A NOVEL RAPID COUPLED ENZYME ASSAY FOR THE ESTIMATION OF PULLULAN

A new method for the assay of the polysaccharide pullulan is described in which it is enzymically hydrolysed by pullulanase and glucoamylase . The reaction products are determined colorimetrically by a glucose o xidase method, the absorbance at 515 nm being measured. The rate of co lour production depends on the pullulan concentration. The Lineweaver- Burk, Hanes-Woolf and Eadie-Hofstee plots show good linearity with res pect to the concentration of pullulan. The assay is sensitive down to 100 mg of pullulan/litre. This coupled-enzyme assay method has been ap plied to ethanol-precipitated substances containing pullulan derived f rom fermentations of various agroindustrial wastes. The assay is simpl e, rapid and suitable for both industrial applications and in teaching biotechnology and biochemist students.