Study of changes in bacterial and viral abundance in formaldehyde-fixed water samples by epifluorescence microscopy.

Accurate measurement of bacterial and viral abundance in coastal marine environments is important to understand the dynamics of microbial communities in these ecosystems. In this study, the effect of formaldehyde preservation on the abundance of bacteria and viruses in water samples from Cochin Backwater was determined by SYBR Green I staining and epifluorescence microscopy. The counts were determined for 45 days in samples fixed with 1-6% formaldehyde.