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Two new vitrimeric materials have been studied for potential additive manufacturing applications such as 3Dprinting. A monomer containing disulfide bonds and beta-hydroxyesters was easily synthesized from two lowcost and commercially available reagents. Another disulfide-containing monomer was synthesized for comparison purposes. Materials were prepared through a UV-light radical polymerization of methacrylates. The addition of two reactive diluents such as poly(ethylene glycol) methyl ether methacrylate (PEGMA) and ethylene glycol phenyl ether methacrylate (EGPMA) was necessary to achieve a suitable viscosity for the curing as well as for their printability. The curing process was controlled by FTIR. Thermomechanical properties were investigated by means of DMTA analysis revealing near-ambient T-g values. Stress relaxation tests revealed that both materials were capable to relax the 63% of the initial stress in less than 10 min at 110( degrees)C. The recyclability of the materials was achieved, and the mechanical and thermomechanical properties of the recycled samples were compared to the virgin ones revealing a great recovery of the initial properties. Finally, Digital Light Processing (DLP) technique was used to print complex structures with high resolution highlighting the great potential of these vitrimeric materials in 3D printing.

Lesser mealworm protein concentrate (LMPC) was conjugated with chlorogenic acid (CA) or tannic acid (TA) using an alkaline method. The impact of polyphenol type and concentration on the physicochemical and structural characteristics, antioxidant, interfacial, and emulsifying properties of the LMPC-polyphenol conjugates were investigated. Under the conditions tested, TA demonstrated higher affinity for LMPC compared to CA. The conjugation of LMPC induced conformational changes as showed by intrinsic fluorescence and FT-MIR raw spectra analysis. The surface hydrophobicity of the conjugates was reduced, leading to increased interfacial tension values for LMPC-TA conjugates without impairment of the emulsifying activity. The antioxidant properties were significantly improved by the conjugation. Flaxseed oil-in-water (O/W) emulsions stabilized by the conjugates and LMPC remained physically stable for 12 days at 50 °C with a notable reduction of secondary oxidation products when conjugates were used. LMPC-TA and LMPC-CA exhibited potential to be used as novel antioxidant emulsifiers in O/W emulsions.

Fortified foods are an important source of dietary vitamin D, since this nutrient occurs naturally in relatively low concentrations in a limited number of foods. Hence, we aimed to investigate the accuracy of the declared vitamin D content of Australian fortified foods. Vitamin D3, 25-hydroxyvitamin D3 (25(OH)D3), vitamin D2 and 25(OH)D2 were measured in 30 fortified food samples (edible oil spreads, malted chocolate drink powders, soy milks and breakfast cereals) using liquid chromatography with triple quadrupole mass spectrometry. The measured vitamin D content ranged from − 54 % to + 190 % of declared values. One product had measured vitamin D content close to the declared value, while 10 of 14 products had vitamin D in excess of that declared. Label information proved an unreliable indicator of measured vitamin D content across all product categories, which may be problematic for those relying on fortified foods as their main source of vitamin D.

The removal of cationic dyes from water has received a great attention of researchers considering their influence on environment and ecosystem. In current work, starch-grafted-poly acrylic acid (St-g-PAA) doped BaO nanostrucutures have been synthesized by co-precipitation approach. The aim of this research was to reduce the harmful methylene blue dye and evaluate the antibacterial activity of St-g-PAA doped BaO. XRD spectra exhibited the tetragonal structure of BaO and no variations occurred upon doping. The optical properties of St-g-PAA doped BaO have been evaluated by UV–Vis spectrophotometer. The existence of a dopant in the product was verified using EDS spectroscopy. TEM revealed the formation of cubic-shaped NPs of BaO and upon the addition of St-g-PAA, a few nanorod-like structures. The higher concentration of St-g-PAA doped BaO exhibit a remarkable reduction of methylene blue in a basic environment. Furthermore, St-g-PAA doped BaO revealed higher antimicrobial efficacy against Staphylococcus aureus in comparison to Escherichia coli. In silico studies were conducted against enoyl-[acylcarrier-protein] reductase (FabI) and beta-lactamase enzyme to evaluate the potential of both St-g-PAA and St-g-PAA doped BaO nanocomposites as their inhibitors and to rationalize their possible mode of action.

Two saccharine-based electrophilic reagents were developed for the direct introduction of SCH2CF3 and SCH2CF2H motifs via a C−S bond forming reaction. Their large-scale preparation and reactivity performance has been carefully examined, enabling access to a series of indoles through open-flask reactions. Sulfone and sulfoxide analogs (S(O)nCH2RF, n=1,2) are also accessible by sequential oxidation reactions. (Figure presented.).

The encapsulation of bluing agents in biodegradable polymeric capsules is an emerging option in laundry detergents sector to substitute formaldehyde-based polymers, because they are non-biodegradable, carcinogenic and toxic. In this work, we present for the first time the successful encapsulation of a blue dye in biodegradable capsules which shell was formed by an alginate hydrogel and a polyethylene glycol network. Different types of capsules were synthesized (addition or not of the diacrylate monomer) and irradiation of the crosslinking solution at different times. Furthermore, a deep characterization of each type of capsules was performed (chemical and morphological characterization, assessment of their mechanical and thermal properties, evaluation of their biodegradability), noting that the incorporation of the diacrylate monomer (PEGDMA) and the two different irradiation times selected substantially affected the final properties of the capsules. The obtained results will serve to comprehend how the dye can be released from the capsules.Copyright © 2023. Published by Elsevier B.V.

