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1.
Food Chem ; 462: 141023, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217742

RESUMO

Type II collagen (Col II) and chondroitin sulfate (CS) are the main macromolecules in the extracellular matrix. This study investigated the characteristics of Col II and CS obtained from chicken sternal cartilage (CSC) via enzymatic hydrolysis for various treatment times. For Col II and CS, the highest efficiency of enzymatic hydrolysis was achieved after 24 and 6 h of treatment, respectively. The average molecular weights were α1 chain-130 kDa, ß chain-270 kDa for Col II, and 80.27 kDa for CS. Fourier transform infrared spectroscopy revealed that the Col II samples maintained their triple-helical structure and that the predominant type of CS was chondroitin-4-sulfate. Scanning electron microscopy revealed that the Col II and CS samples possessed fibrillar and clustered structures, respectively. This study suggests that collagen and CS obtained from CSC can be used as promising molecules for application in food and pharmaceutical industries.


Assuntos
Cartilagem , Galinhas , Sulfatos de Condroitina , Colágeno Tipo II , Animais , Sulfatos de Condroitina/química , Sulfatos de Condroitina/isolamento & purificação , Cartilagem/química , Colágeno Tipo II/química , Colágeno Tipo II/metabolismo , Peso Molecular , Esterno/química , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Food Chem ; 462: 141024, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217751

RESUMO

With the aim of expanding the potential application scope of mulberries, eleven pH-switchable deep eutectic solvents were screened for the ultrasonic-assisted extraction of mulberry polysaccharides, and a salt/salt aqueous two-phase system was constructed for the efficient separation of mulberry polysaccharides by regulating the system pH. DES-9 (tetraethylammonium chloride: octanoic acid molar ratio = 1: 2) with a critical response pH value of approximately 6.1 was concluded to be the best extraction solvent for extracting mulberry polysaccharides. A maximum polysaccharide extraction yield of 270.71 mg/g was obtained under the optimal conditions. The maximum polysaccharide extraction efficiency was 78.09 % for the pH-driven tetraethylammonium chloride/K2HPO4 aqueous two-phase system. An acidic ß-pyran mulberry polysaccharide with a low-molecular weight of 9.26 kDa and a confirmed monosaccharide composition were obtained. This efficient and environmentally friendly polysaccharide separation method offers a new approach for the efficient extraction and utilization of other plant polysaccharides.


Assuntos
Solventes Eutéticos Profundos , Morus , Extratos Vegetais , Polissacarídeos , Morus/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Concentração de Íons de Hidrogênio , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Solventes Eutéticos Profundos/química , Fracionamento Químico/métodos , Peso Molecular , Frutas/química , Cloreto de Sódio/química
3.
Carbohydr Polym ; 346: 122582, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245481

RESUMO

The present study identified the protective effects of garlic oligo/poly-saccharides of different chain lengths against dextran sulfate sodium (DSS)-induced colitis in mice and elucidated the structure-function relationships. The results showed that oral intake of garlic oligo/poly-saccharides decreased disease activity index, reduced colon shortening and spleen enlargement, and ameliorated pathological damage in the mouse colon. The dysregulation of colonic pro/anti-inflammatory cytokines was significantly alleviated, accompanied by up-regulated antioxidant enzymes, blocked TLR4-MyD88-NF-κB signaling pathway, enhanced intestinal barrier integrity, and restored SCFA production. Garlic oligo/poly-saccharides also reversed gut microbiota dysbiosis in colitic mice by expanding beneficial bacteria and suppressing the growth of harmful bacteria. High-molecular-weight polysaccharides exhibited stronger alleviating effects on DSS-induced colitic symptoms in mice than low-molecular-weight oligo/poly-saccharides did, probably due to their greater ability to be fermented in the colon. Taken together, this study demonstrated the anti-inflammatory effects of garlic oligo/poly-saccharides and revealed that high-molecular-weight polysaccharide fractions were more effective in alleviating DSS-induced colitis.


