Growth Promotion Testing for New Recieved Lot of Media

Dear Forum Members

Once you have recieved any new lot of Media from approved vendor is it neccessary to certify that lot (what are the probable number of opening the lot from a hugh recipt of those lots) inspite of being procured from an approved vendor giving an COA and it is feasible to open and certify the new lot during routine testing of media.

Can this thinking pose any threat for bioburden testing, and sterility testing.

Any inputs with reference guidelines will be highly appreciated

Sameer Pandit.

Dear Sameer,

It is better to test the media not only for the compendial microorganisms but also for those specific microorganisms which have been recovered from past tests (e.g. a Sterility Test contaminant or a frequent environmental monitoring isolate). (For reference Pl. see FDA Guidelines on sterile drug produced by aseptic processing, PIC/S on sterile testing and USP chapter <71> and <1116>). You can also justify with the following statements

a.Can You say that the new batch of media is as good as a previously qualified batch? This question cannot be answered adequately except by statistical comparison, given the variability of microbio-logical data. So the best solution is to test the media.
b. There is no such media which could be non selective.All the media are selective although the level of selectivity is different.Therefore it is better to test the selectivity of media specially for the microorganism isolated from environment and as sterility test contaminants to avoid any false negative results.

According to my point of View, GPT Testing can be done concurrenlty while performing the sterility tests for a product, but there are other tests apart from Sterility My advice is to carry out GPT for TGM or TSB broth media Concurrently with sterility test and for other media we can set the frequency of testing for media based on lots and also time period.

There shouldnt be any problem.

Plz do correct me if i am misatken.



Dear Sameer,
(1) It is required to be tested the lot which is received from approved vendor for GPT. Also it is required that the lot is tested at regular intervals for GPT, if not consumed in time. Even the each batch of media prepared from that consignment has to be tested for GPT.
(2) Secondly as you asked about threat for bioburden & sterility testing : All the activities has to be carried out in GMP compliance facility with Good Microbiological Practices (GMP) in aseptic conditions. If such norms are followed there will not any threat about bioburden & sterility.
If you need further detail write to me at
(M) 09820389069

Dr.Pradeep Nagalkar
Head, Quality Control
Haffkine Bio-Pharma.Corpl.Ltd.

Can you plaese tell me about the neutralizer added to the media used for environment monitoring of Ceplasporin facility and what should be the quantity/concentration of that to the media.

I would think (I have no experience) that it would be ‘Nutrient Broth’ since Cyclosporine is known to kill/inhibit cell growth.