Effect of the nitrogen source on the biosynthesis, composition, and structure of the exopolysaccharides of Aureobasidium pullulans (de Bary) Arnaud

The effect of the nitrogen source and the CM ratio of the growth medium an the biosynthesis, composition, and structure of the exopolysaccharides (EPS s) of Aureobasidium pullulans (de Bary) Arnaud var. aubasidani Yurlova var, nov, and A. pullulans var. pullulans was studied. A. pullulans var. pullul ans and A. pullulans var, aubasidani strains synthesized the maximum amount s of EPSs in the presence of, respectively, a reduced nitrogen source ((NH4 )(2)SO4) and an oxidized nitrogen source (NaNO3) in the medium. The data pr esented confirm the validity of using the chemical composition and structur e of the major cetavlon-precipitated fraction of A. pullulans EPSs for the characterization of intraspecies taxa.