The DPPH radical scavenging activity of methylated PLFP and
purified PLFP were determined to evaluate their antioxidant activities.
As shown in Fig. 1, the DPPH radical scavenging activity of the
purified PLFP was 22.1%, significantly (P < 0.05) higher than all the
methylated PLFP samples. From the results obtained in this study, a
high volume of methyl iodide represented a high degree of methylation
for PLFP. By increasing the degree of methylation, the DPPH
radical scavenging activity decreased. However, no further decrease
was observed when the volume of methyl iodide increased
in the range of 0.2–0.8 ml. The correlation coefficient between degree
of methylation and DPPH radical scavenging activity was
determined to be 0.72.