Three New Synthetic Algal Culture Media to Grow Them All^†

Abstract

Three new synthetic algal culture media are described that have been used to cultivate ~12,000 diverse strains of (micro)algae, one culture medium for marine and brackish-water algae (ASP-MEL (Artificial Seawater Provasoli-MELKONIAN)), and two culture media for freshwater/terrestrial algae (SFM (Synthetic Freshwater Medium) and W-MEL (Waris-MELKONIAN)). The genesis of the three media since their original formulation and the rationale for modifications of these media over the past 50 years are outlined. A complex trace element mix derived from an enriched natural seawater culture medium (L1) is used in all three media, and allows the omission of soil water extract from one freshwater culture medium (W-MEL). It is suggested that the inclusion of selenite renders soil extract in algal culture media superfluous. Prospects and limitations of the three synthetic algal culture media as general-purpose media for large collections are discussed.

Keywords

Algae / Synthetic culture media / ASP-MEL / SFM / W-MEL / Culture collections / Selenite

Acknowledgments

The authors are indebted to the Max Planck Institute for Plant Breeding Research (Cologne, Germany) for hosting them as Senior Guest Fellows since July 2020.

Author Contributions

Both authors (B.M. and M.M.) contributed equally to this manuscript and the research described therein. Conceptualization, B.M. and M.M.; Methodology, B.M. and M.M.; Software, B.M. and M.M.; Validation, B.M. and M.M.; Formal Analysis, B.M. and M.M.; Investigation, B.M. and M.M.; Resources, B.M. and M.M.; Data Curation, B.M. and M.M.; Writing, B.M. and M.M.; Project Administration, B.M. and M.M.; Funding Acquisition, M.M.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All research data linked to this manuscript are included in the manuscript. For further information contact the corresponding author.

Funding

This research received no external funding. Research in the authors’ laboratory has been generously funded over the past 47 years by the German Research Foundation (DFG).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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