Commercial cellulosic ethanol: The role of plant-expressed enzymes

  • Manuel B. Sainz
Invited Review


The use and production of biofuels has risen dramatically in recent yr. Bioethanol comprises 85% of total global biofuels production, with benefits including reduction of greenhouse gas emissions and promotion of energy independence and rural economic development. Ethanol is primarily made from corn grain in the USA and sugarcane juice in Brazil. However, ethanol production using current technologies will ultimately be limited by land availability, government policy, and alternative uses for these agricultural products. Biomass feedstocks are an enormous and renewable source of fermentable sugars that could potentially provide a significant proportion of transport fuels globally. A major technical challenge in making cellulosic ethanol economically viable is the need to lower the costs of the enzymes needed to convert biomass to fermentable sugars. The expression of cellulases and hemicellulases in crop plants and their integration with existing ethanol production systems are key technologies under development that will significantly improve the process economics of cellulosic ethanol production.


Biofuels Cellulosic ethanol Cellulases Pretreatment Biomass Enzymes 



Thanks to my colleagues Nancy Nye and Sherrica Morris for help in accessing references and to Karen Bruce, Terry Stone, John Steffens, Tom Bregger, Larry Gasper, and Scott Betts for helpful comments on the manuscript. My apologies to those colleagues whose publications I have not been able to include due to space constraints. The Syngenta Centre for Sugarcane Biofuels Development is supported by Syngenta, the Queensland University of Technology, Farmacule Bioindustries and by a grant from the National and International Research Alliances Program of the Queensland State government.


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Copyright information

© The Society for In Vitro Biology 2009

Authors and Affiliations

  1. 1.Syngenta Centre for Sugarcane Biofuels Development, Centre for Tropical Crops and BiocommoditiesQueensland University of TechnologyBrisbane QueenslandAustralia

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