Patents by Inventor ChoKyun Rha
ChoKyun Rha 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).
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Publication number: 20040097463Abstract: Products containing asiatic acid or asiaticoside, and uses thereof, for the treatment of cancer and other proliferative diseases are provided.Type: ApplicationFiled: December 1, 2003Publication date: May 20, 2004Inventors: Se-Kyung Oh, ChoKyun Rha, Azizol Abdul Kadir, Teik Lean Ng
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Publication number: 20040087493Abstract: The invention provides new uses and products for treatment of sexual dysfunction and male infertility. The products include bioactive components of extracts from roots of the plant Eurycoma longifolia mixed in preparations for topical application and administation.Type: ApplicationFiled: December 12, 2003Publication date: May 6, 2004Inventors: T.G. Sambandan, ChoKyun Rha, Azizol Abdul Kadir, Norhaniza Aminudim, Joharl Mohammed Saad
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Patent number: 5811272Abstract: A method has been developed for control of molecular weight and molecular weight dispersity during production of polyhydroxyalkanoates in genetically engineered organism by control of the level and time of expression of one or more PHA synthases in the organisms. The method was demonstrated by constructing a synthetic operon for PHA production in E. coli in which the level of PHA synthase activity could be tightly controlled by placement of the synthase behind an inducible promoter. Modulation of the total level of PHA synthase activity in the host cell by varying the concentration of the inducer, isopropyl .beta.-D-thiogalactoside (IPTG), was found to effect the molecular weight of the polymer produced in the cell. Specifically, high concentrations of synthase activity were found to yield polymers of low molecular weight while low concentrations of synthase activity yielded polymers of higher molecular weight.Type: GrantFiled: July 26, 1996Date of Patent: September 22, 1998Assignee: Massachusetts Institute of TechnologyInventors: Kristi D. Snell, Scott A. Hogan, Sang Jun Sim, Anthony J. Sinskey, Chokyun Rha
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Patent number: 5569483Abstract: A degradation product of a polysaccharide derivative comprising a mixture of oligomers of the polysaccharide derivative, the majority of said oligomers having a molecular weight such that the oligomer conforms to a rod-like configuration.Type: GrantFiled: June 7, 1994Date of Patent: October 29, 1996Assignee: Alko Group Ltd.Inventors: Maritta Timonen, ChoKyun Rha, Timo Vaara, Lindsey Bagley, Sarah Bosdet, Michael Lindley, Tarja Lahtinen, Marja Turunen, Martti Vaara
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Patent number: 5543162Abstract: An insoluble polymeric capsule comprising at least two polymeric components, wherein one of said components is a hydrophilic colloid, and another of said components comprises a degradation product of a cellulose derivative, the degradation product comprising a mixture of oligomers, a majority of said oligomers having a degree of polymerization such that the oligomers conform to a rod-like configuration.Type: GrantFiled: November 23, 1994Date of Patent: August 6, 1996Assignee: Alko Group Ltd.Inventors: Maritta Timonen, Chokyun Rha
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Patent number: 5525368Abstract: A degradation product of a polysaccharide derivative comprising a mixture of oligomers of the polysaccharide derivative, the majority of said oligomers having a molecular weight such that the oligomer conforms to a rod-like configuration.Type: GrantFiled: June 6, 1994Date of Patent: June 11, 1996Assignee: Alko Group Ltd.Inventors: ChoKyun Rha, Timo Vaara, Maritta Timonen, Tarja Lahtinen, Marja Turunen, Martti Vaara, Lindsey Bagley, Sarah Bosdet, Michael Lindley
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Patent number: 5506124Abstract: Three dimensional glucan matrix compositions are prepared by separating growing yeast from its growth medium, subjecting the yeast with cell walls intact to an alkali material, thereby extracting whole glucan particles having an intact cell wall structure. The whole glucans can then, optionally, be treated with acetic acid to alter the .beta.(1-6) linkages, or with glucanase to alter the .beta.(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.Type: GrantFiled: August 17, 1993Date of Patent: April 9, 1996Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 5366755Abstract: A degradation product of a polysaccharide derivative comprising a mixture of oligomers of the polysaccharide derivative, the majority of said oligomers having a molecular weight such that the oligomer conforms to a rod-like configuration.Type: GrantFiled: August 9, 1991Date of Patent: November 22, 1994Inventors: Maritta Timonen, ChoKyun Rha, Timo Vaara, Lindsey Bagley, Sarah Bosdet, Michael Lindley, Tarja Lahtinen, Marja Turunen, Martti Vaara