Assuntos
Anti-Inflamatórios , Colite , Sulfato de Dextrana , Frutanos , Alho , Microbioma Gastrointestinal , Animais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Alho/química , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Frutanos/farmacologia , Frutanos/química , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Relação Estrutura-Atividade , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Peso Molecular , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Carbohydr Polym ; 346: 122657, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245513

RESUMO

Enterovirus 71 (EV71) is recognized as a major causative agent of hand, foot, and mouth disease (HFMD), posing a significant global public health concern due to its widespread impact and resulting in a major public health issue worldwide. Despite its prevalence, current clinical therapy lacks effective antiviral agents. Fucosylated chondroitin sulfates (FCS) derived from sea cucumber exhibits a range of biological activities including potent antiviral effects. This study provides compelling evidence of the potent antiviral efficacy of FCS against EV71. To further elucidate the impact of structural variations on the anti-EV71 activity, native FCSs with diverse sulfation patterns and a varity of FCS derivatives were prepared and analyzed. Notably, this study presents the detailed structural characterization of FCSs from the sea cucumbers Holothuria scabra Jaege and Holothuria fuscopunctata. Analysis of the structure-activity relationships revealed that molecular weight, sulfated fucose branches, and sulfation pattern were all crucial factors contributing to the potent inhibitory effects of FCS against EV71. Interestingly, molecular weight emerged as the most significant structural determinant of the antiviral potency. These findings suggest the promising potential of utilizing FCS as an innovative EV71 entry inhibitor for the treatment of HFMD.


Assuntos
Antivirais , Sulfatos de Condroitina , Enterovirus Humano A , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Antivirais/farmacologia , Antivirais/química , Animais , Enterovirus Humano A/efeitos dos fármacos , Relação Estrutura-Atividade , Humanos , Pepinos-do-Mar/química , Chlorocebus aethiops , Peso Molecular , Células Vero
5.
Carbohydr Polym ; 346: 122639, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245530

RESUMO

Molecular weight (Mw) of ligand-mediated nanocarriers plays a pivotal role in their architecture and properties. In this study, self-assembled ovalbumin (OVA)-loaded nanoparticles were meticulously engineered by starch polyelectrolytes with different Mw. Results unveiled that, tailoring Mw of GRGDS pentapeptides-grafted carboxymethyl starch (G-CMS) displayed strong binding-affinity and transport efficiency through microfold cells (M cells) pathway in the simulated intestinal epithelial cell monolayer in which M cells were randomly located in the Caco-2 cells monolayer. Notably, nanoparticles assembled from G-CMS with relatively higher Mw exhibited more compact structures due to the stronger interactions between layers compared to that with relatively lower Mw, which rendered remarkably stable and only 19.01 % in vitro OVA leakage under conditions of the upper gastrointestinal tract. Subsequently, more intact nanoparticles reached M cells after in vitro digestion and exhibited higher transport efficiency through the M cells pathways (apparent permeability: 9.38 × 10-5 cm/s) than Caco-2 cells, attributing to specific- and non-specific binding affinity towards M cells. Therefore, optimal Mw tailoring of starch polyelectrolytes can mediate the molecular interactions among their assembled layers and the interactions with M cells to balance the structural compactness, release and transport efficacy of nanoparticles, holding promise for advancing M cells-targeting oral delivery technologies.


Assuntos
Portadores de Fármacos , Peso Molecular , Nanopartículas , Amido , Humanos , Amido/química , Amido/análogos & derivados , Amido/metabolismo , Células CACO-2 , Nanopartículas/química , Portadores de Fármacos/química , Ovalbumina/química , Ovalbumina/metabolismo , Liberação Controlada de Fármacos , Transporte Biológico , Células M
7.
Carbohydr Polym ; 346: 122659, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245534

RESUMO

Implant-associated infection (IAI) is a prevalent and potentially fatal complication of orthopaedic surgery. Boosting antibacterial immunity, particularly the macrophage-mediated response, presents a promising therapeutic approach for managing persistent infections. In this study, we successfully isolated and purified a homogeneous and neutral water-soluble polysaccharide, designated as AM-1, from the edible fungus Agaricus blazei Murrill. Structure analysis revealed that AM-1 (Mw = 3.87 kDa) was a low-molecular-weight glucan characterized by a primary chain of →4)-α-D-Glcp-(1 â†’ and side chains that were linked at the O-6 and O-3 positions. In vivo assays showed that AM-1 effectively attenuated the progression of infection and mitigated infectious bone destruction in IAI mouse models. Mechanistically, AM-1 promotes intracellular autophagy-lysosomal biogenesis by inducing the nuclear translocation of transcription factor EB, finally enhancing the bactericidal capabilities and immune-modulatory functions of macrophages. These findings demonstrate that AM-1 significantly alleviates the progression of challenging IAIs as a presurgical immunoenhancer. Our research introduces a novel therapeutic strategy that employs natural polysaccharides to combat refractory infections.


