Simultaneous nitrogen removal via heterotrophic nitrification and aerobic denitrification by a novel Lysinibacillus fusiformis B301.

Simultaneous nitrogen removal via heterotrophic nitrification and aerobic denitrification (HN-AD) has received widespread attention in biological treatment of wastewater. This study reported a novel Lysinibacillus fusiformis B301 strain, which effectively removed nitrogenous pollutants via HN-AD in one aerobic reactor with no nitrite accumulated. It exhibited the optimal nitrogen removal efficiency under 30°C, citrate as the carbon source and C/N ratio of 15.

Phosphorus removal from wastewater using Ca-modified attapulgite: Fixed-bed column performance and breakthrough curves analysis.

The adsorbent calcium-modified attapulgite (Ca-GAT) prepared by calcium chloride modification and high temperature treatment (700 °C) has proved to remove phosphorus in low-concentration phosphorus wastewater in batch adsorption experiments. Dynamic adsorption performance and industrial application potential still need further determination. This study explored the effects of various parameters on the dynamic phosphorus adsorption, including initial phosphate concentration (2-10 mg/L), flow rate (1-3 mL/min) and adsorption bed height (2-6 cm).

Calcium-modified granular attapulgite removed phosphorus from synthetic wastewater containing low-strength phosphorus.

Traditional biological processes combined with chemical precipitation methods can effectively reduce phosphate concentration in wastewater. However, discharge standards required additional advanced treatment technologies, and the removal of low phosphorus concentration is complicated and expensive. This study proposes application of a simple and recyclable adsorbent to remove low-concentration phosphorus from water.

Effect of addition sites on bioaugmentation of tea polyphenols-NZVI/PE composite packing: Nitrogen removal efficiency and service life.

Although efficient improvement of the nitrogen removal from wastewater by adding iron was achieved in wastewater process, the influence mechanism of addition sites is unclear. The study was based on the A/O-MBR treating simulated domestic wastewater, and tea polyphenol-nano zero-valent iron/polyethylene packing (TP-NZVI/PE) was added into the anoxic tank, aerobic tank and membrane effluent end of the process, respectively. The effect of the different addition sites on the nitrogen removal performance of A/O-MBR was investigated.

Green synthesis of modified polyethylene packing supported tea polyphenols-NZVI for nitrate removal from wastewater: Characterization and mechanisms.

Nano-zero-valent iron (NZVI), as an electron donor, performed excellence in the reduction and remove of nitrate. However, the easy agglomeration and poor antioxidation of NZVI declined the nitrate removal and limited the application in the field of wastewater treatment. Herein, a novel composite packing of tea polyphenol, NZVI and modified polyethylene carrier (TP-NZVI/PE) was prepared and characterized, the removal efficiency of nitrate was verified, and the preliminary removal mechanism was finally investigated.

Pathway analysis of the biodegradation of lignin by Brevibacillus thermoruber.

With increased interest in the biodegradation of lignin, there is a pressing need to evaluate the feasibility of using microorganisms for lignin degradation. A novel Bacillus strain was separated from compost and identified as Brevibacillus thermoruber. B.

Exogenous Ca enhances antioxidant defense in rice to simulated acid rain by regulating ascorbate peroxidase and glutathione reductase.

Exogenous calcium enhances rice tolerance to acid rain stress by regulating isozymes composition and transcriptional expression of ascorbate peroxidase and glutathione reductase. Calcium (Ca) participates in signal transduction in plants under abiotic stress, and addition of Ca is beneficial to alleviate damage of plants caused by acid rain. To clarify the effect of exogenous Ca on tolerance of plants to acid rain stress, we investigated regulation of Ca (5 mM) on activities, isozymes composition and transcriptional expression of ascorbate peroxidase (APX) and glutathione reductase (GR), redox state, and HO concentration and growth in rice leaves and roots under simulated acid rain (SAR) stress.

Calcium regulates antioxidative isozyme activity for enhancing rice adaption to acid rain stress.

Acid rain, as a typical abiotic stress, damages plant growth and production. Calcium (Ca) mediates plant growth and links the signal transduction in plants for adapting to abiotic stresses. To understand the effect of Ca on plant adaptable response to acid rain, we investigated changes in activities and gene expression of antioxidative enzymes and fatty acid composition of membrane lipid in rice seedlings treated with exogenous Ca (5 mM) or/and simulated acid rain (SAR, pH 3.

Synthesis of Fe/FeO@porous carbon through a facile heat treatment of iron-containing candle soots for peroxymonosulfate activation and efficient degradation of sulfamethoxazole.

