PMFLIST Archives

November 2019

PMFLIST@LISTS.MICROBIOLOGYNETWORK.COM

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Nilesh Shah <[log in to unmask]>
Reply To:
The Pharmaceutical Microbiology Forum Email List <[log in to unmask]>
Date:
Mon, 18 Nov 2019 00:16:52 +0530
Content-Type:
text/plain
Parts/Attachments:
text/plain (195 lines)
Dear Donald Sir and forum team

My query is I have validated product with 1 g sample in 9 ml diluent and
after validation can I use 10 g sample in 90 ml diluent during routine
testing?

Thanks & Regards
Nilesh



On Thu, 14 Nov 2019, 09:22 Donald English, <[log in to unmask]>
wrote:

> Dear Nilesh,
>
> For validating an enrichment test with a 10-gram sample amount into 90 or
> 490 ml of enrichment broth you should always use an inoculum of 10 to 100
> CFU/0.1 ml for each test organism in order to ensure that you are able to
> detect low levels by enrichment .
>
> To answer your question about using a 1.0 gram or 10-gram test sample to
> validate a plate count method for a 1:10 dilution, a different approach
> needs to be made and the math is as follows for validating with less than
> 100 CFU.:
>
> 1.0   gram sample amount for each test microorganism:
>
> 1.0-gram of test sample + 8.9-ml of microbial count diluent + 0.1-ml of
> inoculum with less than 1000 CFU = the final count should be less than 100
> CFU/ml if there are no adverse effects.
>
> Control:
>
> 9.9-ml of microbial count diluent + 0.1-ml of inoculum with less than 1000
> CFU   = final count should be less than 100 CFU/ml
>
> For a 10-gram test sample, everything needs to be multiplied by 10 for each
> test microorganism:
>
> 10-grams of test sample + 89-ml of microbial count diluent +1.0-ml inoculum
> with less than 10,000 CFU  =   the final count should be less than 100
> CFU/ml if there are no adverse effects
>
> Control:
>
> 99.0-ml of microbial count diluent + 1.0-ml of inoculum with less than
> 10,000 CFU   =  the final count should be less than 100 CFU/ml
>
> A comparison of the 1:10 dilutions for the test sample and control for each
> test organism is made for each test microorganism to validate a plate count
> procedure for a test sample.
>
> From the math conducted above, it does not matter if a 1.0 or 10-gram test
> sample is used for validating a test sample plate count method because the
> results should be the same.
>
> As far as incubation, I would always try to incubate the plate count
> plates, enrichment broths and selective/differential media for the minimum
> time periods that are present in USP Chapters 60, 61, and 62..
>
>  Regards,
>
> Don
>
>  Donald J. English Microbiological Quality Consulting LLC
>
> Florham Park, New Jersey 07932
>
>
> On Wed, Nov 13, 2019 at 12:52 PM Nilesh Shah <[log in to unmask]>
> wrote:
>
> > Dear Forum members,
> >
> > Query on Mlt validation.
> > 1.Can I use 1 g sample in 9 ml diluent and after validation can we use
> 10 g
> > sample in 90 ml diluent during routine testing.
> >
> > 2.for positive control and product positive control minimum incubation to
> > be followed and for product control maximum incubation to be followed.
> >
> > 3.culture concentration used for specified organisms should be nmt 100
> cfu
> > in total volume.
> >
> > Thanks
> > Nilesh
> > 9820919185
> >
> > ------------------
> > The PMFList (http://microbiologynetwork.com/pmflist.asp) is operated
> from
> > The Microbiology Network (http://microbiologynetwork.com) and supported
> by
> > our sponsors as a service to the scientific community.
> >
> > Please take a second to visit our sponsors' web sites and say thank you
> > for their support of this service.
> > If your company would be interested in sponsoring this community, please
> > contact [log in to unmask]
> >
> >
> >
> > Science Advisory Board https://www.scienceboard.net/
> >
> > Steris - http://www.sterislifesciences.com/
> >
> > Charles River Laboratories - http://www.criver.com/
> >
> > Veltek Associates, Inc - http://www.sterile.com
> >
> > Microbiologics, Inc. - http://www.microbiologics.com
> >
> > BD Industrial Media - http://www.bd.com/ds/
> >
> > Boston Analytical http://www.bostonanalytical.com/
> >
> > Associates of Cape Cod, Inc. - http://www.acciusa.com/
> >
> >
> > =================================
> > The nature of this service is to provide a medium for communication.  The
> > specific statements and endorsements of individuals participating in the
> > discussions are not necessarily those of The Microbiology Network, Inc.,
> > the PMF, or the sponsors of the list.
> >
>
> ------------------
> The PMFList (http://microbiologynetwork.com/pmflist.asp) is operated from
> The Microbiology Network (http://microbiologynetwork.com) and supported by
> our sponsors as a service to the scientific community.
>
> Please take a second to visit our sponsors' web sites and say thank you
> for their support of this service.
> If your company would be interested in sponsoring this community, please
> contact [log in to unmask]
>
>
>
> Science Advisory Board https://www.scienceboard.net/
>
> Steris - http://www.sterislifesciences.com/
>
> Charles River Laboratories - http://www.criver.com/
>
> Veltek Associates, Inc - http://www.sterile.com
>
> Microbiologics, Inc. - http://www.microbiologics.com
>
> BD Industrial Media - http://www.bd.com/ds/
>
> Boston Analytical http://www.bostonanalytical.com/
>
> Associates of Cape Cod, Inc. - http://www.acciusa.com/
>
>
> =================================
> The nature of this service is to provide a medium for communication.  The
> specific statements and endorsements of individuals participating in the
> discussions are not necessarily those of The Microbiology Network, Inc.,
> the PMF, or the sponsors of the list.
>

------------------
The PMFList (http://microbiologynetwork.com/pmflist.asp) is operated from
The Microbiology Network (http://microbiologynetwork.com) and supported by
our sponsors as a service to the scientific community.

Please take a second to visit our sponsors' web sites and say thank you for their support of this service.
If your company would be interested in sponsoring this community, please contact [log in to unmask]



Science Advisory Board https://www.scienceboard.net/

Steris - http://www.sterislifesciences.com/

Charles River Laboratories - http://www.criver.com/

Veltek Associates, Inc - http://www.sterile.com

Microbiologics, Inc. - http://www.microbiologics.com

BD Industrial Media - http://www.bd.com/ds/

Boston Analytical http://www.bostonanalytical.com/

Associates of Cape Cod, Inc. - http://www.acciusa.com/


=================================
The nature of this service is to provide a medium for communication.  The specific statements and endorsements of individuals participating in the discussions are not necessarily those of The Microbiology Network, Inc., the PMF, or the sponsors of the list.

ATOM RSS1 RSS2