Tryptone soya broth (TSB) for cryo-storage of yeasts and moulds

A general recipe for storing yeasts and moulds at -80°C.
The TSB is aliquoted in sterile 2 ml tubes with screw caps (e.g. Sarstedt 72.694.005) or other tubes withstanding freezing and thawing.

Cryo protectant for storing cultures at -80°C
Total volume in ml                           1000 ml
Weigh Tryptone soya broth (Oxoid, CM0129) 30.00 g
Measure Distilled water or demineralized water 875.00 ml
  Glycerin anhydrous (Sigma-Aldrich 49779) 1 125.00 ml
Soak mix and soak for 15 min.  
Sterilization                15 min. at 121°C  
  cool to 50°C  
Storage 3 months at 2-8°C  
Aliquot aliquot the broth in 2 ml sterile tube with screw cap
(Sarstedt 72.694.005)
1 ml
pH N/A  

1 if anhydrous glycerin is not available, use 99% or 87% glycerin. Adjust volumes of water and glycerin accordingly to reach
12.5% glycerin end concentration.

e.g. with 87% glycerin add ~142 ml instead of 125 ml and lowering the amount of water.


Yeasts: collect yeast cells with a 10 µl inoculation loop and make suspension in TSB, label tube and store.
Moulds: sporulating cultures can be swabbed with a wet, sterile cotton swab. Dry sporulating species, like Penicillium/Aspergillus,
should be swabbed with a wet cotton swab containing 5% Tween 20. If strains are not sporulating, small pieces (8-10 pieces) 2x2 mm can be cut from the agar and placed in TSB.