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This work describes the development of temperature-induced dispersive solid phase extraction (TI-DSPE) for the isolation and measurement of cobalt in food and water samples. The concentration of the preconcentrated cobalt ions was determined using flame atomic absorption spectrometry (FAAS). In TI-DSPE, the dispersion of the sorbent occurs by varying the temperature. The cobalt was complexed with 1-nitroso-2-naphthol and extracted with finely dispersed benzoic acid particles at 60 °C. The extraction efficiencies parameters were assessed and optimized, such as the mass of benzoic acid, dissolution temperature, solution pH, centrifugation conditions, and ionic strength. In the optimum conditions, the analytical curve was linear from 2.0 to 150.0 µg L−1, the limits of detection and quantification were 0.55 and 1.83 µg L−1 respectively, and the preconcentration factor was 50. Ten repeated measurements at 50.0 µg L−1 yielded a relative standard deviation (RSD) of 2.6% (n = 10). High extraction recoveries (96.5–102.5%) were obtained from the analysis of real samples. The validity of the developed procedure was confirmed by analyses of certified reference materials (QC-1187 and SPS-SW2). The results demonstrated that the developed method was simple, efficient, and cost-effective. [ABSTRACT FROM AUTHOR]

This study aimed to optimize a liposomal formulation to enhance the stability of a phenolic-rich extract from green walnut husk. Liposomes were prepared using varying concentrations of phosphatidylcholine (0.15–2% w/v), extract (0–1.3% v/v), and sodium laurate (0–0.2% w/v) via ethanol injection and sonication. Characterization included visual appearance, particle size, polydispersity index, surface charge, encapsulation efficiency, and morphology. Stable liposomes were achieved at 0.15% and 0.3% w/v phosphatidylcholine, although with low encapsulation efficiency (<40%). The addition of 0.2% (w/v) sodium laurate improved the stability, especially at higher phosphatidylcholine concentrations, enhancing the electrostatic repulsion. Optimal concentrations of 2% w/v phosphatidylcholine, 0.2% w/v sodium laurate, and 0.6% v/v extract were determined. The liposomes exhibited a spherical unilamellar morphology with a size of 97.5 ± 0.9 nm and a negative surface charge of –39.8 ± 0.9 mV. These nanoliposomes showed 79.7 ± 0.7% encapsulation efficiency and remained stable under pH, temperature, ionic strength, and storage time variations. Overall, the liposomes proved effective in preserving the natural phenolics of walnut husks under challenging environmental conditions. [ABSTRACT FROM AUTHOR]

This work dealt with the extractive performance and behaviors of new three Schiff base amphiphiles ligands derived from 3-mercapto-1,2,4-triazole and different alkyl chains for recovery of nickel(II) from concentrated saline chloride medium (1 M ± 0.01) at 30 ± 1 °C. The chloroform has been used as solvent for research purposes only. The effects of the main experimental parameters such as extraction time, pH, extractant concentration and ionic strength of the aqueous medium on the extraction process of nickel(II) with amphiphilic Schiff bases (ASBn) were studied and compared. The analysis of extraction data revealed that the synthesized Schiff bases exhibit a better and faster extractability than many extractants reported in the literature. The extraction constants, log Kex, of these chelating extractants increased with an increase in the alkyl chain. A good recovery (E = 75–100%± 0.05) of nickel was obtained with amphiphilic Schiff bases. The hydrophobic Schiff base amphiphile (ASB18) was the most effective extractant for nickel ions from chloride solutions in the acidic pH range (2.41 − 2.90 ± 0.02). Ni(II) was readily extracted by ASB18 in 5 min. Extracted complexes NiL2 into chloroform phase were ascertained by slope analysis method for all extractants. The extraction mechanism of nickel(II) have been finally suggested. The results obtained are promising and can find practical applications such as for recovering of Ni(II) from Ni-MH battery wastes and electroplating industries effluents. However, in view of the acute toxicity of the solvent chloroform, implementation of this process in large-scale nickel processing strategies needs to be thoroughly evaluated from an environmental perspective. [ABSTRACT FROM AUTHOR]

Atmospheric aerosol particles can impact the optical depth of mixed-phase clouds through heterogeneous ice nucleation. Ice nucleating particles (INP) are therefore important contributors to global and local climate but remain under-parameterized in climate models, partially due to the complex interaction between composition and processing conditions. In this article, we study the ice nucleation (IN) activity of montmorillonite bentonite clay which is a common model dust INP, utilizing a 150-well microfluidic device. Refreezing tests are carried out for solutions across a range of salinity and pH to determine the impact of composition and processing on droplet freezing behavior, with and without an intermediate relative humidity (RH) cycling step. It is found that freezing order deviation dramatically increases after droplets undergo RH cycling, and the potential influence on IN activity of delamination of clay when subjected to changing RH conditions is discussed. Freezing order deviation decreases with increasing solution ionic strength, a trend linked to the delamination behavior of bentonite clays, and an overall decrease in IN activity at low pH is observed, possibly due in part to pH-dependent changes in clay aggregate size distribution. The authors conclude that pH changes and RH processing, such as those which naturally occur in the atmosphere, have a marked impact on the IN activity of clay-containing aerosol droplets. Copyright © 2024 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

In order to improve the functionality of cellulosic materials research and development of high performance soluble materials. Therefore, the Fe3O4/CMS composite membrane was prepared by using carboxymethyl salix powder (CMS) and Fe3O4 as raw materials, 1-propenyl-3-methylimidazolium chloride and dimethyl sulfoxide as dissolution system. The effects of swelling time, swelling temperature, pH and ionic strength on the swelling performance of Fe3O4/CMS composite membranes and the swelling kinetics of the composite membranes were studied. The structure of the composite membrane was characterized by SEM, FT-IR, XRD and TG. The results showed that the swelling degree reached 5.54 g·g−1, when the swelling time was 45 min, the swelling temperature was 65°C, the pH was 5 and the ionic strength was 0.08 mol·L−1. The initial phase of dissolution of the composite membrane fits well with the Fickian diffusion model, and the whole dissolution process belongs to the Schott model, indicating that the main role of the dissolution process is the diffusion of water molecules, while the composite membrane can be preserved for a long time at high temperature, which provides sustainability for the composite membrane. The characterization results showed that the surface of Fe3O4/CMS composite film was rough with small grooves. The O-H effect was enhanced and the Fe-O absorption peak appeared at 600 cm−1, indicating that Fe3O4 had been successfully loaded onto the cellulose membrane. The Fe3O4/CMS composite membrane belonged to cellulose type II structure, meanwhile, the composite membrane had good thermal stability. [ABSTRACT FROM AUTHOR]

Emulsified meat products are key deep-processing products due to unique flavor and high nutritional value. Myosin dissolves, and protein aggregation and heat-induced gelation occur after myosin unfolds and hydrophobic groups are exposed. Myosin could form interfacial protein membranes and wrap fat globules. Emulsified fat globules may be filled in heat-induced gel networks. Therefore, this review intends to discuss the influences of heat-induced gelation and interfacial adsorption behavior on oil and water retention. Firstly, the mechanism of heat-induced gelation was clarified from the perspective of protein conformation and micro-structure. Secondly, the mechanism of emulsification stability and its factors affecting interfacial adsorption were demonstrated as well as limitations and challenges. Finally, the structure characteristics and application of multi-layer hydrogels in the gelation and emulsification were clarified. It could conclude that the characteristic morphology, spatial conformation and structure adjustment affected heat-induced gelation and interfacial adsorption behavior. Spatial conformation and microstructure were adjusted to improve the oil and water retention by pH, ionic strength, amino acid, oil phase characteristic and protein interaction. Multi-layer hydrogels facilitated oil and water retention. The comprehensive review of gelation and emulsification mechanisms could promote the development of meat products and improvement of meat processing technology. [ABSTRACT FROM AUTHOR]

