Explain the Procedure for Preparation of General Purpose Media

Procedure: Now prepare the media following the steps enumerated herewith:

1. Weigh and dissolve each ingredient except agar in 500 ml of distilled water.

2. Make the volume to 1000 ml with distilled water. Set the pH to 7.0. This is a nutrient broth.

3. Autoclave the nutrient broth and dispense in sterile test tubes aseptically.

4. For nutrient agar, add 15 gms of agar in 1000 ml of nutrient broth. Heat the mixture to dissolve agar.

5. Dispense the mixture into flasks and autoclave at 15 psi for 15-20 minutes.

6. After autoclaving, cool the nutrient agar medium to 45°C and dispense it aseptically into sterile petri plates and tubes to make agar plates, slants and deep tubes.

7. Allow to solidify. For making slants, keep the tubes in inclined position for agar solidification.

8. Inoculate nutrient agar plates and tubes and nutrient broth with bacterial culture and incubate for 24 hours.

9. Note the observations and results.