title: Ultrasounds pretreatment of olive pomace to improve xylanase and cellulase production by solid-state fermentation.
abstract: Olive mills generate a large amount of waste that can be revaluated. This work aim to improve the production lignocellulolytic enzymes by solid-state fermentation using ultrasounds pretreated olive mill wastes. The composition of olive mill wastes (crude and exhausted olive pomace) was compared and several physicochemical characteristics were significantly different. The use of both wastes in SSF was evaluated and a screening of fungi for xylanase and cellulase production was carried out. After screening, the use of exhausted olive pomace and Aspergillus niger led to the highest enzyme activities, so that they were used in the study of ultrasounds pre-treatment. The results showed that the sonication led to a 3-fold increase of xylanase activity and a decrease of cellulase activity. Moreover, the liquid fraction obtained from ultrasounds treatment was used to adjust the moisture of solid and a positive effect on xylanase (3.6-fold increase) and cellulase (1.2-fold increase) production was obtained.
authors.affiliation: CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Paulina
authors.initials: P
authors.lastname: Leite
authors.affiliation: CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: jmsalgado@uvigo.es.
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Salgado
authors.affiliation: CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Armando
authors.initials: A
authors.lastname: Venâncio
authors.affiliation: Department of Chemical Engineering, Sciences Faculty, University of Vigo (Campus Ourense), As Lagoas s/n, 32004 Ourense, Spain.
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Domínguez
authors.affiliation: CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Belo
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D001709:Biotechnology; D002480:Cellulase / Q000096:biosynthesis*; D002482:Cellulose / Q000737:chemistry; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis*; D005285:Fermentation; D019220:High-Energy Shock Waves; D006868:Hydrolysis; D007700:Kinetics; D008031:Lignin / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry; D031658:Olea / Q000737:chemistry*; D000069463:Olive Oil; D013010:Sonication; D013696:Temperature; D014465:Ultrasonics
chemical_list: D000069463:Olive Oil; C036909:lignocellulose; D002482:Cellulose; D008031:Lignin; D002480:Cellulase; D043364:Endo-1,4-beta Xylanases; D009584:Nitrogen
keywords: Cellulases; Olive pomace; Solid-state fermentation; Ultrasounds pre-treatment; Xylanases