Sues Anna, Millati Ria, Edebo Lars, Taherzadeh Mohammad J
Department of Chemical Engineering and Environmental Science, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
FEMS Yeast Res. 2005 Apr;5(6-7):669-76. doi: 10.1016/j.femsyr.2004.10.013.
Consumption of hexoses and pentoses and production of ethanol by Mucor indicus were investigated in both synthetic media and dilute-acid hydrolyzates. The fungus was able to grow in a poor medium containing only carbon, nitrogen, phosphate, potassium, and magnesium sources. However, the cultivation took more than a week and the ethanol yield was only 0.2 gg(-1). Enrichment of the medium by addition of trace metals, particularly zinc and yeast extract, improved the growth rate and yield, such that the cultivation was completed in less than 24 h and the ethanol and biomass yields were increased to 0.40 and 0.20 gg(-1), respectively. The fungus was able to assimilate glucose, galactose, mannose, and xylose, and produced ethanol with yields of 0.40, 0.34, 0.39, and 0.18 gg(-1), respectively. However, arabinose was poorly consumed and no formation of ethanol was detected. Glycerol was the major by-product in the cultivation on the hexoses, while formation of glycerol and xylitol were detected in the cultivation of the fungus on xylose. The fungus was able to take up the sugars present in dilute-acid hydrolyzate as well as the inhibitors, acetic acid, furfural, and hydroxymethyl furfural. M. indicus was able to grow under anaerobic conditions when glucose was the sole carbon source, but not on xylose or the hydrolyzate. The yield of ethanol in anaerobic cultivation on glucose was 0.46 g g(-1).
在合成培养基和稀酸水解液中研究了印度毛霉对己糖和戊糖的消耗以及乙醇的产生。该真菌能够在仅含有碳、氮、磷、钾和镁源的贫培养基中生长。然而，培养需要一周多的时间，乙醇产量仅为0.2 gg(-1)。通过添加微量金属，特别是锌和酵母提取物来富集培养基，提高了生长速率和产量，使得培养在不到24小时内完成，乙醇和生物量产量分别提高到0.40和0.20 gg(-1)。该真菌能够同化葡萄糖、半乳糖、甘露糖和木糖，产生乙醇的产量分别为0.40、0.34、0.39和0.18 gg(-1)。然而，阿拉伯糖的消耗很少，未检测到乙醇的形成。甘油是在己糖培养中的主要副产物，而在木糖培养中检测到甘油和木糖醇的形成。该真菌能够吸收稀酸水解液中存在的糖以及抑制剂乙酸、糠醛和羟甲基糠醛。当葡萄糖是唯一碳源时，印度毛霉能够在厌氧条件下生长，但在木糖或水解液上不能生长。在葡萄糖上进行厌氧培养时乙醇产量为0.46 g g(-1)。
