Muramic acid is primarily used in the field of microbiology and biochemistry as a marker for bacterial cell walls. It helps in identifying and quantifying bacterial biomass in environmental samples, such as soil or water. This is particularly useful in studies related to microbial ecology and environmental monitoring. Additionally, muramic acid is employed in research to understand bacterial cell wall synthesis and degradation, which can aid in the development of antibiotics and other antimicrobial agents. Its detection in clinical samples can also assist in diagnosing bacterial infections, especially in cases where traditional methods may be inconclusive.