Á cs, Norbert; Bagi, Zoltá n; Rá khely, Gá bor; Miná rovics, Já nos; Nagy, Katalin; Ková cs, Korné l L.
초록
<P><B>Abstract</B></P> <P>The rate-limiting nature of the hydrogen concentration prevailing in the anaerobic digester has been recognized, but the associated alterations in the microbial community are unknown. In response to the addition of <I>Enterobacter cloacae</I> cells in laboratory anaerobic digesters, the level of biogas production was augmented. Terminal restriction fragment length polymorphism (T-RFLP) and real-time polymerase chain reaction (Real-Time PCR) were used to study the survival of mesophilic hydrogen-producing bacteria and the effects of their presence on the composition of the other members of the bacterial community. <I>E. cloacae</I> proved to maintain a stable cell number and to influence the microbial composition of the system. Bioaugmentation by a single strain added to the natural biogas-producing microbial community was demonstrated. The community underwent pronounced changes as a result of the relatively slight initial shift in the microbiological system, responding sensitively to the alterations in local hydrogen concentration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Addition of H<SUB>2</SUB> producing <I>Enterobacter cloacae</I> augmented biogas production. </LI> <LI> <I>E. cloacae</I> became a stable member of the biogas producing microbial community. </LI> <LI> Addition of <I>E. cloacae</I> significantly altered the community composition. </LI> <LI> Polymer degrading <I>Clostridiales</I> increased their abundance dramatically. </LI> <LI> A syntrophic relationship between polymer degradation and in situ H<SUB>2</SUB> generation is suggested. </LI> </UL> </P>