10.8: BAP Media Procedure

• 1 blood agar plate
• 3 stock plates
  • Stock plates will contain 1 of the following species: Escherichia coli, Bacillus subtilis, or Staphylococcus epidermidis 
• Sharpies
• Parafilm
• Inoculation loops or sterile cotton swabs 
• Incinerator 

Step 1: 

• Get into groups of 2. 
• Label the bottom of your blood agar plate with your initials, course section, and date.
• Using a sharpie, split the bottom of the agar plate into 3 sections and label each section with a different bacterial species. 

Step 2: 

• If using a sterile cotton swab, move to step 3. 
• Heat your inoculation loop in the incinerator for at least 10 seconds until the wire is red/orange. 
• Allow the loop to cool, but do not wave it around the air.
• You can test if the loop is cool by touching it to an area of agar that does not have bacteria and listening for a "sizzle" burning sound. 

Step 3: 

• Aseptically collect 1 colony from the stock plate. You do not need to swipe or gather a large amount of bacteria. 
• Partially remove the lid from your labeled sample plate, enough that you can reach the agar with the loop/swab while still shielding the plate.
• Gently touch the loop (or swab) to the agar and move it back and forth in a zig-zag motion over one-third of the plate.
• Be careful not to press too hard as you can cut or damage the agar. 
  • Make sure you are adding bacteria to the correctly labeled areas. 

Step 4: 

• Repeat Step 2 for the remaining bacterial species.
• Make sure you are sterilizing your loop between bacterial species.
  • If using sterile cotton swabs, make sure to obtain new swabs for each species. 
• Do not drag bacteria into the different labeled areas of agar. This is not a quad streak. 
• When you have inoculated all 3 bacterial species on 1 agar plate, seal your plate with parafilm and place it upside down in the 37°C incubator for 24 hours.