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1.
Biomolecules ; 11(3)2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810129

RESUMO

Global processes, such as climate change, frequent and distant travelling and population growth, increase the risk of viral infection spread. Unfortunately, the number of effective and accessible medicines for the prevention and treatment of these infections is limited. Therefore, in recent years, efforts have been intensified to develop new antiviral medicines or vaccines. In this review article, the structure and activity of the most promising antiviral cyanobacterial products are presented. The antiviral cyanometabolites are mainly active against the human immunodeficiency virus (HIV) and other enveloped viruses such as herpes simplex virus (HSV), Ebola or the influenza viruses. The majority of the metabolites are classified as lectins, monomeric or dimeric proteins with unique amino acid sequences. They all show activity at the nanomolar range but differ in carbohydrate specificity and recognize a different epitope on high mannose oligosaccharides. The cyanobacterial lectins include cyanovirin-N (CV-N), scytovirin (SVN), microvirin (MVN), Microcystisviridis lectin (MVL), and Oscillatoria agardhii agglutinin (OAA). Cyanobacterial polysaccharides, peptides, and other metabolites also have potential to be used as antiviral drugs. The sulfated polysaccharide, calcium spirulan (CA-SP), inhibited infection by enveloped viruses, stimulated the immune system's response, and showed antitumor activity. Microginins, the linear peptides, inhibit angiotensin-converting enzyme (ACE), therefore, their use in the treatment of COVID-19 patients with injury of the ACE2 expressing organs is considered. In addition, many cyanobacterial extracts were revealed to have antiviral activities, but the active agents have not been identified. This fact provides a good basis for further studies on the therapeutic potential of these microorganisms.


Assuntos
Antivirais/química , Cianobactérias/química , HIV/efeitos dos fármacos , Lectinas/farmacologia , Polissacarídeos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Simplexvirus/efeitos dos fármacos , Fármacos Anti-HIV/farmacologia , Antineoplásicos/farmacologia , Antivirais/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , COVID-19/tratamento farmacológico , Carboidratos/química , Carboidratos/farmacologia , Cianobactérias/metabolismo , Infecções por HIV/tratamento farmacológico , Humanos , Lectinas/química , Lectinas/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo
2.
Sci Rep ; 11(1): 7880, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846482

RESUMO

Since the pandemic outbreak of Covid-19 in December 2019, several lateral flow assay (LFA) devices were developed to enable the constant monitoring of regional and global infection processes. Additionally, innumerable lateral flow test devices are frequently used for determination of different clinical parameters, food safety, and environmental factors. Since common LFAs rely on non-biodegradable nitrocellulose membranes, we focused on their replacement by cellulose-composed, biodegradable papers. We report the development of cellulose paper-based lateral flow immunoassays using a carbohydrate-binding module-fused to detection antibodies. Studies regarding the protein binding capacity and potential protein wash-off effects on cellulose paper demonstrated a 2.7-fold protein binding capacity of CBM-fused antibody fragments compared to the sole antibody fragment. Furthermore, this strategy improved the spatial retention of CBM-fused detection antibodies to the test area, which resulted in an enhanced sensitivity and improved overall LFA-performance compared to the naked detection antibody. CBM-assisted antibodies were validated by implementation into two model lateral flow test devices (pregnancy detection and the detection of SARS-CoV-2 specific antibodies). The CBM-assisted pregnancy LFA demonstrated sensitive detection of human gonadotropin (hCG) in synthetic urine and the CBM-assisted Covid-19 antibody LFA was able to detect SARS-CoV-2 specific antibodies present in serum. Our findings pave the way to the more frequent use of cellulose-based papers instead of nitrocellulose in LFA devices and thus potentially improve the sustainability in the field of POC diagnostics.


