Powerful tools for productivity improvements in microalgal production

• Published in: Renewable & sustainable energy reviews 2021-12, Vol.152, p.111609, Article 111609
• Main Authors: Sun, Han, Wu, Tao, Chen, Stephenie Hiu Yuet, Ren, Yuanyuan, Yang, Shufang, Huang, Junchao, Mou, Haijin, Chen, Feng
• Format: Article
• Language: English
• Subjects: Genetic tool; Kinetic model; Lipid biosynthesis; Metabolic flux analysis; Microalgal production; Productivity improvement
• ISSN: 1364-0321; 1879-0690
• DOI: 10.1016/j.rser.2021.111609

Technology for microalgae cultivation has potential to maximize biomass generation to production process and economic viability of microalgal production. Powerful tools that increase the production and value of microalgae are therefore of great significance. In this review, valid approaches involved in strain screening, microalgal cultivation, cell harvesting and disruption are discussed with regards to productivity improvements and energy efficiency. Particularly, current research in kinetic models, metabolic flux analysis and genetic tools are considered. Kinetic models of nutrient, light, temperature and cell quota to increase the biomass concentration and targeted products are discussed. Metabolic flux analysis, especially GC–MS-based 13C-metabolic flux analysis is discussed to describe how the central carbon flux to targeted products can be precisely and rapidly engineered. This approach is exemplified by Chromochloris zofingiensis under batch and fed-batch cultures. Molecular approaches including gene silencing methods and CRISPR–Cas9 are also discussed as these provide powerful tools for enhanced production of biomass and associated lipids and carotenoids. Finally, the huge potential of combined applications of the described tools are discussed. A better understanding of cell behavior in response to these tools will provide the means to improve microalgal production at a competitive cost. •Economic viability limits microalgal production due to unsatisfied productivity.•Valid approaches to improve each step in production are reviewed and discussed.•Tools for productivity improvements of microalgae are reviewed comprehensively.•Major molecular approaches for enhanced lipid production are summarized.