Gentisic acid molecule

Gentisic acid (2,5-dihydrobenzoic acid), found in gentian roots is used in cosmetics as a skin-whitening agent for the treatment of skin pigmentary disorders by influencing the synthesis of melanin through inhibition of melanosomal tyrosinase activity.

Its alkyl esters were investigated   as tyrosinase inhibitors in vitro and in cell cultures. The methyl ester of gentisic acid (2,5-dihidroxybenzoic acid; MG), a natural product of Gentiana's root, inhibits melanin synthesis in murine melanocytes at concentrations unable to induce cytotoxicity.

MG can act as pro-drug, inhibiting tyrosinase following the intracellular release of HQ, even if kinetic studies have demonstrated a direct effect on the enzyme, possibly through the binding of the copper ions.

Clinical trials have demonstrated the efficacy of the compound.