Assuntos
Agaricus , Glucanos , Macrófagos , Animais , Camundongos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Agaricus/química , Glucanos/química , Glucanos/farmacologia , Células RAW 264.7 , Antibacterianos/farmacologia , Antibacterianos/química , Infecções Relacionadas à Prótese/tratamento farmacológico , Peso Molecular , Camundongos Endogâmicos C57BL , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos
8.
Carbohydr Polym ; 345: 122589, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227113

RESUMO

Maturity and drying treatment are important factors affecting the processing characteristics of lotus seeds and its starch. This study aimed to investigate the effect of maturity (from low to high-M-1, M-2, M-3, M-4) on far-infrared drying kinetics of lotus seeds, and on the variation of structure, gelation and digestive properties of lotus seed starch (LSS) before and after drying. As the maturity increased, the drying time reduced from 5.8 to 1.0 h. The reduction of drying time was correlated with the decrease of initial moisture content, the increase of water freedom and the destruction of tissue structure during ripening. The increased maturity and drying process altered the multiscale structure of LSS, including an increase in amylose content, disruption of the short-range structure, and a decrease in relative crystallinity and molecular weight. The viscosity, pasting temperature and enthalpy of LSS decreased during ripening, and drying treatment caused the further decrease. The digestibility of LSS increased during ripening and drying. Lotus seeds at M-4 would be optimal for obtaining shorter drying time, lower pasting temperature and enthalpy, and higher digestibility. This study provided theoretical guidance for achieving effective drying process and screening LSS with suitable processing properties through maturity sorting.


Assuntos
Lotus , Sementes , Amido , Sementes/química , Lotus/química , Amido/química , Dessecação/métodos , Viscosidade , Amilose/química , Peso Molecular , Digestão , Géis/química , Água/química , Temperatura , Estrutura Molecular
9.
Anal Chem ; 96(37): 14715-14719, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39229957

RESUMO

Polymer conjugation has risen in importance over the past three decades as a means of increasing the in vivo half-life of biotherapeutics, with benefits including better stability, greater drug efficacy, and lower toxicity. However, the intrinsic variability of polymer synthesis results in products with broad distributions in chain length and branching structure, complicating quality control for successful functionalization and downstream conjugation. Frequently, a combination of several analytical techniques is required for comprehensive characterization. While liquid chromatography-mass spectrometry (LC-MS) is a powerful platform that can provide detailed molecular features of polymers, the mass spectra are inherently challenging to interpret due to high mass polydispersity and overlapping charge distributions. Here, by leveraging Fourier transform-based deconvolution and macromolecular mass defect analysis, we demonstrate a new way to streamline pharmaceutical polymer analysis, shedding light on polymer size, composition, branching, and end-group functionalization with the capability for reaction monitoring.


Assuntos
Análise de Fourier , Espectrometria de Massas , Polímeros , Polímeros/química , Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , Substâncias Macromoleculares/química , Peso Molecular , Espectrometria de Massa com Cromatografia Líquida
10.
Int J Mol Sci ; 25(17)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39273248

