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1.
Carbohydr Polym ; 340: 122316, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38858029

RESUMO

Epimedium, a traditional Chinese medicine commonly used as a dietary supplement, contains polysaccharides and flavonoids as its main bioactive ingredients. In this study, a neutral homogeneous polysaccharide (EPSN-1) was isolated from Epimedium brevicornu Maxim. EPSN-1 was identified as a glucan with a backbone of →4)-α-D-Glcp-(1→, branched units comprised α-D-Glcp-(1→6)-α-D-Glcp-(1→, ß-D-Glcp-(1→6)-ß-D-Glcp-(1→ and α-D-Glcp-(1→ connected to the C6 position of backbone. The conformation of EPSN-1 in aqueous solution indicated its potential to form nanoparticles. This paper aims to investigate the carrier and pharmacodynamic activity of EPSN-1. The findings demonstrated that, on the one hand, EPSN-1, as a functional ingredient, may load Icariin (ICA) through non-covalent interactions, improving its biopharmaceutical properties such as solubility and stability, thereby improving its intestinal absorption. Additionally, as an effective ingredient, EPSN-1 could help maintain the balance of the intestinal environment by increasing the abundance of Parabacteroides, Lachnospiraceae UGG-001, Anaeroplasma, and Eubacterium xylanophilum group, while decreasing the abundance of Allobaculum, Blautia, and Adlercreutzia. Overall, this dual action of EPSN-1 sheds light on the potential applications of natural polysaccharides, highlighting their dual role as carriers and contributors to biological activity.


Assuntos
Epimedium , Flavonoides , Glucanos , Hiperplasia Prostática , Epimedium/química , Masculino , Glucanos/química , Glucanos/farmacologia , Glucanos/isolamento & purificação , Hiperplasia Prostática/tratamento farmacológico , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Animais , Portadores de Fármacos/química , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos
2.
Carbohydr Polym ; 339: 122214, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823900

RESUMO

The polysaccharide, RGP2, was isolated from Russula griseocarnosa and its immunostimulatory effects were confirmed in cyclophosphamide (CTX)-induced immunosuppressed mice. Following purification via chromatography, structural analysis revealed that RGP2 had a molecular weight of 11.82 kDa and consisted of glucose (Glc), galactose (Gal), mannose, glucuronic acid and glucosamine. Bond structure analysis and nuclear magnetic resonance characterization confirmed that the main chain of RGP2 was formed by →6)-ß-D-Glcp-(1→, →3)-ß-D-Glcp-(1→ and →6)-α-D-Galp-(1→, which was substituted at O-3 of →6)-ß-D-Glcp-(1→ by ß-D-Glcp-(1→. RGP2 was found to ameliorate pathological damage in the spleen and enhance immune cell activity in immunosuppressed mice. Based on combined multiomics analysis, RGP2 altered the abundance of immune-related microbiota (such as Lactobacillus, Faecalibacterium, and Bacteroides) in the gut and metabolites (uridine, leucine, and tryptophan) in the serum. Compared with immunosuppressed mice, RGP2 also restored the function of antigen-presenting cells, promoted the polarization of macrophages into the M1 phenotype, positively affected the differentiation of helper T cells, and inhibited regulatory T cell differentiation through the protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) pathway, ultimately exerting an immune boosting function. Overall, our findings highlight therapeutic strategies to alleviate CTX-induced immunosuppression in a clinical setting.


Assuntos
Basidiomycota , Diferenciação Celular , Glucanos , Animais , Camundongos , Basidiomycota/química , Glucanos/química , Glucanos/farmacologia , Glucanos/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/química , Masculino , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Ciclofosfamida/farmacologia , Camundongos Endogâmicos BALB C , Microbioma Gastrointestinal/efeitos dos fármacos
3.
Int J Biol Macromol ; 272(Pt 1): 132845, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38830495

