Microplates as a microreactor platform for microalgae research

Abstract

High-throughput platforms for microalgae screening are not yet commercially available. In this study, the feasibility of 96-well microplates was analyzed for microalgae research. Equivalence among wells, as culture microreactors, was investigated in controlled high CO2 conditions. Specific growth rates of two microalgae species, Scenedesmus sp. UTEX1589 and an environmental isolate, were significantly higher in border wells than in internal positions. Furthermore, growth rate gradients analyzed as contours throughout the platform were observed for Scenedesmus sp. However, the output variable exhibited high precision associated with a low coefficient of variation (CV), between 6.8 and 7.8%. In a demonstrative experiment to determine the effect of culture media dilution on six microalgae species, treatments were randomized in the central subset of a microplate. Results were consistent and statistically sound (CV 9.4-12.9%), and showed that microalgae species could grow with no detrimental effect in 50% (v/v) dilution of the culture medium. Provided border wells exclusion and a randomized design, 96-well microplates are a practical and statistical robust platform for microalgae research.

Design and validation of a parallelized micro‐photobioreactor enabling phototrophic bioprocess development at elevated throughput

“…In this context, inhomogeneous illumination patterns were described to display problems. Moreover, growth phenotypes, likely induced by ventilation or temperature effects within the incubation chamber (Pacheco et al, ) or uneven CO 2 mass transfer into the wells (Han et al, ), were observed. With regard to extended cultivation times, evaporation control needs to be evaluated carefully, as high liquid loss may distort cultures’ performance (Betts et al, ; Silk et al, ).…”

Growth of a common planktonic diatom quantified using solid medium culturing

“…All known microbial micro-cultivation growth and phenotyping techniques, using liquid or solid media, suffer from biases imposed by the so-called edge effect, where the growth characteristics of the individuals are affected by their position on the plate relative to the edge 16 , 27 . For the techniques involving solid medium, the situation is further complicated by the neighboring colony-imposed effects, which scale with the resolution of the method 1 .…”

Optimization of a high‐throughput phenotyping method for chain‐forming phytoplankton species

“…The method proposed here can be used for cultivation and measuring platform, however, we want to highlight the presence of variations associated to plate growth that have been described in this and a previous study (Pacheco et al 2013). The conclusive data analysis must include modeling to control for the temporal and spatial-specific variability inherent to the methodological set-up.…”

“…Phenotyping of chain-forming phytoplankton the model M1 captured 33% more of the variation than model M0. This result suggested that a substantial proportion of the variation in the data is due to temporal variation (variation between experimental runs), which agrees with previous findings demonstrating variability in microalgal growth on multi-well plate (Pacheco et al 2013).…”

“…A randomized setup of the plates is advisable. However, contrary to Pacheco et al (2013), we do not advocate that border wells be discarded. Although we encountered spatial bias, especially toward the edges of the plates much similar to what has previously been described, a model that adjusts for this type of variation will efficiently account for it.…”