Used primarily in microbiology for the differentiation of enteric bacteria based on their ability to ferment carbohydrates and produce hydrogen sulfide. The medium contains glucose, lactose, and sucrose, allowing observation of fermentation patterns through pH indicators. It also detects hydrogen sulfide production, shown as blackening in the agar due to iron compound reduction. Commonly used in clinical labs to identify and distinguish members of the Enterobacteriaceae family, especially for presumptive identification of Salmonella and Shigella species. The slant and deep format enables both aerobic and anaerobic conditions in one tube, making it efficient for multiple biochemical tests simultaneously.