Two-phase medium – a new approach to microbiological culturing

We tested a new two-phase culture medium for culturing microorganisms, in particular algae and fungi. In media composed of mixed gel and solid phases of granite, basalt, sandstone, limestone and sodium glass, we observed the growth of selected species inhabiting the boundaries of the gel medium with the solid phase. The species used were Klebsormidium dissectum (F.Gay) H.Ettl & Gärtner, Vischeria polyphem (Pitschmann) Kryvenda, Rybalka, Wolf & Friedl and Muriella decolor Vischer (algae); and Aspergillus tubingensis R.Mosseray, Aureobasidium pullulans (de Bary) G.Arnaud, Chaetomium globosum Kunze and Penicillium sp. Link (fungi). In the six-weeks period of parallel cultures, the growth rate of the algae inoculum in two-phase media was twice that observed in the control culture (gel medium). The algae also maintained high viability in the new medium.