M. Abramson, O. Shoseyov, S. Hirsch, and Z. Shani

Abstract To date, most ethanolic fuel is generated from “first generation” crop feedstocks by conversion of soluble sugars and starch to bioethanol. However, these crops exploit land resources required for production of food. On the other hand, utilization of “second generation” lignocellulosic biofuels derived from the inedible parts of plants remains problematic as high energy inputs and harsh condi­tions are required to break down the composite cell walls into fermentable sugars. This chapter reviews and discusses genetic engineering approaches for the generation of plants modified to increase cellulose synthesis, enhance plant growth rates, cell wall porosity and solubility, as well as improve cell wall sugar yields following enzymatic hydrolysis. Strategies focusing on increased accessibility of cellulose­degrading enzymes to their substrates have been developed. These approaches reduce cell wall crystallinity or alter the hemicellulose-lignin complexes. A novel approach to cell wall modification involving the introduction of noncrystalline, soluble polysaccharides into cell walls is also presented. The use of such approaches may promote and accelerate the future use of lignocellulosic feedstocks for the bioethanol industry.

M. Abramson

The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, and The Otto Warburg Minerva Center for Agricultural Biotechnology, Faculty of Agricultural, Food and Environmental Quality Sciences,

The Hebrew University of Jerusalem, P. O. Box 12, Rehovot 76100, Israel

FuturaGene Ltd., 2 Pekeris Street, P. O. Box 199, Rehovot 76100, Israel

O. Shoseyov

The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, and The Otto Warburg Minerva Center for Agricultural Biotechnology, Faculty of Agricultural, Food and Environmental Quality Sciences,

The Hebrew University of Jerusalem, P. O. Box 12, Rehovot 76100, Israel

S. Hirsch • Z. Shani (H)

FuturaGene Ltd., 2 Pekeris Street, P. O. Box 199, Rehovot 76100, Israel e-mail: ziv@futuragene. com

J. W. Lee (ed.), Advanced Biofuels and Bioproducts, DOI 10.1007/978-1-4614-3348-4_18, 315

© Springer Science+Business Media New York 2013