Screening,indetification and enzymatic properties of the high xylanase producing stain

The strain RX-9 producing high xylanase was screened through preliminary screening and shake flask,based on enriched medium with xylan as the sole carbon source. The strain RX-9 had more than 99% homology to Enterobacter,and was ascribed to Enterobacter sp. named as Enterbacter RX-9 by the colony morphology,physiological and biochemical analysis of experiment and genetic analysis of 16s rRNA sequence. The enzymatic properties of xylanase produced by the strain RX-9 was studied,and found that the enzyme activity was still 2310.03 U/mL kept at 100 ℃ for 30 min,and The xylanase activity was above 3200 U/mL when pH was 7.5~9.5. The results showed that the xylanase had good thermal stability and pH stability.