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Mirabelle Perossi Cunha, Rafael Marçal Ferraz, Giselle Patrícia Sancinetti, Renata Piacentini Rodriguez
Acid mine drainage (AMD) is among the most serious threats to water and the typical alkali-based treatment costs are high. This study's main objective was the establishment of a highly efficient biological process using an upflow anaerobic sludge blanket (UASB) reactor to treat AMD based on a shorter hydraulic retention time (HRT) and lower organic matter input. The process was evaluated for a long-term operation (739 days) in terms of the influence of HRT (14-24 h), metal addition, sulfate loading rate (0...
November 8, 2018: Biodegradation
Oumaima Zouari, Didier Lecouturier, Alice Rochex, Gabrielle Chataigne, Pascal Dhulster, Philippe Jacques, Dhouha Ghribi
Pseudomonas strains isolated from oil contaminated soils were screened for biosurfactant production. Three out of eleven Pseudomonas isolates were selected for their high emulsifying activity (E24 value on n-hexadecane ~ 78%). These isolates (E39, E311 and E313) were identified as members of the P. putida group using phenotypical methods and a molecular approach. To identify the chemical nature of produced biosurfactants, thin layer chromatography and MALDI-ToF mass spectrometry analysis were carried out and revealed lipopeptides belonging to the syringafactin family...
November 2, 2018: Biodegradation
Yanling Ma, Yanpeng Li, Chao Huang, Yuexin Tian, Zhidan Hao
With the increasing public awareness of environmental pollution, surfactant-enhanced bioremediation has been emerged as a very promising strategy to clear up hydrophobic organic compounds (HOCs) contaminated soils. As a class of biosurfactants that has represented a suitable alternative to other chemically synthesized counterparts, rhamnolipids have been intensively applied in biological treatment of HOCs, for being environmentally friendly and having remarkable physicochemical properties associated with the contaminant removal...
October 24, 2018: Biodegradation
Rotem Golan, Faina Gelman, Tomasz Kuder, Alicia A Taylor, Zeev Ronen, Anat Bernstein
Anthropogenic activities have introduced elevated levels of brominated phenols to the environment. These compounds are associated with toxic and endocrine effects, and their environmental fate is of interest. An aerobic strain Ochrobactrum sp. HI1 was isolated from soils in the vicinity of a bromophenol production plant and tested for its ability to degrade 4-bromophenol (4-BP). A ring hydroxylation pathway of degradation was proposed, using the evidence from degradation intermediates analysis and multi-element (C, Br, H) compound-specific isotope analysis...
October 22, 2018: Biodegradation
Hale Ozgun
Anaerobic digestion of sludge is considered to be one of the most appropriate technologies for energy production via conversion of organic matter into methane containing biogas. Biogas produced by anaerobic digestion of municipal wastewater sludge can be utilized as fuel to offset heat and electricity consumption of wastewater treatment facilities. Modeling can be used effectively to evaluate the impact of different process and operation variables on the performance of the treatment processes including complex ones such as anaerobic digestion...
October 17, 2018: Biodegradation
Edinson Puentes-Cala, Jens Harder
The betaproteobacterium Castellaniella defragrans 65Phen grows on monoterpenes at concentrations toxic to many bacteria. Tolerance mechanisms include modifications of the membrane fatty acid composition and the mineralization of monoterpenes. In this study, we characterized an efflux transporter associated to the monoterpene metabolism. The inner-membrane transporter AmeD (apolar monoterpene efflux) affiliated to the HAE3 (hydrophobe/amphiphile efflux) family within the Resistance-Nodulation-Division (RND) superfamily...
October 17, 2018: Biodegradation
Anna-Lena Altenhoff, Jan de Witt, Rodrigo Andler, Alexander Steinbüchel
Much fundamental research has already been performed to understand the mechanism of microbial rubber degradation. Due to the increasing amount of rubber waste, biotechnical methods to degrade that particular waste are strongly needed. The present study evaluates whether a microbial or an enzymatic process is more suitable for efficient biodegradation, due to less sensitivity towards rubber additives. Therefore we investigated the impact of 15 different frequently used rubber additives on cells of the potent rubber degrader Gordonia polyisoprenivorans VH2 and the enzyme Lcp1VH2 ...
