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ABSTRACT The discovery of denitrifying anaerobic methane oxidation (DAMO) processes enables the complete nitrogen removal from wastewater by utilizing the methane produced on site from anaerobic digesters. This model-based study investigated the mechanisms and operational window for efficient nitrogen removal by coupling nitritation-anaerobic ammonium oxidation (Anammox) and methane-dependent denitrification in membrane biofilm reactors (MBfRs). A mathematical model was applied to describe the microbial interactions among Anammox bacteria, DAMO archaea, and DAMO bacteria. The model sufficiently described the batch experimental data from an MBfR containing an Anammox-DAMO biofilm with different feeding nitrogen compositions, which confirmed the validity of the model. The effects of process parameters on the system performance and microbial community structure could therefore be reliably evaluated. The impacts of nitritation produced NO2−/NH4+ ratio, methane supply, biofilm thickness and total nitrogen (TN) surface loading were comprehensively investigated with the model. Results showed that the optimum NO2−/NH4+ ratio produced from nitritation for the Anammox-DAMO biofilm system was around 1.0 in order to achieve the maximum TN removal (over 99.0%), independent on TN surface loading. The corresponding optimal methane supply increased while the associated methane utilization efficiency decreased with the increase of TN surface loading. The cooperation between DAMO organisms and Anammox bacteria played the key role in the TN removal. Based on these results, the proof-of-concept feasibility of a single-stage MBfR coupling nitritation-Anammox-DAMO for complete nitrogen removal was also tested through integrating the model with ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) processes whilst controlling the dissolved oxygen (DO) concentration in the simulated system. The maximum TN removal was found to be achieved at the bulk DO concentration of around 0.17 g m−3 under the simulation conditions, with the AOB, Anammox bacteria and DAMO organisms coexisting in the biofilm. Biotechnol. Bioeng. 2016;113: 1035-1045. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Activated carbon fibers (ACFs) were firstly applied as fluidized solid carrier to immobilize photo-fermentative bacteria (PFB) for H2 production in batch culture. The observations by scanning electronic microscopy (SEM) demonstrated the close interaction between ACFs and PFB. The amount of immobilized bacteria and the performance of H2 production were strongly affected by specific surface area, length and amount of ACFs, respectively. Large specific surface area provided more surface attachment sites and more PFB were immobilized. ACFs with proper length avoided intertwining with each other and better fluidized during reactor operation. Excessive amount of ACFs not only limited the light conversion efficiency, but also increased biofilm detachment, resulting in low H2 yield. The maximum yield (3.08 mol H2 mol−1 acetate) and rate (32.85 ml l−1 h−1) of H2 production were obtained, using specific surface area (1500 m2 g−1), length (1 mm) and amount (0.8 g l−1) of ACFs. Compared with the conventional solid carriers, ACFs were effective solid carriers to immobilize PFB for improving H2 production, due to bacteria immobilized on the external surface of fluidized ACFs and formed a layer of dense biofilm. [Copyright &y& Elsevier]

The effect of different gases, CO2 concentration, and separation of CO2 from reaction system on photo-fermentation H2 production was investigated by batch culture in this study. Experimental results showed that different gases (Ar,N2,CO2, and air) as gas phase have obviously affected on photo-H2 production and a high concentration of CO2 can inhibit the growth and H2 evolution of Rhodopseudomonas faecalis RLD-53. When CO2 concentration at 5%, cell increased most rapidly the specific growth rate of 0.489g/l/h and the specific growth rate fell to be 0.265g/l/h when CO2 concentration at 40%. However, the growth of RLD-53 at CO2 concentration of 60–100% was almost completely inhibited. At CO2 concentrations of 5% and 10%, the maximum H2 yield was 2.54 and 2.59mol-H2/mol acetate, respectively, and it was similar with the control (2.61mol-H2/mol acetate). H2 not produced when CO2 concentration at 60–100%. In conclusion, separation of CO2 from reaction system can stimulate H2 production in the entire photo-H2 production process and H2 yield increased about 12.8–18.85% than the control. [Copyright &y& Elsevier]

