School of Chemical and Biotechnology, SASTRA University, Thanjavur, 613402, India.
Big bluestem and Giant reed grass were investigated as typical lignocellulosic substrates of low value for bioethanol production. The model substrates were pre-treated with acid catalysed steam explosion and alkaline peroxidation and then hydrolysed with 1.5% Hydrochloric acid at 120°C for 30 min at an acid to biomass ratio of 8:1. The hydrolysates were detoxified with oveliming combined with activated charcoal treatment and neutralised to pH 4.5. Acid hydrolysed substrates yielded reducing sugar at a concentration of 59.9 g/l and 65.8g/l for big bluestem and giant reed grass respectively. The fermentation of detoxified hydrolysates with Saccharomyces cereviseae yielded maximum ethanol at a concentration of 24.14 g/l with an efficiency of 76.90% for big bluestem and 27.38 g/l with an efficiency of 79.30% for giant reed grass. The overall results provided promising baseline information for the potential application of big bluestem and giant reed grass as lignocellulosic feedstock for bioethanol production.
bioethanol, lignocellulosic substrates, acid catalysed steam explosion, Alkali peroxidation, dilute acid hydrolysis, overliming, Saccharomyces cerevisiae