Table 6.

Combination index (CI) value between mixtures consisting of two polyphenols on antiradical activity, n = 9.

Compound	Ferulic Acid	trans–Cinnamic Acid	Syringic Acid
Ferulic acid	-	0.63 ± 0.02 a Synergism	2.21 ± 0.06 b Antagonism
trans–cinnamic acid	0.63 ± 0.02 a Synergism	-	0.69 ± 0.03 a Synergism
Syringic acid	2.21 ± 0.06 b Antagonism	0.69 ± 0.03 a Synergism	-

Values are expressed as the mean ± SD; means with different letter superscripts (a,b) in the columns are significantly different (α = 0.05).