Glycerol in Freezing media -Reply

[Glen Ulett]

Ted Snazelle wrote:
> 
> Years ago I would mix antisera 1:1 with glycerol and then store in the
> freezer until needed.  Supposedly the glycerol prevented ice crystal
> formation which would have disrupted the structure of the
> immunoglobulins.  The 1:1 mixture of antiserum and glycerol does not
> freeze in the freezer.  As to what really happens with cells, I can only
> presume the same might be true, i.e. minimizing ice crystal formation.  I
> routinely store bacterial cultures in a glycerol -broth mixture over sterile
> glass beads in the freezer.  The mixture does freeze; however, I readily
> activate bacterial cultures stored this way for at least two years in my
> laboratory.
> 
> Ted Snazelle
> Mississippi College
> 
> >>> Louis Geller <bbbbd at sprynet.com> 09/25/96 01:48am >>>
> Hi.
>         I was wondering exactly it is necessary to have glycerol in
> freezing medium for bacteria, yeast, and animal cells.
>         Exactly how does the glycerol protect the cells?
>         Thanks in advance,
>         Louis Geller...
>         lgeller at csulb.edu
>         bbbbd at sprynet.comHi Louis,
	I've have collegues here who also freeze their bacterial cultures 
 with 15% glycerol, however I'm not so sure whether it really is 
necessary. I have frozen many cultures down without it, and I readily get 
back 10>8 organisms per ml from 16 hr broth cultures. I'm not sure how it 
acts to prevent crystal formation in cells though.
-- 
Best Regards,

Glen Ulett.
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