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1.
Sci Rep ; 13(1): 99, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596824

RESUMO

Fermentation of dietary fiber by gut microbes produces short-chain fatty acids (SCFA), but fermentation outcomes are affected by dietary fiber source and microbiota composition. The aim of this study was to investigate the effect of two different fecal microbial compositions on in vitro fermentation of a standardized amount of oat, rye, and wheat breads. Two human fecal donors with different microbial community composition were recruited. Bread samples were digested enzymatically. An in vitro fermentation model was used to study SCFA production, dietary fiber degradation, pH, and changes in microbiota. Feces from donor I had high relative abundance of Bacteroides and Escherichia/Shigella, whereas feces from donor II were high in Prevotella and Subdoligranulum. Shifts in microbiota composition were observed during fermentation. SCFA levels were low in the samples with fecal microbiota from donor I after 8 h of fermentation, but after 24 h acetate and propionate levels were similar in the samples from the different donors. Butyrate levels were higher in the fermentation samples from donor II, especially with rye substrate, where high abundance of Subdoligranulum was observed. Dietary fiber degradation was also higher in the fermentation samples from donor II. In conclusion, fermentation capacity and substrate utilization differed between the two different microbiota compositions.


Assuntos
Microbiota , Triticum , Humanos , Triticum/metabolismo , Pão , Secale/metabolismo , Avena/metabolismo , Fermentação , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fibras na Dieta/metabolismo
2.
Drug Deliv ; 30(1): 2162158, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36587626

RESUMO

Genistein (GEN), an isoflavonoid, offers multifunctional biological activities. However, its poor oral bioavailability, aqueous solubility, extensive metabolism, and short half-life restricted its clinical use. Therefore, the Phospholipon®90H complex of genistein (GPLC) was prepared to enhance its biopharmaceutical properties and anti-inflammatory activity. GPLC was characterized by employing particle size and zeta potential, Fourier transforms infrared spectrophotometry, differential scanning calorimetry, powder x-ray diffractometry, proton nuclear magnetic resonance, aqueous solubility, in vitro dissolution, ex vivo permeation, oral bioavailability and in vivo anti-inflammatory activity. The complex showed high entrapment of GEN (∼97.88% w/w) within the Phospholipon®90H matrix. Particle size and zeta potential studies confirmed the small particle size with the modest stability of GPLC. The characterization analysis supported the formation of GPLC through the participation of hydrogen bonding between GEN and Phospholipon®90H. GPLC significantly enhanced the aqueous solubility (∼2-fold) compared to GEN. Dissolution studies revealed that GPLC drastically improved the GEN dissolution rate compared to GEN. Likewise, the complex improved the permeation rate across the membrane compared to GEN. GPLC formulation significantly enhanced the oral bioavailability of GEN via improving its Cmax, tmax, AUC, half-life and mean residence time within the blood circulation compared to GEN. The GPLC (∼20 mg/kg, p.o.) remarkably inhibited the increase in paw edema up to 5 h, compared to GEN and diclofenac. Results suggest that the Phospholipon®90 complex is a superior and promising carrier for enhancing the biopharmaceutical parameters of GEN and other bioactive with similar properties.


Assuntos
Produtos Biológicos , Genisteína , Genisteína/farmacologia , Genisteína/química , Disponibilidade Biológica , Solubilidade , Anti-Inflamatórios/farmacologia , Administração Oral , Tamanho da Partícula , Varredura Diferencial de Calorimetria
3.
Nutrients ; 15(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36678322

RESUMO

Neurodegenerative diseases are known for their wide range of harmful conditions related to progressive cell damage, nervous system connections and neuronal death. These pathologies promote the loss of essential motor and cognitive functions, such as mobility, learning and sensation. Neurodegeneration affects millions of people worldwide, and no integral cure has been created yet. Here, bioactive compounds have been proven to exert numerous beneficial effects due to their remarkable bioactivity, so they could be considered as great options for the development of new neuroprotective strategies. Phenolic bioactives have been reported to be found in edible part of plants; however, over the last years, a large amount of research has focused on the phenolic richness that plant by-products possess, which sometimes even exceeds the content in the pulp. Thus, their possible application as an emergent neuroprotective technique could also be considered as an optimal strategy to revalorize these agricultural residues (those originated from plant processing). This review aims to summarize main triggers of neurodegeneration, revise the state of the art in plant extracts and their role in avoiding neurodegeneration and discuss how their main phenolic compounds could exert their neuroprotective effects. For this purpose, a diverse search of studies has been conducted, gathering a large number of papers where by-products were used as strong sources of phenolic compounds for their neuroprotective properties. Finally, although a lack of investigation is quite remarkable and greatly limits the use of these compounds, phenolics remain attractive for research into new multifactorial anti-neurodegenerative nutraceuticals.


