In the news recently as a contaminant in an Irish community’s water supply, Clostridium perfringens is widely distributed in the environment and is part of the normal flora in the human and animal intestine. As its spores can survive cooking and subsequently germinate to form vegetative cells, it is also an important cause of food poisoning.
Lab M’s Perfringens Agar OPSP is designed for the enumeration of C. perfringens in foods, and the company’s Perfringens Agar Base (TSC) is used in the preparation of tryptose sulphite cycloserine (TSC) agar for the enumeration and presumptive identification of the organism.
Perfringens Agar OPSP uses a combination of sulphadiazine, oleandoymcin and polymyxin to achieve selectivity, while cycloserine is used with the TSC formulation.
Both OPSP and TSC combine sodium metabisulphite and ferric ammonium citrate to form the basis of the indicator system with which C. perfringens reduces sulphite, producing the black colonies (see below) synonymous with these media.
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