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Microcystin-LR (MC-LR), a potent hepatotoxin can cause liver damages. However, research on hepatic lipid metabolism caused by long-term exposure to environmental concentrations MC-LR is limited. In the current study, mice were exposed to various low concentrations of MC-LR (0, 1, 30, 60, 90, 120 μg/L in the drinking water) for 9 months. The general parameters, serum and liver lipids, liver tissue pathology, lipid metabolism-related genes and proteins of liver were investigated. The results show that chronic MC-LR exposure had increased the levels of triglyceride (TG) and total cholesterol (TC) in serum and liver. In addition, histological observation revealed that hepatic lobules were disordered with obvious inflammatory cell infiltration and lipid droplets. More importantly, the mRNA and proteins expression levels of lipid synthesis-related nuclear sterol regulatory element binding protein-1c (nSREBP-1c), SREBP-1c, cluster of differentiation 36 (CD36), acetyl-CoA-carboxylase1 (ACC1), stearoyl-CoA desaturase1 (SCD1) and fatty acid synthase (FASN) were increased in MC-LR treated groups, the expression levels of fatty acids β-oxidation related genes peroxisomal acyl-coenzyme A oxidase 1 (ACOX1) was decreased after exposure to 60–120 μg/L MC-LR. Furthermore, the inflammatory factors interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) were higher than that in the control group. All the findings indicated that mice were exposed to chronic low concentrations MC-LR caused liver inflammation and hepatic lipid metabolism disorder. [Display omitted] • Mice were exposed to MC-LR at environmental concentrations for 9 months. • 30–120 μg/L MC-LR in the drinking water caused liver steatosis. • MC-LR (starting at 1 μg/L) affected the expression of lipid synthesis and β-oxidation. • Chronic MC-LR exposure increased the expression of IL-6 and TNF-α and caused liver inflammation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ternary 3D "PIZZA"-like Bi 2 MoO 6 -TiO 2 /diatomite composite was synthesized. • An adsorption-photocatalysis system was constructed by the instruction of diatomite. • Excellent photocatalytic mineralization property of HCHO was obtained under visible light. • The effect of water on the mineralization of HCHO was studied via in-situ DRIFTs analysis. • The O 2 and H 2 O molecules were involved in the photocatalytic mineralization process of HCHO. The application of TiO 2 -based photocatalysts in air pollution control has attracted much attention thanks to their advantageous green and sustainable performance. However, how to improve the degradation efficiency under visible light is still challenging. Herein, we report a ternary three-dimensional "PIZZA"-like Bi 2 MoO 6 -TiO 2 /diatomite (BTD) composite with high-efficient mineralization and recycling performance towards gaseous formaldehyde (HCHO) under visible light. The high-efficient adsorption-photocatalysis collaborative system with intimate interface combination is successfully established among Bi 2 MoO 6 (BMO), TiO 2 and diatomite. The HCHO mineralization rate constant of BTD-1:2 composite is up to around 4.03 times and 2.18 times higher than those of bare BMO and binary Bi 2 MoO 6 -TiO 2 composite, respectively. It is indicated that the introduction of diatomite increases active sites and plays the vital role in the improvement of photocatalysis. In addition, the photogenerated holes (h+) and hydroxyl radical (OH) are proved to be the main active species for HCHO mineralization. Furthermore, there is a competitive adsorption relationship between water (H 2 O) molecules and HCHO molecules, and both H 2 O molecules and oxygen (O 2) molecules participated in the reaction of HCHO mineralization based on in-situ DRIFTs spectra analysis. Our work would give a new perspective on gaseous HCHO purification. [ABSTRACT FROM AUTHOR]

Highlights: [•] An Arizona Ca-montmorillonites was modified with DDDMA through direct ion exchange. [•] The obtained organoclays were characterized by XRD, TEM, TG, and hot stage IES. [•] The structural geometry and thermal properties of organoclays were studied. [•] Organic SAz-2 Ca-montmorillonites showed potential prospects in the polymer industry. [ABSTRACT FROM AUTHOR]

