Evaluation of m-T7 agar as a fecal coliform medium.
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.
D000362:Agar; D003470:Culture Media; D004755:Enterobacteriaceae / Q000254:growth & development* / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology*; D006801:Humans; D008828:Microbiological Techniques; D012722:Sewage; D013696:Temperature
D003470:Culture Media; D012722:Sewage; D000362:Agar