Using CMC plat screening and Congo red dying methods

a strain of cellulase-producing bacterium named CXB001 was isolated from the soil around rotten root of

Hibiscus mutabili

on the campus of Hunan University of Science and Technology. Physical and chemical test and molecular phylogenetic analysis based on 16S rDNA sequences showed that the strain was

Bacillus velezensis

. Biological charateristics revealed that the optimal growth temperature is 37 ℃

and the growth temperature ranges from 10 ℃ to 50 ℃

while the growth pH ranges from 5.0 to 11.0. The culture conditions at pH 6.0~9.0，34~40 ℃ and 1.5%~3.5% NaCl are the most suitable for enzyme production. The optimal temperature for CXB001 to produce cellulase is 50 ℃

while the optimal reaction pH is 5.0

and the strain has nice enzyme stability in 20 ℃

pH 5.0~7.0. Further experiments revealed that Co

2+

could stimulate the cellulase

while Mg

2+

and Fe

2+

inhibit the enzyme reaction.