Highlights: [•] TiO2/AST composite was synthesized by hydrolysis–deposition method. [•] The composite was characterized by SEM, TEM, XRD, EDS, XPS, and FTIR. [•] TiO2 particles coated on AST were mixed crystal phases of rutile and anatase. [•] TiO2/AST composite showed good photocatalytic activity for the removal of Cr(VI). [ABSTRACT FROM AUTHOR]

Novel oxygen vacancy-rich amorphous TiO 2 -BiOBr-sepiolite composite with enhanced photocatalytic removal for indoor HCHO and oxytetracycline under visible light was successfully fabricated by a facile one-pot solvothermal method. This work could provide a new insight for designing and constructing highly active photocatalysts for the practical elimination of pharmaceutical and personal care products (PPCPs) as well as volatile organic compounds (VOCs). • Novel oxygen vacancy-rich amorphous TiO 2 -BiOBr-sepiolite composite was synthesized. • The composite shows superior photodegradation efficiency towards HCHO and oxytetracycline. • The photocatalytic process is mainly governed by the photoinduced holes. • Potential mechanisms for the enhanced activity of composite were analyzed. • The plausible degradation pathway for oxytetracycline was proposed. Herein, a novel oxygen vacancy-rich amorphous TiO 2 -BiOBr-sepiolite composite was synthesized through a facile one-pot solvothermal method. Under visible light, it exhibited enhanced adsorption and photocatalytic removal activity towards gaseous formaldehyde, whose reaction rate constant is nearly 11.75, 3.44, 1.69, 2.18 and 6.27 times higher than those of amorphous TiO 2 , BiOBr, TiO 2 -BiOBr, oxygen vacancy-poor composite and P25, respectively. Moreover, it also displayed significantly improved photodegradation performance towards oxytetracycline under visible light. The improved photocatalytic activity is mainly ascribed to the synergy between the ternary heterogeneous structure and introduced oxygen vacancy, leading to the superior adsorption performance, extended visible-light adsorption scope and faster carriers' separation rate. The photogenerated holes are the dominant active species during the reaction process. Additionally, a plausible photocatalytic degradation pathway for oxytetracycline was also proposed. In general, this work provides a viable strategy of visible-light-driven photocatalyst for practical environmental remediation of indoor volatile organic compounds (VOCs) and pharmaceuticals and personal care products (PPCPs). [ABSTRACT FROM AUTHOR]

• Organo-montmorillonites (NZMts) modified by binary surfactant mixtures were synthesized. • The NZMts exhibit enhanced detoxification efficiency for both AFB1 and ZER. • The adsorption enhancement mechanism of NZMts was proposed. • This study provides new insight for multifunctional mycotoxin adsorbents. To solve the problem of simultaneous adsorption of polar and weak polar mycotoxins, organo-montmorillonites modified by binary surfactant mixtures (NZMts), including polyoxyethylene ether (OP-10) and lauramidopropyl betaine (LAB-35), were synthesized for the simultaneous removal of aflatoxin B 1 (AFB 1) and zearalenone (ZER). The microstructure, interface and pore structure characteristics of NZMts were investigated through different technologies. The results show that the obtained NZMts modified by binary surfactant mixtures have different structural configurations, higher carbon content and stronger hydrophobicity compared with organo-montmorillonites modified by single surfactant. More importantly, the obtained adsorbents show significant improvements on the detoxification efficiency of both AFB 1 and ZER. The pH has less effect on the adsorption of NZMts compared with the control samples modified by single surfactant, suggesting that NZMts are more stable in different pH environments. In addition, the adsorption mechanisms of NZMts to AFB 1 and ZER were proposed based on the characterizations and adsorption isotherms. It is indicated that NZMts combines with AFB 1 mainly through the hydrophobic interaction and ion dipole action, while with ZER mainly through hydrophobic interaction. The as-received NZMts with more hydrophobic property effectively enhance the adsorption capacities of weak polar and non-polar mycotoxins, providing a new orientation for multifunctional mycotoxin adsorbents. [ABSTRACT FROM AUTHOR]

