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trouble in bioreactor because it caused a lot of foams . Defatted soy bean bascd media which caused less foams, was considered morę appropriate. Table I. sliows celi and spore count for 5 differcnt media. Comparing media II with media I or V, one can see tliat using molasses as additional carbon source, even in smali amount gave significantly better result than using defatted soy bean meal as carbon source alone. Although defatted soy bean meal alone already contained quite high amount of nitrogen, addition of another nitrogen source, such as ammonia or (NH₄)_:S0₄ was beneficial. On the other hand, increasing just only soy bean meal content alone gave poorer result. It is obvious that many factors were involved in celi growth and spore formation, such as amount, type and ratio of carbon and nitrogen and also sonie special nutrients. Media II ,which contain 20 g/L soy bean meal, 3 g/L molasses and 0.5 g/L K:IIP0₄, gave the spore concentration of

feeding of molasses can possibly impecie spore formation due lo the fact that sporulation was initiated by limitation of nutrient.

Fig 2 Celi concentration. spore concentration and reducing sugar in 75 L fermenter cultivation in fed-batcli modę

Fig 2 show a result in 75 t.-fermenter using fed-batch modę. It can be seen that celi concentration plateau was shifted up a bit after

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