colony-forming unit

A colony-forming unit (CFU) is a scientific term used to estimate the number of viable bacteria or fungal cells in a sample. When microorganisms are cultured on a solid medium, each CFU represents a group of cells that originated from a single parent cell and grew into a visible cluster, or colony. CFUs are important in microbiology because they help researchers determine the concentration of living microbes in food, water, or clinical samples, providing insights into contamination levels or the effectiveness of treatments. Essentially, CFUs help measure how many living organisms are present in a given sample.