I wanted to isolate slow growing bacteria from environmental sample but LB is giving only few bacteria which has high doubling time.
Jai,
What kind of bacteria do you want to isolate?
Where are two main ways: 1) use general medium like YDC with /without enrichment in liquid medium, or 2) use selective medium with antibiotic and other selective bactericides.
Alex
Hello,
If we take the example of filamentous actinobacteria, they tend to have a slowly growth in comparaison with the non-filamentous ones and the firmicutes. Therefor, their isolation requires the use of several antibacterial and/or antifungal selective agents to exclude the invasive bacteria and fungi so they can't grow on the selective medium. Otherwise, you can add to the selective medium a specific substrate that can be used by few kinds of bacteria, including the one that you desire to isolate. In the case of filamentous actinobacteria, it is recomended the use of chitine or humic acid in the selective medium.
Best regards,
Hello,
I agree with coleauges above. Please provide more information which microorganisms you are willing to culture. It is important because you should adjust the environment, media composition and even thickness of agar. Another thing is that you may need Petri dishes without 'vents' which should keep water inside plate. For environmental microorganism the Starch Casein Agar is quite good, but if you want to keep your plates longer it is advisable to inhibit funghi by addition of cycloheximide to medium. Concentration of cycloheximide shouldn't exceed 100 mg/L. In some cases you will need to add e.g., aminoacids (like cysteine). If you would like to culture only Gram positive bacteria increase concentration of NaCl in your medium. In case when you would like to culture Gram-negative, then add sodium deoxycholate. Of course what I have written is only tiny example of modifications you may need. For environmental samples this has great importance because of huge biodiversity of such material.
Hello, I agree with colleagues above. How kinds of microorganisms are you willing to culture? It is important because you should know the environment, to choose media composition and even thickness of agar. For environmental microorganism the Starch Casein Agar or Nutrient agar are quite good. For environmental samples this has Great importance because of huge biodiversity of such material.
If the proposed organism is fastidious in nature, then an appropriate axenic culturing is the best way to cultivate the isolates. Provide the culture with optimum atmosphere, temperature, growth inhibitors and growth promoting factors in favour to the proposed organism. Meanwhile, you need to give more information on the organism.
Check here for more information: cmr.asm.org/content/28/1/208.full
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