Anti-inflammatory activity of gallic acid.

Gallic acid was found to possess antiinflammatory activity towards zymosan-induced acute food pad swelling in mice. In vitro studies on the mode of action of gallic acid revealed that this compound interferes with the functioning of polymorphonuclear leukocytes (PMNs). Scavenging of superoxide anions, inhibition of myeloperoxidase release and activity as well as a possible interference with the assembly of active NADPH-oxidase may account for the inhibition of inflammatory process by gallic acid. Structure-activity relationship analysis showed that the o-dihydroxy group of gallic acid is important for the inhibitory activity in vitro.