Résumé:
The microscopic study of the moulds isolated from Sebkhas of Biskra area allowed, to
identify 7 different kinds from 10 potentially cellulolytic strains: Aspergillus, Penicillium,
Geotrichum, Altarnaria, Cladosporium, Altarnaria and Trichoderma.
The fermentation of the 10 strains selected and cultivated on a medium containing date
scrap (under product of pheonicical industry) as a substrate of fermentation, allowed to select
hypercellulolytic strains with a cellulasic activity of 775 U. The strain (R3), isolated from the
ground soil of palm plantations of Biskra corresponds to the Trichoderma kind. This train is
retained for the kinetic study of the biomass, the cellulasic activity, sugar, proteins like that of
the pH. This study reveals that the synthesis of the enzyme reaches its maximum after 60
hours of fermentation during the stationary phase of the growth.
A partial purification with ammonia sulphate 40 % of saturetion reduced the content of
proteins of 78.4 % and increased the specific activity to 94.35 % which reached the degree of
purification to 17.70. The enzyme was found very thermostable with a half-life of 170 , 140,
120 and 50 munites at 60, 70, 80 and 90°C respectively. The corresponding temperature for
the maximum cellulolytic activity was 55°C whereas the optimim pH was 4.8.
