Production of ethanol by yeast using xylulose

• US 4,490,468 A
• Filed: 04/23/1980
• Issued: 12/25/1984
• Est. Priority Date: 04/23/1980
• Status: Expired due to Term

• Current Assignee: Purdue Research Foundation (The Trustees of Purdue University (d/b/a Purdue University))
• Original Assignee: Purdue Research Foundation (The Trustees of Purdue University (d/b/a Purdue University))
• Inventors: Chen, Li Fu, Tsao, George T., Flickinger, Michael C., Gong, Cheng Shung
• Primary Examiner(s): Penland, R. B.
• Application Number:
  US06/143,146
• Time in Patent Office: 1,707 Days
• Field of Search: 435/94, 435/927, 435/161, 435/930, 435/162, 435/938, 435/163, 435/940, 435/105, 435/172, 435/255, 435/256, 435/813, 435/234
• US Class Current: 435/161
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y10S 435/921 Candida
• CPC Class Codes: Y10S 435/93 Hansenula
• CPC Class Codes: Y10S 435/938 Pichia
• CPC Class Codes: Y10S 435/94 Saccharomyces

Abstract

Ethanol is produced by the fermentation of xylulose using yeast under fermentative conditions.

Claims

1. A process for the production of ethanol which comprises fermenting xylulose under fermentative conditions at a pH ranging from 3.0 to 9.0 and a temperature ranging from about 5°

to 45°

C. with a yeast selected from the genus consisting of Saccharomyces, Candida, Torula, Schizosaccharomyces, Pichia and Hensenula.

2. A process according to claim 1 wherein said yeast is from the genus Saccharomyces.

3. A process according to claim 1 wherein said pH is from about 4.0 to 6.0.

4. A process according to claim 1 wherein the temperature ranges from about 24°

to 35°

C.

5. A process according to claim 1 wherein said xylulose is obtained by isomerization of xylose.

6. A process according to claim 5 wherein isomerization and fermentation are carried out simultaneously.

7. A process for the production of ethanol from xylose which comprises the steps of:

(a) isomerizing xylose to form xylulose; and

(b) fermenting said xylulose according to the process of claim 1 whereby ethanol is produced.

8. A process according to claim 7 where step (a) is carried out in the presence of glucose isomerase or xylose isomerase.

9. A process according to claim 5 wherein steps (a) and (b) are carried out simultaneously.