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Multiple models have been developed in the field to simulate growth and product accumulation of microalgal cultures. These models heavily depend on the accurate estimation of growth parameters. In this paper growth parameters are presented for three industrially relevant microalgae species: Nannochloropsis sp., Neochloris oleoabundans, and Picochlorum sp. (BPE23). Dedicated growth experiments were done in photobioreactors to determine the maximal biomass yield on light and maintenance rate, while oxygen evolution experiments were performed to estimate the maximal specific growth rate. Picochlorum sp. exhibited the highest specific growth rate of 4.98 ± 0.24 day−1 and the lowest specific maintenance rate of 0.079 day−1, whereas N. oleoabundans showed the highest biomass yield on light of 1.78 gx·molph−1. The measured growth parameters were used in a simple kinetic growth model for verification. When simulating growth under light conditions as found at Bonaire (12 °N, 68° W), Picochlorum sp. displayed the highest areal biomass productivity of 32.2 g.m−2·day−1 and photosynthetic efficiency of 2.8%. The presented growth parameters show to be accurate compared to experimental data and can be used for model calibration by scientists and industrial communities in the field.

In this feature, leading researchers in the field of microbial biotechnology speculate on the technical and conceptual developments that will drive innovative research and open new vistas over the next few years

The carbon footprint caused by unsustainable development and its environmental and economic impact has become a major concern in the past few decades. Photosynthetic microbes such as microalgae and cyanobacteria are capable of accumulating value-added compounds from carbon dioxide, and have been regarded as environmentally friendly alternatives to reduce theusage of fossil fuels, thereby contributing to reducing the carbon footprint. This light-driven generation of green chemicals and biofuels has triggered the research for metabolic engineering of these photosynthetic microbes. CRISPR-Cas systems are successfully implemented across a wide range of prokaryotic and eukaryotic species for efficient genome editing. However, the inception of this genome editing tool in microalgal and cyanobacterial species took off rather slowly due to various complications. In this review, we elaborate on the established CRISPR-Cas based genome editing in various microalgal and cyanobacterial species. The complications associated with CRISPR-Cas based genome editing in these species are addressed along with possible strategies to overcome these issues. It is anticipated that in the near future this will result in improving and expanding the microalgal and cyanobacterial genome engineering toolbox.

Microalgae are a promising feedstock for sustaineble production of biofuela due to their unique capacity to reach high lipid productivities. Although the promises are there, production costs and energy requirements are high and the technology is still ammature for the production of bulk products. It is an enormous challange to transfer technology so far used for production of high-value niche products to a technology to be used at industrial scale for commodities. A new mind-set is needed and knowledge needs to be gained in different scientific disciplines, intergrated, applied, and demontrated in an industrial context. Biofuels from microalgae can only become realistic if the cost of production of algae is reduced, if the produntivity of lipids in microalgae is maximized, and if besides lipids, other compounds are validated for applications for food, feed, chemistry, and materials using a microalgal biorefinery.