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Trying To Culture Oil Eating Microbes? - (Dec/17/2010 )

Hello out there.....

I'm not a Microbiologist so this is probably why the process below is
not working....:(
Any help or comments would be appreciated.

I am trying to culture oil eating microbes and measure their growth by
looking at the co2 levels they are emitting.

I know the normal thing would be to culture them in an agar dish and
score visually but I got the bright idea that measuring co2 emissions
would provide an earler and more sensitive indication of their growth.

Here is how I'm doing it:

Have a quart Ball fruit jar filled with distilled water about 2" below
PH about 6.0-temp is about 70 degrees.
Purchased some Oil Eating Microbes from a science lab, added 1/2
teaspoon to the jar.
Added Butanol as the Hydrocarbon food. Added enough to create about a
1/4" oil slick on top of the jar.

Placed lid on jar.

Jar lid has an air tight inlet and outlet tube that connects to my co2
meter. Co2 meter will measure down to 50ppm.Co2 meter has an injector
pump and I am pulling air from the headspace of the jar, through the
co2 meter, back into the jar.

The incubation has been running 72 hours and I'm not seeing any real
elevation in co2 and no real visible indication of growth.Room c02 is
about 400ppm and the jar co2 is about 1600 ppm however it read that
almost immediately after I started the incubation and that reading has
actually dropped some and is not increasing.

I am using Butanol instead of a light grade oil for food. Light grade
oil is usually supplied with the microbes I bought but I am looking
for bugs that eat Butanol type (light) Hydrocarbons.

The jar is sealed where the normal science kit indicated leaving the
jar open , however I needed it to be sealed in order to trap the c02.
Also I figured there was enough O2 in the headspace of the jar for
some growth.
I have also considered the cO2 could actually choke the bugs but I
don't think co2 levels have ever got to that point yet.

Many have said add sugar or other nutrients to kick start growth but I
don't want to get a Heinz 57 colony growing. I only want to stimulate
Hydrocarbon specific bacteria.

Anybody have any thoughts, ideas, or suggestions?

If someone can help me with this I'll gladly pay a couple hundred
bucks for your time.



It could be that your bacteria require O2 to break down the oil (we'll come to butanol in a moment) - in which case having a slick of butanol on top of the cultures is probably starving them of oxygen. You could try incorporating the butanol into the medium somehow, perhaps through the use of emulsifiers.

The bugs may not metabolise the butanol properly, if at all, you may have to train them to do so by supplying different increasing concentrations of butanol in the oil over time.