Patent US5028703A successfully refreshed from Google Patents.
US5028703A
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Glucan composition and process for preparation thereof
Assignee: Massachusetts Institute of Technology
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Filing: 1989-04-05
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Granted: 1991-07-02
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Expires: 2009-04-05
Abstract
Abstract 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 β(1-6) linkages, or with glucanase to alter the β(1-3) linkages. The glucans have viscosity characteristics dependent upon the strain of yeast utilized and are useful as stabilizers or thickeners.
Inventors
- 👤 Spiros Jamas
- 👤 ChoKyun Rha
- 👤 Anthony J. Sinskey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:44
CPC Classifications
C; C12; C12P; C12P19/00; C12P19/04; C08; C08B; C08B37/00; C08B37/0006; C08B37/0024
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
60 words
Whole glucan particles substantially retaining the in vivo glucan morphology and isolated from glucan-containing cell walls of genetically modified cells, the β(1-6) linkages in said whole glucans being altered sufficiently to provide a significant difference in the resistance to hydrolysis by β(1-3) glucanases compared to the resistance to hydrolysis by β(1-3) glucanases of whole glucans from comparable non-genetically modified cells.
Claim 2
Dependent Claim
60 words
Whole glucan particles substantially retaining the in vivo glucan morphology and isolated from glucan-containing cell walls of genetically modified cells, the β(1-6) linkages in said whole glucans being altered sufficiently to provide a significant difference in the resistance to hydrolysis by β(1-3) glucanases compared to the resistance to hydrolysis by β(1-3) glucanases of whole glucans from comparable non-genetically modified cells.
Claim 3
Dependent Claim
16 words
Altered whole glucan particles of claim 1 which are isolated from a mutated strain of yeast.
Claim 4
Dependent Claim
77 words
Altered whole glucan particles of claim 2 wherein the mutated yeast strain is a mutant strain of Saccharomyces cerevisiae, Saccharomyces delbrueckii, Saccharomyces rosei, Saccaromyces microellipsodes, Saccharomyces carlsbergensis, Saccharomyces bisporus, Saccharomyces fermentati, Saccharomyces rouxii, Schizosaccharomyces pombe, Kluyveromyces lactis, Kluyveromyces fragilis, Kluyveromyces polysporus, Candida albicans, Candida cloacae, Candidatropicalis, Candida utilis, Hansenula wingei, Hansenula arni, Hansenula henricii, Hansenula americana, Hansenula canadiensis, Hansenula capsulata, Hansenula polymorpha, Pichia kluyveri, Pichia pastoris, Pichia polymorpha, Pichia rhodanensis, Pichia ohmeri, Torulopsis bovina and Torulopsis glabrata.
Claim 5
Dependent Claim
17 words
Altered whole glucan particles of claim 3 which are isolated from a mutant strain of Saccharomyces cerevisiae.
Claim 6
Dependent Claim
18 words
Altered whole glucan particles of claim 4 wherein the mutant strain of Saccharomyces cerevisiae comprises Saccharomyces cerevisiae R4.
Claim 7
Dependent Claim
15 words
Altered whole glucan particles of claim 5 containing less than one percent, by weight, protein.
Claim 8
Dependent Claim
15 words
Altered whole glucan particles of claim 1 containing less than one percent, by weight, protein.
Claim 9
Dependent Claim
19 words
Altered whole glucan particles of claim 7 having a particle size of from about 2 to about 10 microns.
Claim 10
Dependent Claim
26 words
Altered whole glucan particles of claim 1 wherein the genetically modified cells comprise glucan-containing cells having DNA which has been genetically modified by in vitro techniques.
Claim 11
Dependent Claim
14 words
Altered whole glucan particles of claim 9 wherein said glucan-containing cells comprise yeast cells.
Claim 12
Dependent Claim
98 words
A process for preparing altered whole glucan particles comprising the steps of: (a) exposing glucan-containing cells to a mutagen under conditions sufficient to produce mutant cells which produce glucans containing β(1-6) linkages sufficiently altered to provide a significant difference in the resistance to hydrolysis by β(1-3) glucanases compared to whole glucans isolated from the non-mutated cells; and (b) isolating altered whole glucan particles from the cell walls of said mutant cells without a prior step of disrupt the cell walls and under conditions sufficient for said isolated whole glucan particles to substantially retain the in vivo glucan morphology.
Claim 13
Dependent Claim
98 words
A process for preparing altered whole glucan particles comprising the steps of: (a) exposing glucan-containing cells to a mutagen under conditions sufficient to produce mutant cells which produce glucans containing β(1-6) linkages sufficiently altered to provide a significant difference in the resistance to hydrolysis by β(1-3) glucanases compared to whole glucans isolated from the non-mutated cells; and (b) isolating altered whole glucan particles from the cell walls of said mutant cells without a prior step of disrupt the cell walls and under conditions sufficient for said isolated whole glucan particles to substantially retain the in vivo glucan morphology.
Claim 14
Dependent Claim
12 words
A process of claim 11 wherein the glucan-containing cells are yeast cells.
Claim 15
Dependent Claim
16 words
A process of claim 12 wherein the yeast cells comprise a strain of mutated Saccharomyces cerevisiae.
Claim 16
Dependent Claim
16 words
A process of claim 13 wherein the mutated strain of Saccharomyces cerevisiae comprises Saccharomyces cerevisiae A364A.
Claim 17
Dependent Claim
24 words
A process of claim 14 wherein step (a) is performed by exposing a cell culture of Saccharomyces cerevisiae A364A yeast cells to ultraviolet radiation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-01 | 1994-12-31 | 1995-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-01 | 1998-12-31 | 1999-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-01 | 2002-12-31 | 2003-07-02 | $7700.00 | Window Closed / Lapsed |