• Novel BiOCl/TiO 2 /clinoptilolite composite photocatalyst was synthesized. • BiOCl/TiO 2 /clinoptilolite displayed excellent visible photocatalytic activity. • Carrier effect and heterojunction charged for photocatalytic enhancement. • This study provides a novel idea for ternary heterojunction construction. Novel BiOCl/TiO 2 /clinoptilolite composite was prepared via a homogeneous precipitation and calcination-crystallization process in this study. Through structural design and spatial assembly, the ternary composite based on clinoptilolite layer as well as the TiO 2 nano particles and BiOCl nano sheets was successfully synthesized. The prepared composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS), N 2 isothermal adsorption-desorption test and electrochemical measurement, respectively. Compared with bare photocatalysts (i.e. TiO 2 and BiOCl), the composite exhibited enhanced photoactivity under visible light irradiation towards rhodamine B (RhB). Based on the pseudo-first-order kinetic constants, the photocatalytic performance of BiOCl/TiO 2 /clinoptilolite composite is around 48 and 11 times higher than that of pure TiO 2 and BiOCl, respectively. The enhanced photocatalytic properties of the composite should be attributed to the improved adsorption ability and the formation of the n -p heterojunction between BiOCl and TiO 2 , which is beneficial to establish the rapid adsorption-desorption system and promote the efficient separation of the photogenerated electron-hole pairs. The excellent visible-light-driven performance makes the BiOCl/TiO 2 /clinoptilolite composite possible to be utilized in the field of industrial wastewater treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Novel ternary heterogeneous BiOCl/TiO 2 /sepiolite composite with enhanced visible-light-induced photoactivity towards TC was successfully fabricated by a mild hydrolysis precipitation method followed by the calcination crystallization process. The present study would inspire the exploration of similar novel design to synthesize other highly efficient visible-light photocatalysts for better applications in addressing environmental pollution issues. Abstract In this study, the novel ternary heterogeneous BiOCl/TiO 2 /sepiolite composite with enhanced visible-light-induced photocatalytic activity was synthesized via the hydrolysis precipitation method followed by a calcination crystallization process. The as-prepared samples were characterized by X-ray diffraction (XRD), UV–VIS diffused reflectance spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL), respectively. Compared with bare BiOCl and TiO 2 , the ternary heterogeneous structure in BiOCl/TiO 2 /sepiolite significantly improved the visible-light-induced photocatalytic performance towards tetracycline (TC), and also contributed to the separation efficiency and recyclability of the photocatalyst. In addition, the influence of the mass ratio of BiOCl in the composites was also discussed, and the optimal mass ratio is identified as 50% (m BiOCl /(m TiO2 + m BiOCl). Furthermore, TC degradation by-products were further detected by HPLC-MS/MS, and a possible degradation pathway was proposed. Besides, ESR (Electron spin resonance) results indicated that the main active radical species were photo-induced holes (h+) and superoxide radical (O 2 −) in the TC degradation process. Hence, the enhanced photocatalytic activity of the prepared ternary composite was mainly attributed to the remarkable synergistic effect within the BiOCl/TiO 2 /sepiolite ternary heterogeneous system, resulting in the superior adsorption activity, the outstanding visible-light response performance and the efficient separation of the photogenerated electron-hole pairs. It is speculated that the novel ternary heterogeneous BiOCl/TiO 2 /sepiolite composite would have a broad application prospect in the field of wastewater treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Novel CH 3 COOH functionalized TiO 2 /kaolinite composite was facilely prepared through a typical sol-gel method modified with CH 3 COOH treatment. Weak acid (CH 3 COOH) was utilized to activate the TiO 2 surface and generate more hydroxyl groups. Taken ciprofloxacin (CIP) as the target pollutant, both strongest adsorption ability and highest degradation efficiency were obtained compared with bare TiO 2 or TiO 2 /kaolinite composite under UV light and visible light, especially under UV light. Furthermore, density functional theory (DFT) calculations demonstrated that CH 3 COOH treatment might exert effect towards the transition and lifetime of electrons as well as contribute to the enhancement of the reactivity ability of TiO 2 and increase the catalytic properties. Enhancement mechanism and possible radicals' migration pathway was illustrated based on the characterizations (i.e. XRD, BET, UV–Vis, FTIR, Raman, etc.). Our study provides new insights into composite photocatalysts' surface adjustment and functional groups construction based on natural minerals. Highlights • Acetic acid was used to functionalize the TiO 2 /kaolinite surface. • Enhanced photocatalytic activity for ciprofloxacin within broad light spectrum was obtained. • DFT was used to explore the interface effect and the hydrogen function. • The enhancement mechanism was elucidated in this work. • This study provides novel idea for the synthesis of photocatalysts based on natural minerals. Abstract In this study, sol-gel method modified with acetic acid (CH 3 COOH) was employed to facilely synthesize hydrogen functionalized TiO 2 /kaolinite composite. Weak acid (CH 3 COOH) was used to modify the surface of TiO 2 /kaolinite composite in order to activate TiO 2 surface and generate more hydroxyl groups. The modified surface can act as Lewis acid sites to allow the physisorption of uncharged carboxyl acid groups, which is believed to be beneficial for electron injection and transfer. Using ciprofloxacin (CIP) as the target pollutant, in comparison with the use of strong acid such as hydrochloric acid (HCl) or sulfuric acid (H 2 SO 4), it was found that CH 3 COOH functionalized TiO 2 /kaolinite composite possessed the strongest adsorption ability and exhibited highest degradation efficiency under broad spectrum (200–800 nm). Moreover, the concentration of CH 3 COOH required is low (0.1 mol/L) in this work. The results show that the CH 3 COOH treated sample exhibited much higher degradation rates than bare TiO 2 or TiO 2 /kaolinite composite under both UV light and visible light. The kinetic constants under UV light were almost 2.61 and 1.57 times higher than those of TiO 2 and TiO 2 /kaolinite, respectively. According to the X-ray diffraction (XRD), N 2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared spectroscopy (FTIR) as well as Raman characterization results, it is revealed that the improved photocatalytic activity can be mainly attributed to the CH 3 COOH functionalization towards the TiO 2 /kaolinite composite. Furthermore, density functional theory (DFT) calculations were employed to explore the interface effect between TiO 2 and kaolinite as well as the function of newly introduced hydrogen on the surface of the composite, which significantly contributes to better understanding the function of CH 3 COOH in the constructed system. On the other hand, electron spin resonance (ESR) analysis suggests that the main oxidation species in the degradation process under broad light spectrum illumination was the holes. This study also provides information about the enhancement mechanism. New insights in photocatalysts synthesis and properties adjustment based on natural minerals for the elimination of organic contaminants of emerging concern in water was successfully introduced in the present study. [ABSTRACT FROM AUTHOR]

