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1.
Int J Biol Macromol ; 277(Pt 4): 134085, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39126981

RESUMO

A comparative study was performed to investigate the physicochemical properties and protective effects of hydrochloric acid-resistant dextrin (H-RD), citric acid-resistant dextrin (C-RD) and tartaric acid-resistant dextrin (T-RD) on the metabolic disorders and intestinal microbiota for type 2 diabetes mellitus (T2DM) mice. T-RD had the minimum molecular weight, with the highest short chain (DP 6-12) proportion and resistant starch content. After 4-week intervention with the three resistant dextrins, the body weight and fasting blood glucose of T2DM mice were improved significantly, accompanied by the reduction of serum indexes (TG, TC, LDL-C, ALT, AST, CRE, BUN, FINS, and GSP), but the serum HDL-C and liver glycogen levels increased. Among the three RDs intervention groups, T-RD showed the most significant improvement, followed by C-RD and finally H-RD. The 16 s rDNA results indicated that oral administration of resistant dextrins favored the proliferation of specific gut microbiota, including Faecalibaculum, Parabacteroides and Dubosiella, and reduced the ratio of Firmicutes/Bacteroidota, which is beneficial for reducing insulin resistance. Herein, the findings supported that the resistant dextrins exhibited a remission effect on T2DM, providing a basis for the development of functional food adjuvants for T2DM treatment.


Assuntos
Glicemia , Dextrinas , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Dieta Hiperlipídica , Microbioma Gastrointestinal , Hipoglicemiantes , Animais , Dextrinas/farmacologia , Dextrinas/química , Camundongos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Masculino , Administração Oral , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Estreptozocina , Peso Corporal/efeitos dos fármacos , Resistência à Insulina , Ácidos/química
2.
Food Chem ; 460(Pt 3): 140748, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142209

RESUMO

In this study, a novel dextrin-based micelle (OSAD-SH), dual-modified with octenyl succinic anhydride (OSA) and cysteamine, was developed to address the acid instability issues of micelle modified only by OSA and designed for curcumin delivery. Three amphiphilic OSAD-SH polymers with different free sulfhydryl content were first synthesized. The study demonstrated that OSAD-SH micelles exhibited strong self-assembly properties, appearing as spheres with diameters ranging from 92.41 to 194.20 nm. Blank micelles showed good dilution resistance, as well as stability against acid, thermal, and ionic strength. The curcumin encapsulated by the micelles was in an amorphous state. In vitro release experiment demonstrated that curcumin released from OSAD-SH micelles exhibited pH responsiveness. The Ritger-Peppas model effectively predicted the release behavior of curcumin, which followed a super case-II transport. The OSAD-SH micelle will be a promising nanocarrier for improving the physicochemical properties of curcumin in food fields.


Assuntos
Curcumina , Cisteamina , Dextrinas , Portadores de Fármacos , Micelas , Curcumina/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Dextrinas/química , Cisteamina/química , Anidridos Succínicos/química , Sistemas de Liberação de Medicamentos , Tamanho da Partícula
3.
Int J Biol Macromol ; 277(Pt 2): 134183, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39112113

RESUMO

The physico-chemical and biological properties of natural rubber latex (NRL), entailing its biodegradability and biocompatibility, render it a promising material for various biomedical applications. This research explores the facile blending of NRL with dextrin in different compositions to investigate its potential as a prospective UV shielding transdermal patch for biomedical applications. The superior compatibility between the polymers after blending and the improved thermal stability have been established through FTIR, DSC, and TGA examinations, respectively. Optimization of blended polymers for compatibility, wettability, crystallinity, and static mechanical properties has been performed. Morphology characterization conducted via SEM and AFM techniques suggests a uniform morphology for the optimized blend system. The UV shielding ability of the blend has been confirmed by the evaluation of in-vitro UV shielding performance, UV protection factor (UPF), and the superior protection of the optimized system on living cells upon UV irradiation. The observed cell viability, swelling, erosion, porosity, hemocompatibility, and soil degradation properties suggest the NRL-DXT combination for the possible development of high-quality transdermal patches.


