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[Display omitted] • Increased paramylon productivity was achieved using hydrolysate-based medium. • Cell immobilisation was assessed for efficient paramylon production by E. gracilis. • Waste sponge was demonstrated to be promising for efficient paramylon production. • Productivity of 1.77 g/L/day was achieved using waste-based cell immobilisation. Microalga represents a promising platform for numerous valuable bioproducts, but the production cost and efficiency remain major challenges for the industrial implementation. In this study, the production of paramylon (polysaccharides) from microalga Euglena gracilis using food waste hydrolysate and cell immobilisation cultivation was assessed. Synthetic medium supplemented with food waste hydrolysate proved to be a feasible option and achieved the paramylon productivity of 1.46 g/L/day in the heterotrophic (HT) cultivation. In addition, waste-based supporting materials were investigated for cell immobilisation cultivation, and waste sponge demonstrating good cell viability and paramylon productivity with maximum of 2.22 g/L/day was achieved using the synthetic medium in HT condition. However, sugarcane bagasse was not suitable for E. gracilis immobilisation as it induced serious cell lysis and oxidative stress under heterotrophic cultivation. The subsequent utilisation of the hydrolysate-based medium coupled with waste-based cell immobilisation cultivation resulted in the paramylon productivity of 1.77 g/L/day, demonstrating a promising fermentation strategy for sustainable and efficient paramylon production. This study serves as a noteworthy example of producing microalgal metabolites from the food waste hydrolysate using waste-based cell immobilisation technique. Overall, our findings provide valuable insights into green and sustainable production of microalgal biorefineries, and contributes to the advancement of the circular bioeconomy. [ABSTRACT FROM AUTHOR]

• Basic principles and affecting parameters of electrospinning process are overviewed. • Summary of application of electrospinning biohybrid technology. • Applications of electrospinning biohybrid technology targeting different pollutants. • Microbial selection, fabricating routes of electrospinning biohybrid composites. • Bioremediation capacity of electrospinning biohybrid technology in water treatment. • The actual state and future challenges of electrospinning biohybrid technology. With the rapid development of nanotechnology and additive manufacturing industries, electrospinning for the fabrication of high-performance nanofibers has attracted increasing attention. The rapid development of biohybrid environmental remediation technology has led to sustainable water treatment materials aimed at different pollutants and application scenarios. The coupling of biohybrid materials with electrospinning technology further addresses potential drawbacks of traditional biomaterials, such as low activity, poor diffusion, and loss of biological activity. In recent years, advanced techniques for constructing biohybrid fibers have been achieved through electrospinning methods such as fiber encapsulation, microtube encapsulation, and co-electrospinning, utilizing microbial cells (bacteria, algae, yeast, etc.). In this review, we firstly introduce the basic principle of electrospinning technology and parameters affecting spinning process. Then systematically analyze the microbial selection, material synthesis routes, and degradation efficiency of electrospinning biohybrid technology in water treatment processes targeting different pollutants, while assessing the application prospects or drawbacks of each case. Finally, we summarize and prospect the technical characteristics, current issues, and industrial prospects of electrospinning biohybrid technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • The role played by NTP on the stabilization enhancement of Tl soils was explored. • NTP explicitly changed the physicochemical characteristics of common stabilizers. • Chemical speciation of Tl in soils influenced by NTP stabilizer was fully tracked. • NTP-PK-SDDCs were prepared and employed to diversify the stabilization pathways. • The study broadens the application of common stabilizers for HM-polluted soils. Thallium (Tl) is a highly toxic element and can accumulate in human body through food, water, or air and cause damage to multiple organs. In this study, the nonthermal plasma (NTP) was employed to irradiate the potassium dihydrogen phosphate (KH 2 PO 4) and sodium diethyldithiocarbamate trihydrate (SDDC) to solve the issues brought by their poor stability and insufficient chelation capabilities in soils to intensify their performance on immobilizing monovalent Tl contaminants in soils. Both an orthogonal design (OD) and a central composite design (CCD) were adopted to arrange the multi-parametrical modification and stabilization experiments. The leaching toxicities ranging from 5.11 to 52.37 µg/L of Tl+ ions were obtained in the OD experiments. The changes in both NTP time and the molar ratios of KH 2 