3.04. Preparing Growth

  1. Measure 15 g of LB powder per liter of solution desired.
  2. To a beaker or Erlenmeyer flask, add the LB powder, stir bar, and desired volume of dH2O.
  3. Stir the mixture until all of the LB powder has dissolved.
  4. Transfer the mixture to an autoclave-safe container or cover the lid with the container with aluminum foil.
  5. Place a small piece of autoclave tape on the lid of the container.
  6. Before placing the mixture in the autoclave, make sure that the lid is not airtight.
  7. Autoclave the mixture on the liquid setting for 20 minutes.
  8. Store the solution at room temperature.

LB agar is a solid growth medium for bacteria that can be melted and poured onto plates. The following is a procedure for how to prepare LB agar.

  1. Measure 15 g of LB powder and 15 g of agar per liter.
  2. Dissolve LB powder in dH2O.
  3. Transfer LB solution to autoclave-safe container.
  4. Add agar to solution.
  5. Stir the mixture by swirling the autoclave bottles.
  6. Autoclave the mixture on the liquid setting for 20 minutes.
  7. Store the mixture in the refrigerator.