Cellulases Specific Activities Study of Enzymes secreted by Fusarium sp. and Phlebia sp. in Aerobic and Anaerobic Conditions

Abstract

Cellulose is the most abundant organic compound on Earth but we can't use it plenty as raw material due to its molecular arrangement and composition. Cellulases are powerful enzymes secreted by some organisms that can be used to degrade cellulose into simple organic molecules like glucose or cellobiose. Although traditional filamentous fungi are known to be excellent cellulose degraders in aerobic conditions, there is little known about cellulose degradation by fungi in anaerobic condition. In this study two facultative anaerobic filamentous fungi isolated and identified using ITS were used to compare cellulase specific activities in aerobic and anaerobic conditions. One Fusarium sp. and Phlebia sp. were grown individually in Potato Dextrose agar for 7 days. Suspensions of spores were prepared for each organism and use it as inoculums. Liquid media culture was prepared and enriched with Carboxylmethylcellulose, Wheat Brand Flour and Whatman no.1 filer paper and inoculated with 1mL of 106 suspension spores of each fungi individually. Cellulase specific activities were determined using Dinitrosalicylic acid method at ph 4, 5, 6, and 7 at 30°C, 40°C, 50°C and 60°C after one month of incubation. Fusarium sp. showed a maximum of cellulase activity at 40°C and pH 5 for both aerobic and anaerobic conditions with values of 0.436 and 0.403 respectively. On the other hand Phlebia sp. showed better results in anaerobic condition with a value of 0.715 at 60°C and pH 6 against a value of 0.632 in aerobic condition at 60°C and ph 5. These results confirm different trending in cellulase specific activities in aerobic and anaerobic conditions and could suggest the presence of different enzymes secreted depending of oxygen concentrations.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.