bee Collected Pollen in the Main Flowering Season, in West Shewa Zone, Central Ethiopia

Abstract

Abstract This study aimed to assess the effect of botanical and geographical differences on the protein, minerals, total phenolic content and the antioxidant activity of bee pollen collected from five districts in West Shewa Zone, Ethiopia. Pollens of Guizotia sp., Brassica sp., Trifolium sp., Eucalyptus sp., Plantago lanceolata and Vicia faba were color-sorted from multifloral pollens and subjected to chemical analysis. The results revealed the mean content of moisture 10.6% of fresh weight (FW), protein 19.4% of dry weight (DW) and ash 2.4% (DW); the most dominant minerals, K (9765.6), Ca (963.4), Mg (960.5), Fe (142.8) and P (126.5) in mg/kg DW. The average of the total phenolic content (TPC) and the antioxidant activity (DPPH radical) were 40.3 GAE mg/g FW and 13.7 AAE mg/g FW (gallic and ascorbic acid equivalent, respectively). V. faba pollen had the highest protein, ash, P and Cu content. Four pollen taxa had the highest Ca values, while multifloral pollens contained the highest Fe content. The samples from Ejere had the highest ash, Ca, Na and Cu content. The results showed a high content of the tested chemicals and a strong antioxidant capacity of bee pollen, varying with botanical and geographical origins. These findings would also serve as inputs for further assessment of the nutritional values of pollen for honey bee colonies and potential human consumption. However, comprehensive chemical investigations of larger number of samples representing diversified flora and locations are crucial to developing a broad regional information base on the nutritional profile of bee pollen.