Motility Test Medium

 Principle

• A mobility test medium is used to detect the mobility of microorganisms. The media is composed of peptone, sodium chloride, and agar. Peptone is a mixture of enzymically digested proteins used to promote the luxuriant growth of highly fastidious microorganisms and provides nitrogen and other necessary growth factors.
• The sodium chloride maintains the osmatic equilibrium of the medium. For mobility detection the media contain less concentration of agar, which makes it very soft and allows the mobile bacteria to migrate and cause cloudiness.
• The inoculum is stabbed into the center of a semisolid agar deep using a sterile inoculating needle. 
• The motile bacteria diffuse into the media and growth extending out from the line of inoculation. The dynamic motile organisms grow throughout the entire medium, whereas sluggish organisms show small areas or nodules that grow out from the line of inoculation.
• The non-motile bacteria only grow and show growth on the stab line where they are inoculated.

 Use: Recommended for testing bacterial mobility.