Assuntos
Materiais Biocompatíveis , Dextrinas , Látex , Borracha , Adesivo Transdérmico , Raios Ultravioleta , Dextrinas/química , Materiais Biocompatíveis/química , Borracha/química , Látex/química , Humanos , Sobrevivência Celular/efeitos dos fármacos
4.
Biosci Biotechnol Biochem ; 88(10): 1180-1187, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38992276

RESUMO

Starch degradation in malted barley produces yeast-fermentable sugars. In this study, we compared the amylolytic enzymes and composition of the malt starch hydrolysates of two barley cultivars, Hokudai 1 (the first cultivar established in Japan) and Kitanohoshi (the currently used cultivar for beer production). Hokudai 1 malt contained lower activity of amylolytic enzymes than Kitanohoshi malt, although these cultivars contained α-amylase AMY2 and ß-amylase Bmy1 as the predominant enzymes. Malt starch hydrolysate of Hokudai 1 contained more limit dextrin and less yeast-fermentable sugars than that of Kitanohoshi. In mixed malt saccharification, a high Hokudai 1 malt ratio increased the limit dextrin levels and decreased the maltotriose and maltose levels. Even though Kitanohoshi malt contained more amylolytic enzymes than Hokudai 1 malt, addition of Kitanohoshi extract containing the amylolytic enzymes did not enhance malt starch degradation of Hokudai 1. Hokudai 1 malt starch was less degradable than Kitanohoshi malt starch.


Assuntos
Cerveja , Dextrinas , Hordeum , Maltose , Amido , alfa-Amilases , beta-Amilase , Hordeum/química , Hordeum/metabolismo , Hordeum/enzimologia , Amido/metabolismo , Cerveja/análise , alfa-Amilases/metabolismo , Hidrólise , Maltose/metabolismo , beta-Amilase/metabolismo , Japão , Dextrinas/metabolismo , Trissacarídeos/metabolismo , Fermentação
5.
Nutrients ; 16(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39064763

RESUMO

Developing modified dietary fibers that maintain prebiotic benefits without significantly affecting meal taste is of high importance in the midst of the obesity pandemic. These benefits include regulating the composition of gut microbiota, increasing feelings of fullness, and improving human metabolic parameters. This study investigated the use of a resistant dextrin (RD) derived from potato starch, which possesses prebiotic properties, as a potential additive in vegetable-fruit preparations that aid weight loss and improve health markers in overweight children. HPLC was employed to examine metabolites like lactic acid, short-chain fatty acids (SCFAs; formic, acetic, propionic, butyric, and valeric acids), and branched-chain fatty acids (BCFAs; isobutyric and isovaleric acids). The activities of α-glucosidase, ß-glucosidase, α-galactosidase, ß-galactosidase, and ß-glucuronidase enzymes in fecal samples were measured using spectrophotometric analysis at a wavelength of 400 nm. Incorporating the RD into vegetable-fruit preparations yielded favorable outcomes in terms of increased concentrations of the tested metabolites (SCFAs and BCFAs) and enhanced fecal enzyme activities after 6 months of consuming the preparations. Furthermore, these effects were found to last for an extended period of 3 months even after discontinuing the treatment. The study has shown that including RD into vegetable-fruit preparations enhances the metabolic parameters of obese and overweight children, hence providing a strong rationale for the widespread usage of these preparations in the industry.


Assuntos
Dextrinas , Fezes , Frutas , Prebióticos , Solanum tuberosum , Humanos , Solanum tuberosum/química , Criança , Masculino , Feminino , Frutas/química , Fezes/química , Obesidade Infantil , Alimentos Fortificados , Verduras , Microbioma Gastrointestinal , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/metabolismo , Sobrepeso , Amido , Amido Resistente
6.
Int J Nanomedicine ; 19: 5419-5437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38868592

RESUMO

Introduction: Acute myeloid leukemia (AML) remains difficult to treat due to its heterogeneity in molecular landscape, epigenetics and cell signaling alterations. Precision medicine is a major goal in AML therapy towards developing agents that can be used to treat patients with different 'subtypes' in combination with current chemotherapies. We have previously developed dextrin-colistin conjugates to combat the rise in multi-drug resistant bacterial infections and overcome dose-limiting nephrotoxicity. Recent evidence of colistin's anticancer activity, mediated through inhibition of intracellular lysine-specific histone demethylase 1 (LSD1/KDM1A), suggests that dextrin-colistin conjugates could be used to treat cancer cells, including AML. This study aimed to evaluate whether dextrin conjugation (which reduces in vivo toxicity and prolongs plasma half-life) could enhance colistin's cytotoxic effects in myeloid leukemia cell lines and compare the intracellular uptake and localization of the free and conjugated antibiotic. Results: Our results identified a conjugate (containing 8000 g/mol dextrin with 1 mol% succinoylation) that caused significantly increased toxicity in myeloid leukemia cells, compared to free colistin. Dextrin conjugation altered the mechanism of cell death by colistin, from necrosis to caspase 3/7-dependent apoptosis. In contrast, conjugation via a reversible ester linker, instead of an amide, had no effect on the mechanism of the colistin-induced cell death. Live cell confocal microscopy of fluorescently labelled compounds showed both free and dextrin-conjugated colistins were endocytosed and co-localized in lysosomes, and increasing the degree of modification by succinoylation of dextrin significantly reduced colistin internalization. Discussion: Whilst clinical translation of dextrin-colistin conjugates for the treatment of AML is unlikely due to the potential to promote antimicrobial resistance (AMR) and the relatively high colistin concentrations required for anticancer activity, the ability to potentiate the effectiveness of an anticancer drug by polymer conjugation, while reducing side effects and improving biodistribution of the drug, is very attractive, and this approach warrants further investigation.


