Oscillating Cellulase Adsorption and Enhanced Lignocellulose Hydrolysis upon Ultrasound Treatment

Abstract

We investigated the effects of ultrasound treatment on cellulase adsorption and lignocellulose hydrolysis. The activity of cellulase remained constant upon low-power ultrasound treatment (<120 W) and decreased using high-power ultrasound (>280 W). Oscillating cellulase adsorption occurred upon ultrasound treatment with any intensity. The maxima for desorption and adsorption were 41.9 and 83.1%, respectively, during 1 h of 90 W ultrasound treatment at 50 °C. A comparison between the short-time with long-time ultrasound experiments indicated that ultrasound treatment tended to desorb cellulase from substrate. However, ultrasound treatment also led to further surface erosion of biomass, which increased cellulase accessibility. These joint actions of ultrasound treatment induced the oscillating adsorption of cellulase. The increase in cellulase accessibility caused by ultrasound treatment led to a significant enhancement in lignocellulose hydrolysis.

Keywords

Lignocellulose / Cellulase / Ultrasound / Adsorption / Desorption / Hydrolysis

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