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1.
ACS Nano ; 18(42): 28764-28781, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39383310

RESUMO

Cancer cells have a high demand for sugars and express diverse carbohydrate receptors, offering opportunities to improve delivery with multivalent glycopolymer materials. However, effectively delivering glycopolymers to tumors while inhibiting cancer cell activity, altering cellular metabolism, and reversing tumor-associated macrophage (TAM) polarization to overcome immunosuppression remains a challenging area of research due to the lack of reagents capable of simultaneously achieving these objectives. Here, the glycopolymer-like condensed nanoparticle (∼60 nm) was developed by a one-pot carbonization reaction with a single precursor, promoting multivalent interactions for the galactose-related receptors of the M2 macrophage (TAM) and thereby regulating the STAT3/NF-κB pathways. The subsequently induced M2-to-M1 transition was increased with the condensed level of glycopolymer-like nanoparticles. We found that the activation of the glycopolymer-like condensed galactose (CG) nanoparticles influenced monocarboxylate transporter 4 (MCT-4) function, which caused inhibited lactate efflux (similar to inhibitor effects) from cancer cells. Upon internalization via galactose-related endocytosis, CG NPs induced cellular reactive oxygen species (ROS), leading to dual functionalities of cancer cell death and M2-to-M1 macrophage polarization, thereby reducing the tumor's acidic microenvironment and immunosuppression. Blocking the nanoparticle-MCT-4 interaction with antibodies reduced their toxicity in glioblastoma (GBM) and affected macrophage polarization. In orthotopic GBM and pancreatic cancer models, the nanoparticles remodeled the tumor microenvironment from "cold" to "hot", enhancing the efficacy of anti-PD-L1/anti-PD-1 therapy by promoting macrophage polarization and activating cytotoxic T lymphocytes (CTLs) and dendritic cells (DCs). These findings suggest that glycopolymer-like nanoparticles hold promise as a galactose-elicited adjuvant for precise immunotherapy, particularly in targeting hard-to-treat cancers.


Assuntos
Glioblastoma , Nanopartículas , Neoplasias Pancreáticas , Nanopartículas/química , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Humanos , Animais , Camundongos , Inibidores de Checkpoint Imunológico/química , Inibidores de Checkpoint Imunológico/farmacologia , Galactose/química , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Açúcares/química , Microambiente Tumoral/efeitos dos fármacos
2.
Molecules ; 29(20)2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39459189

RESUMO

The Maillard reaction (MR) involves interactions between reducing sugars and amino acids or proteins during heating, producing Maillard reaction products (MRPs) that influence food flavour, aroma, and colour. Some MRPs exhibit antioxidant properties, prompting interest in their potential as natural food preservatives. This study aimed to develop a method for detecting and identifying antioxidant MRPs using high-pressure liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (HRMS). By improving chromatographic conditions, the separation of antioxidant MRPs was optimised using known antioxidant MRPs as reference signals. This work also examined the effects of pH, reaction time, and different sugar-amino acid combinations on the production and composition of antioxidant MRPs. Results indicated that neutral to basic pH facilitated faster reactions, with pH 7 selected as optimal. A library of 50 m/z signals for potential antioxidant MRPs was created, and the best combinations of amino acids and sugars for their production were identified. These findings pave the way for more precise analyses of antioxidant MRPs, with future research focusing on isolating and characterising specific MRPs to understand their structures and mechanisms, ultimately contributing to the development of functional foods with natural antioxidant properties.


Assuntos
Aminoácidos , Antioxidantes , Conservantes de Alimentos , Reação de Maillard , Espectrometria de Massas , Antioxidantes/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Conservantes de Alimentos/química , Conservantes de Alimentos/análise , Aminoácidos/química , Aminoácidos/análise , Concentração de Íons de Hidrogênio , Açúcares/análise , Açúcares/química
3.
Carbohydr Res ; 544: 109244, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39180880

RESUMO

Sugars are vital biomolecules widely found in nature, playing an indispensable role in a plethora of biological processes. Similarly, coumarins are heterocycles with an effective pharmacophore skeleton, making them crucial in drug design and development. Coupling carbohydrate moieties to the small biologically active molecules creates a vast library of glycoconjugates with impressive structural diversity. The potential of coumarin glycosides is being extensively explored due to their broad spectrum of applications, including antibacterial, anticancer, and anticoagulant properties, etc. This review highlights various chemical methodologies for synthesizing diverse coumarin glycohybrids with distinct linkages and explores their immense biological potential, making a significant contribution to the field of organic synthesis.