Assuntos
Apoptose , Colistina , Dextrinas , Colistina/farmacologia , Colistina/química , Colistina/farmacocinética , Dextrinas/química , Dextrinas/farmacologia , Humanos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/farmacocinética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Sobrevivência Celular/efeitos dos fármacos
7.
Int J Biol Macromol ; 270(Pt 1): 131889, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38782624

RESUMO

This work aimed at building functional emulsions based on the linear dextrins (LDs) emulsion system. The gradient polyethylene glycol (PEG) precipitaion method was used to fractionate LDs into fractions with different degrees of polymerization (DP). A package, and co-precipitation procedure of LDs, and eicosapentaenoic acid (EPA) was used to fabricate LDs-EPA composites. The gas chromatograph, Fourier transform infrared spectroscopy, X-ray diffraction and differential scanning calorimetry analyses affirmed the formation of the LDs-EPA composites. The sizes of these composites were 38.55 nm, 59.14 nm to 80.62 nm, respectively, and they had good amphiphilicity. Compared with LDs, these LDs-EPA composites stabilized Pickering emulsion had higher stability and antioxidant capacity. Their emulsifying ability was positively correlated with the DP values of LDs. Furthermore, the oxidation stability results showed that LDsF10-EPA emulsion had the lowest lipid hydroperoxide (LHs) content, malondioxide (MDA) content and hexal concentration, which were 138.75 mmol kg-1 oil, 15.50 mmol kg-1 oil and 3.83 µmol kg-1 oil, respectively. The study provided a new idea and application values for the application of LDs in emulsion.


Assuntos
Dextrinas , Ácido Eicosapentaenoico , Emulsões , Polimerização , Emulsões/química , Ácido Eicosapentaenoico/química , Ácido Eicosapentaenoico/análogos & derivados , Dextrinas/química , Antioxidantes/química , Emulsificantes/química , Polietilenoglicóis/química , Difração de Raios X
8.
Talanta ; 274: 126016, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38599118

RESUMO

The present study investigates the use of dextrins (maltodextrin, ß-cyclodextrin, and hydroxypropyl-ß-cyclodextrin) to improve the efficiency of the agarose-based gel electromembrane extraction technique for extracting chiral basic drugs (citalopram, hydroxyzine, and cetirizine). Additionally, it examines the enantioselectivity of the extraction process for these drugs. To achieve these, dextrins were incorporated into either the sample solution, the membrane, or the acceptor solution, and then the extraction procedure was performed. Enantiomers were separated and analyzed using a capillary electrophoresis device equipped with a UV detector. The results obtained under the optimal extraction conditions (sample solution pH: 4.0, acceptor solution pH: 2.0, gel membrane pH: 3.0, agarose concentration: 3 % w/v, stirring rate: 1000 rpm, gel thickness: 4.4 mm, extraction voltage: 62.3 V, and extraction time: 32.1 min) indicated that incorporating dextrins into either the sample solution, membrane or the acceptor solution enhances extraction efficiency by 17.3-23.1 %. The most significant increase was observed when hydroxypropyl-ß-cyclodextrin was added to the acceptor solution. The findings indicated that the inclusion of hydroxypropyl-ß-cyclodextrin in the sample solution resulted in an enantioselective extraction, yielding an enantiomeric excess of 6.42-7.14 %. The proposed method showed a linear range of 5.0-2000 ng/mL for enantiomers of model drugs. The limit of detection and limit of quantification for all enantiomers were found to be < 4.5 ng/mL and <15.0 ng/mL, respectively. Intra- and inter-day RSDs (n = 4) were less than 10.8 %, and the relative errors were less than 3.2 % for all the enantiomers. Finally, the developed method was successfully applied to determine concentrations of enantiomers in a urine sample with relative recoveries of 96.8-99.2 %, indicating good reliability of the developed method.


