Among 20 bacterial isolates isolated from the soil of El-hawia, El-hada, El-kaym and Karwa in Taif governorate in Saudi Arabia,two isolates had high efficacy in producing cellulase enzyme. They belonged to genus Bacillus (Bacillus 8 and 17). Some factors such as carbon source and wheat bran as a raw material, nitrogen source, pH and. incubation temperature were investigated. Results indicated that CMC and cellulose were the most effective as they enhanced cellulases production .Sodium nitrate and ammonium chloride were the best nitrogen sources for cellulases production. Initial pH 7.0 was found to be optimal for growth and cellulase production. Incubation temperatures at 25 - 40°C achieved high cellulases production by the two isolates.

Among 17 fungal isolates isolated from soil of El-hawia, El-hada, El-kaym and Karwa in Taif governorate in Saudi Arabia, two isolates showed high efficacy in producing cellulases enzymes. They were identified to be Altemaria altemata and Aspergillus wentii. Some factors such as carbon and wheat bran as a raw material, nitrogen, pH and incubation temperature were investigated. Results indicated that glucose and cellulose were the most effective as a carbon source while, urea was the best nitrogen source for cellulases production. Initial pH 5.0 and incubation temperatures at 25 or 35°C achieved high cellulases production.