New Enzymatic Colorimetric Reactions of Benzoic Acid Derivatives with ABTS [2, 2'-Azino-di-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] in the Presence of Laccase

Abstract

New enzymatic colorimetric reactions of benzoic acid derivatives with 2, 2'-azino-di-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) in the presence of laccase are described. These laccase-catalyzed colorimetric reactions exhibited the characteristic colors arising from a strong absorption maximum in the visible region. Using these colorimetric reactions, benzoic acids e.g., 4-hydroxy-, 3-hydroxy-, and 3, 5-diamino-benzoic acids, could be determined in micromolar amounts. These methods will offer broad applicability to those enzymatic assays which are designed to release benzoic acids.