Hi Vikki, 

Vegetable oil is widely used as an alternative to substitute silicon based anti-foams. If the fungi you are working with will not use it as carbon source you can use it safely. I have used vegetable oil in my bacterial cultures without any problem and I know a few colleagues who have used in fungal fermentation as well.  

Hope this is useful.

Hi Vikki,

I agree with Artun to use of vegetable oils as anti-foam agent. Fungal fermentation I had used as substrate oilseed cake power which given economical process was well as very low foam production during fermentation process.

For microbial fermentation I found anti-foam 204  from sigma given batter result in low concentration .

Hope this may useful 

You can use mineral oil. But check the compatibility before using it. Most of the microbes don't metabolize mineral oil. 

Also check the following links for organic oil based and other defoamers. 

http://www.airproducts.com/products/Chemicals/Defoamers-Deaerators/Organic-Oil-Defoamers.aspx

https://www.aerosil.com/product/aerosil/Documents/TI-1391-Improving-Sedimentation-Stability-of-SIPERNAT-D-10-in-Mineral-Oil-based-Defoamer-Formulations-EN.pdf

http://www.harmonyadditive.com/100active-mineral-oil-based-defoamer.html

Hey Vikki

I should say that my colleague use vegetable oils instead of commercial anti-foam in the fermentation of Streptomycetes for biomass production. I should say that the amount which is used is low so the won't have any problem regarding the consumption of it in the fermentor.

Hi Vikki

You different kinds of Anti-Foam activity, depending on Oil / water effects, others like Pluronics have detergent effects creating a defined foam that is easier to handle.

So basically you have different possibilities to break foams; he effect is also less based on the absolute concentration of your antifoam in reaction, so it is mostly not enough just to add the amount of anti-foam before the start of the reaction. In technical apllicationsyou creat fine sprays in the gas-rooms of fermentors f.E. where you keep the foam down locally with a very low amount of spray.

This border-surface-effects are also used in the down-stream processing, in phase-separations f.E.

You have a chance to avoid foams with your gas-inlet, f.E, you have circulating systems with a smal impeller stirrer and a double-wall  for fermentors that prevent the forming of too much foams.

The forming of foams and the solubility of your gases can also be influenced by the backpressure in your system.... an overpressure of 1bar is very efficient for more effective oxygene usage and lowers the flow of gas that you have to let inside....and in the same time the possibilty of foaming

Plant oils can be used, if you are limited with the price or if silicone-based reagents have to much toxic side-effects

For oil-formed anti-foams, you have to keep in mind, that cleaning of flasks or fermentors can get extremly difficult and you might have effects on later reactions which you carry out in this devices, because the oil films are not removed propperly.

What would be the typical concentration of vegetable oil used as an anti-foaming agent for use in bacterial culture?

I am growing E.coli cells in sodium oleate with brij-58 as a surfactant to make it soluble in water. How to solve foaming problem? Edit

INSTRUMENT :  Sartorius Biostat Aplus Fermenter

As soon as I add the SODIUM OLEATE + BRIZ-58 into the M9 media, it starts bubbling. Which antifoam has to be used in this case where sodium oleate is the only carbon source with briz as a surfactant

 Hi Artun,

You mentioned that you have used vegetable oil in your bacterial culture to quench foaming. I am planning to use Eppendorf BioFlo 115 fermentor for probiotics culture. Do you know if the vegetable oil is suitable?

Best,

Changge