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Considering the environmental impact and health risks caused by oily wastewater in the petrochemical industry, it is crucial to develop more efficient separation techniques than traditional methods, such as membrane separation, for treating stable emulsions enriched with natural surfactants. This study investigated the preparation of dense cellulose acetate membranes from a low-cost biomass precursor ( Luffa cylindrica ) and their modification with graphene oxide (GO) and TiO 2 nanoparticles, aiming to obtain a polymeric nanocomposite with good flux characteristics and selectivity for the treatment of oil/water emulsions. The materials obtained were characterized using techniques such as X-ray diffraction, nuclear magnetic resonance spectroscopy, infrared absorption spectroscopy, along with optical and scanning electron microscopy, among others. The membranes were prepared by the casting technique and modified with the above-mentioned nanostructured materials. Flux analyses with petroleum emulsion revealed that membranes modified with GO and TiO 2 nanoparticles showed significant improvements in antifouling resistance compared to unmodified membranes. These enhanced properties highlight the potential of modified cellulose acetate membranes for application in industrial wastewater treatment., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Coumarins have great pharmacotherapeutic potential, presenting several biological and pharmaceutical applications, like antibiotic, fungicidal, anti-inflammatory, anticancer, anti-HIV, and healing activities, among others. These molecules are practically insoluble in water, and for biological applications, it became necessary to complex them with cyclodextrins (CDs), which influence their bioavailability in the target organism. In this work, we studied two coumarins, and it was possible to conclude that there were structural differences between 4,7-dimethyl-2 H -chromen-2-one (DMC) and 7-methoxy-4-methyl-2 H -chromen-2-one (MMC)/β-CD that were solubilized in ethanol, frozen, and lyophilized (FL) and the mechanical mixtures (MM). In addition, the inclusion complex formation improved the solubility of DMC and MMC in an aqueous medium. According to the data, the inclusion complexes were formed and are more stable at a molar ratio of 2:1 coumarin/β-CD, and hydrogen bonds along with π-π stacking interactions are responsible for the better stability, especially for (MMC) 2 @β-CD. In vivo wound healing studies in mice showed faster re-epithelialization and the best deposition of collagen with the (DMC) 2 @β-CD (FL) and (MMC) 2 @β-CD (FL) inclusion complexes, demonstrating clearly that they have potential in wound repair. Therefore, (DMC) 2 @β-CD (FL) deserves great attention because it presented excellent results, reducing the granulation tissue and mast cell density and improving collagen remodeling. Finally, the protein binding studies suggested that the anti-inflammatory activities might exert their biological function through the inhibition of MEK, providing the possibility of development of new MEK inhibitors.

Palm seedlings are visually selected from mature fruits in a slow process that leads to nonuniform germination and high embryo mortality. In this study, we determined the levels of monosaccharides, their crystallinity, and their role in the formation of Euterpe edulis endosperm during seed maturation. Seeds harvested from 108 to 262 days after anthesis (DAA) were analyzed morphologically, physiologically, and chemically to measure soluble and insoluble lignins, ashes, structural carbohydrates, degree of crystallinity, and endo-β-mannanase. The seeds achieved maximum germination and vigor at 164 DAA. During the early stages, only compounds with a low structural order were formed. The contents of soluble and insoluble lignins, ashes, glucans, and galactans decreased during maturation. Those of mannans, the main structural carbohydrate in the endosperm, increased along with the degree of crystallinity, as suggested by a mannan-I-type X-ray diffraction pattern. Similarly, endo-β-mannanase activity peaked at 262 DAA. The superior physiological outcome of seeds and seedlings at 164 DAA implies a 98-day shorter harvesting time. The state of mannans during seed maturation could be used as a marker to improve seedling production by E. edulis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Many previous studies presented the effectiveness of ketoconazole (KTZ) against leishmaniasis. However, the bioavailability and therapeutic efficacy of free KTZ are limited due to its low aqueous solubility. In this study, an inclusion complex (IC6HKTZ) was prepared with p-sulfonic acid calix[6]arene (CX6SO 3 H) to improve the solubility and efficacy of KTZ against Leishmania amazonensis and Leishmania infantum promastigotes. A linear increase in KTZ solubility as a function of CX6SO 3 H concentration was verified using the phase-solubility diagram. The