In this work, we have studied the stability constants of ternary cobalt(II) complexes with the primary ligands: pyridine-2,3-dicarboxylic acid (H22,3-Dipic, H2L) and pyridine-3,4-dicarboxylic acid (H23,4-Dipic, H2L) and secondary ligands representing low molecular mass components of blood serum: lactic acid (HLac), oxalic acid (H2Ox), citric acid (H3Cit), and phosphoric acid (H3PO4). Potentiometric data were analyzed using the least squares computational program LETAGROP. Ionic strength and temperature were both kept constant using 1.0 mol dm−3 NaNO3 as ionic medium at 25 °C. Species distribution diagrams were generated to determine the speciation variations with respect to pH. [ABSTRACT FROM AUTHOR]

The distribution equilibria of Am(III) and Cm(III) between the organic phase of bis(2,4,4-trimethylpentyl)dithiophosphonic acid (purified Cyanex301, HA) in xylene and aqueous solutions containing varying concentrations of formic acid or glycolic acid have been investigated aiming at the separation of the two actinides from each other after the groups separation of Am(III)/Cm(III) from Ln(III) ions. The apparent extraction constants for Am(III) and Cm(III) in the Cyanex301-xylene system are determined to be −8.84 and −9.37, respectively, at 0.01 M ionic strength. The specific ion interaction method (SIT) is used to obtain the stability constants of Am(III) and Cm(III) with nitrate and glycolate for calculating the speciation of the ions in extraction at 25°C and I = 0.01 M. The separation of Cm(III) from Am(III) loaded in 0.5 M HA in xylene can be considerably improved by emplying 0.01 to 0.05 M formic acid or glycolic acid as selective stripping reagents favoring complexation with Cm(III). Specifically, with 0.01 M formic acid or glycolic acid in the aqueous phase, the separation factor (SF) for Am(III) over Cm(III) is improved from 3.61 to 5.87 and 5.26, respectively. Hence, both separations of An(III) from Ln(III) and then Am(III) from Cm(III) are achieved by a selective extraction process at first and then a selective stripping process in one simple efficient system using purified Cyanex301 as extractant in organic phase and carboxylic acids as stripping chelates in aqueous. [ABSTRACT FROM AUTHOR]

Rare-earth metallic ore in Siping city had produced wastewater containing ytterbium, which has caused certain environmental pollution. In view of the low removal efficiency of ytterbium in wastewater, we developed a novel PAN microtube ultrafilter device with organic P-204 system (UF-OP). The UF-OP had organic P-204 system containing wastewater part with buffer solution acetic acid and enrichment part with nitric acid solution and organic P-204[Di(2-ethylhexyl) phosphoric acid] dissolved in gasoline. Many factors of ytterbium(III) extraction using UF-OP need to explore. The effects of hydrodynamic properties and UF system parameters on the UF-OP process for ytterbium(III) extraction were also studied. The experimental results show that the best extraction conditions of ytterbium(III) were obtained as that nitric acid concentration was 4.00 mol/L, organic P-204 concentration was 0.150 mol/L, and O/W was 0.5 in the enrichment part, and pH value was 4.80 in the wastewater part. Ionic strength of metallic ore wastewater had no obvious effect on ytterbium(III) extraction. When cinit of ytterbium(III) concentration was 1.48 × 10−4 mol/L, the extraction percentage of ytterbium(III) was up to 94.8% in 160 min. The study results would provide theoretical and technical support for the treatment of wastewater containing ytterbium in metallic ore. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have a tremendous potential to sorb hydrophobic organic contaminants in the soil environment. The effects of MPs in the soil systems, however, remain largely unexplored. The objective of this study was to investigate the impact of polyethylene and polystyrene MPs on the transport of the benzo[a]anthracene (BaA) and benzo[a]pyrene (BaP) in soil matrices. In this study, we investigated the sorption process of BaA and BaP in batch sorption experiments in a laboratory and systematically evaluated the particle sizes of MPs (0.8, 50, 200, and 500 μm) and the environmental factors, such as pH, ionic strength, and humic acid (HA) concentration on adsorption behaviour. The results showed that the adsorption of PAHs onto MPs reached equilibrium within 24 h. The adsorption kinetics of PAHs onto MPs were fitted well with the pseudo-first-order kinetic model. The adsorption isotherm modelling showed a better fit of the adsorption results to the Freundlich model. The thermodynamic research indicated the adsorption of BaA and BaP as spontaneous and endothermic processes. Additionally, the adsorption capacity of BaA and BaP reached the highest when polyethylene and polystyrene MPs with a particle size of 0.8 μm and 50 μm, respectively. The sorption of BaA and BaP on PE and PS MPs was significantly influenced by pH and the peaking at pH 5.0 and 7.0, respectively. Furthermore, the adsorption mechanisms of the BaA and BaP on MPs were dominated by electrostatic interaction, π–π interactions, and hydrophobic interaction. [ABSTRACT FROM AUTHOR]

Plastics and antibiotics are two classes of emerging contaminants with proposed negative impacts on aqueous ecosystems. In this paper, the adsorption of Ciprofloxacin (CIP) from water in studies using plastic-based adsorbents over the last half-decade was reviewed. The objectives of this review were to 1) review the procedures in the development of plastic-based material for CIP removal; 2) review the experimental designs adopted for CIP removal by plastic-based material; 3) summarise the factors affecting the CIP adsorption behaviour of plastic-based material; 4) explore the primary mechanism by which plastic-based material adsorb CIP; 5) evaluate the reusability of the plastic-based materials and 6) identify deficiencies in existing research on the adsorption of CIP by plastic-based materials and give suggestions for further study. We observed that mainly four categories of materials have been used including native plastic-based adsorbents, chemically modified plastic-based adsorbents, high-energy physical treated plastic-based adsorbents, and plastic-based composite adsorbents. The highest removal rate was recorded for the composite (99.1%). Experimental designs are mainly batch while columns have been scantly used. Changes in the pH, contact time, initial concentration, temperature, and ionic strength also affect the adsorption capacity. The most common mechanism by which CIP was adsorbed is hydrogen bonding. Additionally, electrostatic interaction and other non-covalent forces, such as polar-polar interaction, halogen bonds, and π–π interactions, are also mechanisms. The majority of current research on plastic-based material adsorption behaviour is done in labs, with little in-depth investigations of the adsorption process and affecting variables. As a result, further research on the adsorption behaviour of plastic-based materials in the environment is needed, which will help to fill that gap. [ABSTRACT FROM AUTHOR]

Dietary fiber (DF) significantly affects the quality attributes of food matrices. Depending on its chemical composition, molecular structure, and degree of hydration, the behavior of DF may differ. Numerous reports confirm that incorporating DF derived from food waste into food products has significant effects on textural, sensory, rheological, and antimicrobial properties. Additionally, the characteristics of DF, modification techniques (chemical, enzymatic, mechanical, thermal), and processing conditions (temperature, pH, ionic strength), as well as the presence of other components, can profoundly affect the functionalities of DF. This review aims to describe the interactions between DF and water, focusing on the effects of free water, freezing-bound water, and unfreezing-bound water on the hydration capacity of both soluble and insoluble DF. The review also explores how the structural, functional, and environmental properties of DF contribute to its hydration capacity. It becomes evident that the interactions between DF and water, and their effects on the rheological properties of food matrices, are complex and multifaceted subjects, offering both opportunities and challenges for further exploration. Utilizing DF extracted from food waste exhibits promise as a sustainable and viable strategy for the food industry to create nutritious and high-value-added products, while concurrently reducing reliance on primary virgin resources. [ABSTRACT FROM AUTHOR]

