1. Field of the Invention
The present invention relates to a process for the preparation of a dicarboxylic acid from a fatty acid derivative using a thermophilic microorganism.
2. Description of Prior Art
Dicarboxylic acids are valuable substances as raw material for the production of synthetic resins, high-quality lubricants, plasticizers, or perfumes. However, the number of carbon atoms of the dicarboxylic acids prepared by the chemical synthesis has been limited, that is, it has been difficult to prepare dicarboxylic acids containing 12 or more carbon atoms. Thus a process for the preparation of dicarboxylic acids by fermentation using microorganisms, in place of the chemical synthesis, has been attracting attention recently.
Most of the microorganisms conventionally employed in the preparation of dicarboxylic acids are yeasts such as microorganisms of the genus Candida (see Japanese Patent Publication No. 19630/1975) or the genus Pichia (see Japanese Patent Publication No. 24392/1970). Only a microorganism of the genus Corynebacterium has been found as a bacterium that can produce dicarboxylic acids (see Japanese Patent Publication No. 17075/1981).
Many fatty acid derivatives, which are used as the substrate for the preparation of a dicarboxylic acid, have a melting point of 40.degree. C. or above. Development of microorganisms that can be employed at temperatures of 40.degree. C. or higher is, therefore, of great interest. Cultivation at high temperatures brings about many advantages, for example, reduction of cooling cost, reduced probability of contamination with germs, decrease in the viscosity of the substrate, increase in the efficiency of contact between the substrate and the microorganism, and the like. However, there have been no microorganisms that can be cultivated at temperatures around 45.degree. C.