Assuntos
Cumarínicos , Cumarínicos/química , Cumarínicos/síntese química , Humanos , Açúcares/química , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Estrutura Molecular
4.
Int J Biol Macromol ; 278(Pt 4): 134983, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39209591

RESUMO

Enzymatic treatment on lignocellulosic biomass has become a trend in preparing nanocellulose (NC), but the process must be optimized to guarantee high production yield and crystallinity. This study offers insights into an innovative protocol using cultivated fungal cellulase and xylanase to improve NC production from raw oil palm leaves (OPL) using five-factor-four-level Taguchi orthogonal design for optimizing parameters, namely substrate and enzyme loading, surfactant concentration, incubation temperature and time. Statistical results revealed the best condition for producing NC (66.06 % crystallinity, 43.59 % yield) required 10 % (w/v) substrate, 1 % (v/v) enzyme, 1.4 % (w/v) Tween-80, with 72-h incubation at 30 °C. Likewise, the highest sugar yield (47.07 %) was obtained using 2.5 % (w/v) substrate, 2.0 % (v/v) enzyme, 2.0 % (w/v) Tween-80, with 72-h incubation at 60 °C. The auxiliary enzymes used in this study, i.e., xylanase, produced higher crystallinity NC, showing widths between 8 and 12 nm and lengths >1 µm and sugars at 47.07 % yield. Thus, our findings proved that optimizing the single-step enzymatic hydrolysis of raw OPL could satisfactorily produce relatively crystalline NC and sugar yield for further transformation into bio-nanocomposites and biofuels. This study presented a simple, innovative protocol for NC synthesis showing characteristics comparable to the traditionally-prepared NC, which is vital for material's commercialization.


Assuntos
Celulase , Celulose , Folhas de Planta , Celulose/química , Celulose/biossíntese , Folhas de Planta/química , Celulase/química , Celulase/metabolismo , Açúcares/química , Arecaceae/química , Óleo de Palmeira/química , Biomassa , Temperatura , Hidrólise , Endo-1,4-beta-Xilanases/metabolismo , Endo-1,4-beta-Xilanases/química
5.
Acc Chem Res ; 57(16): 2234-2244, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39115809

RESUMO

ConspectusThe origin of the single chirality of the chemical building blocks of life remains an intriguing topic of research, even after decades of experimental and theoretical work proposing processes that may break symmetry and induce chiral amplification, a term that may be defined as the enhancement of enantiomeric excess starting from prochiral substrates or from a racemic mixture or a small imbalance between enantiomers. Studies aimed at understanding prebiotically plausible pathways to these molecules have often neglected the issue of chirality, with a focus on the stereochemical direction of these reactions generally being pursued after reaction discovery. Our work has explored how the stereochemical outcome for the synthesis of amino acids and sugars might be guided to rationalize the origin of biological homochirality. The mechanistic interconnection between enantioenrichment in these two groups of molecules provides insights concerning the handedness extant in modern biology. In five separate examples involving the synthesis of life's building blocks, including sugars, RNA precursors, amino acids, and peptides, kinetic resolution emerges as a key protocol for enantioenrichment from racemic molecules directed by chiral source molecules. Several of these examples involve means not only for chiral amplification but also symmetry breaking and chirality transfer across a range of racemic monomer molecules. Several important implications emerge from these studies: one, kinetic resolution of the primordial chiral sugar, glyceraldehyde, plays a key role in a number of different prebiotically plausible reactions; two, the emergence of homochirality in sugars and amino acids is inherently intertwined, with clear synergy between the biological hand of each molecule class; three, the origin story for the homochirality of enzymes and modern metabolism points toward kinetic resolution of racemic amino acids in networks that later evolved to include sophisticated and complete catalytic and co-catalytic cycles; four, a preference for heterochiral ligation forming product molecules that cannot lead to biologically competent polymers can in fact be a driving force for a route to homochiral polymer chains; and five, enantioenrichment in complex mixtures need not be addressed one compound at a time, because kinetic resolution induces symmetry breaking and chirality transfer that may lead to general protocols rather than specific cases tailored to each individual molecule. Such chirality transfer mechanisms perhaps presage strategies utilized in modern biology.Our latest work extends the study of monomer enantioenrichment to the ligation of these molecules into the extended homochiral chains leading to the complex polymers of modern biology. A central theme in all of these reactions is the key role that kinetic resolution of a racemic mixture of amino acids or sugars plays in enabling enantioenrichment under prebiotically plausible conditions. This work has uncovered important trends in symmetry breaking, chirality transfer, and chiral amplification. Kinetic resolution of racemic mixtures emerges as a general solution for chiral amplification in prebiotic chemistry, leading to the single chirality of complex biological molecules and genetic polymers.


