Abstract: Based on the primary studies on the enzymatic hydrolysis conditions of arabinoxylan in wheat bran, the enzymatic degradation conditions of arabinoxylan were optimized by quadratic regression orthogonal rotary tests. The quadratic orthogo-nal regression model is of arabinoxylan yield (Y) to four factors of temperature (X1), time (X2), the concentration of enzyme (X3) and pH value (X4) and established as Y=12.84921-1.36983X1+0.69076X2+0.75443X3-1.46276X12-0.93773X42. It was concluded from the model that when temperature, time, enzyme concentration and pH value are 60 ℃, 3 h, 0.75% and 5 respectively, the yield (Y) is the maximal (15.28%) and consistent with the confirmatory experiment result.

Key words: arabinoxylan, pentosanase, enzymatic hydrolysis conditions, orthogonal rotation combination design, optimization