BACKGROUND: It has been previously shown that acutely administered insect Alphitobius diaperinus protein increases food intake in rats and modifies the ex vivo enterohormone secretory profile differently than beef or almond proteins. In this study, we aimed to evaluate whether these effects could be maintained for a longer period and determine the underlying mechanisms. RESULTS: We administered two different insect species to rats for 26 days and measured food intake at different time points. Both insect species increased food intake in the first week, but the effect was later lost. Glucagon-like peptide 1 (GLP-1) and ghrelin were measured in plasma and ex vivo, and no chronic effects on their secretion or desensitization were found. Nevertheless, digested A. diaperinus acutely modified GLP-1 and ghrelin secretion ex vivo. CONCLUSION: Our results suggest that increases in food intake could be explained by a local ghrelin reduction acting in the small intestine. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Beads based on a mannuronate(M)-rich alginate (86 % M units) were prepared by adding the polysaccharide solution to a crosslinking bath containing different concentrations (0.5, 2 and 10 wt%) of XCl2 where X = Ca, Cu or Zn. Primarily focus was on Zn, due to its antioxidant, anti-inflammatory and anti-microbial capabilities. The beads were characterized by Field-Emission Scanning Electron Microscopy (FESEM), Fourier-Transform Infra-Red spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), Small-Angle X-ray Scattering (SAXS) and compression tests. The crosslinking agent significantly influenced the properties of the resulting beads. Specifically, Ca-based beads exhibited a smoother surface, while Cu- and Zn-based beads appeared rougher. Interestingly, Zn-based beads displayed a core-shell structure. Young moduli ranged from 3500 and 7000 MPa, with the highest values observed for Zn-beads. SAXS investigation at 0.5 wt% XCl2 suggested increase in the densely packed domains amount in the order: Ca < Cu < Zn. Extended X-ray Absorption Fine Structure (EXAFS) showed that the coordination number was 4.3 ± 0.4 for Cu, and 4.0 ± 0.2 and 1.1 ± 0.1 for Zn in 0.5 wt% XCl2 alginate xerogels, in agreement with reported Density Functional Calculations on Cu2+- and Zn2+-MM complexes. The results from FT-IR, compositional analysis and EXAFS collectively suggested a bridging coordination for these systems.Copyright © 2023. Published by Elsevier B.V.

Even though lignin is very rich in aromatic compounds, it remains the least exploited fraction of biomass due to its recalcitrant nature. Consequently, prevailing efforts to fully unlock its potential are still far from reaching due to the use of harsh conditions and energy-intensive processes which are not environmentally friendly. Herein, a facile approach for coupling acid-catalyzed mechanocatalysis (MC) via ball milling with TiO2 photocatalysis (PC)/Fenton for depolymerization of alkaline lignin was investigated. Mechanocatalysis (MC) involved prior acid impregnation (AI) followed by ball milling. A direct comparison of pretreatments (AI, BM, MC) coupled with oxidation processes was preliminarily undertaken. The untreated lignin (UL) served as the control. MC/PC showed the highest yield of major aromatic products. Vanillin, homovanillic acid, acetovanillone, guaiacol, and vanillic acid were major aromatic building blocks identified and quantified. Further optimization revealed a total monomer yield of 22.77 wt%. SEM and FTIR analysis were done with the latter revealing the existence of pre-oxidation reaction in the BM and MC lignin prior to PC. The proposed synergetic process could offer an advantage over prevailing robust systems used for lignin depolymerization.

Herein, we report a chiral phosphine-triazole ligand for the Ir-catalyzed asymmetric hydrogenation of exocyclic benzofused alkenes. Overcoming previous limitations, the catalytic system is able to successfully hydrogenate exocyclic olefins bearing a benzofused five- and six-membered ring motif (ee's between 92 to 99%). The catalyst tolerates well the presence of several substituents and substitution patterns at both aromatic rings. The absence of a competing isomerization process together with the perfect fit of the olefins in the catalyst chiral pocket are key to surpass the previous limitations in the hydrogenation of both 5- and 6-membered ring benzofused exocyclic olefins.

Vitamin K is vital for normal blood coagulation, and may influence bone, neurological and vascular health. Data on the vitamin K content of Australian foods are limited, preventing estimation of vitamin K intakes in the Australian population. We measured phylloquinone (PK) and menaquinone (MK) -4 to -10 in cheese, yoghurt and meat products (48 composite samples from 288 primary samples) by liquid chromatography with electrospray ionisation-tandem mass spectrometry. At least one K vitamer was found in every sample. The greatest mean (± standard deviation for foods sampled in multiple cities) concentrations of PK (4.9 µg/100 g), MK-4 (58 ± 9 µg/100 g) and MK-9 (8 ± 2 µg/100 g) were found in lamb liver, chicken leg meat and Cheddar cheese, respectively. Cheddar cheese (1.1 ± 0.3 µg/100 g) and cream cheese (1.0 µg/100 g) contained MK-5. MK-8 was found in Cheddar cheese only (4 ± 2 µg/100 g). As the K vitamer profile and concentrations appear to vary considerably by geographical location, Australia needs a vitamin K food composition dataset that is representative of foods consumed in Australia.

The effect of LEDs light on the formation of volatile sulfur compounds (VSCs) and the final sensory quality of white and rosé wines was evaluated. Thus, different commercial wines were exposed for ten days to three types of lights. All wine samples were analyzed throughout the exposure period to determine the usual oenological parameters together with some other chemical characteristics (color evolution; riboflavin, cysteine and methionine photodegradation), VSC amounts and sensory characteristics. The results showed that the wines exposed to ultraviolet light suffered greater degradation of the aromatic precursors, mainly riboflavin, and had higher concentrations of VSCs. Regarding LED lights, these produced minimal degradative effects. So that we can consider this type of light as an alternative to reduce the economic impact that currently occurs due to the photodegradation of bottled wines.

We describe here the conjugate addition of tert-butyllithium to vinyl systems of boronic esters to generate a borata-alkene intermediate, followed by a sequential S(N)2 reaction with alkyl halides, at room temperature. We envisioned this goal through engaged C(sp(3)) chemical entities avoiding metal catalysts, additives, radical initiators or specific irradiation. This reaction guarantees that the new tetrasubstituted carbon formed retains all the C atoms from the three starting materials involved in the assembly.