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Patent number: 5354424Abstract: A paper product treated with a degradation product of a polysaccharide derivative comprising a mixture of oligomers of the polysaccharide derivative, a majority of said oligomers having a degree of polymerization such that the oligomer conforms to a rod-like configuration.Type: GrantFiled: January 24, 1992Date of Patent: October 11, 1994Inventors: Chokyun Rha, Maritta Timonen
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Patent number: 5250436Abstract: Three dimensional glucan matrix compositions are prepared by separating growing yeast from its growth medium, subjecting the yeast with cell walls intact to an alkali material, thereby extracting whole glucan particles having an intact cell wall structure. The whole glucans can then, optionally, be treated with acetic acid to alter the .beta.(1-6) linkages, or with glucanase to alter the .beta.(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.Type: GrantFiled: June 2, 1992Date of Patent: October 5, 1993Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 5110733Abstract: The extraction or purification of biomaterials and other products by liquid-liquid extraction in an aqueous system is enhanced by introducing a particulate polymeric adsorbent into the extraction system and agitating the system, whereupon the adsorbent reversibly binds the product or material to be separated from the product, to form a complex, and the complex preferentially partitions into one of the liquid phases. The complex is then separated, and the product recovered from the complex or the remaining liquid. Ion exchange resins comprising beads or ground particles, of 0.01-10 micrometer average diameter, are representative adsorbents.Type: GrantFiled: December 21, 1989Date of Patent: May 5, 1992Assignee: Rohm and Haas CompanyInventors: Chan W. Kim, Elizabeth M. Robinson, Chokyun Rha
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Patent number: 5082936Abstract: Three dimensional glucan matrix compositions are prepared by separating growing yeast from its growth medium, subjecting the yeast with cell walls intact to an alkali material, thereby extracting whole glucan particles having an intact cell wall structure. The whole glucans can then, optionally, be treated with acetic acid to alter the .beta.(1-6) linkages, or with glucanase to alter the .beta.(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.Type: GrantFiled: January 17, 1989Date of Patent: January 21, 1992Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 5037972Abstract: Three dimensional glucan matrix compositions are prepared by separating growing yeast from its growth medium, subjecting the yeast with cell walls intact to an alkali material, thereby extracting whole glucan particles having an intact cell wall structure. The whole glucans can then, optionally, be treated with acetic acid to alter the .beta.(1-6) linkages, or with glucanase to alter the .beta.(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.Type: GrantFiled: April 3, 1990Date of Patent: August 6, 1991Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 5028703Abstract: Three dimensional glucan matrix compositions are prepared by separating growing yeast from its growth medium, subjecting the yeast with cell walls intact to an alkali material, thereby extracting whole glucan particles having an intact cell wall structure. The whole glucans can then, optionally, be treated with acetic acid to alter the .beta.(1-6) linkages, or with glucanase to alter the .beta.(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.Type: GrantFiled: April 5, 1989Date of Patent: July 2, 1991Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 5008108Abstract: A method for utilizing a purified exocellular polysaccharide, Zooglan, produced by Zoogloea ramigera, as a viscosity modifier, gellant, drag reducing agent, dispersant, flocculant, or emulsifying agent, wherein the properties of the polymer are dependent on, and can therefore be controlled by varying, the pH, the concentration of polymer, the ionic strength of the solution, and the processing parameters such as mechanical shear.The overall conformation of Zooglan, which is responsible for its functional properties, can be manipulated with pH and/or ionic strength of the solution. For example, the intrinsic viscosity of Zooglan (estimated m.w.=2.times.10.sup.7) can vary from 16 to 170 dl/g in aqueous solution as a function of pH between 2-9 and salt concentration between 0 and 1M KCl. Zooglan is a polyelectrolyte above pH 2. The Zooglan chain is relatively stiff, with a stiffness parameter of 0.02. Zooglan solutions at a concentration above 0.Type: GrantFiled: March 28, 1989Date of Patent: April 16, 1991Assignee: Massachusetts Institute of TechnologyInventors: ChoKyun Rha, Pasawadee Pradipasena, TetsuHisa Nakamura, Donald D. Easson, Jr., Anthony J. Sinskey