Assuntos
Aminoácidos , Estereoisomerismo , Cinética , Aminoácidos/química , Peptídeos/química , Peptídeos/síntese química , Prebióticos , Origem da Vida , Açúcares/química , RNA/química
6.
Mol Pharm ; 21(6): 3017-3026, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38758116

RESUMO

Sucrose and trehalose pharmaceutical excipients are employed to stabilize protein therapeutics in a dried state. The mechanism of therapeutic protein stabilization is dependent on the sugars being present in an amorphous solid-state. Colyophilization of sugars with high glass transition polymers, polyvinylpyrrolidone (PVP), and poly(vinylpyrrolidone vinyl acetate) (PVPVA), enhances amorphous sugar stability. This study investigates the stability of colyophilized sugar-polymer systems in the frozen solution state, dried state postlyophilization, and upon exposure to elevated humidity. Binary systems of sucrose or trehalose with PVP or PVPVA were lyophilized with sugar/polymer ratios ranging from 2:8 to 8:2. Frozen sugar-PVPVA solutions exhibited a higher glass transition temperature of the maximally freeze-concentrated amorphous phase (Tg') compared to sugar-PVP solutions, despite the glass transition temperature (Tg) of PVPVA being lower than PVP. Tg values of all colyophilized systems were in a similar temperature range irrespective of polymer type. Greater hydrogen bonding between sugars and PVP and the lower hygroscopicity of PVPVA influenced polymer antiplasticization effects and the plasticization effects of residual water. Plasticization due to water sorption was investigated in a dynamic vapor sorption humidity ramping experiment. Lyophilized sucrose systems exhibited increased amorphous stability compared to trehalose upon exposure to the humidity. Recrystallization of trehalose was observed and stabilized by polymer addition. Lower concentrations of PVP inhibited trehalose recrystallization compared to PVPVA. These stabilizing effects were attributed to the increased hydrogen bonding between trehalose and PVP compared to trehalose and PVPVA. Overall, the study demonstrated how differences in polymer hygroscopicity and hydrogen bonding with sugars influence the stability of colyophilized amorphous dispersions. These insights into excipient solid-state stability are relevant to the development of stabilized biopharmaceutical solid-state formulations.


Assuntos
Estabilidade de Medicamentos , Excipientes , Liofilização , Polímeros , Povidona , Temperatura de Transição , Trealose , Liofilização/métodos , Povidona/química , Trealose/química , Excipientes/química , Polímeros/química , Sacarose/química , Açúcares/química , Ligação de Hidrogênio , Armazenamento de Medicamentos , Química Farmacêutica/métodos , Varredura Diferencial de Calorimetria , Umidade , Pirrolidinas/química , Compostos de Vinila/química
7.
Bioconjug Chem ; 35(6): 804-815, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38718344

