| Abstract: | Fermentation studies using batch culture indicated that exopolysaccharide production by Pseudomonas NCIBI1264 in a chemically defined medium increased under conditions of nitrogen limitation and excess carbon substrate at pH values above 6. The polysaccharide was formed from a variety of carbon substrates and its composition was not affected by the nature of the carbohydrate source. Polysacharide formation did not increase in media containing small amounts of phosphate, and, as in secondary metabolite production, it started late in the exponential growth phase continuing maximally after growth had ceased. The efficiency of glucose conversion into exopolysaccharide was low. Colorimetric, viscometric, and total carbon estimation techniques are described for determining exopolysaccharide levels in cell-free culture supernatants. |
