Comparison of Direct Microbial Count Procedures for Planktonics and Sessiles Enumeration

Barbara Speranza, Angela Racioppo, Antonio Bevilacqua, Milena Sinigaglia, Clelia Altieri

Department of the Science of Agriculture, Food and Environment (SAFE), University of Foggia, Foggia, Italy.

DOI: 10.4236/fns.2014.521214                

Abstract

In the present investigation, the sensitivity of different direct microbial count procedures applied on systems containing both planktonics and sessiles was tested. The direct count pour plate was compared with direct epifluorescent microscopic enumerations in order to evaluate the efficiency of the studied techniques in giving information about microbial activity or viability. Our results indicate that the standard plate count procedure is the most sensitive method to estimate viable and cultivable planktonic cells. On the other hand, direct enumeration by epifluorescent microscopy may become an interesting alternative to count sessile cells.

Keywords

Direct Viable Count, Biofilm, Epifluorescence Microscopy, Fluorochromes

Conflicts of Interest

The authors declare no conflicts of interest.

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