Glycerol

Glycerol or glycerin

We mainly use glycerol as a "cryoprotectant" to store E. coli, fungal mycelia or yeast cells in suspended animation at -80°C. The glycerol in the medium/water disrupts the crystal lattice formation of ice crystals, thereby reducing damage by ice crystals.

Sterilize Glycerol by filtration (preferred) or autoclaving (what we actually do, because easier, but this produces some acrolein which is mutagenic and auto fluorescent).
Make a dilution for 2X the appropriate concentration.
We use:

• 50% for E. coli --> final concentration 25%
• 30% for yeast and mycelia --> final concentration 15%