Comparative evaluation of modified m-FC and m-TEC media for membrane filter enumeration of Escherichia coli in water.
Two media used to detect fecal coliforms in water by membrane filtration, m-FC and m-TEC, were modified and supplemented with the chromogenic substrate 5-bromo-6-chloro-3-indoyl-beta-D-glucuronide (BCIG) and were compared for quantitative recovery of Escherichia coli. Student's t test of data from 181 water samples of sewage, rivers, lakes, and wells did not demonstrate any statistically significant differences (P = 0.05) in the enumeration of E. coli with these media. Target colonies were confirmed to be E. coli at rates of 98.6 and 97.3% by using FC-BCIG and TEC-BCIG media, respectively. Glucuronidase-negative isolates of E. coli were encountered at the same frequency (6.0%) on both media. This collaborative study demonstrated that either modified basal medium could be used successfully for detection of E. coli in various nontreated waters within 24 h.
Ontario Ministry of Health, Laboratory Services Branch, Toronto, Canada.
B W
BW
Ciebin
M H
MH
Brodsky
R
R
Eddington
G
G
Horsnell
A
A
Choney
G
G
Palmateer
A
A
Ley
R
R
Joshi
G
G
Shears
D015169:Colony Count, Microbial / Q000379:methods* / Q000706:statistics & numerical data; D003470:Culture Media; D004926:Escherichia coli / Q000302:isolation & purification*; D005069:Evaluation Studies as Topic; D005243:Feces / Q000382:microbiology; D006801:Humans; D008851:Micropore Filters; D014871:Water Microbiology; D014881:Water Supply
D003470:Culture Media