1. EMB (which is Eosin methylene blue which is a selective stain for gramnegative bacteria. EMB contains dyes that are toxic to gram-positive
bacteria).
... [Show More] This agar is a dark red color, almost burgundy. This plate had a
lot of condensation in it, so I wiped the lid with a kimwipe before doing my
quad streak.
2. MAC (MacConkey agar is an indicator, a selective and differential culture
medium for bacteria, designed to selectively isolate Gram-negative and
enteric bacilli and differentiate them based on lactose fermentation). This
agar is a pale red, almost like a darker pink. This plate had a lot of
condensation in it, so I wiped the lid with a kimwipe before doing my quad
streak.
2
3. PEA (Phenylethyl alcohol agar is a selective medium that permits the
growth of gram-positive cocci while inhibiting most gram-negative
organisms.) This agar is clear colored. This plate had a lot of condensation
in it, so I wiped the lid with a kimwipe before doing my quad streak.
4. MSA (Mannitol Salt Agar is a selective and differential medium. The high
concentration of salt selects for members of the genus Staphylococcus,
since they can tolerate high saline levels. Organisms from other genera
may grow, but they typically grow very weakly). This agar is a pink color.
5. TSA (Trypticase soy agar is a general-purpose, nonselective media
providing enough nutrients to allow for a wide variety of microorganisms to
grow). This is a clear to pale yellow colored agar.
6. NA (is usually used for growth of nonfastidious organisms and observation
of pigment production). This is a light to pale yellow colored agar.
I then made two gram stains from my unknown mixture and viewed them under
the microscope. My gram stain showed that I had a Gram negative bacillus and a Gram
positive bacillus. I know this because I had clear view of purple rods mixed with pink
rods. The purple color is for positive and the pink is for negative. I kept one of the slides
as my confirmatory gram stain, and placed it in my slide case, and then disposed of the
other in the glass biohazard container. [Show Less]