Assuntos
Anticorpos Antivirais/análise , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Carboidratos/química , Colódio/química , Imunoensaio/métodos , Materiais Biocompatíveis , Gonadotropina Coriônica/química , Clostridium thermocellum/imunologia , Humanos , Fragmentos de Imunoglobulinas/química , Imunoglobulina G/química , Sistemas Automatizados de Assistência Junto ao Leito , Ligação Proteica , SARS-CoV-2/imunologia , Urinálise
3.
J Med Chem ; 64(9): 6059-6069, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33909975

RESUMO

Shiga toxin is an AB5 toxin produced by Shigella species, while related toxins are produced by Shiga toxin-producing Escherichia coli (STEC). Infection by Shigella can lead to bloody diarrhea followed by the often fatal hemolytic uremic syndrome (HUS). In the present paper, we aimed for a simple and effective toxin inhibitor by comparing three classes of carbohydrate-based inhibitors: glycodendrimers, glycopolymers, and oligosaccharides. We observed a clear enhancement in potency for multivalent inhibitors, with the divalent and tetravalent compounds inhibiting in the millimolar and micromolar range, respectively. However, the polymeric inhibitor based on galabiose was the most potent in the series exhibiting nanomolar inhibition. Alginate and chitosan oligosaccharides also inhibit Shiga toxin and may be used as a prophylactic drug during shigella outbreaks.


Assuntos
Carboidratos/química , Carboidratos/farmacologia , Descoberta de Drogas , Toxina Shiga/antagonistas & inibidores
4.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921945

RESUMO

Glycodendrimers have attracted considerable interest in the field of dendrimer sciences owing to their plethora of implications in biomedical applications. This is primarily due to the fact that cell surfaces expose a wide range of highly diversified glycan architectures varying by the nature of the sugars, their number, and their natural multiantennary structures. This particular situation has led to cancer cell metastasis, pathogen recognition and adhesion, and immune cell communications that are implicated in vaccine development. The diverse nature and complexity of multivalent carbohydrate-protein interactions have been the impetus toward the syntheses of glycodendrimers. Since their inception in 1993, chemical strategies toward glycodendrimers have constantly evolved into highly sophisticated methodologies. This review constitutes the first part of a series of papers dedicated to the design, synthesis, and biological applications of heterofunctional glycodendrimers. Herein, we highlight the most common synthetic approaches toward these complex molecular architectures and present modern applications in nanomolecular therapeutics and synthetic vaccines.


Assuntos
Técnicas de Química Sintética , Dendrímeros/química , Dendrímeros/farmacologia , Desenho de Fármacos , Glicoconjugados/química , Glicoconjugados/farmacologia , Carboidratos/química , Dendrímeros/síntese química , Desenvolvimento de Medicamentos , Glicoconjugados/síntese química , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Terapia de Alvo Molecular , Relação Estrutura-Atividade
5.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922318

RESUMO

This review is written amid a marked progress in the calculation of NMR parameters of carbohydrates substantiated by a vast amount of experimental data coming from several laboratories worldwide. By no means are we trying to cover in the present compilation a huge amount of all available data. The main idea of the present review was only to outline general trends and perspectives in this dynamically developing area on the background of a marked progress in theoretical and computational NMR. Presented material is arranged in three basic sections: (1)-a brief theoretical introduction; (2)-applications and perspectives in computational NMR of monosaccharides; and (3)-calculation of NMR chemical shifts and spin-spin coupling constants of di- and polysaccharides.


Assuntos
Carboidratos/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Algoritmos , Teoria da Densidade Funcional , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Conformação Molecular , Estrutura Molecular , Monossacarídeos/química , Polissacarídeos/química , Solventes
6.
Molecules ; 26(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802601

RESUMO

Annually, millions of tons of foods are generated with the purpose to feed the growing world population. One particular eatable is orange, the production of which in 2018 was 75.54 Mt. One way to valorize the orange residue is to produce bioethanol by fermenting the reducing sugars generated from orange peel. Hence, the objective of the present work was to determine the experimental conditions to obtain the maximum yield of reducing sugars from orange peel using a diluted acid hydrolysis process. A proximate and chemical analysis of the orange peel were conducted. For the hydrolysis, two factorial designs were prepared to measure the glucose and fructose concentration with the 3,5-DNS acid method and UV-Visible spectroscopy. The factors were acid concentration, temperature and hydrolysis time. After the hydrolysis, the orange peel samples were subjected to an elemental SEM-EDS analysis. The results for the orange peel were 73.530% of moisture, 99.261% of volatiles, 0.052% of ash, 0.687% of fixed carbon, 19.801% of lignin, 69.096% of cellulose and 9.015% of hemicellulose. The highest concentration of glucose and fructose were 24.585 and 9.709 g/L, respectively. The results highlight that sugar production is increased by decreasing the acid concentration.


