Sugars in yeast ext.?

[Chuck Staben]

We had a problem with a single batch (of course I did not record the number) of yeast extract 
that could have resulted from sugar contamination.  We study a drug (pentamidine) that 
inhibits growth of yeast only under certain conditions, those usually associated with need for 
functional mitochondria (glycerol, eg.).  One batch of YE suppressed susceptibility, which 
could mean that it contained a sugar that remediated the inhibition (like glucose--but I would 
have expected that the concentration would have had to be at least 0.05% in the medium.)
We switched yeast extract and had no further problems.