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1.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35064080

RESUMO

The phase state of respiratory aerosols and droplets has been linked to the humidity-dependent survival of pathogens such as SARS-CoV-2. To inform strategies to mitigate the spread of infectious disease, it is thus necessary to understand the humidity-dependent phase changes associated with the particles in which pathogens are suspended. Here, we study phase changes of levitated aerosols and droplets composed of model respiratory compounds (salt and protein) and growth media (organic-inorganic mixtures commonly used in studies of pathogen survival) with decreasing relative humidity (RH). Efflorescence was suppressed in many particle compositions and thus unlikely to fully account for the humidity-dependent survival of viruses. Rather, we identify organic-based, semisolid phase states that form under equilibrium conditions at intermediate RH (45 to 80%). A higher-protein content causes particles to exist in a semisolid state under a wider range of RH conditions. Diffusion and, thus, disinfection kinetics are expected to be inhibited in these semisolid states. These observations suggest that organic-based, semisolid states are an important consideration to account for the recovery of virus viability at low RH observed in previous studies. We propose a mechanism in which the semisolid phase shields pathogens from inactivation by hindering the diffusion of solutes. This suggests that the exogenous lifetime of pathogens will depend, in part, on the organic composition of the carrier respiratory particle and thus its origin in the respiratory tract. Furthermore, this work highlights the importance of accounting for spatial heterogeneities and time-dependent changes in the properties of aerosols and droplets undergoing evaporation in studies of pathogen viability.


Assuntos
Cloreto de Cálcio/química , Modelos Químicos , Aerossóis e Gotículas Respiratórios/química , SARS-CoV-2/química , Albumina Sérica/química , Cloreto de Sódio/química , COVID-19/virologia , Difusão , Desinfecção/métodos , Humanos , Umidade , Cinética , Viabilidade Microbiana , Transição de Fase , Propriedades de Superfície
2.
Biomacromolecules ; 25(7): 4469-4481, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38877974

RESUMO

A facile method was proposed for preparing controllable multicompartment gel microcarriers using an aqueous two-phase emulsion system. By leveraging the density difference between the upper polyethylene glycol solution and the lower dextran-calcium chloride (CaCl2) solution in the collection solution and the high viscosity of the lower solution, controllable fusion of core-shell droplets made by coextrusion devices was achieved at the water/water (w/w) interface to fabricate microcarriers with separated core compartments. By adjusting the sodium alginate concentration, collected solution composition, and number of fused liquid droplets, the pore size, shape, and number of compartments could be controlled. Caco-2 and HepG2 cells were encapsulated in different compartments to establish gut-liver coculture models, exhibiting higher viability and proliferation compared to monoculture models. Notably, significant differences in cytokine expression and functional proteins were observed between the coculture and monoculture models. This method provides new possibilities for preparing complex and functional three-dimensional coculture materials.


Assuntos
Alginatos , Técnicas de Cocultura , Emulsões , Humanos , Técnicas de Cocultura/métodos , Células Hep G2 , Emulsões/química , Células CACO-2 , Alginatos/química , Géis/química , Polietilenoglicóis/química , Cloreto de Cálcio/química , Dextranos/química , Proliferação de Células , Sobrevivência Celular
3.
J Sci Food Agric ; 104(9): 5284-5295, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38308594

RESUMO

BACKGROUND: The increasing attention toward frozen soy-based foods has sparked interest. Variations exist in the quality and structure of soymilk gels induced by different salt ions, leading to diverse changes post-freezing. This study compared and analyzed the effects of calcium chloride (CC), magnesium chloride (MC) and calcium sulfate (CS) on the quality characteristics and protein structure changes of soymilk gels (CC-S, MC-S and CS-S) before and after freezing, and clarified the mechanisms of freezing on soymilk gel. RESULTS: The formation rate of soymilk gel is influenced by the type of salt ions. In comparison to CS and MC, soymilk gel induced by CC exhibited the fastest formation rate, highest gel hardness, lowest moisture content, and smaller gel pores. However, freezing treatment deteriorated the quality of soymilk gel induced by different salt ions, leading to a decline in textural properties (hardness and chewiness). Among these, the textual state of CC-induced soymilk gel remained optimal, exhibiting the least apparent damage and minimal cooking loss. Freezing treatments prompt a transition of soymilk gel secondary structure from ß-turns to ß-sheets, disrupting the protein's tertiary structure. Furthermore, freezing treatments also fostered the crosslinking between soymilk gel protein, increasing the content of disulfide bonds. CONCLUSION: The quality of frozen soymilk gel is influenced by the rate of gel formation induced by salt ions. After freezing, soymilk gel with faster gelation rates exhibited a greater tendency for the transformation of protein-water interactions into protein-protein interactions. They showed a higher degree of disulfide bond formation, resulting in a more tightly knit and firm frozen gel network structure with denser and more uniformly distributed pores. © 2024 Society of Chemical Industry.


