Effect of microwave radiation on the activity of catalase. decomposition of hydrogen peroxide under microwave and conventional heating

Abstract

The effect of microwave heating (MW) on the activity of a well-known enzyme (catalase) was elucidated by examining the catalase-assisted decomposition of hydrogen peroxide (H₂O₂ at various heating times (0 to 12 min)). For comparison, conventional water bath heating (WB) was also examined under identical temperature conditions. Microwave radiation had a positive effect on the activity of catalase only over a very short time (less than 3 min), presumably because of the possible disruption of the catalase structural integrity under microwave irradiation at longer times (a negative influence) as evidenced by Gel Permeation Chromatographic (GPC) and MALDI Time-Of-Flight-Mass-Spectrometric (MALDI-TOFMS) analyses. The effect of temperature on the catalase activity was also probed at 39, 37, and 25 °C. Results indicate that utilizing a hybrid heating approach with conventional heating (water bath) coupled to microwaves was more effective provided microwave irradiation was carried out for a short time (also less than 3 min). Moreover, it is demonstrated that microwave heating in degrading hydrogen peroxide was most effective when the enzymatic reaction was carried out at a lower temperature, particularly at 25 °C.