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 [C]glucose into pullulan was linear with respect to time and cell dose. The pH and temperature optima for elaboration were 5.3 and 30 degrees C, respectively. Polysaccharide elaboration declined linearly with culture age.