- Isolation Methods of pure cultures involves separating a single species of microorganism from a mixed population.
- Common methods include:

Streak Plate Method:
Pour Plate Method:
-
- Procedure: A diluted microbial sample is mixed with molten agar and poured into a Petri dish. After solidification, colonies develop both on and within the agar.
- Purpose: To isolate colonies from a mixed culture.
- Advantage: Useful for counting colonies and isolating pure cultures.
Advertisements
Spread Plate Method:
-
- Procedure: A diluted microbial sample is spread evenly across the surface of an agar plate using a sterile spreader.
- Purpose: To obtain isolated colonies.
- Advantage: Effective for quantifying and isolating microorganisms.
Serial Dilution:
- Procedure: The microbial sample is serially diluted in a series of dilution blanks, and aliquots from each dilution are plated.
- Purpose: To reduce the number of organisms and obtain isolated colonies.
- Advantage: Reduces the concentration of bacteria to isolate pure cultures