Culture Media

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Culture Media

                Culture media are required to grow the organisms from infected material to identify the causative agent.

    Basic constitvents of culture media are:

  •        Water
  •        Electrolyte
  •        Peptone
  •        Meat Extract
  •        Blood or Serum
  •        Agar

 

    Types of Media

1.               1. Based on physical state.

                  I.            Liquid Media

                II.            Semisolid Media

              III.            Solid Media

2.              2.   Based on presence of oxygen.

                  I.            Aeriobic

                 II.            Anaerobic

3.             3.  Based on nutritional factors.

                I.            Simple Media

              II.            Complex Media

             III.            Synthetic Media

             IV.            Special Media

 

     Special Media

  •         Enriched Media
  •         Enrichment Media
  •         Selective Media
  •        Differential Media
  •        Indicator Media
  •        Transport Media
  •         Sugar Media

 

    Simple Media

  •  Nutrient broth, Peptone water, Glucose Broth, Nutrient Agar.

          Complex Media

               vAll media other than simple media are complex media

               vIt has added ingredients.

          Synthetic Media

              Prepared from pure chemicals and Extract composition of the medium.

            Eg: Dubo's medium.

            Special Media

              a) Enriched Media:

  •      Basal medium is added with some nutrients such as blood, serum or egg.
        Blood Agar:
  •      Blood is added to the nutrient agar.
        Chocolate Agar:
  •      It is the heated blood agar.
        Loeffler's Serum Slope:
  •      Serum is added for enriching the medium.


         b) Enrichment Media:
               
                      Some substanceare in incorporated in the liquid medium which have a stimulating effect on the bacteria to be grown or inhibits the competitors.
        Eg.Selenite Broth.



         c) Selective Media:
            
                    Contains substance that inhibit all but a few types of bacteria and facilitate the isolation of a particular species.
            Eg. Bile Salt Agar.



         d) Defferential Media:
                
                    It contains substances which helps to distinguish differing characteristics of bacteria.
                Eg. Mac conkey's Medium.

         e) Indicator Media: 

                    It contains an indicator which changes color when bacterium grows in them.
                Eg. Mac conkey's Medium.



         f) Transport Media:

                    Used in case of delecate organisms.
                    Transport of specimens to the laboratory.
                Eg.Stuart's Transport Medium.




         Anaerobic Culture Media:

                     It is used for cultivation of aerobic bacteria.
                Eg. Cooked Meat Broth (CMB.)




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