Productivity Testing of A1 Media

John Gentile yjgent at
Mon Jan 5 21:22:59 EST 2004

It looks like you should work backwards and prepare your media starting with
the 15 day old stuff and then 3 days later the 12 day stuff, etc until you
get to the 1 day (actually 0 day for the freshest media). Then on that 15th
day inoculate all your tubes from the same sample. That way you can easily
see when each set shows growth. Make sure you have enough sample for all
those tubes and that it is really mixed well.

Personally I always dreaded the MPN technique and would rather do a filter
culture of 100 cc planted on Levine EMB. But I haven't done coliform counts
in many years - don't really miss it.

in article e8c7403b.0401042332.6a19c2fb at, Pete at
petethompson at wrote on 1/5/04 2:32 AM:

> I'm looking to set up an experiment to determine whether or not A1
> media (used for feacal coliform determination - MPN technique)with
> different preparation dates produces significantly different numerical
> results when inoculated with the same original sample/samples.
> Media of varying ages (ie day 1, day 3, day 5, day 7, day 9, day 12,
> day 15)will be used.
> Any suggestions on the best way of performing this experiment?

John Gentile MS M(ASCP)                     yjgent at
Laboratory Information, QA Manager
VA Medical Center
Providence, RI

The contents of this message are mine personally and do not reflect any
position of the Government or VA.

More information about the Microbio mailing list