Patents by Inventor Pieter L. Kerkhoffs

Pieter L. Kerkhoffs has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Process for the preparation of L-alpha-amino acid and d-alpha-amino acid amide
    Patent number: 4880737
    Abstract: The invention relates to a process for preparation of L-.alpha.-amino acid and D-.alpha.-amino acid amide from DL-.alpha.-amino-acid amide by contacting the DL-.alpha.-amino acid amide in an aqueous solution with an .alpha.-amino acid amidase containing preparation obtained from a culture of Pseudomonas putida in the presence of traces of bivalent metal ions as activator, characterized in that the aqueous solution also contains a potassium salt selected from the group consisting of potassium sulphate and potassium chloride.The invention further relates to a process for the preparation of L-.alpha.-amino acid and D-.alpha.- amino acid amide starting from the corresponding aldehyde, potassium cyanide and ammoniumsulphate, subsequent treatment with a ketone and potassiumhydroxide and finally subjecting to enzymatic hydrolysis with a preparation obtained from Pseudomonas putida.
    Type: Grant
    Filed: October 28, 1985
    Date of Patent: November 14, 1989
    Assignee: Stamicarbon B.V.
    Inventors: Pieter L. Kerkhoffs, Wilhelmus H. J. Boesten
  • Preparation of fructose
    Patent number: 4277563
    Abstract: Fructose in a purified form is recovered from plant parts containing fructose polymer, such as inulin, by treatment of the mixed plant parts with an aqueous solution of fructose polymer hydrolyzing enzyme, such as inulase, followed by recovering the remaining solid plant parts and recovering fructose crystals from the aqueous solution.
    Type: Grant
    Filed: November 19, 1979
    Date of Patent: July 7, 1981
    Assignee: Stamicarbon, B.V.
    Inventor: Pieter L. Kerkhoffs