Chapman formulated mannitol salt agar to isolate staphylococci by inhibiting growth of most other bacteria with a high salt concentration. Remel mannitol salt agar is a solid medium recommended for use in qualitative procedures for selective and. So it is used for isolating staphylococci bacteria. Mannitol salt agar msa is used as a selective and differential. English description mannitol salt agar is a selective medium used for isolating pathogenic staphylococci from clinical samples, food and other materials of sanitary importance.
Mannitol is a naturally occurring alcohol found in fruits and vegetables and used as an osmotic diuretic. The high level of sodium chloride inhibits most other organisms and as most staphylococcus aureus ferment mannitol the inclusion of phenol red indicator gives rise to yellow colonies. Mannitol salt agar msa is recommended by the american public health association for the enumeration of staphylococci in food and dairy products. Pp0660 mannitol salt agar usp a selective medium for the isolation of staphylococcus aureus. Mannitol salt agar is selective as well as differential. Mannitol salt agar was evaluated for detection of oxacillin resistance in 6 staphylococcus aureus isolates. An increase in osmolarity limits tubular reabsorption of water and inhibits the. Mannitol salt agar is a nutritive medium due to its content of peptones and beef extract, which supply essential growth factors, such as nitrogen, carbon, sulfur and trace nutrients. Mannitol and salt have often been combined as an aid in identification and a selective agent, respectively. Hydrogen peroxide is the testing agent for the catalase test, if the bacterium bubbles. Formula adjusted, standardized to suit performance parameters. Performance characteristics and limitations of the procedure bd mannitol salt agar with oxacillin is used for the isolation of methicillin resistant staphylococcus aureus mrsa from clinical specimens.
Mannitol salt agar is a nutrient agar to which has been added 7. Mannitol salt agar is best prepared from ready to use dehydrated powder, available from most suppliers of culture media. The medium is usually used at a concentration of 11. The ph indicator in mannitol salt agar is phenol red, which turns to yellow when the medium is acidified by the products of fermentation. It is selective because, this growth medium contains a good amount of salt, thereby inhibiting the growth of almost all bacteria, except those in the genus staphylococcus. Several different bacteria were plated, but only the halophiles grew. Mannitol salt agar msa chapman medium for the isolation and enumeration of pathogenic staphylococci from clinical samples and other materials product description name. Mannitol salt agar msa is a selective medium prepared according to the. Mannitol salt agar for the isolation of staphylococcus aureus. Mannitol salt agarcefoxitin combination as a screening.
Mannitol is freely filtered by the glomerulus and poorly reabsorbed from the renal tubule, thereby causing an increase in osmolarity of the glomerular filtrate. Presumptively detect, isolate and enumerate pathogenic staphylococci in milk, food, fish and other specimens with thermo scientific oxoid mannitol salt agar dehydrated. It is autoclaved and dispensed into sterile petri plates. Mannitol salt agar msa for the identification of staphylococcus. Mannitol salt agar with 1 mgliter oxacillin was shown to have a sensitivity of 90. Presumptively detect, isolate and enumerate pathogenic staphylococci in milk, food, fish and other specimens with thermo scientific oxoid mannitol salt. Mannitol salt agar article about mannitol salt agar by. Following vortex extraction in 2 ml of sterile saline, each was streaked for isolation on blood agar growth control and on mannitol salt agar msa and incubated at 37degreesc for 2448 hours. The results shown on day five that the agar had turned yellow indicating a positive for this test.
Hardy diagnostics mannitol salt agar msa is recommended for use as a selective and differential medium for the isolation of pathogenic staphylococci. Mannitol salt agar contains peptones and beef extract, which supply nitrogen, vitamins, minerals and amino acids essential for growth. The medium conforms to the requirements of the harmonised uspepjp. Mannitol salt agar is selective medium for the isolation of pathogenic staphylococci. All mecapositive isolates n 54 were correctly categorized as oxacillin resistant by the disk diffusion test 1. Beef extract 1gl, pancreatic digest of casein 5gl, peptic digest of animal tissue 5gl, sodium chloride 75gl, dmannitol 10gl, phenol red 0. Mannitol salt agar selective medium for isolation and enumeration of staphylococci from clinical samples and other materials, according to uspepjp. Mannitol salt agar is used as a selective media for the isolation of pathogenic staphylococci.
Chapman showed that adding a high level of sodium chloride to phenol red mannitol agar allowed for the recovery of pathogenic staphylococci. Pm30 our mannitol salt agar is a selective medium used for the differential isolation of staphylococci. Use of mannitol and salt resistance this medium has a 2fold purposesalt resistance and mannitol sugar use. Mannitol salt agar is used for the isolation of staphylococci in a laboratory setting. Mannitol salt agar dehydrated thermo fisher scientific. The resulting mannitol salt agar base is recommended for the isolation of coagulasepositive staphylococci from cosmetics, milk, food and other specimens 10.
Mannitol salt broth is prepared as suggested by chapman 3 and is used for the selective isolation of pathogenic staphylococci. Isolation and differentiation of staphylococcus aureus. It encourages the growth of a group of certain bacteria while inhibiting the growth of others. The bacteria grew on mannitol salt agar fermenting mannitol, as shown by the change to yellow of the medium. Dnase and mannitol salt agar improve the efficiency of the. Sodium chloride also supplies essential electrolytes for transport and.
This medium is recommended for the detection and enumeration of coagulasepositive staphylococci in milk 7 food 2 and other specimens. Composition ingredients gms litre proteose peptone 10. Pathogenic staphylococci produced yellow colonies whereas nonpathogenic staphylococci produced. Mannitol salt agar is 3 used for isolating staphylococci from clinical specimens,2 from cosmetics, and in microbial limit tests. Mannitol salt agar intended use remel mannitol salt agar is a solid medium recommended for use in qualitative procedures for selective and differential isolation of staphylococci. The resulting mannitol salt agar base is recommended for the. Mannitol salt agar msa culture media online microbiology notes. If the specimen to be cultured is on a swab, roll the swab over a small area of the. Mannitol salt agar or msa is a commonly used selective and differential growth medium in. Isolation and presumptive identification of staphylococcus aureus in nonsterile pharmaceuticals and food packaging. Adjusted andor supplemented as required to meet performance criteria.