Fungal hydrolysis and saccharification of rice straw and ethanol production.

摘要

Agricultural crop residues in Egypt have been estimated to amount, 30-35 millions ton/year. Rice, as one of the main agricultural crops in Egypt, amounts to 3.6 million tons rice straw/year. Uncontrolled open burning of rice straw causes severe air pollution, which peaks every year in autumn season, creating an episode known as the black cloud period. In an attempt to entail many environmental and developmental benefits, this study was performed on rice straw as a resource for production of cellulases enzymes and bioethanol. Solid state fermentation SSF of rice straw by locally isolated fungal strains Trichoderma viride F-94 and Aspergillus terreus F-98 produced good yield of endo-glucanase CMCase 161 IU/mL and 232 IU/mL and exo-glucanase FPase 76 IU/mL and 80 IU/mL, respectively. Separate hydrolysis and fermentation SHF of ground and steam pretreated rice straw by T. viride F-94 and Candia tropicalis Y-26 or Saccharomyces cerevisiae Y-39 produced 50 and 39 gallons ethanol/ton rice straw, respectively. While that, in case of SHF by A. terreus F-98 and C. tropicalis Y-26 or S. cerevisiae Y-39 ~ 38 and 45 gallons ethanol/ton rice straw were produced, respectively.