초록
<P><B>Abstract</B></P> <P>This study demonstrates the potential for biohydrogen production in a co-culture of two ecologically distant species, <I>Thermatoga neapolitana</I> and <I>Caldicellulosiruptor saccharolyticus</I>, and the development of a quantitative real-time PCR (qPCR) method for quantifying the hyperthermophilic bacterium of the genus <I>Thermotoga.</I> Substrate utilization and H<SUB>2</SUB> production performance was compared to those of their individual cultures. The highest H<SUB>2</SUB> yields obtained were 2.7 ± 0.05, 2.5 ± 0.07 and 2.8 ± 0.09 mol H<SUB>2</SUB>/mol glucose for <I>C. saccharolyticus</I>, <I>T. neapolitana,</I> and their co-culture respectively. Statistical analysis comparing the H<SUB>2</SUB> production rate of the co-culture to either <I>C. saccahrolyticus</I> or <I>T. neapolitana</I> pure cultures indicated a significant difference in the H<SUB>2</SUB> production rate (p < 0.05: <I>t</I>-test), with the highest rate of H<SUB>2</SUB> production (36.02 mL L<SUP>−1</SUP> h<SUP>−1</SUP>) observed from the co-culture fermentations. In order to monitor the presence of <I>T. neapolitana</I> in the bioprocess, we developed a qPCR method using 16S rRNA gene and hydrogenase (hydA) gene targets. The qPCR data using <I>hydA</I> primers specific to <I>T. neapolitana</I> showed an increase in <I>hydA</I> gene copies from 3.32 × 10<SUP>7</SUP> to 4.4 × 10<SUP>8</SUP> <I>hydA</I> gene copies per mL confirming the influence of <I>T. neapolitana</I> in the synthetic consortium.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Co-culture of <I>T. neapolitana</I> and <I>C. saccharolyticus</I> led to fast substrate depletion. </LI> <LI> Maximum H<SUB>2</SUB> yield of 2.8 (±0.09) mol H<SUB>2</SUB>/mol glucose was obtained from co-culture. </LI> <LI> Developed qPCR methods for genus and species specific monitoring of <I>Thermotoga</I> sp. </LI> <LI> Increased hydA gene copies confirm the influence of <I>T. neapolitana</I> in the co-culture. </LI> <LI> Demonstrates synergistic potential of ecologically distant microbes in H<SUB>2</SUB> production. </LI> </UL> </P>