STUDIES ON CELLULYTIC FUNGI

Abstract

I. This work began by isolating 77 fungal strains from different •localities from

Sharkia Governorate, Egypt. The isolates culture were purified and then

. tested for their cellulolytic activity. Twenty four strains, which showed much enzymatic activities. The two isolates number 30 and 44 were used for further studies due to its high collulolytic activities, and these, isolates identified as Trichoderma viride & Fusarium xysporium. • II. The environmental conditions and nutritional requirements were conducted

for improving cellulase biosynthesis by Trichoderma viride & Fusarium oxysporium as the follows: A- Environmental factors affecting cellulase biosynthesis as hydrogen ions concentration, incubation temperature and incubation time. The results proved that maximum cellulase biosynthesis was attained after 15 days of incubation and in presence of nutrient medium of pH 5.0 at 27°C. B- Nutritional requirement affecting cellulase biosynthesis proved that:

1. Twenty carbon sources were tested for maximal enzyme biosynthesis.

These sources include cellulosic compound, raw callulosic material and

• other carbon sources. Among the cellulosic compound tested, cellulose powder was found to be the most suitable substrate for maximum enzyme biosynthesis at concentration of 10 gm/1. for both tested organisms. 2. Nine nitrogen sources were supplemented for their effect on cellulase biosynthesis. These include organic and inorganic nitrogen sources. Peptone is the best nitrogen source, which more favoured for cellulase biosynthesis at a concentration of 3.5 gm/1. for both tested organisms.