초록
<P>Three sequential fermentative batches were carried out with cell recycle in four simultaneously operating bioreactors maintained at pH 6.5, 30°C, and 100 rpm. <I>P. acidipropionici</I> ATCC 4875 was able to produce propionic and succinic acid from sorbitol. The concentration of propionic acid decreased slightly from 39.5 ± 5.2 g L<SUP>−1</SUP> to 34.4 ± 1.9 g L<SUP>−1</SUP>, and that of succinic acid increased significantly from 6.1 ± 2.1 g L<SUP>−1</SUP> to 14.8 ± 0.9 g L<SUP>−1</SUP> through the sequential batches. In addition, a small amount of acetic acid was produced that decreased from 3.3 ± 0.4 g L<SUP>−1</SUP> to 2.0 ± 0.3 g L<SUP>−1</SUP> through the batches. The major yield for propionic acid was 0.613 g g<SUP>−1</SUP> in the first batch and succinic acid it was 0.212 g g<SUP>−1</SUP> in the third batch. The minor yield of acetic acid was 0.029 g g<SUP>−1</SUP>, in the second and third batches.</P>