Assuntos
Carboidratos/química , Citrus sinensis/metabolismo , Resíduos/análise , Carboidratos/isolamento & purificação , Citrus sinensis/química , Fermentação , Hidrólise , Temperatura
7.
Molecules ; 26(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557184

RESUMO

Stereoselective reactions of singlet oxygen are of current interest. Since enantioselective photooxygenations have not been realized efficiently, auxiliary control is an attractive alternative. However, the obtained peroxides are often too labile for isolation or further transformations into enantiomerically pure products. Herein, we describe the oxidation of naphthalenes by singlet oxygen, where the face selectivity is controlled by carbohydrates for the first time. The synthesis of the precursors is easily achieved starting from naphthoquinone and a protected glucose derivative in only two steps. Photooxygenations proceed smoothly at low temperature, and we detected the corresponding endoperoxides as sole products by NMR. They are labile and can thermally react back to the parent naphthalenes and singlet oxygen. However, we could isolate and characterize two enantiomerically pure peroxides, which are sufficiently stable at room temperature. An interesting influence of substituents on the stereoselectivities of the photooxygenations has been found, ranging from 51:49 to up to 91:9 dr (diastereomeric ratio). We explain this by a hindered rotation of the carbohydrate substituents, substantiated by a combination of NOESY measurements and theoretical calculations. Finally, we could transfer the chiral information from a pure endoperoxide to an epoxide, which was isolated after cleavage of the sugar chiral auxiliary in enantiomerically pure form.


Assuntos
Carboidratos/química , Naftalenos/química , Oxigênio Singlete/química , Reação de Cicloadição , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
8.
Carbohydr Polym ; 258: 117672, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33593549

RESUMO

Glycans and glycoconjugates in nature include macromolecules with important biological activities and widely distributed in all living organisms. These oligosaccharides and polysaccharides play important roles in a variety of normal physiological and pathological processes, such as cell metastasis, signal transduction, intercellular adhesion, inflammation, and immune response. However, the heterogeneity of naturally occurring glycans and glycoconjugates complicates detailed structure-activity relationship studies resulting in an incomplete understanding of their mechanisms of action and hindering further applications. Therefore, the synthesis of homogeneous, or nearly homogeneous, structurally defined glycans is of great significance for the development of carbohydrate-based drugs. One-pot synthesis represents the fastest strategy to assemble oligosaccharides and polysaccharides, although unfortunately, typically relies on random assembly. In this review, we examine the progress that has been made in the controlled one-pot synthesis of homogeneous or nearly homogeneous oligosaccharides and polysaccharides providing a broad spectrum of options to access size-controlled glycan products.


Assuntos
Carboidratos/química , Química Farmacêutica/tendências , Glicoconjugados/química , Oligossacarídeos/química , Polissacarídeos/química , Sequência de Carboidratos , Técnicas de Química Sintética , Química Farmacêutica/métodos , Glicosilação , Humanos , Inflamação , Metástase Neoplásica , Tamanho da Partícula , Polímeros
9.
Carbohydr Polym ; 258: 117708, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33593577

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are attracting much attention for their potential application in biodegradation. However, there are limited studies on the characterization of the AA11 family. Here, a novel AA11 family protein, TgAA11, from Trichoderma guizhouense NJAU 4742 was characterized, and the isothermal titration calorimetry (ITC) analysis results showed that it exhibited tight binding capacity for copper ions with a Kd value of 4.83 ± 0.79 µM. The MALDI-TOF-MS analysis results indicated that TgAA11 could act on ß-chitin to form C1 oxidation products, and some deacetylated chitooligosaccharides. In addition, the degradation of α-chitin and ß-chitin by a chitinolytic enzyme Sg-chi was substantially increased in the presence of TgAA11 by 39.9 % and 288.2 %, respectively. Furthermore, the active site residues predicted showed that His61 and Tyr142 might be critical for the active site residues of the TgAA11 protein. This study will contribute to the understanding of the function of AA11 LPMOs in the degradation of chitin.