The peel of Hylocereus undatus was employed in the preparation of biochar and firstly applied for tetracycline removal from aqueous solution. Based on different characterization techniques, the material was found to possess a variety of surface functional groups on a porous structure and a pH point of zero charge (pHpzc) of 9.3. Adsorption of tetracycline (TC) was conducted under varying conditions, revealing significant effects of carbonization temperature, solution pH, adsorbent dose, ionic strength, contact time and initial concentration of TC on the biochar adsorption capacity. Kinetic data on TC adsorption were best described using the Elovich kinetic model, with an initial adsorption rate of 167.3 mg g−1 min−1. Isotherm data on adsorption of the desired biochar showed the best fit with the Temkin isotherm model, followed by the Langmuir model, displaying maximum adsorption capacity at 12.4 mg g−1. The electrostatic interactions between the charged biochar surfaces and certain fractions of TC were proposed as the major mechanism, together with H-bonding, pore-filling effect and π–π interaction. This study demonstrates great potential of H. undatus peel as a starting material to prepare an effective and reusable adsorbent in the removal of TC. NOVELTY STATEMENT: Literature is available on a large number of plant-based biochar adsorbents for the removal of antibiotics. However, to the best of our knowledge, no report has been published on applying biochar derived from Hylocereus undatus peel for antibiotics removal. This type of fruit peel is available in massive amounts in Vietnam and is considered as an agricultural solid waste. Therefore, to fill the gap in the literature and to converse this leftover waste into a value-added byproduct, we chose this study to prepare H. undatus peel-derived biochar for the elimination of TC in an aqueous solution. [ABSTRACT FROM AUTHOR]

AbstractA facile rapid-combustion process was introduced for preparing magnetic CoxMgyCu(1-x-y)Fe2O4 nanoparticles, and to enhance their specific surface area and saturation magnetization, the optimization involved adjusting the element proportion, calcination temperature, and solvent amount. The optimal element proportion of x:y:(1-x-y) for CoxMgyCu(1-x-y)Fe2O4 nanoparticles was 0.1:0.7:0.2, and the effects of solvent amount, and calcination temperature were also investigated. The average particle size and specific surface area of Co0.1Mg0.7Cu0.2Fe2O4 nanoparticles calcined at 400 °C with 25 mL absolute alcohol were 17.9 nm and 56.96 m2/g, respectively; while demonstrating a saturation magnetization of 8.5 emu/g. To solve the increasingly severe issue of water pollution, these nanoparticles were employed to efficiently treat dye wastewater containing methyl blue (MB). After fitting kinetic and isotherm models, the adsorption process of magnetic Co0.1Mg0.7Cu0.2Fe2O4 nanoparticles for MB dominated by chemisorption and was a multilayer adsorption process. The adsorption isotherm experiments revealed a remarkable maximum adsorption capacity of methyl blue, reaching 2255.7 mg/g, within the concentration range of MB from 400 to 4000 mg/L. The thermodynamic analysis indicated the spontaneity of the exothermic adsorption process. The studies on the effect of pH also led to satisfying results; while the residual adsorption capacity could still remain 91.2% initial adsorbance after 12 times recycle. The outstanding recycling ability, resistance to ionic strength, and pH resistance distinguished the magnetic Co0.1Mg0.7Cu0.2Fe2O4 nanoparticles among vast adsorbents. These results highlight the significant potential of these nanoparticles for treating dye wastewater. [ABSTRACT FROM AUTHOR]

AbstractEven after the centenary celebration of insulin discovery, there prevail challenges concerning insulin aggregation, not only after repeated administration but also during industrial production, storage, transport, and delivery, significantly impacting protein quality, efficacy, and effectiveness. The aggregation reduces insulin bioavailability, increasing the risk of heightened immunogenicity, posing a threat to patient health, and creating a dent in the golden success story of insulin therapy. Insulin experiences various physicochemical and mechanical stresses due to modulations in pH, temperature, ionic strength, agitation, shear, and surface chemistry, during the upstream and downstream bioprocessing, resulting in insulin unfolding and subsequent fibrillation. This has fueled research in the pharmaceutical industry and academia to unveil the mechanistic insights of insulin aggregation in an attempt to devise rational strategies to regulate this unwanted phenomenon. The present review briefly describes the impacts of environmental factors of bioprocessing on the stability of insulin and correlates with various intermolecular interactions, particularly hydrophobic and electrostatic forces. The aggregation-prone regions of insulin are identified and interrelated with biophysical changes during stress conditions. The quest for novel additives, surface-active agents, and bioderived peptides in decelerating insulin aggregation, which results in overall structural stability, is described. We hope this review will help tackle the real-world challenges of insulin aggregation encountered during bioprocessing, ensuring safer, stable, and globally accessible insulin for efficient management of diabetes. [ABSTRACT FROM AUTHOR]

AbstractTo investigate the effect of ionic strength and pH on the interfacial adsorption capacity and emulsion stability of soy hull polysaccharide (SHP), a series of SHP emulsions with 10% oil content was prepared with 0–0.30 mol/L Na+ at pH 3.0 and 5.0. The results of droplets size, zeta potential, dilatational rheological, and cryo-scanning electron microscopy analyses showed that the droplets of the emulsion at pH 3.0 were smaller and the system was more stable than at pH 5.0, and Na+ effectively shielded the negative charge on the SHP surface, leading to more SHP adsorption to the interface and increasing viscosity; whereas too much Na+ weakened the repulsive forces between droplets, making it easier for the droplets to merge with each other and causing emulsion destabilization. The best emulsification capacity of SHP was achieved at pH 3.0 with 0.10 mol/L Na+, in which 58.62 ± 0.49% SHP would adsorb to the interface, and kept high zeta potential of interface with −30.00 ± 0.27 mV. Meanwhile, the emulsion prepared under this condition had good storage stability and exhibited small droplet size of 2.425 ± 0.004 µm after 30 days. In conclusion, above indicators demonstrated that SHP-stabilized emulsions were influenced by pH and Na+, this provides theoretical and practical support for selecting the most suitable acid-base and ionic environment to prepare food emulsion by SHP, or other anionic polysaccharides. [ABSTRACT FROM AUTHOR]

A kinetic-spectrophotometric method has been devised to analyze the oxidation reaction of Para-aminobenzyl alcohol [PABAlc] catalyzed by Ag (I). PABAlc is used in numerous fields of pharmaceutical and medicinal chemistry as intermediates. The harmful effects of PABAlc cannot be overlooked in spite of its manifold applications. The toxicity of PABAlc may lead to allergic reactions, serious eye damage, respiratory tract infections amongst few. It became utmost important to formulate a method to establish the presence of PABAlc in a particular sample of water in order to circumvent its proximity to common people. In our work, we have provided an insight to an oxidation process using PABAlc as substrate catalyzed by Ag (I) ions besides proposing a reaction mechanism of the reaction under study with substantial data in the form of different thermodynamic parameters like activation energy (55 kJ/mol−1), temperature coefficient (1.92), enthalpy of activation (52.89 kJ/mol−1), alongside deets related to various effects of oxidant, substrate, catalyst, temperature, pH, ionic strength, and so on, on reaction kinetics. Additionally, the product formed in the proposed mechanism has its commercial importance in the field of pharmacy, dyes, and so on, sufficient enough to put forward a rationale for the investigations. [ABSTRACT FROM AUTHOR]

Scientists have become interested in treating dye-contaminated water due to the health issues and ecological imbalances caused by the presence of these injurious compounds in water. Herein, two MnO2 polymorphs i.e. ε- and γ-MnO2 were prepared by the comproportionation reaction between KMnO4 and MnCl2. In comparison to γ-MnO2, ε-MnO2 has greater surface area, pore width, and pore volume. According to the thermal study, ε-MnO2 contains more surplus mass in the form of negatively charged surface hydroxyl groups than γ- phase. The adsorption capability of both polymorphs was examined for the removal of both cationic (methylene blue, malachite green and crystal violet) and anionic dyes (eosin yellow). The efficient adsorption for the cationic dyes using ε-MnO2 was occurred in the neutral medium, where it had a highly negative surface as determined by zeta potential measurements. It only took few minutes to complete the removal. The electrostatic interactions of the cationic dye molecules with the OH- groups account for this result. While, complete dye removal (40 min) was occurred in the acidic medium using γ-MnO2. On the other hand, in the neutral medium the adsorption of the anionic dye molecules on the surface of both MnO2 phases was hampered by the repulsion forces. As a result, despite extending the contact time to 180 min and the adsorbent dose to 50 mg, no anionic dye removal was seen. On the contrary, in the acidic medium very fast removal occurs for Eosin Y as the surface of both MnO2 phases acquired a positive charge. The influence of the ionic strength on MB elimination was investigated. The results showed that as the content of NaCl was increased, the removal effectiveness decreased from 100% to 35%. The kinetics of cationic dye adsorption on the ε-MnO2 surface was studied, and it was discovered that the mechanism follows a pseudo-second order model. [ABSTRACT FROM AUTHOR]