resulting diagram was classified as A L -type and a 1:1 host-guest stoichiometry was assumed to prepare IC6HKTZ by freeze-drying. FTIR, TG/DSC, XRD, and solid-state 13 C NMR spectroscopy analyses were performed to confirm the formation of IC6HKTZ. The solubility enhancement of KTZ by 120.00 μM CX6SO 3 H was about 95 times. The IC 50 values of IC6HKTZ and free KTZ were 3.95 and 14.35 μM for Leishmania amazonensis and 6.74 and 17.47 μM for Leishmania infantum, respectively. The viability of DH82 macrophages was not affected by CX6SO 3 H. These results show that CX6SO 3 H is a new supramolecular carrier system that improves antileishmanial activities to KTZ for the treatment of cutaneous and visceral leishmaniasis., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [Vagner T. de Queiroz reports financial support was provided by Foundation for Research Support of Espírito Santo. Bianca de O. Botelho reports financial support was provided by Coordination of Higher Education Personnel Improvement. Natalia A. Guedes reports financial support was provided by Coordination of Higher Education Personnel Improvement. Diana C. Cubides-Roman reports financial support was provided by Foundation for Research Support of Espírito Santo. Vagner T. de Queiroz reports a relationship with Federal University of Espirito Santo that includes: employment.]., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Phosphorus-containing graphene-based hybrids are materials with outstanding properties for diverse applications. In this work, an easy route to produce phosphorus-graphene oxide hybrid materials is described, involving the use of variable amounts of H 3 PO 4 and H 2 SO 4 during the reaction of oxidation of a graphitic precursor. The physical and chemical features of the hybrids change significantly with the variation in the acid amounts used in the syntheses. XPS and solid-state 13 C and 31 P NMR results show that the hybrids contain large amounts of oxygen functional groups, with the phosphorus incorporation proceeding mostly through the formation of phosphate-like linkages and other functions with C-O-P bonds. The experimental findings are supported by DFT calculations, which allow the assessment of the energetics and the geometry of the interaction between phosphate groups and graphene-based models; these calculations are also used to predict the chemical shifts in the 31 P and 13 C NMR spectra of the models, which show good agreement with the experimentally observed solid-state NMR spectra.

The photo-Fenton activity of graphitic carbon nitride (g-C 3 N 4 ) has been widely studied, nevertheless, its Fenton-like catalytic behavior in the dark has not yet been demonstrated. In the present work, it is shown that oxygenated g-C 3 N 4 obtained at different temperatures (500-600 °C) can degrade indigo carmine with hydrogen peroxide in the dark by a reaction similar to a conventional Fenton's reaction. Based on an extensive characterization of g-C 3 N 4 , we conclude that Fenton-like activity is directly related to the oxygenated functional groups on g-C 3 N 4 structure, mainly by -OH functional groups. Oxygenated functional groups (e.g., hydroquinone-like groups) can reduce the H 2 O 2 and generate oxidizing hydroxyl radicals, just like in the Fenton reaction performed by metals. In addition to new information on g-C 3 N 4 surface reactivity revealed by this study, the metal-free oxygenated g-C 3 N 4 catalyst may be an alternative to traditional metal catalysts used in Fenton-like reactions for advanced oxidation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The hydrothermal synthesis of nano-faujasite has been successfully performed and the effects of some crystallization parameters were investigated, along with the use of this material as a heavy-metal ion adsorbent. X-ray diffraction patterns have shown that the structure of the nano-faujasite is strongly dependent on both the crystallization time and the alkalinity of the synthesis medium. According to N 2 physisorption, X-ray fluorescence, SEM/EDS, and solid state 29 Si and 27 Al NMR data, the produced nano-faujasite consists of a solid with low molar Si/Al ratio (1.7), with high availability of ion exchange sites and high surface area/small particle size, allowing easy diffusion of metal ions to adsorbent active sites. As a consequence, an excellent performance on removal of Cd 2+ , Zn 2+ and Cu 2+ ions was found for this solid. The adsorption capacity followed the order Cd 2+ (133 mg·g -1 ) > Zn 2+ (115 mg·g -1 ) > Cu 2+ (99 mg·g -1 ), which agrees with the order of increasing absolute values of the hydration energy of the metal ions. Kinetic studies and adsorption isotherms showed that the metal ion removal takes place by ion exchange on the monolayer surface of the nano-faujasite. The electrochemical recovery of copper in metallic form exhibited an efficiency of 80.2% after 120 min, which suggests that this process can be adequately implemented for full-scale metal removal.