A set of complex tricyclic compounds containing several functional groups and multiple stereogenic centers has been prepared in only two steps with excellent diastereo- and enantioselectivities. The synthesis takes advantage of the highly versatile and enantioselective Pd-catalyzed allylic substitution of simple cyclic allylic acetates or carbonates to form chiral 1,6-, 1,7- and 1,8-enynes, which are then diastereoselectively transformed to the corresponding cyclopentenone- and cyclobutene-based tricyclic compounds.

The present study aimed to evaluate the metabolism and bioavailability of anthocyanins (ACN) and other phenolics from red-fleshed apple (RFA) and to define the intake biomarkers compared to common white-fleshed apple (WFA). Acute and sustained (6-week) interventions were combined in a randomized, controlled and parallel study with 121 hypercholesterolemic subjects. Another arm consuming ACN-rich infusion from aronia fruit (ARO) provided matched content and profile of ACN. Plasma, urine and faeces samples were analyzed using UPLC-MS/MS. Results showed higher bioavailability of ACN after ARO compared to RFA, showing a clear apple matrix effect. The dihydrochalcone phloretin-2′-O-glucuronide was the most discriminant intake biomarker of both apples. The urinary peonidin-3-O-galactoside was a good biomarker after both ARO and RFA intakes, whereas peonidin-O-arabinoside was reported to be specific from ARO. The elucidation of the phenolic metabolism and the selection of intake biomarkers is a promising approach to relate phenolic compounds and human health.

In this study, MgO-doped CNC-g-PAA hydrogel was synthesized by grafting poly (acrylic acid) (PAA) onto cellulose nanocrystals (CNC) and then doped Magnesium oxide (MgO) using pH 7.0 and 12.0 to obtain an efficient nanocomposite hydrogel for antibacterial and anti-cancer activities. The synthesized nanocomposite hydrogels were evaluated by detailed characterization and confirmed the formation of a well-interconnected porous structure. MgO/CNC-g-PAA (pH = 12.0) exhibited improved bactericidal tendencies towards gram-negative and gram-positive bacteria, which was further investigated by in-silico molecular docking analyses and also examined the reactive oxygen species production by photocatalysis and free radical-scavenging assay. After this, Doxorubicin (DOX), a model anticancer drug, was successfully loaded into nanocomposites (∼79 %) by electrostatic interaction and confirmed pH-triggered based release, which was over 53.7 % in 24 h. Finally, in vitro cytotoxicity-based analysis confirmed the improved antitumor efficacy of nanocomposite hydrogels. These findings revealed that MgO/CNC-g-PAA hydrogels might be prospective carriers for controlled drug delivery.

In present study, control sized cadmium sulphide (CdS) quantum dots (QDs) and cellulose nanocrystals grafted polyvinylpyrrolidone (CNC-g-PVP) doped CdS QDs were synthesized via co-precipitation. The suggested pathway is fruitful in throwing out organic pollutants like methylene blue (MB) from industrial water and bactericidal applications. A series of characterization techniques were used to determine the structural, optical and morphological qualities of prepared samples. The X-ray diffraction (XRD) pattern verified hexagonal structure with no significant change occurring in the spectrum upon doping (2, 4, and 6 %). The UV–vis spectrophotometer describes blueshift in absorption pattern, resulting in an increase in band gap energy (Eg) upon doping. Catalytic activity (CA) against MB in basic and neutral medium demonstrated remarkable results compared with the acidic medium. Furthermore, bactericidal potential of doped sample (6 %) exhibited the significantly higher inhibition zones of 5.25 mm and 4.05 mm against Staphylococcus aureus (S. aureus) or Gram-positive (G+ve) and Escherichia coli (E. coli) or Gram-negative (G-ve), respectively. In silico predictions for these doped QDs were performed against selected enzyme targets (i.e. DNA gyrase and FabI) to unveil the mystery governing these bactericidal activities.

This study shows the monitoring of the physical, chemical and sensorial changes that occur in the sparkling wine along 18 months of aging due to different typology yeast-derived products; dry inactivated yeast from Saccharomyces (Saccharomyces cerevisiae) and non-Saccharomyces (Torulaspora delbrueckii) yeast strains, yeast autolysate, and yeast protein extract tested at two different doses. The addition of 5 g/hL yeast protein extract and inactivated yeast from T. delbrueckii helped to preserve esters in wines with 9 and 18 months of aging on lees. The addition of yeast autolysate achieved greater polysaccharide enrichment and gave rise to sparkling wines with the highest antioxidant activity. Effects on foaming properties were quite different depending on the aging time. Despite this, sparkling wines treated with 10 g/hL of yeast autolysate and Optimum White™ generally exhibited the highest foamability and foam stability. Further experiments with higher doses are needed to observe clear effects on sensory profile.

Food processing contaminants (FPCs) form a wide group of chemicals that are generated during different cooking practices. This study was aimed at determining the levels of a number of FPCs (i.e., acrylamide, furans, monochloropropanediols (MCPDs) and glycidyl esters (GEs)) in foodstuffs purchased in Catalonia (Spain), and assessing the human exposure for different population groups. The dietary intake of acrylamide for the adult population was estimated in 2.91 ?g/day, while that of furan, 2-methylfurans and 3-methylfurans was 4.32, 7.35 and 0.439 ?g/day, respectively. Finally, the exposure to 3-MCPD, 2-MCPD, 3-MCPD esters, 2-MCPD esters and GEs through food consumption was estimated in 0.657, 0.529, 10.7, 5.15 and 8.81 ?g/day, respectively. The risk assessment showed that there is a health concern for developing neoplastic effects derived from the intake of acrylamide for all the population groups. In addition, toddlers and infants would exceed the threshold values of 3-MCDP and GEs. The global analysis of these results indicates that a special attention should be paid to the youngest population groups in Catalonia, reinforcing the need of conducting periodical monitoring studies and developing policy measures, especially focused on foodstuffs highly consumed by toddlers, infants and children. © 2021 The Author(s)

Australia needs accurate vitamin D food composition data to support public health initiatives. Previously, limitations in analytical methodology have precluded development of a comprehensive database. We used liquid chromatography with triple quadrupole mass spectrometry (LC-QQQ) to analyse 149 composite samples representing 98 foods (primary samples n = 896) in duplicate for vitamin D3, 25-hydroxyvitamin D3 (25(OH)D3), vitamin D2, 25(OH)D2. The greatest concentrations of vitamin D3 were found in canned salmon and a malted chocolate drink powder (fortified); chicken eggs and chicken leg meat contained the most 25(OH)D3. Margarine (fortified) and chocolate contained the greatest concentrations of vitamin D2, with smaller amounts found in various meat products. 25(OH)D2 was detected in various foods, including meats, and was quantitated in lamb liver. These data advance knowledge of dietary vitamin D in Australia and highlight the importance of analysis of these four forms of vitamin D to accurately represent the vitamin D content of food.

