THE PRODUCTION OF CLONAL AND AXENIC CULTURES OF MICROALGAE USING FLUORESCENCE-ACTIVATED CELL SORTING

Unialgal cultures of the flagellate algae Cyanophora paradoxa, Haemato coccus lacustris, Monomastix sp., Scherffelia dubia and Spermatozopsis similis which contained bacteria were sorted by flow cytometry to obt ain axenic clonal cultures. The variables used for fluorescence-activa ted cell sorting (FACS) were chlorophyll autofluorescence, forward sca tter and side scatter of the laser beam. To produce clonal cultures, a single cell was sorted into each culture flask. Depending on the spec ies, about 20-30% of the sorted cultures grew successfully and at leas t 20% of these were axenic even if the numerical ratio between bacteri a and algae in the original cultures was as high as 300:1. FACS repres ents an effective and rapid method for the preparation of clonal and a xenic cultures of microalgae.