Catalytic Properties of Amylolytic Enzymes Produced by Gongronella butleri Using Agroindustrial Residues on Solid-State Fermentation

Abstract

Amylases catalyze the hydrolysis of starch, a vegetable polysaccharide abundant in nature. These enzymes can be utilized in the production of syrups, alcohol, detergent, pharmaceutical products, and animal feed formulations. The aim of this study was to optimize the production of amylases by the filamentous fungus Gongronella butleri by solid-state fermentation and to evaluate the catalytic properties of the obtained enzymatic extract. The highest amylase production, 63.25 U g−1 (or 6.32 U mL−1), was obtained by culturing the fungus in wheat bran with 55% of initial moisture, cultivated for 96 h at 25°C. The enzyme presented optimum activity at pH 5.0 and 55°C. The amylase produced was stable in a wide pH range (3.5–9.5) and maintained its catalytic activity for 1 h at 40°C. Furthermore, the enzymatic extract hydrolyzed starches from different vegetable sources, presenting predominant dextrinizing activity for all substrates evaluated. However, the presence of glucose was observed in a higher concentration during hydrolysis of corn starch, indicating the synergistic action of endo- and exoamylases, which enables the application of this enzymatic extract to produce syrups from different starch sources.

Millet Cobs: A Source of Microbial Enzymes

“…Thus, temperature contributes to the factor responsible for the secretion of amylase. Cavalheiro et al documented that high enzymatic activity for amylase production by Gongronella butleri was between pH ranges of 4.0-5.5 [99]. Nwagu and Okolo reported that amylase produced by A. fumigatus maintained 94% of its activity at pH 4.5-6.5 for 24 hours [99].…”

“…Cavalheiro et al documented that high enzymatic activity for amylase production by Gongronella butleri was between pH ranges of 4.0-5.5 [99]. Nwagu and Okolo reported that amylase produced by A. fumigatus maintained 94% of its activity at pH 4.5-6.5 for 24 hours [99]. de-Souza and Magalhães reported that A. niger has important hydrolytic capacities in amylase production and its tolerance of acidity (pH<3) could be a factor in the production of amylase by different Aspergillus spp isolated [100].…”

β-glucosidase from thermophilic fungus Thermoascus crustaceus: production and industrial potential

“…Our research group has been working on the description of new biocatalysts from enzymeproducing filamentous fungi isolated from the Midwest region of Brazil, with appreciable biotechnological characteristics such as low production cost, high structural stability, and broad industrial applicability (Cavalheiro et al 2017, Costa et al 2019, Garcia et al 2015, Morais et al 2018). Among the strains recently isolated by our team, the thermophilic filamentous fungus Thermoascus crustaceus stood out for the production of the enzyme β-glucosidase.…”