RESUMO

Collagen is considered to be an intercellular adhesive that prevents tissue stretching or damage. It is widely utilized in cosmetic skin solutions, drug delivery, vitreous substitutions, 3D cell cultures, and surgery. In this study, we report the development of a green technology for manufacturing collagen peptides from flatfish skin using ultrasound and enzymatic treatment and a subsequent assessment on skin functionality. First, flatfish skin was extracted using ultrasound in distilled water (DW) for 6 h at 80 °C. Molecular weight analysis via high-performance liquid chromatography (HPLC) after treatment with industrial enzymes (alcalase, papain, protamex, and flavourzyme) showed that the smallest molecular weight (3.56 kDa) was achieved by adding papain (0.5% for 2 h). To determine functionality based on peptide molecular weight, two fractions of 1100 Da and 468 Da were obtained through separation using Sephadex™ G-10. We evaluated the effects of these peptides on protection against oxidative stress in human keratinocytes (HaCaT) cells, inhibition of MMP-1 expression in human dermal fibroblast (HDF) cells, reduction in melanin content, and the inhibition of tyrosinase enzyme activity in murine melanoma (B16F10) cells. These results demonstrate that the isolated low-molecular-weight peptides exhibit superior skin anti-oxidant, anti-wrinkle, and whitening properties.


Assuntos
Colágeno , Peptídeos , Pele , Animais , Humanos , Pele/efeitos dos fármacos , Pele/metabolismo , Colágeno/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Camundongos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Ondas Ultrassônicas , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Células HaCaT , Peso Molecular , Melaninas , Monofenol Mono-Oxigenase/metabolismo
11.
Int J Mol Sci ; 25(17)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39273488

RESUMO

Low-molecular-weight organic acids (LMWOAs) are essential O-containing metal-binding ligands involved in maintaining metal homeostasis, various metabolic processes, and plant responses to biotic and abiotic stress. Malate, citrate, and oxalate play a crucial role in metal detoxification and transport throughout the plant. This review provides a comparative analysis of the accumulation of LMWOAs in excluders, which store metals mainly in roots, and hyperaccumulators, which accumulate metals mainly in shoots. Modern concepts of the mechanisms of LMWOA secretion by the roots of excluders and hyperaccumulators are summarized, and the formation of various metal complexes with LMWOAs in the vacuole and conducting tissues, playing an important role in the mechanisms of metal detoxification and transport, is discussed. Molecular mechanisms of transport of LMWOAs and their complexes with metals across cell membranes are reviewed. It is discussed whether different endogenous levels of LMWOAs in plants determine their metal tolerance. While playing an important role in maintaining metal homeostasis, LMWOAs apparently make a minor contribution to the mechanisms of metal hyperaccumulation, which is associated mainly with root exudates increasing metal bioavailability and enhanced xylem loading of LMWOAs. The studies of metal-binding compounds may also contribute to the development of approaches used in biofortification, phytoremediation, and phytomining.


Assuntos
Homeostase , Metais , Plantas , Plantas/metabolismo , Metais/metabolismo , Raízes de Plantas/metabolismo , Peso Molecular , Transporte Biológico , Biodegradação Ambiental
12.
Molecules ; 29(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39274830

RESUMO

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts' biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant.


Assuntos
Antioxidantes , Cymbopogon , Flavonoides , Extratos Vegetais , Antioxidantes/farmacologia , Antioxidantes/química , Cymbopogon/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/análise , Marrocos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Peso Molecular , Espectrometria de Massas em Tandem , Polifenóis/química , Polifenóis/farmacologia , Fenóis/química , Fenóis/farmacologia , Fenóis/análise , Testes de Sensibilidade Microbiana , Cromatografia Líquida
13.
Molecules ; 29(17)2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39274983

RESUMO

This study investigated the structural composition and antioxidant properties of pectic polysaccharides extracted from Rohdea japonica (Thunb.) Roth. Pectins, which belong to a complex category of acidic polysaccharides, possess a wide range of biological effects stemming from their distinctive structural domains. The polysaccharides were extracted using water, and were subsequently purified through ion exchange and gel permeation chromatography. In order to elucidate their structural features, Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance techniques were applied. Two specific polysaccharides, WRJP-A2a and WRJP-A3b, with molecular weights of 42.7 kDa and 64.1 kDa, respectively, were identified to contain varying proportions of homogalacturonan, rhamnogalacturonan I, and rhamnogalacturonan II domains. Regarding antioxidant capacity, WRJP-A3b exhibited superior scavenging capabilities against DPPH, ABTS, and hydroxyl radicals, potentially attributed to its higher galacturonic acid content and abundance of homogalacturonan domains. These results enhance our comprehension of the structure-activity interplay of pectic polysaccharides sourced from Rohdea japonica (Thunb.) Roth and their potential utility in the healthcare and functional food sectors.


