Glycerol engineering

Wang and coworkers first reported the use of these monomers as a novel elastomeric material for potential application in soft tissue engineering in 2002. The molar ratio of glycerol to sebacic acid they used was 1 1. The equimolar amounts of the two monomers were synthesized by polycondensation at 120°C for three days. The reaction scheme is shown in Scheme 8.1. To obtain the elastomers, they first synthesized a prepolymer and then poured an anhydrous 1,3-dioxolane solution of the prepolymer into a mold for curing and shaping under a high vacuum. 

A new route with the potential of further lowering PDO cost is the enzymatic fermentation [17, 18] of glycerol and alcohol. This process is still under development by Du Pont and Genecore International. With advances in biogenetic engineering, new strains of engineered bacteria have improved the yield and selectivity of the process to the point where this route is ready for pilot plant scale-up. 

Zhu, M. M. Lawman, P. D. Cameron, D. C. Improving 1,3-propanediol production from glycerol in a metabolically engineered E.coli by reducing accumulation of glycerol-3-phosphate, Biotechnol. Prog., 2002, 18, 694-699. 

Pachauri, N. and He, B. (2006) Valued-added utilisation of crude glycerol from biodiesel production a survey of current research, American Society of Agricultural and Biological Engineers Annual Meeting, Portland, USA. 

Torres et al. (2006) reported a novel microwave processing technique to produce biodegradable scaffolds for tissue engineering from different types of starch-based polymers. Potato, sweet potato, com starch, and non-isolated amaranth and quinoa starch were used along with water and glycerol as plasticizers to produce porous stmctures. Figure 16.1 shows the manufacturing procedure of microwaved starch scaffolds. 

Zang et al. developed a peptide-based polyurethane scaffold for tissue engineering. LDI was reacted with glycerol and upon reaction with water produced a porous sponge due to liberation of CO2. Initial cell growth studies with rabbit bone marrow stromal cells showed that the polymer supported cell growth. 

These dendrimers expand the repertoire of polymers available for study. Current investigations are primarily limited to linear polymers that possess ill-defined solution structures and fewer hydroxyl groups for further modification. The introduction of biocompatible building blocks (e.g., glycerol and lactic acid) augments the favorable and already known physical properties of dendrimers. These properties are likely to facilitate the design of new materials for specific biomedical and tissue engineering applications. 

Behr A, Leschinski J, Awungacha C, Simic S, Knoth T (2009) Telomerization of butadiene with glycerol reaction control through process engineering, solvents, and additives. ChemSusChem 2 71-76... 

Several microorganisms could be adapted or engineered to consume glycerol as a carbon source for the production of chemicals that could be used either as end products or as important building blocks. Compared to saccharides, there are... 

Dharmadi, Y., Murarka, A. and Gonzalez, R. 2006. Anaerobic Fermentation of Glycerol by Escherichia Coli A New Platform for Metabolic Engineering. Biotechnol. Bioeng., 94, 821— 829. 

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