Assuntos
Doenças Neurodegenerativas , Fármacos Neuroprotetores , Humanos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fenóis/farmacologia , Fenóis/química , Antioxidantes/farmacologia , Antioxidantes/química , Doenças Neurodegenerativas/prevenção & controle , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Plantas/química
4.
Nutrients ; 15(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36678328

RESUMO

Hypertension (HTN) is the leading cause of premature deaths worldwide and the main preventable risk factor for cardiovascular diseases. Therefore, there is a current need for new therapeutics to manage this condition. In this regard, protein hydrolysates containing antihypertensive bioactive peptides are of increasing interest. Thus, agri-food industry byproducts have emerged as a valuable source to obtain these hydrolysates as they are rich in proteins and inexpensive. Among these, byproducts from animal origin stand out as they are abundantly generated worldwide. Hence, this review is focused on evaluating the potential role of chicken slaughterhouse byproducts as a source of peptides for managing HTN. Several of these byproducts such as blood, bones, skins, and especially, chicken feet have been used to obtain protein hydrolysates with angiotensin-converting enzyme (ACE)-inhibitory activity and blood pressure-lowering effects. An increase in levels of endogenous antioxidant compounds, a reduction in ACE activity, and an improvement of HTN-associated endothelial dysfunction were the mechanisms underlying their effects. However, most of these studies were carried out in animal models, and further clinical studies are needed in order to confirm these antihypertensive properties. This would increase the value of these byproducts, contributing to the circular economy model of slaughterhouses.


Assuntos
Anti-Hipertensivos , Hipertensão , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/química , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Galinhas/metabolismo , Matadouros , Hidrolisados de Proteína/farmacologia , Peptídeos/farmacologia , Hipertensão/tratamento farmacológico
5.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679364

RESUMO

This paper proposes a new optical biosensor composed of a silicon-on-insulator (SOI) p-n junction photodiode (PD) with a surface plasmon (SP) antenna. When the phase-matching condition between two lateral wavelengths of the diffracted light from the SP antenna and the waveguiding mode in the SOI PD is satisfied, we observe sharp peaks in the spectroscopic light sensitivity. Since the peak wavelength depends on the RI change around the SP antenna corresponding to the phase-matching condition, the SOI PDs with an SP antenna can be applied to the optical biosensor. The RI detection limit is evaluated in the measurements with bulk solutions, and 1.11 × 10-5 RIU (refractive index unit) can be obtained, which is comparable to that of a surface plasmon resonance (SPR) sensor, which is well known as a representative optical biosensor. In addition, the response for intermolecular bonds is estimated by the electromagnetic simulations using the finite-difference time-domain (FDTD) method to clarify its ability to detect biomolecular interactions. The results of this paper will provide new ground for high-throughput label-free biosensing, since a large number of SOI PDs with an SP antenna can be easily integrated on a single chip via an SOI complementary metal-oxide-semiconductor (CMOS) fabrication process.


Assuntos
Técnicas Biossensoriais , Silício , Silício/química , Refratometria , Ressonância de Plasmônio de Superfície , Dióxido de Silício
6.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679372