Assuntos
Antioxidantes , Pectinas , Polissacarídeos , Pectinas/química , Pectinas/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Espectroscopia de Ressonância Magnética , Picratos/química , Picratos/antagonistas & inibidores , Ácidos Hexurônicos
14.
Bioresour Technol ; 412: 131400, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39218363

RESUMO

Dynamic transformation of dissolved organic matter (DOM) contributes to short-chain fatty acids (SCFAs) production during anaerobic digestion. However, the impact of refined transformation of DOM ranked by molecular weight (MW) on SCFAs has never been investigated. Results indicated that DOM conversion order was 3500-7000 Da>(MW>14000 Da) > 7000-4000 Da during hydrolysis stage, while it was independent of their MW in acidogenesis phase and followed a low to high MW order during methanogenesis stage. Proteins-like DOMs with different MW were closely related to SCFAs. Eight groups of microorganisms (e.g., Bacillus and Caldicoprobacter) responsible for the conversion of proteins-like DOMs to SCFAs. The possible routes linking environmental properties to microorganisms-proteins-like DOMs-SCFAs connections were constructed. Microbial activity modifications by regulating moisture, pH, NO3--N and NH4+-N can expedite the conversion of proteins-like DOMs to SCFAs. The study emphasizes the importance of MW-classification-based biotransformation of organic waste, offering a potential strategy to enhance anaerobic digestion performance.


Assuntos
Ácidos Graxos Voláteis , Peso Molecular , Ácidos Graxos Voláteis/metabolismo , Anaerobiose , Compostos Orgânicos/metabolismo , Bactérias/metabolismo , Biotransformação , Hidrólise , Reatores Biológicos
15.
Int J Biol Macromol ; 278(Pt 4): 135195, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39256121

RESUMO

Based on the principle of cascade reaction, a fusion enzyme of dextransucrase and dextranase was designed without linker to catalyze the production of oligo-dextran with homogeneous molecular weight from sucrose in one catalytic step. Due to the different effects of temperature on the two components of the fusion enzyme, temperature served as the "toggle switch" for the catalytic efficiency of the two-level fusion enzyme, regulating the catalytic products of the fusion enzyme. Under optimal conditions, the fusion enzyme efficiently utilized 100 % of the sucrose, and the yield of oligo-dextran with a homogeneous molecular weight reached 70 %. The product has been purified and characterized. The probiotic potential of the product was evaluated by analyzing the growth of 10 probiotic species. Its cytotoxic and anti-inflammatory activities were also determined. The results showed that the long-chain oligo-dextran in this study had significantly better probiotic potential and anti-inflammatory activity compared to other oligosaccharides. This study provides a strategy for the application of oligo-dextran in the food and pharmaceutical industries.


Assuntos
Dextranase , Dextranos , Glucosiltransferases , Temperatura , Dextranos/química , Dextranase/metabolismo , Dextranase/química , Dextranase/genética , Glucosiltransferases/metabolismo , Glucosiltransferases/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Probióticos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Animais , Sacarose/química , Sacarose/metabolismo , Peso Molecular
16.
Int J Mol Sci ; 25(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39273101

RESUMO

Bacteriocins are a class of proteins produced by bacteria that are toxic to other bacteria. These bacteriocins play a role in bacterial competition by helping to inhibit potential competitors. In this study, we isolated and purified a novel bacteriocin Pkmh, different from the previously reported bacteriocin PA166, from Pseudomonas sp. strain 166 by ammonium sulfate precipitation, dialysis membrane method, ion exchange chromatography, and gel filtration chromatography. SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) revealed that the molecular weight of Pkmh is approximately 35 kDa. Pkmh exhibited potent antimicrobial activity against bovine Mannheimia haemolytica (M. haemolytica) with low cytotoxicity, and lower hemolytic activity was observed. In addition, Pkmh retained antimicrobial activity at different pH ranges (2-10) and temperature conditions (40, 60, 80, 100 °C). Our analysis of its antimicrobial mechanism showed that Pkmh acts on bacterial cell membranes, increasing their permeability and leading to cell membrane rupture and death. In conclusion, Pkmh exhibited low hemolytic activity, low toxicity, and potent antibacterial effects, suggesting its potential as a promising candidate for clinical therapeutic drugs.