PO 4 to SDDC had a significant effect on the activation procedure. The leaching concentration ranging from 0.37 to 7.34 µg/L was achieved in the CCD stabilization experiments. NTP activation and the rearrangement of the stabilization conditions both were beneficial to the transformation of physicochemical states of Tl pollutants in soils, which proved the existence of chemical immobilization brought by the irradiated stabilizers (NTP-PK-SDDCs) to the Tl contaminants. The stabilization process was targeted between only Tl contaminants and NTP-PK-SDDCs in soils. The NTP irradiation enhanced the physicochemical characteristics of stabilizers, further intensifying the immobilization of Tl species in the soils. The enhancement mechanism was attributed to the free radicals-induced doping, oxidation, and polycondensation and the bombards of electrons, which strengthened the electrostation and chemisorption of NTP-PK-SDDCs towards Tl ions. The potential impact of this study includes the development of more effective and sustainable remediation methods for Tl-contaminated soils, contributing to environmental protection and human health. [ABSTRACT FROM AUTHOR]

[Display omitted] • A core–shell QQ-encapsulated structure was prepared by a standardized method. • SIPN shell enables excellent biocontainment with physical and chemical stability. • The anti-biofouling and phosphorus removal were enhanced in QQ microcapsule MBR. • QQ microcapsule promoted the application of QQ media for anti-biofouling in MBR. Microbial quorum quenching (QQ) has been proven to be a sustainable anti-biological fouling strategy for membrane bioreactors (MBR), but the long-term stability and practical application in MBR were uncertain. We reported a novel semi-interpenetrating network (SIPN) hydrogels-based design of QQ bacteria (Rhodococcus sp. BH4) encapsulation for both biofouling control and enhancement of organic pollutants removal in MBR. The microcapsule included the alginate core, chitosan thin intermediate compartment and SIPN (sodium alginate / polyacrylamide) shell, which exhibited near-perfect biocontainment, including preventing detectable QQ bacteria escape and improving mechanical strength. The QQ-microcapsules in the MBR demonstrated its significant anti-biofouling effect for treating synthetic wastewater (i.e., membrane fouling was delayed by 233%-280% compared to the control MBR membrane). Meanwhile, the efficiency of phosphorus removal was developed in QQ-microcapsule MBR because of the enhanced phosphorus removal triggered by the flocculation of polyacrylamide (PAM) fraction in SIPN. This promising QQ media brings the broad potential for biofouling control and long-term efficient operation in actual MBR wastewater treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • This is the first report of an ultrafiltration (UF) membrane microreactor (MMR). • The UF MMR is made by blending Zr hydroxide and quaternary ammonium with PVDF. • The MMR has pore size and water flux typical of conventional UF membranes. • With high flux, the MMR can simultaneously remove nitrate and phosphate from water. • The MMR has high nitrate/phosphate adsorption ability and regeneration capacity. Abstract Removing low-concentration nitrate and phosphate from water is desirable because they may cause eutrophication when discharged, but it is challenging using current technologies. Although ultrafiltration (UF) membranes have higher permeability than nanofiltration and reverse osmosis membranes, they cannot remove nitrate and phosphate from water because of their low selectivity. It is the first time for a work to develop a novel UF membrane microreactor (MMR) simultaneously removing nitrate and phosphate with high capacity and selectivity. The UF MMR was fabricated by blending amorphous zirconium hydroxide and quaternary ammonium powder with poly(vinylidene fluoride) and had structure and pore size typical of conventional UF membranes. The MMR adsorption capacities for nitrate and phosphate were 9.66 mg-N/g and 15.58 mg-P/g, respectively. Adsorption followed pseudo second order rate law and was dominated by chemical adsorption. Coexisting sulfate ions usually compete strongly with nitrate and phosphate, but had little influence on removal using the UF MMR. The UF MMR had high permeability (500 LMH/MPa) and maintained excellent removal of nitrate and phosphate after regeneration with NaCl solution, making it a promising technology for water and wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effects of origins and storage conditions on four types of food waste were analysed. • Designed storage conditions had no significant effect on the studied food wastes. • Food waste hydrolysates were valorised via fermentation by Euglena gracilis. • Potential inhibitors were identified using untargeted metabolite analysis. Food wastes used as feedstock in biorefineries are of both research and market interest for solving related environmental issues and valorising to value-added products. However, the distinct conditions and characteristics governing the valorisation of different types of food waste remain