5 replies to this topic

[badguy]

wat is the reason of using 2X LB, or 2X YT?

anyone can give a brief explanation?

i ask this question bcz i've seen ppl using 2x LB to prepare skimmed milk agar.

[leelee]

My guess would be that in order to have a 1x concentration of LB in the final agar, they need to use 2x (because they are adding the skim milk agar solution to it)?

[badguy]

leelee, on 09 February 2011 - 10:53 PM, said:

My guess would be that in order to have a 1x concentration of LB in the final agar, they need to use 2x (because they are adding the skim milk agar solution to it)?

i understand the skimmed milk agar part. but why wanna use 2X LB alone for bacteria culture.


as for the skimmed milk agar, skimmed milk powder cannot mix with the components of LB and autoclave together?

[pito]

I dont really understand what you mean... but do you mean 2X the normal concentration of LB?

Sometimes they state 2XLB,but they then dilute it so in the end its 1X ..

and why wouldnt you autoclace skimmed milk? There is no problem doing that...

[pDNA]

maybe it is due to the fact that more nutrients are available when using 2xLB?
the concentration of yeast extract and peptone does not really matter to cells i would assume ...NaCl does and you have to be carefull, 1% should be enough.

I never used 2xLB and i will not in future ...if you want fast growth and high cell densities use Terrific Broth (TB) instead!

Regards,
p

badguy, on 09 February 2011 - 10:27 PM, said:

wat is the reason of using 2X LB, or 2X YT?

anyone can give a brief explanation?

i ask this question bcz i've seen ppl using 2x LB to prepare skimmed milk agar.

[mdfenko]

badguy, i think you missed the point of leelee's response. what leelee was telling you is that 2x lb is a stock. when you add the components of the skim milk agar to the 2x lb (and adjust to final volume, if necessary) the concentration of lb in the agar will be 1x.