Dataset Information

Microbial community regulation and performance enhancement in gas biofilters by interrupting bacterial communication.

ABSTRACT:

Background

Controlling excess biomass accumulation and clogging is important for maintaining the performance of gas biofilters and reducing energy consumption. Interruption of bacterial communication (quorum quenching) can modulate gene expression and alter biofilm properties. However, whether the problem of excess biomass accumulation in gas biofilters can be addressed by interrupting bacterial communication remains unknown.

Results

In this study, parallel laboratory-scale gas biofilters were operated with Rhodococcus sp. BH4 (QQBF) and without Rhodococcus sp. BH4 (BF) to explore the effects of quorum quenching (QQ) bacteria on biomass accumulation and clogging. QQBF showed lower biomass accumulation (109 kg/m³) and superior operational stability (85-96%) than BF (170 kg/m³; 63-92%) at the end of the operation. Compared to BF, the QQBF biofilm had lower adhesion strength and decreased extracellular polymeric substance production, leading to easier detachment of biomass from filler surface into the leachate. Meanwhile, the relative abundance of quorum sensing (QS)-related species was found to decrease from 67 (BF) to 56% (QQBF). The QS function genes were also found a lower relative abundance in QQBF, compared with BF. Moreover, although both biofilters presented aromatic compounds removal performance, the keystone species in QQBF played an important role in maintaining biofilm stability, while the keystone species in BF exhibited great potential for biofilm formation. Finally, the possible influencing mechanism of Rhodococcus sp. BH4 on biofilm adhesion was demonstrated. Overall, the results of this study achieved excess biomass control while maintaining stable biofiltration performance (without interrupting operation) and greatly promoted the use of QQ technology in bioreactors. Video Abstract.

SUBMITTER: Wang YC

PROVIDER: S-EPMC9484056 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Microbial community regulation and performance enhancement in gas biofilters by interrupting bacterial communication.

Wang Yong-Chao YC Lin Yu-Ting YT Wang Can C Tong Zhen Z Hu Xu-Rui XR Lv Ya-Hui YH Jiang Guan-Yu GY Han Meng-Fei MF Deng Ji-Guang JG Hsi Hsing-Cheng HC Lee Chung-Hak CH

Microbiome 20220919 1

<h4>Background</h4>Controlling excess biomass accumulation and clogging is important for maintaining the performance of gas biofilters and reducing energy consumption. Interruption of bacterial communication (quorum quenching) can modulate gene expression and alter biofilm properties. However, whether the problem of excess biomass accumulation in gas biofilters can be addressed by interrupting bacterial communication remains unknown.<h4>Results</h4>In this study, parallel laboratory-scale gas bi ...[more]

PMID: 36117217

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Dataset Information

Microbial community regulation and performance enhancement in gas biofilters by interrupting bacterial communication.

Background

Results

Publications

Microbial community regulation and performance enhancement in gas biofilters by interrupting bacterial communication.

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