<span>Agar
is known to be a gelatinous polymer substance that was commonly used in the
laboratory setting as a substrate. Thus, nutrients agar can grow different types
of microbes such as fungi and bacteria while MacConkey agar is made with bile
salts and crystal violets, these additives cause the agar to only grow Gram –
negative bacteria. However, nutrients agars grow more organisms because it
contains nutrients from either beef broth or yeast extracts when compared with MacConkey
agar.</span>
