Intensification of α-amylase activity using ultrasound and its application for food waste hydrolysis

Abstract

The current research aims to study the ultrasound assisted intensification of activity of commonly applied amylase enzyme, under varying parameters like power, frequency, duty cycle, temperature and enzyme concentration. Two ultrasonic reactor configurations as bath and horn are used for comparing the efficacy of reactor configuration. The initial activity of native amylase was found as 5.77 U/g at optimum temperature of 35° C and pH 7. Under US bath treatment, α amylase attained maximum activity of 7.498 U/g at best treatment conditions of 120 W power, 30% duty cycle and 15 minutes of exposure time. In the case of US horn, application of 60 W power, 30% duty cycle, and 5 minutes of exposure increased the enzyme activity to 6.907 U/ g. Set of treatment approaches explored for obtaining highest yield of reducing sugars revealed the best approach of ultrasonic treatment of food waste followed by ultrasonic bath intensified amylase hydrolysis, yielding maximum amount of reducing sugars as 8.14 g/L in only 15 min. Overall the work elucidated the role of ultrasound in intensifying the enzyme activity as well as food waste hydrolysis maximizing the utilization of sustainable resource.