Intrinsic autotrophic biomass yield and productivity in algae: experimental methods for strain selection

Area of Science:

• * Biotechnology and Algal Cultivation
• * Photosynthetic Efficiency and Biomass Production

Background:

• * Accurate estimation of algal photoautotrophic yield (Φ(DW)) is vital for selecting optimal algal strains and growth conditions for industrial biomass production.
• * Traditional methods often face limitations, such as carbon availability, making yield estimation unreliable.

Purpose of the Study:

• * To derive and validate a method for estimating algal photoautotrophic yield (Φ(DW)) using batch culture behavior.
• * To assess the suitability of the FLX growth medium for high-throughput algal cultivation and yield determination.
• * To compare the reliability of biomass yield versus maximum growth rate as indicators for algal production.

Main Methods:

• * Development of a carbonate addition method to overcome carbon limitations in aerated batch cultures.
• * Derivation of algal photoautotrophic yield (Φ(DW)) from batch growth data under known light conditions.
• * Utilizing the fully defined FLX growth medium (FLX1-100) with variable ionic strengths for testing.

Main Results:

• * The carbonate addition method resulted in two to five-fold higher yield estimates compared to standard aerated cultures.
• * Algal photoautotrophic yield (Φ(DW)) proved to be a more reliable indicator for large-scale production than maximum growth rate.
• * The FLX medium supported excellent growth and was well-suited for high-throughput screening with small sample volumes.

Conclusions:

• * The developed method and FLX medium provide a robust framework for accurate algal biomass yield assessment.
• * This approach is critical for efficient strain selection and optimization of conditions for industrial algal cultivation.
• * The study highlights the importance of addressing carbon limitations for reliable photoautotrophic yield determination.