# Antioxidant Power of Vitexin and Isovitexin Against OOH Radicals: A Comparative Theoretical Investigation

## TL;DR

This study compares the antioxidant abilities of vitexin and isovitexin against OOH radicals using theoretical methods.

## Contribution

The paper provides a comparative theoretical investigation of the antioxidant mechanisms of vitexin and isovitexin in different environments.

## Key findings

- Vitexin and isovitexin show similar antioxidant activity with rate constants of 1.45 × 10³ M⁻¹ s⁻¹ and 4.78 × 10³ M⁻¹ s⁻¹ respectively.
- Their radical scavenging capacities are slightly lower than Trolox in both aqueous and lipid-like environments.

## Abstract

The antioxidant activity of vitexin and isovitexinflavonoids
widely found in various plants and used in traditional medicinehas
been theoretically evaluated against the OOH radical. Multiple reaction
mechanisms, including hydrogen atom transfer, single electron transfer,
and radical adduct formation, were considered. The study accounts
for all species present in aqueous solution at physiological pH as
well as in lipid-like environments. Both compounds exhibit similar
antioxidant activities, with apparent rate constants of 1.45 ×
103 M–
1 s–
1 for vitexin and 4.78 × 103 M–
1 s–
1 for isovitexin. Compared
to Trolox, a commonly used reference compound, their radical scavenging
capacities are slightly lower.