Mitis Salivarius Agar

Mitis Salivarius Agar

M

Mitis Salivarius Agar Tellurite Solution 1%
Intended Use
Mitis Salivarius Agar is used with Tellurite Solution 1% in isolating Streptococcus mitis, S. salivarius and enterococci, particularly from grossly contaminated specimens. and most gram-positive bacteria except streptococci. Trypan blue gives the colonies a blue color. Agar is the solidifying agent.Formulae
Difco™ Mitis Salivarius Agar
Approximate Formula* Per Liter Pancreatic Digest of Casein ........................................ 6.0 g Proteose Peptone No. 3 ............................................. 9.0 g Proteose Peptone ....................................................... 5.0 g Dextrose ..................................................................... 1.0 g Saccharose............................................................... 50.0 g Dipotassium Phosphate .............................................. 4.0 g Trypan Blue .............................................................. 75.0 mg Crystal Violet .............................................................. 0.8 mg Agar ......................................................................... 15.0 g

Summaryand Explanation
S. mitis, S. salivarius and Enterococcus species are part of the normal human flora. S. mitis and S. salivarius are known as viridans streptococci. These organisms play a role in cariogenesis and infective endocarditis and cause an increasing number of bacteremias.1 Enterococci cause urinary tract infections, wound infections and bacteremia.2 These organisms can colonize the skinand mucous membranes. Chapman3-5 investigated methods for isolating streptococci and formulated Mitis Salivarius Agar. The medium facilitates isolation of S. mitis (Streptococcus viridans), S. salivarius (nonhemolytic streptococci) and enterococci from mixed cultures.6

BBL™ Tellurite Solution 1%
Sterile 1% solution of Potassium Tellurite.
*Adjusted and/or supplemented as required to meetperformance criteria.

Directions for Preparation from Dehydrated Product
1. Suspend 90 g of the powder in 1 L of purified water. Mix thoroughly. 2. Heat with frequent agitation and boil for 1 minute to completely dissolve the powder. 3. Autoclave at 121°C for 15 minutes. Cool to 50-55°C.
Uninoculated Plate Enterococcus faecalis ATCC™ 19433

Principles of the Procedure
Mitis Salivarius Agarcontains peptones as sources of carbon, nitrogen, vitamins and minerals. Dextrose and saccharose are carbohydrate sources. Crystal violet and potassium tellurite (from Tellurite Solution 1%) inhibit most gram-negative bacilli

User Quality Control
Identity Specifications
Difco™ Mitis Salivarius Agar
Dehydrated Appearance: Solution: Bluish-beige, free-flowing, homogeneous. 9.0% solution, solublein purified water upon boiling. Solution is deep royal blue, very slightly opalescent. Deep royal blue, slightly opalescent. pH 7.0 ± 0.2 Colorless and clear to trace hazy.

Prepared Appearance: Reaction of 9.0% Solution at 25°C: Appearance:

BBL™ Tellurite Solution 1%

Cultural Response
Difco™ Mitis Salivarius Agar with BBL™ Tellurite Solution 1%
Prepare the complete medium per labeldirections. Inoculate and incubate under 5-10% CO2 at 35 ± 2°C for 18-48 hours.
ORGANISM ATCC™ INOCULUM CFU RECOVERY COLONY COLOR

Enterococcus faecalis Escherichia coli

Good Blue/black Partial to Brown, if any complete inhibition Staphylococcus aureus 25923 103 Partial to – complete inhibition Streptococcus mitis 9895 102-103 Good Blue Good Blue “gum Streptococcus salivarius 9758 102-103 drop”shape

19433 102-103 25922 103

Streptococcus salivarius ATCC™ 9758

369

Section III M Mitis Salivarius Agar, cont.

4. Add 1 mL of Tellurite Solution 1%. DO NOT HEAT THE COMPLETE MEDIUM. 5. Test samples of the finished product for performance using stable, typical control cultures.

Procedure
See appropriate references for specific procedures.

2. Molds will grow on the medium...