Quenching of DPPH
The free radical-scavenging capacity of propolis extract (with and without CAPE),
CAPE and galangin was tested by their ability to bleach the stable 1,1-diphenyl-2-
picryl-hydrazyl radical (DPPH) w20x. The reaction mixture contained 86 mM DPPH
and different concentrations of propolis extract (with and without CAPE) (12, 25
and 50 mgyml), CAPE (0.6, 1.2 and 2.5 mM) and galangin (20, 50 and 100 mM)
in 1 ml of ethanol. After 10 min at room temperature the absorbance at ls517 nm
was recorded.