RESUMO

Adjuvants are essential substances for vaccines and immunotherapies that enhance antigen-specific immune responses. Single-stranded oligodeoxynucleotides containing an unmethylated CpG motif (CpG ODNs) are agonistic ligands for toll-like receptor 9 that initiate an innate immune response. They represent promising adjuvants for antiviral and antitumor immunotherapies; however, CpG ODNs have some limitations, such as poor nuclease resistance and low cell membrane permeability. Therefore, an effective formulation is needed to improve the nuclease resistance and immunostimulatory effects of CpG ODNs. Previously, we demonstrated the selective delivery of a small molecule toll-like receptor 7 ligand to immune cells through sugar-binding receptors using sugar-immobilized gold nanoparticles (SGNPs), which significantly enhanced the potency of the ligand. In this study, we examined SGNPs as carriers for partially phosphorothioated A-type CpG ODN (D35) and an entirely phosphorothioated B-type CpG ODN (K3) and evaluated the functionality of the sugar moiety on SGNPs immobilized with CpG ODN. SGNPs immobilized with D35 (D35-SGNPs) exhibited improved nuclease resistance and the in vitro and in vivo potency was significantly higher compared with that of unconjugated D35. Furthermore, the sugar structure on the GNPs was a significant factor in enhancing the cell internalization ability, and enhanced intracellular delivery of D35 resulted in improving the potencies of the A-type CpG ODN, D35. SGNPs immobilized with K3 (K3-SGNPs) exhibited significantly higher induction activities for both humoral and cellular immunity compared with unconjugated K3 and D35-SGNPs. On the other hand, sugar structure on K3-SGNPs did not affect the immunostimulatory effects. These results indicate that the sugar moiety on K3-SGNPs primarily functions as a hydrophilic dispersant for GNPs and the formulation of K3 to SGNPs contributes to improving the immunostimulatory activity of K3. Because our CpG ODN-SGNPs have superior induction activities for antigen-specific T-cell mediated immune responses, they may be effective adjuvants for vaccines and immunotherapies.


Assuntos
Adjuvantes Imunológicos , Ouro , Nanopartículas Metálicas , Oligodesoxirribonucleotídeos , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Animais , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Camundongos , Açúcares/química , Humanos , Camundongos Endogâmicos C57BL
8.
Food Chem ; 450: 139322, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38613963

RESUMO

This paper develops a new hybrid, automated, and non-invasive approach by combining hyper-spectral imaging, Savitzky-Golay (SG) Filter, Principal Components Analysis (PCA), Machine Learning (ML) classifiers/regressors, and stacking generalization methods to detect sugar in honey. First, the 32 different sugar concentration levels in honey were predicted using various ML regressors. Second, the six ranges of sugar were classified using various classifiers. Third, the 11 types of honey and 100% sugar were classified using classifiers. The stacking model (STM) obtained R2: 0.999, RMSE: 0.493 ml (v/v), RPD: 40.2, a 10-fold average R2: 0.996 and RMSE: 1.27 ml (v/v) for predicting 32 sugar concentrations. The STM achieved a Matthews Correlation Coefficient (MCC) of 99.7% and a Kappa score of 99.7%, a 10-fold average MCC of 98.9% and a Kappa score of 98.9% for classifying the six sugar ranges and 12 categories of honey types and a sugar.


Assuntos
Contaminação de Alimentos , Mel , Açúcares , Mel/análise , Contaminação de Alimentos/análise , Açúcares/análise , Açúcares/química , Aprendizado de Máquina , Análise de Componente Principal , Análise Espectral/métodos , Carboidratos/química , Carboidratos/análise
9.
ACS Appl Mater Interfaces ; 14(2): 2618-2628, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34989547

RESUMO

Intracellular delivery of functional molecules is of great importance in various biomedical and biotechnology applications. Recently, nanoparticle-based photothermal poration has attracted increasing attention because it provided a facile and efficient method to permeabilize cells transiently, facilitating the entry of exogenous molecules into cells. However, this method still has some safety concerns associated with the nanoparticles that bind to the cell membranes or enter the cells. Herein, a nanoplatform with both photothermal property and sugar-triggered cleaning ability for intracellular delivery is developed based on phenylboronic acid (PBA) functionalized porous magnetic nanoparticles (named as M-PBA). The M-PBA particles could bind to the target cells effectively through the specific interactions between PBA groups and the cis-diol containing components on the cell membrane. During a short-term near-infrared irradiation, the bound particles convert absorbed light energy to heat, enabling high-efficiency delivery of various exogenous molecules into the target cells via a photothermal poration mechanism. After delivery, the bound particles could be easily "cleaned" from the cell surface via mild sugar-treatment and collected by a magnet, avoiding the possible side effects caused by the entrance of particles or their fragments. The delivery and cleaning process is short and effective without compromising the viability and proliferation ability of the cells with delivered molecules, suggesting that the M-PBA particles could be used as promising intracellular delivery agents with a unique combination of efficiency, safety, and flexibility.


