Endophytic fungus Fusarium oxysporum is a rich source of cellulases. In the present study, the highest activity was reported at 28 ° C, pH 5.6 with 2% Carboxymethyl cellulose (CMC) as carbon source. CMC was purif...Endophytic fungus Fusarium oxysporum is a rich source of cellulases. In the present study, the highest activity was reported at 28 ° C, pH 5.6 with 2% Carboxymethyl cellulose (CMC) as carbon source. CMC was purified using Sephadex G and DEAE cellulose chromatography to 15.9 folds and the molecular weight was determined to be 84 kDa by SDS-PAGE analysis and was subsequently characterized. The purified enzyme was stable over the pH range from 4.0 to 8.0 and at temperatures below 50 ° C. The enzyme was highly active on CMC and reduced or no activity on Avicel, cellobiose and it was suggested to be CMCase/endoglucanase. The activity of endoglucanase was enhanced in the presence of MgCl2, CoCl2, FeCl3, CaCl2, FeCl2 and intensive to HgCl2. The purified enzyme showed its optimum activity at pH 5.0 - 6.0 and was quite stable at 50 ° C for 30 min and retained 45% of original activity.展开更多
Five thermophilic strains that can degrade cellulose were isolated from the compost of a waste management in Guangzhou, China. Since one of them degraded cellulose effectively, it was chosen as the study strain. Based...Five thermophilic strains that can degrade cellulose were isolated from the compost of a waste management in Guangzhou, China. Since one of them degraded cellulose effectively, it was chosen as the study strain. Based on its morphology, spores′ susceptibility to heat, cell wall composition and other characteristics, the organism was classified as Thermomonospora fusca. Conditions for production of carboxy methyl cellulase (CMCase) were examined. The optimal temperature and pH value for enzyme production were 50 ℃ and 10.5, respectively. Cellulosic materials and easily metabolisable carbohydrates served as carbon sources for the growth of the strain. Only cotton, avicel,carboxy methyl cellulose (CMC) acted as potent inducers for the production of cellulases by this strain. Despite excellent growth on easily metabolisable carbohydrates, only constitutive levels of cellulases were produced. The optimal carbon and nitrogen sources for CMCase production were cotton and soybean respectively. The high thermostability, wide pH stability, and cheap nitrogen source show well potential use for composting treatment and commercial detergents.展开更多
文摘Endophytic fungus Fusarium oxysporum is a rich source of cellulases. In the present study, the highest activity was reported at 28 ° C, pH 5.6 with 2% Carboxymethyl cellulose (CMC) as carbon source. CMC was purified using Sephadex G and DEAE cellulose chromatography to 15.9 folds and the molecular weight was determined to be 84 kDa by SDS-PAGE analysis and was subsequently characterized. The purified enzyme was stable over the pH range from 4.0 to 8.0 and at temperatures below 50 ° C. The enzyme was highly active on CMC and reduced or no activity on Avicel, cellobiose and it was suggested to be CMCase/endoglucanase. The activity of endoglucanase was enhanced in the presence of MgCl2, CoCl2, FeCl3, CaCl2, FeCl2 and intensive to HgCl2. The purified enzyme showed its optimum activity at pH 5.0 - 6.0 and was quite stable at 50 ° C for 30 min and retained 45% of original activity.
文摘Five thermophilic strains that can degrade cellulose were isolated from the compost of a waste management in Guangzhou, China. Since one of them degraded cellulose effectively, it was chosen as the study strain. Based on its morphology, spores′ susceptibility to heat, cell wall composition and other characteristics, the organism was classified as Thermomonospora fusca. Conditions for production of carboxy methyl cellulase (CMCase) were examined. The optimal temperature and pH value for enzyme production were 50 ℃ and 10.5, respectively. Cellulosic materials and easily metabolisable carbohydrates served as carbon sources for the growth of the strain. Only cotton, avicel,carboxy methyl cellulose (CMC) acted as potent inducers for the production of cellulases by this strain. Despite excellent growth on easily metabolisable carbohydrates, only constitutive levels of cellulases were produced. The optimal carbon and nitrogen sources for CMCase production were cotton and soybean respectively. The high thermostability, wide pH stability, and cheap nitrogen source show well potential use for composting treatment and commercial detergents.