Myofibrillar protein (MP), as the main meat protein, have high nutritional value. However, the relatively poor solubility of MP at low ionic strength sometimes limits the utilization of MP to produce products rich in meat protein. Accordingly, appropriate modification of MP is needed to improve their functional properties. In general, MP modification strategies are categorized into biochemical and physical approaches. Different from other available reviews, the review focuses on summarizing the principles and applications of several techniques of physical modification, briefly depicting biochemical modification as a comparison. Modification of MP with a certain intensity of direct current magnetic field, ultrasound, high pressure, microwave, or radio frequency can improve solubility, emulsification, stability, and gel formation. Of these, magnetic field and microwave-modified MP have shown some potential in reducing salt in meat. These physical techniques can also have synergistic effects with other conditions (temperature, pH, physical or chemical techniques) to compensate for the deficiencies of individual treatment techniques. However, these strategies still need further research for practical applications. HIGHLIGHTS The current status and findings of research on direct current magnetic field in meat processing are presented. Several physical strategies to modify the microstructure and functional properties of MPs. The synergistic effects of these techniques in combination with other methods to modify MPs are discussed. [ABSTRACT FROM AUTHOR]

In this study, a Taguchi experimental design was used for optimzing the immobilization of the lipase Eversa® Transform 2.0 (EVS) onto a hybrid support consisting of chitosan (CHI) and agarose (AGA), with glutaraldehyde (GLU) used as the support activator. The biocatalyst obtained was characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetry (TGA), Energy Dispersive Spectroscopy (EDS), and Scanning Electron Microscopy (SEM). The optimized reaction conditions (60 min, 5 mM ionic strength, 1% GLU concentration, and 5 mg protein load per g of support) resulted in a highly active biocatalyst (74.39 ± 0.48 U/g) and delivered an immobilization yield of 74.20 ± 0.28%. The biocatalyst produced was observed to lose only 15.3% of its activity after 61 days of storage. The activity was also observed to increase by 96.70% ± 0.76, 27.34% ± 2.34, and 84.35% ± 1.68 in the presence of the organic solvents hexane, cyclohexane, and methanol, respectively. Additionally, the byocatalist showed more pronounced activity at temperatures above 50 °C and was still able to retain approximately 30% of it at 70 °C. These values were found to be higher at alkaline pHs, as the activity of Eversa® 2.0 Transform saw an increase of up to 140% at pH 9. The desorption tests performed did not reveal any enzymatic detachment from the support. The novel biocatalyst also showed promising ester-lubricating properties. Furthermore, the in silico study revealed a binding affinity of −5.1 kcal/mol between oleic acid and the enzyme, suggesting that the combination of the substrate and the lipase was more stable and therefore, suitable for esterification. [ABSTRACT FROM AUTHOR]

Biocompatible fatty acids are natural biological materials which exhibit widespread biomedical applications. Nevertheless, their application in vesicle forms is hampered by strong pH sensitivity and poor stability to changes in ionic strength, temperature, and storage. In the investigation, the incorporation of alkyl glycoside (APG), a surfactant with non-ionic properties, into the oleic acid (OA) vesicles was undertaken as a means to address this issue. The newly formed OA/APG composite vesicles form in a pH range of between 5.4 and 7.4, which is close to the pH range of the physiological environment. The stability studies results showed that the OA/APG composite vesicles have excellent stability in terms of ionic strengths, temperature and storage. The formation of NAR-loaded OA/APG composite vesicles was demonstrated through FT-IR, DSC and XRD. In vitro topical delivery and skin retention studies confirmed that the composite vesicles improve skin permeation rate and have better skin permeation behavior. Antioxidant activity experiments confirmed that the antioxidant effect composite vesicles were significantly increased as compared to the naringenin (NAR). This finding has theoretical implications for the use of drug-loaded fatty acid vesicles in cosmetics industries and topical delivery systems. [ABSTRACT FROM AUTHOR]

The presence of micropollutants, such as caffeine (CAF), has been detected throughout the world, since conventional treatment plants are not able to properly degrade them. CAF is a widely consumed stimulant, and has been demanding the development of efficient methodologies for its removal. Aiming at the agriculture waste valorization, a new hydrochar was developed based on chemical and thermal modification of peach stones (mod-PS) for CAF removal from water and from a synthetic mixture. The morphology, functional groups and surface electrical charge of the adsorbent were characterized by SEM, FTIR and zeta potential, respectively. Regarding CAF adsorption performance, the equilibrium time was reached at 480 min and the pseudo-second-order model presented the best fit for the experimental data. The maximum adsorption capacity was 68.39 mg g-1 (298 K) and the Langmuir model exhibited a better fit for the isothermal data. The thermodynamic properties confirmed that the process was exothermic, spontaneous and reversible. The main adsorption mechanisms were hydrogen bonds and π-interactions. The global removal efficiency was satisfactory in the synthetic mixture simulating real wastewater (67%). Therefore, the proposed new hydrochar has potential application as a low-cost adsorbent for CAF removal. [ABSTRACT FROM AUTHOR]

Intelligent or smart polymer materials are those which are either "active" or responsive to a variety of environmental stimuli, such as changes in pH, temperature, ionic strength or electric field, or the presence of a specific chemical substrate. A thermally sensitive polymer, poly(N-isopropylacrylamide) (PNIPAAm), has been of great interest because aqueous solutions of PNIPAAm undergo fast, reversible switching of hydrophilicity/hydrophobicity around 32 °C at their lower critical solution temperature (LCST) of about 29–38 °C (different with variations in their structure). PNIPAAm chains show an expanded conformation in water below the LCST because of strong hydration and change to the compact forms above the LCST by sudden dehydration; this is the reversible switching effect of hydrophilic to hydrophobic. These switchable materials may have wide applications in functional textiles, controllable drug release and special fibers. Electrospinning is a simple, convenient, and versatile technique for generating fibers with diameters that range from several micrometers to tens of nanometers. Herein, we report an electrospinning method to prepare nano PNIPAAm fiber and their thermal response was characterized. Based on the results, the diameters of the PNIPAAm nanofibers within the respective system were around 200 nm and beads-less; they were successfully prepared by an electrospinning method in all cases and the reversible switching with LCST (32 °C) feature was observed clearly in the fibers. [ABSTRACT FROM AUTHOR]

At this present investigation, sugarcane bagasse magnetic graphene oxide (SCBMGO) was synthesised in several stages and used to remove Acid Red 14 dye under LED visible light. XRD, FT-IR, SEM, EDX, VSM and pHPZC analyses demonstrated the structural characteristics. The effect of variables like the pH, catalyst dose, dye concentration, hydrogen peroxide, purging gases, organic compounds, ionic strength, and comparison of different processes, radical scavengers, and reusability on AR14 removal efficiency were investigated. The most removal efficiency occurred under ideal situation: [AR14]0 = 10 mgL−1, SCBMGO dosage = 0.5 gL−1, pH = 3, hydrogen peroxide = 5 mM, and contact time equal to 120 minutes. Except for the dose, the efficiency of photocatalytic removal of AR14 decreased with the addition of other variables. AR14 photocatalytic removal obeyed the pseudo-second-order reaction kinetic. The EEO value for LED/SCBMGO (59.62 kWh/m3) process, as a function of removal proficiency, illustrated that this process was elevated productivity and diminished the cost of electrical energy consumed by the system. The highest removal efficiency of AR14 occurred in the LED/SCBMGO process (89.85%). In addition, recycling test efficiency was the same at the beginning, and the 6th stage. The removal efficiency of AR14 in drinking water was (71.45%). SCBMGO, as an effective and environmentally friendly catalyst, can be used in removing AR14 dye and organic pollutants of aqueous environments under the LED visible light. [ABSTRACT FROM AUTHOR]

