ABSTRACT
High uncertainty and fragile nature of the fossil fuel-based global economy and the environment issues of global warming have highlighted the importance of biomass-based biofuel production for both sustainable energy economy and climate change mitigation. Among the biofuels, bioethanol has the most promising attraction and importance as a next generation liquid biofuel for automobile. Its industrialization has been proved to be practical in several countries and present annual global bioethanol production has reached 86.9 billion liters. However, the main drawback of the current production system is that it abundantly consumes starch and sugar as raw materials, and competes with arable land and food production, finally leading to intense food scarcity in the world (Ogg, 2009; Bastianoni and Marchettini, 1996). Therefore, production of bioethanol from cellulose, which does not compete with food stock, is desired.
