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1.
Small ; 19(21): e2300233, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36843293

RESUMEN

Nowadays, the rapidly development of advanced antidetection technology raises stringent requirements for microwave absorption materials (MAMs) to focus more attention on wider bandwidth, thinner thickness, and lower density. Adding magnetic medium to realize broadband absorption may usually result in the decline of service performance and accelerating corrosion of MAMs. Chiral MAMs can produce extra magnetic loss without adding magnetic medium due to the unique electromagnetic cross polarization effect. However, more efforts should be taken to furtherly promote efficient bandwidth of chiral MAMs and reveal attenuation mode and modulation method of chiral structure. Herein, a novel superhelical nano-microstructure based on chiral polyaniline and helical polypyrrole is successfully achieved via in situ polymerization strategy. The enhanced multiscale-chiral synergistic effect contributes to broaden effective absorption bandwidth, covering 8.6 GHz at the thickness of 3.6 mm, and the minimum reflection loss can reach -51.3 dB simultaneously. Besides, to further explain response modes and loss mechanism of superhelical nano-microstructures, the electromagnetic simulation and test analysis are applied together to reveal their synergistic enhancement attenuation mechanism. Taken together, this strategy gives a new thought of how to design, prepare, and optimize the hierarchical structure materials to achieving broadband and high-performance microwave absorption.

2.
Phys Chem Chem Phys ; 25(8): 5913-5925, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36779513

RESUMEN

Traditional microwave absorbing materials (MAMs) have exposed more and more problems in multi-spectrum detection and a harsh service environment, which hinder their further application. Bionic materials and structures have attracted more and more attention from researchers in the field of stealth materials due to their excellent properties, such as high strength and high conductivity, along with easy access to scale adjustability and structural design. By introducing the concept of bionics into their structural design and material design, we can obtain highly efficient stealth materials with multiple properties. In addition, the concept of multispectral stealth is furthered by comparing the difference in the principle and methods of achievement between radar stealth and infrared stealth. This paper fundamentally summarizes the research status of bionic structure design ideas in stealth materials, analyzing the structure-activity relationship between the structural size effect and electromagnetic characteristics from low order to high order. Then, the design ideas and universal strategies of typical bionic structures are summarised and an idea for the integrated design of radar absorption compatible with infrared stealth is put forward. This will provide profound insights for the application of biomimetic stealth materials and the future development of intelligent-response and dynamically adjustable materials.

3.
J Insect Sci ; 23(3)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37352434

RESUMEN

Traditional chemical pesticides pose potential threats to human health, the environment, and food safety, and there is an urgent need to develop botanical pesticides that are easily degradable, renewable, and environmentally compatible. This research serves to detect the lethal impacts of Amanita pantherina(DC.:Fr) Schrmm.(Agaricales, Amanitaceae, Amanita), Amanita virgineoides Bas (Agaricales, Amanitaceae, Amanita), Coprinus comatus (O.F.Müll.) Pers. (Agaricales, Psathyrellaceae, Coprinus), Pycnoporus cinnabarinus(Jacq.:Fr) Karst (Polyporales, Polyporaceae, Polyporus) and Phallus rubicundus (Bosc) Fr. (Phallales, Phallaceae, Phallus) on Drosophila melanogaster(Diptera, Drosophilidae, Drosophila), including their effects on lifespan, fecundity, offspring growth and developmental characteristics, antioxidant enzyme activity, peroxide content, and the gene transcription associated with signaling pathways and lifespan of D. melanogaster. The results demonstrated that they all produced lethal effects on D. melanogaster. Female flies were more sensitive to the addition of macrofungi to their diet and have a shorter survival time than male flies. The toxic activity of A. pantherina-supplemented diet was the strongest, so that the D. melanogaster in this group had no offspring. The macrofungal-supplemented diets were able to significantly reduce the activity of antioxidant enzymes, accumulate peroxidation products, up-regulatd the transcription of genes related to signaling pathways, inhibit the expression of longevity genes, reduce the lifespan and fertility of D. melanogaster. Consequently, we hypothetically suggest that medicinal C. comatus, P. cinnabarinus and P. rubicundus hold the potential to be developed into an environmentally friendly biopesticide for fly killing.


