Isolation,identification and enzymatic properties of halophilic cellulase-producing fungi from Chaka Salt Lake
To obtain halophilic cellulase-producing fungi from the Chaka Salt Lake,Qinghai Province,PDA medium containing 5%NaCl was used as an isolation medium to obtain halophilic fungi strains.After initial screening with sodium carboxymethyl cellulose(CMC)as the only carbon source,the enzyme properties of cellulase produced by high-activity strains were studied by Congo red plate.The results showed that 24 strains of cellulose-degrading bacteria were obtained from the samples of Chaka Salt Lake,which belonged to 10 different genera.A highly active strain was obtained by primary screening and rescreening,named DaliF28,and identified as Cladosporium sp.by ITS gene.After 32 hours of liquid fermentation and culture of Cladosporium sp.DaliF28,the cellulase activity in the supernatant reached a maximum of 32.87 U/mL.The optimum temperature,pH,and salt concentration of cellulases produced by Cladosporium sp.DaliF28 were 50℃,6.6,and 2.5 mol/L NaCl,respectively.It remained above 60%relative activity after incubated at the optimum pH and salt concentration at 60℃for 1 h,and still exhibited more than 60%relative activity at the concentration of 0-4 mol/L NaCl.The isolated strains indicated that there are abundant halophilic cellulase-producing fungi in Chaka Salt Lake.
Qinghai Chaka Salt Lakehalophilic fungiisolation and screeningcellulaseenzymatic properties
万方数据
维普