Assuntos
Congelamento , Géis , Leite de Soja , Leite de Soja/química , Géis/química , Proteínas de Soja/química , Manipulação de Alimentos/métodos , Cloreto de Magnésio/química , Cloreto de Cálcio/química , Íons/química
4.
Molecules ; 28(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38067573

RESUMO

Capsaicin is known as an oily extract of paprika that is characterized by pungent taste and bioactivity. It also may cause irritation to the mouth and stomach which is why is so important to immobilize capsaicin on a carrier to prevent it. The usage of alginate oligomers, which has an antioxidant potential compared to alginate, is of benefit because it may be used in the immobilization of bioactive substances that are fragile to oxidation. The purpose of this study was to use sodium alginate oligomers as a coating material in the encapsulation process of paprika oleoresin. Alginate oligomers were produced by chemical degradation with hydrogen peroxide. The characteristics of the samples were obtained by measuring the viscosity, the contact angle of the surface, and the surface tension of solutions. The obtained solution of alginate oligomers served as the carrier material for the immobilization of capsaicin. Capsules were prepared by ionic gelation using a calcium chloride solution as a crosslinking agent. In this way, capsules without and with the core (capsaicin) were prepared and their ability to scavenge free radicals (DPPH) and iron-reducing properties (FRAP) were determined. The stability of the capsules was examined by thermal decomposition and under conditions of the gastric and small intestine, and capsaicin content was detected using high-performance liquid chromatography. It was found that alginate oligomers could be used in the encapsulation of bioactive compounds and the efficiency was above 80%. Capsule production from alginate oligomers affected their thermal stability. The use of alginate derivatives as a carrier increased the antioxidant properties of the finished product, as well as its ability to reduce iron ions. The use of alginate oligomers as a coating material prevented the active substance from being released too early in the conditions of the small intestine, prolonged the stability of the capsules, and supported their durability in gastric conditions.


Assuntos
Alginatos , Capsicum , Alginatos/química , Capsaicina , Antioxidantes/farmacologia , Antioxidantes/química , Cloreto de Cálcio/química , Ferro , Cápsulas
5.
J Sci Food Agric ; 103(13): 6180-6189, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37139635

RESUMO

BACKGROUND: Plant protein is widely used in the study of animal protein substitutes and healthy sustainable products. The gel properties are crucial for the production of plant protein foods. Therefore, the present study investigated the use of soybean oil to modulate the gel properties of soybean protein isolation-wheat gluten composite with or without CaCl2 . RESULTS: Oil droplets filled protein network pores under the addition of soybean oil (1-2%). This resulted in an enhanced gel hardness and water holding capacity. Further addition of soybean oil (3-4%), oil droplets and some protein-oil compounds increased the distance between the protein molecule chain. The results of Fourier transform infrared spectroscopy and intermolecular interaction also showed that the disulfide bond and ß-sheet ratio decreased in the gel system, which damaged the overall structure of the gel network. Compared with the addition of 0 m CaCl2 , salt ion reduced the electrostatic repulsion between proteins, and local protein cross-linking was more intense at 0.005 m CaCl2 concentration. In the present study, structural properties and rheological analysis showed that the overall strength of the gel was weakened after the addition of CaCl2 . CONCLUSION: The presence of appropriate amount of soybean oil can fill the gel pores and improve the texture properties and network structure of soy protein isolate-wheat gluten (SPI-WG) composite gel. Excessive soybean oil may hinder protein-protein interaction and adversely affect protein gel. In addition, the presence or absence of CaCl2 significantly affected the gelling properties of SPI-WG composite protein gels. © 2023 Society of Chemical Industry.