Asunto(s)
Antioxidantes , Drosophila melanogaster , Masculino , Femenino , Humanos , Animales , Longevidad , Drosophila , Fertilidad
4.
J Sci Food Agric ; 103(4): 1846-1855, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36347624

RESUMEN

BACKGROUND: The protein-polyphenol interaction mechanism has always been a research hotspot, but their interaction is affected by heat treatment, which is widely applied in food processing. Moreover, the effects of microwave or water-bath heating on the protein-polyphenol interaction mechanism have been not clarified. The pasteurization condition (65 °C, 30 min) was selected to compare the effects of microwave or water bath on binding behavior, structure, and cell proliferation between α-lactalbumin (α-LA) and safflower yellow (SY), thus providing a guide for the selection of functional dairy processing conditions. RESULTS: Microwave heat treatment of α-LA-SY resulted in stronger fluorescence quenching than that of conventional heat treatment. Moreover, the binding constant Ka of all α-LA-SY samples was augmented significantly after microwave or water bath treatment, and microwave-heated α-LA-SY showed the maximum Ka . Fourier transform infrared spectroscopy showed that microwave heating resulted in more ordered structures of α-LA into its disordered structures than water bath heating. However, the ferric reducing antioxidant power and chroma value of α-LA-SY were more reduced by microwave heating than by water bath heating. Moreover, microwave heating facilitated the cell proliferation of α-LA-SY compared with water bath treatment. CONCLUSION: It was demonstrated that microwave heating promoted interaction between α-LA and SY more than water bath heating did. Microwave heat treatment was a safe and effective way to enhance the binding affinity of α-LA to SY, being a potential application in food industry. © 2022 Society of Chemical Industry.


Asunto(s)
Lactalbúmina , Microondas , Lactalbúmina/química , Calefacción , Calor , Factores de Transcripción , Proliferación Celular , Agua
5.
J Sci Food Agric ; 103(3): 1588-1592, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36318369

RESUMEN

BACKGROUND: Goat milk has balanced nutritional composition, is conducive to digestion and absorption, and does not easily lead to allergic reactions. However, the special goaty flavor in milk has seriously affected consumer acceptance. It is imperative to alleviate the goaty flavor in a safe and efficient way. RESULTS: This study indicated that the supplementation of 6 g kg-1 ß-cyclodextrin or 8 g kg-1 lactitol in goat milk significantly alleviated goaty flavor and improved sensory characteristics. Furthermore, the supplementation of ß-cyclodextrin and lactitol had a synergistic effect in reducing the content of free fatty acids that cause goaty flavor. The content of caproic acid (C6 H12 O2 ), octanoic acid (C8 H6 O2 ), and decanoic acid (C10 H20 O2 ) decreased by 42.46%, 39.45%, and 46.41%, respectively, after a combined group was supplemented with 6 g kg-1 ß-cyclodextrin and 7 g kg-1 lactitol, which was significantly lower than in groups given ß-cyclodextrin or lactitol individually. CONCLUSION: This study provides a novel and effective approach to alleviate goaty flavor and promote the competitiveness of goat milk products. © 2022 Society of Chemical Industry.


Asunto(s)
Gusto , beta-Ciclodextrinas , Animales , Cabras , Leche/química , Ácidos Grasos/química
6.
Arch Virol ; 167(9): 1899-1903, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35716263

RESUMEN

A novel positive-sense single-stranded RNA mycovirus, designated as "Magnaporthe oryzae botourmiavirus 10" (MoBV10), was identified in the rice blast fungus Magnaporthe oryzae isolate HF04. MoBV10 has a single genomic RNA segment consisting of 2,448 nucleotides, which contains a single open reading frame encoding an RNA-dependent RNA polymerase. Genome comparison and phylogenetic analysis indicated that MoBV10 is a new member of the genus Betascleroulivirus in the family Botourmiaviridae. The 5'- and 3'-terminal sequences of the genomic RNA of MoBV10 have inverted complementarity and potentially form a panhandle structure, which is very rare in RNA viruses.


Asunto(s)
Magnaporthe , Oryza , Virus ARN , Ascomicetos , Genoma Viral , Magnaporthe/genética , Oryza/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , ARN Viral/genética
7.
Chem Eng J ; 428: 131408, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36570598

