Investigating the antioxidant mechanism of violacein by density functional theory method

Violacein possesses a significant antioxidant activity, which possible relates to its other biological functions. In this study, the hydrogen atom transfer and electron donating ability of violacein is studied by using density functional theory method. The structure of violacein is optimized, and its O-H and N-H bond dissociation energy (BIDE), ionization potential (IP) are calculated. The results find violacein has a strong electron donating ability, but a weak hydrogen atom transfer ability. While, its coplanar isomers have the strong hydrogen atom transfer ability as well as electron donating ability. The N7-H7 band plays an important role in violacein's antioxidant activity. (C) 2007 Elsevier B.V. All rights reserved.