Fractionation of ethanolic and hydroalcoholic extracts of green propolis using supercritical carbon dioxide as an anti-solvent to obtain artepillin rich-extract

Green propolis from southeastern Brazil is known for its potent biological activity and the presence of Artepillin-C. In order to obtain extracts concentrated in phenolic and artepillin-C compounds, supercritical carbon dioxide (scCO(2)) was used as an anti-solvent to selectively fractionate ethanolic and hydroalcoholic extracts of green propolis by precipitation in four separators in series. The fractions were evaluated for the global yield of each fraction and for the yields and concentrations of total phenolics (TP), total flavonoids (TF), 3,5-diprenyl-4-hydroxycinnamic acid (Artepillin C) (DHCA), 4-hydroxycinnamic acid (p-coumaric acid) (HCA) and 4-methoxy3,5,7-trihydroxyflavone (kaempferide) (MTHF) in the fractionated extracts, also evaluated was he antioxidant activity by DPPH. The scCO(2) was effective as an anti-solvent to obtain extract fractions rich in Artepillin C and with high antioxidant activity.