The existence of defects in perovskite films is a major obstacle that prevents perovskite solar cells (PSCs) from high efficiency and long-term stability. A variety of additives have been introduced into perovskite films for reducing the number of defects. Lewis base-based additive engineering has been considered as an effective way to eliminate defects, especially the defects caused by the uncoordinated Pb2+. In this work, for the first time, a bilateral cyano molecule (succinonitrile, SN) which is a commonly used plasticizer in solid electrolyte of solid-state lithium batteries was selected as an additive to modify organic–inorganic hybrid perovskite films in PSCs. SN is featured with two cyano groups (–C≡N) distributing at both terminals of the carbon chain, providing two cross-linking points to interact with perovskites crystals via coordinating with uncoordinated Pb2+ and forming hydrogen bonds with –NH2 groups in perovskite. It was found that the addition of SN into perovskite precursor solution could effectively reduce defects, particularly inhabit the appearance of Pb0 and thus suppress trap-assisted nonradiative charge carrier recombination. As a result, the efficiency of CH3NH3PbI3(Cl) (MAPbI3(Cl))-based PSCs was improved from 18.4% to 20.3% with enhanced long-term stability at N2 and humid air atmosphere. This work provides a facile and effective strategy to enhance the PCE and stability of PSCs simultaneously, facilitating the commercialization of PSCs.

Hydrogen is considered an attractive alternative to fossil fuels, but only a small amount of it is produced from renewable energy, making it not such a clean energy carrier after all. Producing hydrogen through water electrolysis is promising, but using a cost-effective and high-performing catalyst that has long-term stability is still a challenge. This study exploits, for the first time, the potential of zinc oxide nanoparticles with diverse morphologies as catalysts for the electrocatalytic production of hydrogen from water. The morphology of the nanoparticles (wires, cuboids, spheres) was easily regulated by changing the concentration of sodium hydroxide, used as the shape controlling agent, during the synthesis. The spherical morphology exhibited the highest electrocatalytic activity at the lowest potential voltage. These spherical nanoparticles had the highest number of oxygen vacancies and lowest particle size compared to the other two morphologies, features directly linked to high catalytic activity. However, the nanowires were much more stable with repeated scans. Density-functional theory showed that the presence of oxygen vacancies in all three morphologies led to diminished band gaps, which is of catalytic interest.

© 2020 Elsevier Ltd In the present study, potential associations between dietary phenolic compounds (PCs), gut microbiota composition and targeted faecal metabolites were identified in a cross-sectional study including grade 1 hypertensive (HT) and normotensive (NT) subjects. We performed comprehensive quantification of PC intake, together with 16S rRNA gene sequencing of the gut microbiota, and faecal and plasma short-chain fatty acids (SCFAs) determination. The results showed multiple-way relationships between PCs from several plant-based foods and 25 bacterial taxa previously defined as discriminant biomarkers among groups. Remarkably, coffee PCs were positively associated with systolic and diastolic blood pressure, faecal SCFAs, Bacteroides plebeius and Bacteroides coprocola in HT and negatively associated with Faecalibacterium prausnitzii and Christensenellaceae R-7 in NT. Olive fruit PCs were positively associated with Ruminococcaceae UCG-010, Christensenellaceae R-7 and plasma SCFAs in NT. These interplays with discriminant bacterial taxa in HT and NT subjects highlight the potential role of specific PCs as gut microbiome modulators in either the pathogenesis or prevention of hypertension.

Dual-curing is a processing technology based in the combination of two polymerization processes and the proper selection of the formulation. This methodology allows the preparation of intermediate materials with tailored characteristics, which can be viscous-liquids or rubbery solids according to their application. Once applied, the second stage is performed leading to a high crosslinked network. Usually, different monomers are involved, and unreacted monomer are still present in the intermediate material. This monomer experiments polymerization during the second step, but it can drip or be exuded during storage. In the present work, a commercial monomer, glycidyl methacrylate has been selected, because of the presence in the same molecule of an epoxide group, which can react with amines in the first stage of the dual-curing, and a methacrylate group that can be thermally or photochemically homopolymerized to complete the curing process. Diglycidylether of bisphenol A has been added to obtain a gelled intermediate material. The evolution of both curing steps has been studied by DSC and FTIR. The stability of the intermediate material has been confirmed and the characteristics of intermediate and final material have been evaluated by TGA and DMTA.

© 2020 Cancer is a major health issue concerning to all of us. Current treatment options are still limited due to not-selective action. Encapsulation is contemplated as an innovative approach to address systemic toxicity and tumor resistance caused by traditional therapies, while increasing encapsulated compounds bioavailability. The coating material of capsules strongly determines the success of the system. Since alginate has been proved non-toxic, biocompatible and biodegradable, it is considered a potential vehicle for therapeutic factors encapsulation. Besides, it has the particular ability to form hydrogels, which hold a high-water content and greatly resemble to natural soft tissues. The present review exposes the state-of-the-art and the most sophisticated alginate-based systems for cancer therapy and research. It begins with an overview of alginate hydrogels and the qualities that make them especially suitable for biomedical applications. In the following section, the application of alginate hydrogels as pioneering strategies for cancer treatment is described. Several examples of alginate-based delivery systems of therapeutic drugs, proteins and nucleic acids are provided. Significant emphasis is placed in both oral delivery systems and colorectal cancer therapy. Moreover, the role of alginate 3-D scaffolds for both cell culture and delivery is explained. Lastly, other applications of alginate-based hydrogels such as tumor biomarkers immunosensing and fluorescent surgical marker are included.

