Procedure is basically the same as for liquid media.
1. Flame needle.
2. Remove closure-flame tube.
3. Obtain small sample from stock culture.
4. Flame and close culture tube.
5. Return tube to rack.
6. Pick up sterile nutrient agar slant in left hand.
7. Remove closure-flame tube.
8. Gently streak sample from base of agar slant to the top in one continuous stroke. Do not chop up or dig into the agar.
9. Flame the tube and close.
10. Flame the needle.
IV. Pouring agar into Petri dish aseptically.
1. Place the three tubes of nutrient agar deeps into a water broth. A thermometer is necessary to measure water temperature-do not let it rest on bottom.
Be sure that the water level in the container is high enough to cover the agar in the tubes.
2. Bring the water to a boil. Agar liquefies at approximately 98 degrees Celsius. It solidifies at 42 degrees Celsius.
3. When agar has liquefied, remove the burner and allow the tubes to cool down in the water bath to about 50 degrees Celsius.
4. Remove tube-take off cap and pass mouth of tube through flame of Bunsen burner.
5. Lift top of Petri dish as illustrated and pour contents of the tube into sterile Petri dish.
6. Protect surface from contamination by holding cover above and replacing it immediately after pouring in the agar.
7. Swirl gently so that the agar is distributed evenly in the bottom of the plate. Allow the agar to solidify completely before proceeding. This should take only a few minutes. Surface should be even and firm-without lumps or cracks.
V. Streaking.
1. Using aseptic technique remove a small amount of the stock culture.
2. Lift the lid of the Petri dish-protecting the surface as much as possible from air contamination. Hold life just high enough to insert needle.
3. Place the culture (inoculums) on the agar surface at spot 1. Follow the diagrams of streaking illustrated-one...