English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/39898
Title: Isolation of high-purity residual lignins from eucalypt paper pulps by cellulase and proteinase treatments followed by solvent extraction
Authors: Ibarra, David; Río Andrade, José Carlos del ; Gutiérrez Suárez, Ana ; Rodríguez García, Isabel María; Romero Sánchez, Javier; Martínez Hernández, María Jesús; Martínez, Ángel T.
Keywords: Cellulase
Paper pulp
Eucalyptus globulus
Totally chlorine free bleaching
Infrared spectroscopy
Analytical pyrolysis
Issue Date: 2004
Publisher: Elsevier
Citation: Enzyme and Microbial Technology 35:173-181 (2004)
Abstract: In the context of environmentally-friendly bleaching in paper pulp manufacturing, an enzymatic procedure was developed for the isolation of residual lignins from eucalypt pulp. The method was based on the hydrolysis and complete solubilization of pulp cellulose using a combination of Trichoderma cellulase and Aspergillus beta-glucosidase, followed by lignin purification using Bacillus protease (for hydrolysis of contaminating cellulase) and extraction of lignin with dimethylacetamide and NaOH. This method was applied to both unbleached and totally chlorine free bleached eucalypt kraft pulps. The different fractions obtained were analyzed by Fourier-transform infrared spectroscopy and pyrolysis-gas chromatography/mass spectrometry to evaluate the effect of the different isolation steps, and optimize the lignin isolation procedure. Depending of the type of pulp and its delignification degree most of the lignin was recovered from the cellulase hydrolyzate or the non-hydrolyzable residue. High-purity lignins were obtained from pulps by a new isolation procedure that included double solvent purification after combining the two fractions from protease treatment. This method is being used to analyze the effect of chlorine-free reagents (including enzymes) in clean bleaching sequences.
Description: aCentro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain bInstituto de Recursos Naturales y Agrobiología, CSIC, PO Box 1042, E-41080 Sevilla, Spain cENCE, CIT, Carretera de Campañó s/n, E-36157 Pontevedra, Spain
URI: http://hdl.handle.net/10261/39898
DOI: http://dx.doi.org/10.1016/j.enzmictec.2004.04.002
Appears in Collections:(IRNAS) Artículos
(CIB) Artículos
Files in This Item:
File Description SizeFormat 
2004-Ibarra-EMT-35-173.pdf178 kBAdobe PDFThumbnail
Show full item record

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.