Final answer:
Carbolfuchsin stain produces red acid-fast bacteria by binding to mycolic acid in the cell wall, a waxy substance that makes certain bacteria resistant to typical staining methods.
Step-by-step explanation:
The carbolfuchsin stain produces red acid-fast bacteria by binding to a component in the cell wall known as mycolic acid. Mycolic acid is a waxy substance that not only protects acid-fast bacteria like Mycobacterium and Nocardia from harsh environmental conditions but also makes them resistant to standard staining techniques such as the Gram stain. The acid-fast staining technique, which includes the Ziehl-Neelsen and Kinyoun methods, is used to identify these bacteria. It involves applying carbolfuchsin dye to a heat-fixed smear, which penetrates the waxy cell wall when heated, or without heat in the Kinyoun method.
Following staining, a decolorizer and then a counterstain are applied. Because of the presence of mycolic acid, acid-fast bacteria retain the red color of the carbolfuchsin stain even after the application of the decolorizing agent, which is usually an acid-alcohol solution.