Fed-batch cultivation of Acetobacter suboxydans for the microbial oxidation of D-sorbitol to L-sorbose

Abstract

Microbial oxidation of D-

Synthesis of l-Hexoses

“…Other l -ketoses have been synthesized in this manner such as l -tagatose ( 31 ) by microbial oxidation of galactitol ( 506 ), , l -fructose ( 475 ) from l -mannitol ( 176 ), l -psicose ( 479 ) from allitol ( 507 ), and obviously l -sorbose ( 452 ) by oxidation of sorbitol ( 508 ) (Scheme ) . There is considerable literature on the latter process as it is the first step of a two-step biotechnological process for preparation of vitamin C from 508 . − Many smart developments such as immobilized organisms, − thermoresistant strains, fed-batch methods, − continuous fermentation, computer-coupled substrate feeding, and using oxygen vectors have been reported. Yields are frequently over 90%, but byproducts such as d -fructose and d -mannitol can be formed, and rates can be limited …”

Study of the inhibitory effect of the product dihydroxyacetone on Gluconobacter oxydans in a semi-continuous two-stage repeated-fed-batch process

“…Furthermore, it was shown that the effect of growth inhibition by DHA was stronger compared to other products such as L-sorbose. According to Giridhar and Srivastava [13], the cells were able to grow even at a L-sorbose concentration of 200 kg m À3 . However, a literature survey revealed that the state of knowledge on the regeneration capability of G. oxydans in dependence of the DHA concentration is low.…”

Metabolic Engineering of Microorganisms for Vitamin C Production

“…Dissolved oxygen was also an important factor in the fermentation process of vitamin C. Giridhar and Srivastava ( 2000 ) found that in the batch and fed-batch fermentation processes of D-sorbitol to L-sorbose, adding 4% of the oxygen vector (N-hexadecane) could shorten the period for 2 and 5 h, and increase the production by 17 and 26%, respectively.…”