SKU: sku-1769
For selective enrichment and enumeration of coliforms. It is recommended by BIS committee under specification IS:5887 (Part I and II) 1976, reaffirmed 2005.   MacCONKEY  BROTHW/ NEUTRAL  REDis  used  for selective  enrichment  and  enumeration  of coliforms. The  medium  contains  Peptic  digest  of  animal   tissue  which  provides  the  nitrogeneous  and    other    essential    growth    compounds.   Sodium  chloride  maintains  the  osmotic  balance  of the  cells. The selective action ofthese media is attributed to the presence of bile salts, which are inhibitory to most species  of  gram-positive  bacteria.Gram-negative  bacteria  usually  grow  well  on  these  media  and  are differentiated  by  their  ability  to  ferment  lactose.  Thecolour  change  of  the  medium  shown  by  lactose-fermenters is due to production of acid from lactose and a subsequentcolour change of the indicator dye when  the  pH  of  the  media  falls  below  6.8. Bile    salts    which    inhibits    the    growth    of    gram    positivemicroorganisms. The medium turns pink in case of lactosefermenters and yellow in case of non-lactose-fermenters,  due  to  neutral  red. Organism    producing    gas    can    be    observed    in    preparation    with  Durham  tubes. Inoculate  the  test  tubes  with  specimen, incubation  at  43 ±  1ºC  for  24-48  hours .The most probable number of coliforms per 100ml water is obtained from McGrady's tables. Confirmation of positive  results  is  carried  out  by  subculture  onto  solid  media  such  as  Endo  Agar  or  MacConkey Agar (without salt).
Product Code: 
TM 1238