Letheen Broth Base is a liquid medium used to determine the antimicrobial activity of quaternary ammonium compounds. Based on Tryptone Glucose Extract (TGE) Agar, incorporation of Lecithin and Tween 80 results in the efficient neutralization of these compounds in disinfectants while testing germicidal activity. Enzymatic Digest of Casein and Yeast Extract supply amino acids, peptides, carbohydrates, vitamins and minerals. Sodium Chloride maintains the osmotic balance.