Abstract: In the present study, the effect of Ni2+ (0–10μmol/l), Fe2+ (0–200μmol/l) and Mg2+ (0–15mmol/l) concentration on photo-hydrogen production from acetate was investigated by batch culture. Results showed that under a proper concentration range, Ni2+ was able to enhance the hydrogen production rate and the hydrogen yield; Fe2+ was able to increase the hydrogen yield, and hydrogen production rate was enhanced only when the culturing time was 24–72h. Ni2+ and Fe2+ at a higher concentration inhibited cell growth. When Ni2+ and Fe2+ concentrations were 4μmol/l and 80μmol/l, respectively, maximal hydrogen yield of 2.87 and 2.78mol H2/mol acetate was obtained when batch culturing at 35°C with initial pH 7.0. Mg2+ did not significantly affect hydrogen production and hydrogen yield which maintained at about 2.45mol H2/mol acetate, but it was favorable to cell growth. [Copyright &y& Elsevier]

This work developed a novel M embrane G ranular S ludge R eactor (MGSR) equipped with a gas permeable membrane module for efficient methane delivery to cultivate nitrate/nitrite dependent anaerobic methane oxidation (n-DAMO) microorganisms in granular sludge. As proof of concept, the MGSR was fed with synthetic wastewater containing nitrate and ammonium to facilitate the growth of n-DAMO microorganisms. The granular sludge of n-DAMO and Anammox was gradually developed and achieved a nitrogen removal rate of 1.08 g NO 3 - -N L -1 d -1 and 0.81 g NH 4 + -N L -1 d -1 . Finally, enriched granular sludge was successfully applied for nitrogen removal from the synthetic partial nitritation effluent. The combined dominance of n-DAMO archaea, Anammox bacteria, and n-DAMO bacteria in the microbial community was confirmed by 16S rRNA amplicon sequencing. Fluorescence in situ hybridization revealed that a layered structure was formed in the granular sludge with Anammox bacteria in the outer layer and n-DAMO microorganisms in the inner layer when granules were fed with nitrite and ammonium. The high performance of nitrogen removal (16.53 kg N m -3 d -1 ) with satisfactory effluent quality (∼8 mg N L -1 ) and excellent biomass retention capacity (43 g VSS L -1 ) make the MGSR promising for the practical application of n-DAMO and Anammox in wastewater treatment.

The fibroblast growth factor (FGF) system has been suggested to be involved in the development of schizophrenia (SCZ). However, the potential roles of all FGFs have not been well studied in the literature. Here, we investigated the concentration of peripheral blood fibroblast 10 (FGF10) in patients with SCZ to determine whether FGF10 could serve as a biomarker for SCZ. We recruited 130 SCZ patients (57 first-episode, drug-free patients and 73 chronically medicated patients) and 111 healthy controls. Our results showed that serum FGF10 levels were significantly decreased in SCZ patients when compared with controls. Sub-group analyses revealed that both first-episode, drug-free patients and chronically medicated patients had lower levels of FGF10 than controls. Moreover, both male and female SCZ patients had significantly decreased blood FGF10 levels relative to control subjects. Using a receiver operating characteristic curve, the optimal cutoff value of FGF10 level as an indicator for diagnosis of first-onset SCZ patients was projected to be 152.3 pg/ml, which yielded a sensitivity of 0.658 and specificity of 0.649, with an area under the curve of 0.665 (95% confidence interval, 0.577-0.754). Taken together, our results are the first to demonstrate an association between FGF10 and SCZ, providing further evidence for the neurotrophic factor hypothesis of SCZ.

