Optimization of Calvatia gigantea mycelia production from distillery wastewater

The focus of wastewater management has evolved from treatment technology into resource recovery, which enables one to minimize contaminants and to generate value‐added products. Calvatia gigantea is used not only as a source of food, but has also been used as a traditional Chinese medicine for thousands of years. In this study, the mycelial production of C. gigantea was studied under submerged fermentation conditions using non‐pretreated distilled wastewater from Chinese liquor production. The fermentation medium composition was optimized using response surface methodology involving a Box–Behnken design. Fermentation conditions were optimized using an orthogonal experimental design. The optimized medium composition was the non‐pretreated distilled wastewater of Chinese liquor supplemented with cornflour at 2.35 g/100 mL, (NH₄)₂SO₄ at 1.11 g/100 mL and CuSO₄ at 0.12 g/100 mL. The optimized fermentation conditions were a rotation speed of 150 rpm, an inoculum size of 10% (v/v), a fermentation temperature of 26 °C and a fermentation time 4.5 days. A maximum mycelial biomass yield of 2.75 g/100 mL was achieved using the optimized medium under the optimized conditions. Results from this study suggest that this is a feasible technology for the mycelial production of C. gigantea using the non‐pretreated distilled wastewater from Chinese liquor production. Copyright © 2015 The Institute of Brewing & Distilling