But, at higher concentrations,
such as 1000, 2000 and 3000 lg/ml, TBSF melanin and
synthetic melanin showed statistically similar scavenging activities.
IC50 values were 1879 ± 90.9 lg/ml for TBSF melanin and
2044 ± 67.9 lg/ml for synthetic melanin. These results indicated
that the ability of TBSF melanin to scavenge superoxide radical is
slightly stronger than that of synthetic melanin.