Reducing process cost of the bioconversion of lignocellulosic is a challenge. In China, abundant acidic wastewater from monosodium glutamate production is difficult to treat, leading to serious water pollution. In this study, acidic liquid (ALC) and solid residue components (SC) obtained from the wastewater were used in pretreatment and cellulase production, respectively, to evaluate their potential in bioconversion of corn stover. Optimum pretreatment conditions (170 degrees C, 60 min, 0.75% ALC) were identified by a central composite design method. There were little difference in the chemical components and digestibility (above 84%) of between ALC and H(2)SO(4)-treated corn stover, and amounts of HMF and furfural in liquor after pretreatment with ALC and H(2)SO(4) under optimum conditions. SC can be substituted for (NH(4))(2)SO(4) in liquor fermentation to produce cellulase with comparable filter paper (about 10.7 U/ml) and beta-glucosidase (about 2.7 U/ml) activities. (C) 2010 Elsevier Ltd. All rights reserved.