Culture can be stored for (1) one year and the recovery rate declines with time. After three years, it's better to grow them on the fresh broth and check the recovery rate. Be careful of rapid thawing of culture and should be culture the bacteria in fresh broth to increase OD 0.4-0.6.

Hello

Usually bacterial glycerol stock is stored at - 80 degree C for long-term storage (many years). In this case, the probability of bacteria reviving is less because the glycerol stock has been stored at - 20 degree C for 3 years.

Nevertheless, you can revive bacteria from the glycerol stock by placing the frozen tube on ice, and with the help of sterile loop, pipette tip or toothpick scrape some of the frozen bacteria from the top and streak the bacteria onto LB agar plate. Grow the bacteria overnight at the appropriate temperature. You can then isolate single colony and inoculate in broth medium. This is done to remove any contaminants that could be present in the glycerol stock.

Care must be taken to see that the glycerol stock does not thaw.

I hope this helps.

Best,

It can be saved for more than half a year.

Inoculate the bacteria in glycerol into beef extract peptone liquid medium, 37 ℃, 150 rpm, and culture for 24 hours to activate the bacteria

Nur Amira Rosli