October 15, 2018: Biodegradation
Weihua Xu, Guofeng Duan, Yunguo Liu, Guangming Zeng, Xin Li, Jie Liang, Wei Zhang
Heavy metals-organics mixture pollution is increasingly concerned and simultaneous removal of organic pollutants and heavy metals is becoming significant. In this study, a strain was isolated from the sediment of a tannery effluent outfalls, which can remove o-dichlorobenzene (o-DCB) and Cr(VI) simultaneously. The bacterial isolate was identified as Serratia marcescens by the 16S rRNA gene sequences. The strain removed about 90% of o-DCB and more than 80% of Cr(VI) at the concentration of 1.29 g L-1 o-DCB and 20 mg L-1 Cr(VI)...
December 2018: Biodegradation
Zhoukun Shi, Weiliang Dong, Fengxue Xin, Jiawei Liu, Xinhai Zhou, Fanli Xu, Ziyao Lv, Jiangfeng Ma, Wenming Zhang, Yan Fang, Min Jiang
An acetamiprid-degrading fungus was isolated from contaminated soil and identified as Fusarium sp. strain CS-3 based on physiological, biochemical, and molecular analyses. Strain CS-3 exploited 50 mg/L as the sole carbon source in liquid culture, removing 98% in 96 h. Strain CS-3 retained its acetamiprid degradation abilities over a wide range of pH (5.0-8.0) and temperature (20-42 °C). HPLC-MS analysis showed that N'-[(6-chloropyridin-3-yl)methyl]-N-methylacetamide, 2-chloro-5-hydroxymethylpyridine, and 6-chloronicotinic acid were identified as the most predominant metabolites, forming the basis for a newly described acetamiprid degradation pathway...
December 2018: Biodegradation
Shuchan Peng, Xinkuan Han, Fuzhong Song, Lilan Zhang, Caiying Wei, Peili Lu, Daijun Zhang
A previous study demonstrated that denitrification synergized with Anammox could accelerate the anaerobic degradation of benzene. The inhibitory effects of benzene, toluene, phenol and benzoate in single and combination on Anammox activity were investigated by short-term batch tests. The results indicated that the inhibition of single compounds on Anammox could be well fitted with the extended non-competitive and Luong inhibition kinetic models. The inhibitions of the individual compound were in order as follows: benzene > toluene > phenol > benzoate...
December 2018: Biodegradation
A M Ferro Orozco, E M Contreras, N E Zaritzky
The objective of the present work was to analyze the interrelationship between the aerobic degradation of BPA and readily biodegradable substrates by activated sludge (AS) in semi-continuous reactors (SCRs). AS were obtained from three SCRs fed with glucose, acetate or peptone. AS from these reactors were used as inocula for three SCRs that were fed with each biogenic substrate, and for three SCRs that were fed with the biogenic substrate and BPA. In all cases, dissolved organic carbon (DOC), BPA, total suspended solids (TSS) and respirometric measurements were performed...
December 2018: Biodegradation
Malin Hultberg, Hristina Bodin
Recent research has demonstrated the potential of using filamentous fungi to form pellets with microalgae (biopellets), in order to facilitate harvesting of microalgae from water following algae-based treatment of wastewater. In parallel, there is a need to develop techniques for removing organic pollutants such as pesticides and pharmaceuticals from wastewater. In experiments using the microalga Chlorella vulgaris, the filamentous fungus Aspergillus niger and biopellets composed of these microorganisms, this study investigated whether fungal-assisted algal harvesting can also remove pesticides from contaminated water...
December 2018: Biodegradation
Zhenguo Chen, Xiaojun Wang, Xiaozhen Chen, Jing Chen, Xiaoyang Gu
Denitrifying granular sludge reactor holds better nitrogen removal efficiency than other kinds of denitrifying reactors, while this reactor commonly needs seeding anaerobic granular sludge and longer period for start-up in practice, which restricted the application of denitrifying granular sludge reactor. This study presented a rapid and stable start-up method for denitrifying granular sludge. An upflow sludge blanket (USB) reactor with packings was established with flocculent activated sludge for treatment of high concentration nitrite wastewater...
December 2018: Biodegradation
Ningke Hou, Yongzhen Xia, Xia Wang, Huaiwei Liu, Honglei Liu, Luying Xun
Many industrial activities produce H2 S, which is toxic at high levels and odorous at even very low levels. Chemolithotrophic sulfur-oxidizing bacteria are often used in its remediation. Recently, we have reported that many heterotrophic bacteria can use sulfide:quinone oxidoreductase and persulfide dioxygenase to oxidize H2 S to thiosulfate and sulfite. These bacteria may also potentially be used in H2 S biotreatment. Here we report how various heterotrophic bacteria with these enzymes were cultured with organic compounds and the cells were able to rapidly oxidize H2 S to zero-valence sulfur and thiosulfate, causing no apparent acidification...
