BIORESOURCE TECHNOLOGY
·
2023
·
IF 11.4
Xiaolu Li,Yin Liu,Xuyao Li,Zhiyi Qin,Yu Su,Stefano Freguia,Leiyu Feng,Yinguang Chen
The influence of phenanthrene (PHE), a general polycyclic aromatic hydrocarbon in waste activated sludge, on sludge alkaline dark fermentation for hydrogen accumulation was investigated prospectively. The yield of hydrogen was 16.2 mL/g TSS with 50 mg/kg TSS PHE, which was 1.3-fold greater than that of the control. Mechanism research demonstrated that hydrogen production and the abundance of functional microorganisms were facilitated, whereas those of homoacetogenesis were reduced. The activity of pyruvate ferredoxin oxidoreductase in the conversion of pyruvate to reduced ferredoxin for hydrogen production was promoted by 57.2%, and that of carbon monoxide dehydrogenase and formyltetrahydrofolate synthetase, closely associated with hydrogen consumption, was suppressed by 60.5% and 55.9%, respectively. Moreover, the encoding genes involved in pyruvate metabolism were significantly up-regulated, while genes related to consuming hydrogen to reduce carbon dioxide and produce 5-methyltetrahydrofolate were down-regulated. This study notably illustrates the effect of PHE on hydrogen accumulation from metabolic pathways.
研究领域:
环境科学
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Xiaoshi Cheng,Le Zhang,Zhicheng Wei,Xinyi Liu,Xiong Shi,Xuran Liu,Jiashun Cao,Qian Feng,Fang Fang,Jingyang Luo
Sludge anaerobic fermentation is a pivotal route to transit wastewater treatment plants towards energy-neutral and resource recovery-oriented plants, while the overall efficiency is commonly restrained by co-exist contaminants. This study unveiled the cooperative effect of sulfadiazine (SDZ) and linear alkylbenzene sulfonates (LAS) in driving volatile fatty acids (VFAs) biosynthesis during waste activated sludge (WAS) anaerobic fermentation. The VFAs remarkably elevated to 1189 mg COD/L in LAS/SDZ, which was approximately 1.3–3.2 folds of SDZ and LAS. SDZ and LAS synergistically disintegrated extracellular polymeric substances to provide fermentation substrates. These changes altered microbial population and enhanced microbial networks interconnection. Moreover, the proteins released from WAS might facilitate electron transfer among microorganisms. The functional anaerobic species, including hydrolytic-acidogenic bacteria ( e.g. , Veillonellaceae and Lactobacillus ) and electroactive bacteria ( e.g ., Parabacteroides and Fonticella ), were enriched. Also, the metabolic traits responsible for transmembrane transport, intracellular metabolism, VFAs biosynthesis and electron transfer-related process were strengthened with the upregulation of functional genes. Further analysis revealed that the functional anaerobic species activated quorum sensing and two-component systems to counteract unfavorable LAS/SDZ stress and maintain high metabolic activities. This work elucidated the overlooked roles of substrates in modulating anaerobic consortia and metabolic traits in sludge fermentation systems with mixed pollutants stressing.
研究领域:
环境科学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 29
·24236-24244
·
IF 3.289
Bao Yu,Xiaoting Huang,Dongling Zhang,Ziyang Lou,Haiping Yuan,Nanwen Zhu
The effects of nano zero-valent iron (NZVI) on sludge anaerobic digestion were investigated from the perspective of the sludge fermentation liquor (SFL) and microbial community structure. Compared with micrometer-scale ZVI, NZVI exhibited a considerable inhibition in methane production during the initial 6 days while the negative effect attenuated subsequently and methane production recovered. Similar to micrometer-scale ZVI, enhanced methane production (108.24 mL per gVS) was obtained with NZVI addition, and increased by 46.1% compared to no-ZVI assay. The results indicated that NZVI could promote hydrolysis-acidification with inhibited conversion of acetic acid to methane in the initial stage, which could be ascribed to the high H2 partial pressure. The rapid dissolution of NZVI hindered the phosphorus uptake by methanogens, meanwhile the more reductive atmosphere contributed to the degradation of propionic acid. Further investigations on SFL showed that NZVI could facilitate the release of biodegradable compounds without propionic acid accumulation, creating a favorable substrate environment for methanogens. The bacteria and archaea community structure involved in methane production was studied. Results indicated that NZVI could enhance hydrogenotrophic methanogenesis with the highest relative abundances of Clostridia (53.2%) and Methanosarcina (22.6%) among the assays.
