Mannitol Salt Agar (7143)

Intended Use

Mannitol Salt Agar is specifically designed for the isolation and differentiation of staphylococci. It conforms to Harmonized USP/EP/JP requirements, ensuring its reliability in laboratory settings.

Product Summary and Explanation

Formulated by Chapman, Mannitol Salt Agar effectively isolates staphylococci by using a high salt concentration to inhibit the growth of most other bacteria. The medium contains 7.5% Sodium Chloride added to Phenol Red Mannitol Agar. This unique formulation enables coagulase-positive staphylococci (pathogenic strains) to thrive, leading to the development of distinctive yellow colonies that create noticeable yellow zones around them. In contrast, nonpathogenic staphylococci will produce small red colonies without altering the surrounding medium’s color.

This agar is highly selective; thus, it allows for the streaking of specimens from heavily contaminated sources without the risk of overgrowth. Mannitol Salt Agar is recommended not only for isolating pathogenic staphylococci from clinical specimens but also for analyzing cosmetics and conducting microbial limit tests.