Glycerol bioconversion

Chen X, Xiu ZL, Wang JF, Zhang DJ, Xu P. (2003a). Stoichiometric analysis and experimental investigation of glycerol bioconversion to 1,3-propanediol by Klebsiella pneumoniae under microaerobic conditions. Enzyme Micmbiol Technol, 33, 386-394. 

Xiu ZL, Zeng AP, An LJ. (2000). Mathematical modehng of kinetics and research on multi-phcity of glycerol bioconversion to 1,3-propanediol. J Dalian Univ Technol, 40, 428-433. 

Microbial production of 3-hydroxypropionaldehyde from glycerol bioconversion. Chem. Biochem. Eng. Q.,... 

Ltithi-Peng, Q., Dileme, F.B., Puhan, Z., 2002. Effect of glucose on glycerol bioconversion by Lactobacillus reuteri. Appl. Microbiol. Biotechnol 59,289-296. 

Bacterial fermentation at a large scale leads to the formation of organic by-products. Chen et al. (2014) investigated the glycerol bioconversion to 3-HP production by the malonyl-coA pathway in Saccharomyces cerevisae to avoid organic by-product formation. Malonyl-coA precursor formed from acetyl coA is an intermediate that leads to forward and reverse directions of channeling of carbon fluxes that utilize various sugars. An improved 3-HP production was evident due to the reconstruction of the malonyl-coA pathway that increased the availability of redox equivalents. 

Hirschmann, S., Baganz, K., Koschik, I. and Vorlop, K.-D. 2005. Development of an Integrated Bioconversion Process for the Production of 1,3-Propanediol from Raw Glycerol Waters. 

Figure 2-7 Plane of Symmetry of a Glycerol Molecule (Top) and Mirror Image of Two Enantiomers of a Mono-Acylglycerol (bottom). Source Reprinted with permission from P. Ville-neuve and T.A. Foglia, Lipase Specificities Potential Application in Bioconversions, Inform, 8, pp. 640-650, 1997, AOCS Press.

While sugar alcohols are not common, large scale, they may be used in bioconversions such as from glycerol. Methane, methanol and n-alkanes have been used in biomass production. 

An example of aldehyde formation is the production of isovaleraldehyde by Gluconobacter oxydans R (Fig. 16.2-45) 202, 206. Glycerol-grown Gluconobacter oxydans slowly oxidizes 3-methyl-l-butanol to isovaleraldehyde, with yields of over 90%. The product was recovered by bisulphite trapping or cold traps 202. Extractive bioconversion in a hollow-fiber membrane bioreactor allowed continuous produc-... 

One of the common side effects observed during extractive bioconversion is the accumulation of unwanted by-products in the system which may affect the productivity during continuous operation (14). The build up of glycerol and other non-volatile products was shown to decrease the ethanol yields during repeated fermentations in a two-phase system (12). The problem was, however, solved by dialysing the fermentation broth and also adding more yeast cells. It appears that the combination of ultrafiltration with the phase system may circumvent the problem of by-product inhibition in most of the cases. 

Fig. 2 Xylitol (a), arabitol (b), and glycerol (c) production during xylose bioconversion to xylitol by P. stipitis D-xylulokinase mutant in medium YPX...

Hirschmann, S. K. Baganz I. Koschik K.-D. Vorlop. Development of an integrated bioconversion process for the production of 1,3-propanediol from raw glycerol esters. Landhauforschung Vdlken-rode 2005, 55, 261-267. 

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