In this study, nanoparticles of calcium oxide (CaO-NPs) were prepared via the sol-gel technique and introduced as a highly efficient adsorbent for removing Ni(II) from aqueous media. The prepared adsorbent was characterised via SEM, TEM, FTIR, XRD, and TGA. The pHzpc and surface area were also determined. XRD pattern exposed a polycrystalline nature of the adsorbent. SEM analysis showed that the adsorbent possesses enhanced surface porosity highlighting its potential capacity for adsorption. TEM analysis confirmed the crystallisation of adsorbent with a simple cubic structure. The FTIR spectrum displayed that the adsorbent surface comprises mostly (–OH and C=O) groups which are principally accountable for the adsorption of Ni(II). A series of batch adsorption experiments were done to study the effect of several parameters as pH, adsorbent dose, time of contact, initial concentration of adsorbate, temperature, ionic strength, and presence of interfering ions on the removal of Ni(II) ions from aqueous solutions using CaO-NPs. Maximum removal was obtained with 200 mg of adsorbent after 90 min contact time at pH 7 and 25°C as optimal conditions. The adsorption process was fitted well with Langmuir isotherm model and pseudo-second-order kinetic model, showing that the adsorption of Ni(II) ions on CaO-NPs was monolayer coverage with 166.67 mg/g capacity of adsorption. Thermodynamic studies revealed a spontaneous and endothermic adsorption process. The regeneration study using Na2EDTA indicated that the prepared adsorbent has a high renewal potential without notable loss in its performance. Moreover, the prepared adsorbent proved its good applicability and performance by successful application of the suggested procedure for the recovery of Ni(II) added to some real water samples. Accordingly, the obtained results showed that CaO-NPs can rapidly and efficiently remove Ni(II) from aqueous solutions. Also, CaO-NPs adsorbent is eco-friendly, easy to produce, cost-effective, non-toxic, and with good adsorption-desorption capacity. Therefore, this study will contribute to ecological cleaning and wastewater treatment. [ABSTRACT FROM AUTHOR]

Nowadays, legumes are considered as a good source of plant-based proteins to replace animal ones. They are more favorable regarding environmental aspects and health benefits, therefore many people consider moving toward a greener diet. Interestingly, recent consumer trends are promoting pea and faba bean as alternatives to soybean. Both are rich in protein and a good source of essential nutrients and minerals (calcium). However, these advantages can be partially impaired due to their high phytic acid content. This natural polyphosphate is a major antinutrient in plant-based foods, as it can bind minerals (particularly calcium) and proteins, thereby reducing their digestibility and subsequent bioavailability. Indeed, complexes formed are insoluble and limiting the absorption of nutrients, thus lowering the nutritional value of pulses. To understand and overcome these issues, the present review will refine specific mechanisms involved in assemblies between these three essential compounds in legumes as soluble/insoluble binary or ternary complexes. Molecular interactions are influenced by the environmental medium including pH, ionic strength and molar concentrations modulating the stability of these complexes during protein extraction. Protein/phytic acid/calcium complexes stability is of high relevance for food processing affecting not only structure but also functional and nutritional properties of proteins in legume-based foods. [ABSTRACT FROM AUTHOR]

Enzymes are readily inactivated in harsh micro-environment due to changes in pH, temperature, and ionic strength. Developing suitable and feasible techniques for stabilizing enzymes in food sector is critical for preventing them from degradation. This review provides an overview on chitosan (CS)-based enzymes encapsulation techniques, enzyme release mechanisms, and their applications in food industry. The challenges and future prospects of CS-based enzymes encapsulation were also discussed. CS-based encapsulation techniques including ionotropic gelation, emulsification, spray drying, layer-by-layer self-assembly, hydrogels, and films have been studied to improve the encapsulation efficacy (EE), heat, acid and base stability of enzymes for their applications in food, agricultural, and medical industries. The smart delivery design, new delivery system development, and in vivo releasing mechanisms of enzymes using CS-based encapsulation techniques have also been evaluated in laboratory level studies. The CS-based encapsulation techniques in commercial products should be further improved for broadening their application fields. In conclusion, CS-based encapsulation techniques may provide a promising approach to improve EE and bioavailability of enzymes applied in food industry. Enzymes play a critical role in food industries but susceptible to inactivation. Chitosan-based materials could be used to maintain the enzyme activity. Releasing mechanisms of enzymes from encapsulators were outlined. Applications of encapsulated enzymes in food fields was discussed. [ABSTRACT FROM AUTHOR]

A simple and green hydrophobic magnetic ionic-liquid assisted dispersive liquid-liquid microextraction (MIL-DLLME) was optimized for the determination of trace cadmium (Cd (II)) in environmental and food samples by flame atomic absorption spectrophotometer. To achieve selective and sensitive extraction of Cd (II), four MILs were prepared and tested. Extraction parameters of the MIL-DLLME including pH, type and volume of the MIL, type and volume of dispersive solvent, extraction cycle, ionic strength and sample volume were investigated in detail and optimized by Box–Behnken design. Under optimum conditions, matrix effect, recovery study, intra-day and inter-day precision were performed for the MIL-DLLM. The analytical characteristics such as limit of detection, limit of quantification and pre-concentration factor were 0.17, 0.56 and 125 ng mL−1, respectively. The validation of the MIL-DLLME was evaluated by analysis of reference materials. Moreover, the accuracy of the results in the analysis of real samples was evaluated by standard addition and quantitative recoveries (91 ± 5–101 ± 2%) were achieved. The results obtained in the analysis of both reference materials and real samples showed that the MIL-DLLME has a selective applicability for cadmium. [ABSTRACT FROM AUTHOR]

The removal of Congo Red dye from an aqueous solution using the soil from Fesdis (FS) area (Batna, Algeria) was studied. The soil was characterised using ATR, BET, SEM and XRF techniques. The characterisation results showed the existence of clay, carbonate and quartz in this soil. The adsorption results demonstrated that the CR dye adsorption onto the Fesdis soil is dependent on the different investigated parameters as the biosorbent concentrations, the pH, the initial dyes concentrations, temperature and the ionic strength effect. The results show that the dye removal was increased with the raise of the reaction temperature, adsorbent dose, and dye initial concentration. The efficiency dye removal increased to 96% and achieved the value 99% when CaCl2 was added. The optimum conditions determined at room temperature were [dye] = 50 mg/L, [adsorbent] = 12 g/L, neutral pH with a maximum adsorption capacity (qmax) was around 6.693 mg.g−1. Equilibrium isotherms were analysed by the Langmuir model, Freundlich model, and the Dubinin–Radushkevich models. The pseudo-first-order, the pseudo-second-order and intraparticle diffusion models were used for kinetic analysis. The thermodynamic study reveals that CR dye adsorption onto the Fesdis soil is a spontaneous, physical and endothermic process. [ABSTRACT FROM AUTHOR]

