The steps involved in microbial strain isolation are as follows:
- Sample collection: The first step in microbial strain isolation is the collection of samples from the environment. The samples can be collected from soil, water, air, or any other source where microorganisms are likely to be present.
- Sample preparation: The collected sample is then prepared for microbial strain isolation. The sample is homogenized and diluted in order to reduce the number of non-target microorganisms.
- Inoculation: The prepared sample is then inoculated onto a selective or differential media to isolate the target microorganism. Selective media contain nutrients that only allow the growth of certain microorganisms, while differential media allow the differentiation of microorganisms based on their biochemical characteristics.
- Incubation: The inoculated media are then incubated under optimal growth conditions for the target microorganism.
- Colony isolation: After incubation, the colonies that grow on the media are isolated and purified. This is done to obtain a pure culture of the target microorganism.
- Strain confirmation: The isolated colonies are then identified to confirm the presence of the desired microbial strain. This can be done using various techniques such as microscopy, biochemical tests, and molecular techniques.
The presence of a particular strain can be confirmed by comparing the characteristics of the isolated strain with the known characteristics of the desired strain. For example, the morphology of the isolated strain can be compared with the known morphology of the desired strain. Similarly, biochemical tests can be used to compare the metabolic characteristics of the isolated strain with the known metabolic characteristics of the desired strain. Molecular techniques such as PCR and DNA sequencing can also be used to confirm the presence of specific genes or genetic markers that are unique to the desired strain.
