Compositional changes of wheat lignin by a fungal peroxidase analyzed by pyrolysis-GC-MS

Wheat-straw treatment with a Mn<sup>2+</sup>-oxidizing peroxidase from the ligninolytic fungus Pleurotus eryngii was investigated using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). Changes in the ratio between p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) lignin units...

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Detalles Bibliográficos
Autores: Camarero, Susana, Bocchini, Paola, Galletti, Guido C., Martínez, María Jesús, Martínez, Ángel T.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2001
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:dnet:digitalcsic_::2e8d1ff31604280d1e22372835c5e321
Acceso en línea:http://hdl.handle.net/10261/429091
https://api.elsevier.com/content/abstract/scopus_id/0035310660
Access Level:acceso abierto
Palabra clave:Lignocellulosics
Peroxidase
Phenolic content
Pleurotus eryngii
Pyroliyis
S/G ratio
Descripción
Sumario:Wheat-straw treatment with a Mn<sup>2+</sup>-oxidizing peroxidase from the ligninolytic fungus Pleurotus eryngii was investigated using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). Changes in the ratio between p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) lignin units were found, consistent with a degradation of S units and increase of the H content after enzymatic treatment. However, the most noticeable modification was the significant decrease of lignin phenolic content as revealed by Py-GC-MS of methylated straw. It was shown that 10 U of peroxidase per mg of straw decreased the amount of phenolic H units from 31% in the control to 3% in the treated straw, that of G units from 40 to 4%, and completely removed the small amount of phenolic S units present in wheat straw. The same tendency to decrease lignin phenolic content was observed when lower enzyme doses were used. These results provide conclusive evidence for modification of lignin during in vitro treatment of a natural lignocellulosic substrate with a ligninolytic peroxidase. © 2001 Elsevier Science B.V.