RESUMEN

Chloroquine (CLQ) is required to manufacture on a larger scale to combat COVID-19. The wastewater containing CLQ will be discharged into the natural water, which was resistant to environmental degradation. Herein, the degradation of CLQ by ferrate (Fe(VI)) was investigated, and the biodegradability of the oxidation products was examined to evaluate the potential application in natural water treatment. The reaction between CLQ and Fe(VI) was pH-dependent and followed second-order kinetics. The species-specific rate constant of protonated Fe(VI) species (HFeO4 -) was higher than that of the FeO4 2- species. Moreover, increasing the reaction temperature could increase the degradation rate of CLQ. Besides, HCO3 - had positive effect on CLQ removal, while HA had negative effect on CLQ removal. But the experiments shows Fe(VI) could be used as an efficient technique to degrade co-existing CLQ in natural waters. During the oxidation, Fe(VI) attack could lead to aromatic ring dealkylation and chloride ion substitution to form seven intermediate products by liquid chromatography-time-of-flight-mass spectrometry (LC-TOF-MS) determination. Finally, a pure culture test showed that the oxidation of CLQ by Fe(VI) could slightly increase the antimicrobial effect towards Escherichia coli (E.coli) and reduce the toxicity risk of intermediates. These findings might provide helpful information for the environmental elimination of CLQ.

8.
Angew Chem Int Ed Engl ; 61(23): e202117698, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35315956

RESUMEN

High-silica zeolite Y (FAU) plays a vital role in (petro)chemical industries. However, the slow nucleation and growth kinetics of the high-silica FAU framework limit its direct synthesis and the improvement of framework SiO2 /Al2 O3 ratio (SAR). Here, a facile strategy is developed to realize the fast crystallization of high-silica zeolite Y, which involves the combination of high crystallization temperature, ultra-stable Y (USY) seeds and efficient organic-structure directing agent (OSDA). The synthesis can be finished in 5-16 h at 160 °C and with tunable SAR up to 18.2, and the key factors affecting crystallization kinetics and phase purity are elucidated. Moreover, the crystallization process was monitored to reveal the fast crystal growth mechanism. The high-silica products possess high (hydro)thermal stability and abundant strong acid sites, which endow them excellent catalytic cracking performance, obviously superior to commercial USY.

9.
Angew Chem Int Ed Engl ; 56(31): 9039-9043, 2017 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-28503894

RESUMEN

In the past two decades, the reaction mechanism of C-C bond formation from either methanol or dimethyl ether (DME) in the methanol-to-hydrocarbons (MTH) process has been a highly controversial issue. Described here is the first observation of a surface methyleneoxy analogue, originating from the surface-activated DME, by in situ solid-state NMR spectroscopy, a species crucial to the first C-C bond formation in the MTH process. New insights into the first C-C bond formation were provided, thus suggesting DME/methanol activation and direct C-C bond formation by an interesting synergetic mechanism, involving C-H bond breakage and C-C bond coupling during the initial methanol reaction within the chemical environment of the zeolite catalyst.

10.
Insects ; 15(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39057230

RESUMEN

Eulophidae and Pteromalidae are parasitic wasps with a global distribution and import for the biological control of pests. They can be distributed in different altitude regions, but their morphological and genetic adaptations to different altitudes are unclear. Here, we collected specimens that belong to Eulophidae and Pteromalidae from various altitudinal gradients, based on integrated taxonomic approaches to determine the species composition, and we analyzed their body shape and size from different altitudes using geometric morphometrics. Then, we performed an analysis of the D. isaea population's haplotype genes to illustrate their genetic diversity. As a result, eight species that belong to two genera, Diglyphus Walker (Eulophidae) and Pachyneuron Walker (Pteromalidae), were identified, including two newly recorded species from China (D. chabrias and D. sabulosus). Through a geometric morphometrics analysis of body shape, we found that a narrow forewing shape and a widened thorax are the significant characteristics of adaptation to high-altitude environments in D. isaea and P. aphidis. Additionally, the body size studies showed a principal relationship between centroid size and altitude; the size of the forewings and thorax increases at higher altitudes. Next, using haplotype analysis, 32 haplotypes were found in seven geographic populations with high genetic diversity of this species. Our research provides preliminary evidence for the morphological and genetic diversity adaptation of parasitic wasps to extreme environments, and these data can provide important references for investigations on the ecological adaptability of parasitic wasps.

