**2.12 pH and temperature profiles and thermostability of xylanases**

Xylanase activity was examined in pH range of 3.0 to 11.0. For pH from 3.0 to 4.0, 100 mM sodium citrate buffer was used. For pH from 4.0 to 6.0, 100 mM sodium acetate buffer was used. For pH from 6.0 to 8.0, 100 mM sodium phosphate buffer was used. For pH from 8.0 to 9.0, 100 mM Tris-HCl buffer was used. For pH from 9.0 to 11.0, 100 mM glycine-NaOH buffer was used. To investigate the effect of temperature, the xylanase activity was measured at 20-70°C at pH 6.5. Xylanase thermostability was measured at 50, 55 and 60°C.