Assuntos
Óleo de Soja , Proteínas de Soja , Proteínas de Soja/química , Triticum/química , Cloreto de Cálcio/química , Glutens/química , Géis/química
6.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35163203

RESUMO

At present, the use of benzimidazole drugs in veterinary medicine is strongly limited by both pharmacokinetics and formulative issues. In this research, the possibility of applying an innovative semi-solid extrusion 3D printing process in a co-axial configuration was speculated, with the aim of producing a new gastro-retentive dosage form loaded with ricobendazole. To obtain the drug delivery system (DDS), the ionotropic gelation of alginate in combination with a divalent cation during the extrusion was exploited. Two feeds were optimized in accordance with the printing requirements and the drug chemical properties: the crosslinking ink, i.e., a water ethanol mixture containing CaCl2 at two different ratios 0.05 M and 0.1 M, hydroxyethyl cellulose 2% w/v, Tween 85 0.1% v/v and Ricobendazole 5% w/v; and alginate ink, i.e., a sodium alginate solution at 6% w/v. The characterization of the dried DDS obtained from the extrusion of gels containing different amounts of calcium chloride showed a limited effect on the ink extrudability of the crosslinking agent, which on the contrary strongly influenced the final properties of the DDS, with a difference in the polymeric matrix toughness and resulting effects on floating time and drug release.


Assuntos
Albendazol/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Albendazol/administração & dosagem , Albendazol/farmacologia , Alginatos/química , Cloreto de Cálcio/química , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/veterinária , Liberação Controlada de Fármacos , Géis/química , Ácidos Hexurônicos/química , Impressão Tridimensional
7.
Molecules ; 27(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35164413

RESUMO

The sunscreen nanocapsules were successfully synthesized by the way of layer-by-layer self-assembly using charged droplets (prepared by emulsification of LAD-30, Tween-80 and EHA (2-Ethylhexyl-4-dimethylaminobenzoate)) as templates. Chitosan/sodium alginate/calcium chloride were selected as wall materials to wrap EHA. The emulsions with the ratio of Tween-80 to EHA (1:1) were stable. A stable NEI negative emulsion can be obtained when the ratio of Tween-80 and LAD-30 was 9:1. Chitosan solutions (50 kDa, 0.25 mg/mL) and sodium alginate solutions (0.5 mg/mL) were selected to prepare nanocapsules. The nanocapsules were characterized via some physico-chemical methods. Based on the synergistic effects of the electrostatic interaction between wall materials and emulsifiers, EHA was effectively encapsulated. DLS and TEM showed that the sunscreen nanocapsules were dispersed in a spherical shape with nano-size, with the increasing number of assembly layers, the size increased from 155 nm (NEI) to 189 nm (NEII) to 201 nm (NEIII) and 205 nm after solidification. The release studies in vitro showed sustained release behavior of the nanocapsules were observed with the increase of the number of deposition layers, implying a good coating effect. The sunscreen nanocapsules could control less than 50% the release of EHA after crosslinking of calcium chloride and sodium alginate, which also could effectively avoid the stimulation of the sun protection agent on the skin.


Assuntos
Alginatos/química , Cloreto de Cálcio/química , Quitosana/química , Preparações de Ação Retardada/química , Protetores Solares/administração & dosagem , para-Aminobenzoatos/administração & dosagem , Animais , Liberação Controlada de Fármacos , Masculino , Camundongos , Absorção Cutânea , Protetores Solares/farmacocinética , Protetores Solares/farmacologia , para-Aminobenzoatos/farmacocinética , para-Aminobenzoatos/farmacologia
8.
J Sci Food Agric ; 102(1): 425-433, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34143901

RESUMO

BACKGROUND: Apple wine is a popular alcoholic beverage for its nutrition and fresh taste. However, the methanol existing in apple wine restricts its quality. Unfortunately, there are no methods to reduce the methanol content in fruit wine. To this end, bentonite (B), calcium chloride (CC) and their combination (B&CC) were added into apple juice in this study. The treated juice (0) and supernatant obtained by standing the juice at 25 °C for 24 h were fermented at 25 °C and 10 °C, respectively. RESULTS: Bentonite was an excellent methanol interrupter, a pectin retainer and a wine quality defender both at 25 and 10 °C. The lowest methanol content of 1.41 mg L-1 and higher pectin content of 84.74 mg L-1 were reached in the finished wine by B0 at 10 °C. Calcium chloride decreased pectin content, elevated methanol content and changed the profile of individual organic acids. In fact, the wine by B&CC0 at 25 °C showed dramatic changes in individual organic acids. The content of l-malic acid and succinic acid was only 2.22% and 6.29% of the control, respectively, while the lactic acid content was 17.72 times that of the control. CONCLUSIONS: It is suggested that B0 and fermented at 10 °C was the most effective way to decrease methanol content, retain pectin content and defend wine quality. © 2021 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/análise , Bentonita/química , Cloreto de Cálcio/química , Manipulação de Alimentos/métodos , Malus/química , Fermentação , Manipulação de Alimentos/instrumentação , Frutas/química , Metanol/química , Pectinas/química
9.
Methods ; 177: 103-113, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917274

