CETRIMIDE AGAR BASE (Eur. Pharma.) 500 grams/bottle

Cetrimide Agar Base is recommended by the European Pharmacopoeia for the selective isolation and identification of Pseudomonas aeruginosa. This medium promotes the production of fluorescein (pyoverdin), a green-yellow fluorescent pigment that oxidizes to yellow. Fluorescein is not soluble in chloroform, unlike pyocyanin (blue-green pigment). The pigment diffuses throughout the medium and the fluorescent yellow-green color is observed. Strains of Pseudomonas aeruginosa are identified from specimens because, in addition to their colonial morphology and the characteristic grape-like odor of aminoacetophenone, they produce pyocyanin, a blue, water-soluble, nonfluorescent, phenazine pigment. P. aeruginosa is the only specie of Pseudomonas or Gram-negative rod known to excrete pyocyanin. Gelatin pancreatic digest provides nitrogen, vitamins, minerals and amino acids essential for growth. Glycerol is the carbon source. Magnesium chloride and Potassium Sulfate enhance the production of pyocyanin and pyoverdin. Cetrimide is the selective agent as it inhibits the growth of the accompanying microbial flora. The European Pharmacopoeia, USP recommends this media in the paragraph 2.6.13: "Microbiological examination of non-sterile products: Test for specified microorganisms" for the test of Pseudomonas aeruginosa in products.