Product Code TM 2247
Description
Bacterial motility can be observed directly on microscopic slide or it can be visualized on motility media having agar concentration of 0.4% or less. Use of such semisolid media to observe or detect motility was reported by Tittsler and Sandholzer. Motility Test Medium is the modification of the original formulation as per Edwards and Ewing and is used for testing motility of Enterobacteriaceae. Motility can be visualized as a diffused zone of growth flaring out from the line of inoculation.
Bacterial motility can be observed directly by examination of the tubes following incubation. Inoculation is done by stabbing through the centre of the medium. Incubate at appropriate temperature for 18 to 40 hours. Non-motile organisms grow only along the line of inoculation whereas motile organisms grow away from the line of inoculation or may show growth even throughout the medium. All weak or equivocal motility results should be confirmed by flagellum stain or by direct wet microscopy (hanging drop). To enhance the visibility of bacterial growth 2,3,5 Triphenyl Tetrazolium Chloride (TTC) may be added. Tetrazolium salts are colourless but are converted into insoluble formazan, a red coloured complex by the reducing properties of growing bacteria. In Motility Test Medium containing tetrazolium, the development of this red colour helps to trace the spread of bacteria from the inoculation line. The motility of Listeria monocytogenes is frequently best observed in medium without TTC.
Principle
for testing motility of enteric bacteria
Microorganism
Industry
Pack Size
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