Assuntos
Materiais Biocompatíveis/química , Ácidos Borônicos/química , Sistemas de Liberação de Medicamentos , Nanopartículas de Magnetita/química , Fototerapia , Açúcares/química , Membrana Celular/química , Células HeLa , Humanos , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula , Células Tumorais Cultivadas
10.
Toxicol In Vitro ; 78: 105270, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34757181

RESUMO

The biopersistence of fiber materials is one of the cornerstones in estimating potential risk to human health upon inhalation. To connect epidemiological and in vivo investigations with in vitro studies, reliable and robust methods of fiber biopersistence determination and understanding of fiber dissolution mechanism are required. We investigated dissolution properties of oil treated stone wool fibers with and without sugar-based binder (SBB) at 37 °C in the liquids representing macrophages intracellular conditions (pH 4.5). Conditions varied from batch to flow of different rates. Fiber morphology and surface chemistry changes caused by dissolution were monitored with scanning electron microscopy and time-of-flight secondary ion mass spectrometry mapping. Stone wool fiber dissolution rate depends on liquid composition (presence of ligands, such as citrate), pH, reaction products transport and fibers wetting properties. The dissolution rate decreases when: 1) citrate is consumed by the reaction with the released Al cations; 2) the pH increases during a reaction in poorly buffered solutions; 3) the dissolution products are accumulated; 4) fibers are not fully wetted with the fluid. Presence of SBB has no influence on dissolution rate if fiber material was wetted prior to dissolution experiment to avoid poorly wetted fiber agglomerates formation in the synthetic lung fluids.


Assuntos
Fibras Minerais/análise , Solubilidade , Pulmão , Microscopia Eletrônica de Varredura , Espectrometria de Massa de Íon Secundário , Açúcares/química
11.
Bioorg Med Chem ; 52: 116501, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34837817

RESUMO

In this work, we have developed an approach for the synthesis of sugar amino acid oligomers based on the glucosamine scaffold. We found that the solid-phase approach was unsuccessful for the preparation of sugar amino acid oligomers and the limitation of the liquid-phase approach revolved around the low solubility of larger oligomers. Nevertheless, this strategy allowed the coupling of alkynylated carbohydrate amino acids with podophyllotoxin-bearing an azide functional group yielding novel podophyllotoxin analogues. Due to their low solubility, the antiproliferative study revealed no anticancer activity of these newly synthesized analogues.


Assuntos
Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Desenvolvimento de Medicamentos , Podofilotoxina/farmacologia , Açúcares/farmacologia , Aminoácidos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Podofilotoxina/química , Relação Estrutura-Atividade , Açúcares/química
12.
Sci Rep ; 11(1): 20877, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686689

RESUMO

Adenovirus vectors offer a platform technology for vaccine development. The value of the platform has been proven during the COVID-19 pandemic. Although good stability at 2-8 °C is an advantage of the platform, non-cold-chain distribution would have substantial advantages, in particular in low-income countries. We have previously reported a novel, potentially less expensive thermostabilisation approach using a combination of simple sugars and glass micro-fibrous matrix, achieving excellent recovery of adenovirus-vectored vaccines after storage at temperatures as high as 45 °C. This matrix is, however, prone to fragmentation and so not suitable for clinical translation. Here, we report an investigation of alternative fibrous matrices which might be suitable for clinical use. A number of commercially-available matrices permitted good protein recovery, quality of sugar glass and moisture content of the dried product but did not achieve the thermostabilisation performance of the original glass fibre matrix. We therefore further investigated physical and chemical characteristics of the glass fibre matrix and its components, finding that the polyvinyl alcohol present in the glass fibre matrix assists vaccine stability. This finding enabled us to identify a potentially biocompatible matrix with encouraging performance. We discuss remaining challenges for transfer of the technology into clinical use, including reliability of process performance.


