Autoclave Clarifications for Basic Yeast Growth Protocol

Using the Pioreactor
1

I have a few questions about step 2 in the guide for growing yeast in YPD medium.

  1. Do I add the prepared YPD medium to the vial with stirrer bar/cap and then autoclave this all together? Or do I autoclave the vial first then add the prepared YPD broth? I am not sure what is meant and am unsure if the heat of the autoclave would denature the YPD medium. I do understand that I only add the yeast after autoclaving (logically).
  2. Do I leave the cap loose when autoclaving?
  3. I take the tubes out when autoclaving, right? How should I clean the tubes?
2

Hi @joe_pio,

These are good questions:

  1. You’ll need some way to autoclave the prepared YPD media. We have always autoclaved the YPD in the vial. The nice thing about our small vial volumes is that it only needs to be a max temp for a few minutes to be sterile. This reduces any YPD denaturing or burning.
  2. Yes, I suggest leaving the cap a bit loose.
  3. No, you can leave them in the cap to be autoclaved too.