RESUMO

Extracellular vesicles (EVs) are membrane bound vesicles released into the extracellular environment by eukaryotic and prokaryotic cells. EVs are enriched in active biomolecules and they can horizontally transfer cargo to recipient cells. In recent years EVs have demonstrated promising clinical applications due to their theragnostic potential. Although EVs have promising therapeutic potential, there are several challenges associated with using EVs before transition from the laboratory to clinical use. Some of these challenges include issues around low yield, isolation and purification methodologies, and efficient engineering (loading) of EVs with therapeutic cargo. Also, to achieve higher therapeutic efficiency, EV architecture and cargo may need to be manipulated prior to clinical application. Some of these issues have been addressed by developing biomimetic EVs. EV mimetic-nanovesicles (M-NVs) are a type of artificial EVs which can be generated from all cell types with comparable characteristics as EVs for an alternative therapeutic modality. In this review, we will discuss current techniques for modifying EVs and methodology used to generate and customize EV mimetic-nanovesicles.


Assuntos
Bioengenharia/métodos , Diabetes Mellitus/terapia , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Vesículas Extracelulares/metabolismo , Neoplasias/terapia , Sepse/terapia , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Cloreto de Cálcio/química , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Eletroporação/métodos , Vesículas Extracelulares/química , Vesículas Extracelulares/transplante , Expressão Gênica , Humanos , Lipídeos/química , Proteína 2 de Membrana Associada ao Lisossomo/genética , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Proteínas do Leite/genética , Proteínas do Leite/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sepse/genética , Sepse/metabolismo , Sepse/patologia , Sonicação/métodos , Tetraspaninas/genética , Tetraspaninas/metabolismo
10.
Phys Chem Chem Phys ; 23(2): 1706-1717, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33427255

RESUMO

The use of water as a component of deep eutectic systems (DES) has raised some questions regarding its influence on the nature of the mixture. Does it form a DES or an aqueous solution and what is the role of water? In this work, the nature of citric acid:l-arginine:water mixtures was explored through phase equilibria studies and spectroscopic analysis. In a first step, PC-SAFT was validated as a predictive tool to model the water influence on the solid liquid equilibria (SLE) of the DES reline using the individual-component approach. Hence, activity coefficients in the ternary systems citric acid:l-arginine:water and respective binary combinations were studied and compared using ePC-SAFT. It was observed that the water-free mixtures citric acid:l-arginine showed positive deviation from Raoult's law, while upon addition of water strong negative deviation from Raoult's law was found, yielding melting depressions around 100 K. Besides these strong interactions, pH was found to become acidic (pH = 3.5) upon water addition, which yields the formation of charged species ([H2Cit]- and [l-arg]+). Thus, the increased interactions between the molecules upon water addition might be caused by several mechanisms such as hydrogen bonding or ionic forces, both being induced by water. For further investigation, the liquid mixtures citric acid:l-arginine:water were studied by FTIR and NMR spectroscopy. FTIR spectra disproved a possible solubility enhancement caused by salt formation between citric acid and l-arginine, while NMR spectra supported the formation of a hydrogen bonding network different from the binary systems citric acid:water and l-arginine:water. Either being a DES or other type of non-ideal solution, the liquefaction of the studied systems is certainly caused by a water-mediator effect based on the formation of charged species and cross interactions between the mixture constituents.


Assuntos
Arginina/química , Ácido Cítrico/química , Água/química , Cloreto de Cálcio/química , Congelamento , Modelos Químicos , Termodinâmica , Temperatura de Transição , Ureia/química
11.
J Chem Phys ; 154(19): 195103, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34240890

