title: The application of ultrasound in the enzymatic hydrolysis of switchgrass.
abstract: In a series of experiments, untreated and ammonium hydroxide pretreated Klenow lowland variety switchgrasses are converted to reducing sugars using low-frequency (20 kHz) ultrasound and commercially available cellulase enzyme. Results from experiments using untreated and pretreated switchgrasses with and without ultrasound are presented and discussed. In untreated switchgrass experiments, the combination of ultrasound and enzymes resulted in an increase of 7.5% in reducing sugars compared to experiments using just enzymes. In experiments using ammonium hydroxide pretreated switchgrass, the combination of ultrasound and enzymes resulted in an increase of 9.3% in reducing sugars compared to experiments using just enzymes. Experimental evidence indicates that there is a synergistic effect from the combination of ultrasound and enzymes which lowers the diffusion-limiting barrier to enzyme/substrate binding and results in an increase in reaction rate. Scanning electron microscopic images provide evidence that ultrasound-induced pitting increases substrate surface area and affects reaction rate and yield.
authors.affiliation: Southern Regional Research Center, New Orleans, LA 70124, USA. Michael.Easson@ars.usda.gov
authors.forename: Michael W
authors.initials: MW
authors.lastname: Easson
authors.forename: Brian
authors.initials: B
authors.lastname: Condon
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Dien
authors.forename: Loren
authors.initials: L
authors.lastname: Iten
authors.forename: Ryan
authors.initials: R
authors.lastname: Slopek
authors.forename: Megumi
authors.initials: M
authors.lastname: Yoshioka-Tarver
authors.forename: Allan
authors.initials: A
authors.lastname: Lambert
authors.forename: Jade
authors.initials: J
authors.lastname: Smith
mesh_terms: D055162:Biocatalysis; D002480:Cellulase / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D006868:Hydrolysis; D010084:Oxidation-Reduction; D008897:Panicum / Q000737:chemistry*; D014465:Ultrasonics / Q000379:methods*
chemical_list: D002482:Cellulose; D002480:Cellulase