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[Display omitted] • PAN/TiO 2 @PDA@BiOBr (PTPB-8) electrospun membrane is fabricated. • PTPB-8 has water contact angle of ∼ 0°/underwater oil contact angle of 154.7 ± 2.5°. • PTPB-8 exhibits good separation efficiency and reusability for emulsion separation. • TiO 2 @PDA@BiOBr is Z-scheme heterojunction with high photocatalytic efficiency. • PTPB-8 is capable of purifying biochemical oily wastewater with sunlight. Membrane separation technology is a promising alternative for oily wastewater purification. However, developing membrane for the purification of biochemical oily wastewater is still challengeable. To this aim, a novel multifunctional photocatalytic membrane of PTPB-8 is fabricated by sequentially loading of TiO 2 , polydopamine (PDA), and BiOBr onto polyacrylonitrile (PAN) nanofibers in situ. PTPB-8 is of water contact angle (WCA) ∼ 0° and underwater oil contact angle (UOCA) 154.7 ± 2.5°, allowing it with outstanding separation and anti-fouling capability, and good reusability for emulsion separation under gravity (i.e., separation efficiency >90 %, permeation flux >300 L m-2h−1, and flux recovery rate >82 % for n-hexane-in-water emulsion after 15 cycles). Under simulated solar light, the ternary heterojunction TiO 2 @PDA@BiOBr is catalytically active with generating active species and the charge transfer pathway follows the mechanism of Z-type heterojunction. Consequently, PTPB-8 can kill E. coli and S. aureus by ∼ 100 % and degrade tetracycline by >90 %. The application trial results have demonstrated the great potential of PTPB-8 in the purification of biochemical oily wastewater containing bacteria and antibiotics. This study will also give a new idea for enhancing the photocatalytic activity of heterojunctions by PDA decoration. [ABSTRACT FROM AUTHOR]

Ethylene (C 2 H 4) and pathogenic microorganisms are the two major causes of the deterioration of postharvest fruits and vegetables (F&V). Hence, the development of active packaging with C 2 H 4 scavenging and bactericidal activities is urgently desirable. Herein, a novel photocatalytic active film (CS-PC-AC) is developed for banana preservation by incorporating WO 3 /AgBr/Ag photocatalyst (PC) and activated carbon (AC) into chitosan (CS). The fabricated PC is a ternary Z -scheme heterojunction and its high photocatalytic activity is achieved by the bridge of Ag between WO 3 and AgBr through rapid transfer and separation of photogenerated electrons and holes. AC plays an indispensable role in the photocatalytic reaction through molecule adsorption and transport. PC and AC are hydrogen bonded with chitosan and their incorporation has slight effect on film's thermal stability but decreases the film's mechanical and barrier properties to some extent. CS-PC-AC exhibits strong bactericidal activity (killing ~100 % of Escherichia coli and Staphylococcus aureus within 3 h) and good C 2 H 4 scavenging activity (C 2 H 4 scavenging rate of 49 ± 2 %) under visible light irradiation, which can extend the banana shelf-life by at least 50 % at 25 °C. These results indicate the good perspective of CS-PC-AC in the delay of the deterioration of postharvest F&V. [Display omitted] [ABSTRACT FROM AUTHOR]

