Production of L-phenylacetyl carbinol by immobilized yeast cells: I. Batch fermentation.
Immobilization of Saccharomyces cerevisiae ATCC 834 within alginate beads enhances microbiological conversion of benzaldehyde to L-phenylacetyl carbinol (L-PAC), a precursor employed for synthesis of L-ephedrine. Yields of 90% L-PAC on benzaldehyde (initially 0.6% in medium) were obtained with immobilized cells, in contrast to about 10% with free cells which tend to form pellets in the presence of benzaldehyde. The predominant favorable action of immobilization appears to be a reduction in the toxic or inhibitory effects of benzaldehyde. With an initial benzaldehyde concentration of about 0.6% in the medium the optimum cell mass concentration was observed to be about 28 g cell mass (immobilized) per liter of medium.
Mahmoud
W M
WM
Department of Chemical Engineering and Biotechnology Center, University of Connecticut, Storrs, Connecticut 06268, USA.
El-Sayed
A H
AH
Coughlin
R W
RW