An Underexplored Resource for Biotechnology: Selected Microphytes of East African Soda Lakes and Adjacent Waters

Abstract

Microphytes (Cyanobacteria and algae) are amongst the most promising sustainable resources for high-quality compounds, but high expenditures for culturing, harvesting and subsequent processing complicate their exploitation. An economic way to reduce costs of algal mass cultures is to install open-pond culture systems in tropical regions, which guarantee high solar irradiance throughout the year, but this approach is still waiting to be introduced in East Africa. One essential but often neglected requirement to carry out successful microphytean mass cultures is strain selection. We provide a selection of high-yielding microphytes with high potential for biotechnology use collected in the soda lakes and adjacent systems such as salt evaporation ponds or sewage oxidation ponds. Microphytes were detected as field clones or cultured strains and identified via microscopy and molecular methods; SSU rRNA and/or ITS sequences were entered in the NCBI database. Besides the well-known and already commercially exploited cyanobacterium Arthrospira, promising relatives of the famous “green balls” Chlorella, members of the green algal genera Selenastrum, Picocystis and Mychonastes and the eustigmatophytes Nannochloropsis and Microchloropsis are presented. All of them are suitable for ex situ conservation in strain collections, which is the basis for future mass cultivation and commercial use.