The hydroperoxyl and superoxide anion radical scavenging activity of anthocyanidins in physiological environments: Theoretical insights into mechanisms and kinetics. (December 2021)

• Record Type: Journal Article
• Authors: Vo, Quan V.; Hoa, Nguyen Thi; Thong, Nguyen Minh; Mechler, Adam
• Is Part Of: Phytochemistry. Volume 192(2021)
• Publication Date: 2021-12
• Subjects: Anthocyanidin -- Antioxidant -- Superoxide -- Rate constant -- Kinetics -- Radical scavenging; Botanical chemistry -- Periodicals; Biochemistry -- Periodicals; Botany -- Periodicals; Chimie végétale -- Périodiques; 572.2
• DOI: 10.1016/j.phytochem.2021.112968
• Languages: English
• ISSNs: 0031-9422

Abstract

Abstract: The HOO and O2 − scavenging activities of 12 natural anthocyanidins were investigated in physiological environments by using DFT calculations. The results suggest high HOO scavenging activity in aqueous medium with overall rate constants in the range of k overall = 1.58 × 10 8 − 7.59 × 10 9 M −1 s −1, whereas in lipid medium only weak activity is predicted. O2 − scavenging is also fast in water with k app = ∼10 9 M −1 s −1 . Like in the case of many other antioxidants that contain acidic moieties, the anion states (H3 A − and H2 A 2− ) and the single electron transfer mechanism play a dominant role in the HOO scavenging activity of anthocyanidins in water at pH = 7.4. Analysis of the mechanism suggests that the O2 − and HOO radical scavenging can occur as a regeneration cycle that might increase the protective efficiency of anthocyanidins against oxidative stress. Graphical abstract: Short text : Quantum chemistry calculations suggest that anthocyanidins are excellent HOO and O2 − radical scavengers in water with k overall = 10 8 − 10 9 M −1 s −1 . Image 1 Highlights: The anthocyanidins exhibit an excellent O2 . − and HOO antiradical activity in water The anion states played a dominant role in the HOO. scavenging activity. The SET mechanism defines the O2 . − and HOO radicals scavenging The O2 . − and HOO radicals scavenging can occur as a regeneration cycle The natural anthocyanidins are promising antioxidants in the physical environment .