RESUMO

Brown seaweed-derived polysaccharides, notably fucoidan and laminarin, are known for their extensive array of bioactivities and physicochemical properties. However, the effects of upper digestive tract modification on the bioactive performance of fucoidan and laminarin fractions (FLFs) sourced from Australian native species are largely unknown. Here, the digestibility and bioaccessibility of FLFs were evaluated by tracking the dynamic changes in reducing sugar content (CR), profiling the free monosaccharide composition using LC-MS, and comparing high-performance gel permeation chromatography profile variation via LC-SEC-RI. The effects of digestive progression on bioactive performance were assessed by comparing the antioxidant and antidiabetic potential of FLFs and FLF digesta. We observed that molecular weight (Mw) decreased during gastric digestion indicating that FLF aggregates were disrupted in the stomach. During intestinal digestion, Mw gradually decreased and CR increased indicating cleavage of glycosidic bonds releasing free sugars. Although the antioxidant and antidiabetic capacities were not eliminated by the digestion progression, the bioactive performance of FLFs under a digestive environment was reduced contrasting with the same concentration level of the undigested FLFs. These data provide comprehensive information on the digestibility and bioaccessibility of FLFs, and shed light on the effects of digestive progression on bioactive expression.


Assuntos
Antioxidantes , Polissacarídeos , Alga Marinha , Polissacarídeos/química , Polissacarídeos/farmacologia , Alga Marinha/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Trato Gastrointestinal Superior/metabolismo , Trato Gastrointestinal Superior/efeitos dos fármacos , Peso Molecular , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Digestão/efeitos dos fármacos , Sulfatos/química , Glucanos/química , Glucanos/farmacologia , Phaeophyceae/química , Humanos
4.
Int J Biol Macromol ; 272(Pt 1): 132834, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838885

RESUMO

The development of novel packaging materials with antimicrobial properties is crucial in preventing the microbial-induced spoilage of fruits, vegetables, and foodborne illnesses. In this study, homojunction g-C3N4 (HCN) photocatalysts with excellent photocatalytic performance were incorporated into a matrix consisting of pullulan/chitosan (Pul/CS). These photocatalysts were then electrostatically spun onto polylactic acid (PLA) films to fabricate PLA@Pul/CS/HCN nanofibrous composite films. The design of the bilayer films aimed to combine the physical properties of PLA film with the excellent antibacterial properties of nanofiber films, thereby achieving synergistic advantages. The incorporation of the HCN photocatalysts resulted in enhanced hydrophobicity, barrier function, and mechanical properties of the composite films. Under visible light irradiation, the PLA@Pul/CS/HCN films exhibited approximately 3.43 log and 3.11 log reductions of Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA), respectively, within 2 h. The excellent antimicrobial performance could be attributed to the synergistic effect of CS and the release of reactive oxygen species (ROS) from HCN. Moreover, the strawberries packaged in the PLA@Pul/CS/HCN film demonstrated diminished quality degradation and a prolonged shelf life following visible light irradiation treatment. This study will provide new insights into the exploration of safe and efficient antimicrobial food packaging.


Assuntos
Quitosana , Embalagem de Alimentos , Frutas , Glucanos , Luz , Poliésteres , Glucanos/química , Glucanos/farmacologia , Poliésteres/química , Quitosana/química , Quitosana/farmacologia , Frutas/química , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fragaria/microbiologia , Nanofibras/química , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Grafite , Compostos de Nitrogênio
5.
Carbohydr Polym ; 337: 122171, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710561

RESUMO

Commercially available mushroom polysaccharides have found widespread use as adjuvant tumor treatments. However, the bioactivity of polysaccharides in Lactarius hatsudake Tanaka (L. hatsudake), a mushroom with both edible and medicinal uses, remains relatively unexplored. To address this gap, five L. hatsudake polysaccharides with varying molecular weights were isolated, named LHP-1 (898 kDa), LHP-2 (677 kDa), LHP-3 (385 kDa), LHP-4 (20 kDa), and LHP-5 (4.9 kDa). Gas chromatography-mass spectrometry, nuclear magnetic resonance, and atomic force microscopy, etc., were employed to determine their structural characteristics. The results confirmed that spherical aggregates with amorphous flexible fiber chains dominated the conformation of the LHP. LHP-1 and LHP-2 were identified as glucans with α-(1,4)-Glcp as the main chain; LHP-3 and LHP-4 were classified as galactans with varying molecular weights but with α-(1,6)-Galp as the main chain; LHP-5 was a glucan with ß-(1,3)-Glcp as the main chain and ß-(1,6)-Glcp connecting to the side chains. Significant differences were observed in inhibiting tumor cell cytotoxicity and the antioxidant activity of the LHPs, with LHP-5 and LHP-4 identified as the principal bioactive components. These findings provide a theoretical foundation for the valuable use of L. hatsudake and emphasize the potential application of LHPs in therapeutic tumor treatments.


