Arsenic alleviation in rice by using paddy soil microbial fuel cells
- 19 Downloads
Background and aims
Rice (Oryza sativa L.) consumption is a major route of dietary exposure to arsenic (As) in humans. One main reason for the high accumulation of As in rice grain is the high bioavailability of As in porewater of flooded paddy soil. Recently, it has been shown that the application of soil microbial fuel cell (sMFC) can significantly reduce soil porewater As concentration, however, the effect of sMFC on As accumulation in rice is unknown. Hence, this study was aimed at reducing the As uptake in rice grown in As contaminated soil by sMFCs.
A pot experiment was performed to investigate As distribution in rice tissues and the functional microbial communities in soil when the sMFC was installed. The As in the soil porewater and rice plant parts were analyzed. 16S rRNA sequencing and Quantitative PCR were used to examine the microbial community and to quantify the relative abundance of As resistance genes in the rhizosphere, respectively.
The results suggest that the sMFC can simultaneously work as an electricity generator and As mitigator. The total As concentrations in the stems, leaves, husks, and rice grains were significantly decreased by 53.4%, 44.7%, 62.6%, and 67.9%, respectively in the plants with sMFC compared to the control. This decrease in As accumulation in the sMFC treatment may be explained by the decrease in the soil porewater dissolve organic matter content and abundance of As reducing gene (arsC). Moreover, known As reducing classes such as Clostridia, Bacilli and Thermoleophilia were significantly enhanced in the control treatment.
Integrating the sMFC in rice paddy soil offers a promising way to mitigate As accumulation in rice tissue and reduce dietary As exposure, while simultaneously producing electricity.
KeywordsRice Soil microbial fuel cell Arsenic Dissolve organic matter Iron
This work was supported by the National Science Foundation of China (41571305) and Jiangsu Science and Technology Program (BK20161251). The authors acknowledge the kind help of Xiao Zhou and Yi-Li Cheng for their technical support in the sample analysis. The authors are grateful to Elmer Villanueva, Xu Rong and Sun Jing for their help in the statistical, figure drawing and bacterial data analysis, respectively. We also thank Markus Klingelfuss and Jacquelin St. Jean for proof reading the manuscript.
- Chen C, Huang K, Xie WY, Chen SH, Tang Z, Zhao FJ (2017) Microbial processes mediating the evolution of methylarsine gases from dimethylarsenate in paddy soils. Environmental Science & Technology 51(22):13190–13198Google Scholar
- Gustave W, Yuan Z-F, Sekar R, Ren Y-X, Chang H-C, Liu J-Y, Chen Z (2019) The change in biotic and abiotic soil components influenced by paddy soil microbial fuel cells loaded. J Soils Sediments 19(1):106–115Google Scholar
- Habibul N, Hu Y, Wang YK, Chen W, Yu HQ, Sheng GP (2016b) Bioelectrochemical chromium (VI) removal in plant-microbial fuel cells. Environ Sci Technol 50(7):3882–3889Google Scholar
- Li B, Zhou S, Wei D, Long J, Peng L, Tie B, Williams PN, Lei MJSTTE (2019) Mitigating arsenic accumulation in rice (Oryza sativa L.) from typical arsenic contaminated paddy soil of southern China using nanostructured α-MnO2: pot experiment and field application. Sci Total Environ 650:546–556CrossRefGoogle Scholar
- Liu B, Ji M, Zhai H (2018) Anodic potentials, electricity generation and bacterial community as affected by plant roots in sediment microbial fuel cell: effects of anode locations. Chemosphere 209:739–747Google Scholar
- Mirza BS, Muruganadam S, Meng X, Sorensen DL, Dupont RR, McLean JE (2014) Arsenic (V) reduction in relation to iron (III) transformation and molecular characterization of the structural and functional microbial community in sediments of a basin-fill aquifer in Northern Utah. Appl Environ Microbiol 80(10):3198–3208Google Scholar
- Sahrawat K (2005) Iron toxicity in wetland rice and the role of other nutrients. J Plant Nutr Soil Sci 27:1471–1504Google Scholar
- Slyemi D, Bonnefoy V (2012) How prokaryotes deal with arsenic. Environ Microbiol Rep 4:571–586Google Scholar