Assuntos
Dextrinas , Géis , Membranas Artificiais , Estereoisomerismo , Dextrinas/química , Géis/química , Eletroforese Capilar/métodos , Hidroxizina/análise , Hidroxizina/isolamento & purificação , Hidroxizina/química , Hidroxizina/urina , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Cetirizina/química , Cetirizina/urina , Cetirizina/análise , Cetirizina/isolamento & purificação , Concentração de Íons de Hidrogênio , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Preparações Farmacêuticas/isolamento & purificação , Preparações Farmacêuticas/urina , Sefarose/química
9.
Nutrients ; 16(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38612951

RESUMO

BACKGROUND: The study investigated the impact of starch degradation products (SDexF) as prebiotics on obesity management in mice and overweight/obese children. METHODS: A total of 48 mice on a normal diet (ND) and 48 on a Western diet (WD) were divided into subgroups with or without 5% SDexF supplementation for 28 weeks. In a human study, 100 overweight/obese children were randomly assigned to prebiotic and control groups, consuming fruit and vegetable mousse with or without 10 g of SDexF for 24 weeks. Stool samples were analyzed for microbiota using 16S rRNA gene sequencing, and short-chain fatty acids (SCFA) and amino acids (AA) were assessed. RESULTS: Results showed SDexF slowed weight gain in female mice on both diets but only temporarily in males. It altered bacterial diversity and specific taxa abundances in mouse feces. In humans, SDexF did not influence weight loss or gut microbiota composition, showing minimal changes in individual taxa. The anti-obesity effect observed in mice with WD-induced obesity was not replicated in children undergoing a weight-loss program. CONCLUSIONS: SDexF exhibited sex-specific effects in mice but did not impact weight loss or microbiota composition in overweight/obese children.


Assuntos
Obesidade Infantil , Solanum tuberosum , Criança , Humanos , Masculino , Feminino , Animais , Camundongos , Dextrinas , Dieta Ocidental , Disbiose , Sobrepeso , RNA Ribossômico 16S/genética , Peso Corporal , Amido/farmacologia , Frutas
10.
Food Chem ; 448: 139043, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38552463

RESUMO

This study aimed to evaluate the potential of the bilayer emulsions stabilized with casein/butyrylated dextrin nanoparticles and chitosan as fat substitutes in preparing low-calorie sponge cakes. Among the different cake groups, the substitution of bilayer emulsions at 60% exhibited comparable baking properties, appearance, texture characteristics and stable secondary structure to fat. The specific volume and height were increased by 36.94% and 22%, respectively, while the cake showed higher lightness (L*) in the cores and softer hardness in the crumb. In addition, the moisture content of cakes was increased while the water activity remained unchanged. These results showed that casein/butyrylated dextrin bilayer emulsion was a potential fat substitute for cake products at the ratio of 60% with the desirable characteristics.


Assuntos
Caseínas , Quitosana , Dextrinas , Emulsões , Substitutos da Gordura , Nanopartículas , Quitosana/química , Nanopartículas/química , Caseínas/química , Dextrinas/química , Emulsões/química , Substitutos da Gordura/química , Culinária
11.
Int J Biol Macromol ; 266(Pt 1): 131160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547946

RESUMO

In present study, bilayer emulsions with different interfacial structures stabilized by casein/butyrylated dextrin nanoparticles (CDNP), chitosan (CS) and chitosan nanoparticles (CSNP) were prepared to overcome the limitations of conventional emulsions. The effects of chitosan morphology and incorporation sequences on the bilayer emulsions were examined. Bilayer emulsions prepared with CDNP as the inner layer and CS/CSNP as the outer layer were observed to have smaller droplet sizes (1.39 ± 86.74 um and 1.45 ± 7.87 um). Bilayer emulsions prepared with CDNP as the inner layer and CS as the outer layer exhibited the lowest creaming index (2.38 %) after 14 days of storage, indicating excellent stability. Furthermore, bilayer emulsion prepared with CDNP as the inner layer and CS as the outer layer also exhibited a uniform water distribution, excellent protein oxidative stability, and uniformly distributed droplets by the measurement of Low-field NMR, intrinsic tryptophan fluorescence and laser confocal laser scanning microscopy. These results indicated that the study provided a theoretical basis for the development and design of bilayer emulsions with different interfacial structures. This study also provides a new material for the preparation of delivery systems that protect biologically active compounds. Bilayer emulsions are promising for applications in traditional and manufactured food products.


