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The Gellan-type polysaccharide produced by Pseudomonas elodea( ATCC 31461) is one of the new heteropolysaccharides, having useful properties as gelling, suspending, stabilizing, emulsifying and binding agents in aqueous systems. Medium compositions for growth stage and production stage are improved. The problems of low cell concentration and poor productivity in highly viscous fermentation were attributed to inadequate mixing accompanied by insufficient oxygen transfer. During continuous culture, cell growth and polysaccharide production were greatly affected by the apparent viscosity, and they showed oscillation behavio;i.e. as the product concentration increases, cell concentration decreases. With improved culture conditions, the productivity of continuous culture increased up to 0.6g/P /hr (6-fold that of batch culture) at dilution rate, D=0.14hr^(-1)
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