Commercial and noncommercial peroxidases activity under ultrasound and microwave treatment: A pretreatment to improve wastewater treatment

Abstract

This study aimed at evaluating the activity of peroxidases after ultrasound and microwave radiation exposure as an alternative to the wastewater treatment improvement. The results showed that after treatment with ultrasound using a power of 30% and a temperature of 55 °C was obtained an increase in relative activity, 129.5% in the enzyme from rice bran, 147.9% in the enzyme from soybean meal and 102.4% in the enzyme from horseradish. Using microwave radiation, the highest relative activity (107.4%) was observed for the peroxidase extracted from rice bran with 10 seconds of reaction time and a reaction temperature of about 50 °C. The data obtained inthis study suggest that the ultrasonic bath and microwave are adequate for conducting reactions catalyzed by peroxidases because it was possible to increase their activity during the performed tests. Preliminary tests of enzyme application showed that the highest color removal occurred using 3 mL of the enzyme extract from rice bran and H2O2 concentrations of 40 mg L-1. This condition resulted in a color removal of about 40%.