This study evaluates the influence of growth parameters such as pH, temperature, Carboxy Methyl Cellulose (CMC) concentration and agitation on cellulase production from three bacterial strains, viz., Achromobacter xyl...This study evaluates the influence of growth parameters such as pH, temperature, Carboxy Methyl Cellulose (CMC) concentration and agitation on cellulase production from three bacterial strains, viz., Achromobacter xylosoxidans BSS4, Bacillus sp. BSS3 and Pseudomonas sp. BSS2 isolated from the wood-yards on Kallai river bank in Kerala. Production of cellulase by these isolates was detected using basal salt medium (BSM) with 0.5% CMC as supplement, and CMCase activity was confirmed by iodine test. Dinitrosalicylic acid method was employed for assaying the cellulase production by measuring the amount of glucose liberated in μmol/mL/min. Maximum enzyme production from Pseudomonas sp. BSS2 was at pH 8, 37℃ with 1% CMC and 150 rpm, and cellulase production increased from initial 49.84 U/mL to 91.28 U/mL after optimization. The highest enzyme activity from Bacillus sp. BSS3 was at pH 9, 37℃ with 1% CMC, 150 rpm, and cellulase production increased from initial 26.05 U/mL to 104.68 U/mL after optimization. The maximum enzyme production from A. xylosoxidans BSS4 was at pH 7, 40℃ with 0.5% CMC and 150 rpm, and cellulase production increased from initial 55.28 U/mL to 68.37 U/mL after optimization. Thus among the three isolates, Bacillus sp. BSS3 showed maximum enzyme yield which can be explored for further scale up studies with an industrial perspective.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This study evaluates the influence of growth parameters such as pH, temperature, Carboxy Methyl Cellulose (CMC) concentration and agitation on cellulase production from three bacterial strains, viz., Achromobacter xylosoxidans BSS4, Bacillus sp. BSS3 and Pseudomonas sp. BSS2 isolated from the wood-yards on Kallai river bank in Kerala. Production of cellulase by these isolates was detected using basal salt medium (BSM) with 0.5% CMC as supplement, and CMCase activity was confirmed by iodine test. Dinitrosalicylic acid method was employed for assaying the cellulase production by measuring the amount of glucose liberated in μmol/mL/min. Maximum enzyme production from Pseudomonas sp. BSS2 was at pH 8, 37℃ with 1% CMC and 150 rpm, and cellulase production increased from initial 49.84 U/mL to 91.28 U/mL after optimization. The highest enzyme activity from Bacillus sp. BSS3 was at pH 9, 37℃ with 1% CMC, 150 rpm, and cellulase production increased from initial 26.05 U/mL to 104.68 U/mL after optimization. The maximum enzyme production from A. xylosoxidans BSS4 was at pH 7, 40℃ with 0.5% CMC and 150 rpm, and cellulase production increased from initial 55.28 U/mL to 68.37 U/mL after optimization. Thus among the three isolates, Bacillus sp. BSS3 showed maximum enzyme yield which can be explored for further scale up studies with an industrial perspective.
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.
