Patents by Inventor Kyoko Koizumi

Kyoko Koizumi 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).

  • Branched cyclodextrins and method for producing them
    Patent number: 5763598
    Abstract: Disclosed are novel branched cyclodextrins having any of an N-acetylglucosamine group, a glucosaminyl group, an N-acetylgalactosaminyl group and a galactosaminyl group as bonded to the hydroxyl group of the cyclodextrin ring by .beta.-bonding therebetween, and their salts. The novel branched cyclodextrins are produced by reacting a solution containing a cyclodextrin and an N-acetylglucosamine or N-acetylgalactosamine with an N-acetylhexosaminidase, and optionally deacetylating the resulting product.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: June 9, 1998
    Assignee: Ensuiko Sugar Refining Co., Ltd.
    Inventors: Kenichi Hamayasu, Tetsuya Ito, Koki Fujita, Kozo Hara, Kyoko Koizumi, Toshiko Tanimoto, Hirofumi Nakano, Sumio Kitahata
  • Method of preparing a mannosyl-cyclodextrin
    Patent number: 5622844
    Abstract: A method of producing a mannosyl-cyclodextrin having a mannosyl group bonded to the hydroxyl group of the glucosyl group of a cyclodextrin via an alpha-bond. The method includes treating a liquid containing a cyclodextrin and an alpha-mannosyl compound with an alpha-mannosyl transfer agent.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: April 22, 1997
    Assignees: Ensuiko Sugar Refining Co., Ltd., Sumio Kitahata
    Inventors: Sumio Kitahata, Koji Hara, Koki Fujita, Nobuhiro Kuwahara, Kyoko Koizumi
  • Galactosyl and mannosyl cyclodextrins
    Patent number: 5623071
    Abstract: A cyclodextrin having a galactosyl group which is bonded to a 6-hydroxyl group of a glucosyl group of the cyclodextrin via an .alpha.-bond or a .beta.-bond; a cyclodextrin having a mannosyl group which is bonded to a 6-hydroxyl group of the cyclodextrin via an .alpha.-bond.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: April 22, 1997
    Assignees: Ensuiko Sugar Refining Co., Ltd., Sumio Kitahata
    Inventors: Sumio Kitahata, Koji Hara, Koki Fujita, Nobuhiro Kuwahara, Kyoko Koizumi
  • Method of producing a galactosyl-cyclodextrin
    Patent number: 5523218
    Abstract: Disclosed are (1) a novel galactosyl-cyclodextrin having a galactosyl group as bonded to the hydroxyl group of the glucosyl group of a cyclodextrin via an .alpha.-bond and a method of producing said galactosyl-cyclodextrin; (2) a novel galactosyl-cyclodextrin having a galactosyl group as bonded to the hydroxyl group of the glucosyl group of a cyclodextrin via a .beta.-bond and a method of producing said galactosyl-cyclodextrin; and (3) a novel mannosyl-cyclodextrin having a mannosyl group as bonded to the hydroxyl group of the glucosyl group of a cyclodextrin via an .alpha.-bond and a method of producing said mannosyl-cyclodextrin. The new branched cyclodextrins are expected to be widely useful in various fields of drug industry, food industry and cosmetic industry.
    Type: Grant
    Filed: December 30, 1994
    Date of Patent: June 4, 1996
    Assignees: Ensuiko Sugar Refining Co., Ltd., Sumio Kitahata
    Inventors: Sumio Kitahata, Koji Hara, Koki Fujita, Nobuhiro Kuwahara, Kyoko Koizumi
  • Method of preparing hetero-branched cyclodextrins
    Patent number: 5463039
    Abstract: A method of preparing a hetero-branched cyclodextrin comprising a glucosyl or a maltosyl group side chain and a mannosyl group .alpha.-bonded to a hydroxyl group of the glucosyl group or the maltosyl group of the side chain, the method involving reacting a liquid containing a branched cyclodextrin having a glucosyl or maltosyl group as the side chain and an .alpha.-mannosyl compound with an .alpha.-mannosyl transfer enzyme.
    Type: Grant
    Filed: June 21, 1994
    Date of Patent: October 31, 1995
    Assignees: Ensuiko Sugar Refining Co., Ltd., Osaka-shi, Kyoko Koizumi
    Inventors: Koji Hara, Koki Fujita, Nobuhiro Kuwahara, Sumio Kitahata, Kyoko Koizumi
  • Hetero-branched cyclodextrins
    Patent number: 5356884
    Abstract: A hetero-branched cyclodextrin (CD) having a glucosyl or maltosyl group as the side chain, in which a mannosyl group is .alpha.-bonded to the hydroxyl group of the glucosyl group of the side chain; and a method of efficiently preparing the same by reacting a branched cyclodextrin with an .alpha.-mannosidase. The hetero-branched CDs are useful in various fields such as in drugs, foods and cosmetics.
    Type: Grant
    Filed: October 8, 1992
    Date of Patent: October 18, 1994
    Assignees: Ensuiko Sugar Refining Co., Ltd., Osaka-shi, Kyoko Koizumi
    Inventors: Koji Hara, Koki Fujita, Nobuhiro Kuwahara, Sumio Kitahata, Kyoko Koizumi
  • Cephalosporin derivatives, and antibacterial drugs containing the derivatives
    Patent number: 4285939
    Abstract: New cephalosporin derivatives represented by the general formula: ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 each represents hydroxy, acyloxy, and hydrogen provided that two or three of R.sub.1, R.sub.2, and R.sub.3 are not hydrogen at the same time, and their salts, and processes for the preparation thereof. The cephalosporin derivatives of the present invention are useful as antibacterial drugs.
    Type: Grant
    Filed: April 7, 1980
    Date of Patent: August 25, 1981
    Assignee: Eisai Co., Ltd.
    Inventors: Yoshimasa Machida, Isao Saito, Motosuke Yamanaka, Seiichiro Nomoto, Shigeto Negi, Kyosuke Kitoh, Kanemasa Katsu, Yukio Ohya, Takeshi Suzuki, Kyoko Koizumi