In the news recently as a contaminant in one community's water supply in Ireland, Clostridium perfringens is widely distributed in the environment and is part of the normal flora in human and animal intestines. Since 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 & polymyxin to achieve selectivity, whilst cycloserine is used with the TSC formulation. Both OPSP and TSC combine sodium metabisulphite & ferric ammonium citrate to form the basis of the indicator system with which C. perfringens reduces sulphite, producing the black colonies synonymous with these media.