Total viable organism

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Total viable organism (or TVO) is a term used in microbiology to quantify the amount of microorganisms present in a sample. [1] Each sample is usually cultured on a variety of agar plates (petri dishes) often containing different types of selective media. The colony-forming units (CFUs) are calculated after allowing time for growth.

TVO numbers are used to quantify the CFUs for a given amount of sample and often include dilution factors. For example, a 1 mL sample of water containing 10 CFUs on one plate would have a TVO value of 10 cfu/mL.

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References

  1. Massicotte, Richard; Mafu, Akier A; Ahmad, Darakhshan; Deshaies, Francis; Pichette, Gilbert; Belhumeur, Pierre (2017). "Comparison between Flow Cytometry and Traditional Culture Methods for Efficacy Assessment of Six Disinfectant Agents against Nosocomial Bacterial Species". Frontiers in Microbiology. 8: 112. doi: 10.3389/fmicb.2017.00112 . PMC   5289957 . PMID   28217115.