Sustainable wastewater treatment and reuse in space.

Exploring the vast extraterrestrial space is an inevitable trend with continuous human development. Water treatment and reuse are crucial in the limited and closed space that is available in spaceships or long-term use space bases that will be established in the foreseeable future. Dedicated water treatment technologies have experienced iterative development for more than 60 years since the first manned spaceflight was successfully launched.

Instant water toxicity detection based on magnetically-constructed electrochemically active biofilm.

Water toxicity determination with electrochemically active bacteria (EAB) is promising in the early warning of water pollution. However, limited by tedious biofilm formation, natural EAB biofilms are uncapable of the instant detection of water toxicity, resulting in the failure for the emergency monitoring of water pollution. To solve this problem, a novel method for the rapid construction of EAB biofilms using magnetic adsorption was established, and the performance of instant water toxicity detection with magnetically-constructed EAB biofilm was investigated.

Mechanism and applications of bidirectional extracellular electron transfer of .

Electrochemically active microorganisms (EAMs) play an important role in the fields of environment and energy. is the most common EAM. Research into contributes to a deeper comprehension of EAMs and expands practical applications.

On-site determination of water toxicity based on freeze-dried electrochemically active bacteria.

Our previous studies have reported water toxicity determination with a fresh electrochemically active bacteria (EAB) suspension as the sensing element, which exhibits high sensitivity and has great prospects in providing early warning about water pollution. However, because the preparation of fresh EAB suspensions is time-consuming, these studies are not suitable for the on-site determination of water toxicity. To solve this problem, this study investigated the rapid preparation of an EAB suspension by the rehydration of freeze-dried EABs and established a novel method for the on-site determination of water toxicity based on the freeze-dried EAB model strain Shewanella oneidensis MR-1.

Two polarity reversal modes lead to different nitrate reduction pathways in bioelectrochemical systems.

Polarity reversal is one of the effective strategies to rapidly start up denitrifying BESs，but the long-term performances of the denitrifying BESs operated under polarity reversal receive little attention. This study investigated the effects of periodic polarity reversal (PPR) and polarity reversal once only (PRO) on the long-term performances of denitrifying BESs. Repeatable oxidative and reductive currents were observed in the BESs obtained by PPR (PPR-BESs).

High-fat and high-protein diets from different sources induce different intestinal malodorous gases and inflammation.

Long-term unbalanced diet might lead to intestinal malodorous gas generation and inflammation, which would cause health problems, especially in confined environment. In this study, the effects of high-fat and high-protein diets from different nutrient sources, including casein lard, soy protein and soybean oil, and pork protein and lard, respectively, on the differences of malodorous gas compounds emission and inflammation in rats were explored as well as the correlation with gut microbiota. The results showed that all the high-fat and high-protein diets could induce organ damage, abnormal serum biochemical indexes and inflammation.

Enhancing the sensitivity of water toxicity detection based on suspended Shewanella oneidensis MR-1 by reversing extracellular electron transfer direction.

Water toxicity detection is of great significance to ensure the safety of water supply. With suspended electrochemically active bacteria (EAB) as the sensing element, a novel microbial electrochemical sensor (MES) has recently been reported for the real-time detection of water toxicity, but its practical applications need to further improve the sensitivity. Extracellular electron transfer (EET) is an important factor affecting MES performance.

Water recycle system in an artificial closed ecosystem - Lunar Palace 1: Treatment performance and microbial evolution.

Water recycle systems have important implications to realize material circulation in biological regeneration life support systems, which is of significance for long-term space missions and future planetary base. Based on membrane biological activated carbon reactor (MBAR) technologies, the 'Lunar Palace 365' experiment established various treatment processes for condensate wastewater, domestic wastewater, urine, and used nutrient solutions. The 370-day operation data showed the COD index of purified condensate wastewater decreased to 0.

Effect of solid waste fermentation substrate on wheat (Triticum aestivum L.) growth in closed artificial ecosystem.

