A dynamic resazurin microassay allowing accurate quantification of cells and suitable for acid-forming bacteria

J Microbiol Methods. 2021 Apr:183:106172. doi: 10.1016/j.mimet.2021.106172. Epub 2021 Feb 18.

Abstract

A resazurin micro-assay was developed to quantify acidifying bacteria. The resorufin fluorescent signal was measured over time and the determined time to reach the max slope (TMS) was plotted against CFU (colony forming unit) counts. This dynamic assay enabled to quantify nine lactic acid bacteria and a Bacillus licheniformis strain despite the increasing acidity of the medium.

Keywords: Fluorescence; Lactic acid bacteria; Resazurin microassay; Viability quantification.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acids / metabolism*
  • Bacillus licheniformis / chemistry
  • Bacillus licheniformis / growth & development
  • Bacillus licheniformis / metabolism
  • Bacteriological Techniques / methods*
  • Culture Media / chemistry
  • Culture Media / metabolism
  • Fluorescence
  • Lactobacillales / chemistry
  • Lactobacillales / growth & development*
  • Lactobacillales / metabolism
  • Oxazines / chemistry*
  • Oxazines / metabolism
  • Xanthenes / chemistry*
  • Xanthenes / metabolism

Substances

  • Acids
  • Culture Media
  • Oxazines
  • Xanthenes
  • resazurin