Assuntos
Caseínas , Quitosana , Dextrinas , Emulsões , Nanopartículas , Quitosana/química , Caseínas/química , Emulsões/química , Nanopartículas/química , Dextrinas/química , Tamanho da Partícula
12.
ACS Biomater Sci Eng ; 10(4): 2510-2522, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38466622

RESUMO

Theranostic systems, which integrate therapy and diagnosis into a single platform, have gained significant attention as a promising approach for noninvasive cancer treatment. The field of image-guided therapy has revolutionized real-time tumor detection, and within this domain, plasmonic nanostructures have garnered significant attention. These structures possess unique localized surface plasmon resonance (LSPR), allowing for enhanced absorption in the near-infrared (NIR) range. By leveraging the heat generated from plasmonic nanoparticles upon NIR irradiation, target cancer cells can be effectively eradicated. This study introduces a plasmonic gold dogbone-nanorattle (AuDB NRT) structure that exhibits broad absorption in the NIR region and demonstrates a photothermal conversion efficiency of 35.29%. When exposed to an NIR laser, the AuDB NRTs generate heat, achieving a maximum temperature rise of 38 °C at a concentration of 200 µg/mL and a laser power density of 3 W/cm2. Additionally, the AuDB NRTs possess intrinsic electromagnetic hotspots that amplify the signal of a Raman reporter molecule, making them an excellent probe for surface-enhanced Raman scattering-based bioimaging of cancer cells. To improve the biocompatibility of the nanorattles, the AuDB NRTs were conjugated with mPEG-thiol and successfully encapsulated into cationic dextrin nanoparticles (CD NPs). Biocompatibility tests were performed on HEK 293 A and MCF-7 cell lines, revealing high cell viability when exposed to AuDB NRT-CD NPs. Remarkably, even at a low laser power density of 1 W/cm2, the application of the NIR laser resulted in a remarkable 80% cell death in cells treated with a nanocomposite concentration of 100 µg/mL. Further investigation elucidated that the cell death induced by photothermal heat followed an apoptotic mechanism. Overall, our findings highlight the significant potential of the prepared nanocomposite for cancer theranostics, combining effective photothermal therapy along with the ability to image cancer cells.


Assuntos
Nanocompostos , Nanopartículas , Neoplasias , Humanos , Ouro/farmacologia , Ouro/química , Dextrinas , Nanomedicina Teranóstica/métodos , Células HEK293 , Nanopartículas/uso terapêutico , Neoplasias/terapia
13.
Biotechnol Prog ; 40(3): e3443, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38462773

RESUMO

In this investigation, low molecular weight polyethyleneimine (LMW PEI; 1.8 kDa branched PEI) was conjugated to phathalated dextrin. The aim of this chemical modification was to decorate PEI molecules with a hydrophilic layer to improve its biophysical properties while the phthalic moiety may improve the hydrophilic-hydrophobic balance of the final structure. The polymers were prepared at various conjugation degrees ranging from 6.5% to 16.5% and characterized in terms of biophysical characteristics as well as their gene transfer ability and cell-induced toxicity. The results showed that dextrin-phthalated-PEI (DPHPEI) polymer was able to form nanoparticles with the size range of around 118-170 nm, with the zeta potential of 6.2-9.5 mV. DPHPEI polymers could increase the level of desired protein expression in the cells by up to three folds compared with unmodified LMW PEI while the cell viability of the modified polymers was around 80%. The result of this study shows a promising approach to improve the transfection efficiency of LMW PEI while maintaining its low toxic effects.


Assuntos
Dextrinas , Interleucina-12 , Plasmídeos , Polietilenoimina , Humanos , Sobrevivência Celular/efeitos dos fármacos , Dextrinas/química , Técnicas de Transferência de Genes , Interleucina-12/genética , Interleucina-12/metabolismo , Interleucina-12/química , Peso Molecular , Tamanho da Partícula , Plasmídeos/genética , Plasmídeos/química , Polietilenoimina/química , Transfecção/métodos
14.
J Biochem ; 176(2): 109-117, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38498909

