Microbiology: Pour Plate Method Flashcards

Pour Plate Method Overview

• A technique for inoculating solid nutrient medium by mixing bacteria with melted agar.
• The mixture is poured into a Petri dish where it solidifies and is incubated for colony growth.

Required Materials

• Alcohol lamp
• Cotton swab applicator
• Lighter
• Masking tape
• Nutrient agar (NA)
• Sharpie
• Sterile Petri dish

Step-by-Step Procedure

• Obtain and keep a sterile Petri dish sealed to prevent contamination.
• Ignite the alcohol lamp using a lighter for sterilization.
• Sterilize the rim and cap of the nutrient agar bottle by passing through the alcohol flame.
• Pour melted nutrient agar into the sterile Petri dish.
• After pouring, sterilize the agar bottle and cap again with the alcohol flame.
• Collect swab samples while the agar solidifies.
• Once solidified, gently apply the sample onto the agar with the cotton swab in a back-and-forth motion.
• Label masking tape with the sample date, initials, type of agar, and sample location.
• Affix the labeled tape onto the lid of the Petri dish.
• Incubate the labeled Petri dish at 37°C for optimal bacterial growth.
• Retrieve the Petri dish post-incubation for observation.
• Examine the dish for bacterial colonies.
• Discard the Petri dish in a Biohazard Bin/Container after observations are completed.

Purpose of the Pour Plate Method

• This method allows for the quantification of colony-forming units (CFUs) in a sample for microbial analysis.