Assuntos
Antioxidantes , Glucanos , Glucanos/química , Glucanos/farmacologia , Glucanos/isolamento & purificação , Humanos , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Agaricales/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Peso Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/isolamento & purificação , Basidiomycota/química , Sobrevivência Celular/efeitos dos fármacos
6.
Carbohydr Polym ; 337: 122149, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710571

RESUMO

Phytopathogen cell wall polysaccharides have important physiological functions. In this study, we isolated and characterized the alkali-insoluble residue on the inner layers of the Rhizoctonia solani AG1 IA cell wall (RsCW-AIR). Through chemical composition and structural analysis, RsCW-AIR was mainly identified as a complex of chitin/chitosan and glucan (ChCsGC), with glucose and glucosamine were present in a molar ratio of 2.7:1.0. The predominant glycosidic bond linkage of glucan in ChCsGC was ß-1,3-linked Glcp, both the α and ß-polymorphic forms of chitin were presented in it by IR, XRD, and solid-state NMR, and the ChCsGC exhibited a degree of deacetylation measuring 67.08 %. RsCW-AIR pretreatment effectively reduced the incidence of rice sheath blight, and its induced resistance activity in rice was evaluated, such as inducing a reactive oxygen species (ROS) burst, leading to the accumulation of salicylic acid (SA) and the up-regulation of SA-related gene expression. The recognition of RsCW-AIR in rice is partially dependent on CERK1.


Assuntos
Parede Celular , Quitina , Quitosana , Glucanos , Oryza , Doenças das Plantas , Rhizoctonia , Rhizoctonia/efeitos dos fármacos , Oryza/microbiologia , Oryza/química , Parede Celular/química , Quitosana/química , Quitosana/farmacologia , Quitina/química , Quitina/farmacologia , Glucanos/química , Glucanos/farmacologia , Doenças das Plantas/microbiologia , Resistência à Doença , Espécies Reativas de Oxigênio/metabolismo
7.
World J Gastroenterol ; 30(16): 2258-2271, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38690023

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is one of the most frequent and debilitating conditions leading to gastroenterological referrals. However, recommended treatments remain limited, yielding only limited therapeutic gains. Chitin-glucan (CG) is a novel dietary prebiotic classically used in humans at a dosage of 1.5-3.0 g/d and is considered a safe food ingredient by the European Food Safety Authority. To provide an alternative approach to managing patients with IBS, we performed preclinical molecular, cellular, and animal studies to evaluate the role of chitin-glucan in the main pathophysiological mechanisms involved in IBS. AIM: To evaluate the roles of CG in visceral analgesia, intestinal inflammation, barrier function, and to develop computational molecular models. METHODS: Visceral pain was recorded through colorectal distension (CRD) in a model of long-lasting colon hypersensitivity induced by an intra-rectal administration of TNBS [15 milligrams (mg)/kilogram (kg)] in 33 Sprague-Dawley rats. Intracolonic pressure was regularly assessed during the 9 wk-experiment (weeks 0, 3, 5, and 7) in animals receiving CG (n = 14) at a human equivalent dose (HED) of 1.5 g/d or 3.0 g/d and compared to negative control (tap water, n = 11) and positive control (phloroglucinol at 1.5 g/d HED, n = 8) groups. The anti-inflammatory effect of CG was evaluated using clinical and histological scores in 30 C57bl6 male mice with colitis induced by dextran sodium sulfate (DSS) administered in their drinking water during 14 d. HT-29 cells under basal conditions and after stimulation with lipopolysaccharide (LPS) were treated with CG to evaluate changes in pathways related to analgesia (µ-opioid receptor (MOR), cannabinoid receptor 2 (CB2), peroxisome proliferator-activated receptor alpha, inflammation [interleukin (IL)-10, IL-1b, and IL-8] and barrier function [mucin 2-5AC, claudin-2, zonula occludens (ZO)-1, ZO-2] using the real-time PCR method. Molecular modelling of CG, LPS, lipoteichoic acid (LTA), and phospholipomannan (PLM) was developed, and the ability of CG to chelate microbial pathogenic lipids was evaluated by docking and molecular dynamics simulations. Data were expressed as the mean ± SEM. RESULTS: Daily CG orally-administered to rats or mice was well tolerated without including diarrhea, visceral hypersensitivity, or inflammation, as evaluated at histological and molecular levels. In a model of CRD, CG at a dosage of 3 g/d HED significantly decreased visceral pain perception by 14% after 2 wk of administration (P < 0.01) and reduced inflammation intensity by 50%, resulting in complete regeneration of the colonic mucosa in mice with DSS-induced colitis. To better reproduce the characteristics of visceral pain in patients with IBS, we then measured the therapeutic impact of CG in rats with TNBS-induced inflammation to long-lasting visceral hypersensitivity. CG at a dosage of 1.5 g/d HED decreased visceral pain perception by 20% five weeks after colitis induction (P < 0.01). When the CG dosage was increased to 3.0 g/d HED, this analgesic effect surpassed that of the spasmolytic agent phloroglucinol, manifesting more rapidly within 3 wk and leading to a 50% inhibition of pain perception (P < 0.0001). The underlying molecular mechanisms contributing to these analgesic and anti-inflammatory effects of CG involved, at least in part, a significant induction of MOR, CB2 receptor, and IL-10, as well as a significant decrease in pro-inflammatory cytokines IL-1b and IL-8. CG also significantly upregulated barrier-related genes including muc5AC, claudin-2, and ZO-2. Molecular modelling of CG revealed a new property of the molecule as a chelator of microbial pathogenic lipids, sequestering gram-negative LPS and gram-positive LTA bacterial toxins, as well as PLM in fungi at the lowesr energy conformations. CONCLUSION: CG decreased visceral perception and intestinal inflammation through master gene regulation and direct binding of microbial products, suggesting that CG may constitute a new therapeutic strategy for patients with IBS or IBS-like symptoms.


