BLB agar is commonly used in microbiology for the selective isolation and differentiation of bacteria, particularly in clinical and environmental samples. It supports the growth of specific bacterial strains while inhibiting others through selective agents. One of its primary applications is in the detection of coliforms and enteric pathogens, where it helps distinguish between lactose-fermenting and non-lactose-fermenting organisms based on colony color. The medium is especially useful in water quality testing and food safety analysis to assess microbial contamination. Its formulation allows for easy identification of target bacteria, making it a valuable tool in diagnostic laboratories and public health monitoring.