This medium was developed by Blattner and colleagues as a rich medium for the propagation of bacteriophages. this medium provides all the amino acids, vitamins and other metabolites required for cell growth. NZCYM broth allows the cells to grow more rapidly as they do not have to synthesize nucleotide precursors and other factors required for growth. This media contains 0.7 % agar which functions as top agar for the propagation of lambda and filamentous phage.