Desmid Medium is often helpful in isolating microalgae species as the major component is soil water.

Have you tried solid media? Freshwater microalgae grown very well on solid media with 0.7% agar. Try to make a dilution, put on a petri dish and after some days colonies should show up. Then you can choose the colony from your specie of interest. The book added has some good information about that.

Good luck!

thank you for your answers

good luck

Hi,

Procedure (well explained in the Andersen book mentioned above): you probably need to use the "capillar pipette" isolation technique.Take a pasteur pipette, hold the thin part over an alcohol burner (take a forceps to hold the tip). As the glass becomes soft, put away the tip (forceps) from the upper part. the result will be a very thin capillar between the tip and the upper part. Remove the thicker tip.

Take a raw sample on a microscope slide, use 10x objective and search for the specific Kirchneriella. Tip with the capillar pipette into the area of the respective colony. You will realize that the cells are sucked into the pipette. Place these cells in a separate drop of sterile medium. Repeat the procedure a few times until only the taxon of interest is there (rewashing of the colonies). Put it then in sterile medium.

Medium: There exist soooo many media. I suggest trying three different ones, which are commonly, such as desmids, BG11 or Chu10. Also mixing them is one option. The cultivation success can be increased further, if you dilute the respective medium with sterilized and filtrated original water, from where the sample was taken.

All the best, Michael

thanks