EMB AGAR (LEVINE)

SKU: sku-150
Description: 
For isolation, enumeration and differentiation of members of Enterobacteriaceae. EMB  AGAR  or  EOSIN  METHYLENE  BLUE  AGAR,  LEVINE is used for isolation, enumeration and differentiation  of  Enterobacteriaceae.  This  dehydrated  medium  is  irradiated  with  dosage  **25  kGy  – 68kGy which is sufficient and adequate to eliminate sterility assurance level (SAL) of 10-6 (10-12). Whereas, a minimum dose of 25 kGy is desired for microbial control or sterilization10. First EMB was introduced by Holt - Harris and Teague in 1916 to differentiate Escherichia spp. and Aerobacterspp. Later, modified by Levine  in  1918  who  has  increased  the  Lactose  content  by  removing  Sucrose  from  the  formula.  The medium  contains  Peptic  digest  of  animal  tissue  source  of  carbon  and  nitrogen  for  the  growth  of microorganisms. Lactose is the fermentable carbohydrates. Differentiation of enteric bacteria is possible due to the presence of the sugars lactose in the EMB agar and the ability of certain bacteria to ferment lactose in the medium. Lactose-fermenting gram-negative bacteria (generally enteric) acidify the medium, and under acidic conditions the dyes produce a dark purple complex which is usually associated with a green metallic sheen.  Dipotassium phosphate is the buffer. Eosin Y and Methylene blue are dyes that combine to form a complex at an acid pH. Small amounts of this dye effectively inhibit the growth of most gram-positive bacteria. Eosin is a dye that responds to changes in pH, going from colorless to black under  acidic  conditions.  At  a  sufficiently  low  pH, strong  lactose  fermenters  such  as Escherichia  coliproduce colonies with a green metallic sheen. This metallic green sheen is an indicator of vigorous lactose fermentation ability typical of fecal coliforms. A smaller amount of acid production, which is a result of slow  fermentation  (by  slow  lactose-fermenting  organisms),  gives  a  brown-pink  coloration  of  growth. Colonies of non-lactose fermenters appear as translucent or pink. Agar is the solidifying agent.
Product Code: 
TSM 371
Technical Data: