Renewable Energy, Vol.103, 701-707, 2017
Ethanol production from lignocellulosic substrate Prosopis juliflora
Delignification of Prosopis juliflora at 10 g, 100 g and 1 kg level at 1:10 ratio using 2% (w/v) Na2S2O4 at 30 +/- 2 degrees C for 18 h resulted in removal of 82.16 +/- 0.34%, 81.82 +/- 0.36% and 79.23 +/- 0.25% of lignin, respectively. By subsequent biphasic dilute acid hydrolysis of substrate, 51.4 +/- 0.47%, 51.2 +/- 0.52% and 48.1 +/- 0.18% of holocellulose was hydrolyzed with release of 1.94 +/- 0.03 g/L, 2.16 +/- 0.10 g/L and 1.68 +/- 0.05 g/L. phenolics and 1.17 +/- 0.02 g/L, 1.10 +/- 0.03 g/L and 1.07 +/- 0.04 g/L of furans, respectively. Later, detoxification of hydrolysates removed 85.83 +/- 2.8% of phenolics, 87.85 +/- 2.4% of furans with sugar loss of 4.74 +/- 0.12%. Enzymatic hydrolysis of substrate yielded 39.37 +/- 0.92 g/L, 3737 +/- 0.8 g/L and 30.07 +/- 0.48 g/L of sugars, respectively. Further, fermentation of mixture of acid and enzyme hydrolysate at 100 g level of substrate using co culture-c (Saccharomyces cerevisiae VS3 and Pichia stipitis NCIM 3498) produced 10.85 g/L of ethanol with fermentation efficiency, ethanol yield and productivity of 87.34 +/- 0.28%, 0.445 +/- 1.32 g/g and 0.301 +/- 0.011 g/L/h, respectively. (C) 2016 Elsevier Ltd. All rights reserved.