Direct interspecies electron transfer via conductive materials: A perspective for anaerobic digestion applications

Upgrading continuous H2gas recovery from rice straw hydrolysate via fermentation process amended with magnetite nanoparticles

“…This condition diminished the thermodynamically unfavorable H 2 ‐producing reactions. However, NP‐loaded reactors have the ability to handle this problem compared with conventional types, whereas NPs acted as e − shuttles between syntrophic bacteria . However, when OLR exceeding 1.6 g COD /L/day suppressed HPB and led to diminishing the ability of MNPs to stimulate higher hyd activity as shown in Figure B, in turn, a significant drop at HPR was acquired (Figure A).…”

“…However, the selection of magnetite NPs (Fe 3 O 4 ) to be investigated in this study was based on its potential for enhancing the rate‐limiting hydrolysis process via dissimilatory metal reduction reaction . In addition, magnetite has higher conductivity than hematite (10 6 times) . Whereas, metal NPs can play the role of electron shuttles to facilitate the electron transfer between enzymes, ie, ferredoxin oxidoreductase and hydrogenases secreted from syntrophic bacteria which enhances the anaerobic glucose degradation process and promotes the protons' reduction to H 2.…”

Application of 2‐hydroxy‐1,4‐naphthoquinone‐ graphene oxide (HNQ‐GO) composite as recyclable catalyst to enhance Cr(VI) reduction by Shewanella xiamenensis

“…Nonetheless, the biological reduction rate might be strongly influenced or directly dependent on the standard redox potential of QCs . Several insoluble electron shuttles have been extensively applied to stimulate EET, including graphene sheets, biochar and carbon nanotubes . Because of the heterogeneities derived from microbial genetic diversity and structural and functional characteristics of electron shuttles, the internal relationships between Shewanella and different electron shuttles might elicit differential environmental effects.…”

“…Considering the good catalytic activity and stability of QCs in solid engineered materials, a QC‐based engineered material prepared by immobilizing QCs in graphene oxide (GO) may facilitate high electron conductivity, a large specific surface area for enhancing reactions, and high durability against corrosion. To date, a number of studies have focused on identifying soluble QCs or insoluble carbon based conductive materials that can stimulate direct interspecies electron transfer (DIET) . Likewise, the mechanisms regarding enhanced EET performance in the presence of a specific electron shuttle have been explored .…”

“…17 Several insoluble electron shuttles have been extensively applied to stimulate EET, including graphene sheets, biochar and carbon nanotubes. 18 Because of the heterogeneities derived from microbial genetic diversity and structural and functional characteristics of electron shuttles, the internal relationships between Shewanella and different electron shuttles might elicit differential environmental effects. Thus, careful selection of the most effective electron shuttle for Shewanella-mediated biosystems should be rigorously established.…”