Multi-enzyme product with glucoamylase, proteolytic and xylanase activities and method for producing same by solid state fermentation of wheat bran with aspergillus niger

• US 20020037342A1
• Filed: 07/24/2001
• Published: 03/28/2002
• Est. Priority Date: 01/25/1999
• Status: Active Grant

• Current Assignee: Gie Agro Industrie
• Original Assignee: Gie Agro Industrie
• Inventors: Baret, Jean-Luc Alain, Guy, Duchiron, Francis Lucien, Labeille, Pierre Jean
• Granted Patent: US 6,667,066 B2
• Time in Patent Office: Days
• US Class Current: 426/61
• CPC Class Codes: C12N 1/14 Fungi culture of mushrooms A01G18/00; as new plants A01H15/00; Culture media therefor
• CPC Class Codes: C12N 9/2428 Glucan 1,4-alpha-glucosidase (3.2.1.3), i.e. glucoamylase
• CPC Class Codes: C12N 9/2482 Endo-1,4-beta-xylanase (3.2.1.8)
• CPC Class Codes: C12N 9/62 from Aspergillus
• CPC Class Codes: C12Y 302/01003 Glucan 1,4-alpha-glucosidase (3.2.1.3), i.e. glucoamylase
• CPC Class Codes: C12Y 302/01008 Endo-1,4-beta-xylanase (3.2.1.8)
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

The invention concerns a multi-enzyme product with glucoamylase, proteolytic and xylanase activities, characterized in that it consists of wheat bran fermented with an Aspergillus niger strain, said enzymatic glucoamylase, proteolytic and xylanase activities being present in the following minimum values: glucoamylase activity: at least 100 UG per gram of dry matter; proteolytic activity: at least 100 UP per gram of dry matter; xylanase activity: at least 100 UX per gram of dry matter, provided that at least one of the following conditions is satisfied:

the gluycoamylase activity is at least 750 UG per gram of dry matter

the xylanase is at least 300 UX per gram of dry matter. The invention is useful for producing ethanol or monogastric animal feed.

Claims

1. Multi-enzyme product exhibiting glucoamylase, proteolytic and xylanase activities, characterized in that it consists of wheat bran fermented with an Aspergillus niger strain, said enzymatic glucoamylase, proteolytic and xylanase activities being present at the following minimum values:

glucoamylase;

at least 100 GU per gram of dry matter,

proteolytic;

at least 100 PU per gram of dry matter,

xylanase;

at least 100 XU per gram of dry matter, provided that at least one of the following conditions is satisfied;

the glucoamylase activity is at least 750 GU per gram of dry matter,

the xylanase activity is at least 300 XU per gram of dry matter.

2. Product according to claim 1, characterized in that it exhibits a glucoamylase activity of at least 750 GU/g of dry matter.

3. Product according to claim 1, characterized in that it exhibits a glucoamylase activity of at least 1 500 GU/g of dry matter.

4. Product according to claim 1, characterized in that it exhibits a xylanase activity of at least 300 XU per gram of dry matter.

5. Product according to claim 1, characterized in that it exhibits a xylanase activity of at least 400 XU per gram of dry matter.

6. Product according to claim 1, characterized in that the Aspergillus niger strain is chosen from the NRRL 3112 strain, the ATCC 76061 strain and the strains obtained from said strains by selection or mutation.

7. Product according to claim 6, characterized in that the Aspergillus niger strain is the ATCC 76061 strain.

8. Method for producing the multi-enzyme product defined in claim 1, characterized in that it comprises the stages consisting in (a) taking wheat bran;

(b) moistening and heat-treating said bran so as to pasteurize it or sterilize it;

(c) inoculating the resulting wheat bran with an Aspergillus niger strain;

(d) the bran being in the form of a layer at least 10 cm thick, fermenting it in the solid state in a reactor which is aerated and stirred periodically for a period of 1 to 3 days, at a temperature of 28-38°

C., said bran being adjusted to an initial moisture content of 50 to 60 wt. % which is substantially maintained during fermentation, under aeration conditions appropriate for avoiding accumulation of carbon dioxide, which is harmful to the fermentation in the reactor, and a rise in temperature due to fermentation above the recommended range, until the fermentation product exhibits the following minimum enzyme activity values;

glucoamylase;

at least 100 GU per gram of dry matter,

proteolytic;

at least 100 PU per gram of dry matter,

xylanase;

at least 100 XU per gram of dry matter, provided that at least one of the following conditions is satisfied;

the glucoamylase activity is at least 750 GU per gram of dry matter,

the xylanase activity is at least 300 XU per gram of dry matter.

9. Method according to claim 8, characterized in that the Aspergillus niger strain is chosen from the NRRL 3112 strain, the ATCC 76061 strain and the strains obtained from said strains by selection or mutation.

10. Method according to claim 9, characterized in that the Aspergillus niger strain is the ATCC 76061 strain.

11. Method according to claim 8, characterized in that the moisture level of the bran is prevented from falling below 45% during fermentation.

12. Method according to claim 8, characterized in that it comprises the additional step consisting in freezing or drying the product obtained in stage d).

13. Use of a product according to claim 1 in the production of ethanol from wheat.

14. Use of a product according to claim 1 as a monogastric animal feed additive.