11.
Environ Pollut ; 348: 123862, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38537799

RESUMEN

Piezo-electricity, as a unique physical phenomenon, demonstrates high effectiveness in capturing the environmental mechanical energy into polarization charges, offering the possibility to activate the advanced oxidation processes via the electron pathway. However, information regarding the intensification of Fe(VI) through piezo-catalysis is limited. Therefore, our study is the first to apply Bi2WO6 nanoplates for piezo-catalyzation of Fe(VI) to enhance bisphenol A (BPA) degradation. Compared to Fe(VI) alone, the Fe(VI)/piezo/Bi2WO6 system exhibited excellent BPA removal ability, with the degradation rate increased by 32.6% at pH 9.0. Based on the experimental and theoretical results, Fe(VI), Fe(V), Fe(IV) and •OH were confirmed as reaction active species in the reaction, and the increased BPA removal mainly resulted from the enhanced formation of Fe(IV)/Fe(V) species. Additionally, effects of coexisting anions (e.g., Cl-, NO3-, SO42- and HCO3-), humic acid and different water matrixes (e.g., deionized water, tap water and lake water) on BPA degradation were studied. Results showed the Fe(VI)/piezo/Bi2WO6 system still maintained satisfactory BPA degradation efficiencies under these conditions, guaranteeing future practical applications in surface water treatment. Furthermore, the results of intermediates identification, ECOSAR calculation and cytotoxicity demonstrated that BPA degradation by Fe(VI)/piezo/Bi2WO6 posed a diminishing ecological risk. Overall, these findings provide a novel mechanical energy-driven piezo-catalytic approach for Fe(VI) activation, enabling highly efficient pollutant removal under alkaline condition.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Hierro , Oxidación-Reducción , Sustancias Húmicas/análisis , Aniones , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
12.
Food Chem ; 457: 140096, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38905830

RESUMEN

The research explored the role of γ-oryzanol (γs) on stabilization behavior of Pickering emulsion gels (PEGs) loaded by α-lactalbumin (α-LA) or ß-lactoglobulin (ß-LG), being analyzed by experimental and computer methods (molecular dynamic simulation, MD). Primarily, the average particle size of ß-LG-γS was expressed 100.07% decrease over that of α-LA-γS. In addition, γs decreased the dynamic interfacial tension of two proteins with the order of ß-LG < α-LA. Meanwhile, quartz crystal microbalance with dissipation proved that ß-LG-γS exhibited higher adsorption mass and denser rigid interface layer than α-LA-γS. Moreover, the hydrophobic group of γS had electrostatic repulsion with polar water molecules in the aqueous phase, which spread to the oil phase. ß-LG-γS had lower RMSD/Rg value and narrower fluctuation compared with α-LA-γS. This work strength the exploration of interfacial stabilization mechanism of whey protein-based PEGs, which enriched its theoretical research for industrial-scale production as the replacement of trans fat and cholesterol.


Asunto(s)
Emulsiones , Geles , Lactalbúmina , Lactoglobulinas , Fenilpropionatos , Lactalbúmina/química , Lactoglobulinas/química , Emulsiones/química , Fenilpropionatos/química , Geles/química , Simulación de Dinámica Molecular , Tamaño de la Partícula , Interacciones Hidrofóbicas e Hidrofílicas
13.
J Ethnopharmacol ; 329: 118081, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38570148

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Liujunzi formula has been used to treat liver cancer in China for many years, but its underlying mechanism remains unclear. We previously found that decreased expression of miR-122-3p was associated with liver cancer. In this study, we aimed to explore the target of miR-122-3p and the effect of the Liujunzi formula on miR-122-3p and its downstream events in liver cancer. MATERIAL AND METHODS: Bioinformatics pinpointed potential targets of miR-122-3p. The actual target was confirmed by miRNA mimic/inhibitor transfections and a dual-luciferase reporter assay. RNA-seq looked at downstream genes impacted by this target. Flow cytometry checked for changes in T cell apoptosis levels after exposing them to liver cancer cells. Gene expression was measured by RT-qPCR, western blotting, and immunofluorescence staining. RESULTS: Cell experiments found the Liujunzi extract (LJZ) upregulated miR-122-3p and in a dose-dependent manner. Bioinformatics analysis found UBE2I was a potential target of miR-122-3p, which was validated through experiments using miRNA mimics/inhibitors and a dual-luciferase reporter assay. RNA-seq data implicated the NF-κB pathway as being downstream of the miR-122-3p/UBE2I axis, further confirmed by forcing overexpression of UBE2I. Bioinformatic evidence suggested a link between UBE2I and T cell infiltration in liver cancer. Given that the NF-κB pathway drives PD-L1 expression, which can inhibit T cell infiltration, we investigated whether PD-L1 is a downstream effector of miR-122-3p/UBE2I. This was corroborated through mining public databases, UBE2I overexpression studies, and tumor-T cell co-culture assays. In addition, we also confirmed that LJZ downregulates UBE2I and NF-κB/PD-L1 pathways through miR-122-3p. LJZ also suppressed SUMOylation in liver cancer cells and protected PD-1+ T cells from apoptosis induced by co-culture with tumor cells. Strikingly, a miR-122-3p inhibitor abrogated LJZ's effects on UBE2I and PD-L1, and UBE2I overexpression rescued the LJZ-mediated effects on NF-κB and PD-L1. CONCLUSIONS: miR-122-3p targets UBE2I, thereby suppressing the NF-κB signaling cascade and downregulating PD-L1 expression, which potentiates anti-tumor immune responses. LJZ bolsters anti-tumor immunity by modulating the miR-122-3p/UBE2I/NF-κB/PD-L1 axis in liver cancer cells.