RESUMO

Tea polyphenols, amino acids, soluble sugars, and other ingredients in fresh tea leaves are the key parameters of tea quality. In this research, a tea leaf ingredient estimation sensor was developed based on a multi-channel spectral sensor. The experiment showed that the device could effectively acquire 700-1000 nm spectral data of tea tree leaves and could display the ingredients of leaf samples in real time through the visual interactive interface. The spectral data of Fuding white tea tree leaves acquired by the detection device were used to build an ingredient content prediction model based on the ridge regression model and random forest algorithm. As a result, the prediction model based on the random forest algorithm with better prediction performance was loaded into the ingredient detection device. Verification experiment showed that the root mean square error (RMSE) and determination coefficient (R2) in the prediction were, respectively, as follows: moisture content (1.61 and 0.35), free amino acid content (0.16 and 0.79), tea polyphenol content (1.35 and 0.28), sugar content (0.14 and 0.33), nitrogen content (1.15 and 0.91), and chlorophyll content (0.02 and 0.97). As a result, the device can predict some parameters with high accuracy (nitrogen, chlorophyll, free amino acid) but some of them with lower accuracy (moisture, polyphenol, sugar) based on the R2 values. The tea leaf ingredient estimation sensor could realize rapid non-destructive detection of key ingredients affecting tea quality, which is conducive to real-time monitoring of the current quality of tea leaves, evaluating the status during tea tree growth, and improving the quality of tea production. The application of this research will be helpful for the automatic management of tea plantations.


Assuntos
Clorofila , Chá , Chá/química , Clorofila/análise , Aminoácidos/análise , Folhas de Planta/química , Polifenóis/análise , Polifenóis/metabolismo , Nitrogênio/análise , Açúcares/análise
7.
Sensors (Basel) ; 23(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36679398

RESUMO

This article presents a novel and selective electrochemical bioassay with antibody and laccase for the determination of free thyroid hormone (free triiodothyronine, fT3). The biosensor was based on a glassy carbon electrode modified with a Fe3O4@graphene nanocomposite with semiconducting properties, an antibody (anti-PDIA3) with high affinity for fT3, and laccase, which was responsible for catalyzing the redox reaction of fT3. The electrode modification procedure was investigated using a cyclic voltammetry technique, based on the response of the peak current after modifications. All characteristic working parameters of the developed biosensor were analyzed using differential pulse voltammetry. Obtained experimental results showed that the biosensor revealed a sensitive response to fT3 in a concentration range of 10-200 µM, a detection limit equal to 27 nM, and a limit of quantification equal to 45.9 nM. Additionally, the constructed biosensor was selective towards fT3, even in the presence of interference substances: ascorbic acid, tyrosine, and levothyroxine, and was applied for the analysis of fT3 in synthetic serum samples with excellent recovery results. The designed biosensor also exhibited good stability and can find application in future medical diagnostics.


Assuntos
Técnicas Biossensoriais , Grafite , Nanocompostos , Grafite/química , Lacase/química , Técnicas Eletroquímicas/métodos , Nanocompostos/química , Técnicas Biossensoriais/métodos , Hormônios Tireóideos , Eletrodos , Limite de Detecção
8.
Sensors (Basel) ; 23(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36679445

RESUMO

Glyphosate (GLYP) is a broad-spectrum, nonselective, organic phosphine postemergence herbicide registered for many food and nonfood fields. Herein, we developed a biosensor (Mbs@dsDNA) based on carboxylated modified magnetic beads incubated with NH2-polyA and then hybridized with polyT-glyphosate aptamer and complementary DNA. Afterwards, a quantitative detection method based on qPCR was established. When the glyphosate aptamer on Mbs@dsDNA specifically recognizes glyphosate, complementary DNA is released and then enters the qPCR signal amplification process. The linear range of the method was 0.6 µmol/L-30 mmol/L and the detection limit was set at 0.6 µmol/L. The recoveries in tap water ranged from 103.4 to 104.9% and the relative standard deviations (RSDs) were <1%. The aptamer proposed in this study has good potential for recognizing glyphosate. The detection method combined with qPCR might have good application prospects in detecting and supervising other pesticide residues.


