采用响应面分析方法,对红曲霉菌株(Monascus ruber GM A4)固态发酵产Monacolin K的工艺条件进行优化研究,提高产Monacolin K的浓度,运用单因子实验筛选出可溶性淀粉和酵母粉为最适碳源和氮源,确定发酵产Monacolin K的最佳培养时间为20天,初始含水量为40%以及添加前体乙酸钠浓度为1.2%,通过全因子实验,对影响产Monacolin K的4个重要因素进行评估并筛选出具有显著效应的2个因子:初始含水量、乙酸钠.通过最陡爬坡逼近以上2个因子的最大响应区域后,采用Central Composite Design(CCD)响应面分析法,确定产Monacolin K最佳工艺条件为:可溶性淀粉40g/L,酵母粉30g/L,乙酸钠14.6g/L,初始含水量51.2%,32℃培养3天,再26℃培养17天.在此条件下,Monacolin K产量达到15.49mg/g,比优化前条件:葡萄糖30g/L,蛋白胨20g/L,酵母粉20g/L,乙酸钠12g/L,初始含水量40%所得到的Monacolin K浓度11.03mg/g提高了40.4%.%Response Surface Methodology (RSM) was used to optimize the solid -state fermentation conditions to enhance the production of Monacolin K using Monascus Ruber GM A4. In single factor experiment, soluble starch and yeast extract were screened out as the most suitable carbon and nitrogen sources, the most suitable cultured time was 20 days, the initial moisture content was 40％ and the addition of CH3COONa was 1.2. The full factorial design was used to evaluate four important factors related to Monacolin K production and two factors had statistically significant effects:initial moisture content and CH3COONa. Steepest ascent procedures were applied to define optimal response region for these two factors, finally the optimal factor concentrations were determined by RSM analysis. The results showed that soluble starch 40g/L, yeast extract 30g/L, CH3 COONa 14. 6g/L and initial moisture content 51.2％, cultured for three days at 32℃, then 17 days at 26℃ was the most suitable fermentation conditions for Monacolin K production.Under the above condition, the productivity of Monacolin K increased from 11.03mg/g to 15.49mg/g. Before the optimization, the fermentation condition were: glucose 30g/L, peptone 20g/L, yeast extract 20g/L, CH3COONa 12g/L and initial moisture content 40％.
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