The inherent conflict between the increase of global energy
demand and the depletion of fossil fuel reserves, along with the
environmental concerns caused by the extensive use of fossil fuels,
has necessarily called for sustainable energy alternatives [1]. Using
biomass for liquid biofuels production has sparked the interest
worldwide due to its abundance, renewability and carbon
neutrality [2]. However, today, the major viable commercial options
for producing liquid biofuels use edible crops (vegetable oils for
biodiesel and corn/sugarcane for bioethanol), which has negative
impacts on food and feed supplies [2,3]. Research efforts are,
therefore, re-orientated to use the biological waste such as agricultural
and forest residues, animal manure, food processing waste
and municipal waste [4e10]. Utilizing waste streams for biofuels
production also has additionally environmental benefits, including
reducing the local pollution, decreasing greenhouse gas emissions,
and lessening the burden on landfills.