紫色红曲霉FBKL3.0018液态发酵产红曲色素条件的优化研究

Optimization of submerged fermentation conditions of Monascus purpureus FBKL3.0018 for monascus pigment production

以分离自贵州某浓香型酒厂中温大曲的紫色红曲霉(Monascus purpureus)FBKL3.0018为研究对象,以发酵液中红曲色素色价为考察指标,对紫色红曲霉FBKL3.0018产红曲色素的发酵培养基配方进行优化。考察了碳源、氮源、无机盐、生长因子及初始p H值对红曲色素生产的影响,选取对红曲色素生产影响较显著的蛋白胨、Fe SO_4和初始p H进行响应面优化试验。得到最佳培养基配方为:葡萄糖60 g/L、蛋白胨26 g/L、Fe SO_40.9 g/L、L-谷氨酸2 g/L和初始p H 4.5。在此优化条件下,红曲色素色价为105.22 U/mL,比优化之前(33.62 U/mL)提高了3.13倍。同时,通过验证试验,实际值105.22 U/mL与预测值108.82 U/mL相对误差为0.97%,说明所建立的回归模型可靠。

Using Monascus purpureus FBKL3.0018 isolated from medium temperature Daqu of Guizhou Luzhou-flavor distillery as research object, the monascus pigment color value of fermentation broth as investigation index, the medium formula of M. purpureus FBKL3.0018 fermentation for pigment production was optimized. The effects of carbon source, nitrogen source, inorganic salt, growth factors and initial pH on the production of monascus pigment were investigated, and the factors （peptone, FeSO4 and initial pH） significantly affecting the pigment production were optimized by response surface methodology. Results showed that the optimal medium formula was glucose 60 g/L, peptone 26 g/L, FeSO4 0.9 g/L, L-Glu 2 g/L and initial pH 4.5. Under the optimized medium, the color value of the monascus pigment was 105.22 U/ml, which was 3.13 times that of before optimization （33.62 U/ml）. At the same time, through validation experiments, the relative error between the actual value （105.22 U/ml） and the predicted value （108.82 U/ml） was 0.97%, which indicated that the established regression model was reliable.