Horseradish Peroxidase-Mediated Synthesis of an Antibacterial Gallic Acid-g-Chitosan Derivative and Eco-friendly Dyeing of Silk Fabric

In this study, gallic acid- g -chitosan colored complexes were produced using the HRP-catalyzed method and successfullyused to dye silk fabrics. The reaction mechanism was studied using FT-IR, 1 H-NMR, and ESI-MS technologies; the dyedsilk fabrics were characterized through K/S , color fastness, and antibacterial tests. In addition, an in situ staining processbased on enzyme catalysis was explored to simplify the pretreatment process of chitosan. Chitosan and gallic acid werepolymerized through O–Ph, Ph–Ph and amino-phenyl bonds to form a dark-yellow polymer that was successfully used todye silk fabrics. In addition, signifi cant color diff erences were observed between fabrics dyed without chitosan and dyed inthe presence of chitosan. As a result, gallic acid- g -chitosan dyes polymerized via HRP catalysis improved the antimicrobialproperties of the colored fabrics without signifi cantly aff ecting the color fastness of the silk fabrics.