Doomsday wrote:TCMaster wrote:Have been prepared liquid media (MS, QL, DKW) and keep them in fridge for years. As long as they are clear then it's OK. They are good fertilizer so you can use and test them in vitro and vivo.
Awesome. Thanks for the answer. I'll double check to make sure nothing has grown in it, and if not, I'll give it a try with a few jars.
I never use refrigerated liquid media more than six weeks old, since there are many issues with potential contamination. On more than a few occasions, we've plated samples of stored media and have discovered bacterial, fungal, or algal spores -- many of which are resistant even to autoclaving.
At the very least, adjust the pH once again and autoclave for the maximum time, at the highest setting . . .