Antioxidant and Neuroproliferative Effects of THL-3-PTD5 Peptide Derived from Hydramacin-1 Antimicrobial Peptide

Table 3

Comparison of antioxidant activity of the alanine-scanning THL-3 peptide in both the ABTS and DPPH radical scavenging assay.

Peptide	Difference of EC50^a (μM)		Total^c
	ABTS	DPPH
THL-3	0	0	0
THL-3-A1	−13.9	14.8	0.9
THL-3-A2	−6.3	15.7	9.4
THL-3-A3	−4.6	−7.2	−11.8
THL-3-A4	8.8	8.7	17.5
THL-3-A5	N.D.^b	N.D.^b	−100
THL-3-A6	−51.3	17.7	−33.6
THL-3-A7	−56.3	−16.8	−73.1
THL-3-A8	−14.7	0.2	−14.5
THL-3-A9	−34.7	7.8	−26.9
THL-3-A10	−37.6	17.3	−20.3

^aDifference of EC₅₀ was calculated using the following formula: EC₅₀ (THL-3) − EC₅₀ (sample). ^bN.D. indicates that the antioxidant activity of the peptide was not detected, and a value of −50 was used to calculate the total difference. ^cThe total difference value of less than −20 indicates that the original amino acid plays more important roles in the antioxidant activity of THL-3.