US 9,765,374 B2 · Method of using α-amylase from Aspergillus fumigatus and isoamylase for saccharification

Abstract

A fungal alpha-amylase is provided from Aspergillus fumigatus (AfAmyl). AfAmyl has an optimal pH of 3.5 and is operable at 30-75 degrees C., allowing the enzyme to be used in combination with a glucoamylase and an isoamylase in a saccharification reaction. This obviates the necessity of running a saccharification reaction as a batch process, where the pH and temperature must be readjusted for optimal use of the alpha-amylase or glucoamylase. AfAmyl also catalyzes the saccharification of starch substrates to an oligosaccharide composition significantly enriched in DP2 and (DPI+DP2) compared to the products of saccharification catalyzed by an alpha-amylase from Aspergillus kawachii. This facilitates the utilization of the oligosaccharide composition by a fermenting organism in a simultaneous saccharification and fermentation process, for example.

Claims19

Dependent claims

A method of saccharifying a composition comprising starch to produce a composition comprising glucose, wherein said method comprises:

(i) contacting said composition comprising starch with an isoamylase and an isolated AfAmyl or variant thereof having α-amylase activity comprising an amino acid sequence with at least 80% amino acid sequence identity to (a) residues 24-630 of SEQ ID NO:1 or (b) residues 24-502 of SEQ ID NO:1;
and
(ii) saccharifying said composition comprising starch to produce said composition comprising glucose;
wherein said isoamylase and said isolated AfAmyl or variant thereof catalyze the saccharification of the starch composition to glucose wherein the AfAmyl or variant thereof is dosed at 17%-50% the dose of AkAA, to reduce the same quantity of residual starch under the same conditions, and wherein the saccharification results in 2%-11% less residual starch compared to a saccharification carried out by said isoamylase and AkAA under the same conditions.

1 more element

Dependencies are inferred from the claim text.

Method of using α-amylase from Aspergillus fumigatus and isoamylase for saccharification

Life of this patent

Method of using α-amylase from Aspergillus fumigatus and isoamylase for saccharification

Life of this patent

Abstract

Claims19