Comparison of techniques for counting prokaryotes in marine planktonic and biofilm samples

Though a large number of techniques are available for the study aquatic bacteria, aim this was to establish technique analysing free-living and biofilm prokaryotic cells through laboratory assays. In particular, we wished analyse efficiency ultrasound detach disrupt biofilm, obtain an efficient stain treatment quantifying prokaryotes in flow cytometry (FC), compare epifluorescence microscopy (EFM), scanning electron (SEM) FC prokaryotes#. Marine-grade plywood substrates were immersed natural marine water that conditioned 12 days. At 6 days, aliquots removed estimate prokaryote density. Ultrasound efficiently from (up 94%) without cell damage. analysis (unstained) reliably quantified plankton young or mature compared with other staining (acridine orange, 4′,6-diamidino-2-phenylindole, propidium iodide green fluorescent nucleic acid), EFM SEM techniques. achieved similar results, while high variability observed technique. faster more precise than because count is not dependent on observer.