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Isolation and preservation method of pure culture
Isolation of pure culture
A culture media, which contain more than one kind of microorganism is called mixed culture media. A culture media that contain only one kind of microorganism is called a pure culture.
Isolation is the separating of particular microorganism from the mixed culture ‘or’ The transfer of bacteria from mixed culture to new sterile culture medium is called isolation of pure culture.
Advantage
1. The desired bacteria is obtain.
2. Bacteria get more nutrition and space for growth and development.
3. Easy in study.
Types of method of isolation of pure culture
The most commonly used method for pure culture:
1. Streak plate method:- In this method the bacteria are isolated from mixed culture by applying a streak on the surface of culture media. This is done by inoculation loop; the inoculation loop is heated in flame for sterilization and then streak on the surface of mixed culture after a streaky place the inoculation loop in new sterile culture media.
2. Pour plate method:- In this method, dilute agar solution (agar mix with some water) is mixed in the mixed culture media. Note, these dilute culture media after proper mixing, it transferred into Petri plates.
3. Spread plate method:- In this method, the culture medium is diluted with sterile saline solution. Now, take 1 ml of culture medium and placed on the surface of new sterile culture medium. Spread this drop with a glass spreader in all over the surface and allow to grow the bacteria.
4. Serial dilution method:- In this method, take five-seven test tube with filled 9ml of sterile distilled water(solution).
Now take 1ml solution from original suspension and diluted in 1st test tube, then take 1ml from 1st and diluted it in 2nd, then take from 2nd. Repeat this process until all test tube should be diluted. After diluted all tubes, take 1ml of each test tube and pour into nutrient agar plates.
As number of test tube increases, the concentration of bacteria is decreases and the dilution is increases. This method is used for actinomycetes bacteria.
Preservation method of pure culture
Preservation is a process to maintain pure culture for long period in viable condition. Once in any culture medium bacteria is grow then it placed for long time and there is lot of chances to be contaminated. The main objective of preservation to increase the viability of bacteria.
The preservation of pure culture can be achieved by following methods:
1. Subculturing:- In this method, the culture medium solution is regularly changed. In fresh culture medium the chances of contamination are less.
2. Storage in sterile condition:- In this method, calcium carbonate solution is added and the container is closed with cotton plug and place the under inoculator.
3. Refrigeration:- In this method, the culture medium is placed under refrigerator and add 02 to 4°C for 2 to 3 days. So, the microbes will kill.
4. Paraffin method:- In this method, paraffin oil added in the culture media, which inhibit the growth of bacteria because it forms a thin layer over the surface of culture medium.
5. Cryopreservation:- In this method, we put culture media at very low temperatures (-196°C), then all the microbes were killing by dehydration.
Isolation and preservation method of pure culture
Isolation and preservation method of pure cultures are essential for the successful use of microbes in research and industry. The process involves the selection, isolation and maintenance of a single species or strain from a complex mixture. This method is used to ensure that only one species or strain is present in the sample, allowing for accurate analysis and experimentation.
Isolation and preservation method of pure cultures involves several steps including enrichment, isolation, identification, and storage. These steps are designed to ensure that only one species or strain is present in the sample. This method also helps to preserve the integrity of the culture by preventing contamination with other organisms. By using this method, researchers can study a single organism under controlled conditions without interference from other organisms. Isolation and preservation method of pure culture, Isolation and preservation method of pure culture