Table of Contents
Brucella Blood Agar
It is one of the pre-reduced anaerobically sterilized plated medium used for cultivation, quantification and partial recognition of some of the obligate anaerobic bacteria collected from some clinical specimens. This medium also supports the growth of some of the anaerobic and microaerobic. It contains hemin, sheep blood and vitamin K1.
Tryptic Soy Blood Agar
Tryptic soy blood agar is another differential medium that has been pre-reduced anaerobically and is used for isolation and cultivation of some of the fastidious and non-fastidious microorganisms. It mainly contains some sheep blood for haemolytic reactions.
Mannitol Salt Agar
It is used for isolation of pathogenic Staphylococci. It consists of mannitol, 7.5% sodium chloride and phenol red indicator. Because of the high concentration of salt, most of the microorganisms are inhibited to grow other than Staphylococci. It is because most of the bacteria other than Staphylococcus are halophilic and do not grow in a high concentration of salt.
Mannitol fermentation is observed in pathogenic Staphylococcus series and is indicated by the presence of acidic products in the media thereby making phenol red present in the media to change from red-orange to bright yellow in colour. In this medium, the pathogenic Staphylococci form tiny colonies that are surrounded by yellow zones. It occurs because S. aureus causes fermentation of mannitol thereby producing an acid that changes the colour of the indicator from red colour to yellow colour.
