Cellulase manufacturer insulation of thermophilic fungues and production of enzyme by solid culture fermentation

Cellulose biomass is a potential renewable resource for the production of monomeric sugars by hydrolysis with cellulolytic enzymes. Cellulase enzyme, which is composed of endoglucanase, exoglucanase and β-glucosidase enzyme mixtures, breaks down cellulose to glucose with the synergistic effects of these enzymes. These enzymes can be produced by a wide variety of microorganisms, especially fungi. In this study, thermophilic fungus Aspergillus fumigatus, which hydrolyzes carboxymethyl cellulose (CMC) at the highest rate, was isolated from the forest soils in Tokat province and the samples enriched from the compost production facility in our campus. As a result of the 18s rRNA sequencing analysis, the production parameters of the thermophilic fungus named A. fumigatus BHC05 were optimized by the solid culture fermentation of the extracellular cellulase enzyme. After determining the carbon source, nitrogen source, moistening ratio, surface surfactant effect and production time, the pH of the enzyme produced (3.0-4.0 - 5.0 - 6.0 - 7.0 - 8.0 - 9.0 - 10.0), temperature (30°C, 40°C, 50°) C, 60°C, 70°C, 80°C, 90°C) and thermal stability (24 h – 96 h – 336 h) were investigated. Cellulase activity was quantitatively measured spectrophotometrically by DNS method using CMC substrate. Optimum activity of the enzyme in SSF medium with thermophilic fungus 0.1% (v/v) tritonX100 surface surfactant, 1:1 (w/w) moistening liquid, orange carbon and NaNO3 nitrogen source and substrate (1.0% w/v) CMC) at pH 5.0, 50 ºC and 60 min incubation, the enzyme activity measured by DNS method showed 2870 U/mL. The enzymatic properties of cellulase produced in thermophilic fungus SSF medium were also evaluated. Accordingly, the optimum activity of the enzyme was shown at pH 6.0 and temperature 70 °C. It preserved 80% of its activity for 15 days at 30°C – 40°C – 50°C – 60°C. In this study, it has been shown that the cellulase produced by the thermophilic fungus has a good potential to be used in the industrial field due to its activity efficiency. Keywords: Cellulase, Thermophilic Fungus Isolation, Carboxymethyl and Cellulase Activity