In this investigation, we employed chemical oxidative copolymerization techniques to produce cross-linked polyaniline/chitosan-graphene oxide-oxidized single-wall carbon nanotubes (Cross PANI/Chito-GO-OXS NCs) as a network to increase the surface area, as well as the active centers to enhance the efficiency of the adsorption of anionic and cationic dyes. This novel material was utilized as an adsorbent for decontaminating water by eliminating acid red dye (AR1) and brilliant green dye (BG). Several analytical techniques were employed to assess the composition and structure of the synthesized adsorbent, including scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and Raman spectroscopy. To assess the efficacy of Cross PANI/Chito-GO-OXS NCs in dye removal, batch experiments were carried out under diverse conditions, such as varying pH, adsorbent quantity, agitation duration, ionic strength, and temperature. The results indicated that the optimum conditions for AR1 removal were achieved at pH 2, using 5 mg of Cross PANI/Chito-GO-OXS NCs at a concentration of 20 mg/L for 120 min. Conversely, for BG removal, the most favorable outcomes were observed at pH 6, with the use of 5 mg of Cross PANI/Chito-GO-OXS NCs at a concentration of 5 mg/L for 120 min. Under these operating conditions, the maximum removal efficiency for actual wastewater was determined to be 96.73% for AR1 dye and 95.55% for BG dye. Additionally, we analyzed the adsorption isotherm data utilizing various models. The adsorption kinetics were elucidated through a pseudo-second-order model, supported by regression data, which yielded R2 values of 0.9839 for AR1 and 0.9928 for BG, respectively, describing the adsorption of both dyes onto Cross PANI/Chito-GO-OXS NCs. Furthermore, the thermodynamic analysis revealed that the removal of AR1 dye is an endothermic process, while BG dye removal is exothermic, and both removal of AR1 and BG dyes are spontaneous and chemisorption processes. [ABSTRACT FROM AUTHOR]

This article describes an easy and simple method to remove a toxic Acid Red dye from aqueous solution. Ternary poly(O-toluidine)/graphene oxide/chitosan P(OT)/GO/CS nanocomposites (NCs) were fabricated by an oxidative polymerization technique to remove Acid Red (A.R.) dye from aqueous solutions using solid-phase extraction. The P(OT)/GO/CS NCs exhibit a metal sieve-like structure consisting of GO nanosheets and a core shell-shell porous structure, which provides several adsorption sites and channels for the transport of dye molecules. FTIR, XRD, RAMAN, TEM, SEM, BET, and TGA-DTG investigations were carried out on NCs. To investigate the removal effectiveness of the NCs using adsorbent dose, pH and solution temperature, shaking time, and ionic strength. Experimental adsorption findings, utilizing 15 mg of solid-phase NCs, can remove the majority of the A.R. dye in 75 min at pH 2.0 with an adsorption efficiency and an adsorption capacity of 99.6% and 169.5 mg/g, respectively. The pseudo-second-order kinetic model best captures the adsorption process of A.R. dye on the NC solid phase, according to experimental data. Thermodynamically, the removal process was endothermic, spontaneous, and associated with increasing randomness. Finally, NCs were tested by removing A.R. dye from real samples. NCs removed A.R. dye from aqueous solutions for four cycles. [ABSTRACT FROM AUTHOR]

This paper deals with the valorization of the native Carpobrotus edulis plant (C. edulis) as a bioadsorbent for the removal of toxic dyes such as Rhodamine B (RB) and Congo Red (CR). This plant was further characterized by BET, SEM, EDX, and FT-IR methods. The colorants were applied in a batch adsorption experiment that included measurements of adsorbent ratio, ionic strength, contact time, initial concentration, pH, and temperature. It was observed that for 100 mg/L initial dye concentration, 0.2 g of C. edulis showed maximum adsorption efficiency for RB (> 75%), while 0.4 g for CR (> 70%). For both dyes on the biomaterial tested, ionic strength and pH have no significant impact on the adsorption. Adsorption fits a pseudo-second order kinetic model and Langmuir isotherm. The optimum adsorbed amount of C. edulis was indicated at 56.18 and 19.84 mg/g for RB and CR, respectively. The results of the thermodynamic study show that the adsorption process of the dyes by the biomaterial is spontaneous and exothermic with a decrease in the randomness of the adsorption process. The results of the regeneration indicate that the bioadsorbent was efficiently recycled with 55.80% and 36.26% uptake for RB and CR dyes, respectively, after 3rd cycles of desorption-adsorption. Operational factors were studied using Taguchi's experimental design. Our experimental results confirm the importance of the influence of initial concentration, adsorbent ratio, and contact time on adsorption with maximum adsorption of RB and CR was found to be 76.06% and 68.18% dye, respectively. [ABSTRACT FROM AUTHOR]

A massive amount of tea waste was generated in tea processing. In order to fully utilize tea waste, tea waste microcrystalline cellulose (MCC) was used as stabilizer without any other treatment to fabricate Pickering emulsion. Emulsion was produced by high pressure homogenization and characterized in terms of physicochemical parameters, morphologies and stabilities. High MCC concentration, high pH, low oil-water ratio and low ionic strength were benefited for emulsion stability. Pickering emulsions stabilized by MCC were stable for 42 days with the MCC concentration of 1.00% and 2.00%, oil-water ratio of 1:9, pH of 7.0 and ionic strength of 0 mM. Encapsulation in Pickering emulsion stabilized by MCC enhanced the stability of lycopene against photodegradation and thermal degradation, and high concentration of MCC promoted protection. Lycopene loaded in Pickering emulsion showed high stability and bioaccessibility during simulated digestion in vitro. Tea waste MCC could be used to prepare low fat and low salt Pickering emulsions, and provided perspective on high value-added utilization of tea waste. [ABSTRACT FROM AUTHOR]

Neutral red (NR) and safranin-O (SO) dyes are used in industrial processes, which their inappropriate disposal in surface waters causes negative impacts. Alternative techniques have been investigated for the complete removal of dyes, in which the adsorption presents itself as a feasible option, especially when low-cost adsorbents obtained from industrial waste are used, such as soybean hulls (SBH). This study proposed the use of SBH for the adsorption of NR and SO dyes. The characterization showed heterogeneous and porous morphology with predominantly negative surface charges, which favored the fixation of the cationic dyes. The comparative study of SO and NR adsorption onto SBH and commercial granular activated carbon confirmed the good performance of the biosorbent material. The maximum adsorption capacities were 287.30 and 221.74 mg g−1 for NR and SO onto SBH, respectively. The equilibrium time was reached in 90 minutes for both dyes. The experimental data was adjusted to the Langmuir and pseudo-second-order models. Thermodynamics inferred endothermic, spontaneous and reversible characteristics to adsorptive processes. The main proposed adsorption mechanisms were hydrogen bonds, π-interactions and electrostatic interactions. The regeneration study showed the possibility of reusing SBH for 6 cycles, and the effect of ionic strength found that the adsorption efficiency was not reduced. Therefore, SBH demonstrated versatility and efficiency in the removal of cationic dyes from wastewater, evidencing its industrial applicability. [ABSTRACT FROM AUTHOR]

Gas-assisted low-gradient magnetic separation (GAMS) was proposed for removing Congo red (CR) from wastewater. GAMS included the adsorption removal process of nanoparticles for CR and GAMS recovery process for CR-loaded nanoparticles from wastewater. Polyethylene glycol (PEG) modified Fe3O4 (Fe3O4/PEG) nanoparticles showed maximum saturated adsorption capacity of 133.3 mg/g. The results indicated that the adsorption process conditions changed the loading amounts of CR on Fe3O4/PEG nanoparticles, showing indirect effect on the separation efficiency of GAMS. And the separation performance of GAMS could be significantly improved by changing gas flow rate, ionic strength, pH, and dyes loading amounts on nanoparticles. The comparison results of MS and GAMS suggested that the limitation of magnetic force on the capture distance could be overcome and the separation efficiency of MS could be significantly improved by the bubbles. These made it feasible to rapidly recover dyes-loaded nanoparticles from large volume wastewater. GAMS combined the efficient removal of dyes by magnetic nanoparticles with rapid recovery of dyes-loaded nanoparticles from large volume wastewater, showing great potential for wastewater treatment. [ABSTRACT FROM AUTHOR]