Assuntos
Adenoviridae/genética , Vacinas contra Adenovirus/química , Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Potência de Vacina , Adenovirus dos Símios , Materiais Biocompatíveis , Varredura Diferencial de Calorimetria , Vidro , Células HEK293 , Humanos , Luz , Espectroscopia de Ressonância Magnética , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Álcool de Polivinil , Vacina Antirrábica , Espalhamento de Radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Açúcares/química , Temperatura , Termogravimetria , Trealose/química
13.
Int J Mol Sci ; 22(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34281292

RESUMO

Cancer is one of the deadliest illness globally. Searching for new solutions in cancer treatments is essential because commonly used mixed, targeted and personalized therapies are sometimes not sufficient or are too expensive for common patients. Sugar fatty acid esters (SFAEs) are already well-known as promising candidates for an alternative medical tool. The manuscript brings the reader closer to methods of obtaining various SFAEs using combined biological, chemical and enzymatic methods. It presents how modification of SFAE's hydrophobic chains can influence their cytotoxicity against human skin melanoma and prostate cancer cell lines. The compound's cytotoxicity was determined by an MTT assay, which followed an assessment of SFAEs' potential metastatic properties in concentrations below IC50 values. Despite relatively high IC50 values (63.3-1737.6 µM) of the newly synthesized SFAE, they can compete with other sugar esters already described in the literature. The chosen bioactives caused low polymerization of microtubules and the depolymerization of actin filaments in nontoxic levels, which suggest an apoptotic rather than metastatic process. Altogether, cancer cells showed no propensity for metastasis after treating them with SFAE. They confirmed that lactose-based compounds seem the most promising surfactants among tested sugar esters. This manuscript creates a benchmark for creation of novel anticancer agents based on 3-hydroxylated fatty acids of bacterial origin.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/farmacologia , Açúcares/química , Açúcares/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Ésteres/química , Ésteres/farmacologia , Feminino , Humanos , Filamentos Intermediários/efeitos dos fármacos , Filamentos Intermediários/ultraestrutura , Masculino , Relação Estrutura-Atividade
14.
Carbohydr Polym ; 268: 118259, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34127229

RESUMO

Nitrocellulose (NC) membrane can have value-added applications for lateral flow assay (LFA)-based diagnostic tools, which has great potential for the detection of pathogens, such as COVID-19, in different environments. However, poor sensitivity of the NC membrane based LFA limits its further application in many cases. Herein, we developed a facile method for LFA sensitivity enhancement, by incorporating two-sugar barrier into LFAs: one between the conjugation pad and the test line, and the other between the test line and the control line. ORF1ab nucleic acid of COVID-19 was used as the model target to demonstrate the concept on the HF120 membrane. Results show that at optimum conditions, the two sugar barrier LFAs have a detection limit of 0.5 nM, which is compared to that of 2.5 nM for the control LFA, achieving a 5-fold sensitivity increase. This low cost, easy-to-fabricate and easy-to-integrate LFA method may have potential applications in other cellulose paper-based platforms.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , Colódio/química , RNA Mensageiro/análise , Açúcares/química , Proteínas Virais/genética , Teste de Ácido Nucleico para COVID-19/instrumentação , DNA/química , Sondas de DNA/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Poliproteínas/genética , SARS-CoV-2/química , Sensibilidade e Especificidade
15.
Molecules ; 26(9)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946573

RESUMO

The present study aimed to evaluate the effect of Jerusalem artichoke processing methods and drying methods (freeze drying, sublimation drying, vacuum drying) on the basic physicochemical parameters, profiles and contents of sugars and polyphenolic compounds, and health-promoting properties (antioxidant activity, inhibition of the activities of α-amylase, α-glucosidase, and pancreatic lipase) of the produced purée. A total of 25 polyphenolic compounds belonging to hydroxycinnamic phenolic acids (LC-PDA-MS-QTof) were detected in Jerusalem artichoke purée. Their average content in the raw material was at 820 mg/100 g dm (UPLC-PDA-FL) and was 2.7 times higher than in the cooked material. The chemical composition and the health-promoting value of the purées were affected by the drying method, with the most beneficial values of the evaluated parameters obtained upon freeze drying. Vacuum drying could offer an alternative to freeze drying, as both methods ensured relatively comparable values of the assessed parameters.


