US3717549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fermentation process for the production of citric acid
Assignee: Pfizer Inc
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Filing: 1971-02-09
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Granted: 1973-02-20
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Expires: 1991-02-09
Abstract
Abstract A process for producing citric acid by aerobically fermenting an aqueous carbohydrate-containing nutrient medium with certain yeast strains.
Inventors
- 👤 F Roberts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:23
CPC Classifications
C; C12; C12P; C12P7/00; C12P7/40; C12P7/44; C12P7/48; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/911; Y10S435/921; Y10S435/93; Y10S435/938; Y10S435/944
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
60 words
A process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of a genus selected from the group consisting of Candida, Endomycopsis, Torulopsis, Hansenula, and Pichia under aerobic conditions in an aqueous carbohydrate-containing medium until a level of at least about 1 gram of citric acid accumulates per liter of said medium, and recovering said citric acid.
Claim 2
Dependent Claim
60 words
A process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of a genus selected from the group consisting of Candida, Endomycopsis, Torulopsis, Hansenula, and Pichia under aerobic conditions in an aqueous carbohydrate-containing medium until a level of at least about 1 gram of citric acid accumulates per liter of said medium, and recovering said citric acid.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein said yeast is a Candida strain.
Claim 4
Dependent Claim
49 words
The process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of the genus Torulopsis under aerobic conditions in an aqueous carbohydrate-containing medium until a level of at least about 1 gram of citric acid accumulates per liter of said medium, and recovering said citric acid.
Claim 5
Dependent Claim
49 words
The process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of the genus Torulopsis under aerobic conditions in an aqueous carbohydrate-containing medium until a level of at least about 1 gram of citric acid accumulates per liter of said medium, and recovering said citric acid.
Claim 6
Dependent Claim
79 words
The process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of the genus Candida under aerobic conditions in an aqueous medium containing molasses as the principal carbohydrate source and containing calcium carbonate, and maintaining a pH between about 1.5 and 8 and a temperature between about 20* and 37*C. during said propagating, until a level of at least about 1 gram of citric acid accumulates per liter of said medium, and recovering said citric acid.
Claim 7
Dependent Claim
79 words
The process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of the genus Candida under aerobic conditions in an aqueous medium containing molasses as the principal carbohydrate source and containing calcium carbonate, and maintaining a pH between about 1.5 and 8 and a temperature between about 20* and 37*C. during said propagating, until a level of at least about 1 gram of citric acid accumulates per liter of said medium, and recovering said citric acid.
Claim 8
Dependent Claim
84 words
The process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of a genus selected from the group consisting of Candida, Endomycopsis, Torulopsis, Hansenula, and Pichia under aerobic conditions in an aqueous carboHydrate-containing medium until a level of at least about 1 gram of citric acid accumulates per liter of said medium, said medium also containing an agent selected from the group consisting of Alpha -chloro-, and Alpha -fluoro-substituted lower alkanoic mono- and dicarboxylic acids and their water-soluble salts and amides.
Claim 9
Dependent Claim
84 words
The process for producing citric acid which comprises propagating a citric acid-accumulating yeast strain of a genus selected from the group consisting of Candida, Endomycopsis, Torulopsis, Hansenula, and Pichia under aerobic conditions in an aqueous carboHydrate-containing medium until a level of at least about 1 gram of citric acid accumulates per liter of said medium, said medium also containing an agent selected from the group consisting of Alpha -chloro-, and Alpha -fluoro-substituted lower alkanoic mono- and dicarboxylic acids and their water-soluble salts and amides.
Claim 10
Dependent Claim
10 words
The process of claim 5 wherein said agent is fluoroacetate.
References Cited (Backward Citations)
US2993838A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-20 | 1976-08-21 | 1977-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-20 | 1980-08-21 | 1981-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-20 | 1984-08-21 | 1985-02-20 | $7700.00 | Window Closed / Lapsed |