An Iron Corrosion-Assisted H2-Supplying System: A Novel Culture Method for Methanogens and Acetogens under Low H2 Conditions

Here we report development of a novel culture method that can easily and continuously supply low concentration of H2 for methanogens and acetogens. We focused on the reaction of iron corrosion, since metallic iron spontaneously and slowly generate H2 in anoxic solution. We constructed a culture system, namely iron corrosion-assisted H2-supplying (iCH) system, by connecting gas phases of two vials (one for iron corrosion reaction and the other for culturing microorganisms) by a stainless-steel pipe. The results obtained in this study demonstrated that the iCH system facilitates culture of anaerobic microorganisms under low H2 conditions, which would enable to selectively culture microorganisms specialized for low H2 environments.