Oil (or petroleum), consisting of a mixture of hydrocarbons, can leak from oil exploration, production, and use. Due to their complex mixture and interaction with the subsurface soil and water, they are hard to treat and can become a significant environmental concern. Rhamnolipid and sophorolipid biosurfactants, biologically produced surfactants, can be used to remove petroleum hydrocarbons. Nanoparticles have gained attention as promising materials for soil remediation. In this study, suspensions of Fe-Cu nanoparticles and biosurfactants were employed for the remediation of oil-contaminated soil. The results showed that these suspensions displayed a high oil removal rate from contaminated soil, which followed the first-order reaction. For batch experiments, the oil remediation efficiency was up to 84%. Optimum conditions to achieve the highest oil remediation performance included a rhamnolipid biosurfactant: nanoparticle ratio of 10:1 (wt%: wt%), pH 7, room temperature, and shaking speed of 60 rpm for 60 min. The remediation rate was improved by higher temperature and lower ionic strength. In the presence and absence of nanoparticles, rhamnolipid biosurfactant demonstrated a higher remediation efficiency than sophorolipid biosurfactant and ultraplex surfactant. The presence of other surfactants decreased the treatment productivity by 9-14% compared to using only rhamnolipid biosurfactant. Nanoparticles were reused with a remediation efficiency of 59% after three cycles by rhamnolipid biosurfactant. These results suggested that biosurfactants/Fe-Cu nanoparticle suspension showed promise for the remediation of oil-contaminated soil. [ABSTRACT FROM AUTHOR]

India generates 126.6 and 42 million tons of Rice straw (RS) and Rice husk (RH) annually, respectively. These agro-processing wastes feedstock are dumped in landfills or burnt, releasing toxic gases and particulate matter into the environment. This paper explores the valorization of these wastes feedstock into sustainable, economic products. We compare these wastes as matrices for lipase immobilization. These matrices were characterized, different parameters (pH, temperature, ionic strength, and metal ion cofactors) were checked, and the selected matrix was analyzed for reusability and hydrolysis of vegetable oils. Lipase immobilized Rice straw (LIRS) showed the highest activity with 72.84% protein loading. Field emission scanning electron microscopy (FESEM) demonstrated morphological changes after enzyme immobilization. FTIR showed no new bond formation, and immobilization data was fitted to Freundlich adsorption isotherm (with K = 12.18 mg/g, nF = 4.5). The highest activity with protein loading, 91.05%, was observed at pH 8, 37 °C temperature, 50 mM ionic strength, and lipase activity doubled in the presence of Mg2+ ions. The LIRS retained 75% of its initial activity up to five cycles and efficiently hydrolyzed different oils. The results reflected that the LIRS system performs better and can be used to degrade oily waste. [ABSTRACT FROM AUTHOR]

Plant proteins have recently gained market demand and momentum due to their environmentally friendly origins and health advantages over their animal-derived counterparts. However, their lower techno-functionalities, digestibility, bioactivities, and anti-nutritional compounds have limited their application in foods. increased demand for physically modified proteins with better techno-functionalities resulted in the application of different thermal and non-thermal treatments to modify plant proteins. Novel physical processing technologies (NPPT) considered 'emerging high-potential treatments for tomorrow' are required to alter protein functionality, enhance bioactive peptide formations, reduce anti-nutritional, reduce loss of nutrients, prevention of damage to heat liable proteins and clean label. NPPT can be promising substitutes for the lower energy-efficient and aggressive thermal treatments in plant protein modification. These facts captivated the interest of the scientific community in designing novel functional food systems. However, these improvements are not verifiable for all the plant proteins and depend immensely on the protein type and concentration, other environmental parameters (pH, ionic strength, temperature, and co-solutes), and NPPT conditions. This review addresses the most promising approaches of NPPT for the modification of techno-functionalities of plant proteins. New insights elaborating the effect of NPPTs on proteins' structural and functional behavior in relation to other food components are discussed. The combined application of NPPTs in the field of plant-based bioactive functionalities is also explored. [ABSTRACT FROM AUTHOR]

Food industries attempt to introduce a new food packaging by blending essential oils (EOs) into the polymeric matrix as an active packaging, which has great ability to preserve the quality of food and increase its shelf life by releasing active compounds within storage. The main point in designing the active packaging is controlled-release of active substances for their enhanced activity. Biopolymers are functional substances, which suggest structural integrity to sense external stimuli like temperature, pH, or ionic strength. The controlled release of EOs from active packaging and their stimuli-responsive properties can be very important for practical applications of these novel biocomposites. EOs can affect the uniformity of the polymeric matrix and physical and structural characteristics of the composites, such as moisture content, solubility in water, water vapor transmission rate, elongation at break, and tensile strength. To measure the ingredients of EOs and their migration from food packaging, chromatographic methods can be used. A head-space-solid phase micro-extraction coupled to gas chromatography (HS-SPME-GC–MS) technique is as a good process for evaluating the release of Eos. Therefore, the aims of this review were to evaluate the qualitative characteristics, release profile, and stimuli-responsiveness of active and smart food packaging nanocomposites loaded with essential oils and developing such multi-faceted packaging for advanced applications. [ABSTRACT FROM AUTHOR]

A simple, green, rapid, and efficient magnet ionic liquid (MIL) dispersive liquid–liquid microextraction (DLLME) method coupled with high-performance liquid chromatography (HPLC) was successfully developed for the determination of three trace pyrethroids (fenvalerate, beta-cypermethrin, and bifenthrin) in water and food samples. Tri-hexyl-tetradecyl-phosphonium tetra-chlorocobalt (II) [P6,6,6,14+]2[CoCl42−] was explored as the extraction solvent due to its magnetic susceptibility, low ultraviolet absorbance, difficulty to hydrolyze in aqueous solution, and high extraction capacity. Important factors of extraction efficiency, such as the mass of MIL, pH, and ionic strength, were optimized. The spiked recoveries of the targets in water and food samples were from 96.3 to 103.8%. The detection limits were from 0.75 to 1.75 ng ml−1. The results indicated that the developed MIL-DLLME method based on [P6,6,6,14+]2[CoCl42−] as the extraction solution has the advantages of rapid and high efficiency and was employed to determine pyrethroids in water and food samples. [ABSTRACT FROM AUTHOR]

The main phase transition of lipid bilayers corresponds to a defined change from an ordered (gel) to a disordered (fluid liquid crystal) state of hydrocarbon chains, occurring in general at a defined temperature Tm. However, aqueous dispersions of pure anionic phospholipids, and particularly DMPG, may exhibit a 'melting regime', from Tmon until Tmoff, over ~10°C. The melting process depends on pH, ionic strength and several details of sample preparation. This paper makes a review on seven papers of the author with different collaborations, with the original proposal of pores in the DMPG melting transition. The focus is on structural results obtained from X-ray scattering, varying concentration and temperature, but integrating with results from other experimental techniques. Initially the effect of salt addition was separated from the effect of DMPG concentration. At DMPG concentrations higher than 70 mM a lamellar phase starts and a detailed study of the temperature variation of 150 mM DMPG allowed arrival to detailed pore model, focused in the surface fractions of pores in the bilayers. The model admits large and small pores in the melting regime and agrees with the new Lamellar Phase with pores (Lp) starting at T3. The large biological relevance is stressed. [ABSTRACT FROM AUTHOR]

Biosurfactant-based reverse micellar extraction of Lactoperoxidase (LP) was studied using Rhamnolipid (RL) as a biosurfactant. Different solvents were considered to select a suitable organic phase for forming reverse micelles (RM) to varying concentrations of RL for the extraction of LP from its synthetic aqueous solution. The effect of addition of nonionic surfactant as lipophilic linker, whey pH, and ionic strength of the whey was studied to improve the forward extraction of LP from acid whey. About 96.65% LP was extracted to the RM phase during forward extraction. Further, a new back extraction strategy was developed by harnessing the biosurfactant properties. The pH-specific protonation–deprotonation characteristic of the RL headgroups was exploited to overcome the back extraction of LP, which is the rate-limiting step. The back extraction in citrate buffer at pH 5 using 0.75 M KCl resulted in 85.71% active LP recovery with 8.4-fold purification. The effect of the extraction process on the antimicrobial activity of LP was further examined with S. aureus, and the multiplication of the organism was almost arrested even after 24 hr at 9°C. [ABSTRACT FROM AUTHOR]