To achieve energy neutral wastewater treatment, mainstream anaerobic ammonium oxidation (anammox) has attracted extensive attention in the past decade. However, the relatively high effluent nitrogen concentration (>10 mg N L -1 ) remains a significant barrier hindering its practical implementation. A novel technology integrating the anammox and denitrifying anaerobic methane oxidation (DAMO) reactions in a membrane biofilm reactor (MBfR) was developed in this study to enhance the mainstream anammox process. With the hydraulic retention time (HRT) progressively decreased from 12 to 4 h, the total nitrogen (TN) removal rate increased stepwise from 0.09 to 0.28 kg N m -3 d -1 , with an effluent TN concentration below 3.0 mg N L -1 achieved. Mass balance analysis showed that 30-60% of the nitrate produced by the anammox reaction was reduced back to nitrite by DAMO archaea, and the anammox and DAMO bacteria were jointly responsible for nitrite removal with contributions of >90% and <10%, respectively. Additionally, the established MBfR was robust and achieved consistently high effluent quality with >90% TN removal when the influent nitrite to ammonium molar ratio varied in the range of 1.17-1.55. Fluorescence in situ hybridization (FISH) and 16S rRNA gene sequencing indicated that anammox bacteria, DAMO bacteria and DAMO archaea jointly dominated the biofilm, and were likely the key contributors to nitrogen removal. This is the first study that a high nitrogen removal rate (>0.2 kg N m -3 d -1 ) and satisfactory effluent quality (∼3 mg TN L -1 ) were achieved simultaneously by integrating anammox and DAMO reactions in mainstream wastewater treatment., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Synergistic system of dark fermentation and algal culture was initially operated at batch mode to investigate the energy production and nutrients removal from molasses wastewater in butyrate-type, ethanol-type and propionate-type fermentations. Butyrate-type fermentation was the most appropriate fermentation type for the synergistic system and exhibited the accumulative hydrogen volume of 658.3 mL L -1 and hydrogen yield of 131.7 mL g -1 COD. By-products from dark fermentation (mainly acetate and butyrate) were further used to cultivate oleaginous microalgae. The maximum algal biomass and lipid content reached 1.01 g L -1 and 38.5%, respectively. In continuous operation, the synergistic system was stable and efficient, and energy production increased from 8.77 kJ L -1  d -1 (dark fermentation) to 17.3 kJ L -1  d -1 (synergistic system). Total COD, TN and TP removal efficiencies in the synergistic system reached 91.1%, 89.1% and 85.7%, respectively. This study shows the potential of the synergistic system in energy recovery and wastewater treatment., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Partial nitritation and Anammox processes are increasingly used for nitrogen removal from anaerobic sludge digestion liquor. However, their nitrogen removal efficiency is often limited due to the production of nitrate by the Anammox reaction and the sensitivity to the nitrite to ammonium ratio. This work develops and demonstrates an innovative process that achieves complete nitrogen removal from partially nitrified anaerobic sludge digestion liquor through the use of a membrane biofilm reactor (MBfR), with methane supplied through hollow fiber membranes. When steady state with a hydraulic retention time (HRT) of 1 day was reached, the process achieved complete nitrite and ammonium removal at rates of 560 mg N/L/d and 470 mg N/L/d, respectively, without any nitrate accumulation. The process is relatively insensitive to the nitrite to ammonium ratio, achieving complete nitrogen removal when their ratio in influent varied in the range of 1.125-1.32. Pyrosequencing and fluorescence in situ hybridization analysis revealed that denitrifying anaerobic methane oxidation (DAMO) archaea, Anammox bacteria and DAMO bacteria jointly dominated the microbial community. Mass balance analysis showed that nitrate produced by Anammox (122.2 mg N/L/d) was entirely converted to nitrite by DAMO archaea, while nitrite in the feed and produced by DAMO archaea was jointly removed by Anammox (90%) and DAMO bacteria (10%). The nitrogen removal rate of over 1 kg N/m 3 /d is comparable to the practical rates reported for side-stream nitrogen removal processes.