Biotechnological synthesis of long-chain dicarboxylic acids as building blocks for polymers

An important field in sustainable industrial chemistry is the development of new applications for fats and oils. One of the promising applications is the use of fatty acid derivatives, e. g. dicarboxylic acid (DCA), as polymer building blocks. In contrast to conventional plastics, bioplastics are polymers derived from renewable biomass sources. In addition to their contribution to the conservation of fossil resources and reduction in CO2 emissions by waste incineration, many bioplastics are biodegradable. The majority of industrial DCA production for polyamide (PA) and polyester (PE) synthesis is still done via chemical synthesis. While short-chain DCA can be synthesized in high yields, costs of long-chain DCA production rise significantly due to the generation of various by-products and are connected mostly to a costly purification. Thus biotechnology provides novel biochemical approaches for long-chain DCA synthesis that can provide an eco-efficient process alternative. In the present article, strategies for the development of high-level production strains for long-chain DCA are illustrated. Basic strategies for strain development, in order to achieve an effective enrichment of DCA, require the knowledge of the respective biochemical pathways. These are discussed in detail. Furthermore an overview of fermentation strategies and characteristics of corresponding polymers is given.