Hello,
Some time ago I asked the following question:
>Lightintensity is used to regulate the dilution-speed. The
>problem is that the algae are sticking to the glass, so the
>intensity measured is not any longer related to the
>concentration of algae.
>>Does anyone know how to prevent the algae from sticking to
>the glass-surface? The reactor is now running for two
>weeks, and the problem appeared when the liquid velocity
>was enlarged.
This were the answers I got.
You might try replacing the glass with plastic, which the flagella
would be less apt to adhere to.
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*You might try using a low concentration of a protein such as BSA or
*casein in your culture medium. I also seem to remember learning that
*folks who work with Tetrahymena use low concentrations of a surfactant
*in the culture medium. Marty Gorovsky at the University of Rochester
*might help you on the last point.
*
*We occassionally use BSA in our buffers for just the reason you
*mentioned, but we have never tried using it for culturing cells. I
*would expect that you would increase the potential for contamination
*and that you would get foaming. If I were you I would try to get in
*touch with someone who cultures large quantities of another
*protozoan.
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*I am familiar with the problem of Chlamy cells sticking to the gals
walls
*of fermentors, I grow them in continuou cultures for moths. I solve the
*problem in the followoing way. i introduce in the fermentor a teflon
*covered long magnetic rod which is sterilized at the same time as the
*fermentor and rests on the sides of the fermentorbottom. when there are
*cells sticking on the walls, i use an external stron magnet to catch the
*internal one and move the external magnet up and down or sideways so as
to
*scrap all the cells from the sinternal fermetno surface. this cleaning
*procedure is done once every one or two days for a few minutes. Hope
you
*may use this idea and eventually improve on it.
*Wish you luck,,
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*If I well remember, alternated day/night illumination leads
*to the production of synchronous culture.
*
*For your problem, why don't you try to use optical fibers
*as light source ?
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Of the previous answers I used only the magnetic rod, which works OK, but
is
not possible to clean the whole reactor with it, because there is a
double
wall to cool the suspension.
A few days ago I added about 2% vol of polystyrene beads and they seam to
be
able to keep the walls fairly well cleaned.
Thanks for all the responds,
Greetings,
--
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. (Tjibbe_) Chris) ( ) (_) .
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. Tjibbe-Chris.Kuipers at STUDENT.PK.WAU.NL .
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. 'De wereld gaat aan vlijt ten onder .
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. 'The world goes down from diligence' .
. Max Dendermonde .
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