to be addressed, such as different origins and storage conditions of food wastes. In this study, the characteristics of four types of food waste (student canteen waste, bakery waste, Chinese food waste, and Western food waste) after designed storage experiments (storage temperature − 4°C, 25 °C, and 35 °C; storage duration 1–3 days) were first investigated, followed by enzymatic hydrolysis to obtain food waste hydrolysates that can be applied to microalgal fermentation. The results showed that the characteristics of the food wastes and their corresponding hydrolysates differed based on their origins. Furthermore, cultivation of the microalgae Euglena gracilis demonstrated the feasibility of using food waste hydrolysates as the sole nutrient source, and both the origin and storage conditions of food wastes were found to affect microalgal growth and paramylon production. Possible inhibitors that could account for the different performances of food waste hydrolysates were identified by untargeted metabolite analysis. In summary, this study provides insights into the application of different types of food waste under complex conditions in biorefineries and the utilisation of their hydrolysates via in-depth metabolite analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The chromogenic paper chip was facilely prepared by one-pot synthesis. • The "all-in-one" strategy fundamentally improves the stability and convenience. • Glucose level can be noninvasively detected with "sample in, result out" manner. • A smartphone App was developed for further improving the accuracy and ease of use. Noninvasive glucose detection for diabetes monitoring, in comparison with the conventional finger-prick test that causes inevitable pain, is on demand. Salivary glucose level that possesses a well-established correlation with blood glucose level can be a promising alternative for noninvasive detection, however, the sensitivity and user-friendliness remained to be improved. Herein, an "all-in-one" paper chip was fabricated by one-pot method for sensitive and user-friendly detection of salivary glucose level. Glucose oxidase (GOx) and the chromogenic reagent, luminol, were both in situ encapsulated in a metal–organic framework, ZIF-67, to form the GOx&luminol@ZIF-67@Paper (G&L@ZIF@Paper). Owing to the specificity of GOx and the peroxidase activity of ZIF-67, the paper chips are highly sensitive and specific for glucose with a linear range from 0.2 to 2 mM, and a limit of detection of 0.12 mM (S/N = 3). Moreover, ascribing to the protection and "all-in-one" structure by ZIF-67, the chip is highly stable that maintains the detection performance after storage at room temperature in air for 4 weeks, and this strategy also facilitates the one-pot detection without multiple steps of sampling and incubation. With the assistance of a smartphone application, the glucose level in saliva can be accurately detected with "sample-in-result-out" manner, and the results were highly consistent with those measured by commercial kit. This paper chip is a promising device for daily glucose monitoring, and the highly-integrated strategy provides an innovative resolution for the construction of colorimetric paper chips. [ABSTRACT FROM AUTHOR]

[Display omitted] • Introduing N defects over g-C 3 N 4 significantly increased photocatalytic activity. • An IEF was built to further strengthened the transport of photoexcited carriers. • The excellent O 2 adsorption capacity promoted H 2 O 2 production via 2e− ORR. • A possible H 2 O 2 generation pathway formed via 1O 2 was proposed. The development of photocatalysts for the efficient generation of hydrogen peroxide (H 2 O 2) and degradation of antibiotic pollutants is a mutual-beneficial solution to the chemical resource demands and environmental remediation. Herein, efficient visible-light-driven H 2 O 2 production and antibiotic degradation are achieved by using nitrogen-deficient modified polymeric carbon nitride (g-C 3 N 4) to facilitate the reduction of dioxygen. The N defects modified g-C 3 N 4 reached an excellent H 2 O 2 generation rate of 623.5 μmol g−1h−1 without O 2 bubbling. The structural features and entire photocatalytic conversion process were systematically studied via experiments and theoretical calculations. It was found that the N defects in the framework constructed a giant internal electric field (IEF), which effectively inhibited carrier recombination. Revealed the neglected H 2 O 2 production via 1O 2 pathway, which effectively promoting the selective 2e− oxygen reduction reaction (ORR). More interestingly, the N defects structure greatly improved the O 2 adsorption ability and O 2 production ability of the material, while inhibiting the in situ generated H 2 O 2 from being decomposed and maintaining high efficiency of H 2 O 2 production under air conditions. This study thoroughly revealed the synergistic effects of the terminal cyano group and nitrogen vacancies over g-C 3 N 4 for efficient H 2 O 2 photogeneration photosynthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The BH4 immobilized media were prepared using