An optimal culture medium for growing Karlodinium veneficum: Progress towards a microalgal dinoflagellate-based bioprocess

•A new optimal medium for culturing Karlodinium veneficum is reported.•New medium outperforms the standard L1 medium in producing cells and bioactives.•A genetic algorithm based strategy is proved for medium development.•The need for species-dependent optimization of the culture media is reinforced.

In addressing a potential bioprocess for bioactives production from microalgae, the choice of a proper culture medium is a key factor. In the present work, an optimal culture medium for producing the marine dinoflagellate microalga Karlodinium veneficum was formulated using a stochastic search strategy based on genetic algorithm. The optimized formulation had 25 components including the macronutrients, trace elements and vitamins. With this medium, the final attainable cell concentration during batch growth was enhanced by 120% relative to the control culture grown in the L1 medium. The final titer of the bioactive karlotoxins measured using the hemolytic activity of the culture filtrate was enhanced by 190% relative to the L1 control. These results are a promising basis for further development of photobioreactor culture strategies for microalgal dinoflagellates.