RESUMO

Glycogen debranching enzyme is a single polypeptide with distinct catalytic sites for 4-α-glucanotransferase and amylo-α-1,6-glucosidase. To allow phosphorylase to degrade the inner tiers of highly branched glycogen, 4-α-glucanotransferase converts the phosphorylase-limit biantennary branch G-G-G-G-(G-G-G-G↔)G-G- (G: d-glucose, hyphens: α-1,4-linkages; double-headed arrow: α-1,6-linkage) into the G-G-G-G-(G↔)G-G- residue, which is then subjected to amylo-α-1,6-glucosidase to release the remaining G↔ residue. However, while the essential side-chain structure of the 4-α-glucanotransferase donor substrate has been determined to be the G-G-G-G↔ residue (Watanabe, Y., et al. (2008) J. Biochem.143, 435-440), its essential main-chain structure remains to be investigated. In this study, we probed the 4-α-glucanotransferase donor-binding region using novel fluorogenic dextrins Gm-(G4↔)G-Gn-F (F: 1-deoxy-1-[(2-pyridyl)amino]-d-glucitol) and maltohexaose (G6) as the donor and acceptor substrates, respectively. 4-α-Glucanotransferase exhibited maximum activity towards G4-(G4↔)G-F and G4-(G4↔)G-G-F, indicating that recognition of the G4-(G4↔)G-moiety was essential for full enzyme function. Notably, when the 4-α-glucanotransferase activity towards G4-(G4↔)G-G-F was taken as unity, those towards nonbranching dextrins were < 0.001. This indicated that the disproportionation activities towards maltooligosaccharides (Gm) are abnormal behaviours of 4-α-glucanotransferase. Notably, however, these activities have been traditionally measured to identify the 4-α-glucanotransferase mutations causing glycogen storage disease type III. This study provides a basis for more accurate identification.


Assuntos
Dextrinas , Sistema da Enzima Desramificadora do Glicogênio , Sistema da Enzima Desramificadora do Glicogênio/metabolismo , Sistema da Enzima Desramificadora do Glicogênio/química , Sistema da Enzima Desramificadora do Glicogênio/genética , Dextrinas/metabolismo , Dextrinas/química , Especificidade por Substrato
15.
Macromol Rapid Commun ; 45(12): e2400059, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38538294

RESUMO

Many crucial components inside electronic devices are made from non-renewable, non-biodegradable, and potentially toxic materials, leading to environmental damage. Finding alternative green dielectric materials is mandatory to align with global sustainable goals. Carboxymethyl cellulose (CMC) is a bio-polymer derived from cellulose and has outstanding properties. Herein, citric acid, dextrin, and CMC based hydrogels are prepared, which are biocompatible and biodegradable and exhibit rubber-like mechanical properties, with Young modulus values of 0.89 MPa. Hence, thin film CMC-based hydrogel is explored as a suitable green high-k dielectric candidate for operation at low voltages, demonstrating a high dielectric constant of up to 78. These fabricated transistors reveal stable high capacitance (2090 nF cm-2) for ≈±3 V operation. Using a polyelectrolyte-type approach and poly-(2-vinyl anthracene) (PVAn) surface modification, this study demonstrates a thin dielectric layer (d ≈30 nm) with a small voltage threshold (Vth ≈-0.8 V), moderate transconductance (gm ≈65 nS), and high ON-OFF ratio (≈105). Furthermore, the dielectric layer exhibits stable performance under bias stress of ± 3.5 V and 100 cycles of switching tests. The modified CMC-based hydrogel demonstrates desirable performance as a green dielectric for low-voltage operation, further highlighting its biocompatibility.


Assuntos
Carboximetilcelulose Sódica , Dextrinas , Hidrogéis , Dextrinas/química , Carboximetilcelulose Sódica/química , Hidrogéis/química , Hidrogéis/síntese química , Materiais Biocompatíveis/química , Química Verde
16.
Ecotoxicol Environ Saf ; 273: 116120, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401200

