Team:TU Darmstadt/Materials/LB

LB

Luria-Bertani Medium (aka LB medium) is one of the most common used standard growth medium for a variety of bacteria.

Ingredients

For 1L:

1. 10 g tryptone
2. 5 g yeast extract
3. 10 g NaCl

For plates add:

1. 15g agar (according for a volume of 1L)

Protocol

For medium

1. Mix dry ingredients and add dH₂Oup to 999 mL
2. Adjust the pH to 7.0 add the missing amount of water to 1L (5M NaOH works best with small voluminas)
3. Pour the mix into a 2 L flask (or greater), before autoclaving, due to boiling retardation
4. Autoclave

For plates

1. Mix dry ingredients and add dH₂O up to less than 1 Liter
2. After dissolved, add agar
3. Pour into 2 L flask (or greater)
4. Autoclave
5. Cool media down to handable temperatures (a laser thermometer is a great gadget to determine 'handable' temperatures)
6. Add appropriate antibiotic (usually somewhat between 1-10µl of a 50µM stock)
7. Pour the solution on plates under sterile conditions (constant flow) try to use all plates after opening of the packing
8. Let solidify about 30 min (cools faster when placed in singels on the bottom of the flow-bench add (description, date, additive, (owner))
9. store at 4°C