The spatial arrangement of nanoobjects by using DNA is a promising nano-design technology. Polyadenine adhesive tails are increasingly used to anchor functional oligonucleotides on the surface of gold nanoparticles at low pH. Further hybridization of such functional oligonucleotides allows nanoparticles to be organized within the desired design. In this work, we studied the effect of temperature, ionic strength, and strand design on the adsorption rate of polyadenines on the surface of gold nanoparticles at different pH. We found that there are temperature and ionic strength ranges in which the adsorption rate increases and vice versa. There are also significant differences in the effects of monovalent sodium and divalent magnesium ions. We have shown that dual-tail DNA strand design allows for increased surface density, which is significantly higher than that obtained with the standard one-tail strand design. [ABSTRACT FROM AUTHOR]

In recent years, significant advances have been made in the field of functionalized membranes. With the functionalization using various materials, such as polymers and enzymes, membranes can exhibit property changes in response to an environmental stimulation, such as heat, light, ionic strength, or pH. The resulting responsive nature allows for an increased breadth of membrane uses, due to the developed functionalization properties, such as smart-gating filtration for size-selective water contaminant removal, self-cleaning antifouling surfaces, increased scalability options, and highly sensitive molecular detection. In this review, new advances in both fabrication and applications of functionalized membranes are reported and summarized, including temperature-responsive, pH-responsive, light-responsive, enzyme-functionalized, and two-dimensional material-functionalized membranes. Specific emphasis was given to the most recent technological improvements, current limitations, advances in characterization techniques, and future directions for the field of functionalized membranes. [ABSTRACT FROM AUTHOR]

The variation of zeta potential of high ash Indian coals in the presence of various surface modifying conditions has rarely been studied in depth. The objective of the present investigation was to perform a detailed comparative study on surface zeta potential of two distinct Indian coals that have substantial differences in their ash content and surface chemistry. Detailed characterization studies of the two coals were performed using FTIR, petrography, and proximate and ultimate analyses, which demonstrated that Topa coal was more hydrophobic in comparison to Kulda coal. Electrokinetic measurements at ambient temperatures demonstrated that the zeta potential of both coals was dependent on pH, ionic strength, and type of surfactant. The surface potential of both coals, irrespective of the extent of mineral association, was only affected by cationic surfactant over a prolonged contact time. XRD analysis of the coal ash samples revealed the presence of quartz, hematite, mica, and zeolite as the predominant minerals. In the present study, the inherent and surface chemistry of mineral-rich coals was correlated through the measurements of zeta potential. It was concluded that the variation in mineral matter content does not impact the zeta potential of coal particles significantly. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) and LDHs-derived materials are emerging as potential engineered adsorbents for the protection of water environment. Particularly, LDHs intercalated with different guest compounds (GC-LDHs), which differ from traditional interlayer anions (such as Cl−, SO42−, NO3−, CO32−, and PO43−), are widely reported by recent studies showing their promising multifunctional roles in water purification. Herein, this review systematically presents the synthesis methods and characterization techniques of GC-LDHs and their application as adsorbents in removing potentially toxic elements (PTEs) from the aqueous phase. This review also elaborates on the important roles of complexation, chelation, precipitation, isomorphic substitution, and ion exchange in the process of PTE removal by GC-LDHs. Among them, compared with PTE cations, ion exchange is an additional mechanism for the removal of PTE oxyanions by GC-LDHs. Furthermore, the influence of pH, ionic strength, temperature, physiochemical properties of original LDHs and guest compounds on the GC-LDHs adsorption performance are also summarized. Finally, the development trends and future challenges related to GC-LDHs are proposed. [ABSTRACT FROM AUTHOR]

Studies on Vanadium (V) adsorption in aqueous systems employing biomaterials friendly to the environment are rare. This study investigated the adsorption performance of the living and non-living Chlorella vulgaris (C. vulgaris) for V from aquatic systems. Vanadium inhibited the growth of living C. vulgaris. The results of isothermal equations showed that the non-living C. vulgaris biomass was favourable for V adsorption. At 400 mg L−1 V, 50 mg algae biomass, 40°C, and 0.01 M ionic strength for 24 h, the maximum adsorption capacity reached 94.00 mg g−1. The results of the kinetic studies indicated that chemisorption dominated the V adsorption process. Analysis on the surface of non-living C. vulgaris biomass revealed that hydroxyl groups, carboxylate groups, amide groups, aromatic carbons, and organic halogenated hydrocarbon groups played crucial roles in V biosorption. Vanadium was bound to the active sites on the surface of C. vulgaris through ion exchange action as opposed to redox reaction. Desorption experiments were conducted by eluting the non-living C. vulgaris biomass with 1 M NaOH solution, and the maximum desorption rate of V reached 98%. The results demonstrate that C. vulgaris is a green and highly effective biosorbent for vanadium removal from aquatic systems. [ABSTRACT FROM AUTHOR]

In this work, column experiments were applied to investigate the transport of four kinds of microplastics (MPs) under a series of ionic strength (IS) conditions. Under 0.1 mM IS, PMMA MPs showed the highest mobility, as well as the PET MPs showed the lowest mobility. With the IS increased, the transport of all kinds of MPs in porous media was generally reduced to the minimum. The transport reducing efficiency of PMMA MPs and PET MPs was lower than that of the PVC MPs and PP MPs. It was found that both the hydro-chemical conditions and basic properties showed combined effect on MPs transport in porous media. The DLVO results were well used to describe the deposition of MPs onto sand surface and excavate the transport behaviors of MPs. The one-site kinetic deposition model was successfully conducted to fit the observed breakthrough curves. Findings from this study elucidated the key factors controlling the MPs transport in porous media, contributing to the prediction and assessment of the environmental risks of MPs. [ABSTRACT FROM AUTHOR]

In this article, a size-exclusion chromatography with diode array detector (HPSEC-DAD) method was developed to determine the molecular weight distribution of natural aquatic organic matter. First, a variable screening was performed using sodium polystyrene sulphonate (PSS) standards, verifying the significant effects of ionic strength and flow rate of the mobile phase and the injection volume on resolution and final retention time. The method was then optimised using a Box – Behnken design (BBD), obtaining optimal values of 60 mM (ionic strength), 70 μL (injection volume) and 1.2 mL/min (flow rate). The process was repeated with the same design, using natural water as analyte and introducing peak area as a response, achieving optimum values of 30 mM (ionic strength), 60 μL (injection volume) and 1.17 mL/min (flow rate). In view of this discrepancy, the results of both optimal methods, using standard humic acid, were compared with the results reported in the literature, resulting in lower relative errors with the PSS method than with the natural water method. Under PSS method conditions, different samples of natural water were analysed, and it was possible to distinguish between the molecular weight profiles of organic matter coming from different environments. [ABSTRACT FROM AUTHOR]

The adsorbent ability of Al2O3 nanoparticles (ANPs) was examined to remove Cd2+ and Zn2+ from aqueous solution. The sorption of Cd2+ and Zn2+ on ANPs as a function of pH, ionic strength (IS), humic acid (HA), contact time, foreign ions and the temperature were investigated. It was observed that physico-chemical factors (pH and ionic strength) strongly affect the sorption of Cd2+ and Zn2+ on ANPs. Comparatively, the sorption of Cd2+ and Zn2+ dominated by surface complexation of the outer sphere at low pH values (pH < 8.0), while surface complexation of the inner sphere was the major sorption mechanism at elevated pH values (pH > 8.0). The maximum sorption capacity of Cd2+ and Zn2+ on ANPs calculated from the Langmuir model was 8.40 and 9.00 mg g–1 respectively at 303 K, exhibiting higher efficiency for Zn2+ sorption than Cd2+.The thermodynamic parameters (∆H0, ∆S0 and ∆G0) showed that the adsorption of Cd2+ and Zn2+ was endothermic and spontaneous. This investigation exhibited that ANP is an efficient, inexpensive process and thereby reasonable technology for the elimination of metal ions from the contaminated aqueous source. [ABSTRACT FROM AUTHOR]