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.
| 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 |
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.
