Propolis Drops as Evidence for Dilution of Propolis by Honey Bees?

Introduction Propolis is a sticky resinous substance collected from buds, leaves, stems of wild plants and processed by bees, which has bactericidal properties and which they use to seal cracks in the hive, polish the walls of wax cells, embalm enemy corpses (mice, reptiles, etc.) (DSTU 4662:2006, 2007). Considering the propolis properties, it is widely used in the food, pharmaceutical and other industries (Gülşah et al., 2020; Özer, 2020; Safaei & Azad, 2020; Sahlan et al., 2020). The botanical plant origin of propolis has been proven by numerous studies that have lasted since the last century (Bankova et al., 2006; Ghisalberti, 1979; Popravko, 1976). Each geographical zone has a large number of plants that produce secondary metabolites with antimicrobial effects and different chemical composition and may be potential sources of propolis. However, honey bees choose a narrow list of plants from which resins are collected to produce propolis.