microbio medium/test pics

blood agar hemolysis

beta hemolysis. clearing around growth is a result of complete lysis of rbcs

blood agar hemolysis

alpha hemolysis. greenish zone around the colonies is a result of incomplete lysis of rbcs

blood agar hemolysis

gamma hemolysis. no hemolysis

blood agar hemolysis

aerobic vs anaerobic hemolysis. unidentified throat culture demonstrates alpha hemolysis on surface and beta hemolysis beneath the surface surrounding the arrow

positive CAMP test. arrowhead zone clearing in the region where CAMP factor of streptococcus

left

positive catalase test. staphylococcus aureus

right

negative catalase test. enterococcus faecium

left

positive catalase test. staphylococcus aureus

right

negative catalase result. enterococcus faecium

left

negative coagulase test. staphylococcus epidermidis

right

positive coagulase test. staphylococcus aureus

top

positive coagulase test. straphylococcus aureus

bottom

negative coagulase test. staphyloccus epidermis

kligler iron agar

all yellow = glucose and lactose fermentation, red slant / yellow butt = glucose fermentation, all red = no fermentation, black precipitate = sulfur reduction from glucose and lactose fermentation, cracks = gas production

optochin test

zone of inhibition around disk indicates susceptibility to optochin and a streptococcus pneumonia

oxidase test

oxidase positive = purple, oxidase negative = natural color

phenyltheyl alcohol agar

s. aureus and e. facieum grow because they are gram positive

hektoen enteric agar

E. coli produces yellow color because of the acid from lactose fermentation. p. mirabilis does not ferment but produce H2S

nekton enteric agar

salmonella = black colonies due to H2S reaction, E. coli = yellow due to lactose fermentation

eosin methylene blue agar

green / pink = coliforms

eosin methylene blue agar

dark centers = coliform

mannitol salt agar

yellow halo around s. aureus = mannitol fermentation