October 25-27

Tasks for this week:
EMB Agar

Mannitol Salt Agar
MacConkey

RESULTS: 

EMB: Dark purple, green metallic sheen
Mannitol Salt Agar: Mannitol non-fermenter
MacConkey Agar: Lactose-fermenter

EMB

Purpose:

To isolate and differentiate gram-negative enteric bacilli

Materials:
EMB agar plate
Unknown "K" bacteria

Procedure:

Label EMB plate correctly. (See previous blogs)
Use aseptice technique to inoculate the EMB agar plate as a streak plate.
Incubate the inoculated plate upside-sown for 48 hours at 37 degrees C.
See results

Notice the green metallic sheen.

MANNITOL SALT AGAR

Purpose:

To isolate bacteria base don their salt tolerance and differentiate among these isolates for mannitol fermentation.


Materials:
Mannitol salt agar plateUnknown "K" bacteria

Procedure:

Label Mannitol plate correctly. (See previous blogs)
Use aseptice technique to inoculate the Mannitol agar plate as a streak plate.
Incubate the inoculated plate upside-sown for 48 hours at 37 degrees C.

Look at Results

Mannitol non-fermenter. Note, my bacteria is on the right side and it did not grow.

MacConkey Agar

Purpose:

To detect and differentiate among gram-negative enteric bacilli, based on their ability to grow on the medium and to ferment lactose. 


Materials:
MacConkey agar plate
Unknown "K" bacteria

Procedure:

Label MacConkey plate correctly. (See previous blogs)
Use aseptice technique to inoculate the MacConkey agar plate as a streak plate.
Incubate the inoculated plate upside-sown for 48 hours at 37 degrees C.
See results

Notice the bubbles coming from the bacteria. This occurred after applying Hydrogen Peroxide to the bacteria. This again proves that my bacteria is filtrated.

Lactose-fermenter