[Screening and Enzyme Production Characteristics of Thermophilic Cellulase-producing Strains]

A total of 6 thermophilic cellulase-producing strainswere isolated from organic garden waste mixed chicken composting at thermophilic period. These isolates were identified as Streptomyces thermoviolaceus, S. thermodiastaticus, S. thermocarboxydus, S. albidoflavus, S. thermovulgaris and Brevibacillus borstelensis through 16S rRNA gene sequence alignment and phylogenetic tree analysis. The cellulose-degrading microbial community has been investigated in few researches so far both at home and abroad. In this study, the mixed strains M-1 was made up of the 6 cellulose-decomposing microorganisms. The CMCase activity of the mixed strains M- 1 was stronger than any of the 6 single strains. Production of CMCase from mixed strains M-1 was studied by optimizing different physico-chemical parameters. The Maximum CMCase production (135.9 U · mL⁻¹) of strains M-1 was achieved at 45 °C in a liquid medium (pH 4) inoculated with 1% (volume fraction), containing a mixture of wheat bran and starch, corn flour and KNO₃. After optimization of separation conditions, CMCase production capacity was improved by 1.8 times.