Processes for the manufacture of D(-)-3-hydroxybutyric acid and D(-)-3-hydroxybutyric acid producing mutants
AssigneeAgroferm AG
InventorRobert M. Lafferty
Life of this patent
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Abstract
The invention relates to a process of manufacturing D(-)-3-hydroxybutyric acid by breeding microorganisms capable of producing said acid in a nutrient medium containing certain specific carbon source; bacterial strains especially suitable in carrying out the process; an application of the process for obtaining such microorganisms; and uses of thus produced acid.
Claims7
A process for producing D(-)-3-hydroxybutyric acid which comprises cultivating a mutant microorganism on an aqueous nutrient medium containing trace elements, an assimilable nitrogen source and a carbon source selected from the group consisting of carbon dioxide, glucose, fructose, saccharose, lactose, molasses, whey, methanol, ethanol, glycerin and spent lye from caprolactam synthesis under conditions and for a time sufficient to produce said D(-)-3-hydroxybutyric acid and isolating said D(-)-3-hydroxybutyric acid from the medium, wherein said mutant microorganism does not form 3-hydroxybutyric acid dehydrogenase and produces at least 100 mg/liter of D(-)-3-hydroxybutyric acid when cultivated on said nutrient medium for 30 hours at a temperature between 25.degree. and 40.degree. C. and at a pH value between 4 and 8.
A process for producing a microorganism mutant capable of converting into D(-)-3-hydroxybutyric acid a maximum amount of a carbon source selected from the group consisting of carbon dioxide, glucose, fructose, saccharose, lactose, molasses, whey, methanol, ethanol, glycerin and spent lye from caprolactam synthesis within a minimum space of time, which comprises (1) subjecting a microorganism capable of excreting butyric acid or D(-)-3-hydroxybutyric acid, or of accumulating poly(D-3-hydroxybutyric acid), and which does not form the enzyme 3-hydroxybutyric acid dehydrogenase, to the action of a mutagenic agent, (2) selecting from the mutants thus obtained those which cannot metabolise D(-)-3-hydroxybutyric acid and (3) selecting from the thus obtained mutants those which are capable of producing at least 100 mg of D(-)-3-hydroxybutyric acid per liter of the nutrient medium within 30 hours when cultivated at a temperature of approximately 25.degree.-40.degree. C. and a pH value of approximately 4-8 in an aqueous nutrient medium which contains a carbon source as specified above.
Dependencies are inferred from the claim text.