Patent US2490509A successfully refreshed from Google Patents.
Patent US1632491A successfully refreshed from Google Patents.
US4359534A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Conversion of D-xylose to ethanol by the yeast Pachysolen tannophilus
Assignee: United States Department of Agriculture
•
Filing: 1981-04-28
•
Granted: 1982-11-16
•
Expires: 2001-04-28
Abstract
Abstract A method is disclosed for converting D-xylose to ethanol relying on the unique ability of the yeast Pachysolen tannophilus to ferment this five-carbon sugar without the use of added enzymes. This process will be particularly useful in the production of ethanolic fuel from plant biomass.
Inventors
- 👤 Cletus P. Kurtzman
- 👤 Rodney J. Bothast
- 👤 James E. VanCauwenberge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:50
CPC Classifications
C; C12; C12P; C12P7/00; C12P7/02; C12P7/04; C12P7/06; C12P7/08; C12P7/10; Y; Y02; Y02E; Y02E50/00; Y02E50/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
67 words
A method for producing ethanol from a xylose-containing substance comprising the following steps: a. inoculating a medium containing said substance with the yeast Pachysolen tannophilus; b. fermenting said substance in said inoculated medium under conditions favorable for cell viability and for conversion of xylose to ethanol by the yeast, thereby enriching said medium with ethanol; and c. recovering said ethanol-enriched medium from the fermentation of step (b).
Claim 2
Independent Claim
67 words
A method for producing ethanol from a xylose-containing substance comprising the following steps: a. inoculating a medium containing said substance with the yeast Pachysolen tannophilus; b. fermenting said substance in said inoculated medium under conditions favorable for cell viability and for conversion of xylose to ethanol by the yeast, thereby enriching said medium with ethanol; and c. recovering said ethanol-enriched medium from the fermentation of step (b).
Claim 3
Dependent Claim
32 words
A method as described in claim 1 wherein the yeast Pachysolen tannophilus is a strain selected from the group consisting of NRRL Y-2460, NRRL Y-2461, NRRL Y-2462, NRRL Y-2463, and NRRL Y-6704.
Claim 4
Dependent Claim
16 words
A method as described in claim 1 wherein said xylose-containing substance is a lignocellulosic degradation product.
Claim 5
Dependent Claim
15 words
A method as described in claim 1 wherein said xylose-containing substance is a hemicellulose hydrolysate.
Claim 6
Dependent Claim
33 words
A method as described in claim 1 wherein the medium of step (a) also contains glucose and wherein the fermentation conditions of step (b) are also favorable for fermenting said glucose to ethanol.
Claim 7
Dependent Claim
20 words
A method as described in claim 1 wherein the fermentation conditions of step (b) are also favorable for cell growth.
Claim 8
Dependent Claim
40 words
A method as described in claim 6 wherein the medium is oxygenated, the pH is controlled within the range of about 2 to about 7, and the temperature is maintained within the range of about 10° to about 35° C.
Claim 9
Dependent Claim
24 words
A method as described in claim 6 wherein the pH is controlled at about 2.5 and the temperature is maintained at approximately 32° C.
Claim 10
Dependent Claim
31 words
A method as described in claim 1 wherein prior to the inoculation in step (a), said xylose is present in said medium at a concentration of less than about 150 g./l.
Claim 11
Dependent Claim
14 words
A method as described in claim 9 wherein said concentration is about 50 g./l.
Claim 12
Dependent Claim
21 words
A method as described in claim 1 and further comprising the step of isolating aqueous ethanol from the recovered ethanol-enriched medium.
References Cited (Backward Citations)
US2481263A
Cited
GB884822A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-11-15 | 1986-05-17 | 1986-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-15 | 1990-05-17 | 1990-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-15 | 1994-05-17 | 1994-11-16 | $7700.00 | Window Closed / Lapsed |