研究领域:
环境科学
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微生物学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Changzheng Fan,Man Zhou,Xiang Tang,Guangming Zeng,Qiuxiang Xu,Biao Song,Rui Gong,Baowei Zhang,Weiping Xiong,Yue Lu,Haoran Dong,Ning Ding,Zhili Luo,Lingyu Wang,Jiaqi Wei
Triclosan (TCS) is an emerging contaminant in waste activated sludge (WAS). However, the effects of TCS on WAS anaerobic fermentation is still unknown. Herein, we investigated the impacts of different TCS levels on the short-chain fatty acid (SCFA) accumulation. TCS at 100 mg/kg TSS (total suspended solids) significantly (p < 0.05) enhanced SCFA production by 35.8 ± 4.1% through increasing the production of propionic and butyric acid, while the higher TCS level inhibited the SCFA production processes. The results of batch tests with real sludge showed that 100 mg/kg TSS TCS enhanced acidogenesis process and had no significant impact on other processes, while higher TCS level caused negative effects on acidogenesis, acetogenesis and methanogenesis. Generally, 2,4-dichlorophenol was considered as the main metabolic product of TCS under anaerobic condition. However, in this study, TCS was found to be converted into (Z)-4-(2,4-dichlorophenoxy)penta-1,3-dien-3-ol, 2,4-dichloro-1-(4-chloro-2-methoxyphenoxy)benzene and other substances, and its hypothetical metabolic pathway were reformulated. The microbial community structure in the WAS anaerobic fermentation system did not significantly change with TCS addition, but 100 mg/kg TSS TCS contributed to the modest enrichment of SCFA producers. Further analyses of key enzyme activity and abundance of enzyme-encoded genes revealed that TCS at 100 mg/kg TSS up-regulated the expression of enzyme-coding genes (i.e. butyrate kinase (BK) and oxaloacetic acid carboxylase (OAATC)), and this is the primary reason for the increased SCFA production. This work provides a new insight for pollutant effects in WAS anaerobic fermentation, which will help to reveal the impact of emerging contaminants and relearn the role of conventional pollutants.
研究领域:
环境工程
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微生物学
·
废物管理
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2021
·
IF 9.642
Jingyang Luo,Le Zhang,Wei Du,Xiaoshi Cheng,Fang Fang,Jiashun Cao,Yang Wu,Yinglong Su
T his work revealed the impacts of exogeneous allicins on the antibiotic resistance genes (ARGs) variations during waste activated sludge (WAS) fermentation process. The overall abundance of ARGs was respectively reduced by 4.84 and 9.42% in presence of 0.01 and 0.05 g allicin/g TSS. Allicins disrupted the EPS structure and increased the permeability of cell membranes, which resulted in the release of ARGs for subsequent removal. Allicins also reduced intracellular ATP levels, which was disadvantageous to ARGs dissemination. Besides, allicins affected the microbial community and decreased the abundance of potential hosts based on bacterial taxa-ARGs network analysis. Moreover, the metabolic pathways and genetic expressions ( i.e., two-component system, quorum sensing, and SOS response) involved in ARGs propagation were down-regulated, which caused the ARGs alleviation in allicins-stressed reactors. Overall, the simultaneous responses of cellular status, bacterial host, and genetic regulation accounted for the effective ARGs reduction induced by allicins during WAS fermentation.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Jingyang Luo,Xiaoshi Cheng,Yinglong Su,Le Zhang,Wei Du,Xingchen Bao,Wenxuan Huang,Qian Feng,Jiashun Cao,Yang Wu
Waste activated sludge (WAS) is an important reservoir of antibiotic resistance genes (ARGs). However, the interactive effects of co-existed substances in WAS on ARGs fates have yet to be disclosed. This study demonstrated the type-dependent effects of surfactants (potentially effective chemicals for WAS disposal) on the reduction of ARGs during WAS fermentation, which followed the order of linear alkylbenzene sulphonates (LAS) > alkyl polyglucoside (APG) > hexadecyl trimethyl ammonium bromide (HTAB). Interestingly, the ratio of ARGs affiliated to efflux pump showed an upward trend in the surfactant-treated reactor. Mechanistic investigations revealed that the extracellular polymeric substances (EPS) destruction induced by surfactants increased the permeability of bacterial cells and caused the ARGs being released and susceptible for subsequent elimination. Besides, the surfactants significantly altered the microbial community , resulting in the ARGs reduction via changing the potential hosts. Also, the metabolic pathways participated in the dissemination of ARGs were remarkably down-regulated, thereby resulting in the reduction of ARGs abundances. This work broadened the understanding of ARGs fates during WAS fermentation and provided insights on the interactive functions of exogenous chemicals in multiple matrics.
