Unveiling the inhibition of chlortetracycline photodegradation and the increase of toxicity when coexisting with silver nanoparticles.

Silver nanoparticles (AgNPs) and antibiotics inevitably co-exist in water environment. Nonetheless, little is known regarding the interactions between AgNPs and antibiotics or the effects of AgNPs on environmental behavior of antibiotics, particularly on sunlight-driven transformation. In the present work, we found that AgNPs obviously inhibit the photochemical decay of chlortetracycline (CTC), and CTC boosts the dissolution of AgNPs.

Effect of Seed Sludge Type on Aerobic Granulation, Pollutant Removal and Microbial Community in a Sequencing Batch Reactor Treating Real Textile Wastewater.

The aerobic granulation, pollutant removal, and microbial community in real textile wastewater (TWW) treatment were compared using conventional activated sludge (CAS) and preformed aerobic granular sludge (AGS) in synthetic wastewater as seed in two reactors, reactor-1 (R1) and reactor-2 (R2), respectively. The results showed that complete granulation was achieved in R1 (sludge volume index at 5 min (SVI) and 30 min (SVI): 19.4 mL/g; granule size: 210 μm) within 65 days, while it only required 28 days in R2 (SVI and SVI: 27.

Optimization of bacterial cytokine protein production by response surface methodology for environmental bioremediation.

In natural and engineered systems, most microorganisms would enter a state of dormancy termed as "viable but non-culturable" (VBNC) state when they are exposed to unpredictable environmental stress. One of the major advances in resuscitating from such a state is the discovery of a kind of bacterial cytokine protein called resuscitation-promoting factor (Rpf), which is secreted from . In this study, the optimization of Rpf production was investigated by the response surface methodology (RSM).

Effective partial denitrification of biological effluent of landfill leachate for Anammox process: Start-up, influencing factors and stable operation.

Partial denitrification combined with Anammox is a promising approach for simultaneous removal of ammonium and nitrate from wastewaters. In this study, the start-up, influencing factors and stable operation of partial denitrification for treating biological effluent from landfill leachate were investigated. High nitrate loads (3.

Aerobic degradation of 3,3',4,4'-tetrachlorobiphenyl by a resuscitated strain Castellaniella sp. SPC4: Kinetics model and pathway for biodegradation.

Resuscitated strains which were obtained by addition of resuscitation promoting factor (Rpf) could provide a vast majority of microbial source for obtaining highly efficient polychlorinated biphenyl (PCB)-degrading bacteria. In this study, the Castellaniella sp. strain SPC4 which was resuscitated by Rpf addition showed the highest efficiency in degradation of 3,3',4,4'-tetrachlorobiphenyl (PCB 77) among the resuscitated and non-resuscitated isolates.

Characterization of a pH-Tolerant Strain sp. SASS1 and Its Phenol Degradation Performance Under Salinity Condition.

Biological treatment of complex saline phenolic wastewater remains a great challenge due to the low activity of bacterial populations under stressful conditions. Acid mine drainage (AMD) as a typically extreme environment, shaped unique AMD microbial communities. Microorganisms survived in the AMD environment have evolved various mechanisms of resistance to low pH, high salinity and toxic heavy metals.

Bacterial community shifts evaluation in the sediments of Puyang River and its nitrogen removal capabilities exploration by resuscitation promoting factor.

Identifying indigenous bacterial community and exploring the potential of native microorganisms are crucial for in situ bioremediation of nitrogenous pollutants in water bodies. This study evaluated the bacterial communities of sediment samples from a nitrogen polluted river, and revealed the possible environmental factors shaping the bacterial populations. Importantly, viable but non-culturable bacteria which possessed nitrogen removal capabilities in indigenous population of the sediments were explored by resuscitation promoting factor (Rpf).

Study on new artificial floating island removing pollutants.

In this study, two types of artificial floating islands (AFIs), group A (consists of 1# and 2# traditional AFIs with plant and soil) and group B (consists of 4# and 5# new-type AFIs with plant, substrate, and with luffa sponge and corncob hanging at the bottom), were constructed, respectively. The removal effects and degradation mechanisms of luffa sponge and corncob in group B were compared and investigated. Plant height, root growth, and packing degradation of the two types of AFIs were studied.

Sustainable biodegradation of phenol by immobilized Bacillus sp. SAS19 with porous carbonaceous gels as carriers.

In this study, high-efficient phenol-degrading bacterium Bacillus sp. SAS19 which was isolated from activated sludge by resuscitation-promoting factor (Rpf) addition, were immobilized on porous carbonaceous gels (CGs) for phenol degradation. The phenol-degrading capabilities of free and immobilized Bacillus sp.

