The role of seasonality on the chemical composition, antioxidant activity and cytotoxicity of Polish propolis in human erythrocytes

ABSTRACT Propolis extracts possess beneficial biological effects, such as antioxidant activity. However, the composition of propolis and biological properties of its extracts depend on many factor, including time of harvesting. The main purpose of this study was to evaluate the seasonal effect on the phenolic profile of Polish propolis extracts and their antioxidant activity. Propolis samples were collected from the same apiary during three seasons of the year. The chemical composition (contents of phenolic acids and flavonoids) of ethanolic propolis extracts was determined by ultra-performance liquid chromatography equipped with a photodiode detector and a triple quadrupole mass spectrometer. The antioxidant potential of propolis extracts was evaluated. Additionally, in vitro effects of propolis extracts on the morphology of human red blood cells and the selective permeability of their membrane were determined. The capacity of propolis extracts to protect human red blood cells against free radical-induced hemolysis was also studied. The analyze of the chemical composition of propolis extracts collected in three season of the year indicated that the sum of determined flavonoids and phenolic acids was the highest in the sample harvested in the spring (125.14 mg/g) and it was the lowest in the extract of material collected in the fall (110.09 mg/g), but the differences were slightly. The concentration of examined phenols in propolis samples collected in different seasons was si...
Source: Revista Brasileira de Farmacognosia - Category: Drugs & Pharmacology Source Type: research