RESUMO

Interactions among ions and their specific interactions with macromolecular solutes are known to play a central role in biomolecular stability. However, similar effects in the conformational stability of protein loops that play functional roles, such as binding ligands, proteins, and DNA/RNA molecules, remain relatively unexplored. A well-characterized enzyme that has such a functional loop is Escherichia coli dihydrofolate reductase (ecDHFR), whose so-called M20 loop has been observed in three ordered conformations in crystal structures. To explore how solution ionic strengths may affect the M20 loop conformation, we proposed a reaction coordinate that could quantitatively describe the loop conformation and used it to classify the loop conformations in representative ecDHFR x-ray structures crystallized in varying ionic strengths. The Protein Data Bank survey indicates that at ionic strengths (I) below the intracellular ion concentration-derived ionic strength in E. coli (I ≤ 0.237M), the ecDHFR M20 loop tends to adopt open/closed conformations, and rarely an occluded loop state, but when I is >0.237M, the loop tends to adopt closed/occluded conformations. Distance-dependent electrostatic potentials around the most mobile M20 loop region from molecular dynamics simulations of ecDHFR in equilibrated CaCl2 solutions of varying ionic strengths show that high ionic strengths (I = 0.75/1.5M) can preferentially stabilize the loop in closed/occluded conformations. These results nicely correlate with conformations derived from ecDHFR structures crystallized in varying ionic strengths. Altogether, our results suggest caution in linking M20 loop conformations derived from crystal structures solved at ionic strengths beyond that tolerated by E. coli to the ecDHFR function.


Assuntos
Cloreto de Cálcio/química , Escherichia coli/enzimologia , Tetra-Hidrofolato Desidrogenase/química , Simulação de Dinâmica Molecular , Concentração Osmolar , Conformação Proteica , Soluções , Tetra-Hidrofolato Desidrogenase/metabolismo
12.
J Nanobiotechnology ; 19(1): 417, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903236

RESUMO

Clinically, steroid-resistant nephrotic syndrome (SRNS) is always prolonged and difficult to treat and easily develops into end-stage renal disease, resulting in a low survival rate. Strategies to reverse steroid resistance and reduce the long-term use of high doses of steroid medicines are urgently needed. In this study, a novel nanoparticle drug system (Pm-GCH) with a core-shell structure was designed. Metal-organic frameworks, synthesized by glycyrrhizic acid (G) and calcium ions (Ca2+) loaded with hydrocortisone (H) were the core of the nanoparticles. Platelet membrane vesicles were the shells. The natural platelet membrane endows Pm-GCH with good biocompatibility and the ability to promote immune escape. In addition, under the chemotaxis of inflammatory factors, platelet membranes assist Pm-GCH in nonspecific targeting of the inflammatory sites of the kidney. Under an inflammatory acid environment, GCH slowly degrades and releases glycyrrhizic acid and hydrocortisone. Glycyrrhizic acid inhibits the inactivation of hydrocortisone, jointly inhibits the activity of phospholipase A2 (PLA2) and the classic activation pathway of complement C2, blocks the production of inflammatory factors, plays an anti-inflammatory role, and enhances the efficacy of hydrocortisone in the treatment of SRNS. Moreover, glycyrrhizic acid alleviates osteoporosis induced by long-term use of glucocorticoids. These results indicate that Pm-GCH is a promising treatment strategy for SRNS.


Assuntos
Anti-Inflamatórios , Materiais Biomiméticos , Osso e Ossos/efeitos dos fármacos , Nanomedicina , Síndrome Nefrótica/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Cloreto de Cálcio/química , Cloreto de Cálcio/metabolismo , Resistência a Medicamentos , Feminino , Ácido Glicirrízico/química , Ácido Glicirrízico/metabolismo , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Camundongos , Osteoporose/metabolismo
13.
Pharmacology ; 106(11-12): 687-692, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34662883

RESUMO

Preparation of brain microsomes by the calcium chloride aggregation method has been suggested as an alternative to the ultracentrifugation method. However, the effects of the calcium chloride concentration on the quality of the microsomal fractions are not known. Brain microsomes were prepared from the adult rat brains using the high-speed ultracentrifugation and low-speed calcium chloride (10-100 mM) aggregation methods (n = 5-6 per group). The microsomal protein yield (spectrometry), the cytochrome P450 reductase (CPR) activity (spectrometry), and the monooxygenase activities (UPLC-MS/MS) of CYP2D and CYP2E1 were determined in the obtained fractions. Increasing the concentrations of calcium chloride progressively increased the protein yield of the low-speed microsomal fractions. However, the increased yield was associated with a significant decrease in the activities of CPR, CYP2D, and CYP2E1. Additionally, the CYP2D and CYP2E1 activities were significantly correlated with the CPR activities of the fractions. In conclusion, when an ultracentrifuge is available, preparation of brain microsomes by the ultracentrifugation method might be preferable. However, the calcium aggregation method at a calcium chloride concentration of 10 mM is an acceptable alternative to the ultracentrifuge method.


