Dynamics of different bacterial communities are capable of generating sustainable electricity from microbial fuel cells with organic waste.
The relationship between the bacterial communities in anolyte and anode biofilms and the electrochemical properties of microbial fuel cells (MFCs) was investigated when a complex organic waste-decomposing solution was continuously supplied to MFCs as an electron donor. The current density increased gradually and was maintained at approximately 100 to 150 mA m(-2). Polarization curve analyses revealed that the maximum power density was 7.4 W m(-3) with an internal resistance of 110 Ω. Bacterial community structures in the organic waste-decomposing solution and MFCs differed from each other. Clonal analyses targeting 16S rRNA genes indicated that bacterial communities in the biofilms on MFCs developed to specific communities dominated by novel Geobacter. Multidimensional scaling analyses based on DGGE profiles revealed that bacterial communities in the organic waste-decomposing solution fluctuated and had no dynamic equilibrium. Bacterial communities on the anolyte in MFCs had a dynamic equilibrium with fluctuations, while those of the biofilm converged to the Geobacter-dominated structure. These bacterial community dynamics of MFCs differed from those of control-MFCs under open circuit conditions. These results suggested that bacterial communities in the anolyte and biofilm have a gentle symbiotic system through electron flow, which resulted in the advance of current density from complex organic waste.
Department of Applied Chemistry and Biological Engineering, Graduate School of Engineering, Shizuoka University.
Shuji
S
Yamamoto
Kei
K
Suzuki
Yoko
Y
Araki
Hiroki
H
Mochihara
Tetsuya
T
Hosokawa
Hiroko
H
Kubota
Yusuke
Y
Chiba
Owen
O
Rubaba
Yosuke
Y
Tashiro
Hiroyuki
H
Futamata
D001483:Base Sequence; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018441:Biofilms / Q000254:growth & development*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004560:Electricity; D004563:Electrochemistry; D004566:Electrodes / Q000382:microbiology; D045302:Geobacter / Q000145:classification / Q000235:genetics / Q000502:physiology*; D017744:Medical Waste Disposal; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial; D017744:Medical Waste Disposal; D012336:RNA, Ribosomal, 16S