Asunto(s)
Medicamentos Herbarios Chinos , Neoplasias Hepáticas , MicroARNs , Enzimas Ubiquitina-Conjugadoras , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Humanos , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Medicamentos Herbarios Chinos/farmacología , Apoptosis/efectos de los fármacos , FN-kappa B/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Células Hep G2 , Tolerancia Inmunológica/efectos de los fármacos
14.
Angew Chem Int Ed Engl ; 52(44): 11564-8, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-24039064

RESUMEN

Carbenium ions in zeolites: Two important carbenium ions have been observed for the first time under working conditions of the methanol-to-olefins (MTO) reaction over chabazite zeolites using (13) C NMR spectroscopy. Their crucial roles in the MTO reaction cycles have been demonstrated by combining experiments and theoretical calculations.

15.
iScience ; 26(7): 107061, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37534163

RESUMEN

Selective oxidation of methane is one of the most attractive routes for methane to chemicals. However, mechanistic understanding and avoiding over-oxidation have great challenges because of its very rapid reaction rate. Herein, a capillary micro-reaction system was introduced to monitor the initial stage of methane oxidation over platinum. For the first time, an induction period is observed, during which oxygenated intermediates, such as methanol, acetone, methyl methoxy acetate, etc., are detected. Induction period can be shortened by methane pretreatment at 600°C, which generates highly active species containing unsaturated bonds. Combined these findings and observations of in situ characterizations, the evolution route of methane oxidation over Pt is prosed, i.e., the reaction starts from the formation of initial species containing Pt-C bond, followed by the generation of oxygenated intermediates, and ended with the over-oxidation of the intermediates to CO/CO2.

16.
Food Chem ; 405(Pt A): 134827, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36370558

RESUMEN

Although sterols have multiple physiological functions, low solubility and weak emulsifying properties of sterols affect their application in the food industry. However, binding interaction between protein and sterol potentially enhances its biological activities and emulsifying properties. In this work, effects of two structurally different sterols, namely ergosterol (ES) and γ-oryzanol (γS) on binding interactions, emulsifying properties, and biological activities of whey protein isolate (WPI)-sterol complexes were investigated and compared. Fluorescence spectroscopies and molecular docking presented that binding affinity of WPI treated with γS was stronger than that with ES. Importantly, WPI-γS exhibited stronger absolute value of ζ-potential, surface hydrophobicity, emulsifying characteristics and biological activities than WPI-ES. Principal component analysis (PCA) showed that emulsifying characteristics and biological activities of all the samples were positively correlated. This study provided a theoretical basis for the development and practical application of protein-sterol complexes as functional ingredients in food industry.


Asunto(s)
Esteroles , Proteína de Suero de Leche/química , Emulsiones/química , Simulación del Acoplamiento Molecular , Interacciones Hidrofóbicas e Hidrofílicas
17.
Int J Biol Macromol ; 226: 1570-1578, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36450303

RESUMEN

Impacts of inulin addition (0, 5, 10, 15 %) on structure, functional and rheological properties of whey protein isolate (WPI) after extrusion pretreatment (E-WPI) were investigated. The results proved that after adding 15 % inulin, water holding capacity of gels, emulsifying activity, emulsion stability, foaming ability and foaming stability of E-WPI were the best and increased by 24.38 %, 7.43 %, 12.35 %, 162.97 % and 41.31 %, compared with those of unextruded WPI, respectively. Rheology analysis showed that apparent viscosity and consistency index of all the samples after inulin addition were enhanced and exhibited pseudoplastic fluids. FTIR spectroscopy indicated that E-WPI/WPI and inulin was linked together due to hydrogen bonds and addition of inulin increased the proportion of their ß-turn structure. These findings demonstrated that the addition of inulin in combination with extrusion pretreatment could jointly improve the functional properties of WPI. Therefore, E-WPI with the addition of inulin shows potential commercial applications in the production of novel food foaming agents and emulsifiers.


