Production of amylases by Aspergillus tamarii

Abstract

A strain of Aspergillus tamarii, a filamentous fungus isolated from soil, was able to produce both α-amylase and glucoamylase activities in mineral media supplemented with 1% (w/v) starch or maltose as the carbon source. Static cultivation led to significantly higher yields than those obtained using shaking culture. The production of amylases was tolerant to a wide range of initial culture pH values (from 4 to 10) and temperature (from 25 to 42 o C). Two amylases, one α-amylase and one glucoamylase, were separated by ion exchange chromatography. Both partially purified enzymes had optimal activities at pH values between 4.5 and 6.0 and were stable under acid conditions (pH 4.0-7.0). The enzymes exhibited optimal activities at temperatures between 50 o and 60 o C and were stable for more than ten hours at 55 o C.

Production of Raw Starch-Saccharifying Thermostable and Neutral Glucoamylase by the Thermophilic Mold Thermomucor indicae-seudaticae in Submerged Fermentation

“…Glucoamylase production was recorded in almost all carbon sources (starch, glucose, maltose, fructose, lactose, mannose, galactose, cellobiose, raffinose, arabinose, inulin, sorbitol, mannitol, inositol, and sucrose) tested. The synthesis of glucoamylase in this mold is constitutive, as reported in Aspergillus tamarii [23].…”

A thermostable maltose‐tolerant α‐amylase from Aspergillus tamarii

“…A strain of Aspergillus tamarii isolated from soil during a screening program for amylaseproducing microorganisms has been described as able to produce both liquefying (α-amylase) and saccharifying (glucoamylase) activities. Its α-amylase was responsible by more than of 70% of total amylolytic activity found in the culture filtrates (MOREIRA et al 1999). In this work, we described the purification and some physicochemical properties of the α-amylase from A. tamarii that showed thermostability and remarkable insensitivity to end product inhibition, glucose and maltose.…”

Isolation and Characterization of Amylase Producing Yeasts and Improvement of Amylase Production

“…Below and above this pH, amylase production decreased gradually. Moreira et al [25] found that the amylase production by Aspergillus tamarii was higher at pH 6 while Nahas and Waldemarin [26] observed the maximum amylase production by Aspergillus ochraceus at initial pH 5.0. Also, the result is in agreement with the result of Hostinova [27], who found that the optimal pH for glucoamylase and α-amylase of S. fibuligera was 5.0-6.2.…”