© 2020 Elsevier Inc. The accumulation and potential health risks of eight trace elements (Cu, Cd, Cr, Mn, Zn, Pb, Hg and As) were analyzed in the commercially important crayfish and oriental river prawn species from the Zhenjiang City, Jiangsu Province, China. The accumulation sequence of elements in different tissues were as gill > walking leg > muscle. Among the analyzed elements, majority of the elements were accumulated in the gill tissue, while Hg was concentrated in abdominal muscle and Zn in walking leg tissues. The elements Zn (95.9 μg g−1) and Cd (0.02 μg g−1) were the most and the least accumulated elements in the abdominal muscle tissue. The calculated estimated daily intake (EDI) and hazard indices (HI) of the analyzed elements in the tissue organs of Procambarus clarkii and Macrobrachium nipponense species were lower than the Chinese Food Health Criterion and international guideline values and results in no acute toxicities and thus, safe for human consumption. This study also suggests that Procambarus clarkii species can be used as an effective bio-indicator organism for examining the toxic heavy metals in the freshwater ecosystems.

© 2020 by Japan Oil Chemists’ Society. The surface charge/surface potential of the air/water interface plays a key role in many natural and industrial processes. Since the first decade of the 20th century, there are many theoretical proposals to describe the surface charge in the presence of different moieties. However, a complete and consistent description of the interfacial layer remains elusive. More recently, the theoretical frameworks and experimental data get complementary support from the simulation at a molecular level. This paper reviews the recent developments from the theoretical, experimental and simulation aspects. The combined results indicated that the interaction between hydration shells of adsorbed ions and the H-bonds network of surface water plays a critical role in the ionic adsorption. The factor should be incorporated into the conventional theories to correctly predict the ion distribution near the air/water surface.

© 2020 Society of Chemical Industry BACKGROUND: The use of healthy olives and their good management along the production process are necessary to obtain the best quality virgin olive oils. One parameter related to the health of the olives is the content of fatty acid alkyl esters. Because these come from the esterification of C16 and C18 free fatty acids with short chain alcohols, the control of methanol, ethanol and acetaldehyde (precursor of ethanol) and their origin (endogenous or from fermentation) is essential. The present study reports the endogenous amount of these compounds in some of the main Spanish olive varieties. For their analyses, headspace solid phase micro-extraction was applied and, to ensure quantitation reliability, the matrix-matched technique was used to build the calibration lines. RESULTS: For healthy and mature olives, the contents of ethanol and methanol are much higher and vary within a wider range than those corresponding to acetaldehyde. Because olives were not directly analyzed but previously homogenized, there was no correlation between the olive size parameters and the contents of the compounds investigated. However, these contents are characteristic of each variety. When comparing healthy and unhealthy olives, significant differences were only observed for ethanol contents. CONCLUSION: Higher contents of short alcohols are not only the result of an unhealthy or poor state of the fruits, but also the variety. Therefore, because these alcohols are precursors of fatty acid alkyl esters, the maximum permissible content of the latter should not be set at a single value for all olive varieties. © 2020 Society of Chemical Industry.

© 2020 Elsevier B.V. Networked poly(thiourethane) materials with Tgs around 130 °C, derived from two aliphatic isocyanates (isophorone diisocyanate, IPDI and 4,4′-methylene bis(cyclohexyl isocyanate), HMDI) and one aromatic diisocyanate (toluene-2,4-diisocyanate, TDI) have been prepared with the same trithiol as comonomer (trimethylol propane tris(3-mercaptopropionate), S3) in stoichiometric proportions in the presence of dibutyltin dilaurate (DBTDL) as the catalyst. The higher reactivity of TDI allowed the preparation of this material in absence of catalyst. The evolution of the curing process has been followed by FTIR. Thermomechanical studies have been performed to determine their viscoelastic properties and their vitrimeric behaviour. The materials were able to reach a complete relaxation stress state thanks to the exchange process of the thiourethane moiety. Among them, TDI derived material experimented the fastest relaxation. The materials were also characterized by thermogravimetry and tensile tests. The recycled materials obtained by grinding the original thermosets and hot-pressing the powder have been fully characterized by mechanical, thermomechanical and FTIR studies, which allowed to confirm their recyclability without appreciable changes in the network structure. The presence of DBTDL in the materials has been proved to be necessary to reach a good recyclability.

© 2020 Elsevier Ltd Melatonin and serotonin are bioactive compounds present in foods and beverages and related to neuroprotection and anti-angiogenesis, among other activities. They have been described in wines and the role of yeast in their formation is clear. Thus, this study evaluates the content of these bioactives and other related indolic compounds in beer. For this purpose, commercial beers were analyzed by a validated UHPLC-HRMS method and sample treatment optimized due to the low concentrations expected. Moreover, a wort was fermented with different commercial beer yeast (Abbaye, Diamond, SafAle, SafLager) in order to monitor the formation of these bioactives during the elaboration process. Results show that indolic compounds such as N-acetylserotonin and 3-indoleacetic acid are produced during the alcoholic fermentation of wort. Moreover, the occurrence of four indolic compounds (5-hydroxytryptophan, N-acetylserotonin, 3-indoleacetic acid, L-tryptophan ethyl ester) in commercial beers is reported for the first time.

