Wheat Milling by-Products: an Alternative to Produce Amylolytic Enzymes by Mushrooms Strains

Abstract

The goal of this study was to evaluate the α-amylases production by basidiomycetes in submerged cultivation (SmC), using wheat milling by-products as substrate. Enzymatic activity was evaluated to select the best strain, the ideal concentration, the by-product and the influence of supplementation in the culture medium. The best producer was chosen among three strains, Ganoderma applanatum (MR-56), Schizophyllum commune (MR-01), and Ganoderma stipitatum . All of them were cultivated under the same conditions. MR-56 was selected for an initial screening activity of 5.10±0.31 U/mL in 192h. The Ganoderma applanatum strain was cultured in a medium with various starch concentrations to determine which concentration resulted in the highest α-amylase activity. After 120h of cultivation, activity in the medium containing 4.5% (w/v) had increased from 0.40±0.03 U/mL to 20.70±0.9 U/mL. Subsequently, the wheat milling by-products [Glue Flour (GF), Clean-Out Flour (CF4) Flour, and Low-grade Flour (LGF)] were evaluated in aqueous suspension with and without nutritional supplementation. It was shown that GF and LGF are potential starch sources which do not require nutritional supplementation, exhibiting increases in αamylase activity of 31.79 U/mL and 30.98 U/mL, respectively. This is the first report involving the application of Ganoderma applanatum in SmC for α-amylase production using synthetic and wheat milling by-products. The results also demonstrated that wheat milling by-products may also be used without supplementation for HIGHLIGHTS• One of the first works on the amylase production by Ganoderma applanatum;• Production of α-amylase in the wheat milling by-product without supplementation;• This strain showed potential to produce amylase in several wheat milling by-products;• Amylase production costs 42-fold less with by-product than synthetic medium;•