I am looking for a gelling agent that can be used in place of agar, where its carbon must not be bioavailable for fungi. I have read about pluronic polyol f127 as substitute for agar. Can fungi metabolize carbon from this polymer?
It is known that some species of fungi can use hydrocarbons as their carbon source. Polyethers like pluronic are less chemically inert than hydrocarbons. Indeed, degradation of polyethylene glycols by microorganisms is a well studied process (see DOI: 10.1007/s00253-001-0850-2 for example). Gloeophyllum trabeum is known to degrade poly(ethylene oxide) by a non-enzymatic, oxidative process (Proc. Natl. Acad. Sci. USA. 1998, 95(18):10373-7). Given those facts, there is a very good chance that some species of fungi can metabolize pluronics and similar compounds.