研究领域:
环境科学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2020
·
IF 7.539
Jingyang Luo,Wenxuan Huang,Qin Zhang,Wen Guo,Yang Wu,Qian Feng,Fang Fang,Jiashun Cao,Yinglong Su
The effects of different hypochlorite types (namely Ca(OCl) 2 and NaOCl) on the waste activated sludge (WAS) anaerobic fermentation, and microbial community and activity were investigated. The results indicated that both Ca(OCl) 2 and NaOCl contributed to volatile fatty acids (VFAs) production by simultaneously enhancing the solubilization, hydrolysis and acidification processes. The maximal VFAs was respectively 1379.5 (at 10 d) and 1621.5 (at 8 d) mg COD/L at the optimal dose of NaOCl and Ca(OCl) 2 while it was merely 157.4 (at 6 d) mg COD/L in the control. However, the Ca(OCl) 2 might affect the anaerobic process in a continuous mode while the NaOCl was relatively transient, which caused distinctive influences on the microbial structure and activity, and subsequently VFAs production in WAS fermentation systems. Moreover, Ca(OCl) 2 treatments showed advantages over NaOCl on WAS dewatering and VSS reduction, implying the superiority of utilizing Ca(OCl) 2 as additives for WAS disposal.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Jingyang Luo,Wangbei Cao,Wen Guo,Shiyu Fang,Wenxuan Huang,Feng Wang,Xiaoshi Cheng,Wei Du,Jiashun Cao,Qian Feng,Yang Wu
Various pollutants commonly co-exist in the waste active sludge (WAS), but the interactive effects and mechanisms of co-occurrence pollutants on the WAS treatment remain unclear. This work mainly investigated the impacts of different surfactants ( i.e., HTAB and SDBS) and CeO 2 nanoparticles (NPs) co-occurrence on the WAS fermentation for short-chain fatty acids (SCFAs) production, and found that the CeO 2 NPs coexisting with surfactants caused antagonistic effects on the SCFAs generation (10.7% and 33.9% inhibition by HTAB and SDBS , respectively). The surfactants and CeO 2 NPs co-occurrence restrained the solubilization , hydrolysis , and acidification steps simultaneously. Moreover, the functional hydrolytic-acidogenic bacterial ( e.g., Haliangium and Bacteroidetes sp. ) and the microbial metabolic networks involved in extracellular hydrolysis ( e.g., pepd and NEU1 ), substrate metabolism ( e.g., ALDO and asdA ), and fatty acid biosynthesis ( e.g. , aarC and pct ) were all downregulated by 4.3–53.8% in the reactors with surfactants and CeO 2 NPs co-occurrence. The presence of surfactants enhanced the dispersibility and stability of CeO 2 NPs and the Ce dissolution (1.5–3.0 times higher). Also, surfactants contributed to the WAS disintegration, which could improve the interactive chances of microorganisms entrapped in WAS and CeO 2 NPs by promoting the transportation channels, and therefore aggravated the toxicity towards anaerobic species.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zhipeng Zhang,Rui Liu,Wei Zheng,Yaqiong Lan,Yongmei Li,Lujun Chen
In this study, a ternary co-fermentation system was developed using iron-phosphorus precipitates (FePs)-bearing sludge, peroxydisulfate (PDS), and corn gluten meal (CGM) to activate PDS through a microbe-mediated endogenous iron cycle, thereby promoting phosphorus (P) release and acidogenesis. Fe(II) was released along with P via the dissolution of Fe(II)Ps, resulting from Fe(III)Ps bioreduction. Subsequently, the released Fe(II) induced PDS activation, which avoided the negative impact of external activators on P release by precipitation with P. The optimal PDS dosage for ternary co-fermentation was 0.2 mM/g TSS. At this dosage, P release efficiency increased from 27.3 % (sludge-only group) to 71.6 % and volatile fatty acids (VFAs) production increased from 41.0 (sludge-only group) to 158.5 mg COD/g VSS. SO 4 ·− and ·OH generated through PDS activation disintegrated sludge flocs to promote encapsulated Fe(II)Ps dissolution and organics release. The concentration of soluble chemical oxygen demand in the sludge-CGM-PDS group was 4.4 times greater than that in the sludge-only group. The increased content and biodegradability of hydrolysates (e.g., protein-like, tryptophan-like, and tyrosine-like substances) contributed to the enrichment of hydrolytic-acidogenic bacteria, resulting in a relative abundance of 40.7 %. Unclassified_c__Ignavibacteria , Clostridium , and Rubrivivax were the dominant hydrolytic-acidogenic biomarkers, which enhanced the intracellular metabolisms of glycolysis, amino acid degradation, and acetogenesis, leading to notable increases in VFAs yields. The relative abundance of phosphate acetyltransferase, a key enzyme in acetate biosynthesis, increased by 8.9 %, thus facilitating acetogenesis. In addition, unclassified_c__Ignavibacteria , as putative iron reducers, were the primary microbes mediating endogenous iron reduction. This study provides valuable insights into the PDS self-activation mechanism and microfloral traits during ternary co-fermentation, contributing to the valorization of FePs-bearing sludge waste.