This work aims at exploring the potential of nonionic surfactant octylphenol polyoxyethylene ether (OP-10) modified montmorillonites (NMts) as mycotoxins adsorbent. The resulting NMts has different structural configurations, organic carbon contents, surface hydrophobicity and textural properties at different surfactant loadings. The prepared NMts were used for adsorption of polar aflatoxin B 1 (AFB 1 ) and weak polar zearalenone (ZER) in both single and binary-contaminate systems by simulating conditions of gastrointestinal tract. The adsorption capacities of NMts to AFB 1 and ZER increased up to 2.78 and 8.54 mg/g respectively from 0.51 and 0.00 mg/g of raw montmorillonite (Mt). High adsorption capacities of NMts to AFB 1 and ZER could be reached at low surfactant loadings. There was little decrease from pH of 3.5 to 6.5 but became negligible with increasing the surfactant loadings. In binary-contaminate adsorption system, the adsorption of ZER was obviously affected by the existence of AFB 1 , while ZER had little effect on the adsorption process of AFB 1 due to different adsorption mechanism. This study demonstrates that NMts could be a promising adsorbent for simultaneous detoxification of polar and non-polar mycotoxins. [ABSTRACT FROM AUTHOR]

To overcome rapid electron-hole recombination and low adsorption capacity of single g-C 3 N 4 photocatalyst, the present work reports on the fabrication of two kinds of visible-light-driven composite photocatalysts (g-C 3 N 4 /kaolinite and g-C 3 N 4 /illite composites). 2D/2D assembly was successfully achieved in this work. Furthermore, the as-synthesized composites exhibited significantly enhanced photocatalytic activity under visible-light irradiation, whose reaction rate constants were almost 4.13 times (g-C 3 N 4 /kaolinite) and 3.18 times (g-C 3 N 4 /illite) that of pure g-C 3 N 4 . A plausible reaction mechanism over the as-prepared composite photocatalysts was also proposed based on the experimental results obtained. The photocatalytic enhancement of synthesized composites should be attributed to the intimate interface contact between g-C 3 N 4 and layered minerals, resulting in better dispersion performance, higher charge separation efficiency as well as stronger adsorption ability. [ABSTRACT FROM AUTHOR]

Organo-montmorillonites (OMts) modified with mono- and di-alkyl cationic surfactants were prepared to remove polar mycotoxin aflatoxin B 1 (AFB 1 ) and weak polar, hydrophobic mycotoxin zearalenone (ZER) simultaneously. The structural and surface properties of the prepared OMts were investigated. In vitro adsorption experiments were carried out to simulate the in vivo conditions of gastrointestinal tract of animals by a batch mode. The adsorption of AFB 1 and ZER in both single and binary-contaminate systems were investigated systematically. Both OMts showed super enhanced adsorption capacities towards AFB 1 and ZER whenever in single and binary-contaminate systems compared with raw Mt, indicating the effectiveness of the prepared OMts acted as mycotoxins adsorbents. DODAC-Mt showed a higher adsorption capacity towards AFB 1 and ZER than OTAB-Mt. The equilibrium data of AFB 1 on OMts were fitted satisfactorily with Freundlich and Linear models, suggesting the co-existence of different adsorption mechanism which were proposed to be ion–dipole interactions (between surfactant cations and carbonyl groups of AFB 1 ) and adsorption/partition mechanisms. The adsorption isotherms of OMts to ZER matched best with Linear models, implying the adsorption/partition mechanism. For simultaneous adsorption, the adsorption process of one mycotoxin was slightly affected by the presence of the other mycotoxin due to the requirement of partial same sorption sites. In addition, the solution pH had negligible influence on the adsorption process of OMts, meaning no desorption occurred when the adsorbents pass through from stomach to intestine as animal feed. [ABSTRACT FROM AUTHOR]

Diatomite, a porous non-metal mineral, was used as support to prepare TiO 2 /diatomite composites by a modified sol–gel method. The as-prepared composites were calcined at temperatures ranging from 450 to 950 °C. The characterization tests included X-ray powder diffraction (XRD), scanning electron microscopy (SEM) with an energy-dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption/desorption measurements. The XRD analysis indicated that the binary mixtures of anatase and rutile exist in the composites. The morphology analysis confirmed the TiO 2 particles were uniformly immobilized on the surface of diatom with a strong interfacial anchoring strength, which leads to few drain of photocatalytic components during practical applications. In further XPS studies of hybrid catalyst, we found the evidence of the presence of Ti–O–Si bond and increased percentage of surface hydroxyl. In addition, the adsorption capacity and photocatalytic activity of synthesized TiO 2 /diatomite composites were evaluated by studying the degradation kinetics of aqueous Rhodamine B under UV-light irradiation. The photocatalytic degradation was found to follow pseudo-first order kinetics according to the Langmuir–Hinshelwood model. The preferable removal efficiency was observed in composites by 750 °C calcination, which is attributed to a relatively appropriate anatase/rutile mixing ratio of 90/10. [ABSTRACT FROM AUTHOR]