The interaction between stomach porcine mucin and 3 oenological tannins (extract of ellagitannins from oak, extract of gallotannins from gall nuts and extract of proanthocyanidins from grape seeds) was measured by Surface Plasmon Resonance (SPR). These tannins were analysed and their astringency was determined using the Astringency Index method and by tasting. The interaction constants were determined using a Biacore SPR device (1:1 Langmuir binding model). The results indicate that the ellagitannins are more astringent than gallotannins and those, in turn, are more astringent than seed proanthocyanidins if the richness of the commercial extracts is considered. The astringency index of these tannins had high correlation and regression coefficients with their kinetic and thermodynamic dissociation constants. This data support a hypothesis that astringency depends not only on the thermodynamic tendency to form the complex between tannins and salivary proteins but also probably on the time required to dissociate the complex.

© 2019 Elsevier B.V. Trimetallic Co-Ni-Cu catalyst from perovskite precursor was prepared by co-precipitation method and then examined for its ability to form higher alcohols from syngas. A superior C2+OH yield of 142.1 mg·gcat.−1·h−1 was achieved at 315 °C, H2/CO = 2, P = 3.0 MPa and GHSV of 10,995 ml·gcat−1·h−1, which was almost two times higher than that obtained with monometallic Co and bimetallic Co[sbnd]Ni perovskite catalysts. The addition of Cu alters the electronic interactions with the Co and Ni species, thereby promoting the reduction of perovskite catalysts and forming Co-Ni-Cu alloy after reduction. It was found that the substitution of Cu facilitated the formation of Co2C species during the reaction. Both Co-Ni-Cu alloy and Co2C species were observed in the spent catalyst, suggesting that the formation of Co-Ni-Cu alloy and Co-Co2C interface play key roles in the improvement of higher alcohol formation.

© 2018 Elsevier Ltd Fluorescent polarity probes are usually based on intramolecular charge transfer excited states of selected dyes, the behavior of which in different solvents is traditionally rationalized by the well-known Lippert-Mataga treatment of the “general solvents effect”. Less often transition metal coordination complexes are used as luminescent probes, even though the spectroscopic properties of these dyes are usually dependent on the environment. This is the case of Ru(II) polypyridyls, which are good candidates to develop robust sensitive polarity probes because of their lowest-lying metal-to-ligand charge transfer triplet emissive state, provided their chelating ligands structure is judiciously tuned. The aim of this work has been to design a computational strategy to forecast the behavior of polarity-sensitive Ru(II) complexes without the need to prepare a large set of candidates. In particular, we have analysed a number of complexes derived from [Ru(bpy)3]2+ by introducing different pairs of substituents in the 4,4′ positions of one of the three equivalent 2,2′-bipyridine (bpy) moieties. In this way, we have investigated if a direct relationship may be established between the electronic features of the substituent and the Stokes shift sensitivity to the solvent polarity. Our computational data satisfactorily agree with our experimental results, but they demonstrate that only by explicitly performing the calculation of the Stokes shift in different media for each candidate, it is possible to select the best Ru(II) dyes to be used as polarity probes.

The interaction between stomach porcine mucin and 3 oenological tannins (extract of ellagitannins from oak, extract of gallotannins from gall nuts and extract of proanthocyanidins from grape seeds) was measured by Surface Plasmon Resonance (SPR). These tannins were analysed and their astringency was determined using the Astringency Index method and by tasting. The interaction constants were determined using a Biacore SPR device (1:1 Langmuir binding model). The results indicate that the ellagitannins are more astringent than gallotannins and those, in turn, are more astringent than seed proanthocyanidins if the richness of the commercial extracts is considered. The astringency index of these tannins had high correlation and regression coefficients with their kinetic and thermodynamic dissociation constants. This data support a hypothesis that astringency depends not only on the thermodynamic tendency to form the complex between tannins and salivary proteins but also probably on the time required to dissociate the complex.

© 2018 Elsevier B.V. Graphene like-TiO2nanocomposites (rGO-TiO2) are prepared via hydrothermal route by following different synthetic protocols. The as-prepared nanostructured materials exhibit higher photocatalytic activity than bare TiO2in the treatment of synthetic produced water containing high salinity levels and different compositions of recalcitrant dissolved organic matter. The effect of the preparation method on the physico-chemical properties is assessed by performing a wide characterization combining different analyses, such as nitrogen physic-adsorption (BET), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), UV-VIS Diffuse Reflectance Spectroscopy (DRUV) and Electron Paramagnetic Resonance (EPR). The effect of several operative variables (i.e., TiO2/rGO weight ratios, and addition of hydrogen peroxide) on the photocatalytic activity is also critically evaluated. The highest photocatalytic activity is obtained for a rGO/TiO2weight ratio of about 10%, for which a good compromise between uniformity of dispersion of the TiO2particles on the rGO layers and covering degree of the titania photoactive surface is achieved. This study can contribute to open new perspectives in the design of high performance graphene like-based TiO2photocatalysts for removing hydrophobic bio-recalcitrant pollutants from saline water.

Anthocyanins (ACNs) are promising health-enhancing phenolic compounds. We focus on ACN animal tissue bioavailability to provide an evidentiary link between tissue ACNs and their associated health properties. We performed a systematic review of electronic libraries; 279 results were retrieved, and 13 publications met inclusion criteria. Extracted information included animal model employed, administration route, doses, analysis method, and ACN concentration values in tissues. Total ACN concentrations were detected in mice kidney (2.17 × 105 pmol/g), liver (1.73 × 105 pmol/g), heart (3.6 × 103 pmol/g), and lung (1.16 × 105 pmol/g); and in pig brain (6.08 × 103 pmol/g). ACNs showed a predominance of parent ACNs in long-term experiments versus an ACN metabolite predominance in short-term experiments. ACNs detected in animal tissues, such as cyanidin-3-glucoside, suggest it may have an important role in human health. This information could be useful to determine proper ACN-intake biomarkers in biological samples in futures studies.