Assuntos
Aptâmeros de Nucleotídeos , DNA , DNA Complementar , DNA/química , Corantes , Aptâmeros de Nucleotídeos/química , Água
9.
Sensors (Basel) ; 23(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36679459

RESUMO

Fresh tea leaves continuously lose water after harvesting, and the level of water content directly affects the configuration of tea processing parameters. To address this problem, this study established an online detection system for the water content of fresh tea leaves after harvesting based on near-infrared spectroscopy. The online acquisition and analysis system of the temperature and humidity sensor signal data was developed based on LabVIEW and Python software platforms. Near-infrared spectral data, environmental temperature, and humidity were collected from fresh leaves after harvesting. Spectral data were combined with PLS (partial least squares) to develop a prediction model for the water content of fresh tea leaves. Simultaneously, data communication between LabVIEW and PLC was established, laying the foundation for establishing a feedback mechanism to send the prediction results to the main platform of the lower computer. This provides a more objective and accurate basis for the detection of fresh leaves before processing and regulation during processing, thereby effectively promoting the standardisation and intelligent development of tea-processing equipment.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Água , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Água/análise , Chá/química , Padrões de Referência , Folhas de Planta/química , Análise dos Mínimos Quadrados
10.
Sensors (Basel) ; 23(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36679492

RESUMO

Designing highly active material to fabricate a high-performance noninvasive wearable glucose sensor was of great importance for diabetes monitoring. In this work, we developed CuxO nanoflakes (NFs)/Cu nanoparticles (NPs) nanocomposites to serve as the sensing materials for noninvasive sweat-based wearable glucose sensors. We involve CuCl2 to enhance the oxidation of Cu NPs to generate Cu2O/CuO NFs on the surface. Due to more active sites endowed by the CuxO NFs, the as-prepared sample exhibited high sensitivity (779 µA mM-1 cm-2) for noninvasive wearable sweat sensing. Combined with a low detection limit (79.1 nM), high selectivity and the durability of bending and twisting, the CuxO NFs/Cu NPs-based sensor can detect the glucose level change of sweat in daily life. Such a high-performance wearable sensor fabricated by a convenient method provides a facile way to design copper oxide nanomaterials for noninvasive wearable glucose sensors.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Nanopartículas , Dispositivos Eletrônicos Vestíveis , Nanocompostos/química , Cobre/química , Glucose/química
11.
Sensors (Basel) ; 23(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679600

RESUMO

The present study aimed to develop and characterize new heavy metal sensors functionalized by extracellular polymeric substances (EPSs) isolated from a Tunisian thermophilic microalga strain Graesiella sp. The elaborated sensor showed a highly homogeneous character and revealed a microstructural lamellar arrangement, high crystalline nature, and several functional groups. Electrochemical impedance spectroscopy (EIS) and acoustic wave sensing were used as sensing techniques to explore the ability of microalgae-EPS-functionalized sensors to detect cadmium and mercury as heavy metals. For impedimetric measurements, a two-dipole circuit was adopted and showed good-fitted results with a low total error. The acoustic sensor platforms showed good compatibility with EPS in adjacent water. For both EPS-functionalized sensors, metal ions (Cd2+, Hg2+) were successfully detected in the concentration range from 10-10 M to 10-4 M. Impedimetric sensor was more sensitive to Cd2+ at low concentrations before saturation at 10-7 M, while the acoustic sensor exhibited more sensitivity to Hg2+ over the full range. The results highlight a new potential alternative to use microalgae EPSs as a sensitive coating material for the detection of heavy metals. However, its use in a real liquid medium requires further investigation of its selectivity in the presence of other compounds.


Assuntos
Mercúrio , Metais Pesados , Microalgas , Cádmio/química , Matriz Extracelular de Substâncias Poliméricas , Mercúrio/química
12.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679749

RESUMO

Fruit classification is required in many smart-farming and industrial applications. In the supermarket, a fruit classification system may be used to help cashiers and customer to identify the fruit species, origin, ripeness, and prices. Some methods, such as image processing and NIRS (near-infrared spectroscopy) are already used to classify fruit. In this paper, we propose a fast and cost-effective method based on a low-cost Vector Network Analyzer (VNA) device augmented by K-nearest neighbor (KNN) and Neural Network model. S-parameters features are selected, which take into account the information on signal amplitude or phase in the frequency domain, including reflection coefficient S11 and transmission coefficient S21. This approach was experimentally tested for two separate datasets of five types of fruits, including Apple, Avocado, Dragon Fruit, Guava, and Mango, for fruit recognition as well as their level of ripeness. The classification accuracy of the Neural Network model was higher than KNN with 98.75% and 99.75% on the first dataset, whereas the KNN was seen to be more effective in classifying ripeness with 98.4% as compared to 96.6% for neural network.


