混合菌同步糖化共发酵造纸污泥产乙醇

The production of ethanol from paper mill sludge by simultaneous saccharification and fermentation of mixed bacteria

对酿酒酵母(Saccharomyces cerevisiae)与重组大肠杆菌KO11(Escherichia coli)混合菌同步糖化共发酵造纸污泥产乙醇进行了初步研究。在底物浓度为50g/L时,通过单因素实验和正交实验获得乙醇发酵的最佳条件:纤维素酶添加量25FPU/g底物,接种量为6%,酿酒酵母与重组大肠杆菌KO11接种比例为1∶1(细胞干重初始浓度分别为1.0g/L和0.3g/L左右)。发酵72h后,乙醇浓度为5.71g/L,产率达到0.114g乙醇/g污泥,达到理论值的42.3%。分别用酿酒酵母、KO11单菌种发酵与双菌株组合发酵对比结果表明,混合菌发酵效果明显优于单菌种发酵。

A primary study on mixed bacteria simultaneous saccharification and ethanol fermentation of paper mill sludge of saccharomyces cerevisiae and recombinant Escherichia coli KOll was carried out. The results show that when the substrate concentration is 50g/l, through the single factor and orthogonal experiments the best conditions of ethanol fermentation are got as follows： the amount of cellulase 25 FPU/g substrate, inoculation 6%, and the reorganization of the large intestine of saccharo myces cerevisiae 1：1 bacillus KOll inoculum （initial concentration of dry cell weight 1.0g/1 and 0.3g/ 1 or so）. After 72h fermentation, ethanol concentration reaches 5.71g/1, ethanol production rate reaches 0.114g/g sludge, reaching 42.3% of the theoretical value. The comparing result of saccharomyces cerevisiae, KOll single strain of bacteria and fermentation and double-contrast results showed the effect of mixture fermentation being better than single strain fermentation.