You can use Agar-Tubes

fill one tube to 2/3 with steril LB add 0,6 % Agar and add max. 10 mg Cystein

pick one of your colony

and put it a few times in the agar

growth overnight at 37 °C

storage in darkness at 4 °C

renew it twice a year

Inoculate 4.5 ml of nutrient broth with bacteria. After incubation at 37 ° C overnight to obtain an optimum amount of bacteria, add 0.5 ml of DMSO and mix vigorously. Then place 1 ml aliquots den cryotubes The final concentration of the cryopreservative, glycerol or DMSO, should be at least 10%, v/v.

Una manera clásica de almacenar cualquier tipo de bacteria es suspenderla en leche desnatada adicionada de 5-10% de Glicerina (para que no se formen cristales durante la descongelación), hacer alícuotas y congelar. Para recuperarla, descongelar a 4ºC, resuspender por homogeinización y resembrar en los medios adecuados.

why dont to hand it over to culture collection centres like DSMZ for archiving at a low cost. for 1yr plus it would be good to freeze dry the sample in ampoules.

The best quality long-term maintenance of microbial cultures is certainly cryostorage in liquid nitrogen (culture medium containing 10% DMSO or 10% glycerol), if you have this possibility. Storage of yeast cultures at -20 C may be detrimental to them, better is routine passaging.