Assuntos
Frutas , Redes Neurais de Computação , Frutas/química , Aprendizado de Máquina , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise por Conglomerados , Máquina de Vetores de Suporte
13.
Sensors (Basel) ; 23(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36679780

RESUMO

Aiming at guiding agricultural producers to harvest crops at an appropriate time and ensuring the pesticide residue does not exceed the maximum limit, the present work proposed a method of detecting pesticide residue rapidly by analyzing near-infrared microscopic images of the leaves of Shanghaiqing (Brassica rapa), a type of Chinese cabbage with computer vision technology. After image pre-processing and feature extraction, the pattern recognition methods of K nearest neighbors (KNN), naïve Bayes, support vector machine (SVM), and back propagation artificial neural network (BP-ANN) were applied to assess whether Shanghaiqing is sprayed with pesticides. The SVM method with linear or RBF kernel provides the highest recognition accuracy of 96.96% for the samples sprayed with trichlorfon at a concentration of 1 g/L. The SVM method with RBF kernel has the highest recognition accuracy of 79.16~84.37% for the samples sprayed with cypermethrin at a concentration of 0.1 g/L. The investigation on the SVM classification models built on the samples sprayed with cypermethrin at different concentrations shows that the accuracy of the models increases with the pesticide concentrations. In addition, the relationship between the concentration of the cypermethrin sprayed and the image features was established by multiple regression to estimate the initial pesticide concentration on the Shanghaiqing leaves. A pesticide degradation equation was established on the basis of the first-order kinetic equation. The time for pesticides concentration to decrease to an acceptable level can be calculated on the basis of the degradation equation and the initial pesticide concentration. The present work provides a feasible way to rapidly detect pesticide residue on Shanghaiqing by means of NIR microscopic image technique. The methodology laid out in this research can be used as a reference for the pesticide detection of other types of vegetables.


Assuntos
Resíduos de Praguicidas , Praguicidas , Resíduos de Praguicidas/análise , Teorema de Bayes , Verduras/química
14.
Curr Microbiol ; 80(2): 78, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36651991

RESUMO

A novel Gram-stain-negative, aerobic, irregular coccus designated as ZY201224T, was isolated from the nasal cavity of a goat with respiratory disease in a goat farm, located at Jianshui, Yunnan Province, PR China and its taxonomic position was clarified using a polyphasic approach. The strain grew optimally at 37 °C, at pH 8.0 and in the presence of 1% NaCl. Phylogenetic analysis based on 16S rRNA gene sequence and phylogenomic analysis based on 808 single-copy genes revealed that the strain is affiliated to the genus Moraxella and is distinct from the recognized species of the genus. The 16S rRNA gene sequence similarity analysis indicated that the strain is most closely related to Moraxella caviae CCUG 355T with sequence similarity of 98.1%. The genomic OrthoANI and digital DNA-DNA hybridization (dDDH) values between the strain and the type strains of Moraxella species were no higher than 74.7% (Moraxella pluranimalium CCUG 54913T) and 26.0% (Moraxella oblonga NBRC 102422T), respectively. The G + C content of the complete genome sequence was 43.6 mol%. The strain contained CoQ-8 as the major respiratory quinone, and C18:1ω9c, C17:1ω8c, C16:0 and summed feature 3 (C16:1 ω7c and/ or C16:1ω6c) as the predominant fatty acids (> 5%). The major polar lipids comprised phosphatidylglycerol (PG), cardiolipin (CL), monolysocardiolipin (MLCL), phosphatidylethanolamine (PE) and lysophosphatidylglycerol (LPG). Based on these taxonomic characterizations, strain ZY201224T represents a novel species of the genus Moraxella, for which the name Moraxella nasicaprae sp. nov. is proposed. The type strain is ZY201224T (= CCTCC AB 2021474T = NBRC 115473T).


