US3878093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separating yeast and/or bacterial cells from a liquid medium
Assignee: Imperial Chemical Industries Ltd
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Filing: 1973-02-23
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Granted: 1975-04-15
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Expires: 1993-02-23
Abstract
Abstract A method for separating bacterial cells from an aqueous medium wherein the cells are flocculated by treating the medium with an alkali to raise its pH to a value within the range 8 to 11 and/or heating the medium to a temperature within the range 50* to 200*C and thereafter treating the medium with an acid to lower its pH to a value within the range 2 to 5. The flocculated cells may be separated by e.g. settling or flotation.
Inventors
- 👤 Diamond Pirbhai Kanani
- 👤 Peter John Sherrington
- 👤 David Charles Steer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:46
CPC Classifications
C; C12; C12N; C12N1/00; C12N1/02; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/829; Y10S435/83; Y10S435/832; Y10S435/834; Y10S435/874; Y10S435/875; Y10S435/876; Y10S530/00; Y10S530/82; Y10S530/823; Y10S530/824; Y10S530/825; Y10S530/827; Y10S530/829
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
59 words
A METHOD FOR SEPARATING BACTERIAL CELLS FROM AN AQUEOUS MEDIUM WHEREIN THE CELL ARE FLOCCULATWD BY HEATING THE MEDIUM TO A TEMPERATURE WITHIN THE RANGE 50* TO 200*C AND THEREAFTER LOWERING THE PH OF THE MEDIUM TO A VALUE WITHIN THE RANGE 2 TO 5 BY TREATMENT WITH AN ACID, AND THE FLOCCULATED CELLS ARE SEPARATED FROM THE MEDIUM.
Claim 2
Independent Claim
59 words
A METHOD FOR SEPARATING BACTERIAL CELLS FROM AN AQUEOUS MEDIUM WHEREIN THE CELL ARE FLOCCULATWD BY HEATING THE MEDIUM TO A TEMPERATURE WITHIN THE RANGE 50* TO 200*C AND THEREAFTER LOWERING THE PH OF THE MEDIUM TO A VALUE WITHIN THE RANGE 2 TO 5 BY TREATMENT WITH AN ACID, AND THE FLOCCULATED CELLS ARE SEPARATED FROM THE MEDIUM.
Claim 3
Dependent Claim
33 words
A method according to claim 1 wherein before the medium is heated the pH of the medium is raised to a value within the range 8 to 11 by treatment with an alkali.
Claim 4
Dependent Claim
41 words
A method according to claim 1 wherein the bacterial cells belong to a strain of a species selected from the group consisting of Pseudomonas fluorescens, Pseudomonas diminuta, Alcaligenes faecalis, Pseudomonas Aeroginosa, Bacillus cereus, Pseudomonas methylotropha and Arthrobacter Nov NRRL B 3728.
Claim 5
Dependent Claim
31 words
A method according to claim 3 wherein the strain is selected from the group consisting of strains NRRL B. 5352 to 5364 and naturally and artifically derived mutants of these strains.
Claim 6
Dependent Claim
20 words
A method according to claim 2 wherein the pH is raised to a value within the range 8 to 9.
Claim 7
Dependent Claim
19 words
A method according to claim 1 wherein said heating is at a temperature within the range 70* to 90*C.
Claim 8
Dependent Claim
29 words
A method according to claim 1 wherein after said heating the medium is cooled to a temperature within the range 20* to 30*C before being treated with the acid.
Claim 9
Dependent Claim
25 words
A method according to claim 1 wherein during the acid treatment step the pH is reduced to a value within the range 2.5 to 4.5.
Claim 10
Dependent Claim
19 words
A method according to claim 1 which forms a step in a process for the continuous production of biomass.
References Cited (Backward Citations)
US3781264A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |