Department of Industrial Microbiology, Maria Curie-Sklodowska University, Lublin, Poland.
Pol J Microbiol. 2011;60(1):51-8.
A total of 24 yeast strains were tested for their capacity to produce ethanol, and of these, 8 were characterized by the best ethanol yields (73.11-8 1.78%). The most active mutant Saccharomyce s cerevisiae ER-A, resistant to ethanol stress, was characterized by high resistance to acidic (pH 1.0 and 2.0), oxidative (1 and 2% of H2O2), and high temperature (45 and 52 degrees C) stresses. During cultivation under all stress conditions, the mutants showed a considerably increased viability ranging widely from about 1.04 to 3.94-fold in comparison with the parent strain S. cerevisiae ER. At an initial sucrose concentration of 150 g/l in basal medium A containing yeast extract and mineral salts, at 300C and within 72 h, the most active strain, S. cerevisiae ER-A, reached an ethanol concentration of 80 g/1, ethanol productivity of 1.1 g/Il/h, and an ethanol yield (% of theoretical) of 99.13. Those values were significantly higher in comparison with parent strain (ethanol concentration 71 g/1 and productivity of 0,99 g/l/h). The present study seems to confirm the high effectiveness of selection of ethanol-resistant yeast strains by adaptation to high ethanol concentrations, for increased ethanol production.
总共测试了 24 株酵母菌株的乙醇生产能力，其中 8 株具有最佳的乙醇产量（73.11-81.78%）。最活跃的突变体酿酒酵母 ER-A 具有耐乙醇应激的特性，其特点是对酸性（pH 值为 1.0 和 2.0）、氧化（1%和 2%的 H2O2）和高温（45 和 52 摄氏度）应激具有很高的抵抗力。在所有应激条件下培养时，与亲本菌株 S. cerevisiae ER 相比，突变体的存活率大大提高，范围从约 1.04 倍到 3.94 倍不等。在含有酵母提取物和无机盐的基础培养基 A 中初始蔗糖浓度为 150 g/l、30°C 下培养 72 小时时，最活跃的菌株 S. cerevisiae ER-A 达到 80 g/1 的乙醇浓度、1.1 g/Il/h 的乙醇生产率和 99.13%的乙醇产率（理论值的百分比）。与亲本菌株（乙醇浓度为 71 g/1 和生产率为 0.99 g/l/h）相比，这些值显著提高。本研究似乎证实了通过适应高乙醇浓度选择耐乙醇酵母菌株以提高乙醇产量的高效性。
