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which media for isolation of microorganisms from the environment? - (Apr/02/2014 )

Hello,
I wonder if anyone can suggest different media and growth conditions allowing the growth of most of the bacteria and fungi from the environment. Are there standard procedures to follow?
At the moment I'm using lb and Columbia agar containing sheep blood ?what else would you try to enhance the chance to isolate more species the surrounding of the microorganisms contains a lot of wax alcohols.
Thank you very much

-tretol-

Depends on what do you want to isolate and the source environment. All culture media will enrich in some species and not in others depending on growth rate, C and N sources,...

-El Crazy Xabi-

I assume that there is onlyoone species if any. The surrounding is waxy.I'm looking for a medium which is very rich and allows the growth of nearly everything :)

What does such a medium need? Yeast extract and bacto trayptone for nitrogen and amino acids,glucose for fermentation.I'll add sunflower oil and tween. What else could I use?

-tretol-

Only one species in what regard?

 

Doubtful that a medium exists allowing growth of "nearly everything."  Substantial soil microbial populations are not cultureable and others may be cultured but require, as El Crazy said, unique media.

 

Suggest you read the article linked below:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC546801/

-Phil Geis-

Even in those "weird" environments you will have more than one species. Though you may use more common culture media in later steps, I would suggest to mock that environment in a flask. I'm not sure about using oil, if you can use the same wax alcohols.

  • You may just collect some of that stuff an just place it in a flask in an orbital shaker at a temperature similar to that of the "environment" you get the samples and monitoring it for proliferation.
  • You may collect some of the aqueous phase (if it exists) and use it as base medium plus wax alcohols
  • You can analyse as much as you can that environment and make a synthetic version of what you find there. Don't forget the pH
  • You can use just a minimal mineral medium plus the wax alcohols as C-source (you may add Tween-80 or not)
  • You can increase the inoculum size by recovering part of the material by centrifugation. You may need to dissolve the waxy stuff with some surfactant
  • ...

Possibilities are nearly endless. Depending on what's your final goal, one approach may be more or less suitable

-El Crazy Xabi-

The excellent comments of El Crazy not withstanding, I strongly suggest you read the literature and understand what is known before jumping into uninformed experimentation.

-Phil Geis-

Thanks a lot I'll try both

-tretol-