Common Microbiological Media for Aerobic Cultures

Most aerobic species of bacteria (those that can grow in the ambient 20% O2 found in earth's atmosphere), will grow on one or more of the media types below.

Solid media commonly contain 1.5% agar per weight to solidify the liquid, nutrient part of the media. After sterilization, the liquid media is poured into sterile Petrie plates - think of it along the lines of pouring heated jellow into small cylindrical molds.. Petrie plates are commonly made of plastic, and can be purchased already sterlilzed with 25 or more per package.

Luria Bertani Broth (LB)	LB-Agar	MacConkey Agar	Sheep's Blood Agar	Chocolate Agar	Hektoen Enteric Agar

Uses: Culture of aerobic bacterial species	Uses: Culture of aerobic bacterial species on solid media	Uses: Selective media for Gram-negative, enteric bacteria (bile tolerant). Assess lactose fermentation	Uses: Non-selective media, good for culturing many bacterial species including Gram negative and Gram-positive species including Staphylococci and Streptococci	Uses: Very enriched media with lysed red cells, to release many nutrients needed by fastidious organisms. It may look like chocolate, but would have a rather nasty flavor, like coagulated blood-flavored jello..	Uses: Selective media for Gram-negative enteric bacteria (higher bile salt concentrations than MacConkey). Used to assess lactose fermentation AND ability to produce hydrogen sulfide (H2S). Allows for distinguishing among, E. coli, Salmonella and other gut pathogens including Shigella species
Recipe: 10g Tryptone 5g Yeast Extract 10g NaCl 1L distilled water pH to ~7.3-7.5. Distribute 5-10mL into glass tubes with autoclavable tops. Autoclave 30 minutes, OR place in a pressure cooker for ~45 minutes @ 15 pounds pressure.	Same as for LB-broth, but add 15g of agar prior to autoclaving. Be certain to mix thoroughly prior to pouring media into Petrie plates.	Recipe: 10g lactose 20g peptone 5g bile salts "pinch" or small amount of 1mg/mL Bromcresol purple or Crystal violet solution. 15g agar 1L distilled water	Recipe: 5% anticoagulated Sheep's blood Tryptose Soy nutrient agar base (contains agar in it). 1L of water	Recipe: Recommend commerically produced media.	Recipe: Recommend commercially produced media. If bought in powder form, must heat over heating plate prior to pouring plates. Do not autoclave.