초록
<P><B>Abstract</B></P> <P>This study investigated the determination of hydrogen production by three H<SUB>2</SUB>-producing microorganisms (<I>Thermotoga maritima, Thermococcus kodakarensis</I> KOD1 and <I>Enterobacter cloacae)</I> cultured in 116-mL serum bottles. A gas pressure manometer was used to measure total pressure in the serum-bottle headspace. It was demonstrated that total pressure is the sum of the saturation pressure of water, the pressure expansion of gases, and the partial pressures of H<SUB>2</SUB> ( <SUB> P <SUB> gH 2 </SUB> </SUB> ) and CO<SUB>2</SUB> ( <SUB> P <SUB> gCO 2 </SUB> </SUB> ). A linear relationship was established between the partial pressure of H<SUB>2</SUB> measured by gas chromatography and the sum of the partial pressures of H<SUB>2</SUB> and CO<SUB>2</SUB> measured by the manometer. When pH of culture medium was not controlled (pH decreased from 7 to 5), the <SUB> P <SUB> gH 2 </SUB> </SUB> / <SUB> P <SUB> gCO 2 </SUB> </SUB> ratio was close to stoichiometric H<SUB>2</SUB>/CO<SUB>2</SUB> yield ratio of the most plausible metabolic pathways of each strain. <SUB> P <SUB> gH 2 </SUB> </SUB> / <SUB> P <SUB> gCO 2 </SUB> </SUB> values were 1.7, 1.9 and 0.9 for <I>T. maritima</I>, <I>T. kodakarensis</I> and <I>E. cloacae</I>, respectively. In these experimental conditions, <SUB> P <SUB> gH 2 </SUB> </SUB> can be deduced from total pressure measured by manometer.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The H<SUB>2</SUB> producing capacities of <I>T. maritima</I>, <I>T. kodakarensis and E. cloacae</I> were studied in 116mL-serum-bottle. </LI> <LI> A linear relationship was shown between the H<SUB>2</SUB> partial pressure and the sum of these of H<SUB>2</SUB> and CO<SUB>2</SUB> of each microorganisms. </LI> <LI> Under some assumptions, determination of H<SUB>2</SUB> partial pressure was achievable using a simple manometer. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>