Simplified Microassay for Pullulan Synthesis

A simple radiometric microassay for extracellular polysaccharide elaboration by yeast-like cells of Aureobasidium pullulans was developed, based upon a procedure originally described by Catley (FEBS Lett. 20:174-176, 1972). Incorporation of ¹⁴C]glucose into pullulan was linear with respect to time and cell dose. The pH and temperature optima for elaboration were 5.3 and 30°C, respectively. Polysaccharide elaboration declined linearly with culture age.