MICROBIOLOGY Study Guide - 2012

CHAPTER 14. SANITARY INDICATOR MICROORGANISMS

14.3. SULFITE-REDUCING CLOSTRIDIA

Sanitary indicator microorganisms include Bacteria of the species Clostridium perfringens, belonging to the family Bacillaceae. They are released into the environment with feces, but in significantly smaller numbers than coliforms and enterococci (105—106 Cells per 1 g).

Because clostridia of this species form spores, their detection in environmental objects and food products does not necessarily indicate recent fecal contamination. A distinctive feature of intestinal clostridia is their ability to reduce sulfites, whereas free-living clostridia lack sulfite reductase. This property forms the basis for identifying C. perfringens, which form black colonies on iron-sulfite Agar due to The production of FeS.

Quantitative enumeration of C. perfringens as a potential CAUSATIVE AGENT OF foodborne toxicoinfections is required when testing soil, medicinal muds, open-Water reservoirs, as well as meat and poultry products.



Last update: 13/08/2026

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