Assuntos
Fenômenos Químicos , Alimento Funcional/análise , Helianthus/química , Extratos Vegetais/química , Antioxidantes/química , Antioxidantes/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/química , Açúcares/química
16.
Food Chem ; 355: 129566, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33799250

RESUMO

The chemical composition and functionality of molecular fractions associated with dry white wines oxidative stability remain poorly understood. In the present study, DPPH assay, electron paramagnetic resonance spectroscopy (EPR) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) were used to explore the chemical diversity associated with the antioxidant capacity (AC) of white wines. AC determined using the DPPH assay and EPR were complementary and enabled differentiation of wine samples into groups with low, medium, and high AC. Mass spectra variations associated with global DPPH- and EPR-derived indices enabled identification of 365 molecular markers correlated with samples with high AC, of which 32% were CHO compounds including phenolic and sugar derivatives, 20% were CHOS and 36% were CHONS compounds including cysteine-containing peptides. This study confirmed the importance of CHONS and CHOS compounds in the antioxidant metabolome of dry white wines. Knowledge about these compounds will enable better understanding of the oxidative stability of white wines and therefore aid in achieving optimum shelf life.


Assuntos
Antioxidantes/química , Espectroscopia de Ressonância de Spin Eletrônica , Espectrometria de Massas/métodos , Vinho/análise , Análise por Conglomerados , Análise Discriminante , Fenóis/química , Análise de Componente Principal , Açúcares/química
17.
Amino Acids ; 53(2): 281-294, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33559000

RESUMO

Complementary to hydrophobic five membered ring ß-amino acids (e.g. ACPC), ß-sugar amino acids (ß-SAAs) have found increasing application as hydrophilic building blocks of foldamers and α/ß chimeric peptides. Fmoc-protected ß-SAAs [e.g. Fmoc-RibAFU(ip)-OH] are indeed useful Lego elements, ready to use for SPPS. The removal of 1,2-OH isopropylidene protecting group increasing the hydrophilicity of such SAA is presented here. We first used N3-RibAFU(ip)-OH model compound to optimize mild deprotection conditions. The formation of the 1,2-OH free product N3-RibAFU-OH and its methyl glycoside methyl ester, N3-RibAFU(Me)-OMe were monitored by RP-HPLC and found that either 50% TFA or 8 eqv. Amberlite IR-120 H+ resin in MeOH are optimal reagents for the effective deprotection. These conditions were then successfully applied for the synthesis of chimeric oligopeptide: -GG-X-GG- [X=RibAFU(ip)]. We found the established conditions to be effective and-at the same time-sufficiently mild to remove 1,2-O-isopropylidene protection and thus, it is proposed to be used in the synthesis of oligo- and polypeptides of complex sequence combination.


Assuntos
Alcenos/química , Aminoácidos/química , Oligopeptídeos/química , Açúcares/química , Sequência de Aminoácidos , Oligopeptídeos/síntese química
18.
Macromol Biosci ; 21(4): e2000341, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33502108

RESUMO

To provide high-quality cellular raw materials for cell engineering and pharmaceutical engineering, a polymer substrate is prepared for cell separation focusing on the cell proliferation cycle. There are many types of sugar chains on cell membranes, which function as signaling molecules to control interactions with the exterior of the cell; their abundance changes during the cell-proliferation cycle. In this study, a phenylboronic acid group, which has affinity for sugar chains, is introduced into a polymer containing a phosphorylcholine group that does not induce cell activation. On the surface of this polymer, human promyelocytic leukemia cells can adhere. The adhesion rate is increased by pretreating the substrate with an alkaline solution. Moreover, cell adhesion is dependent on the sugar additive in the culture medium. Therefore, cell adhesion is governed by reactions between the sugar chain on the cell membrane and the phenylboronic acid groups on the substrate. It is revealed that the adhesion rate changes depending on the expression level of sugar chains related to the cell-proliferation cycle. Based on this, it may be proposed a cell proliferation cycle-specific separation process using the polymer substrate based on cell adhesion depending on sugar chain density.


