Mannitol salt agar (MSA) contains high levels of salt because it inhibits the growth of most bacteria. This makes it an excellent medium to test for Staphylococci and Micrococcaceae as they are tolerant of high levels of NaCl.
mannitol is a type of sugar, so it supplies the carbon in the MSA medium
Mannitol salt agar inoculated with Micrococcus luteusshowing no fermentation of mannitol (pink medium). The colonies show a yellow pigment which is characteristic of M. luteus.
Mannitol Salt Agar (MSA) is commonly used for isolating Staphylococcus aureus because it contains high salt concentration which inhibits the growth of many other bacteria while allowing the growth of Staphylococcus species. Additionally, the fermentation of mannitol by S. aureus produces yellow colonies on MSA, aiding in its identification.
Enterobacter aerogenes is not typically a salt-tolerant organism and would not be expected to grow well on Mannitol Salt Agar, which contains a high concentration of salt. This medium is more selective for salt-tolerant organisms like Staphylococcus species.
No, Salmonella Typhimurium cannot grow on Mannitol Salt Agar because it is a selective and differential media primarily used for isolating and differentiating Staphylococcus species based on their ability to ferment mannitol. Salmonella Typhimurium is not a mannitol fermenter, so it will not grow on this agar.
Mannitol Salt Agar Complex is a synthetic medium because it is prepared from pure chemical substances and the exact composition of the medium is known.
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Mannitol salt agar or MSA is a commonly used growth medium in microbiology. It contains a high concentration (~7.5%-10%) of salt (NaCl), making it selective for Staphylococci (and Micrococcaceae) since this level of NaCl is inhibitory to most other bacteria.
mannitol is a type of sugar, so it supplies the carbon in the MSA medium
mannitol is a type of sugar, so it supplies the carbon in the MSA medium
Mannitol salt agar supports growth of organisms that can grow in a high salt concentration, particularly Staphylococcus species and halophiles. The phenol red pH indicator in the agar will also let you know whether or not the bacterium you streaked ferments mannitol by changing to a yellow color if fermentation has occured.
Yes, Enterobacter cloacae typically cannot grow on mannitol salt agar because it does not ferment mannitol. Mannitol salt agar is selective for salt-tolerant Staphylococci species that can ferment mannitol, producing acid and turning the agar yellow.
Mannitol Salt Agar typically contains a high concentration of salt, which acts as the selective agent. This high salt concentration provides an environment that restricts the growth of many organisms, allowing only salt-tolerant bacteria such as Staphylococcus species to grow on the agar plate.
E. faecalis typically does not ferment mannitol, so it does not grow well on mannitol salt agar (MSA) and would not test positive on this medium. MSA is selective for organisms that can ferment mannitol, such as Staphylococcus species.
Bacillus subtilis typically does not ferment acid from mannitol salt agar as it lacks the enzymes needed for fermentation. Mannitol salt agar is mostly used to differentiate Staphylococcus species, which are capable of fermenting mannitol.
Mannitol salt agar inoculated with Micrococcus luteusshowing no fermentation of mannitol (pink medium). The colonies show a yellow pigment which is characteristic of M. luteus.
A concentration of 0.5-0.7% agar is typically used in semisolid medium for motility. This is lower than the typical 1.5-2% agar concentration used in solid medium, allowing motile bacteria to move more easily through the softer semisolid medium.