Asunto(s)
Inulina , Proteína de Suero de Leche/química , Viscosidad , Espectroscopía Infrarroja por Transformada de Fourier , Reología , Emulsiones/química
18.
Sci Total Environ ; 867: 161497, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36634528

RESUMEN

Disinfection is an effective process to inactivate pathogens in drinking water treatment. However, disinfection byproducts (DBPs) will inevitably form and may cause severe health concerns. Previous research has mainly focused on DBPs formation during the disinfection in water treatment plants. But few studies paid attention to the formation and transformation of DBPs in the water distribution system (WDS). The complex environment in WDS will affect the reaction between residual chlorine and organic matter to form new DBPs. This paper provides an overall review of DBPs formation and transformation in the WDS. Firstly, the occurrence of DBPs in the WDS around the world was cataloged. Secondly, the primary factors affecting the formation of DBPs in WDS have also been summarized, including secondary chlorination, pipe materials, biofilm, deposits and coexisting anions. Secondary chlorination and biofilm increased the concentration of regular DBPs (e.g., trihalomethanes (THMs) and haloacetic acids (HAAs)) in the WDS, while Br- and I- increased the formation of brominated DBPs (Br-DBPs) and iodinated DBPs (I-DBPs), respectively. The mechanism of DBPs formation and transformation in the WDS was systematically described. Aromatic DBPs could be directly or indirectly converted to aliphatic DBPs, including ring opening, side chain breaking, chlorination, etc. Finally, the toxicity of drinking water in the WDS caused by DBPs transformation was examined. This review is conducive to improving the knowledge gap about DBPs formation and transformation in WDS to better solve water supply security problems in the future.


Asunto(s)
Desinfectantes , Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Desinfección , Desinfectantes/análisis , Contaminantes Químicos del Agua/análisis , Trihalometanos/análisis , Halogenación , Cloro
19.
Food Chem ; 404(Pt B): 134646, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36283317

RESUMEN

Freezing and thawing are widely used in dairy processing to ensure the continuous supply of raw milk. In virtue of this, the influences of freeze-thaw cycles on physicochemical stability and in vitro digestibility of goat milk were evaluated. Experimental results showed that repeated freeze-thaw cycles led to the increase of acidity and medium-short chain free fatty acids of goat milk, and the significant decrease of fat and apparent viscosity. Furthermore, the degree of protein oxidation was enhanced, and the secondary structure changed to random coil. The particle size distribution and microstructure all showed the aggregation of goat milk droplets, resulting in the decrease of physical stability. Nevertheless, repeated freeze-thaw cycles could enhance the simulated in vitro digestibility and antioxidant capacity of digested products. These results are helpful to evaluate the quality characteristics of raw goat milk and provide theoretical reference for the industrial production of goat milk products.


Asunto(s)
Cabras , Leche , Animales , Congelación
20.
Ultrason Sonochem ; 95: 106369, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36965313

RESUMEN

The purpose of this study was to investigate effect of physical treatment (ultrasound, U/high pressure homogenization, H/combined treatment, UH or HU) and surfactant (Mogroside V, Mog) on air/water interface adsorption and foaming properties of α-lactalbumin (ALa). Firstly, the binding of Mog and all physical-treated ALa was a static quenching process. Mog had the greatest binding affinity for HU-ALa among all treated samples. U or H treatment could change surface hydrophobicity of ALa/Mog complex. Secondly, at the molar ratio (ALa:Mog) of 1:50, foaming ability (FA) of all ALa samples got the maximum. The sequence of FA in ALa and ALa/Mog complex was listed as follow: HU > U > H > UH. Moreover, foaming stability (FS) of HU-ALa was the highest, followed by H-ALa, U-ALa and UH-ALa. Meanwhile, low concentration Mog increased FS of ALa or UH-ALa, but it reduced FS of H-ALa, U-ALa and HU-ALa. Quartz crystal microbalance with dissipation monitoring (QCM-D) experiment indicated that ALa/Mog complex after U or H treatment was quickly absorbed at air/water interface, compared with the treated ALa, and HU-ALa/Mog had the largest frequency shift. In addition, HU-ALa had the thickest bubble membrane and the highest dissipation shift in all samples, indicating that the absorbed membrane thickness and viscoelasticity of samples was correlated with foam stability. Therefore, U and H treatment synergism with Mog was an effective approach to enhance foam properties of ALa, which indicated that HU-treated ALa/Mog complex could be viewed as the safe and efficient foaming agent applied in food processing.


Asunto(s)
Lactalbúmina , Tensoactivos , Lactalbúmina/química , Agua/química
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