Fermentec, Av. Antonia Pizzinatto Sturion 1155, Piracicaba, SP, Brazil.
Appl Microbiol Biotechnol. 2011 Sep;91(5):1267-75. doi: 10.1007/s00253-011-3437-6. Epub 2011 Jul 7.
Bioethanol (fuel alcohol) has been produced by industrial alcoholic fermentation processes in Brazil since the beginning of the twentieth century. Currently, 432 mills and distilleries crush about 625 million tons of sugarcane per crop, producing about 27 billion liters of ethanol and 38.7 million tons of sugar. The production of bioethanol from sugarcane represents a major large-scale technology capable of producing biofuel efficiently and economically, providing viable substitutes to gasoline. The combination of immobilization of CO₂ by sugarcane crops by photosynthesis into biomass together with alcoholic fermentation of this biomass has allowed production of a clean and high-quality liquid fuel that contains 93% of the original energy found in sugar. Over the last 30 years, several innovations have been introduced to Brazilian alcohol distilleries resulting in the improvement of plant efficiency and economic competitiveness. Currently, the main scientific challenges are to develop new technologies for bioethanol production from first and second generation feedstocks that exhibit positive energy balances and appropriately meet environmental sustainability criteria. This review focuses on these aspects and provides special emphasis on the selection of new yeast strains, genetic breeding, and recombinant DNA technology, as applied to bioethanol production processes.
生物乙醇（燃料酒精）自 20 世纪初以来，通过巴西的工业酒精发酵工艺生产。目前，432 家工厂和酿酒厂每年大约要压榨 6.25 亿吨甘蔗，生产约 270 亿升乙醇和 3870 万吨糖。用甘蔗生产生物乙醇代表了一种大规模的主要技术，能够高效、经济地生产生物燃料，为汽油提供可行的替代品。甘蔗作物通过光合作用将二氧化碳固定在生物质中，然后对这种生物质进行酒精发酵，这一过程使得生产出清洁、高质量的液体燃料成为可能，这种燃料含有糖中 93%的原始能量。在过去的 30 年中，巴西的酒精厂引入了多项创新，提高了工厂的效率和经济竞争力。目前，主要的科学挑战是开发从第一代和第二代原料生产生物乙醇的新技术，这些技术具有积极的能量平衡，并适当满足环境可持续性标准。本文重点介绍了这些方面，并特别强调了用于生物乙醇生产过程的新型酵母菌株的选择、遗传育种和重组 DNA 技术。
