Production of alkaline xylanase by an alkaliphilic Bacillus sp. isolated from an alkaline soda lake

An alkaline xylanase-producing alkaliphilic Bacillus sp. AR-009 was isolated from an alkaline soda lake in Ethiopia. The enzyme was optimally active at pH 9 and was stable over a broad pH range. The optimum temperature for xylanase activity, assayed at pH 9, was 60 degrees-65 degrees C. Measured at pH 8 and 9, the enzyme had good stability at 55 degrees and 60 degrees C. At both pH values, over 80% of its original activity was retained after heating for 2.5 h at 5 degrees C. At 60 degrees C, the enzyme maintained 63% of its original activity after 2.5 h incubation while at pH 9 it retained 54% of its original activity after I h heating. These properties qualify the enzyme to be novel and potentially important for application in some industrial processes.