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Patent number: 4992540Abstract: Three dimensional glucan matrix compositions are prepared by separating growing yeast from its growth medium, subjecting the yeast with cell walls intact to an alkali material, thereby extracting whole glucan particles having an intact cell wall structure. The whole glucans can then, optionally, be treated with acetic acid to alter the .beta.(1-6) linkages, or with glucanase to alter the .beta.(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.Type: GrantFiled: January 17, 1989Date of Patent: February 12, 1991Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 4851393Abstract: A method for utilizing a purified exocellular polysaccharide, Zooglan, produced by Zoogloea ramigera, as a viscosity modifier, gellant, drag reducing agent, dispersant, flocculant, or emulsifying agent, wherein the properties of the polymer are dependent on, and can therefore be controlled by varying, the pH, the concentration of polymer, the ionic strength of the solution, and the processing parameters such as mechanical shear.The overall conformation of Zooglan, which is responsible for its functional properties, can be manipulated with pH and/or ionic strength of the solution. For example, the intrinsic viscosity of Zooglan (estimated m.w.=2.times.10.sup.7) can vary from 16 to 170 dl/g in aqueous solution as a function of pH between 2-9 and salt concentration between 0 and 1M KCl. Zooglan is a polyelectrolyte above pH 2. The Zooglan chain is relatively stiff, with a stiffness parameter of 0.02. Zooglan solutions at a concentration above 0.Type: GrantFiled: July 28, 1986Date of Patent: July 25, 1989Assignee: Massachusetts Institute of TechnologyInventors: ChoKyun Rha, Pasawadee Pradipasena, TetsuHisa Nakamura, Donald D. Easson Jr., Anthony J. Sinskey
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Patent number: 4810646Abstract: Three dimensional glucan matrix compositions are prepared by separating growing Saccharomyces cerevisiae yeast from its growth medium, subjecting the yeast with cell walls intact to aqueous hydroxide and treating the insoluble glucan with acetic acid to alter the .beta.(1-6) linkages. The glucans have viscosity characteristics dependent upon the strain of Saccharomyces cerevisiae utilized and are useful as stabilizer or thickeners.Type: GrantFiled: November 28, 1984Date of Patent: March 7, 1989Assignee: Massachusetts Institute of TechnologyInventors: Spiros Jamas, ChoKyun Rha, Anthony J. Sinskey
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Patent number: 4749620Abstract: Capsules are formed herein a liquified core while avoiding capsule core gelation by adding drops of a solution of either an anionic polymer composition or a cationic polymer composition to a solution of an ionic polymer of opposite charge. The drops contain an active ingredient such as a cell or microorganism capable of producing a biologically active product or can contain a biological or chemical composition. The interface of the ionic polymers form a permeable membrane surrounding the liquid drops.Type: GrantFiled: September 18, 1985Date of Patent: June 7, 1988Assignee: Massachusetts Institute of TechnologyInventors: ChoKyun Rha, Dolores Rodriguez-Sanchez
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Patent number: 4744933Abstract: Capsules are formed herein a liquified core while avoiding capsule core gelation by adding drops of a solution of either an anionic polymer composition or a cationic polymer composition to a solution of an ionic polymer of opposite charge. The drops contain an active ingredient such as a cell or microorganism capable of producing a biologically active product or can contain a biological or chemical composition. The interface of the ionic polymers form a permeable membrane surrounding the liquid drops.Type: GrantFiled: August 16, 1985Date of Patent: May 17, 1988Assignee: Massachusetts Institute of TechnologyInventors: ChoKyun Rha, Dolores Rodriguez-Sanchez