Abstract

The shortage of fossil fuels is actually a major economic issue in the context of increasing energy demand. Renewable energies are thus gaining in importance. For instance, microalgae-based fuels are viewed as an alternative. Microalgae are microscopic unicellular plants, which typically grow in marine and freshwater environments. They are fast growing, have high photosynthetic efficiency, and have relatively small land requirement and water consumption in comparison with conventional land crops biofuels. Nonetheless, selling biofuels is still limited by high cost. Here, we review biofuel production from microalgae, including cultivation, harvesting, drying, extraction and conversion of microalgal lipids. Cost issues may be solved by upstream and downstream measures: (1) upstream measures, in which highly productive strains are obtained by strain selection, genetic engineering and metabolic engineering, and (2) downstream measures, in which high biofuels yields are obtained by enhancing the cellular lipid content and by advanced conversion of microalgal biomass to biofuels. Maximum biomass and high biofuels production can be achieved by two-stage culture strategies, which is a win–win approach because it solves the conflicts between cell growth and biomass accumulation.

中文翻译：

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微藻生产生物燃料的评论

摘要

在能源需求不断增加的情况下，化石燃料的短缺实际上是一个主要的经济问题。因此，可再生能源变得越来越重要。例如，微藻类燃料被视为替代品。微藻是微观的单细胞植物，通常在海洋和淡水环境中生长。与常规的陆地作物生物燃料相比，它们生长迅速，光合效率高，土地需求和耗水量相对较小。尽管如此，销售生物燃料仍然受到高成本的限制。在这里，我们回顾了微藻的生物燃料生产，包括微藻脂质的培养，收获，干燥，提取和转化。成本问题可以通过上游和下游措施来解决：（1）上游措施，其中通过菌株选择，基因工程和代谢工程获得高产菌株，以及（2）下游措施，其中通过提高细胞脂质含量和通过将微藻类生物质提前转化为生物燃料获得高生物燃料产量。两步培养策略可实现最大的生物量和高生物燃料产量，这是一种双赢的方法，因为它解决了细胞生长与生物量积累之间的矛盾。