December 2018: Biodegradation
Jie Tang, Bo Liu, Ting-Ting Chen, Kai Yao, Lin Zeng, Chao-Yi Zeng, Qing Zhang
A novel beta-cypermethrin (Beta-CP)-degrading strain isolated from activated sludge was identified as Brevibacillus parabrevis BCP-09 based on its morphological and physio-biochemical characteristics, and 16S rRNA gene analysis. Strain BCP-09 could effectively degrade Beta-CP at pH 5.0-9.0, 20-40 °C, and 10-500 mg L-1 Beta-CP. Under optimal conditions (pH 7.41, 38.9 °C, 30.9 mg L-1 Beta-CP), 75.87% Beta-CP was degraded within 3 days. Beta-CP degradation (half-life, 33.45 h) and strain BCP-09 growth were respectively described using first-order-kinetic and logistic-kinetic models...
December 2018: Biodegradation
Duc Danh Ha
Thauera sp. strain DKT isolated from sediment utilized 2,4-dichlorophenoxyacetic acid (2,4D) and its relative compounds as sole carbon and energy sources under anaerobic conditions and used nitrate as an electron acceptor. The determination of 2,4D utilization at different concentrations showed that the utilization curve fitted well with the Edward model with the maximum degradation rate as 0.017 ± 0.002 mM/day. The supplementation of cosubstrates (glucose, acetate, sucrose, humate and succinate) increased the degradation rates of all tested chemical substrates in both liquid and sediment slurry media...
October 2018: Biodegradation
Chang Ding, Lisa Alvarez-Cohen, Jianzhong He
The dechlorinating Dehalococcoides mccartyi species requires acetate as carbon source, but little is known on its growth under acetate limiting conditions. In this study, we observed growth and dechlorination of a D. mccartyi-containing mixed consortium in a fixed-carbon-free medium with trichloroethene in the aqueous phase and H2 /CO2 in the headspace. Around 4 mM formate was produced by day 40, while acetate was constantly below 0.05 mM. Microbial community analysis of the consortium revealed dominance by D...
October 2018: Biodegradation
Melanie C Bruckberger, Trevor P Bastow, Matthew J Morgan, Deirdre Gleeson, Natasha Banning, Greg Davis, Geoffrey J Puzon
Once released into the environment, petroleum is exposed to biological and physical weathering processes which can lead to the formation and accumulation of highly recalcitrant polar compounds. These polar compounds are often challenging to analyse and can be present as an "unresolved complex mixture" (UCM) in total petroleum hydrocarbon (TPH) analyses and can be mistaken for natural organic matter. Existing research on UCMs comprised of polar compounds is limited, with a majority of the compounds remaining unidentified and their long-term persistence unknown...
October 2018: Biodegradation
Lijuan Feng, Rong Jia, Zhen Zeng, Guangfeng Yang, Xiangyang Xu
To enhance the startup and efficient simultaneous nitrification and denitrification for sewage treatment, sequencing batch biofilm reactors (SBBRs) partially coupled with rice husk were established and operated under various intermittent micro-aeration cycles (IMCs) and COD/N ratios under oxygen-limiting intermittent aeration conditions. Experimental results showed that the increase of IMCs with non-aeration/micro-aeration mode of (8 h/4 h)1 to (2 h/1 h)4 in a 12 h-cycle accelerated the startup performance and improved NH4 + -N and COD removal...
October 2018: Biodegradation
E Emilia Rios-Del Toro, Edgardo I Valenzuela, Nguyen E López-Lozano, M Guadalupe Cortés-Martínez, Miguel A Sánchez-Rodríguez, Omar Calvario-Martínez, Salvador Sánchez-Carrillo, Francisco J Cervantes
Availability of fixed nitrogen is a pivotal driver on primary productivity in the oceans, thus the identification of key processes triggering nitrogen losses from these ecosystems is of major importance as they affect ecosystems function and consequently global biogeochemical cycles. Denitrification and anaerobic ammonium oxidation coupled to nitrite reduction (Anammox) are the only identified marine sinks for fixed nitrogen. The present study provides evidence indicating that anaerobic ammonium oxidation coupled to the reduction of sulfate, the most abundant electron acceptor present in the oceans, prevails in marine sediments...
October 2018: Biodegradation
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