Abstract

Chaetomium thermophile produces substantial extra-cellular cellulase on several cellulosic substrates (wheat straw, wheat bran and corn straw etc.) including simple sugars. 2% (w/v) wheat straw, wheat bran and corn straw were used as carbon source and urea was used as a nitrogen source. Experiment wasconducted in a 20-l stirred tank reactor under the following conditions: pH 5.0, stirring speed 300 rpm, temperature 45^oC and aeration 50% (DO). The samples were withdrawn after every 12 h regularly and enzyme activity was assayed. Endo-b-1,4-glucanase activities on wheat straw, wheat bran and corn straw were 2.51, 1.62 and 5.10 U/ml, respectively and extra-cellular protein contents were 1.48, 1.17 and 2.88 mg/ml, respectively. Specific activity of enzyme after ammonium sulphate precipitation and Fast Protein Liquid Chromatography (FPLC) was 2.1 and 3.3 U/mg of protein, respectively. SDS-PAGE showed only a single band at 53 kDa. The optimum temperature and pH of the CMCase were 60^oC and from 6.0 - 7.5, respectively.

Key words: Chaetomium thermophile, cellulase, fermentation, extra-cellular enzymes, agro-wastes.