Currently, Janus membranes have attracted growing attention in oil-water separation due to the unique asymmetric wettability on opposite two surfaces. Nevertheless, it is still challengeable to achieve the superhydrophilicity and superhydrophobicity of the two opposite sides. Inspired by the lotus leaf and orange structure, the Janus membrane of polyacrylonitrile/poly (vinylidene fluoride)@poly (vinylidene fluoride)-methyltriethoxysilane (PAN/PVDF@PVDF-MTES) is developed by electrospinning and electrospraying technique for oil-water separation. In Janus membrane structure, each layer is physically combined, and the Janus-PAN side is superhydrophilic with water contact angle (WCA) of ∼0°, while the Janus-PVDF-MTES side is superhydrophobic with WCA of ∼170.2 ± 2.4°. These characteristics endow the membrane with outstanding separation efficiencies and good reusability. The separation mechanism is elucidated on the basis of the asymmetric wettability. The kinetics behavior of the oils in Janus membrane follows the models of pseudo-first-order and intra-particle diffusion. The oil flux of the Janus membrane is associated with the types of oil and the diffusion is not the only influence factor in oil adsorption. The application trial results indicate the potential of PAN/PVDF@PVDF-MTES membrane in the separation of the oil/water mixtures and surfactant-stabilized emulsions. [Display omitted] • A stragety of bionic Janus membrane of lotus leaf and orange structure is proposed. • Janus-PAN side is superhydrophilic with water contact angle of ∼0°. • Janus-PVDF-MTES side is superhydrophobic with water contact angle of ∼170.2 ± 2.4°. • Kinetics behavior of oils follows pseudo-first-order and intra-particle diffusion. • Janus membrane is highly efficient with good reusability for oil-water separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • PCL-EO@SF-BAs membrane is developed for food freshness monitoring and retaining. • BAs endow the membrane colorimetric response and antioxidant activity. • Antibacterial activity of the membrane is from the control released EO. • Directional water transport is generated from the bilayer asymmetric wettability. • Synergistic effect of directional water transport occurs on food shelf-life extending. Currently, designing smart membranes with multifunctional effectiveness is crucial to food freshness monitoring and retention. Herein, an active colorimetric Janus bilayer membrane with directional water transport (DWT) performance is constructed by electrospinning, which comprises a hydrophilic layer of silk fibroin-bayberry anthocyanins (SF-BAs) and a hydrophobic layer of polycaprolactone-eucalyptus oil (PCL-EO). The entities of BAs and EO are well dispersed in the fiber matrix by hydrogen bonds and physical interactions, respectively. BAs endow the membrane colorimetric response and antioxidant activity, and EO contributes to the antibacterial activity while DWT performance is generated from the asymmetric wettability of the two layers. The bilayer membrane has an accumulative one-way transport index of 1077%, an overall moisture management capacity of 0.76 and a water evaporation rate of 0.48 g h−1. Moreover, the release of BAs and EO was predominantly controlled by Fickian diffusion. As a pH-sensing indicator, PCL-EO@SF-BAs is highly sensitive to external pH stimuli and the response is reversible. In addition to freshness monitoring, PCL-EO@SF-BAs can extend the shelf-life of pork beyond 100% at 4 °C. Also, it can extend the shelf life of shrimp by approximately 70% at 25 °C with the synergistic effect of antibacterial activity and the DWT performance. [ABSTRACT FROM AUTHOR]

Zein electrospun nanofibers are widely used as the vehicles to load bioactive entities for release control; however, the water absorption of zein always restricts their applications in food preservation. In this work, an active hydrophobic membrane of peppermint oil (PO) loaded zein (ZN) with coating of methyltriethoxysilane (MTES) was developed for pork preservation. The fiber matrix of ZN was use for PO incorporation. The secondary structure of ZN and the feature of the relevant fibers are dependent on solvents of acetic acid and ethyl alcohol. In the composite structure, PO is hydrogen-bonded with ZN matrix; while the coating of MTES is bonded with fiber matrix by Si–O–C. The well-controlled release of PO predominantly follows the law of Fickian diffusion, endowing the membrane good antibacterial activity and antioxidant activity. The coating of MTES has no obvious influence on the bioactivities but provides the membrane outstanding hydrophobicity with water contact angle of 138 ± 5°. ZN-PO30-MTES can extend shelf life of pork by 100% (i.e., 24 h) at 25 °C, demonstrating its potential in food active packaging. [Display omitted] • An active hydrophobic electrospun membrane was developed for pork preservation. • Secondary structure of ZN and feature of fibers are dependent on solvents. • Release of peppermint oil from matrix is well controlled. • Coating of MTES endows membrane with water contact angle of 138 ± 5°. • Target membrane can effectively the extend shelf life of pork by 100% at 25 °C. [ABSTRACT FROM AUTHOR]

La is highly electrically affinitive for fluoride ions, but it is costly. Therefore, it is reasonable to mix it with cheap metals to form hybrid materials. On the other hand, calciniation process is usually needed in preparation of many adsorbents based on metal elements, which is energy and time consuming and not environment-friendly. In the present study, a novel Fe Mg La tri-metal nanocomposite was facilely prepared by co-precipitation without calcination. The role of individual metal in the tri-metal nanocomposite was illustrated. The samples were characterized by BET, SEM, TEM, Mapping EDS and XPS. Various influencing factors such as coexisting anions, pH and contacting time were studied in detail. Sorption isotherms showed that the sorption capacity of fluoride is 13.2 mg/g at the equilibrium fluoride concentration of 1 mg/L, and the maximum sorption capacity is 47.2 mg/g, indicating the high defluoridation performance of the adsorbent. The F − saturated adsorbent can be regenerated by alkaline and reused. Adsorption mechanism was analysized in detail, and the results indicated that F ions were able to substitute for all three metal-OH groups, and strong interactions happened between fluorion and the metals in the adsorption. The adsorption mechanism was speculated to be ligand exchange, which could be well supported by experimental results. The adsorbent is promising to treat fluoride polluted waters due to its high adsorption efficiency, low cost and easy operation. [ABSTRACT FROM AUTHOR]

