High-throughput screen for high performance microalgae strain selection and integrated media design

Microalgae provide a powerful biotechnology platform for the production of renewable fuels, animal-feeds and high-value products. Here, a new high-throughput nutrient optimisation screen was used to maximise photoautotrophic growth rates for 100 newly bio-prospected microalgae isolates. The multidimensional statistical design enabled the optimisation of 12 critical nutrients (N, P, Ca, Mg, Fe, Cu, Mn, Zn, B, Se, V and Si) and identified the highest specific-growth rates, elemental main-effects (Ca, Mg and Zn accounted for 71% of all main effects under photoautotrophic conditions) and pair-wise nutrient interactions (e.g. Ca-Mg, Mg-Zn, B-Zn, B-Se, Mn-Zn and Zn-Si) for each of the 100 strains tested (25,100 trials, over 2000-fold data-compression compared to a full factorial design) as well as their ability to use different carbon sources. Photoautotrophic growth rates reaching 0.067 h− 1 (0.289 h− 1 at microwell plate scale) and 2.78 g L− 1 (batch cultivation in flasks) are amongst the highest reported, promoting the capacity for a high-throughput optimisation of microalgae production processes using established and newly bio-prospected strains.