Production of amylases from Coprinus comatus under submerged culture using wheat-milling by-products: Optimization, kinetic parameters, partial purification and characterization

• Published in: Biocatalysis and agricultural biotechnology Vol. 17; pp. 82 - 92
• Main Authors: Frantz, Suélen Caroline, Paludo, Luana Cristina, Stutz, Herta, Spier, Michele Rigon
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2019
• Subjects: Bioprocess; By-products; Glucoamylase; Kinetic parameters; Macromycetes; α-amylase; Glucoamylase; α-amylase; Kinetic parameters; Macromycetes; By-products; Bioprocess
• ISSN: 1878-8181; 1878-8181
• DOI: 10.1016/j.bcab.2018.11.004

Amylases are enzymes that hydrolyze starch, and are mostly produced from microbial sources. This study aimed to evaluate the potential of utilization of wheat milling by-products for the production of amylases by a macromycete strain, Coprinus comatus, recently discovered as a potential producer of amylases under submerged culture. The best results of enzymatic activity (6.07 U mL−1 for α-amylase and 0.64 U mL−1 for glucoamylases) were obtained in a medium containing 10 g L−1 of low-grade flour (LGF) as substrate. The composition of the culture medium was optimized by experimental designs. The enzymatic activities obtained in the optimized culture medium (105 g L−1 LGF, 3.76 g L−1 urea and 7.52 g L−1 K2HPO4) were 59.40 ± 0.56 U mL−1 and 12.65 ± 0.09 U mL−1 for α-amylases and glucoamylases, respectively, representing an increase of 9.78 and 19.77 fold in the initial enzymatic production. High productivity (0.59 U mL−1 h−1 for α-amylase and 0.11 U mL−1 h−1 for glucoamylase) and product formation yield on substrate consumed (814.28 U gds−1 for α-amylase and 231.24 U gds−1 for glucoamylase) were obtained in the kinetic study. These results show that the use of LGF medium represents a low-cost alternative for the production of amylases by the species studied. The characterization of the partially purified enzymes showed optimal activity at temperature of 50 °C and pH 5.0, in addition to the independence of the calcium ion, a desirable characteristic for amylases produced for industrial application. [Display omitted] •Four by-products of wheat processing were tested for amylases production.•The utilization of Low-Grade Flour substrate for amylases production is reported for the first time.•Increase of 9.78 fold in α-amylase production and 19.77 fold in glucoamylase production with the optimization.•High productivity was obtained in the kinetic study of the optimized bioprocess.•The amylases from C. comatus showed biochemical characteristics desired for several industrial processes.