PRODUCTION OF PROTEASE ENZ17ME BY SOME THERMOPHILIC AND THERMOTOLERANT FUNGI AND THEIR COMPATIBILITY WITH COMMERCIAL DETERGENTS. .

Abstract

Seven locally isolated thermophilic and thermotolerant fungi namely; Thermoascus aurantiacus, Emericella nidulans, Malbranchea sulfurea, Myceliophthora thermophila, Talaromyces thermophila, Aspergillus terreus and Aspergillus niger were screened for protease production. Myceliophthora thermophila, Malbranchea suljurea and Aspergillus terreus were found to be the most potent fungi. The study of the effect of temperature of incubation on mycelial growth revealed that M. thermophila and M suljurea are true thermophiles and A. terreus is a thermotolerant mesophile. Optimization of alkaline protease of the three fungi revealed that the maximal production of protease was attained after 6 days of incubation. The optimum pH was 6.0 forM thermophila and pH 7.0 for both M sulfurea and A. terreus, The optimum temperature was 45°C for both M thermophila and M suljurea and 40°C for A. terreus. The best protein• substrate was bovine serum albumin (0.9%, WN) forM thermophila, peptone (0.6%, WN) for M sulfurea and casein (0.6%, WN) for A. terreus. The best carbon source was mannitol (5.5%, WN) in M thermophila, sucrose (3.5 and 3.0%, W/V) inM sulfurea and A. terreus, respectively. Using of whey, cane molass, beet molass, corn meal, gluten (23.% & 11.36% N) and ragee elkon increase the production of protease by the three fungi.