Mixing of acid and base pretreated corncobs for improved production of reducing sugars and reduction in water use during neutralization.
Pretreatment of biomass for bioethanol production makes it necessary to use large amounts of water for removing inhibitors and neutralization. In order to reduce water usage, separate batches of corncobs were hydrolyzed in 1M NaOH and 0.05 M H(2)SO(4), respectively, and the hydrolysis products were mixed to achieve a pH of 7. This approach lowered water usage by 10-fold compared with neutralization by distilled and recycling wash water. Mixing of the pretreated biomasses (121°C, 20 min) increased release of reducing sugars during enzymatic hydrolysis with cellulases (38.49 FPU(IU)) produced by Phanerochaete chrysosporium NCIM 1106 by 2- and 15-fold compared with the sugars released from the unmixed NaOH- and H(2)SO(4)-treated corncobs, respectively. Enzymatic hydrolysis (EH, cell free extract) of the mixed material released 395.15 mg/ml of sugars during 48 h, slightly less than what was achieved by microbial hydrolysis (whole cell hydrolysis), 424.50mg after 120 h.
Bio Engineering and Environmental Center (BEEC), Indian Institute of Chemical Technology (CSIR), Tarnaka, Hyderabad 500 607, India. ravichandra.potumarthi@monash.edu
Ravichandra
R
Potumarthi
Rama Raju
RR
Baadhe
Annapurna
A
Jetty
D002241:Carbohydrates / Q000737:chemistry*; D002480:Cellulase / Q000737:chemistry*; D020075:Phanerochaete / Q000201:enzymology*; D035261:Plant Components, Aerial / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D012972:Sodium Hydroxide / Q000737:chemistry*; D013464:Sulfuric Acids / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
D002241:Carbohydrates; D010936:Plant Extracts; D013464:Sulfuric Acids; D014867:Water; D012972:Sodium Hydroxide; D002480:Cellulase; C033158:sulfuric acid