3.4. Total phenolic content versus radical scavenging
activity
Among the seven samples analyzed, the three methanolic
fractions showed a significant phenolic content
and radical scavenging activity. In general, extracts
or fractions with a high radical scavenging activity
showed a high phenolic content as well, but good correlations
could not be found among them (see Fig. 1).
A direct correlation between radical scavenging activity
and phenolic content of the samples was demonstrated
by linear regression analysis. The correlation
coefficient between total phenolics and DPPH and
between total phenolics and CL found to be 0.425
and 0.375, respectively. In general, the ethyl acetate
fraction showed the highest TPC and the highest
radical scavenging activity in both the tests of DPPH
and CL.
3.5. Comparison between the two methods of radical
scavenging activity
The magnitude of values for the successive extracts,fractions and residues showed a similar trend both in
the free radical and hydroxyl radical scavenging activities.
(see Fig. 2 and Table 2). A direct correlation between
the two methods of radical scavenging activity
was demonstrated by linear regression analysis. The
two methods showed a high correlation coefficient(0.9662).