纤维燃料乙醇生产中木糖发酵的研究进展

Progress of Xylosic Fermentation of Lignocellulosic Materials for Bioethanol Production

木糖是木质纤维质水解产物中含量仅次于葡萄糖的单糖,由半纤维素水解生成。研究表明,将木质纤维素原料中的木糖发酵生成乙醇,可提高纤维燃料乙醇的转化效率25%左右。天然菌种在发酵过程中具有副产物多、乙醇得率低、易污染、耐乙醇能力差等缺点,难以工业化应用。近年来许多研究者构建了可以高效代谢五碳糖和六碳糖的基因重组菌。虽然这些重组菌株在木糖转化酒精方面均显示出良好的应用前景,但仍存在诸多问题。本文介绍了近年来代谢工程改造微生物菌种发酵木糖生产酒精的研究进展,以期为利用农作物秸秆转化燃料乙醇研究提供参考依据。

Xylose is a monosaccharide from the hydrolysis of hemieellulose of lignocellulosie materials,it is second only to glucose levels. The fermentation of xylose from lignocellulosie materials can increase the production of ethanol about 25%. There are many microorganisms in nature, but currently there is no natural microorganisms discovered for transforming the renewable lignocellulosie materials effieiently. For the last two decades, many improvements have been done in the metabolic engineering of yeasts and bacterium including Z. mobilis and E. coli for the fermentation of xylose to selectively produce ethanol through introducing either xylose metabolic genes or ethanol production genes into the above hosts and a serial of recombinant strains have been constructed. Although some of them have shown great promise for industrial exploitation, there are still a lot of problems existing. The review tries to efforts for developing microbial strains to ferment xylose to ethanol efficiently outline some major through metabolic engineering, offering useful reference for transforming lignocellulosic biomass into bioethanol.