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October 1998


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Tony & Roz Cundell <[log in to unmask]>
Reply To:
The Pharmaceutical Microbiology Mail List <[log in to unmask]>
Thu, 8 Oct 1998 22:37:46 -0400
text/plain (41 lines)
At 11:20 AM 10/7/98 -0400, you wrote:
>Here is a question for my Microbiology family members.
>Do we need to do any Micro testing on a material that has low water content?
>I have received a material called Lauroyl macrogolglycerid into our Micro
>lab.  It is a waxy solid material. It is going into a solid oral dosage
>Additional information on this material : Prior to testing the material must
>be heated to 66 degree C overnight. An oven bath or oil bath is acceptable,
>a steam bath is not. The sample may be kept at this temperature for upto 72
>hours, stability at this condition
>has been established by the supplier.
>Do I have to screen for thermophilic organisms? But what is their clinical
>significance? From Dr. Cundell's article most of the organisms will not
>survive in products with water activity below 0.60.
>Please share your comments.

I agree with Richard Prince's recommendation not to test this material.

Holding a material with a low water activity at >60 degree C will not select
for thermophiles.

My colleague Bob Friedel is submitting a follow-up stimuli article
addressing the water activity of raw materials and a recommended Microbial
Limit testing strategy.

Tony Cundell
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