Nutritional requirements for the mycelial biomass and exopolymer production by Hericium erinaceus CZ-2.

摘要

In this work, the effects of medium composition and fermentation parameters on the simultaneous production of mycelial biomass and exopolymer by medicinal mushroom H. erinaceus CZ-2 were investigated in shake flask cultures using one-factor-at-a-time method and orthogonal array design. Results showed that the most suitable carbon, nitrogen, mineral sources, and cofactors for the mycelial biomass and exopolymer production were corn flour combined with 1% glucose, yeast extract, KH< sub>2PO< sub>4, and corn steep liquor. The intuitive analysis of orthogonal array design results indicated that the effects of nutritional requirement on the mycelial growth of H. erinaceus CZ-2 were in regular sequence of corn flour combined with 1% glucose>yeast extract>corn steep liquor>KH< sub>2PO< sub>4, and those on exopolymer production were in the order of corn flour combined with glucose>KH< sub>2PO< sub>4corn steep liquor. The maximal yield of mycelial biomass (16.07 g/litre) was obtained when the composition of the culture medium was (in g/litre) corn flour 30, glucose 10, yeast extract 3, KH< sub>2PO< sub>4 1, CaCO< sub>3 0.5, and 15 ml/litre of corn steep liquor. Meanwhile, the maximal exopolymer yield (1.314 g/litre) was achieved when the composition of medium was (in g/litre) corn flour 30, glucose 10, yeast extract 5, KH< sub>2PO< sub>4 3, CaCO< sub>3 0.5, and 15 ml/litre of corn steep liquor. In the 15-litre scale-up fermentation, the maximum mycelial biomass yield of 20.50 g/litre was achieved using the optimized medium.