Assuntos
Cabras , Fosfolipídeos , Animais , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Ubiquinona/química , Análise de Sequência de DNA , China , Ácidos Graxos/química , DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Hibridização de Ácido Nucleico
15.
Nat Commun ; 14(1): 383, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693847

RESUMO

Differential sensing attempts to mimic the mammalian senses of smell and taste to identify analytes and complex mixtures. In place of hundreds of complex, membrane-bound G-protein coupled receptors, differential sensors employ arrays of small molecules. Here we show that arrays of computationally designed de novo peptides provide alternative synthetic receptors for differential sensing. We use self-assembling α-helical barrels (αHBs) with central channels that can be altered predictably to vary their sizes, shapes and chemistries. The channels accommodate environment-sensitive dyes that fluoresce upon binding. Challenging arrays of dye-loaded barrels with analytes causes differential fluorophore displacement. The resulting fluorimetric fingerprints are used to train machine-learning models that relate the patterns to the analytes. We show that this system discriminates between a range of biomolecules, drink, and diagnostically relevant biological samples. As αHBs are robust and chemically diverse, the system has potential to sense many analytes in various settings.


Assuntos
Peptídeos , Olfato , Peptídeos/química , Conformação Proteica em alfa-Hélice
16.
Sci Rep ; 13(1): 1321, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693888

RESUMO

Ratiometric green-red fluorescent nanosensors for fluorometrically monitoring pH in the acidic range were designed from 80 nm-sized polystyrene (PS) and silica (SiO2) nanoparticles (NPs), red emissive reference dyes, and a green emissive naphthalimide pH probe, analytically and spectroscopically characterized, and compared regarding their sensing performance in aqueous dispersion and in cellular uptake studies. Preparation of these optical probes, which are excitable by 405 nm laser or LED light sources, involved the encapsulation of the pH-inert red-fluorescent dye Nile Red (NR) in the core of self-made carboxylated PSNPs by a simple swelling procedure and the fabrication of rhodamine B (RhB)-stained SiO2-NPs from a silane derivative of pH-insensitive RhB. Subsequently, the custom-made naphthalimide pH probe, that utilizes a protonation-controlled photoinduced electron transfer process, was covalently attached to the carboxylic acid groups at the surface of both types of NPs. Fluorescence microscopy studies with the molecular and nanoscale optical probes and A549 lung cancer cells confirmed the cellular uptake of all probes and their penetration into acidic cell compartments, i.e., the lysosomes, indicated by the switching ON of the green naphthalimide fluorescence. This underlines their suitability for intracellular pH sensing, with the SiO2-based nanosensor revealing the best performance regarding uptake speed and stability.


Assuntos
Nanopartículas , Dióxido de Silício , Dióxido de Silício/química , Poliestirenos , Naftalimidas , Corantes Fluorescentes/química , Nanopartículas/química , Concentração de Íons de Hidrogênio
17.
Drug Deliv ; 30(1): 2168793, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36694964

RESUMO

Guava (Psidium guajava L.) is a well-known plant containing high levels of natural antioxidants, the phenolic compounds, which have been employed in numerous cosmetic products. However, these molecules are unstable to oxidants, light, temperature, pH, water, and enzymatic activities. Therefore, to enhance their stability and preserve their antioxidant activity, this study investigated the silk fibroin nanoparticles (SFNs) ability to encapsulate, deliver, and heat-protect the phenolic compounds of the guava leaves ethanolic extract. Firstly, the guava ethanolic extract was produced by maceration, which possessed a total phenolic content of 312.6 mg GAE/g DPW and a high antioxidant activity (IC50 = 5.397 ± 0.618 µg/mL). Then, the extract loaded SFNs were manufactured by desolvation method, and the particles demonstrated appropriate sizes of 200-700 nm with narrow size distribution, spherical shape, silk-II crystalline structure, high drug entrapment efficiency of > 70% (dependent on the fibroin content), and a two-phase sustained drug release for at least 210 min. Using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the antioxidant activity of the guava extract was well-preserved in the extract loaded SFNs. Finally, after being treated with high temperature of 70 °C for 24 h, the guava extract almost loses all of its antioxidant property (5 times decrement), whereas the extract loaded SFNs could retain the extract activity. Conclusively, the SFNs proved much potential to deliver and heat-protect the guava extract phenolic compounds, and preserve their antioxidant activity. Confirmed by this case, SFNs could be further explored in protecting other natural compounds from environmental factors.


