Ammonium sulfate growth with

Variation of geometric mean radius (rso) of sulfate particles as a function of relative humidity (crosses). Solid line represents the theoretical growth of an ammonium sulfate particle with r = 0.14 /jm (E. Meszaros, 1970). (By courtesy of Tellus)... 

S. cerevisiae is produced by fed-batch processes in which molasses supplemented with sources of nitrogen and phosphoms, such as ammonia, ammonium sulfate, ammonium phosphate, and phosphoric acid, are fed incrementally to meet nutritional requirements of the yeast during growth. Large (150 to 300 m ) total volume aerated fermentors provided with internal coils for cooling water are employed in these processes (5). Substrates and nutrients ate sterilized in a heat exchanger and then fed to a cleaned—sanitized fermentor to minimize contamination problems. 

In addition there is other evidence pointing to the fact that the same enzyme is involved in reactions with both D-fructose and L-arabinose. First, the relative rates of reaction with D-fructose and L-arabinose, respectively, remain constant after partial inactivation of the enzyme by heat. Second, the enzyme catalyzing both reactions is produced to a marked extent when sucrose is used as substrate for the growth of the organisms, but not when D-glucose or L-arabinose is used sucrose phos-phorylase is an adaptive enzyme. Third, on fractionation of the enzyme preparation with various concentrations of ammonium sulfate, the relative activities of the fractions are the same for both sugars. These observations indicate not only that the same enzyme is involved in both reactions but also that no additional enzyme is required for the formation of D-glucosyl-L-arabinose. 

FIG. 20-73 (a) Maximum extent of noninertial growth (/d)max a function of fractional saturation of the powder feed S t for drum granulation, and (b) maximum extent normalized for differences in Sto- Feed powders ammonium sulfate (O) monoammonium phosphate ( ), diammonium phosphate (A), limestone ( ). [Adetayo etd.. Powder Tech., 82.37 (1995). ] With kind permission from Elsevier Science SA, Lausanne, Switzerland. 

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