title: Sequential low and medium frequency ultrasound assists biodegradation of wheat chaff by white rot fungal enzymes.
abstract: The consequences of ultrasonic pre-treatment using low (40 kHz) and medium (270 kHz) frequency (40 kHz followed by 270 kHz) on the degradation of wheat chaff (8 g 100ml(-1) acetate buffer, pH 5) were evaluated. In addition, the effects of the ultrasonic pre-treatment on the degradation of the wheat chaff when subsequently exposed to enzyme extracts from two white rot fungi (Phanerochaete chrysosporium and Trametes sp.) were investigated. Pre-treatment by sequential low and medium frequency ultrasound had a disruptive effect on the lignocellulosic matrix. Analysis of the phenolic-derived volatiles after enzymatic hydrolysis showed that biodegradation with the enzyme extract obtained from P. chrysosporium was more pronounced compared to that of the Trametes sp. The efficacy of the ultrasonic pre-treatment was attributed to increased enzyme accessibility of the cellulose fibrils due to sonication-induced disruption of the plant surface structure, as shown by changes in the microstructure.
authors.affiliation: CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, VIC 3030, Australia.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Oliver
authors.affiliation: CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, VIC 3030, Australia.
authors.forename: Raymond
authors.initials: R
authors.lastname: Mawson
authors.affiliation: Food Science, School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Melton
authors.affiliation: CSIRO Material Science and Engineering, Normanby Road, Clayton, VIC 3168, Australia.
authors.forename: Geoff
authors.initials: G
authors.lastname: Dumsday
authors.affiliation: CSIRO Material Science and Engineering, Normanby Road, Clayton, VIC 3168, Australia.
authors.forename: Jessica
authors.initials: J
authors.lastname: Welch
authors.affiliation: CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, VIC 3030, Australia.
authors.forename: Peerasak
authors.initials: P
authors.lastname: Sanguansri
authors.affiliation: CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, VIC 3030, Australia.
authors.forename: Tanoj K
authors.initials: TK
authors.lastname: Singh
authors.affiliation: CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, VIC 3030, Australia. Electronic address: Maryann.augustin@csiro.au.
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Augustin
mesh_terms: D001673:Biodegradation, Environmental; D008031:Lignin / Q000737:chemistry* / Q000378:metabolism*; D020075:Phanerochaete / Q000201:enzymology*; D013010:Sonication; D055454:Trametes / Q000201:enzymology*; D014908:Triticum / Q000737:chemistry* / Q000378:metabolism
chemical_list: C036909:lignocellulose; D008031:Lignin
keywords: Biodegradation; Phanerochaete chrysosporium; Trametes sp.; Ultrasound; Wheat chaff; White rot fungal enzymes