An intelligent bionic trilayer fibrous membrane is developed via electrospinning for the moisture-adjusting of a storage space. The trilayer is composed of a hydrophobic inner layer of cellulose acetate (CA), a super hygroscopic intermediate layer of gelatin (GA) and a hydrophilic outer layer of ethylene-vinyl alcohol copolymer (EVOH). The hierarchical pore networks of EVOH/GA/CA (∼2.45/∼4.5/∼36.0 μm) and the asymmetry wettability endow the membrane with outstanding directional water transport capacity. Specifically, the membrane has an excellent accumulative one-way transport index (1293 %), a remarkable overall moisture management capacity (0.91) and a reasonably high water evaporation rate (0.59 g h−1). The target membrane can regulate the relative humidity (RH) from 75 % to 50 % without extra energy consumption, which is capable of extending the shelf-life of jerk beef by ∼100 % under surrounding temperature of 25 °C and humidity of 75 % RH. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Antimicrobial PDI pH-responsive film is developed via a facile casting method. • Incorporation of AE improves film mechanical strength, barrier and hydrophobicity. • Release of AE from matrix is pH-responsive and well controlled. • AE endows the film with PDI activity and antimicrobial activity. • Target film can effectively thwart Botrytis cinerea infection on cherry tomatoes. Using novel active food packaging has gradually become a daily necessity in terms of impeding microbial contamination. Here, an antimicrobial photodynamic inactivation (PDI) pH-responsive film is developed by incorporating aloe-emodin (AE) into a vehicle of gelatin/chitosan (GC). Besides enhancement in hydrophobicity, the well-dispersed crystals of AE in the GC matrix by hydrogen bonding can upgrade the film's mechanical strength and barrier. The matrix is capable of regulating the release of AE in response to acidic stimuli by a combination mechanism of diffusion and polymer relaxation. Being benefitted from the inherent bioactivity of AE and the PDI activity under visible light irradiation (i.e., 456 nm), the target film of GC-AE2 has excellent antibacterial effect towards Staphylococcus aureus and Escherichia coli , showing bacterial viability of 9.93 ± 1.33 % and 14.85 ± 1.16 %, respectively. Furthermore, the film can effectively thwart Botrytis cinerea infection in cherry tomatoes, demonstrating its potential in preventing the microbial spoilage of postharvest fruits. [ABSTRACT FROM AUTHOR]

As a natural pH-sensing colorant, purple sweet potato anthocyanins (PSPAs) have demonstrated great potential in colorimetric film for freshness monitoring. However, the photothermal instability of PSPAs is still a challengeable issue. Herein, γ-cyclodextrin metal-organic framework (CD-MOF) loaded with PSPAs (PSPAs@CD-MOF, i.e., PM) and eugenol (EUG) were incorporated in cellulose acetate (CA) matrix for developing a smart active colorimetric film of CA/PM/EUG, where PM and EUG were hydrogen-bonded with CA. Attentions were focused on the photothermal colorimetric stability, colorimetric response, and antibacterial activity of the films. The presence of PM and EUG endowed the film outstanding UV-blocking performance and enhanced the barrier against water vapor and oxygen. Target film of CA/PM15/EUG10 had good photothermal colorimetric stability due to the protection of CD-MOF on PSPAs and the color changes with pH-stimuli were sensitive and reversible. In addition to antioxidant activity, CA/PM15/EUG10 had antibacterial activity against Escherichia coli and Staphylococcus aureus. The application trial results indicated that the CA/PM15/EUG10 was valid to indicate pork freshness and extended the shelf-life by 100 % at 25 °C, which has demonstrated a good perspective on smart active packaging for freshness monitoring and shelf-life extension. • γ-Cyclodextrin metal-organic framework is fabricated for anthocyanin protection. • Target film has good photothermal colorimetric stability. • Colorimetric response of target film is sensitive and reversible. • Monitoring pork freshness and extending its shelf-life by 100% at 25 °C • Freshness monitoring and shelf-life extension are realized concurrently. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cross-linking improves the barrier and water resistance of casted film. • Casted film is pH-sensitive and reversible in color changes. • Electrospun membrane is antibacterial and release controllable. • Antioxidant activity is sourced from the released linalool. • Highly reliable milk freshness monitoring and double shelf-life extending at 25 °C. Colorimetric active double-layer composites of film@membrane were developed via direct electrospinning functional nanofibers on colorimetric film. In the structure, oxidized sodium alginate cross-linked carboxymethyl chitosan (CO) was used as colorimetric film matrix to incorporate the anthocyanins extract from Oxalis triangularis ssp. papilionacea (OTA); while the blend of gelatin/zein (GZ) was used as fibrous matrix for linalool (L) encapsulation. Besides good barrier and water resistance, the outer-layer of CO-OTA showed colorimetric sensitivity towards pH-stimuli with reversible color changes. The inner-layer of GZ-L exhibited good antibacterial activities against Staphylococcus aureus and Escherichia coli. The volatile release of L from fibrous matrix was well controlled and mainly followed Fickian diffusion. Moreover, the antioxidant activity of the composites is source from the released linalool. The high reliability on milk freshness monitoring and double shelf-life extending at 25 °C suggest the potential of CO-OTA@GZ-L in colorimetric active food packaging. [ABSTRACT FROM AUTHOR]