Developing highly efficient, reusable, non-toxic and low-cost catalysts is of great importance for persulfate-based advanced oxidation processes (AOPs). In this work, ferrocene was mixed into paraffin to prepare a candle, and the iron-containing candle soots were collected and heated at 500 °C~900 °C under N atmosphere for 1 h to prepare magnetically recyclable Fe/FeO@porous carbon (Fe/FeO@PC) catalysts. The Fe/FeO@PC-700 obtained after pyrolysis at 700 °C exhibited the best catalytic activity for sulfamethoxazole (SMX) degradation.

Effect of microcystins at different rice growth stages on its yield, quality, and safety.

Microcystins (MCs) in water for irrigation may damage crop growth and enter food chains to threaten human health. To evaluate the potential risk of irrigation water contaminated with MCs, we exposed rice at each of the seedling, booting, and filling stages to irrigation water spiked with MCs at 1, 10, 100, and 1000 μg/L for 7 days. Afterwards, all rice underwent a recovery (without MCs) till the harvest.

Self-generated electric field to suppress sludge production and fouling development in a membrane bioreactor for wastewater treatment.

Compared with conventional sludge reduction techniques, electric field assisted membrane bioreactor (MBR) is a cost-effective technology with low power consumption. In this study, spontaneous electric field without extra power supply was introduced into the MBR for wastewater treatment to complete the in situ sludge reduction and membrane fouling mitigation. A novel spontaneous electric field membrane bioreactor (SEF-MBR) equipped with Cu-nanowires (Cu-NWs) conductive microfiltration membrane as cathode was established by using baffles to form anaerobic and aerobic tanks.

Thermally treated candle soot as a novel catalyst for hydrogen peroxide in-situ production enhancement in the bio-electro-Fenton system.

Thermally treated candle soot (TCS) was used as a two-electron (2e¯) oxygen reduction reaction (ORR) catalyst to in situ produce HO in a bio-electro-Fenton (BEF) system. Compared with the pristine candle soot (CS), TCS showed larger Brunauer-Emmett-Teller (BET) surface area (102.54 m g vs.

A triple-chamber microbial fuel cell enabled to synchronously recover iron and sulfur elements from sulfide tailings.

Bioleaching by coupling iron oxidization with microbial growth is a process frequently used to extract target metals from sulfide tailing piles. However, the slower leaching, longer operational times, and lower efficiency compared to those of other extracting processes are the most important reasons that make this approach unattractive for the recovery of target elements. A triple-chamber microbial fuel cell (MFC) was explored to elevate the dissolution of sulfide tailings via in-situ removal of bioleached Fe/Fe and SO, during which iron and SO ions were synchronously recovered as Fe(OH) and S° in the first and second cathode chambers, respectively.

Effect of heterotrophic anodic denitrification on anolyte pH control and bioelectricity generation enhancement of bufferless microbial fuel cells.

Heterotrophic anodic denitrification (HAD) in the single-chamber microbial fuel cell (MFC) is a promising nitrogen removal technology. In this paper, the benefit (anolyte pH increase) and challenge (substrate consumption) brought by the heterotrophic anodic denitrification process for the electricity generation of bufferless MFCs were studied for the first time. Substrate anaerobic hydrolysis dramatically decreased the anolyte pH to 5.

Response of hormone in rice seedlings to irrigation contaminated with cyanobacterial extract containing microcystins.

Microcystins released by cyanobacteria affect crop growth and productivity, and even food safety. Plant hormones play a vital role in regulating growth, development and stress response in plants. Therefore, we studied the response of hormones including abscisic acid (ABA), indole-3-acetic acid (IAA), Zeatin (ZT) and gibberellin (GA) as well as hormone balances (IAA/ABA, ZT/ABA and GA/ABA) to cyanobacterial extract containing microcystins (1, 10, 100 and 1000 μg/L) during stress and recovery periods.

Responses of antioxidative enzymes and gene expression in Oryza sativa L and Cucumis sativus L seedlings to microcystins stress.

Microcystins (MCs) have become an important global environmental issue, causing oxidative stress, which is an important toxic mechanism for MCs in plants. However, the regulating mechanism of antioxidative enzymes in plants in adapting to MCs stress remains unclear. We studied the dynamic effects of MCs at different concentrations (5, 10, 50 and 100 μg/L) in rice and cucumber seedlings on relative growth rate (RGR), and reactive oxygen species and malondialdehyde (MDA) content, and antioxidative enzyme activities, during a stress period (MCs exposed for 1, 3, 5 and 7 d) and recovery period (7 d).

