Protocol Online logo
Top : Forum Archives: : Microbiology

Which media to choose to cultivate bacteria - (Nov/11/2007 )

Hi people,
Is LB agar specially used for cultivation of E coli only? Can't NA be used? I'm isolating bacteria from the environment and was wondering which of the two and why (the nutrients involved that separates the two).

Thanks

-jchchye-

QUOTE (jchchye @ Nov 11 2007, 05:32 PM)
Hi people,
Is LB agar specially used for cultivation of E coli only? Can't NA be used? I'm isolating bacteria from the environment and was wondering which of the two and why (the nutrients involved that separates the two).


Definitely depends of what you want from your environmental samples. Many bacteria won't grow on media like nutrient agar or LB and need richer media (like BHI). But many will and starting with such rich, non selective media might give you quite a lot of growth, and no way to recognize anything. Using a selected array of selective media will probably give you a much more interesting result.

-Canalon-

QUOTE (jchchye @ Nov 11 2007, 10:32 PM)
Hi people,
Is LB agar specially used for cultivation of E coli only? Can't NA be used? I'm isolating bacteria from the environment and was wondering which of the two and why (the nutrients involved that separates the two).

Thanks


LB was actually created and optimised to grow bacteria phage, hence the name "Lysogeny broth". And as already mentioned, LB is not rich enough or contains the required micro minerals and micro nutrient for many bacteria. LB is even contains growth inhibitory factors coming from the yeast extract and several that are produced during autoclaving (Millard reaction products) .

I would even say that LB isn't that great a medium to grow E coli, aside that LB has a nearly 60 years of tradition.

-perneseblue-