Enzymatic hydrolysis of cellulose

• US 3,990,945 A
• Filed: 09/18/1975
• Issued: 11/09/1976
• Est. Priority Date: 04/28/1975
• Status: Expired due to Term

• Current Assignee: BIO Research Center Co. Ltd.
• Original Assignee: BIO Research Center Co. Ltd.
• Inventors: Yata, Naoki, Huff, George F.
• Primary Examiner(s): Monacell, A. Louis
• Assistant Examiner(s): Wiseman, Thomas G.
• Application Number:
  US05/614,490
• Time in Patent Office: 418 Days
• Field of Search: 195/66 R, 195/65, 195/62, 195/33, 195/7, 195/11, 210/11, 210/2, 210/3
• US Class Current: 435/99
• CPC Class Codes: C12N 9/2434 acting on beta-1,4-glucosidic bonds
• CPC Class Codes: C12P 19/14 produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase , e.g. by cellulase, hemicellulase
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: Y10S 435/945 Trichoderma

Abstract

In the enzymatic hydrolysis of cellulose to obtain water-soluble sugars, the enzyme source is the aqueous culture mass obtained in an enzyme preparation step by cultivating in an aqueous nutrient medium in the presence of a cellulosic material a cellulolytic microorganism capable of elaborating a cellulolytic enzyme complex which can degrade native cellulose. No separation is made of any component of the culture mass. Such use of the culture mass as the enzyme source not only eliminates processing steps to separate the enzyme, but also results in increased hydrolysis rates and yields of the desired water-soluble sugars in the hydrolysis of cellulose.

Claims

1. In a process for the enzymatic hydrolysis of cellulose to obtain water-soluble sugars, wherein

a. an extracellular cellulolytic enzyme complex capable of degrading native celulose is prepared in an enzyme prparation step by cultivating in an aqueous nutrient medium in the presence of a cellulosic material a cellulolytic microorganism capable of elaborating said enzyme complex to obtain an aqueous culture mass, and

b. a cellulosic substrate is thereafter hydrolyzed in the presence of said enzyme complex under enzymatic hydrolysis conditions to obtain said sugars;

the improvement which comprises;

performing said enzyme preparation step and said hydrolysis step separately and utilizing in said hydrolysis step the aqueous culture mass of said enzyme preparation step or an aliquot thereof without separating any component thereof, thereby increasing the hydrolysis rate and the yield of water-soluble sugars in said hydrolysis step, and obtaining said sugars from said process.

2. The process of claim 1, wherein the cellulolytic microorganism is Trichoderma viride.

3. The process of claim 1, wherein the cellulosic material of the enzyme preparation step and the cellulosic substrate of the hydrolysis step are derived from waste cellulose.