Assuntos
Encéfalo/metabolismo , Cloreto de Cálcio/química , Microssomos/metabolismo , Animais , Citocromo P-450 CYP2E1/metabolismo , Relação Dose-Resposta a Droga , Oxigenases de Função Mista/metabolismo , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Ratos , Ultracentrifugação
14.
Chem Soc Rev ; 49(13): 4273-4306, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32453311

RESUMO

Furans represent one of the most important classes of intermediates in the conversion of non-edible lignocellulosic biomass into bio-based chemicals and fuels. At present, bio-furan derivatives are generally obtained from cellulose and hemicellulose fractions of biomass via the acid-catalyzed dehydration of their relative C6-C5 sugars and then converted into a wide range of products. Furfural (FUR) and 5-hydroxymethylfurfural (HMF) are surely the most used furan-based feedstocks since their chemical structure allows the preparation of various high-value-added chemicals. Among several well-established catalytic approaches, hydrogenation and oxygenation processes have been efficiently adopted for upgrading furans; however, harsh reaction conditions are generally required. In this review, we aim to discuss the conversion of biomass derived FUR and HMF through unconventional (transfer hydrogenation, photocatalytic and electrocatalytic) catalytic processes promoted by heterogeneous catalytic systems. The reaction conditions adopted, the chemical nature and the physico-chemical properties of the most employed heterogeneous systems in enhancing the catalytic activity and in driving the selectivity to desired products are presented and compared. At the same time, the latest results in the production of FUR and HMF through novel environmental friendly processes starting from lignocellulose as well as from wastes and by-products obtained in the processing of biomass are also overviewed.


Assuntos
Furaldeído/análogos & derivados , Furaldeído/química , Biomassa , Cloreto de Cálcio/química , Catálise , Celulose/química , Técnicas Eletroquímicas , Hidrogenação , Lignina/química , Metais/química , Oxirredução , Óxidos/química , Processos Fotoquímicos , Polissacarídeos/química , Especificidade por Substrato , Xilose/química , Zeolitas/química
15.
J Microencapsul ; 38(1): 22-35, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33047995

RESUMO

Traditional level of fertilisers was used by most farmers in China with the risks about resources wasting, environmental pollution together with soil structure deterioration. It is practicable to tackle the challenges about over-fertilisation and low efficiency with microencapsulated soil conditioner (MSC), which clads the water soluble core with natural polymer. Fulvic acid (FA) can be used as core material, because it possesses the characteristics of water-soluble, fertiliser maintenance and expedient monitoring. The morphology, structure, and properties of MSC were studied and compared. The particle size of MSC was ranged from 1.58 to 2.14 mm with a similar shape which was obtained by conventional measuring method due to their soft features. This was mainly attributed to the concentration of liquid paraffin and the interaction between shell materials and calcium chloride. FTIR spectra showed that a peak appeared at 1372 cm-1, and this was ascribed to the microcapsules crosslinked and solidified by calcium ions. Sustained release experiment revealed that the microcapsules owned better fertiliser-retaining and water-retaining performances, and FA may be released as long as 750 h. Biodegradation experiments revealed that an obvious pore structure was found on the surface of microspheres after 30 d of degradation, and this was consistent with the sustained release experiment. Pot experiment illustrated that the plants cured with the microcapsules showed significant growth trend and grew up to 9.2 cm with a maximum rate, and this revealed that MSC owned better performance of promoting the growth of crop root.


Assuntos
Agricultura/instrumentação , Raízes de Plantas/metabolismo , Água/química , Adsorção , Biodegradação Ambiental , Cloreto de Cálcio/química , Cápsulas , Produtos Agrícolas , Reagentes de Ligações Cruzadas , Microesferas , Tamanho da Partícula , Salinidade , Solo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
16.
Int J Mol Sci ; 23(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35008694

RESUMO

The objective of this study was to produce bactericidal polymer films containing birch tar (BT). The produced polymer films contain PLA, plasticiser PEG (5% wt.) and birch tar (1, 5 and 10% wt.). Compared to plasticised PLA, films with BT were characterised by reduced elongation at break and reduced water vapour permeability, which was the lowest in the case of film with 10% wt. BT content. Changes in the morphology of the produced materials were observed by performing scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis; the addition of BT caused the surface of the film to be non-uniform and to contain recesses. FTIR analysis of plasticised PLA/BT films showed that the addition of birch tar did not change the crystallinity of the obtained materials. According to ISO 22196: 2011, the PLA film with 10% wt. BT content showed the highest antibacterial effect against the plant pathogens A. tumefaciens, X. campestris, P. brassicacearum, P. corrugata, P. syringae. It was found that the introduction of birch tar to plasticised PLA leads to a material with biocidal effect and favourable physicochemical and structural properties, which classifies this material for agricultural and horticultural applications.


