Carboxymethylcellulase production by the anaerobic rumen fungusNeocallimastix sp. GMLF7

Anaerobic fungi have highly active fibrolytic enzymes and these enzymes are attractive for scientific research. We isolated a ruminal fungus of the genus Neocallimastix sp., named GMLF7, which could survive on a variety of cellulosic material such as carboxymethylcellulose (CMC), fibrous cellulose, avicel and wheat straw. Carboxymethylcellulase production was investigated with the above carbon sources and high CMCase activity was obtained with CMC (73.75 U/ml), fibrous cellulose (72.68 U/ml) and avicel (70.03 U/ml). While growth temperature of the microorganism was 39°C, for CMCase activity optimal temperature was 50°C and optimal pH 6.5. Enzyme reached maximum activity in 60–180 min at 50°C. Substrate concentration also affected the enzyme activity which was increased more than 2 fold with 40 mg/ml CMC. Activity was measured in presence of various divalent ions and reagents, and Co 2+ and DTT has a positive effect on the enzyme activity.