In conclusion, numerous advances have been made in the conversion of biomass to biofuels as biomass is the only source that is renewable and economically available. Problems associated with inhibitor generation and detoxification, fermentation of both hexoses and pentoses to ethanol, and the development of efficient microbial strains have partially been addressed. Simultaneous product recovery and process consolidation and integration will further improve the economics of production of biofuels from biomass. It is emphasized that numerous domestic and international companies have initiated their programs to commercialize conversion of biomass to biofuels. Separation and use of coproducts as additional sources for generating additional revenue can strengthen the approach further. 1

Acknowledgements

Nasib Qureshi would like to thank Adam Wallenfang for his help on finding information on published data. Nasib Qureshi and Stephen Hughes would like to thank Michael A. Cotta (U. S. Department of Agriculture, Peoria, IL) for reading this manuscript and providing critical comments.

Endnote

1. Mention of trade names or commercial products in this article is solely for the purpose of providing scientific information and does not imply recommendation or endorsement by the U. S. Department of Agriculture.

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