Effect of Alkyl Chain Length and Hydroxyl Substitution on the Antioxidant Activity of Gallic Acid Esters.

ABSTRACT: Gallic acid (GA) exhibits excellent antioxidant properties but suffers from chemical instability due to its carboxyl group, which limits practical application. To address this, we designed and investigated 14 distinct ester derivatives of GA, which were categorized into two major groups based on their substituents: chain alkyl and hydroxyl-substituted alkyl groups. Systematic evaluation revealed a striking decline in the DPPH radical scavenging activity of alkyl esters with increasing carbon chain length, from 91.9% for GA-C3 to 55.6% for GA-C30. The hydroxyl-functionalized GA esters GA-EG, GA-GL, and GA-PT maintain high antioxidant activity (>90%) while improving applicability through carboxyl substitution. In the oil system, all derivatives significantly prolong the oxidation induction t

SUBMITTER: Chen Q 

PROVIDER: S-EPMC12844035 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature