关键词: 小香蕈, 液体发酵, 培养基优化, 响应面法, 菌丝生长速度, 菌丝生物量

Abstract: To optimize the liquid spawn fermentation medium formula of Lentinula edodes，with PDA and CPDA media as the control groups，single⁃factor experiments were carried out at a rotating speed of 150 r/min.Five temperature gradients（10，15，20，25，30 ℃），five carbon sources（fructose，maltose，dextrin，brown sugar and white granulated sugar），five nitrogen sources（soybean flour，bran，peptone，yeast powder and NH4Cl），and five inorganic salts（MgSO₄，KH₂PO₄，NaCl，CaCl₂，MgCl₂）were set to screen the factor levels that promoted the fastest mycelial growth of Lentinula edodes.On this basis，concentration gradient experiments were conducted on the screened optimal carbon source，nitrogen source and inorganic salt to determine their optimal addition amounts.Furthermore，a response surface model of fermentation parameters was constructed for further optimization tests.The results of single⁃factor experiments showed that temperature，carbon source，nitrogen source and inorganic salt kinds and their concentration all significantly affected the mycelial biomass of Lentinula edodes，and the mycelial biomass increased first and then decreased with the rise of each factor level.The optimal culture temperature was 25 ℃，with a mycelial biomass of 2.733 g/L.Dextrin was selected as the optimal carbon source，and the maximum mycelial biomass of 6.156 g/L was obtained at the dextrin concentration of 30 g/L.Soybean meal was the optimal nitrogen source，with a peak mycelial biomass of 11.133 g/L at 20 g/L. CaCl ₂ was the best inorganic salt，with the maximum mycelial biomass of 5.044 g/L at the concentration of 3 g/L. Excessively high levels of each factor would inhibit mycelial growth and reduce mycelial biomass.The optimal medium formula for liquid spawn fermentation of Lentinula edodes obtained by response surface methodology was as follows：dextrin 28 g/L，soybean meal 22 g/L，and CaCl₂ 3 g/L. Under this formula，the measured mycelial biomass was 14.222 g/L，which was basically consistent with the model’s predicted value of 14.202 g/L，indicating that the optimized medium formula was effective and feasible.

Key words: Lentinula edodes, Liquid fermentation, Medium optimization, Response surface methodology, Mycelial growth rate, Mycelial biomass