Abstract
Six strains of homofermenters produced L-arabinose isomerase in only the L-arabinose-medium, and with these bacterial cells which were obtained from the medium containing glucose, fructose or mannose, any activity of this enzyme was not pointed out. Moreover the L-arabinose isomerase of six strains of heterofermenters and of Pediococcus lindneri, and also D-xylose isomerase of six strains of heterofermenters and of L. xylosus are produced even in glucose, fructose, mannose, galactose or pentose-media. The amounts of D-xylose isomerase of L. fermentum varied according to the kind of carbon source of the growing culture. This xylose isomerase is produced abundantly in the cells grown on mannose, L-arabinose and D-xylose-media. Glucose, galactose, maltose, sucrose, and gluconate do not show any stimulating effect on the production of xylose isomerase.
