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Solvent for Agar - is there a solvent for dissolving agar (Feb/11/2009 )

Dear all,

i wish to quantify the biomass growing on an agar plate. to do this i want to liquify the agar either with heat or with a suitable solvent and pull it through a filter, leaving the biomass on the filter membrane, which i can then weigh.

obviously i dont want to damage my cells such that they fall through the filter.

has anyone had any experience with doing this? whats a good solvent for dissolving agar with little heat?

any help will be appreciated




Usually you are using some sort of filter material (I think its nitrocellulose-membrane) for this purpose. A quick literature research will help you to identify the right material for your fungus.

The fungus grows on the membrane but still gets all nutrients from the medium. Then you take the fungal biomass with the filter/membrane off your plate, dry it and determine the biomass. You should not forget to write down the weight of your membrane before putting it on the agar plate, it has to be subtracted from your biomass :blink:


Good response, gebirgz. Fungal biomass would certainly be compromised by an agar "solvent" (and I'm not aware of any for this purpose).


NEB sells the enzyme beta-agarase, which will degrade agar to liquid form.
I don't know what it might do to your cells.


Eikinella also degrades agar. These are not gong to break it down for the purpose offered here.


The enzyme will be the best choice, but it can be too expensive.

If you only want to know the amount of biomass generated, you have to scrap/ rinse to get most of them off the plate and spin it to collect biomass that way.


genehunter. Have you data that demonstrate sufficient digestion of an agar plate full of medium and that the prep will not affect recovery of other biomass. Consider the presence of other enzymatic capabilities in the enzyme prep, the range of polysaccharides that may be hydrolyzed esp. with the likely necessity of multiple activities to bring agar to a soluble endpoint.

Failing that - the application of enzyme is not justified. In any case, geberg's sugg is much better.