How to make nutrient agar

[rae]

Peptone is the nutrient that feeds the bacteria etc. Pepsin is an enzyme I don't think it is the same it will possibly digest your agar.

My recipe says : ....or 3g/L of nutrient. eg. beef cube,Oxo, Bonox, Vegemite or marmite. Hope this helps.

[judyjolly]

Hi All
I have a new jar of Peptone. Thought I'd try weighing into 5gm lots and freezing but found that to be a bit messy and needing lots of patience, which I don't have at present. Keeping in the fridge sounds a good idea too. Has anyone tried storing it in a dessicator with self indicating silica gel, to keep dry? Perhaps I'll try that.
Thanks for ideas
Judy

[dss8386]

10g Agar
2.5g Bonox
1.5 Peptone
500ml Hot water

Makes about 30 plates.

I also make plates with the bacteria in the gel, allow the agar to cool to 50C then add bacteria (rhodospirillum works a treat) give it a mix. Alot better then onnoculating.

[rae]

The last time I bought a container of peptone I jammed a silica gel pouch into the lid. I have no problems since.

[Ian]

The recipe that I have used for the last 6 years (from Manual for Science Assistants, (dated 4 BC!)) Calls for 5g Peptone, 5g NaCl, 2g Vegemite, 1g Bonox and 15 g Agar for 1 Litre of mixture. It always works well. This time I made it with everything EXCEPT the peptone, and we barely got any cultures grow at all!. Everything was exactly the same except the Peptone. Next time I might try 5 g of Gelatine.

That is a good idea about the silica jel pouch, Rae.

Cheers
Ian