The growth process of the cake layer and membrane fouling alleviation mechanism in a MBR assisted with the self-generated electric field.

The electric field assisted membrane bioreactor (MBR) is an effective technique to alleviate membrane fouling. In this study, the spontaneous electric field was introduced into the MBR to observe the growth process of cake layer on the membrane surface. The external resistance for spontaneous electric field MBR (S-50) and S-500 were 50 Ω and 500 Ω respectively.

Comparison of plasma membrane H-ATPase response to acid rain stress between rice and soybean.

Acid rain is a global environmental issue due to inhibiting severely plant growth and productivity. To discover the tolerant mechanism in plants under acid rain stress, we studied the difference in response of two crops (rice and soybean) to simulated acid rain (pH 5.0 ~ 2.

Effect of anaerobic sludge on the bioelectricity generation enhancement of bufferless single-chamber microbial fuel cells.

Enhancing the self-buffering capacity is critical in the operation of bufferless microbial fuel cells (BLMFCs). Inorganic carbon (IC) is an ideal endogenous buffer, but its spontaneously accumulated concentration is insufficient to adjust anolyte pH. In this study, BLMFCs were operated with anaerobic sludge to enhance IC accumulation and increase anolyte pH.

Endogenous inorganic carbon buffers accumulation and self-buffering capacity enhancement of air-cathode microbial fuel cells through anolyte recycling.

Anolyte acidification is inevitable in the operation of buffer-free microbial fuel cells (MFCs), which restricts the proliferation and metabolism of electroactive bacteria, and results in electric-power deterioration. The anodic metabolic end-products, inorganic carbons (IC), which are composed of HCO (dissolved CO), HCO, and CO, are ideal endogenous buffers, whereas the naturally accumulated IC are far from enough to prevent anolyte acidification. In this work, different volume ratios of the anolytes (10%, 30%, and 50%) were recycled to increase the IC concentrations of the single-chamber air-cathode buffer-free MFCs.

A spontaneous electric field membrane bioreactor with the innovative Cu-nanowires conductive microfiltration membrane for membrane fouling mitigation and pollutant removal.

In this study, a spontaneous electric field membrane bioreactor (SEF-MBR), equipped with the innovative Cu-nanowires conductive microfiltration membrane, was developed to achieve membrane fouling mitigation and high-quality effluent. The membrane fouling was significantly mitigated due to the presence of spontaneous electric field that the intensity of the spontaneous electric field in the established SEF-MBR was up to 0.073 V/cm.

Exogenous application of Ca mitigates simulated acid rain stress on soybean productivity and quality by maintaining nutrient absorption.

Acid rain is a global environmental problem that threatens agricultural production. Calcium (Ca), as a signal substance for physiological activities, has been known to regulate plant growth under abiotic stresses. To clarify whether calcium could be one of possible ways to alleviate the reduction caused by acid rain in agricultural production and investigate its regulating mechanism on adaptation of plants under acid rain stress, we studied the effect of exogenous Ca (5 mM CaCl) on growth of soybean at different growth stages (seedling, flowering-podding, and filling stages) as well as yield and grain quality of soybean under simulated acid rain (pH 4.

Effect of exogenous calcium on growth, nutrients uptake and plasma membrane H-ATPase and Ca-ATPase activities in soybean (Glycine max) seedlings under simulated acid rain stress.

Calcium (Ca) is one of essential elements for plant growth and development, and also plays a role in regulating plant cell physiology and cellular response to the environment. Here, we studied whether calcium played a role in enhancing tolerance of plants to acid rain stress by hydroponics and simulating acid rain stress. Our results show that acid rain (pH 4.

Effect of exogenous abscisic acid on morphology, growth and nutrient uptake of rice (Oryza sativa) roots under simulated acid rain stress.

Application of proper ABA can improve acid tolerance of rice roots by balancing endogenous hormones and promoting nutrient uptake. Abscisic acid (ABA) has an important signaling role in enhancing plant tolerance to environmental stress. To alleviate the inhibition on plant growth and productivity caused by acid rain, it is crucial to clarify the regulating mechanism of ABA on adaptation of plants to acid rain.

Enhanced bioelectricity generation of air-cathode buffer-free microbial fuel cells through short-term anolyte pH adjustment.

Short-term initial anolyte pH adjustment can relieve the performance deterioration of the single-chamber air-cathode buffer-free microbial fuel cell (BFMFC) caused by anolyte acidification. Adjusting the initial anolyte pH to 9 in 5 running cycles is the optimum strategy. The relative abundance of the electrochemically active Geobacter in the KCl-pH9-MFC anode biofilm increased from 59.