PMFLIST Archives

October 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:
"Knutsen, Chris" <[log in to unmask]>
Reply To:
The Pharmaceutical Microbiology Forum Email List <[log in to unmask]>
Date:
Fri, 4 Oct 2019 12:18:20 +0000
Content-Type:
text/plain
Parts/Attachments:
text/plain (222 lines)
I would be happy to be corrected by real experts in the field, like Don English, but in my humble opinion a preservative is meant to be just that, a preservative.  It is intended to not allow growth of microorganisms in a product, and assumes that the product has been made following relevant good manufacturing controls, whether GMP or gmp.  They are not meant to correct problematic controls, such as the formation of biofilms.  Biofilms are notoriously difficult to get rid of, requiring very strong disinfectants like peracetic acid, often with multiple applications. Just ask anyone who has struggled with a biofilm in a water system.

That said, in my deep dark past, I dealt with a customer's preserved sample that had microbial growth on storage in a refrigerator.  The product passed the standard AET battery of organisms, but the contaminant, when isolated showed that is was stable against the preservative system.    The bugs obviously hadn't read Seymour Block's book. This example points out two things. Be careful of the claims, and be  rigorous in your microbial control programs. That bug shouldn't have been in the product to start with.


Chris Knutsen, Ph.D.
Technical Fellow
ASO Microbiology Center of Excellence
Bristol-Myers Squibb Company
1 Squibb Drive
New Brunswick, NJ 08902
Tel : +1-732-227-5375
Fax: +1-732-227-3071
Cell: +1-609-751-8362
e-mail: [log in to unmask]

-----Original Message-----
From: The Pharmaceutical Microbiology Forum Email List <[log in to unmask]> On Behalf Of Richard Albert
Sent: Wednesday, October 2, 2019 8:27 AM
To: [log in to unmask]
Subject: Re: [PMFLIST] USP <51> AET Cultures - Fresh vs Premade

[Use CAUTION when opening links/attachments]

I will take this opportunity to share the following.  The question I have always had about USP <51> is how 'real' world it is.  Real world microbiology is not a microbe growing in a Petri dish.  I have seen formulations containing preservatives be very effective when evaluated according to USP <51>.  However the preservatives were not effective when the microbial growth was as a biofilm.  Has anyone else observed something similar or evaluated preservative effectiveness against microbial growth as a biofilm.

Richard A. Albert
Senior Microbiologist
Kleen Test Products



On Tue, Oct 1, 2019 at 5:04 PM Robert Pritchett < [log in to unmask]> wrote:

> Hello all,
>
> USP <51> AET has the following text regarding preparation of test strains:
>
> "Use standardized suspensions of test strains or prepare as stated below."
> "The viable microorganisms used in the procedure should be part of a
> freshly growing culture (e.g., in logarithmic growth phase) with the
> exception of A. brasiliensis spores."
>
> I've encountered at least one contract lab who uses pre-made
> commercially available lyophilized cultures specifically marketed for
> AET. The lyophilized cultures are hydrated and then used for testing
> and that lab tells me they consider this the mentioned "standardized
> suspensions" from the USP text. The contract laboratory does perform
> proper method suitability using the premade AET cultures with passing
> results and I have seen the validation work for using AET pre-made
> cultures, but I still question the acceptability of the practice.
>
> My personal opinions/talking points are as follows:
> - Why? It's simpler and more cost effective to start a fresh culture
> and any analyst with the title microbiologist should be able to adjust
> suspensions accordingly
> - Introducing recently desiccated, starved, frozen, and stressed cells
> as a challenge to a preservative system seems like a very bad idea - a
> weak preservative system might pass when it would otherwise fail when
> challenged with fresh cultures
> - The validation work cannot possibly represent the varied materials
> and preservative systems that may be tested for AET
>
> At this time, I've requested laboratories performing AET for my site
> to always use fresh cultures.
>
> With that said, I'm open to hear what others may say on the topic. Can
> anybody defend using pre-made commercial cultures for AET?
>
> -RP
>
>
>
> This message is intended solely for the designated recipient(s). It
> may contain confidential or proprietary information and may be subject
> to attorney-client privilege or other confidentiality protections. If
> you are not a designated recipient you may not review, copy or
> distribute this message. If you receive this in error, please notify
> the sender by reply e-mail and delete this message. Thank you.
>
> ------------------
> The PMFList
> (https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmicr
> obiologynetwork.com%2Fpmflist.asp&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240408798&amp;sdata=kVzvFuPEyi07pAjEAlUPEl%2BFw%2BQLl9X87pys%2BaGJXoU%3D&amp;reserved=0) is operated from The Microbiology Network (https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmicrobiologynetwork.com&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240408798&amp;sdata=s2hEhd41WDpJUD9ku%2BbKDINnRMjXyOD3ebeqd6x9nqw%3D&amp;reserved=0) 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://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.
> scienceboard.net%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16
> ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0
> %7C637056296240408798&amp;sdata=cYX5XYXXbBt%2FskwV9rhnlASR%2BRFLXJiHvK
> StjXVxjvU%3D&amp;reserved=0
>
> Steris -
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.s
> terislifesciences.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C
> 1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C
> 0%7C0%7C637056296240408798&amp;sdata=wgIDq3bsC7FXC4F0j9Q4Mn7P%2F28WsEJ
> Rldv7wcZqQO4%3D&amp;reserved=0
>
> Charles River Laboratories -
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.c
> river.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f027
> 4950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C6370
> 56296240408798&amp;sdata=6pX1xH4cVx5KFOmNx%2Bxfu17zfEc1Fa11EQUpGnvDYbE
> %3D&amp;reserved=0
>
> Veltek Associates, Inc -
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.s
> terile.com&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f02749
> 50352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056
> 296240408798&amp;sdata=T%2B2wRy2eNiVe5PUfa8uSpHMQ061KoaQTn3Rr5yE5hAI%3
> D&amp;reserved=0
>
> Microbiologics, Inc. -
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.m
> icrobiologics.com&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac
> 4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7
> C637056296240408798&amp;sdata=vWUVoW3P2kbD4970aQ%2BpN%2FCQuvyTTYT6iOYm
> cYJcqAA%3D&amp;reserved=0
>
> BD Industrial Media -
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.b
> d.com%2Fds%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f02
> 74950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637
> 056296240408798&amp;sdata=pgkHv6ctLfSw8%2B5s8sWWpJVjvzPRDAslAHpLFLC4Xt
> 0%3D&amp;reserved=0
>
> Boston Analytical
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.b
> ostonanalytical.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1f
> c16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%
> 7C0%7C637056296240418807&amp;sdata=jzfrjLgXlk9LvSK%2BaDG5Xu%2BE%2F4H2D
> gZWcPBawaMRfqU%3D&amp;reserved=0
>
> Associates of Cape Cod, Inc. -
> https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.a
> cciusa.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f02
> 74950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637
> 056296240418807&amp;sdata=efUWVjmx2p%2BP%2FQRgSfF6z%2Fgni7XVbcxiKgGTMt
> WkV9k%3D&amp;reserved=0
>
>
> =================================
> 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.
>

