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Quantum Mechanical Predictions of the Antioxidant Capability of Moracin C Isomers.

ABSTRACT: The antioxidant capability of moracin C and iso-moracin C isomers against the OOH free radical was studied by applying density functional theory (DFT) and choosing the M05-2X exchange-correlation functional coupled with the all electron basis set, 6-311++G(d,p), for computations. Different reaction mechanisms [hydrogen atom transfer (HAT), single electron transfer (SET), and radical adduct formation (RAF)] were taken into account when considering water- and lipid-like environments. Rate constants were obtained by applying the conventional transition state theory (TST). The results show that, in water, scavenging activity mainly occurs through a radical addition mechanism for both isomers, while, in the lipid-like environment, the radical addition process is favored for iso-moracin C, while, redox- and non-redox-type reactions can equally occur for moracin C. The values of pKa relative to the deprotonation paths at physiological pH were predicted in aqueous solution.

SUBMITTER: Parise A

PROVIDER: S-EPMC8097241 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Quantum Mechanical Predictions of the Antioxidant Capability of Moracin C Isomers.

Parise Angela A De Simone Bruna Clara BC Marino Tiziana T Toscano Marirosa M Russo Nino N

Frontiers in chemistry 20210421

The antioxidant capability of moracin C and <i>iso</i>-moracin C isomers against the OOH free radical was studied by applying density functional theory (DFT) and choosing the M05-2X exchange-correlation functional coupled with the all electron basis set, 6-311++G(d,p), for computations. Different reaction mechanisms [hydrogen atom transfer (HAT), single electron transfer (SET), and radical adduct formation (RAF)] were taken into account when considering water- and lipid-like environments. Rate c ...[more]

PMID: 33968905

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