The discovery of new drugs and dosage forms for the treatment of neglected tropical diseases, such as human and animal leishmaniasis, is gaining interest in the chemical, biological, pharmaceutical, and medical fields. Many pharmaceutical companies are exploring the use of old drugs to establishing new drug dosage forms and drug delivery systems, in particular for use in neglected diseases. The formation of complexes with cyclodextrins is widely used to improve the stability, solubility, and bioavailability of pharmaceutical drugs, as well as reduce both the toxicity and side effects of many of these drugs. The aim of this study was to characterize solid compounds obtained from the association between furazolidone (FZD) and β-cyclodextrin (β-CD) or hydroxypropyl-β-cyclodextrin (HP-β-CD). The solid compounds were prepared in molar ratios of 1:1 and 1:2 (drug:CD) by kneading and lyophilization. Molecular docking was used to predict the preferred relative orientation of FZD when bound in both studied cyclodextrins. The resulting solid compounds were qualitatively characterized by scanning electron microscopy (SEM), thermal analysis (DSC and TG/DTG), X-ray diffraction (XRD), Raman spectroscopy with image mapping (Raman mapping), and 13 C nuclear magnetic resonance spectroscopy ( 13 C NMR) in the solid state. The cytotoxicity of the compounds against THP-1 macrophages and the 50% growth inhibition (IC 50 ) against Leishmania amazonensis promastigote forms were subsequently investigated using in vitro techniques. For all of the solid compounds obtained, the existence of an association between FZD and CD were confirmed by one or more characterization techniques (TG/DTG, DSC, SEM, XRD, RAMAN, and 13 C NMR), particularly by a significant decrease in the crystallinity of these materials and a reduction in the melting enthalpy associated with furazolidone thermal events. The formation of more effective interactions occurred in the compounds prepared by lyophilization, in a 1:2 molar ratio of the two CDs studied. However, the formation of an inclusion complex was confirmed only for the solid compound obtained from HP-β-CD prepared by lyophilization (LHFZD1:2). The absence of cytotoxicity on the THP-1 macrophage lineages and the leishmanicidal activity were confirmed for all compounds. MHFZD1:2 and LHFZD1:2 were found to be very active against promastigote forms of L. amazonensis, while all others were considered only active. These results are in line with the literature, demonstrating the existence of biological activity for associations between drugs and CDs in the form of complexes and non-complexes. All solid compounds obtained were found to be promising for use as leishmanicidal agents against promastigote forms of L. amazonensis.

The current study aimed obtaining antimicrobial sachets that could be used as preservatives for foods. Basil (BEO) and Pimenta dioica (PDEO) essential oils (EOs) were analyzed by GC-FID and GC-MS and tested against the foodborne bacteria S. aureus, E. coli, L. monocytogenes, P. aeruginosa, S. Enteritidis, and the food-spoilage mold B. nivea. Then, inclusion complexes (ICs) with EOs and β-cyclodextrin (β-CD) were prepared as a strategy to reduce volatility and increase the release time of EOs. Eight ICs were prepared by kneading and freeze-drying methods, in two molar ratios, and have been characterized by complementary methods: FT-IR, thermal analysis (DSC and TG/DTG), powder XRD, and solid state 13 C NMR. In vitro antimicrobial activities of ICs, both dispersed in agar and loaded in sachets, have also been investigated. Complexation was confirmed for all samples. PDEO-based ICs prepared by kneading method, at both molar ratios, displayed better in vitro antimicrobial activity. The obtained results strongly suggest a potential application of these ICs as natural antimicrobials., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Lignocellulosic biomass has been widely studied as a source of cellulose- and related products, attracting the great interest of researchers dealing with renewable energy sources, vegetable waste recycling and biomaterials. In this work, the babassu coconut shells (epicarp and endocarp) were used for the achievement of products such as cellulose, cellulose acetate and cellulose-silica composite, which were chemically and structurally characterized by solid-state 13C nuclear magnetic resonance spectroscopy and scanning electron microscopy, among other techniques. As this precursor also naturally contains a significant amount of silica, a composite containing cellulose fibers mixed with amorphous silica particles (with rosette-like shape) was also produced. Finally, the possibility of synthesis of cellulose acetate was also demonstrated, illustrating the plethora of potential applications of this important lignocellulosic residue for the production of cellulose-based materials of high technological interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A simple and straightforward method using microwave-assisted reactions is presented for the functionalization of graphene oxide with aromatic and non-aromatic amines, notedly dibenzylamine (DBA), p -phenylenediamine (PPD), diisopropylamine (DPA) and piperidine (PA). The as-synthesized amine-functionalized graphene oxide materials (amine-GO) were characterized using spectroscopic techniques including XRD, FTIR, 13 C NMR, XPS, TEM for imaging and thermogravimetric analysis (TGA). The characterization confirmed the functionalization for all amines, reaching relatively high surface nitrogen atomic concentrations of up to 8.8%. The investigations of electrochemical behavior for the amine-GOs show the significant improvement in GO's electrochemical properties through amine functionalization, exhibiting long life cycle stability and reaching specific capacitance values of up to 290 F g -1 and 260 F g -1 for GO-PA and GO-DPA samples, respectively, confirming their potential application as alternative supporting materials in supercapacitors., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)