Assuntos
Fibroínas , Nanopartículas , Psidium , Antioxidantes/química , Psidium/química , Seda , Fenóis , Extratos Vegetais/química , Folhas de Planta/química
18.
J Enzyme Inhib Med Chem ; 38(1): 2166040, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36695002

RESUMO

Alzheimer disease (AD) is one of the major neurodegenerative diseases that could not be prevented or completely cured and may lead to death. Here, we target AChE and ß-amyloid proteins. Synthesising new triphenylphosphporanylidene derivatives based on the surveyed literature and testing their biological activity revealed promising results especially for the acetyl triphenylphosphoranylidene derivative 8c, which showed good inhibitor activity against AChE enzyme with IC50 in the nanomolar range (97.04 nM); on the other hand, it showed poor selectivity for AChE versus butyrylcholinesterase but with some futural structural modification, this selectivity can be improved. 8c showed MMP-2 IC50 of 724.19 nM and Aß1-42 aggregation IC50 of 302.36 nM. A kinetic study demonstrated that compound 8c uncompetitively inhibited AChE. Moreover, derivative 8c showed low cytotoxicity, good in vivo behavioural studies including Y-maze and passive avoidance tests with activity similar to that of donepezil. Finally, in silico studies for 8c predict its good penetration into BBB and good binding affinity in the AChE binding site.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Ligantes , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
19.
J R Soc Interface ; 20(198): 20220803, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36695019

RESUMO

Mineralized collagen fibrils (MCFs) comprise collagen molecules and hydroxyapatite (HAp) crystals and are considered universal building blocks of bone tissue, across different bone types and species. In this study, we developed a coarse-grained molecular dynamics (CGMD) framework to investigate the role of mineral arrangement on the load-deformation behaviour of MCFs. Despite the common belief that the collagen molecules are responsible for flexibility and HAp minerals are responsible for stiffness, our results showed that the mineral phase was responsible for limiting collagen sliding in the large deformation regime, which helped the collagen molecules themselves undergo high tensile loading, providing a substantial contribution to the ultimate tensile strength of MCFs. This study also highlights different roles for the mineralized and non-mineralized protofibrils within the MCF, with the mineralized groups being primarily responsible for load carrying due to the presence of the mineral phase, while the non-mineralized groups are responsible for crack deflection. These results provide novel insight into the load-deformation behaviour of MCFs and highlight the intricate role that both collagen and mineral components have in dictating higher scale bone biomechanics.


Assuntos
Colágeno , Simulação de Dinâmica Molecular , Colágeno/química , Osso e Ossos , Matriz Extracelular , Fenômenos Biomecânicos , Minerais/química
20.
Sci Rep ; 13(1): 1397, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36697465

RESUMO

Fibre-reinforced biocomposites usage has gained prominence over the past decade. Although higher fracture toughness was observed when fibres were added to biocomposites, material degradation could occur due to filler and fibre content intolerance in the biocomposite matrix. Optimisation of resin-fibre-filler ratios helps in increasing the tribological performance of high load-bearing applications. However, the tribological performance is less understood due to limited in-vitro studies on the effect of fibre microstructures. A comprehensive investigation of the reciprocating and rotary wear behaviour of different compositions was carried out by varying fibre (0%, 5%, 10% and 15%) to particulate filler (40%, 45%, 50%, and 55%) weight fractions. The investigation aimed to identify the optimal composition of fibre-reinforced biocomposites based on the in-vitro ball-on-disc reciprocating and rotary wear tests in the presence of modified Fusayama solution. The cross-sectional areas of wear tracks were analysed using laser microscopy and scanning electron microscopy techniques to assess the surface morphology and subsurface damage of the wear tracks on biocomposites and the antagonist. The numerical results were statistically analysed using two-way ANOVA followed by a posthoc Tukey's test (p = 0.05). The results showed a combination of adhesive, abrasive and fatigue wear for all the tested Groups. The friction coefficient had a longer transient period for the 5 wt% and 10 wt% Groups. Based on the surface roughness, coefficient of friction, SEMs, specific wear rate, and ease of manufacturing, the threshold limit for fibre loading was found to be 10 wt%. The rotary test had a considerably lower specific wear rate compared to the reciprocating test. Fibre weight fraction was found to be the influencing factor of the abrasive wear behaviour compared to fibre length for the tested Groups.


Assuntos
Vidro , Teste de Materiais , Fricção , Vidro/química , Suporte de Carga
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