Improved saccharification and ethanol yield from field-grown transgenic poplar deficient in cinnamoyl-CoA reductase.
Proc Natl Acad Sci U S A
; 111(2): 845-50, 2014 Jan 14.
Article
em En
| MEDLINE
| ID: mdl-24379366
ABSTRACT
Lignin is one of the main factors determining recalcitrance to enzymatic processing of lignocellulosic biomass. Poplars (Populus tremula x Populus alba) down-regulated for cinnamoyl-CoA reductase (CCR), the enzyme catalyzing the first step in the monolignol-specific branch of the lignin biosynthetic pathway, were grown in field trials in Belgium and France under short-rotation coppice culture. Wood samples were classified according to the intensity of the red xylem coloration typically associated with CCR down-regulation. Saccharification assays under different pretreatment conditions (none, two alkaline, and one acid pretreatment) and simultaneous saccharification and fermentation assays showed that wood from the most affected transgenic trees had up to 161% increased ethanol yield. Fermentations of combined material from the complete set of 20-mo-old CCR-down-regulated trees, including bark and less efficiently down-regulated trees, still yielded â¼ 20% more ethanol on a weight basis. However, strong down-regulation of CCR also affected biomass yield. We conclude that CCR down-regulation may become a successful strategy to improve biomass processing if the variability in down-regulation and the yield penalty can be overcome.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Populus
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Etanol
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Aldeído Oxirredutases
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Biocombustíveis
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Lignina
País/Região como assunto:
Europa
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article