Resuscitation of functional bacterial community for enhancing biodegradation of phenol under high salinity conditions based on Rpf.

This study assumed that key degraders of functional bacterial community were prone to enter into the viable but non-culturable (VBNC) state under high saline phenolic conditions, and resuscitation-promoting factor (Rpf) could strengthen these degraders for better performances. Based on these assumptions, Rpf was used to enhance salt-tolerant phenol-degrading capability of functional populations in activated sludge. Results suggested that Rpf accelerated the start-up process during sludge domestication, and significantly enhanced salt-tolerant phenol-degrading capability.

A New Approach of Rpf Addition to Explore Bacterial Consortium for Enhanced Phenol Degradation Under High Salinity Conditions.

Only a small fraction of salt-tolerant phenol-degrading bacteria can be isolated by conventional plate separation methods, because most bacteria in nature are in a viable but non-culturable (VBNC) state. The aims of this study were to screen out more effective functional bacteria using resuscitation-promoting factor (Rpf), and to determine whether a mixed bacterial consortium possesses better phenol-degrading capabilities under high salinity conditions. The results indicated that three strains unique to treatment group with Rpf addition were obtained.

Resuscitation of viable but non-culturable bacteria to enhance the cellulose-degrading capability of bacterial community in composting.

Nowadays, much of what we know regarding the isolated cellulolytic bacteria comes from the conventional plate separation techniques. However, the culturability of many bacterial species is controlled by resuscitation-promoting factors (Rpfs) due to entering a viable but non-culturable (VBNC) state. Therefore, in this study, Rpf from Micrococcus luteus was added in the culture medium to evaluate its role in bacterial isolation and enhanced effects on cellulose-degrading capability of bacterial community in the compost.

Effect of Metal Ions on the Formation of Trichloronitromethane during Chlorination of Catechol and Nitrite.

Catechol, nitrite, and dissolved metals are ubiquitous in source drinking water. Catechol and nitrite have been identified as precursors for halonitromethanes (HNMs), but the effect of metal ions on HNM formation during chlorination remains unclear. The main objective of this study was to investigate the effect of metal ions (Fe, Ti, Al) on the formation of trichloronitromethane (TCNM) (the most representative HNM species in disinfected water) on chlorinating catechol and nitrite.

A new approach to construct three-dimensional surface morphology of sludge flocs in a membrane bioreactor.

In this paper, a novel approach to construct three-dimensional (3D) surface morphology of sludge flocs in a membrane bioreactor (MBR) was proposed. The new approach combined the static light scattering method for fractal dimension (Df) determination with the modified two-variable Weierstrass-Mandelbrot (WM) function based on fractal geometry and coordinate transformation for spherical surface construction. It was found that the sludge flocs in the MBR showed apparent fractal characteristics.

Influences of acid-base property of membrane on interfacial interactions related with membrane fouling in a membrane bioreactor based on thermodynamic assessment.

Failure of membrane hydrophobicity in predicting membrane fouling requires a more reliable indicator. In this study, influences of membrane acid base (AB) property on interfacial interactions in two different interaction scenarios in a submerged membrane bioreactor (MBR) were studied according to thermodynamic approaches. It was found that both the polyvinylidene fluoride (PVDF) membrane and foulant samples in the MBR had relatively high electron donor (γ(-)) component and low electron acceptor (γ(+)) component.

Quantitative assessment of interfacial interactions with rough membrane surface and its implications for membrane selection and fabrication in a MBR.

The interfacial interactions between a foulant particle and rough membrane surface in a submerged membrane bioreactor (MBR) were quantitatively assessed by using a new-developed method. It was found that the profile of total interaction versus separation distance was complicated. There were an energy barrier and two negative energy ranges in the profile.

A novel approach for quantitative evaluation of the physicochemical interactions between rough membrane surface and sludge foulants in a submerged membrane bioreactor.

This study proposed a novel approach for quantitative evaluation of the physicochemical interactions between a particle and rough surface. The approach adopts the composite Simpson's rule to numerically calculate the double integrals in the surface element integration of these physicochemical interactions. The calculation could be achieved by a MATLAB program based on this approach.

The sorption of pentachlorophenol by aged sediment supplemented with black carbon produced from rice straw and fly ash.

Black carbon (BC) is a potential material for controlling hydrophobic organic contaminants in sediment because it has a high sorption capacity. In the present study, the sorption of pentachlorophenol (PCP) onto sediments supplemented with rice straw biochar (RC) and fly ash (FC) aged for different times and at temperatures were investigated. The sorption of PCP increased with increasing amounts of BC and decreased with aging time and storage temperature of the BC-supplemented sediments.