Assuntos
Betula/química , Fenômenos Químicos , Desinfetantes/farmacologia , Poliésteres/farmacologia , Alcatrões/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cloreto de Cálcio/química , Testes de Sensibilidade Microbiana , Permeabilidade , Plásticos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Propriedades de Superfície
17.
Int J Mol Sci ; 22(4)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669209

RESUMO

Nisin Z, an amphipathic peptide, with a significant antibacterial activity against Gram-positive bacteria and low toxicity in humans, has been studied for food preservation applications. Thus far, very little research has been done to explore its potential in biomedicine. Here, we report the modification of sodium alginate (SA) and gelatin (GN) blended microfibers, produced via the wet-spinning technique, with Nisin Z, with the purpose of eradicating Staphylococcus aureus-induced infections. Wet-spun SAGN microfibers were successfully produced at a 70/30% v/v of SA (2 wt%)/GN (1 wt%) polymer ratio by extrusion within a calcium chloride (CaCl2) coagulation bath. Modifications to the biodegradable fibers' chemical stability and structure were then introduced via crosslinking with CaCl2 and glutaraldehyde (SAGNCL). Regardless of the chemical modification employed, all microfibers were labelled as homogeneous both in size (≈246.79 µm) and shape (cylindrical and defect-free). SA-free microfibers, with an increased surface area for peptide immobilization, originated from the action of phosphate buffer saline solution on SAGN fibers, were also produced (GNCL). Their durability in physiological conditions (simulated body fluid) was, however, compromised very early in the experiment (day 1 and 3, with and without Nisin Z, respectively). Only the crosslinked SAGNCL fibers remained intact for the 28 day-testing period. Their thermal resilience in comparison with the unmodified and SA-free fibers was also demonstrated. Nisin Z was functionalized onto the unmodified and chemically altered fibers at an average concentration of 178 µg/mL. Nisin Z did not impact on the fiber's morphology nor on their chemical/thermal stability. However, the peptide improved the SA fibers (control) structural integrity, guaranteeing its stability for longer, in physiological conditions. Its main effect was detected on the time-kill kinetics of the bacteria S. aureus. SAGNCL and GNCL loaded with Nisin Z were capable of progressively eliminating the bacteria, reaching an inhibition superior to 99% after 24 h of culture. The peptide-modified SA and SAGN were not as effective, losing their antimicrobial action after 6 h of incubation. Bacteria elimination was consistent with the release kinetics of Nisin Z from the fibers. In general, data revealed the increased potential and durable effect of Nisin Z (significantly superior to its free, unloaded form) against S. aureus-induced infections, while loaded onto prospective biomedical wet-spun scaffolds.


Assuntos
Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Reagentes de Ligações Cruzadas/química , Gelatina/química , Nisina/análogos & derivados , Staphylococcus aureus/efeitos dos fármacos , Materiais Biocompatíveis/química , Plásticos Biodegradáveis/química , Biopolímeros/química , Cloreto de Cálcio/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Glutaral/química , Cinética , Testes de Sensibilidade Microbiana , Nisina/química , Nisina/farmacologia , Porosidade , Solubilidade , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Água/química
18.
Int J Mol Sci ; 22(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34830334

RESUMO

An association between high serum calcium/phosphate and cardiovascular events or death is well-established. However, a mechanistic explanation of this correlation is lacking. Here, we examined the role of calciprotein particles (CPPs), nanoscale bodies forming in the human blood upon its supersaturation with calcium and phosphate, in cardiovascular disease. The serum of patients with coronary artery disease or cerebrovascular disease displayed an increased propensity to form CPPs in combination with elevated ionised calcium as well as reduced albumin levels, altogether indicative of reduced Ca2+-binding capacity. Intravenous administration of CPPs to normolipidemic and normotensive Wistar rats provoked intimal hyperplasia and adventitial/perivascular inflammation in both balloon-injured and intact aortas in the absence of other cardiovascular risk factors. Upon the addition to primary human arterial endothelial cells, CPPs induced lysosome-dependent cell death, promoted the release of pro-inflammatory cytokines, stimulated leukocyte adhesion, and triggered endothelial-to-mesenchymal transition. We concluded that CPPs, which are formed in the blood as a result of altered mineral homeostasis, cause endothelial dysfunction and vascular inflammation, thereby contributing to the development of cardiovascular disease.


