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Challenges of the Glucosamine Process


Efforts to improve glucosamine production met with many challenges. One of the major challenges was glucosamine degradation. Degradation was spontaneous and was faster at higher pH (Figure 5). Over 65% of glucosamine was degraded after 53 hours at pH 7, the normal pH for E. coli growth.

Another challenge was growth inhibition of the E. coli host by high concentration of glucosamine in the growth medium (Figure 6). Growth inhibition was at least partially due to the nagB deletion in the genome. Glucosamine degradation products also contributed to growth inhibition.

Figure 5. Degradation of Glucosamine in a Non-Inoculated Medium Adjusted to Different pHs

Degradation of Glucosamine


Figure 6. Growth Inhibition by Glucosamine

Growth Inhibition