|Pan, Zhongli - John|
Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings
Publication Acceptance Date: 6/25/2007
Publication Date: 6/25/2007
Citation: Zheng, Y., Pan, Z., Zhang, R., Labavitch, J., Wang, D., Jenkins, B.M. 2007. Adsorption Characteristics of Cellulase and Beta-Glucosidase to Lignin, Cellulose and Pretreated Creeping Wild Rye Grass. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE). Paper No. 077074. St. Joseph, Mich.:1-13. Interpretive Summary: This study investigated the adsorption characteristics of enzymatic hydrolysis of lignocellulosic biomass. It provided important information for optimizing the enzymatic hydrolysis of L. triticoides and other lignocellulosic biomass.
Technical Abstract: Enzyme adsorptions, including productive and non-productive adsorptions, are the important factors affecting the rate and degree of enzymatic hydrolysis of lignocellulosic biomass. They are directly related to the required amount of enzyme needed for achieving desired sugar yields. The non-productive adsorption of cellulase and beta-glucosidase to lignin in lignocellulosic biomass reduces enzyme availability and glucose yield. The better understanding of enzyme adsorption characteristics could reduce enzyme consumption resulting in lowered production costs for bioethanol and biochemicals through hydrolysis of lignocellulosic biomass. The objective of this study was to investigate the adsorption characteristics of cellulase and beta-glucosidase to lignin, cellulose (Avicel PH101) and dilute acid-pretreated Creeping Wild Ryegrass (CWR) (Leymus triticoides). Cellulase and beta-glucosidase were Cellucalst 1.5L from Trichoderma reesei and Novezyme 188 from Aspergillus niger, respectively. CWR was pretreated by dilute sulfuric acid and lignin was obtained as the residue of enzymatic hydrolysis of pretreated CWR. The enzymes in the adsorption experiments were quantified by protein measurement using Bio-Rad protein reagent. Results showed that beta-glucosidase had much a higher affinity to lignin than cellulase did. Cellulase had much a stronger adsorption capability to cellulose than beta-glucosidase. Langmuir isotherms were adapted to describe the adsorption behavior of cellulase and beta-glucosidase, respectively. This study provided important information for optimizing the enzymatic hydrolysis of CWR and other lignocellulosic biomass.