David asked ...
 
> Has anybody impregnated sterile filter-paper disks with some dissovled
> propolis?  If so, do you know the best solvent?
>
> David Kesler      Rhodes College      [log in to unmask]
 
Malcolm answer :
 
> Alcohol (ethanol).
>
> --
> Malcolm Roe                            Phone  :  +44 442 230000 ext 4104
 
To be complete, the answer must be a little more subtle ...
 
1/ Ethanol
 
  Different described methods use either absolute alcohol (96 % ethanol?)
or 70 % ethanol.  It seems that the latest (70%) is better to extract *all*
the antibiotic substances.  After this first choice you could work cold,
warm or hot ...  perhaps some antibacterial are hot-sensitive.
 
2/ Ether (diethyl ether)
 
  Ether is a good solvent for propolis when people must evaporate the
solvent.  I don't know if the full antibacterial substances are extracted
but all the small organic compounds are in the extract with rapidly drying.
 
3/ DMSO (dimethyl sulfoxide or methyl sulfoxide)
 
  DMSO is an excellent solvent for propolis when you must add them to
solutions for cultured cells when ethanol may interfere in the milieu (or to
be toxic to the cells).
 
There are a lot of papers about propolis and its extract(ion) ... I don't
have the references within reach but I can find it if necessary !
 
Jean-Marie                      email : [log in to unmask]
 
 
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   Baudouin Albert Charles Leopold Axel Maria Gustave of Saxe-Coburg Gotha
                               (1930-1993)
              Fifth Constitutional King of The Belgians, 1950-1993
 
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