微藻异养高密度培养研究进展与发展趋势*

微藻细胞可以积累大量油脂、蛋白质、多糖、色素、不饱和脂肪酸等物质,在能源、食品、饵料、保健品及药品等行业有巨大的应用价值。然而,微藻在传统光自养模式下很难实现高密度培养来大量生产这些重要的物质,进而限制了微藻的实际应用。相反,微藻在异养模式下生长速度快、生物质浓度高,可以短时间内获得大量微藻生物质。因此,异养高密度培养微藻具备大规模、高效率培养微藻生产目标产物的巨大潜力。阐述微藻异养培养的优缺点及相应技术难点的解决思路、影响微藻异养生长及目标产物积累的主要营养因子和环境因子、微藻异养高密度培养的方式及微藻异养高密度培养的当前发展水平。结合文献报道分析微藻异养高密度培养的四个具有极大发展潜力的发展方向,以期更好地利用异养模式来高效率、低成本培养微藻生产大量目标产物,满足上述多个行业对微藻原材料的巨大需求,从而加速微藻产业的发展。

Research Progress and Future Direction on High-cell-density Heterotrophic Cultivation of Microalgae

Microalgae are sources of many important chemicals, such as lipids, proteins, polysaccharides, pigments and polyunsaturated fatty acids, which have a broad range of applications in biofuels, food, feed, nutraceutical, and pharmaceutical industries. However, the low production of microalgal biomass under photoautotrophic cultivation has limited its applications. In contrast, microalgae can grow fast and achieve ultrahigh cell densities under heterotrophic cultivation. These characteristics make heterotrophic cultivation have a promising potential for industrial production of microalgae-based products. This review aims to provide an overview of the advantages and disadvantages in microalgal heterotrophic cultivation, and the factors and strategies affecting microalgal cell growth as well as the current production of several microalgae under high-cell-density heterotrophic cultivation. The path forward for further economical and efficient production of microalgal target compounds under high-cell density heterotrophic culture with respect to four different opportunities is also discussed, which will in turn meet the huge demand of microalgal feedstocks in the above industries and accelerate the development of microalgae industry.