Screening and Identification of a Wild Cellulose-degrading Strain with High Efficiency and Determination of Its Enzyme Activity

In order to isolate cellulase-producing bacteria from the overrotten soil and further study the cellulose degradation ability of the strain, a wild cellulose-degrading strain ZG2-3 was screened by using the carboxymethyl cellulose (CMC) - congo red staining method. Then, the 16 S rRNA molecular identification was used to identify the species, and four commercial cellulose-degrading bacteria strains were screened from the promoting-decomposing agent. Last, the enzyme activity differences between the wild cellulose-degrading bacteria and the commercial cellulose-degrading bacteria were compared. The results showed that one strain of bacteria with high cellulose degradation ability, ZG2-3, was screened by using the carboxymethyl cellulose (CMC) - congo red staining method, which was collected and isolated from the overrotten soil under the osmanthus forest in Zhushan Park, Loudi City. ZG2-3 was identified as Bacillus subtilis. The carboxymethyl cellulase (CMCase) activity and filter paper enzyme (FPA) activity of ZG2-3 were 0.054 IU·mL⁻¹ and 0.02 IU·mL⁻¹, respectively, and the CMCase activity of ZG2-3 was significantly higher than that of the commercial cellulose-degrading bacteria.