Technical Data
Simmons Citrate Agar (Powder)
Microbiological Grade
Storage RT/4C    Shipping RT
Formulation (g/L):
Ammonium Dihydrogen Phosphate1.0
Sodium Chloride5.0
Dipotassium Phosphate1.0
Magnesium Sulfate0.2
Bromthymol Blue0.08
Total 24.28g/L
The medium can be used to distinguish between E. coli and Enterobacter aerogenes and to assist in differentiating members of the Salmonella group. Organisms able to utilize the citrate grow well on the surface of the medium. Alkalinization the medium changing it from green to blue. If the organism cannot utilize the citrate, poor or no growth is shown and medium remains unchanged.

Microbiological Tests:
Enterobacter aerogenes ATCC 13048: Good Growth, Blue color

Escherichia coli ATCC 25922: Growth Inhibited, Green color

Salmonella choleraesuis ATCC 13076: Good Growth, Blue color

Salmonella typhimurium ATCC 14028: Good Growth, Blue color

Shigella flexneri ATCC 12022: Growth Inhibited, Green color

Formula per Liter:
Ammonium Dihydrogen Phosphate 1.0g
Sodium Chloride 5.0g
Dipotassium Phosphate 1.0g
Sodium Citrate 2.0g
Magnesium Sulfate 0.2g
Bromthymol Blue 0.08g
Agar 15.0g

Total 24.28g/L

Mix 24.2g of the medium in 1 Liter of dH2O until evenly dispersed. Heat while stirring, if necessary, to obtain solution. Distribute into test tubes. Autoclave at 121C for 15 minutes. After autoclaving, slant tubes to prepare deep butts.
Note: g/L may be adjusted or formula supplemented to obtain desired performance.

Directions per Liter: Dissolve 24.2g in 800-900ml of ddH2O stirring gently with heating until completely solubilized. Adjust pH of the medium to the desired level. Add additional water to bring the solution to 1L. Dispense into appropriate containers, loosen caps and autoclave for 15 minutes at 121C (15psi). After autoclaving, slant tubes to prepare deep butts.

Storage and Stability: Store powdered media at RT. Opened bottles should be capped tightly and kept in a dark, low humidity environment. Prepared media should be kept at 4C and used within a short period of time.

Appearance: Yellow with green tint, homogeneous, free flowing powder

Solubility: Forrest green, clear to turbid to clear.

pH (2.42%): 6.50.5


Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.