Variation in Cell Wall Composition and Accessibility in Relation to Biofuel Potential of Short Rotation Coppice Willows
- 552 Downloads
Short rotation coppice (SRC) willow is currently emerging as an important dedicated lignocellulosic energy crop in the UK. However, investigation into the variation between species and genotypes in their suitability for liquid transport biofuel processing has been limited. To address this, four traits relevant to biofuel processing (composition, enzymatic saccharification, response to pretreatment and projected ethanol yields) were studied in 35 genotypes of willow including Europe’s leading SRC willow cultivars. Large, genotype-specific variation was observed for all four traits. Significant positive correlations were identified between the accessibility of glucan to enzymatic saccharification before and after pretreatment as well as glucose release and xylose release via acid hydrolysis during pretreatment. Of particular interest is that the lignin content of the biomass did not correlate with accessibility of glucan to enzymatic saccharification. The genotype-specific variations identified have implications for SRC willow breeding and for potential reductions in both the net energy expenditure and environmental impact of the lignocellulosic biofuel process chain. The large range of projected ethanol yields demonstrate the importance of feedstock selection based on an ideotype encompassing the performance of both field biomass growth and ease of conversion.
KeywordsBiofuel Composition Enzymatic saccharification Accessibility Willow (Salix) Cell wall sugars
We are grateful for financial support for this research from the BBSRC Sustainable Bioenergy Centre (BSBEC), working within the BSBEC BioMASS (http://www.bsbec-biomass.org.uk/) Programme of the centre. Further funding support from the Rothamsted Bioenergy and Climate Change Institute Strategic Programme Grant and from the Porter Alliance (http://www.porteralliance.org.uk) was provided for a studentship awarded to N.J.B. Brereton. The authors would also like to thank William MacAlpine, Tim Barraclough and March Castle for their assistance in harvesting and measuring the trees used in this work. Rothamsted Research receives grant aid from the Bio-technology and Biological Sciences Research Council (BBSRC).
- 13.EU RED Directive 2009/28/EC (2009). Official Journal of the European Union L 140/16 (Brussels): Belgium: European CommissionGoogle Scholar
- 14.RFA (2009) The Renewable Transport Fuel Obligations Order 2007 (as amended). RFA. http://www.renewablefuelsagency.gov.uk/sites/renewablefuelsagency.gov.uk/files/_documents/RTFO_Order_as_amended_April_2009.pdf
- 16.Serapiglia MJ, Cameron KD, Stipanovic AJ, Smart LB (2009) Analysis of biomass composition using high-resolution thermogravimetric analysis and percent bark content for the selection of shrub willow bioenergy crop varieties. BioEnerg Res 2(1–2):1–9. doi: 10.1007/s12155-008-9028-4 CrossRefGoogle Scholar
- 28.Hames B, Ruiz R, Scarlata C, Sluiter A, Sluiter J, Templeton D (2008) Preparation of Samples for Compositional Analysis. Laboratory Analytical Procedure (LAP). National Renewable Energy Laboratory NREL,Google Scholar
- 29.Sluiter A, Ruiz R, Scarlata C, Sluiter J, Templeton D (2005) Determination of Extractives in Biomass. Laboratory Analytical Procedure (LAP). National Renewable Energy Laboratory NREL,Google Scholar
- 30.Sluiter A, Hames B, Ruiz R, Scarlata C, Sluiter J, Templeton S et al (2008) Determination of Structural Carbohydrates and Lignin in Biomass. Laboratory Analytical Procedure (LAP). National Renewable Energy Laboratory NREL,Google Scholar
- 31.Selig M, Weiss N, Ji Y (2008) Enzymatic Saccharification of Lignocellulosic Biomass. Laboratory Analytical Procedure (LAP). National Renewable Energy Laboratory NREL,Google Scholar
- 33.GenStat® (2008) © Lawes Agricultural Trust Rothamsted Research, 11th edn. VSN, UKGoogle Scholar
- 46.RoyalSociety (2008) Sustainable biofuels: prospects and challenges. The Royal Society, 6–9 Carlton House TerraceGoogle Scholar