Koliformen

Koliformen, also known as coliform bacteria, are a broad group of bacteria that are commonly used as indicators of faecal contamination in water, food, and environmental samples. These bacteria belong to the family Enterobacteriaceae and are characterized by their ability to ferment lactose with the production of acid and gas within 48 hours at 35°C.

The most well-known coliform bacteria is Escherichia coli, which is specifically associated with fecal matter of warm-blooded animals. The presence of E. coli in water or food samples is generally considered a strong indicator of recent fecal contamination and the potential presence of pathogenic microorganisms. Other coliforms include species of Enterobacter, Klebsiella, and Citrobacter.

Detection of coliform bacteria is a common practice in water quality testing, especially for drinking water, recreational waters, and wastewater treatment. Standard methods involve taking a sample and incubating it in selective media that promote the growth of coliforms while inhibiting others. Results are typically reported as Most Probable Number (MPN) or colony-forming units (CFU) per 100 milliliters.

Although coliform bacteria themselves are usually harmless, their presence signifies a risk of pathogenic organisms such as Salmonella, Shigella, or viruses, which can cause illnesses ranging from gastrointestinal disturbances to severe infections. Therefore, monitoring coliform levels helps ensure water safety and public health.

Due to their ecological adaptability and ease of detection, coliform bacteria remain integral to environmental microbiology and water safety protocols worldwide.