Bioregenerative Life Support System (BLSS) is a closed artificial ecosystem and could provide oxygen, food, water and other substrates for long-term deep space survival. The treatment and recycle of the solid waste are crucial and rate-limiting steps in BLSS, and it's reported that the solid waste such as the inedible plants and human feces could be fermented aerobically and then reused as fertilizer for growing plants in BLSS, which may be an effective way to improve the solid waste recycling rate. However, the recycling performance and the effect on the system need to be evaluated.

Semi-continuous fermentation of solid waste in closed artificial ecosystem: Microbial diversity, function genes evaluation.

Bioregenerative Life Support System (BLSS) is a closed artificial ecosystem and could provide oxygen, food, water and other substances for space survival. Solid waste treatment is a key rate-limiting step in BLSS. In this study, solid wastes including wheat straw, human and yellow mealworm feces were disposed in a semi-continuous bio-convertor for 105 days in a ground-based experimental BLSS platform (Lunar Palace 1).

Dual detection of biochemical oxygen demand and nitrate in water based on bidirectional Shewanella loihica electron transfer.

This study for the first time proposed a method for simultaneously measuring BOD and nitrate in water using electrochemically active bacteria. Firstly, the bidirectional extracellular electron transfer (EET) capability of a model electricigen Shewanella loihica PV-4 was revealed. Then, based on the respective outward and inward EET, S.

The effect of anode hydrodynamics on the sensitivity of microbial fuel cell based biosensors and the biological mechanism.

Fluid dynamics in the anodic chamber of a microbial fuel cell (MFC) is a key factor affecting the distribution of substrates and the efficiency of mass transport. However, the effect of hydrodynamics on MFC based biosensor (MFC-Biosensor) sensitivity has not been established. In this study, the three-dimension anode flow field of a two chamber MFC was visualized, and anodic configuration optimized by a reasonable serpentine flow field and inlet/outlet settings.

Effect of control mode on the sensitivity of a microbial fuel cell biosensor with Shewanella loihica PV-4 and the underlying bioelectrochemical mechanism.

A relatively poor sensitivity is a critical challenge for the application of microbial fuel cell biosensors (MFC-biosensors). This study investigated the effects of two control modes on sensor sensitivity and revealed the underlying bioelectrochemical mechanism. The results demonstrated that the sensitivity of an S.

Sequential flowing membrane-less microbial fuel cell using bioanode and biocathode as sensing elements for toxicity monitoring.

Traditional microbial fuel cell based biosensor (MFC-Biosensor) utilizes bioanode as sensing element and delivers high sensitivity for single toxic shock but it fails to alert the combined shock of organic matter (OM)/toxic agent (TA). To address this limitation, this study developed a sequential flowing membrane-less MFC based biosensor (SMFC-Biosensor) using both bioanode and biocathode for toxicity monitoring. Results demonstrated the shocks of 1.

Effect of external resistance on the sensitivity of microbial fuel cell biosensor for detection of different types of pollutants.

The relatively poor sensitivity is the main bottleneck restricting the application of microbial fuel cell biosensor (MFC-biosensor) for toxicity monitoring. Previous studies have shown that external resistance (R) had an obvious effect on sensor sensitivity. However, these studies reported different results and the reason of this discrepancy was not clear.

Comparative analysis of microbial fuel cell based biosensors developed with a mixed culture and Shewanella loihica PV-4 and underlying biological mechanism.

Microbial fuel cell based biosensors (MFC-biosensors) utilize anode biofilms as biological recognition elements to monitor biochemical oxygen demand (BOD) and biotoxicity. However, the relatively poor sensitivity constrains the application of MFC-biosensors. To address this limitation, this study provided a systematic comparison of sensitivity between the MFC-biosensors constructed with two inocula.

Urea removal coupled with enhanced electricity generation in single-chambered microbial fuel cells.

