Thermochemical behavior of sorghum procyanidin trimers with C4–C8 and C4–C6 interflavan bonds in the reaction with superoxide anion radical and H2O2-forming NADH-oxidase flavoenzyme

• Published in: Computational and theoretical chemistry 2020-09, Vol.1186, p.112912, Article 112912
• Main Authors: Mendoza-Wilson, Ana María, Balandrán-Quintana, René Renato, Cabellos, José Luis
• Format: Article
• Language: English
• Subjects: DFT; NADH-oxidase; Procyanidin; Sorghum; Superoxide anion radical
• ISSN: 2210-271X
• DOI: 10.1016/j.comptc.2020.112912

[Display omitted] •CDPTET mechanism does not seem to be viable in the reaction of SPT against O2−.•SPT2 with interflavan bonds C4–C8 and C4–C6 has great potential to inhibit the O2−.•SPLET mechanism could operate in the reaction of SPT2 against O2− in aqueous media.•SPT2 could prevent binding of NAD(P)H to the H2O2-forming NADH-oxidase flavoenzyme. The thermochemical behavior of four sorghum procyanidin trimers (SPT) with C4−C8 and C4−C6 interflavan bonds, in the reaction with O2− via the concerted double proton-transfer electron-transfer (CDPTET) and sequential proton-loss electron-transfer (SPLET) mechanisms, as well as with a H2O2-forming NADH-oxidase flavoenzyme, were analyzed by computational methods. Our results revealed that both CDPTET and SPLET mechanisms could be viable to develop in an aqueous medium. However, the free energies and rate constants of reaction showed that SPLET could be more favored. The SPT2 with interflavan bonds C4–C8 and C4–C6 in its most stable and predominant conformation (Compact-Extended), reached apparent rate constants of 1.07 × 106 (CDPTET) and 9.8 × 106 (SPLET) to scavenge the O2− in aqueous media. Likewise, SPT2 could prevent binding of NAD(P)H to the NADH-oxidase flavoenzyme, suggesting the greatest potential of this procyanidin to prevent the production and activity of the O2− in aqueous media.