RESUMO

The ability to employ waste products, such as vegetable scraps, as raw materials for the synthesis of new promising adsorbing materials is at the base of the circular economy and end of waste concepts. Dextrin-based nanosponges (D_NS), both cyclodextrin (CD) and maltodextrin (MD), have shown remarkable adsorption abilities in the removal of toxic compounds from water and wastewater, thus representing a bio-based low-cost solution which is establishing itself in the market. Nevertheless, their environmental safety for either aquatic or terrestrial organisms has been overlooked, raising concern in terms of potential hazards to natural ecosystems. Here, the environmental safety (ecosafety) of six newly synthesized batches of D_NS was determined along with their full characterization by means of dynamic light scattering (DLS), thermogravimetric analysis (TGA), Fourier transformed infrared spectroscopy with attenuated total reflection (FTIR-ATR) and transmission electron microscopy (SEM). Ecotoxicity evaluation was performed using a battery of model organisms and ecotoxicity assays, such as the microalgae growth inhibition test using the freshwater Raphidocelis subcapitata and the marine diatom Dunaliella tertiolecta, regeneration assay using the freshwater cnidarian Hydra vulgaris and immobilization assay with the marine brine shrimp Artemia franciscana. Impact on seedling germination of a terrestrial plant of commercial interest, Cucurbita pepo was also investigated. Ecotoxicity data showed mild to low toxicity of the six batches, up to 1 mg/mL, in the following order: R. subcapitata > H. vulgaris > D. tertiolecta > A. franciscana > C. pepo. The only exception was represented by one batch (NS-Q+_BDE_(GLU2) which resulted highly toxic for both freshwater species, R. subcapitata and H. vulgaris. Those criticalities were solved with the synthesis of a fresh new batch and were hence attributed to the single synthesis and not to the specific D_NS formulation. No effect on germination of pumpkin but rather more a stimulative effect was observed. To our knowledge this is the first evaluation of the environmental safety of D_ NS. As such we emphasize that current formulations and exposure levels in the range of mg/mL do not harm aquatic and terrestrial species thus representing an ecosafe solution also for environmental applications.


Assuntos
Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Dextrinas , Ecossistema , Plantas , Águas Residuárias/toxicidade , Artemia
17.
ACS Appl Mater Interfaces ; 16(9): 11860-11871, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38410836

RESUMO

In this research, we report dextrin-based biodegradable microgels (PDXE MGs) having phosphate-based cross-linking units for slow release of urea and a potential P source to improve fertilization. PDXE MGs (∼200 nm) are synthesized by cross-linking the lauroyl-functionalized dextrin chains with sodium tripolyphosphate. The developed PDXE MGs exhibit high loading (∼10%) and encapsulation efficiency (∼88%) for urea. It is observed that functionalization of PDXE MGs with lauroyl chains slows down the release of urea (90% in ∼24 days) as compared to nonfunctionalized microgels (PDX MGs) (99% in ∼17 days) in water. Further studies of the developed formulation display that Urea@PDXE MGs significantly boost maize seed germination and overall plant growth as compared to pure urea fertilizer. Moreover, analysis of maize leaves obtained from plants treated with Urea@PDXE MGs reveals 3.5 ± 0.3% nitrogen content and 90 ± 0.7 mg/g chlorophyll content. These values are significantly higher than 1.4 ± 0.6% nitrogen content and 48 ± 0.05 mg/g chlorophyll content obtained by using bare urea. Further, acid phosphatase activity in roots is reduced upon treatment with PDXE MGs and Urea@PDXE MGs, suggesting the availability of P upon degradation of PDXE MGs by the amylase enzyme in soil. These experimental results present the developed microgel-based biodegradable formulation with a slow release feature as a potential candidate to move toward sustainable agriculture practices.


Assuntos
Microgéis , Fertilizantes , Dextrinas , Agricultura , Solo , Nitrogênio , Ureia , Zea mays , Clorofila
18.
Biomolecules ; 14(2)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38397423

RESUMO

Systemic chronic inflammation is recognized as a significant contributor to the development of obesity-related insulin resistance. Previous studies have revealed the physiological benefits of resistant dextrin (RD), including obesity reduction, lower fasting glucose levels, and anti-inflammation. The present study investigated the effects of RD intervention on insulin resistance (IR) in Kunming mice, expounding the mechanisms through the gut microbiome and transcriptome of white adipose. In this eight-week study, we investigated changes in tissue weight, glucose-lipid metabolism levels, serum inflammation levels, and lesions of epididymal white adipose tissue (eWAT) evaluated via Hematoxylin and Eosin (H&E) staining. Moreover, we analyzed the gut microbiota composition and transcriptome of eWAT to assess the potential protective effects of RD intervention. Compared with a high-fat, high-sugar diet (HFHSD) group, the RD intervention significantly enhanced glucose homeostasis (e.g., AUC-OGTT, HOMA-IR, p < 0.001), and reduced lipid metabolism (e.g., TG, LDL-C, p < 0.001) and serum inflammation levels (e.g., IL-1ß, IL-6, p < 0.001). The RD intervention also led to changes in the gut microbiota composition, with an increase in the abundance of probiotics (e.g., Parabacteroides, Faecalibaculum, and Muribaculum, p < 0.05) and a decrease in harmful bacteria (Colidextribacter, p < 0.05). Moreover, the RD intervention had a noticeable effect on the gene transcription profile of eWAT, and KEGG enrichment analysis revealed that differential genes were enriched in PI3K/AKT, AMPK, in glucose-lipid metabolism, and in the regulation of lipolysis in adipocytes signaling pathways. The findings demonstrated that RD not only ameliorated IR, but also remodeled the gut microbiota and modified the transcriptome profile of eWAT.


