| abstract |
The present invention provides a method for producing optically active hydroxycarboxylic acid monomers by auto-degradation of polyhydroxyalkanoates (PHAs). In particular, the present invention provides a method for producing hydroxycarboxylic acid monomers (mostly optically active in (R)-(-)-configuration) comprising the steps of: (a) synthesizing and accumulating PHAs by culturing various microorganisms; and (b) preparing optically active hydroxycarboxylic acids which are monomers of PHAs, by auto-degradation of PHAs by keeping the cultured microorganism in a degradation solution such as water, salt solution, mixture of water and organic solvents, and buffer solution. The present invention also provides a method for the separation of the prepared (R)-(-)-hydroxycarboxylic acids using liquid chromatography (LC) or high performance liquid chromatography (HPLC), and also provides further purification method by removing impurities from the purely separated (R)-(-)-hydroxycarboxylic acids by organic solvent extraction and powder-making process of drying the purified hydroxycarboxylic acids. The present method is economical since hydroxycarboxylic acids can be efficiently produced with high purity and yield by simple process. Also, the present method is environmentally friendly since organic solvents, which are required in large amounts in conventional methods, are used only in minimal amounts in the present invention. |