摘要:
This invention relates to the enantioselective biologically-catalyzed hydrolysis of certain racemic nitriles to the corresponding R- or S-amides, chemically or biologically-catalyzed hydrolysis of the amides to the corresponding R- or S-acids in a batch process or in a continuous process that employs racemization and recycling of enantiomeric nitrile intermediates, the racemic nitriles being selected from the group, A--C(R.sup.1)(R.sup.2)CN, wherein A, R.sup.1 and R.sup.2 are as defined in the text, as well as certain biological materials employed to catalyze the process.
摘要:
A process for the production of pyruvic acid involving the enzymatic reaction of L-lactic acid and oxygen in an aqueous solution in the presence of catalysts glycolate oxidase ((S)-2-hydroxy-acid oxidase, EC 1.1.3.15) and catalase (EC 1.11.1.6). High yields of pyruvate at high purity can be achieved at commercially acceptable concentration without substantial product inhibition of the enzyme.
摘要:
A process for the production of glyoxylic acid involving the enzymatic oxidation of glycolic acid. The process provides a commercially practical method involving the reaction of glycolic acid in an aqueous solution at a starting concentration range of 200 mM to 2,500 mM in the presence of oxygen, glycolate oxidase and catalase at a pH of 7 to 10 and in the presence of an amine such as ethylenediamine, or tris(hydroxymethyl)-methylamine.
摘要:
A process for the production of glyoxylic acid by reacting glycolic acid with oxygen in an aqueous solution in the presence of an amine buffer capable of forming a chemical adduct with glyoxylic acid, and glycolate oxidase and catalase immobilized or co-immobilized on an insoluble support is disclosed. The reaction is carried out at a pH of 7 to 10, preferably 8 to 9.5, an initial concentration of glycolic acid of 200 to 2500 mM, a concentration of amine wherein the initial mole ratio of amine to glycolic acid is within the range of 1.0 to 3.0, a concentration of immobilized catalase of 50 to 100,00 IU/mL, preferably 350 to 14,000 IU/mL, an oxygen pressure of up to 50 atmospheres, preferably 15 atmospheres, an immobilized glycolate oxidase concentration of about 0.01 to 10 IU/mL, preferably about 0.1 to 4 IU/mL, and a temperature of 0.degree. to 40.degree. C. preferably 5.degree. to 15.degree. C. Preferred insoluble immobilization supports are Eupergit C-250L and Eupergit C (Oxirane acrylic beads).
摘要:
A process or the production of glyoxylic acid involving the enzymatic oxidation of glycolic acid. The process provides a commercially practical method involving the reaction of glycolic acid in an aqueous solution at a starting concentration range of 200 mM to 2,500 mM in the presence of oxygen, glycolate oxidase and catalase at a pH of 7 to 10.
摘要:
The invention provides a process for producing mixtures of glyoxylate and a dialkyl aminomethylphosphonate and the subsequent production of N-(phosphonomethyl)glycine, also known as glyphosate. The process comprises preparing in situ a mixture of glyoxylate and a dialkyl aminomethylphosphonate (DEAMPA) by enzymatically reacting glycolic acid (glycolate) and oxygen in an aqueous solution in the presence of a dialkyl aminomethylphosphonate and catalysts consisting of glycolate oxidase and catalase. The resulting mixture can be hydrogenated and then subjected to hydrolysis to produce N-(phosphonomethyl)glycine, a post-emergent phytotoxicant and herbicide.
摘要:
An improved enzymatic process for reacting glycolic acid and oxygen in an aqueous solution in the presence of aminomethylphosphonic acid wherein the improvement comprises using a microbial cell catalyst that expresses glycolate oxidase (e.g., Pichia pastoris, Hansenula polymorpha, Aspergillus nidulans, or Escherichia coli) and endogenous catalase; soluble catalase may also be included. The resulting mixtures are useful intermediates in the production of N-(phosphonomethyl)glycine.
摘要:
This invention concerns esters of unsymmetrically 2-substituted glycolic acid dimers, a process for their preparation and their use in the preparation of unsymmetrically 3,6-substituted 1,4-dioxane-2,5-diones.
摘要:
A process for the production of glyoxylic acid by reacting glycolic acid and oxygen in an aqueous solution at pH 7-10 in the presence of the enzyme glycolate oxidase and a non-enzymatic catalyst for the decomposition of hydrogen peroxide, and an amine buffer capable of forming a chemical adduct with glyoxylic acid.
摘要:
This invention concerns esters of unsymmetrically 2-substituted glycolic acid dimers, a process for their preparation and their use in the preparation of unsymmetrically 3,6-substituted 1,4-dioxane-2,5-diones.