Abstract:
Soil, sisal stem and leaf samples in sisal plantations, and residues from rope manufacturings were collected for isolation and screening of fungi that produce enzyme cellulases. Among the 99 isolates obtained, 52 isolates showed cellulolytic activities. A fungal isolate with the highest filter paper activity (FPA) of 0.274 u/ml at 37°c was identified as Acrophialophora sp. The cellulase production from the isolated Acrophialophora sp., grown in shake-flask culture, produced enzyme cellulase optimally at 40 °c with an initial pH of 5.0, having microcrystalline cellulose (MCC) at 3% concentration as a carbon source and NH4NO3 at 0.4% concentration as a nitrogen source. The addition of casein at 0.100% concentration increased the FPA and carboxymethyl cellulase (CMCase) by 1.26 and 1.66-fold consequently. When producing the enzyme cellulase in a 5 liters fermentor, the uncontrolled pH condition gave higher FPA and CMCase than the controlled pH condition at 5.00 around 1.03 and 1.10-fold consequently. When Acrophialophora sp. and S. cerevisiae were used together in a mixed-culture fermentation process for ethanol production, the ethanol yield was 0.733 g/100 ml or 0.244 g ethanol/g substrate (g/g) at 40 °c using sisal fibers as a substrate. When T. reesei and S. cerevisiae were used together, the ethanol yield was at 1.530 g/100 ml or 0.510 g/g.