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. 1984 Aug;48(2):371–375. doi: 10.1128/aem.48.2.371-375.1984

Evaluation of m-T7 agar as a fecal coliform medium.

M W LeChevallier, P E Jakanoski, A K Camper, G A McFeters
PMCID: PMC241520  PMID: 6385849

Abstract

m-T7 agar, designed to improve recoveries of injured total coliforms, was evaluated for its effectiveness as a fecal coliform medium. The time and temperature of preincubation were found to be crucial to the optimal recovery of fetal coliforms. Isolation rates for fecal coliforms on m-T7 agar from sewage effluents were the highest when plates were preincubated at 37 degrees C for 8 h before transfer to 44.5 degrees C for 12 h. The medium was found to produce consistently higher fecal coliform counts than all the other methods tested. Recoveries were 3.1 times greater than the standard m-FC method and 1.7 times greater than the two-layer enrichment, temperature acclimation procedure. Verification rates for fecal coliforms isolated on m-T7 agar averaged 89.0%, whereas verification rates for m-FC agar averaged only 82.8%. Both media isolated similar fecal coliform populations. The advantages of a single medium, highly effective for the isolation of both total and fecal coliforms, are discussed.

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Selected References

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

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