DPPH radical scavenging activity was determined by
DPPH assay using the method of Shimada et al. (1992) and
Binsan et al. (2008). Sample (1.5 ml) was added to 1.5 ml of
0.15 to mM DPPH in 95% ethanol. The mixture was mixed
vigorously and allowed to stand at room temperature in the
dark for 30 min.