Assuntos
Fosfolipídeos/química , Fosforilcolina/química , Polímeros/química , Medicina Regenerativa/métodos , Ácidos Borônicos/química , Adesão Celular , Ciclo Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células , Meios de Cultura , Células HL-60 , Humanos , Metacrilatos/química , Espectroscopia Fotoeletrônica , Transdução de Sinais , Especificidade por Substrato , Açúcares/química , Propriedades de Superfície
19.
J Sci Food Agric ; 101(11): 4561-4569, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33460464

RESUMO

BACKGROUND: Acrylamide in foods has been widely studied because of its possible carcinogenicity. Most of the foods investigated were prepared using low moisture and high temperature conditions. Non-centrifugal sugars (NCSs), which have been promoted as 'non-chemical' natural sweeteners, contain precursors of acrylamide and their production processes involved prolonged heating. The acrylamide content in 32 commercial NCSs from coconut, cane and palmyra palm purchased in Asian countries was investigated. Additionally, syrups (80 o Brix) produced from coconut and palmyra raw saps and cane juice were prepared by evaporation with prolonged heating (2.5 h to reach 100 °C, 1 h to increase to 110 °C, held at 110 °C for 30 min). The compositions and contents of sugars, amino acids and minerals, as well as the physical characteristics of the raw saps, juice and syrups, were determined. RESULTS: The acrylamide content of these 32 products ranged from < 15 to 4011 µg kg-1 . The raw saps and juice were mildly acidic (pH 5.14-5.66) and similar values were observed for their syrups (4.73-5.73). The contents of sucrose, fructose and glucose in the saps and juice from these plants were similar, whereas their compositions varied with respect to amino acids. The variation of the ornithine content was significant, demonstrating a striking influence on the extent of acrylamide formation (867-1564 µg kg-1 ) in the syrups prepared from these materials. CONCLUSION: The present study emphasizes the importance of a careful monitoring and control of the critical steps invloved in the manufacturing process of NCSs (particularly the evaporation phase), aiming to protect the health and safety of consumers. © 2021 Society of Chemical Industry.


Assuntos
Acrilamida/química , Cocos/química , Contaminação de Alimentos/análise , Saccharum/química , Açúcares/química , Aminoácidos/química , Ásia , Culinária , Temperatura Alta , Reação de Maillard
20.
Biotechnol Lett ; 43(5): 967-979, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33517513

RESUMO

OBJECTIVE: The extraction of the hemicellulose fraction of sugarcane bagasse (SCB) by acid hydrolysis was evaluated in an autoclave and a Parr reactor aiming the application of the hydrolysate as a carbon source for lipid production by Lipomyces starkeyi. RESULTS: The hydrolysis that resulted in the highest sugar concentration was obtained by treatment in the Parr reactor (HHR) at 1.5% (m/v) H2SO4 and 120 °C for 20 min, reaching a hemicellulose conversion of approximately 82%. The adaptation of the yeast to the hydrolysate provided good fermentability and no lag phase. The fermentation of hemicellulose-derived sugars (HHR) by L. starkeyi resulted in a 27.8% (w/w) lipid content and YP/S of 0.16 g/l.h. Increasing the inoculum size increased the lipid content by approximately 61%, reaching 44.8% (w/w). CONCLUSION: The hemicellulose hydrolysate from SCB is a potential substrate for L. starkeyi to produce lipids for biodiesel synthesis based on the biorefinery concept.


Assuntos
Lipomyces/metabolismo , Óleos/metabolismo , Polissacarídeos/química , Saccharum/química , Adaptação Fisiológica , Biocombustíveis , Reatores Biológicos , Celulose/química , Celulose/metabolismo , Fermentação , Temperatura Alta , Hidrólise , Lipídeos/biossíntese , Lipomyces/crescimento & desenvolvimento , Polissacarídeos/metabolismo , Açúcares/química , Açúcares/metabolismo , Ácidos Sulfúricos/química
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