Ultrasound assisted enzymatic hydrolysis of sucrose catalyzed by invertase: Investigation on substrate, enzyme and kinetics parameters

Abstract

This work studied the ultrasound technology as an alternative to enhance the reaction of sucrose inversion. To achieve it, the effect of ultrasound processing was evaluated in three situations: the reaction (invertase acting on substrate under ultrasound processing), the isolated substrate (sucrose) and the isolated enzyme (invertase). Ultrasound (25 kHz, 22 W/L) processing was conducted under different conditions of pH and temperature. The ultrasound assisted reaction was accelerated in relation to the conventional processing. This process increased the sucrose hydrolysis rate up to 33% at 40 °C, and 30% at 30 °C. The ultrasound as a pre-treatment method did not promote sucrose hydrolysis, but slightly reduced the invertase activity, independently of the pH and temperature of evaluation. Sonication also increased Vmax (increased of 23%) and maintained constant Km, indicating that the ultrasound accelerated mass transfer during the reaction, but did not directly affected the enzyme. In addition, the invertase catalytic efficiency enhanced 27% under sonication. Therefore, ultrasound technology emerges as an interesting alternative to improve the invertase performance, accelerating enzymatic reaction.