Assuntos
Antibacterianos , Bacteriocinas , Bacteriocinas/farmacologia , Bacteriocinas/química , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Hemólise/efeitos dos fármacos , Mannheimia haemolytica/efeitos dos fármacos , Pseudomonas/efeitos dos fármacos , Bovinos , Testes de Sensibilidade Microbiana , Humanos , Peso Molecular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Temperatura , Concentração de Íons de Hidrogênio
17.
Sci Rep ; 14(1): 20564, 2024 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232139

RESUMO

High molecular weight polyethylenimine (HMW PEI; branched 25 kDa PEI) has been widely investigated for gene delivery due to its high transfection efficiency. However, the toxicity and lack of targeting to specific cells have limited its clinical application. In the present investigation, L-3, 4-dihydroxyphenylalanine (L-DOPA) was conjugated on HMW PEI in order to target L-type amino acid transporter 1 (LAT-1) and modulate positive charge density on the surface of polymer/plasmid complexes (polyplexes). The results of biophysical characterization revealed that the PEI conjugates are able to form nanoparticles ≤ 180 nm with the zeta potential ranging from + 9.5-12.4 mV. These polyplexes could condense plasmid DNA and protect it against nuclease digestion at the carrier to plasmid ratios higher than 4. L-DOPA conjugated PEI derivatives were complexed with a plasmid encoding human interleukin-12 (hIL-12). Targeted polyplexes showed up to 2.5 fold higher transfection efficiency in 4T1 murine mammary cancer cell line, which expresses LAT-1, than 25 kDa PEI polyplexes prepared in the same manner. The cytotoxicity of these polyplexes was also substantially lower than the unmodified parent HMW PEI. These results support the use of L-3, 4-dihydroxyphenylalanine derivatives of PEI in any attempt to develop a LAT-1 targeted gene carrier.


Assuntos
Peso Molecular , Plasmídeos , Polietilenoimina , Polietilenoimina/química , Plasmídeos/genética , Plasmídeos/química , Animais , Camundongos , Linhagem Celular Tumoral , Humanos , Di-Hidroxifenilalanina/química , Transfecção/métodos , Técnicas de Transferência de Genes , Interleucina-12/metabolismo , Interleucina-12/genética , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/genética , Nanopartículas/química , DNA/química
18.
Arch Microbiol ; 206(9): 377, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141120

RESUMO

The high content and quality of protein in Andean legumes make them valuable for producing protein hydrolysates using proteases from bacteria isolated from extreme environments. This study aimed to carry out a single-step purification of a haloprotease from Micrococcus sp. PC7 isolated from Peru salterns. In addition, characterize and apply the enzyme for the production of bioactive protein hydrolysates from underutilized Andean legumes. The PC7 protease was fully purified using only tangential flow filtration (TFF) and exhibited maximum activity at pH 7.5 and 40 °C. It was characterized as a serine protease with an estimated molecular weight of 130 kDa. PC7 activity was enhanced by Cu2+ (1.7-fold) and remained active in the presence of most surfactants and acetonitrile. Furthermore, it stayed completely active up to 6% NaCl and kept Ì´ 60% of its activity up to 8%. The protease maintained over 50% of its activity at 25 °C and 40 °C and over 70% at pH from 6 to 10 for up to 24 h. The determined Km and Vmax were 0.1098 mg mL-1 and 273.7 U mL-1, respectively. PC7 protease hydrolyzed 43%, 22% and 11% of the Lupinus mutabilis, Phaseolus lunatus and Erythrina edulis protein concentrates, respectively. Likewise, the hydrolysates from Lupinus mutabilis and Erythrina edulis presented the maximum antioxidant and antihypertensive activities, respectively. Our results demonstrated the feasibility of a simple purification step for the PC7 protease and its potential to be applied in industrial and biotechnological processes. Bioactive protein hydrolysates produced from Andean legumes may lead to the development of nutraceuticals and functional foods contributing to address some United Nations Sustainable Development Goals (SDGs).


