Pseudomonas Aeruginosa in bottled water
Hello.
Need your help.
I'm doing an investigation work in Angola, in a remote place. I came across this new bottled water company. They have a nice lab but lacks some material.
I was asked to help them.
The water pH is around 4,76 to 5,20...low EC (4 - 5 microS); no fecal coliforms; E.fecalis; but positive for P.aeruginosa.
Detection of P.aeruginosa was carried out using membrane filtration method and incubated in centrimide agar.
Then i realise that the CN culture media did not have or was not added the nalidixic acid.
.
The colonies that grow are small, not caracteristic of P.aeruginosa.
I do not have any confirmation test (oxidase test), only fluorescente lamps.
My question is what can i do? what other bacteria can grow in centrimide agar without nalidixic acid?
I attached pictures.
Thank you in advance.
Carina.20190720_151118.jpg 56.99KB 1 downloads
Hello.
Need your help.
I'm doing an investigation work in Angola, in a remote place. I came across this new bottled water company. They have a nice lab but lacks some material.
I was asked to help them.
The water pH is around 4,76 to 5,20...low EC (4 - 5 microS); no fecal coliforms; E.fecalis; but positive for P.aeruginosa.
Detection of P.aeruginosa was carried out using membrane filtration method and incubated in centrimide agar.
Then i realise that the CN culture media did not have or was not added the nalidixic acid.
.
The colonies that grow are small, not caracteristic of P.aeruginosa.
I do not have any confirmation test (oxidase test), only fluorescente lamps.
My question is what can i do? what other bacteria can grow in centrimide agar without nalidixic acid?
I attached pictures.
Thank you in advance.
Carina.
20190720_151118.jpg
Hi Carina,
Apparently, potentially, various species, eg I saw this quote for water analysis -
It was observed a moderate growth of E. coli, E. aerogenes and S. typhimurium in the m-Cetrimide medium (RGI < 10% in relation to the Triptone soy agar) while S.aureus, P. mirabilis and S. flexneri were inhibited (RGI < 0.001%). (RGI = relative growth index)
These results confirm that to achieve enough inhibitionin the m-Cetrimide medium, it is necessary to add different inhibitors, including antibiotics, such as nalidixic acid or fucidin and cephaloridine.
It is usually more advantageous to focus on confirmation (or not) as to whether the culture obtained matches the target species or not.
You will probably need to obtain some oxidase test strips , etc
also see -
Thank you very much.
I suspect that but i assumed that might be other Pseudomonas sp…
Will focus on confirmation test.
Kind regards
Thank you very much.
I suspect that but i assumed that might be other Pseudomonas sp…
Will focus on confirmation test.
Kind regards
I sympathise,
I have never worked with this species but the confirmation process in BAM looks quite lengthy.
Maybe iso's Procedure is simpler (often is).