Conventional and supercritical extraction of phenolic compounds from Brazilian red and green propolis

Abstract

The extracts of green propolis and red propolis from Brazil were evaluated. The extracts were obtained by extraction with ethanol, methanol, water, hexane (soxhlet) and supercritical CO2 at 50ºC/300 bar. Fractionation of the red propolis ethanolic extract (EEP) with scCO2 at temperatures of 40–60ºC and pressures of 200–400 bar was also evaluated. Methanolic extraction was the best method in terms of yield for both green and red propolis. Moreover, fractionation of the red propolis ethanolic extract with scCO2 produced fractionated extracts with much higher flavonoid contents than those found in the original EEP extract.