Assuntos
Fabaceae , Micrococcus , Hidrolisados de Proteína , Micrococcus/metabolismo , Micrococcus/enzimologia , Concentração de Íons de Hidrogênio , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Peso Molecular , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/isolamento & purificação , Peru , Temperatura , Serina Proteases/metabolismo , Serina Proteases/isolamento & purificação , Serina Proteases/química , Estabilidade Enzimática , Cloreto de Sódio/metabolismo , Cloreto de Sódio/farmacologia , Hidrólise , Cinética
19.
J Am Soc Mass Spectrom ; 35(9): 2041-2055, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39140654

RESUMO

In this investigation, we detail the synthesis of silver nanoparticles (AgNPs) via a precise chemical vacuum deposition (CVD) methodology, aimed at augmenting the analytical performance of laser desorption/ionization mass spectrometry (LDI-MS) for the detection of low-molecular-weight analytes. Employing a precursor supply rate of 0.0014 mg/s facilitated the formation of uniformly dispersed AgNPs, characterized by SEM and AFM to have an average diameter of 33.5 ± 1.5 nm and a surface roughness (Ra) of 11.8 nm, indicative of their homogeneous coverage and spherical morphology. XPS and SEM-EDX analyses confirmed the metallic silver composition of the nanoparticles with Ag peak splitting, reflecting the successful synthesis of metallic Ag. Comparative analytical evaluation with traditional MALDI matrices revealed that AgNPs significantly reduce signal suppression, thereby enhancing the sensitivity and specificity of LDI-MS for low-molecular-weight compounds such as triglycerides, saccharides, amino acids, and carboxylic acids. Notably, the application of AgNPs demonstrated a superior linear response for triglyceride signals with regression coefficients surpassing 0.99, markedly outperforming conventional matrices. The study further extends into quantitative analysis through nanoparticle-based laser desorption/ionization (NALDI), where AgNPs exhibited enhanced ionization efficiency, characterized by substantially lower limits of detection (LOD) and quantification (LOQ) for tested standards. Particular attention was paid to lipids with a detailed examination of their fragmentation pathways. These results highlight the significant potential of AgNPs synthesized via CVD to transform the analytical detection and quantification of low-molecular-weight compounds using NALDI. This approach offers a promising avenue for expanding the scope of analytical applications in mass spectrometry and introducing innovative methodologies for enhanced precision and sensitivity.


Assuntos
Nanopartículas Metálicas , Prata , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Prata/química , Nanopartículas Metálicas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Aminoácidos/análise , Aminoácidos/química , Peso Molecular , Triglicerídeos/análise , Triglicerídeos/química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/análise , Limite de Detecção
20.
Int J Biol Macromol ; 277(Pt 3): 134425, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39097065

RESUMO

In this study, deep eutectic solvent (DES) prepared from choline chloride, lactic acid, and one of the four polyols (ethylene glycol, glycerol, xylitol, and sorbitol) were compared and assessed for their effectiveness in extracting chitin from lobster shells. Our results revealed that as the number of hydroxyl groups in polyols increased, the hydrogen bond network within the DESs became denser. However, this led to a corresponding increase in viscosity, which impacted the efficiency of chitin extraction. Among all prepared DESs, choline chloride-lactic acid/glycerol (CCLaGly) exhibited superior extractive ability, resulting in the extraction of pure chitin from lobster shells. The purity, crystallinity, and molecular weight of the extracted chitin using CCLaGly DES were comparable to those of chemically-isolated chitin, with purity reaching 94.76 ± 0.33 %, crystallinity at 78.78 %, and a molecular weight of 655 kDa. Additionally, the physicochemical properties of the DES-extracted chitins were characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. This study conducted a comparative analysis of polyol effects on chitin extraction from lobster shells, thereby opening a promising avenue for the utilization of various crustacean shells in sustainable biomaterial production.


Assuntos
Exoesqueleto , Quitina , Solventes Eutéticos Profundos , Polímeros , Quitina/química , Quitina/isolamento & purificação , Animais , Polímeros/química , Exoesqueleto/química , Solventes Eutéticos Profundos/química , Viscosidade , Peso Molecular , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Nephropidae/química
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