Assuntos
Animais não Endogâmicos , Microbioma Gastrointestinal , Resistência à Insulina , Camundongos , Animais , Transcriptoma , Dextrinas/farmacologia , Triticum/metabolismo , Amido , Fosfatidilinositol 3-Quinases/metabolismo , Obesidade/metabolismo , Inflamação/genética , Glucose/farmacologia , Camundongos Endogâmicos C57BL
19.
Int J Biol Macromol ; 261(Pt 2): 129942, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311131

RESUMO

Arabinoxylans, ß-glucans, and dextrins influence the brewing industry's filtration process and product quality. Despite their relevance, only a maximum concentration of ß-glucans is recommended. Nevertheless, filtration problems are still present, indicating that although the chemical concentration is essential, other parameters should be investigated. Molar mass and conformation are important polymer physical characteristics often neglected in this industry. Therefore, this research proposes an approach to physically characterize enzymatically isolated beer polysaccharides by asymmetrical flow field-flow fractionation coupled to multi-angle light scattering and differential refractive index detector. Based on the obtained molar masses, root-mean-square radius (rrms from MALS), and hydrodynamic radius (rhyd), conformational properties such as apparent density (ρapp) and rrms/rhyd can be calculated based on their molar mass and size. Consequently, the ρapp and rrms/rhyd behavior hints at the different structures within each polysaccharide. The rrms/rhyd 1.2 and high ρapp values on low molar mass dextrins (1-2·105 g/mol) indicate branches, while aggregated structures at high molar masses on arabinoxylans and ß-glucans (2·105 -6·106 g/mol) are due to an increase of ρapp and a rrms/rhyd (0.6-1). This methodology provides a new perspective to analyze starch and non-starch polysaccharides in cereal-based beverages since different physical characteristics could influence beer's filtration and sensory characteristics.


Assuntos
Fracionamento por Campo e Fluxo , beta-Glucanas , Grão Comestível , Dextrinas , Polissacarídeos , Amido/química , Fracionamento por Campo e Fluxo/métodos , Espalhamento de Radiação
20.
Amino Acids ; 56(1): 14, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340233

RESUMO

Glycogen phosphorylase (GP) is biologically active as a dimer of identical subunits, each activated by phosphorylation of the serine-14 residue. GP exists in three interconvertible forms, namely GPa (di-phosphorylated form), GPab (mono-phosphorylated form), and GPb (non-phosphorylated form); however, information on GPab remains scarce. Given the prevailing view that the two GP subunits collaboratively determine their catalytic characteristics, it is essential to conduct GPab characterization to gain a comprehensive understanding of glycogenolysis regulation. Thus, in the present study, we prepared rabbit muscle GPab from GPb, using phosphorylase kinase as the catalyst, and identified it using a nonradioactive phosphate-affinity gel electrophoresis method. Compared with the half-half GPa/GPb mixture, the as-prepared GPab showed a unique AMP-binding affinity. To further investigate the intersubunit communication in GP, its catalytic site was probed using pyridylaminated-maltohexaose (a maltooligosaccharide-based substrate comprising the essential dextrin structure for GP; abbreviated as PA-0) and a series of specifically modified PA-0 derivatives (substrate analogs lacking part of the essential dextrin structure). By comparing the initial reaction rates toward the PA-0 derivative (Vderivative) and PA-0 (VPA-0), we demonstrated that the Vderivative/VPA-0 ratio for GPab was significantly different from that for the half-half GPa/GPb mixture. This result indicates that the interaction between the two GP subunits significantly influences substrate recognition at the catalytic sites, thereby providing GPab its unique substrate recognition profile.


Assuntos
Dextrinas , Glicogênio Fosforilase , Animais , Coelhos , Domínio Catalítico , Glicogênio Fosforilase/metabolismo , Músculos/metabolismo , Comunicação
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