Assuntos
Quitina/química , Cobre/química , Hypocreales/enzimologia , Oxigenases de Função Mista/química , Oxigênio/química , Polissacarídeos/química , Animais , Calorimetria , Carboidratos/química , Domínio Catalítico , Quitina/análogos & derivados , Decapodiformes , Espectroscopia de Ressonância de Spin Eletrônica , Ligação de Hidrogênio , Íons , Cinética , Modelos Moleculares , Filogenia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato
10.
Viruses ; 13(2)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540713

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally. Although measures to control SARS-CoV-2, namely, vaccination, medication, and chemical disinfectants are being investigated, there is an increase in the demand for auxiliary antiviral approaches using natural compounds. Here we have focused on hydroxytyrosol (HT)-rich aqueous olive pulp extract (HIDROX®) and evaluated its SARS-CoV-2-inactivating activity in vitro. We showed that the HIDROX solution exhibits time- and concentration-dependent SARS-CoV-2-inactivating activities, and that HIDROX has more potent virucidal activity than pure HT. The evaluation of the mechanism of action suggested that both HIDROX and HT induced structural changes in SARS-CoV-2, which changed the molecular weight of the spike proteins. Even though the spike protein is highly glycosylated, this change was induced regardless of the glycosylation status. In addition, HIDROX or HT treatment disrupted the viral genome. Moreover, the HIDROX-containing cream applied on film showed time- and concentration-dependent SARS-CoV-2-inactivating activities. Thus, the HIDROX-containing cream can be applied topically as an antiviral hand cream. Our findings suggest that HIDROX contributes to improving SARS-CoV-2 control measures.


Assuntos
Antivirais/farmacologia , Olea , Álcool Feniletílico/análogos & derivados , Extratos Vegetais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Administração Tópica , Animais , Antivirais/química , Carboidratos/química , Chlorocebus aethiops , Proteínas do Nucleocapsídeo de Coronavírus/química , Genoma Viral/efeitos dos fármacos , Glicosilação , Testes de Sensibilidade Microbiana , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/farmacologia , Fosfoproteínas/química , Extratos Vegetais/química , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Creme para a Pele , Glicoproteína da Espícula de Coronavírus/química , Células Vero , Inativação de Vírus/efeitos dos fármacos
11.
Int J Biol Macromol ; 170: 602-621, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387545

RESUMO

There has been a surge in the use of transdermal drug delivery systems (TDDS) for the past few years. The market of TDDS is expected to reach USD 7.1 billion by 2023, from USD 5.7 billion in 2018, at a CAGR of 4.5%. Microneedles (MNs) are a novel class of TDDS with advantages of reduced pain, low infection risk, ease of application, controlled release of therapeutic agents, and enhanced bioavailability. Biodegradable MNs fabricated from natural polymers have become the center of attention among formulation scientists because of their recognized biodegradability, biocompatibility, ease of fabrication, and sustainable character. In this review, we summarize the various polysaccharides and polypeptide based biomaterials that are used to fabricate biodegradable MNs. Particular emphasis is given to cellulose and its derivatives, starch, and complex carbohydrate polymers such as alginates, chitosan, chondroitin sulfate, xanthan gum, pullulan, and hyaluronic acid. Additionally, novel protein-based polymers such as zein, collagen, gelatin, fish scale and silk fibroin (polyamino acid) biopolymers application in transdermal drug delivery have also been discussed. The current review will provide a unique perspective to the readers on the developments of biodegradable MNs composed of carbohydrates and protein polymers with their clinical applications and patent status.


Assuntos
Materiais Biocompatíveis/química , Carboidratos/química , Preparações Farmacêuticas/química , Proteínas/química , Administração Cutânea , Animais , Sistemas de Liberação de Medicamentos/métodos , Humanos , Agulhas
12.
Int J Mol Sci ; 22(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499178

