EMB- Eosin Methylene Blue Test Flashcards
Purpose of EMB test
distinguishes bacteria that FERMENT LACTOSE (E.Coli ) from other gram negative bacterias that DO NOT FERMENT LACTOSE
IF EMB test is positive , what color will it be?
Green is positive for presence of E. COli
to ferment =
to breakdown
If EMB test is negative, what color will it be?
Negative EMB test will be pink/purple ;
Positive EMB tests are green because?
The bacteria was able to ferment lactose and produce an acidic waste product thats sucks up blue dye and causes a color change
Negative EMB tests are pink/purple because?
Bacteria was not able to ferment lactose. Instead it broke down proteins and produced alkaline waste product that strengthens bacteria cell wall & no dye is taken up.
example of positive EMB test bacteria
E.coli
example of negative EMB test bacteria
Salmonella
EMB test can also be used to distinguish between these forms of bacteria
coliform vs non coliform
EMB test encourages growth of gram negative bacteria because its dyes are ____ to gram positive bacteria??
toxic
ph indicators; nutrients
Eosin Y & Methylene Blue; Sucrose and lactose