Optimization and kinetic study of anthraquinone dye removal from colored wastewater using soybean seed as a source of peroxidase for environmental welfare

Abstract

As water contamination emerges as a serious threat to the environment, ventures for cleaner and sustainable solutions are continuously being developed. The present study investigates the ability of crude peroxidase extract from soybean seeds to degrade the anthraquinone dye Acid Violet 109. The influence of the essential parameters pH, dye concentration, hydrogen peroxide dosage, and temperature were inspected. The enzyme had 81.9 % biodegradation at pH 4 in 30 min with 0.1 U peroxidase, 40 mg/l dye concentration, and 1 mM hydrogen peroxide. Considering that substrate concentration can cause reaction inhibition, a kinetic study was performed. Kinetic data fitting using bisubstrate kinetics with a substrate inhibition model revealed the high inhibitory effect of the dye, which was confirmed by the inhibition constant, 7.123·10 –5 mM. Alongside the inhibition constant values, the Ping-Pong Bi-Bi model gave the maximum rates 15.788 and 14.321 mM/min for hydrogen peroxide and dye inhibition, respectively.