RESUMO

Previously, we isolated jacalin-related lectins termed PPL2, PPL3 (PPL3A, 3B and 3C) and PPL4 from the mantle secretory fluid of Pteria penguin (Mabe) pearl shell. They showed the sequence homology with the plant lectin family, jacalin-related ß-prism fold lectins (JRLs). While PPL3s and PPL4 shared only 35%-50% homology to PPL2A, respectively, they exhibited unique carbohydrate binding properties based on the multiple glycan-binding profiling data sets from frontal affinity chromatography analysis. In this paper, we investigated biomineralization properties of these lectins and compared their biomineral functions. It was found that these lectins showed different effects on CaCO3 crystalization, respectively, although PPL3 and PPL2A showed similar carbohydrate binding specificities. PPL3 suppressed the crystal growth of CaCO3 calcite, while PPL2A increased the number of contact polycrystalline calcite composed of more than one crystal with various orientations. Furthermore, PPL4 alone showed no effect on CaCO3 crystalization; however, PPL4 regulated the size of crystals collaborated with N-acetyl-D-glucosamine and chitin oligomer, which are specific in recognizing carbohydrates for PPL4. These observations highlight the unique functions and molecular evolution of this lectin family involved in the mollusk shell formation.


Assuntos
Exoesqueleto/química , Biomineralização , Bivalves/fisiologia , Carbonato de Cálcio/química , Lectinas/química , Lectinas de Plantas/química , Aminoácidos/química , Animais , Carboidratos/química , Quitina/química , Cristalização , Fenótipo , Isoformas de Proteínas
13.
Carbohydr Polym ; 256: 117414, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483009

RESUMO

The major role of biomolecules in treatment of different diseases has been proven by several studies. However, the main drawback in successful treatment by these molecules is designing of efficient delivery systems to fulfill all of the delivery purposes. In this regard, many polymeric vehicles have been introduced for protecting and delivery of biomolecules to the target site. Chitosan as a unique biopolymer with special properties has been widely used for biomolecule delivery. Several research groups have focused on developing and applying of chitosan as a versatile machine in biomolecule delivery. In this review the unique properties of chitosan have been discussed at first and then its application as a delivery machine for different types of biomolecules include protein and peptides, nucleic acids and vaccines has been considered. Furthermore, the targeting approach by conjugation of various ligands to the chitosan and also the current challenges for development of chitosan vehicles will be discussed for biomolecule delivery.


Assuntos
Biopolímeros/química , Quitosana/química , Portadores de Fármacos , Polímeros/química , Vacinas/química , Animais , Carboidratos/química , Humanos , Insulina/química , Ligantes , Camundongos , Nanopartículas/química , Ácido Oleico/química , Peptídeos/química , Poliésteres/química , Polietilenoglicóis/química , Ratos , Zinco/química
14.
Carbohydr Polym ; 256: 117498, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483025

RESUMO

The present work describes the synthesis of a new series of chitosan-gold hybrid nanoparticles (CS-AuNPs) for the delivery of Punicagranatum L. extract (PE). It proposes CS and PE as reducing agents for gold ions in aqueous solution. The effect of PE on the physicochemical properties of the CS-AuNPs was investigated with UV spectroscopy, DLS, DSC, XRD, FTIR, SEM/EDX and TEM. Interestingly, about 50 % reduction in size was observed with using PE alone for gold reduction. The ζ-potential of CS-AuNPs was shifted from +53.1 ± 6.7 mV to 31.0 ± 6.0 mV upon conjugation of the negatively-charged PE polyphenols. The developed PE-conjugated CS-AuNPs exhibited higher stability at different pH values. About 87 % of the loaded PE was released from the NPs over 24 h. The antibacterial activity of CS-PE-AuNPs displayed a synergetic affect against methicillin-resistant S. aureus with MIC and MBC values of 15.6 and 62.5 µg/mL, respectively.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Farmacorresistência Bacteriana , Ouro/farmacologia , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Romã (Fruta)/química , Carboidratos/química , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Íons , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Tamanho da Partícula , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Carbohydr Polym ; 256: 117571, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483068

RESUMO

Aloe polysaccharides (APs) are well-known plant polysaccharides, but little is known about their digestion and fermentation characteristics in vitro. In this study, the molecular weight of APs had no significant changes after gastric and intestinal digestion. During the fecal fermentation, the content of volatiles and pH value decreased continuously, while the short-chain fatty acids (SCFAs) concentration increased significantly. Additionally, the abundance of the microbiota associated with the metabolism of SCFAs was increased, including Prevotella, Catenibacterium, Lachnospiraceae, and Coprococcus, while the harmful microbiota was decreased, like Escherichia-Shigella, and Veillonella. Moreover, bioinformatics analysis indicated that APs boosted fructose and mannose metabolism, and the gene expressions of enzymes, containing mannose-6-phosphate isomerase [EC:5.3.1.8]. Structural equation modeling also highlighted that SCFAs-producing microbiota were primary degraders of APs, suggesting APs may facilitate the manufacture of functional foods with the purpose of maintaining intestinal health.


