Re: Fungi Isolation

in article [EMAIL PROTECTED], Scott Coutts at
[EMAIL PROTECTED] wrote on 11/12/03 5:19 PM:

> 
> 
> Colin Davidson wrote:
>> "Monica Enamorado" <[EMAIL PROTECTED]> wrote in message
>> news:[EMAIL PROTECTED]
>> 
>>> I'm working on fungi isolation for bioactive metabolites search,
>>> nowadays I'm on the isolation stage.
>>> 
>>> I have four samples of different fungi, these samples are polluted
>>> with bacteria although the cultivation has a concentration of
>>> cephotaxime of 5 micrograms/ml.
>>> 
>>> I have checked for many possible sources of pollution, I have improved
>>> the manipulation procedures but the pollution still persists.
>>> 
>>> I would like to know about sterile procedures or antibiotics to
>>> eliminate the bacteria from these samples. I would appreciate any
>>> suggestions and references (papers, books, web sites) on this topic.
>> 
>> 
>> 
>> Hmm. You're already using a fairly broad spectrum antibiotic, but you seem
>> not to be getting rig of your contaminant that way. I'd try either upping
>> the concentration of antibiotic or using a different antibiotic; you might
>> just have something that isn't particularly susceptible to this antibiotic.
>> I might be tempted to streak out the bacterium, Gram stain it and pick an
>> appropriate antibiotic based on that.
>> 
> 
> Yeah, I agree. I'd streak out, stain a bacterial colony, and try some
> susceptibility tests on it.
> 
> Monica: Do you have access to an antibiotic disc dispenser? That will
> make it easier.
> 
> Scott.
> 

I've seen success with that kind of thinking. Our Mycology guy used to
streak out a blood Mueller Hinton plate with the contaminated specimen and
drop antibiotic disks - depending on the Gram stain. He usually was able to
pick off a pure fungal colony in the zone around one of the disks.

Another idea is to be very careful and tease a tiny piece of the aerial
hyphae and plant that to your selective media.
-- 
John Gentile                            Secretary,  Rhode Island Apple Group
[EMAIL PROTECTED]                      RIAG Web page:  www.wbwip.com/riag/
"I never make mistakes, I only have unexpected learning opportunities!"