title: Production and characterization of cellulolytic enzymes from the thermoacidophilic fungal Aspergillus terreus M11 under solid-state cultivation of corn stover.
abstract: The production of extracellular cellulases by a newly isolated thermoacidophilic fungus, Aspergillus terreus M11, on the lignocellulosic materials was studied in solid-state fermentation (SSF). The results showed that the high-level cellulase activity was produced at 45 degrees C pH 3 and moisture 80% with corn stover and 0.8% yeast extract as carbon and nitrogen sources. 581 U endoglucanase activity, 243 U filter paper activity and 128 U beta-glucosidase activity per gram of carbon source were obtained in the optimal condition. Endoglucanase and beta-glucosidase exhibited their maximum activity at pH 2 and pH 3, respectively, and both of them showed remarkable stability in the range of pH 2-5. The activities of endoglucanase and beta-glucosidase were up to the maximum at 70 degrees C and maintained about 65% and 53% of their original activities after incubation at 70 degrees C for 6h. The enzyme preparations from this strain were used to hydrolyze Avicel. Higher hydrolysis yields of Avicel were up to 63% on 5% Avicel (w/v) for 72 h with 20 U FPase/g substrate.
authors.affiliation: Department of Bioengineering, Zhengzhou University, 100 Kexue Road, Zhengzhou 450001, PR China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Gao
authors.forename: Haibo
authors.initials: H
authors.lastname: Weng
authors.forename: Daheng
authors.initials: D
authors.lastname: Zhu
authors.forename: Mingxue
authors.initials: M
authors.lastname: Yuan
authors.forename: Fangxia
authors.initials: F
authors.lastname: Guan
authors.forename: Yu
authors.initials: Y
authors.lastname: Xi
mesh_terms: D001230:Aspergillus / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D002244:Carbon / Q000378:metabolism; D044602:Cellulases / Q000096:biosynthesis* / Q000737:chemistry; D002482:Cellulose / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases / Q000378:metabolism; D004795:Enzyme Stability; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D009584:Nitrogen / Q000378:metabolism; D010802:Phylogeny; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013696:Temperature; D013997:Time Factors; D003313:Zea mays / Q000378:metabolism*; D001617:beta-Glucosidase / Q000096:biosynthesis
chemical_list: D002244:Carbon; D002482:Cellulose; D044602:Cellulases; D001617:beta-Glucosidase; D043364:Endo-1,4-beta Xylanases; D009584:Nitrogen