Nordihydroguaiaretic acid has hydroxyl radical scavenging activity. - GreenMedInfo Summary
Mechanism of the OH radical scavenging activity of nordihydroguaiaretic acid: a combined theoretical and experimental study.
J Phys Chem B. 2010 May 20;114(19):6625-35. PMID: 20415502
Departamento de Química, División de Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana-Iztapalapa, 09340 City, México. firstname.lastname@example.org
The antioxidant nordihydroguaiaretic acid (NDGA) is a plant phenolic lignan originally isolated from the creosote bush (Larrea tridentata). It has been shown that NDGA scavenges efficiently hydroxyl radicals ((*)OH). In the present paper the mechanism by which NDGA scavenges (*)OH is addressed performing a combined experimental and theoretical investigation. We found that NDGA protects, in a concentration-dependent way, bovine serum albumin and DNA from the damage induced by (*)OH generated by the Fenton reaction. In addition, the NDGA + (*)OH reaction is predicted to be diffusion-controlled. The first step of this reaction is proposed to occur mainly by a sequential electron proton transfer from NDGA to (*)OH generating a neutral radical of NDGA, which after a second oxidation step gives a diradical that after a cascade sequential complex reaction produces a cyclic compound. This cyclic product is predicted to have a UV-vis spectrum very similar to that of NDGA, making its identification by this technique very difficult. The electrochemical studies performed in water support the formation of a cyclic compound (C2) as the main product of the reaction. It is concluded that NDGA can scavenge at least two (*)OH.