中文摘要：

研究了红曲霉产多糖的液态发酵条件,得出优化后的培养基组成为：蔗糖45 g/L,酵母粉4.5 g/L,KH2PO4·3H2O 3.5 g/L,MgSO4·7H2O 0.85 g/L.通过单因素实验和正交试验,得到红曲霉N产多糖的优化发酵工艺条件为：种龄30 h,接种量7.5%,发酵培养基初始pH 5.75,装液量162.5mL/1 000 mL三角瓶,发酵时间84 h.在此条件下,红曲霉液态发酵的多糖质量浓度达999.8 mg/L,比优化前的684.2 mg/L提高46.1%。

英文摘要：

The liquid state fermentation conditions of polysaccharide by Monascus sp. were investigated. The optimized culture medium was as follows, sucrose 45 g/L, yeast extract powder 4.5 g/L, KH2PO4·3H2O 3.5 g/L, MgSO4·7H2O 0. 85 g/L. The fermentation conditions were optimized by single factor ex- periment and orthogonal test. The optimal fermentation conditions were as follows, seed culture age of 30 h, inoculation volume of 7.5% , initial pH of 5.75, liquid medium volume of 162.5 mL in 1 000 mL conical flask, and the fermentation lasted for 84 h. The highest yield of polysaccharide could be up to 999.8 mg/L, which was 46.1% higher than that of original yield of 684.2 mg/L.