研究领域:
环境工程
·
微生物学
·
废水处理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Jingyang Luo,Wenxuan Huang,Qin Zhang,Yang Wu,Fang Fang,Jiashun Cao,Yinglong Su
The effectiveness of hypochlorites (NaClO and Ca(ClO) 2 ) on the reduction of antibiotic resistance genes (ARGs) during waste activated sludge (WAS) fermentation was determined by the quantitative PCR. NaClO and Ca(ClO) 2 exhibited distinct effects on ARGs fates. Ca(ClO) 2 was effective in removing all investigated ARGs, and the efficiency was highly dose-dependent. Unexpectedly, the NaClO treatment attenuated ARGs with lower efficiency and even caused the propagation of certain ARGs (i.e . , aad A1 and tet Q) at higher doses. The extracellular polymeric substances dissolution and membrane integrity suggested that unstable NaClO had acute effects on bacteria initially, while it was ineffective to further attenuate ARGs released from hosts due to the rapid consumption of oxidative ClO - . Without lasting and strong oxidative stress , the microbial activities of tolerant ARGs hosts will partially recover and then contribute to the ARGs dissemination across genera. In contrast, solid-state Ca(ClO) 2 was slowly released and exhibited prolonged effects on bacteria by disrupting cell membranes and removing the susceptible ARGs released from hosts. Furthermore, bacterial taxa-ARG network analysis indicated that Ca(ClO) 2 reduced the abundance of potential hosts, and the metabolic pathway and gene expression related to ARGs propagation were significantly downregulated by Ca(ClO) 2 , which contributed to efficient ARGs attenuation.
研究领域:
环境工程
·
微生物学
·
遗传学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2021
·
IF 11.236
Chen Cai,Xuesong Hui,Wan Yang,Yu Hua,Huiling Liu,Xiaohu Dai
Thermal hydrolysis pretreatment (THP) can effectively remove the antibiotic resistance genes (ARGs) from sewage sludge, but the rebounding effects in the subsequent anaerobic fermentation are often observed. The purpose of this study was to elucidate the distribution and fate of intracellular and extracellular ARGs (iARGs and eARGs) in the sludge acidogenic fermentation process coupled with THP. Our results revealed that THP significantly reduced the absolute abundance of total ARGs in raw sludge but increased eARGs by 0.3–1.4 log units under practical conditions (140 °C for 30 min). There is no significant difference in the removal of total ARGs between the two acidogenic fermenters receiving raw and hydrolyzed sludge, with iARGs prevailing in the produced biosolids. The succession of bacterial community and the co-occurrence relationships among ARG type, mobile genetic elements and bacterial taxa were observed, suggesting a phylogenetic basis for the iARGs patterns in fermented sludge. However, eARGs were susceptible to biodegradation with a half-life of 2.34 h and they contributed limitedly to the ARGs propagation through transformation. These findings suggest an emphasis on the mitigation of iARGs during the acidogenic fermentation of sludge, which would be achieved by lowering the richness and physicochemical destruction of potential hosts.
研究领域:
环境科学
·
微生物学
·
废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）