Developing new distillation strategies can help the spirits industry to improve quality, safety and process efficiency. Batch stills equipped with a packed column and an internal partial condenser are an innovative experimental system, allowing a fast and flexible management of the rectification. In this study, the impact of four factors (heart-cut volume, head-cut volume, pH and cooling flow rate of the internal partial condenser during the head-cut fraction) on 18 major volatile compounds of Muscat spirits was optimized using response surface methodology and desirability function approaches. Results have shown that high rectification at the beginning of the heart-cut enhances the overall positive aroma compounds of the product, reducing off-flavor compounds. In contrast, optimum levels of heart-cut volume, head-cut volume and pH factors varied depending on the process goal. Finally, three optimal operational conditions (head off-flavors reduction, flowery terpenic enhancement and fruity ester enhancement) were evaluated by chemical and sensory analysis.

© 2018 Elsevier B.V. Graphene like-TiO2nanocomposites (rGO-TiO2) are prepared via hydrothermal route by following different synthetic protocols. The as-prepared nanostructured materials exhibit higher photocatalytic activity than bare TiO2in the treatment of synthetic produced water containing high salinity levels and different compositions of recalcitrant dissolved organic matter. The effect of the preparation method on the physico-chemical properties is assessed by performing a wide characterization combining different analyses, such as nitrogen physic-adsorption (BET), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), UV-VIS Diffuse Reflectance Spectroscopy (DRUV) and Electron Paramagnetic Resonance (EPR). The effect of several operative variables (i.e., TiO2/rGO weight ratios, and addition of hydrogen peroxide) on the photocatalytic activity is also critically evaluated. The highest photocatalytic activity is obtained for a rGO/TiO2weight ratio of about 10%, for which a good compromise between uniformity of dispersion of the TiO2particles on the rGO layers and covering degree of the titania photoactive surface is achieved. This study can contribute to open new perspectives in the design of high performance graphene like-based TiO2photocatalysts for removing hydrophobic bio-recalcitrant pollutants from saline water.

© 2018 Elsevier Ltd A new biosensor for monitoring glucose levels in beverages is presented. The measurements are performed using potentiometric detection. Working electrodes are made using platinised paper as support and a biocompatible polymeric membrane made of a mixture of polyvinyl alcohol and chitosan containing glucose oxidase as the recognition layer. The system is based on the detection of the hydrogen peroxide generated by an enzymatic reaction performed in a highly sensitive, selective and simple way. The biosensors display suitable analytical performance (sensitivity −119.6 ± 6.4 mV/dec in the 0.03–1.0 mM range with a limit of detection of 0.02 mM). Determination of glucose in commercial orange juices is presented. These results were validated against conventional standard methods, showing good accuracy and fast analytical response. The methodology presented herein does not require complex samples treatment, offering an alternative to conventional methods, particularly for determinations performed with minimal expertise and without a laboratory infrastructure.

The enteroendocrine system coordinates gastrointestinal (GI) tract functionality and the whole organism. However, the scarcity of enteroendocrine cells and their scattered distribution make them difficult to study. Here, we glued segments of the GI wall of pigs to a silicon tube, keeping the apical and the basolateral sides separate. The fact that there was less than 1% of 70-kDa fluorescein isothiocyanate (FITC)-dextran on the basolateral side proved that the gluing was efficient. Since the lactate dehydrogenase leakage at basolateral side was lower than 0.1% (1.40 ± 0.17 nKatals) it proved that the tissue was viable. The intestinal barrier function was maintained as it is in segments mounted in Ussing chambers (the amount of Lucifer Yellow crossing it, was similar between them; respectively, % LY, 0.48 ± 0.13; 0.52 ± 0.09; p > 0.05). Finally, apical treatments with two different extract produced differential basolateral enterohormone secretions (basolateral PYY secretion vs control; animal extract, 0.35 ± 0.16; plant extract, 2.5 ± 0.74; p < 0.05). In conclusion, we report an ex vivo system called "Ap-to-Bas" for assaying vectorial transepithelial processes that makes it possible to work with several samples at the same time. It is an optimal device for enterohormone studies in the intestine.

There is no any doubt about the importance of food fraud control, as it has implications in food safety and in consumer health. Focusing on fruit beverages, some types of adulterations have been detected more frequently, such as substitution with less expensive fruits. A methodology based on attenuated total reflectance Fourier-transform mid-infrared spectroscopy (ATR-FTIR) and multivariate classification was applied to detect whether grape nectars were adulterated by substitution with apple juice or cashew juice. A total of 126 samples were obtained and analyzed. Two strategies were proposed: one-class and multiclass approaches. Soft independent modeling of class analogy (SIMCA), partial least squares discriminant analysis (PLS-DA) and partial least squares density modeling (PLS-DM) were used to build the models. Among them, PLS-DA presented the best performance with a sensitivity and specificity of nearly 100%. The multiclass strategy was preferred if the adulterants to be studied are known because it provides additional information

Moroccan and French honeys from different geographical areas were classified and characterized by applying a voltammetric electronic tongue (VE-tongue) coupled to analytical methods. The studied parameters include color intensity, free lactonic and total acidity, proteins, phenols, hydroxymethylfurfural content (HMF), sucrose, reducing and total sugars. The geographical classification of different honeys was developed through three-pattern recognition techniques: principal component analysis (PCA), support vector machines (SVMs) and hierarchical cluster analysis (HCA). Honey characterization was achieved by partial least squares modeling (PLS). All the PLS models developed were able to accurately estimate the correct values of the parameters analyzed using as input the voltammetric experimental data (i.e. r > 0.9). This confirms the potential ability of the VE-tongue for performing a rapid characterization of honeys via PLS in which an uncomplicated, cost-effective sample preparation process that does not require the use of additional chemicals is implemented.

