Sterile flasks containing
substrate were then inoculated with 5% spore suspension and
incubated at 30 C. One flask was removed after every 24 h for six
days and 100 mL of 0.05 M citrate buffer (pH 5.3) and Tween 80
(0.1%) were added to it and it was agitated at 180 rpm for 1 h in an
orbital shaker. The contents of the flasks were filtered through
Whatman No. 1 filter paper and the filtrate was centrifuged at
10,000 rpm and 4 C for 10 min and supernatant was collected and
tested for crude endo-b-1,4-xylanase activity.