Nutrient agar

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Streak plates of several bacterial species on nutrient agar plates K pneumoniae M morganii providencia styphimuriuma.JPG
Streak plates of several bacterial species on nutrient agar plates

Nutrient agar is a general-purpose solid medium supporting growth of a wide range of non-fastidious organisms. It typically contains (mass/volume): [1]

Contents

Nutrient broth has the same composition,
but lacks agar. [2] [3]

These ingredients are combined and boiled for approximately one minute to ensure they are mixed and then sterilized by autoclaving, typically at 121 °C (250 °F) for 15 minutes. Then they are cooled to around 50 °C (122 °F) and poured into Petri dishes which are covered immediately. Once the dishes hold solidified agar, they are stored upside down and are often refrigerated until used. Inoculation takes place on warm dishes rather than cool ones: if refrigerated for storage, the dishes must be rewarmed to room temperature prior to inoculation.[ citation needed ]

See also

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References

  1. American Public Health Association, American Chemical Society, Association of Official Agricultural Chemists (1920). Standard Methods for the Examination of Water and Sewage. American public health association. pp.  95.{{cite book}}: CS1 maint: multiple names: authors list (link)
  2. Nutrient broth - Bugwoodwiki . Retrieved 2022-08-13.{{cite encyclopedia}}: |website= ignored (help)
  3. Fahy, P. C.; Persley, G. J. (1983). Plant Bacterial Diseases: A Diagnostic Guide. Academic Press. ISBN   9781224766033. OCLC   10249741.

Further reading