Assuntos
Aloe/química , Fezes/microbiologia , Microbioma Gastrointestinal , Intestinos/patologia , Polissacarídeos/química , Estômago/patologia , Bactérias/classificação , Bactérias/metabolismo , Carboidratos/química , Carbonatos , Clostridiales , Biologia Computacional , Escherichia , Fermentação , Firmicutes , Alimento Funcional , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Intestinos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peso Molecular , Monossacarídeos , Prevotella , Shigella , Veillonella , Adulto Jovem
16.
Carbohydr Polym ; 251: 116725, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142548

RESUMO

The binding affinity and thermodynamics of family 4 carbohydrate-binding module (CBM4), belonging to type B CBM, on model surfaces of cellulose nanocrystals (CNC) and nanofibrils (CNF) were investigated by quartz crystal microbalance with dissipation monitoring (QCM-D) technology in real-time at different temperatures. The thermodynamic parameters associated with the interaction, such as Gibbs free energy, enthalpy change, entropy change and heat capacity were obtained using the van't Hoff analysis via a nonlinear parameter estimation. The results demonstrated CBM4 binds preferentially to both CNF and CNC, whereas the driving forces behind them were very different. The former was related to the hydrogen bonds formed in the CBM4 clefts, resulting in a favorable enthalpy but compensated by unfavorable entropy change; on the contrary, the latter was mainly driven by favorable entropy but compensated by unfavorable enthalpic change due to water rearrangement.


Assuntos
Celulose/química , Nanofibras/química , Nanopartículas/química , Adsorção , Sítios de Ligação , Carboidratos/química , Ligação de Hidrogênio , Microscopia de Força Atômica , Modelos Moleculares , Técnicas de Microbalança de Cristal de Quartzo , Termodinâmica
17.
J Sci Food Agric ; 101(2): 673-683, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32696494

RESUMO

BACKGROUND: Figs are highly perishable after harvest, and their storability and marketability are relatively short. This study aimed to determine the effects of fruit maturity on the physiological quality and targeted metabolites of 'Masui Dauphine' figs in two maturation stages (75% versus 100% commercial maturity) during cold storage. RESULTS: Fruit size and weight decreased during cold storage. Fruit respiration rate and color variables were lower at 100% maturity than at 75% maturity. Contents of soluble carbohydrates and organic acids differed according to fruit maturity. The levels of most free amino acids were decreased during cold storage; however, the levels of glutamine, serine and alanine were elevated in 100% mature fruits at the end of cold storage. The results of multivariate analyses indicated that the physiological properties of fruit and responses of targeted metabolites differed depending on fruit maturity during cold storage. CONCLUSIONS: The results suggested that fruit maturity plays a key role in controlling fruit quality of figs during cold storage. In practice, fruit maturity should be highly considered for the fresh fig market. © 2020 Society of Chemical Industry.


Assuntos
Ficus/crescimento & desenvolvimento , Frutas/química , Ácidos/química , Ácidos/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Metabolismo dos Carboidratos , Carboidratos/química , Temperatura Baixa , Ficus/química , Ficus/metabolismo , Armazenamento de Alimentos , Frutas/crescimento & desenvolvimento , Frutas/metabolismo
18.
J Sci Food Agric ; 101(1): 120-130, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32613628

RESUMO

BACKGROUND: An ultrasonic spray nozzle was evaluated for the production of powders and microcapsules, using blueberry extract, modified starch (HI-CAP 100), and whey protein isolate (WPI). The effects of ultrasonic power and the concentration of coating materials on the characteristics of the resulting samples - such as viscosity, particle size, microencapsulation efficiency, color, glass transition temperature, Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and morphology - were also studied. RESULTS: The apparent viscosity was primarily affected by the self-heating of the ultrasonic nozzle as the power increased. The largest mean particle size of samples was observed under conditions of 30% coating concentration at 10 W. Glass transition temperatures (Tg ) of the samples were affected by all atomization parameters significantly (P < 0.05) and the highest Tg values of all samples were determined when the coating concentration was maximum (30%) and power level was minimum (5 W). The FTIR and XRD results indicate that the power of the ultrasonic nozzle did not cause any change in WPI structure and led to only a small change in the structure of HI-CAP 100 at 10 W. The short atomization time preserved, to some extent, the properties of the coating materials and the blueberry extract. With regard to the morphological properties, it was observed that the samples obtained with WPI showed less shrinkage than HI-CAP 100. CONCLUSION: The results indicated that an ultrasonic nozzle could be used successfully to prepare the blueberry microcapsule with HI-CAP 100 and WPI as coating materials. This study may contribute to the development of ultrasonic nozzle applications using different coatings for the microencapsulation of high-quality functional materials. © 2020 Society of Chemical Industry.


