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Glycerol stock - must we use fresh culture? - (Jul/09/2009 )

It seems to be a silly question. but how much does it affect when one used old culture (1-2 days old, kept at 4deg) vs fresh overnight culture when doing glycerol stock? i'm aware that using fresh culture is strongly recommended, but it's not time and cost effective sometimes. anyone has any experience using not-so-fresh culture when making glycerol stock?

my samples are transformed DH5a and i have lots of them (carrying different plasmids).

-wia84-

I would not make stock from old culture.
sometime I had some difficulties to restart culture I kept in the fridge.
Stock is important, it's something you must trust it will start again.

-little mouse-

alright. just need some advice if anyone ever do glycerol stock with old culture.
our plasmids (abt 50 of them) are running low and i just did transformation and miniprep to confirm. and i have some 'left over' from culture for miniprep. that's y the idea of using the 'old' culture.

anyway, thanks for sharing!

-wia84-

wia84 on Jul 9 2009, 08:21 AM said:

alright. just need some advice if anyone ever do glycerol stock with old culture.
our plasmids (abt 50 of them) are running low and i just did transformation and miniprep to confirm. and i have some 'left over' from culture for miniprep. that's y the idea of using the 'old' culture.

anyway, thanks for sharing!

I have used glycerol stocks dating about 10 year back. It works. I think the most important reason they may go bad is due to freezer malfunction at some point in its history.

-cellcounter-

cellcounter on Jul 9 2009, 06:58 PM said:

wia84 on Jul 9 2009, 08:21 AM said:

alright. just need some advice if anyone ever do glycerol stock with old culture.
our plasmids (abt 50 of them) are running low and i just did transformation and miniprep to confirm. and i have some 'left over' from culture for miniprep. that's y the idea of using the 'old' culture.

anyway, thanks for sharing!

I have used glycerol stocks dating about 10 year back. It works. I think the most important reason they may go bad is due to freezer malfunction at some point in its history.


the question was not about the old glycerol stocks, but about cultures kept in the fridge that could be used to do glycerol stock.

-little mouse-

little mouse on Jul 10 2009, 01:15 AM said:

cellcounter on Jul 9 2009, 06:58 PM said:

wia84 on Jul 9 2009, 08:21 AM said:

alright. just need some advice if anyone ever do glycerol stock with old culture.
our plasmids (abt 50 of them) are running low and i just did transformation and miniprep to confirm. and i have some 'left over' from culture for miniprep. that's y the idea of using the 'old' culture.

anyway, thanks for sharing!

I have used glycerol stocks dating about 10 year back. It works. I think the most important reason they may go bad is due to freezer malfunction at some point in its history.


the question was not about the old glycerol stocks, but about cultures kept in the fridge that could be used to do glycerol stock.

Ouch!

-cellcounter-

wia84 on Jul 9 2009, 11:21 PM said:

alright. just need some advice if anyone ever do glycerol stock with old culture.
our plasmids (abt 50 of them) are running low and i just did transformation and miniprep to confirm. and i have some 'left over' from culture for miniprep. that's y the idea of using the 'old' culture.

anyway, thanks for sharing!


I get wad you mean by this. I once had 5mL of culture and I took 1 mL out for my glycerol stock, and the rest of the 4mL for my miniprep. It works. It is still new anyway.

-jiajia1987-