© 2018 Elsevier Ltd ‘Calçots’ the immature floral stems of second-year onion resprouts, are an economically important traditional crop in Catalonia (Spain). Classical approaches to evaluating the chemical properties of ‘calçots’ are time consuming and expensive; near-infrared spectroscopy (NIRS) may be faster and cheaper. We used NIRS to develop partial least square (PLS) models to predict dry matter, soluble solid content, titratable acidity, and ash content in cooked ‘calçots’. To guarantee the robustness of the models, calibration samples were grown and analyzed in a first season (2014–15) and validation samples in a second season (2015–16). NIRS on puree spectra estimated dry matter and soluble solid content with excellent accuracy (R2pred = 0.953, 0.985 and RPD = 4.571, 8.068, respectively). However, good estimation of titratable acidity and ash content required using ground dried puree spectra (R2pred = 0.852, 0.820 and RPD = 2.590, 1.987, respectively). NIRS can be a helpful tool for ‘calçots’ breeding and quality control.

BACKGROUND Fungicide residues on fruit may adversely affect yeast during cider fermentation, leading to sluggish or stuck fermentation or the production of hydrogen sulfide (H₂S), which is an undesirable aroma compound. This phenomenon has been studied in grape fermentation but not in apple fermentation. Low nitrogen availability, which is characteristic of apples, may further exacerbate the effects of fungicides on yeast during fermentation. The present study explored the effects of three fungicides: elemental sulfur (S⁰) (known to result in increased H₂S in wine); fenbuconazole (used in orchards but not vineyards); and fludioxonil (used in post-harvest storage of apples). RESULTS Only S⁰ led to increased H2S production. Fenbuconazole (≥0.2 mg L⁻¹) resulted in a decreased fermentation rate and increased residual sugar. An interactive effect of yeast assimilable nitrogen (YAN) concentration and fenbuconazole was observed such that increasing the YAN concentration alleviated the negative effects of fenbuconazole on fermentation kinetics. CONCLUSION Cidermakers should be aware that residual fenbuconazole (as low as 0.2 mg L⁻¹) in apple juice may lead to stuck fermentation, especially when the YAN concentration is below 250 mg L⁻¹. These results indicate that fermentation problems attributed to low YAN may be caused or exacerbated by additional factors such as fungicide residues, which have a greater impact on fermentation performance under low YAN conditions.

BACKGROUND Fungicide residues on fruit may adversely affect yeast during cider fermentation, leading to sluggish or stuck fermentation or the production of hydrogen sulfide (H₂S), which is an undesirable aroma compound. This phenomenon has been studied in grape fermentation but not in apple fermentation. Low nitrogen availability, which is characteristic of apples, may further exacerbate the effects of fungicides on yeast during fermentation. The present study explored the effects of three fungicides: elemental sulfur (S⁰) (known to result in increased H₂S in wine); fenbuconazole (used in orchards but not vineyards); and fludioxonil (used in post-harvest storage of apples). RESULTS Only S⁰ led to increased H2S production. Fenbuconazole (≥0.2 mg L⁻¹) resulted in a decreased fermentation rate and increased residual sugar. An interactive effect of yeast assimilable nitrogen (YAN) concentration and fenbuconazole was observed such that increasing the YAN concentration alleviated the negative effects of fenbuconazole on fermentation kinetics. CONCLUSION Cidermakers should be aware that residual fenbuconazole (as low as 0.2 mg L⁻¹) in apple juice may lead to stuck fermentation, especially when the YAN concentration is below 250 mg L⁻¹. These results indicate that fermentation problems attributed to low YAN may be caused or exacerbated by additional factors such as fungicide residues, which have a greater impact on fermentation performance under low YAN conditions.

We report helium adsorption capacities and the true specific impenetrable solid volumes of a clinoptilolite-rich Escott zeolite from Werris Creek (Australia), synthetic 3A and 4A zeolites, and carbon molecular sieve 3K-172 measured by a gravimetric method at pressures of (300–3500) kPa and temperatures in the range of (303–343) K. Our helium adsorption procedure extends the previous works by Gumma and Talu [1] to determine the impenetrable solid volume of the adsorbent, which in standard helium pycnometry is determined under the assumption that helium does not adsorb at room temperature. Our results confirm helium adsorption on these solids is small, but not zero: equilibrium helium adsorption capacities measured at 3500 kPa and 303 K were 0.067 mmol/g on Escott, 0.085 mmol/g on 3A, 0.096 mmol/g on 4A and 0.089 mmol/g on 3K-172. The specific solid volumes determined by the Gumma and Talu method were 10–15% larger than the specific solid volumes measured by standard helium pycnometry, and this error can result in uncertainties of 2.6–28% in the equilibrium adsorption capacities of CO2 and N2 measured at high pressures. The uncertainties were largest for N2 on the Escott zeolite, which had the lowest equilibrium adsorption capacity for N2. These results support the need to consider helium adsorption in the characterisation of adsorbents with narrow pore sizes, especially for adsorption processes that involve helium separations at low temperatures and/or high pressures.

BACKGROUND Fungicide residues on fruit may adversely affect yeast during cider fermentation, leading to sluggish or stuck fermentation or the production of hydrogen sulfide (H₂S), which is an undesirable aroma compound. This phenomenon has been studied in grape fermentation but not in apple fermentation. Low nitrogen availability, which is characteristic of apples, may further exacerbate the effects of fungicides on yeast during fermentation. The present study explored the effects of three fungicides: elemental sulfur (S⁰) (known to result in increased H₂S in wine); fenbuconazole (used in orchards but not vineyards); and fludioxonil (used in post-harvest storage of apples). RESULTS Only S⁰ led to increased H2S production. Fenbuconazole (≥0.2 mg L⁻¹) resulted in a decreased fermentation rate and increased residual sugar. An interactive effect of yeast assimilable nitrogen (YAN) concentration and fenbuconazole was observed such that increasing the YAN concentration alleviated the negative effects of fenbuconazole on fermentation kinetics. CONCLUSION Cidermakers should be aware that residual fenbuconazole (as low as 0.2 mg L⁻¹) in apple juice may lead to stuck fermentation, especially when the YAN concentration is below 250 mg L⁻¹. These results indicate that fermentation problems attributed to low YAN may be caused or exacerbated by additional factors such as fungicide residues, which have a greater impact on fermentation performance under low YAN conditions.