Theoretical Study on the Antioxidant Activity of Natural Depsidones

Autor: Quan V. Vo, Duong Tuan Quang, Nguyen Khoa Hien, Nguyen Thi Hoa, Pham Cam Nam, Adam Mechler, Mai Van Bay
Rok vydání: 2020
Předmět:
Zdroj: ACS Omega
ACS Omega, Vol 5, Iss 14, Pp 7895-7902 (2020)
ISSN: 2470-1343
DOI: 10.1021/acsomega.9b04179
Popis: Depsidones are secondary metabolites in lichens with a range of potential health benefits. Among others, these compounds are believed to exhibit high hydroxyl radical and superoxide scavenging abilities, warranting a detailed investigation of their antioxidant properties. In this study, the radical scavenging activity of natural depsidones from Ramalina lichenized fungi was investigated in silico. Calculations of the thermodynamic parameters suggested that the main radical scavenging pathway follows the formal hydrogen transfer (FHT) mechanism; however, unexpectedly low rate constants were found in the CH3OO• scavenging reaction. Establishing that the depsidones are mostly ionized in an aqueous environment suggested that the single-electron transfer (SET) mechanism should not be ruled out. Consistently, depsidones were revealed to be excellent HO• and O2•– scavengers in aqueous solutions (k = 4.60 × 105 – 8.60 × 109 M–1 s–1 and k = 2.60 × 108 – 8.30 × 109 M–1 s–1, respectively) following the sequential proton loss electron transfer (SPLET) mechanism. These results suggest that natural fungal depsidones are potent hydroxyl and superoxide radical scavengers in aqueous solutions.
Databáze: OpenAIRE