PCR quantitative in CFU/100 mL

The membrane filtration or culture-based method measures enterococci in water by counting live bacterial colonies. A measured amount of water is filtered through a special membrane that traps bacteria. The filter is placed on a nutrient-rich growth medium and incubated for 24 to 48 hours. Enterococci colonies grow and can be counted as visible spots. The result is reported in colony-forming units per 100 millilitres (CFU/100 mL), which indicates how many viable bacteria capable of forming colonies were present in the sample. This method is widely used for routine water quality testing, including beach safety and drinking water monitoring.