High purity dyed, soluble Azo-Wheat Arabinoxylan for the measurement of enzyme activity, for research, biochemical enzyme assays and in vitro diagnostic analysis. Prepared by dyeing wheat flour arabinoxylan with Remazol Brilliant Blue R dye. Substrate for the assay of endo-1,4-β-D-xylanase. Please note the video above shows the protocol for assay of endo-cellulase using Azo-CM cellulose. The procedure for the assay of endo-1,4-β-xylanase using Azo-Wheat Arabinoxylan (Powder) is equivalent to this.