Assuntos
Mirtilos Azuis (Planta)/química , Carboidratos/química , Tecnologia de Alimentos/métodos , Extratos Vegetais/química , Ultrassom/métodos , Proteínas do Soro do Leite/química , Cápsulas/química , Frutas/química , Tamanho da Partícula , Pós/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Temperatura , Ultrassom/instrumentação , Viscosidade , Difração de Raios X
19.
J Sci Food Agric ; 101(1): 334-340, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32627840

RESUMO

BACKGROUND: Perennial legumes cultivated under irrigation in the Mountain West USA have non-fibrous carbohydrate (NFC) concentrations exceeding 400 g kg-1 , a level commonly found in concentrate-based ruminant diets. Our objective was to determine the influence of NFC concentration and plant secondary compounds on in vitro rumen digestion of grass, legume and forb forages compared with digestion of their isolated neutral detergent fiber (NDF) fraction. Forages were composited from ungrazed paddocks of rotationally stocked, irrigated monoculture pastures between May and August 2016, frozen in the field, freeze-dried, and ground. RESULTS: The maximum rate (RMax ) of gas production was greater for the legumes alfalfa (ALF; Medicago sativa L.) and birdsfoot trefoil (BFT; Lotus corniculatus L.) than for the legume cicer milkvetch (CMV; Astragalus cicer L.) the grass meadow brome (MBG; Bromus riparius Rehm.) and the non-legume forb small burnet (SMB; Sanguisorba minor Scop.), and intermediate for the legume sainfoin (SNF; Onobrychis viciifolia Scop.). The RMax of isolated NDF was greatest for BFT and CMV, intermediate for ALF, SNF and SMB and least for MBG. CONCLUSIONS: More than 900 g of organic matter kg-1 dry matter of legumes was digested after 96 h. Across forages, the extent of whole-plant digestion increased with NFC and crude protein concentrations, decreased with NDF concentrations, and was modulated by secondary compounds. The extent of digestion of isolated NDF decreased with concentration of lignin and residual tannins. © 2020 Society of Chemical Industry.


Assuntos
Carboidratos/química , Bovinos/metabolismo , Medicago sativa/metabolismo , Rúmen/metabolismo , Ração Animal/análise , Animais , Metabolismo dos Carboidratos , Digestão , Lotus/química , Lotus/metabolismo , Medicago sativa/química , Poaceae/química , Poaceae/metabolismo
20.
Methods Mol Biol ; 2183: 305-312, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32959250

RESUMO

Conjugation, that is, covalent linkage, to immunological proteins is a common strategy to address the low immunogenicity issue of carbohydrate antigens in vaccine development. This chapter describes an easy and efficient method for oligosaccharide-protein conjugation employing dicarboxylic acid linkers. In this regard, a free amino group is introduced to an oligosaccharide antigen to facilitate coupling with the bifunctional linker upon reaction with its corresponding disuccinimidyl ester. The resultant monosuccinimidyl ester of the oligosaccharide antigen then reacts with the free amino groups of a carrier protein to provide the desired oligosaccharide-protein conjugate.


Assuntos
Proteínas de Transporte/química , Glicoconjugados/química , Glicoconjugados/imunologia , Oligossacarídeos/química , Oligossacarídeos/imunologia , Vacinas Conjugadas/química , Vacinas Conjugadas/imunologia , Adamantano/análogos & derivados , Adamantano/química , Carboidratos/química , Óxidos N-Cíclicos/química , Ácidos Dicarboxílicos/química , Eletroforese , Ésteres , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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