US4996153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat-stable, salt-tolerant microbial xanthanase
Assignee: United States Department of Agriculture
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Filing: 1989-08-29
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Granted: 1991-02-26
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Expires: 2009-08-29
Abstract
Abstract A novel mixed bacterial culture isolated from soil by enrichment culture techniques produces a xanthanase enzyme complex which is stable to 65° C. in the presence of salt. These properties render the heat-stable, salt-tolerant zanthanase useful for in situ degradation of xanthan gum in petroleum recovery fluids and other thickened industrial brines.
Inventors
- 👤 Martin C. Cadmus
- 👤 Morey E. Slodki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:57
CPC Classifications
C; C12; C12P; C12P39/00; C12N; C12N1/00; C12N1/20; C12N1/205; C12N9/00; C12N9/88; C12Y; C12Y402/00; C12Y402/02; C12Y402/02012; C12R; C12R2001/00; C12R2001/01; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/829
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
41 words
A heat stable, salt-tolerant xanthanase contained in, or recovered from, a fermentation broth of a culture of NRRL B-18445 and characterized by the property of retaining approximately 100% of its original activity upon being heated at 55° C. for 20 minutes.
Claim 2
Dependent Claim
41 words
A heat stable, salt-tolerant xanthanase contained in, or recovered from, a fermentation broth of a culture of NRRL B-18445 and characterized by the property of retaining approximately 100% of its original activity upon being heated at 55° C. for 20 minutes.
Claim 3
Dependent Claim
14 words
A xanthanase as described in claim 1 wherein said xanthanase is a single enzyme.
Claim 4
Dependent Claim
15 words
A xanthanase as described in claim 1 wherein said xanthanase is a complex of enzymes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-25 | 1994-08-27 | 1995-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-25 | 1998-08-27 | 1999-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-25 | 2002-08-27 | 2003-02-26 | $7700.00 | Window Closed / Lapsed |