ANTIBIOTIC MEDIUM Nº 1 (SEED AGAR) 500 grams/bottle

Antibiotic Medium Nº 1 is the standard agar base used for the microbiological assay of antibiotics like neomycin and erythromycin. The activity (potency) of an antibiotic can be demonstrated under suitable conditions by its inhibitory effect on microorganisms. Reduction in antimicrobial activity may reveal changes not demonstrated by chemical methods. The antibiotic media are identified numerically with names assigned by Grove and Randall in Assay methods of antibiotics. The use of standardized culture media and strict control of all test conditions are essential requirements in the microbiological assay of antibiotics in order to obtain satisfactory test results. This medium is recommended by USP and the european pharmacopoeia. Neomycin assay is carried out using the cylinder plate method. This medium has the same formula as Antibiotic Medium Nº 11 (Cat. 1528), with the difference that the pH of the medium has been adjusted to 6,6. A medium with a higher pH and the same formula is used for the assay of erythromycin, carbomycin and neomycin.