--
CONFIDENTIALITY NOTICE:
This e-mail may contain trade secrets or privileged, undisclosed or otherwise confidential information. If you have received this e-mail in error, you are hereby notified that any review, copying or distribution of this message in whole or in part is strictly

prohibited. Please inform the sender immediately and destroy the original transmittal. Thank you for your cooperation.

------------------
The PMFList (https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmicrobiologynetwork.com%2Fpmflist.asp&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=beRDU8ucjQCcHBH8oE6fsuqWQ8aLUTOe%2BlwItXGGgSM%3D&amp;reserved=0) is operated from The Microbiology Network (https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmicrobiologynetwork.com&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=AYcStRaRwqxcZgbu8LWGPMk8V9QDJkgyFRXKyYxHVBs%3D&amp;reserved=0) 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://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.scienceboard.net%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=VanXgUhNIy96icn0Yh5fHt1tyePP%2BZG9LbPfJKI1N1Y%3D&amp;reserved=0

Steris - https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.sterislifesciences.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=%2B2Da23%2FeKb3djE3ZCzE0voskGfbUPTW9zTDnWYqs8yU%3D&amp;reserved=0

Charles River Laboratories - https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.criver.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=tAwwUVuJol64vG%2FO977gXRyl%2BdIcjm7ol4oMcoRL0cE%3D&amp;reserved=0

Veltek Associates, Inc - https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.sterile.com&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=Wyo96PrwI0TvgUUfVadmFPvHR3Pdb%2Fyg72UQDZXmwVs%3D&amp;reserved=0

Microbiologics, Inc. - https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.microbiologics.com&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=KOrxlgBhjK0JvMnFyYfRZ38xeZrpKbUoRfnT1VWuGaI%3D&amp;reserved=0

BD Industrial Media - https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.bd.com%2Fds%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=%2F4C3kYDaDMWCcl3kP3%2BGEs%2Bsv5OMoeqvM%2BgGdbpe0RU%3D&amp;reserved=0

Boston Analytical https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.bostonanalytical.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=jzfrjLgXlk9LvSK%2BaDG5Xu%2BE%2F4H2DgZWcPBawaMRfqU%3D&amp;reserved=0

Associates of Cape Cod, Inc. - https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.acciusa.com%2F&amp;data=02%7C01%7Cchris.knutsen%40BMS.COM%7C1fc16ac4f0274950352808d747537e10%7C71e34cb83a564fd5a2594acadab6e4ac%7C0%7C0%7C637056296240418807&amp;sdata=efUWVjmx2p%2BP%2FQRgSfF6z%2Fgni7XVbcxiKgGTMtWkV9k%3D&amp;reserved=0


=================================
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.
________________________________
 This message (including any attachments) may contain confidential, proprietary, privileged and/or private information. The information is intended to be for the use of the individual or entity designated above. If you are not the intended recipient of this message, please notify the sender immediately, and delete the message and any attachments. Any disclosure, reproduction, distribution or other use of this message or any attachments by an individual or entity other than the intended recipient is prohibited.

------------------
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