nano-silica and silica beads as core reinforcements. • The inclusion of two types of silicon in the beads ensured they were ready for prolonged use. • The application of two quorum quenching media effectively mitigated MBR biofouling. Quorum quenching (QQ) is a strategy to alleviate membrane biofouling in membrane bioreactors (MBRs). As a stable inorganic material with a large specific surface area, silica is often used to prepare of microbial immobilization composites. This study selected two different sizes of silica materials (silica beads and Nano-silica) to make the core encapsulate a QQ bacterial strain (Rhodococcus sp. BH4). The compressive strength and stability under extreme environments were characterized, and the positive effect of silica on QQ beads was verified. The results showed that both QQ beads could resist the impact of high pressure, acid, alkali, salt and EDTA buffer. It was proved that they have the potential to quench effectively continuously. Both beads were still more than 70 % QQ activity after five months of use. In the lab-scale continuous MBR experiment, the time of transmembrane pressure (TMP) reaching 50 kPa in both experimental groups was more than 3 times that in the blank group. The TMP contamination time was extended from 5 to 6 days in the blank group to 18–19 days. Among them, silica beads greatly improve the compressive strength of the beads, and also have a better performance in QQ. [ABSTRACT FROM AUTHOR]

[Display omitted] • An Eu3+-based sensor has been explored for specific recognizing ST and 5-HI-3-AA. • The detection limit for ST and 5-HI-3-AA is 0.013 and 0.15 µM, respectively. • The sensor can be recycled and reused to monitor ST and 5-HI-3-AA. • The sensor specifically recognizes ST among monoamine neurotransmitters. • This work provides a portable method for visual detection of biomarkers. Monoamine neurotransmitters such as L-epinephrine (EPI), norepinephrine (NE), dopamine (DA), and serotonin (ST) are important biomarkers for neurological diseases. However, specific detection of a single monoamine neurotransmitter is challenging. In this work, a water-stable fluorescent biosensor, Eu3+-doped UiO-66 metal–organic framework (EuUPDC), is constructed for specific recognition of ST and its metabolite, 5-hydroxyindole-3-acetic acid (5-HI-3-AA). The detection limits of EuUPDC for ST and 5-HI-3-AA are 0.013 μM and 0.15 μM, respectively. The LOD value for ST is 10-fold improvement compared to the reported fluorescent sensors. Importantly, the biosensor specifically recognizes ST at very low concentrations in the presence of co-existing monoamine neurotransmitters. Furthermore, the EuUPDC biosensor is successfully applied for the determination of ST and 5-HI-3-AA in human serum and urine with good recoveries. Finally, a EuUPDC -embedded test strip is fabricated and portable smartphone-assisted RGB color values are effectively integrated with a lowest detectable value of 0.6 μM for ST and 6.7 μM for 5-HI-3-AA. The designed biosensor EuUPDC has great potential for the quantitative determination of ST and 5-HI-3-AA, and applicable for early diagnosis of neurological diseases. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel composites named TIGCAB were successfully prepared. [•] TIGCAB are excellent photocatalysts for the reduction of Cr(VI). [•] TIGCAB can be separated from reaction medium easily. [•] Fe(III) ions can inhibit electron–hole recombination and promote the photoreduction of Cr(VI). [•] TIGCAB can be reused for at least three cycles in batch experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel magnetic hybrid coagulant (MHC) was synthesized. • MHC settling time was 2/3 shorter than traditional magnetic seeding coagulation. • MHC efficiently removed dissolved contaminants such as NO 3 −-N and organic nitrogen. • The NO 3 −-N removal pathways by MHC were clarified by MD simulations. • MHC was regenerated by Donnan dialysis combined with biodegradation. Dissolved contaminants (nitrate nitrogen, etc.) in municipal sewage effluent and polluted water resources need to be further removed, but common advanced water treatment technologies usually have unsatisfactory performance and large process footprints. Magnetic seeding coagulation (MSC) has a rapid settling speed; however, it is less effective for removing dissolved contaminants and cannot recover effective components. Herein, a novel covalently bound magnetic hybrid coagulant (MHC) was synthesized and used to treat secondary biological effluent. MHC settling time was 2/3 shorter than traditional MSC and showed high removal efficiencies for conventional coagulation indicators and dissolved contaminants such as nitrate nitrogen and organic nitrogen. The nitrate nitrogen removal mechanisms included nitrate nitrogen capture through the electrostatic attraction and the collision efficiency enhancement. MHC integral structure can be bioregenerated for multiple cycles. Because of its effectiveness in removing dissolved contaminants rapidly, MHC has potential application in advanced water treatment, especially in land-scarce areas. [ABSTRACT FROM AUTHOR]