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. 1978 Jul;36(1):90–94. doi: 10.1128/aem.36.1.90-94.1978

Modification of M-FC medium by eliminating rosolic acid.

W G Presswood, D K Strong
PMCID: PMC243039  PMID: 358922

Abstract

Eliminating rosolic acid from M-FC medium improves the MFC procedure by allowing higher fecal coliform colony recoveries with greater ease in counting. Samples of unchlorinated and chlorinated domestic sewage, creek, lake, and river water were analyzed for fecal coliforms by standard procedures. Results of 200 comparisons of fecal coliform counts on M-FC medium without and with rosolic acid showed that higher counts were obtained 71% of the time when rosolic acid was excluded without an overgrowth of background colonies. Results from analyzing chlorinated sewage showed that eliminating rosolic acid improved the recovery of fecal coliform bacteria by 49%. A total of 1,675 blue colonies and 766 nonblue colonies were verified. Of the 1,675 blue colonies, 1,566 were confirmed as fecal coliform bacteria, for a verification of 93.5%. The percent verification of nonblue colonies as noncoliform bacteria was 84.2% (644/766).

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bronfenbrenner J., Schlesinger M. J., Soletsky D. On Methods of Isolation and Identification of the Members of the Colon-Typhoid Group of Bacteria: The Study of Bactericidal Action of CR Indicator. J Bacteriol. 1920 Jan;5(1):79–87. doi: 10.1128/jb.5.1.79-87.1920. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. CLARK H. F., GELDREICH E. E., KABLER P. W., BORDNER R. H., HUFF C. B. The coliform group. I. The boric acid lactose broth reaction of coliform IMViC types. Appl Microbiol. 1957 Nov;5(6):396–400. doi: 10.1128/am.5.6.396-400.1957. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. GELDREICH E. E., CLARK H. F., KABLER P. W., HUFF C. B., BORDNER R. H. [The coliform group. II. Reactions in EC medium at 45 C]. Appl Microbiol. 1958 Sep;6(5):347–348. doi: 10.1128/am.6.5.347-348.1958. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Perry C. A., Hajna A. A. Further Evaluation of EC Medium for the Isolation of Coliform Bacteria and Escherichia coli. Am J Public Health Nations Health. 1944 Jul;34(7):735–738. doi: 10.2105/ajph.34.7.735. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Scheusner D. L., Busta F. F., Speck M. L. Inhibition of injured Escherichia coli by several selective agents. Appl Microbiol. 1971 Jan;21(1):46–49. doi: 10.1128/am.21.1.46-49.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]

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