Assuntos
Angina Pectoris/fisiopatologia , Isquemia Encefálica/fisiopatologia , Cloreto de Cálcio/sangue , Doença da Artéria Coronariana/fisiopatologia , Células Endoteliais/patologia , Infarto do Miocárdio/fisiopatologia , Fosfatos/sangue , Angina Pectoris/sangue , Angina Pectoris/genética , Animais , Aorta/metabolismo , Aorta/patologia , Isquemia Encefálica/sangue , Isquemia Encefálica/genética , Cloreto de Cálcio/química , Estudos de Casos e Controles , Morte Celular , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/genética , Células Endoteliais/metabolismo , Transição Epitelial-Mesenquimal , Floculação , Regulação da Expressão Gênica , Humanos , Inflamação , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/metabolismo , Leucócitos/patologia , Lisossomos/metabolismo , Lisossomos/patologia , Masculino , Infarto do Miocárdio/sangue , Infarto do Miocárdio/genética , Fosfatos/química , Cultura Primária de Células , Ratos , Ratos Wistar , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
19.
Molecules ; 26(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670610

RESUMO

This paper presents a facile and low-cost strategy for fabrication lysozyme-loaded mesoporous silica nanotubes (MSNTs) by using silk fibroin (SF) nanofiber templates. The "top-down method" was adopted to dissolve degummed silk in CaCl2/ formic acid (FA) solvent, and the solution containing SF nanofibrils was used for electrospinning to prepare SF nanofiber templates. As SF contains a large number of -OH, -NH2 and -COOH groups, the silica layer could be easily formed on its surface by the Söber sol-gel method without adding any surfactant or coupling agent. After calcination, the MSNTs were obtained with inner diameters about 200 nm, the wall thickness ranges from 37 ± 2 nm to 66 ± 3 nm and the Brunauer-Emmett-Teller (BET) specific surface area was up to 200.48 m2/g, the pore volume was 1.109 cm3/g. By loading lysozyme, the MSNTs exhibited relatively high drug encapsulation efficiency up to 31.82% and an excellent long-term sustained release in 360 h (15 days). These results suggest that the MSNTs with the hierarchical structure of mesoporous and macroporous will be a promising carrier for applications in biomacromolecular drug delivery systems.


Assuntos
Fibroínas/química , Muramidase/metabolismo , Nanofibras/química , Nanotubos/química , Dióxido de Silício/química , Cloreto de Cálcio/química , Liberação Controlada de Fármacos , Formiatos/química , Nanofibras/ultraestrutura , Nanotubos/ultraestrutura , Porosidade , Silanos/química , Soluções , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Viscosidade
20.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071404

RESUMO

Broccoli microgreens have shown potential health benefits due to their high glucosinolate (GL) levels. Previously, we observed that postharvest UVB treatment did not have much effect on increasing GLs in broccoli microgreens. In this study, we investigated the influence of preharvest UVB irradiation on GL levels in broccoli microgreens. UHPLC-ESI/ITMS analysis showed that preharvest UVB treatments with UVB 0.09 and 0.27 Wh/m2 significantly increased the glucoraphanin (GLR), glucoerucin (GLE), and total aliphatic GL levels by 13.7 and 16.9%, respectively, in broccoli microgreens when measured on harvest day. The nutritional qualities of UVB-treated microgreens were stable during 21-day storage, with only small changes in their GL levels. Broccoli microgreens treated before harvest with UVB 0.27 Wh/m2 and 10 mM CaCl2 spray maintained their overall quality, and had the lowest tissue electrolyte leakage and off-odor values during the storage. Furthermore, preharvest UVB 0.27 Wh/m2 treatment significantly increased GL biosynthesis genes when evaluated before harvest, and reduced the expression level of myrosinase, a gene responsible for GL breakdown during postharvest storage. Overall, preharvest UVB treatment, together with calcium chloride spray, can increase and maintain health-beneficial compound levels such as GLs and prolong the postharvest quality of broccoli microgreens.


Assuntos
Brassica/metabolismo , Glucosinolatos/química , Raios Ultravioleta , Antioxidantes/química , Cálcio/química , Cloreto de Cálcio/química , Cromatografia Líquida de Alta Pressão , Glucose/análogos & derivados , Glucose/química , Imidoésteres/química , Valor Nutritivo , Estresse Oxidativo , Oximas/química , Fenol , Sementes , Espectrometria de Massas por Ionização por Electrospray , Sulfóxidos/química
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