Sciences & Technologie
Volume 0, Numéro 12, Pages 65-70
1999-12-31

High Level Production Of Thermostable -xylanase, Cmc-ase And -glucosidase By An Aspergillus Fumigatus (fresenius) Albino Mutant Strain

Auteurs : Saradouni N . Penninckx M.j . Salhi O .

Résumé

A local isolate of Aspergillus fumigatus (Fresenius) albino mutant obtained from rotten wood shavings, grew at 45°C on a solid medium containing cellulose as carbon source. This fungus can utilize a variety of lignocellulosic substrates, such as Kraft paper pulp, straw, microcrystalline cellulose and filter paper. The highest endoglucanase (CMC-ase), -xylanase and -glucosidase activities were obtained in shaken flasks at 45°C, with mainly oat straw as sole carbon source. CMC-ase and -xylanase activities showed the highest values (3.50 U/ml and 33 U/mI) at pH 4.0 and 5.0 respectively, and 70°C. -glucosidase activity was maximal at 65°C (43 U/ml ), CMC-ase and -xylanase enzymes were active in a large pH spectrum (3.0 to 8.0) and showed high thermostability at 60°C and above, especially for CMC-ase.

Mots clés

ignocellulosic materials, Carboxymethylcellulose, xylan, straw, cellulases, -xylanases, thermophilic fungus, growth rate, submerged culture. Résumé