High concentration of total ammonia nitrogen (TAN) in the form of urea is known to inhibit the performance of many biological wastewater treatment processes. Microbial fuel cells (MFCs) have great potential for TAN removal due to its unique oxic/anoxic environment. In this study, we demonstrated that increased urea (TAN) concentration up to 3940 mg/L did not inhibit power output of single-chambered MFCs, but enhanced power generation by 67% and improved coulombic efficiency by 78% compared to those obtained at 80 mg/L of TAN.

Brush-like polyaniline nanoarray modified anode for improvement of power output in microbial fuel cell.

Carbon cloth with brush-like polyaniline (BL-PANI) nanowire arrays generated on the surface was utilized as anode material in this study to improve the power output of MFCs. A novel pulsed voltage method was applied to fabricate BL-PANI with PANI nanowires of ∼230nm of length. By using BL-PANI modified carbon cloth as anode, the power output was improved by 58.

Element Cycling and Energy Flux Responses in Ecosystem Simulations Conducted at the Chinese Lunar Palace-1.

Bioregenerative life-support systems (BLSS) address interactions between organisms and their environment as an integrated system through the study of factors that regulate the pools and fluxes of materials and energy through ecological systems. As a simple model, using BLSS is very important in the investigation of element cycling and energy flux for sustainable development on Earth. A 105-day experiment with a high degree of closure was carried out in this system from February to May, 2014, with three volunteers.

How to Establish a Bioregenerative Life Support System for Long-Term Crewed Missions to the Moon or Mars.

To conduct crewed simulation experiments of bioregenerative life support systems on the ground is a critical step for human life support in deep-space exploration. An artificial closed ecosystem named Lunar Palace 1 was built through integrating efficient higher plant cultivation, animal protein production, urine nitrogen recycling, and bioconversion of solid waste. Subsequently, a 105-day, multicrew, closed integrative bioregenerative life support systems experiment in Lunar Palace 1 was carried out from February through May 2014.

Microbiological mechanism of the improved nitrogen and phosphorus removal by embedding microbial fuel cell in Anaerobic-Anoxic-Oxic wastewater treatment process.

Anaerobic-Anoxic-Oxic (AA/O) wastewater treatment process is a widely used wastewater treatment process for simultaneous nitrogen and phosphorus removal. Microbial fuel cell (MFC) can generate electricity and treat the organic wastewater simultaneously. Our previous research showed that embedding MFC in AA/O wastewater treatment process could enhance the pollutants removal efficiency.

Rearing Tenebrio molitor L. (Coleptera: Tenebrionidae) in the "Lunar Palace 1" during a 105-day multi-crew closed integrative BLSS experiment.

Yellow mealworm (Tenebrio molitor L.) is one of the animal candidates for space bioregenerative life support systems. In this study, T.

Facilitated extracellular electron transfer of Shewanella loihica PV-4 by antimony-doped tin oxide nanoparticles as active microelectrodes.

Dissimilatory metal reducing bacteria are capable of extracellular electron transfer (EET) to insoluble metal oxides as external electron acceptors for their anaerobic respiration, which is recognized as an important energy-conversion process in natural and engineered environments, such as in mineral cycling, bioremediation, and microbial fuel/electrolysis cells. However, the low EET efficiency remains one of the major bottlenecks for its practical application. We report firstly that the microbial current generated by Shewanella loihica PV-4 (S.

Photosynthetic characteristics, antioxidant capacity and biomass yield of wheat exposed to intermittent light irradiation with millisecond-scale periods.

Energy consumption and output are two very important standards for evaluating the reliability of electric light sources when plants are grown in a controlled environment. As a primary source of energy, light is one of the most important environmental factors for wheat growth. The objective of this study was to investigate the influences of light/dark cycle operation with millisecond-scale period on the growth of wheat, photosynthetic characteristics, antioxidant capacity and biomass yield and quality during their life cycle.