Long-term effects of multi-walled carbon nanotubes on the performance and microbial community structures of an anaerobic granular sludge system

The expanded granular sludge blanket reactor (EGSB) was operated for 198 days to study the long-term effects of phenanthrene (PHE) enrichment on system performance and microbial community. The results showed that the PHE was significantly enriched in the reactor. The final PHE concentration in effluent and sludge reached to 1.764±0.05 mg/L and 12.52±0.42 mg/gTS, respectively. While the average daily methane production was decreased by 5.0%-9.8% under long-term PHE exposure. The 3D-EEM of effluent indicated that PHE stimulated the microbial metabolism with the higher intensity of soluble microbial byproduct-like materials (SMP) and proteins. Moreover, the removal efficiency of soluble chemical oxygen demand (SCOD) and NH4+-N gradually diminished with the enrichment of PHE. PHE shaped the microbial community, and the predominant fermentative bacteria (Mesotoga) was severely inhibited. Contrarily, the bacteria (Syntrophorhabdus, Acinetobacter, Desulfovibrio, Desulfomicrobium) involved in PHE-degradation was enriched at end of Phase V. In addition, the relative abundance (RA) of hydrotrophic methanogens (Methanofastidiosum, Methanolinea, Methanobacterium, Methanomassiliicoccus) increased by 0.96-fold with the long-term enrichment of PHE, while the RA of acetoclastic Methanosaeta obviously decreased.

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When nanoparticle and microbes meet: The effect of multi-walled carbon nanotubes on microbial community and nutrient cycling in hyperaccumulator system

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2021.126947 ◽

2021 ◽

pp. 126947

Author(s):

Xunfeng Chen ◽

Juncai Wang ◽

Yimin You ◽

Renyuan Wang ◽

Shaohua Chu ◽

...

Keyword(s):

Carbon Nanotubes ◽

Microbial Community ◽

Nutrient Cycling ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Long-term use of green manure legume and chemical fertiliser affect soil bacterial community structures but not the rate of soil nitrate decrease when excess carbon and nitrogen are applied

Soil Research ◽

10.1071/sr17109 ◽

2017 ◽

Vol 55 (6) ◽

pp. 524 ◽

Cited By ~ 6

Author(s):

Misato Toda ◽

Yoshitaka Uchida

Keyword(s):

Microbial Community ◽

Rice Straw ◽

Soil Microbial Community ◽

Green Manure ◽

Community Structures ◽

Hairy Vetch ◽

Soil Microbial ◽

Microbial Community Structures ◽

Chemical Fertiliser

Legumes add not only nitrogen (N), but also carbon (C) to soils, so their effects on the soil microbial community may be different from those of chemical fertiliser. Soil microbes often compete with plants for N when excess C is applied due to their increased N immobilisation potentials and denitrification. In the present study we evaluated the effects of the 9-year use of a green manure legume (hairy vetch; Vicia villosa) in a greenhouse tomato system on soil microbial community structures as well as on the decrease of nitrate when rice straw was incorporated into the soil. Soil microbial community structures and their diversity were altered by the long-term use of legumes. The ratios of Acidobacteria, Gemmatimonadetes and Proteobacteria increased in the hairy vetch soils. The rates of decrease in nitrate were similar in soils with a history of chemical fertiliser and hairy vetch, following the addition of rice straw. In addition, during incubation with added rice straw, the difference between the two soil microbial community structures became less clear within 2 weeks. Thus, we conclude that even though growing a green manure legume changed soil bacterial community structures, this did not result in relatively faster loss of available N for plants when rice straw was added to the soils.

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Activated sludge microbial community responses to single-walled carbon nanotubes: community structure does matter

Water Science & Technology ◽

10.2166/wst.2015.095 ◽

2015 ◽

Vol 71 (8) ◽

pp. 1235-1240 ◽

Cited By ~ 6

Author(s):

Qiao Ma ◽

Yuanyuan Qu ◽

Wenli Shen ◽

Jingwei Wang ◽

Zhaojing Zhang ◽

...

Keyword(s):

Carbon Nanotubes ◽

Microbial Community ◽

Activated Sludge ◽

High Throughput Sequencing ◽

Alpha Diversity ◽

Single Walled Carbon Nanotubes ◽

Community Structures ◽

Single Walled Carbon ◽

Microbial Responses ◽

Walled Carbon Nanotubes

The ecological effects of carbon nanotubes (CNTs) have been a worldwide research focus due to their extensive release and accumulation in environment. Activated sludge acting as an important gathering place will inevitably encounter and interact with CNTs, while the microbial responses have been rarely investigated. Herein, the activated sludges from six wastewater treatment plants were acclimated and treated with single-walled carbon nanotubes (SWCNTs) under identical conditions. Illumina high-throughput sequencing was applied to in-depth analyze microbial changes and results showed SWCNTs differently perturbed the alpha diversity of the six groups (one increase, two decrease, three no change). Furthermore, the microbial community structures were shifted, and specific bacterial performance in each group was different. Since the environmental and operational factors were identical in each group, it could be concluded that microbial responses to SWCNTs were highly depended on the original community structures.

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