Of course you can. That is the intended function of this medium that is both differential (mannitol fermentation) and selective (7.5% salt content). Staphylococci are readily cultured and S. aureus is indicated by mannitol fermentation.
http://www.microbelibrary.org/component/resource/laboratory-test/3035-mannitol-salt-agar
Hi Rene Christena,
Koch reported the use of a medium containing 7.5% sodium chloride as a selective agent for the isolation of staphylococci in 1942. The results were confirmed and improved by Chapman in 1945 by the addition of this salt concentration to Phenol Red Mannitol Agar. Staphylococcus aureus usually ferments mannitol. Non-pathogenic staphylococci usually show less luxuriant growth on this medium after the incubation period. Staphylococcus aureus produces small colonies surrounded by yellow zones. The reason for this change in color is that S. aureus ferments the mannitol, producing an acid, which changes the indicator from red to yellow. Those staphylococci that do not ferment mannitol show a purple or red zone around the colonies.
Yes, you can use this agar. Is a selective medium for the isolation of pathogenic staphylococci from clinical specimens and biological and pharmaceutical products. The beef extract and peptone are special sources of nitrogen, carbon, sulfur and other factors necessary for growth. The concentration of 7.5% sodium chloride determines a complete inhibition of bacteria other than staphylococci. The mannitol fermentation is indicated by phenol red tone and differentiation staphylococcal strains.
S. aureus = yellow colonies
Yes. It does not only support the growth of S. aureus but also makes it very easy to identify the organism on it especially because the agar supports the growth of other species of Staphylococcus species. This presence of this organism causes the red colour of the medium to change to yellow.
Yes the strains of S. aureus grow on maninitol salt agar and is a test that makes identification possible
Yes you can use this selectif medium, that's wich we use in our laboratory to isolate pathogenic staph in biologicals samples.
Thanks patrick,
Even i have 2 clinical isolates of S aureus out of which one seems to grow but the other does not so i was a bit confused.
Biochemically there is always a small percentage of the species to be exceptional (example S. Paratyphi A spp. app. 1% could be H2S positive, similarly app. 1% S. Typhi could be totally H2S negative).
So its possible to get non-yellow S. aureus on MSA.
On BPA (Baird Parker) CoNS could be smaller black colonies compared to S. aureus. BPA is preferred/ used mainly by food Microbiologists.
I agree with you Patrick.
You were fortunate to follow foot steps of of Anthony Baird-Parker.
Apart from s aureus, what other types of microorganisms can grow on baird parker agar?
Sir, what are the characteristics for specifically identifying these colonies?
Is there any gram negative species that is able to grow and ferment on Mannitol salt agar?
Harleen. As NaCl (7.5%) is the selective mechanism and there a re many halophilic/tolerant Gram negative bacteria and mannitol fermentation is not that rare a capability, it is possible. http://www.microbiologyresearch.org/docserver/fulltext/micro/128/9/mic-128-9-1959.pdf?expires=1452367626&id=id&accname=guest&checksum=6B379CE203DB25353116716EA2D2E6CE
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