Petri dish culture

• Preparing a petri dish culture

  1. Sterilise all petri dishes, nutrient broth and agar

  2. Sterilise inoculating loop by sterilising it on Bunsen flame

  3. Use inoculating loop to transfer bacteria onto the petri dish

  4. Attach lid of petri dish with adhesive tape

  5. Place agar plate into an incubator upside down
• Incubation temperature


  25°C - reduces the chance harmful bacteria will grow
• Preparing an agar plate for antibiotic testing

  1. Clean bench with disinfectant solution

  2. Sterilise an inoculating loop by passing it through a Bunsen burner flame

  3. Open a sterile agar plate next to a Bunsen burner

  4. Use the inoculating loop to spread bacteria evenly over the plate

  5. Place sterile filter paper discs containing antibiotics onto the plate

  6. Incubate at 25°C for a few days
• Zone of inhibition

  The area around the antibiotic discs where bacteria has not grown