Enhancement of Cephalosporin C production by cultivation of Cephalosporiumacremonium M25 using a mixture of inocula

Aims: To enhance the productivity of Cephalosporin C (CPC) by cultivation o f Cephalosporium acremonium M25 using a mixture of inocula. Methods and Results: Inoculum age was classified into three stages (early, intermediate and late) by image analysis. A mixture of inocula, according t o the inoculum ages, was used for efficient production of CPC in the main c ulture. The most effective mixing ratio of inocula for CPC production in sh ake flasks was a 3 : 7 volume ratio of early- and late-stage inocula. This was also the case in a 1.5 1 stirred-tank reactor. CPC productivity was enh anced by about 32% and 34% when using an inoculum mixture in the shake flas k and 1 5 1 stirred-tank reactor, respectively. Conclusions: The morphological characteristics of C. acremonium M25 in the seed culture were quite different according to inoculum age. The compromise of different ages of inoculum showed better production of CPC. Significance and Impact of the Study: The productivity of CPC was enhanced considerably when using mixed inocula. The results of this study can be app lied to fungal cultures for efficient production of various metabolites.