Assuntos
Quitina , Colo , Modelos Animais de Doenças , Glucanos , Síndrome do Intestino Irritável , Ratos Sprague-Dawley , Dor Visceral , Animais , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/fisiopatologia , Masculino , Humanos , Colo/efeitos dos fármacos , Colo/patologia , Ratos , Dor Visceral/tratamento farmacológico , Dor Visceral/fisiopatologia , Dor Visceral/metabolismo , Dor Visceral/etiologia , Quitina/farmacologia , Glucanos/farmacologia , Glucanos/administração & dosagem , Camundongos , Prebióticos/administração & dosagem , Ácido Trinitrobenzenossulfônico/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite/fisiopatologia , Colite/patologia , Células HT29
8.
Int J Biol Macromol ; 269(Pt 1): 132109, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38714281

RESUMO

This study presents a novel and efficient approach for pullulan production using artificial neural networks (ANNs) to optimize semi-solid-state fermentation (S-SSF) on faba bean biomass (FBB). This method achieved a record-breaking pullulan yield of 36.81 mg/g within 10.82 days, significantly exceeding previous results. Furthermore, the study goes beyond yield optimization by characterizing the purified pullulan, revealing its unique properties including thermal stability, amorphous structure, and antioxidant activity. Energy-dispersive X-ray spectroscopy and scanning electron microscopy confirmed its chemical composition and distinct morphology. This research introduces a groundbreaking combination of ANNs and comprehensive characterization, paving the way for sustainable and cost-effective pullulan production on FBB under S-SSF conditions. Additionally, the study demonstrates the successful integration of pullulan with Ag@TiO2 nanoparticles during synthesis using Fusarium oxysporum. This novel approach significantly enhances the stability and efficacy of the nanoparticles by modifying their surface properties, leading to remarkably improved antibacterial activity against various human pathogens. These findings showcase the low-cost production medium, and extensive potential of pullulan not only for its intrinsic properties but also for its ability to significantly improve the performance of nanomaterials. This breakthrough opens doors to diverse applications in various fields.


Assuntos
Antibacterianos , Aureobasidium , Fermentação , Glucanos , Nanocompostos , Redes Neurais de Computação , Prata , Titânio , Glucanos/química , Glucanos/biossíntese , Glucanos/farmacologia , Nanocompostos/química , Titânio/química , Titânio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Aureobasidium/metabolismo , Prata/química , Prata/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Fusarium
9.
PLoS One ; 19(5): e0304833, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820480

RESUMO

Considering the differences in molecular structure and function, the effects of ß-1,3-glucans from Euglena gracilis and ß-1,3/1,6-glucans from Saccharomyces cerevisiae on immune and inflammatory activities in dogs were compared. Four diets were compared: control without ß-glucans (CON), 0.15 mg/kg BW/day of ß-1,3/1,6-glucans (Β-Y15), 0.15 mg/kg BW/day of ß-1,3-glucans (Β-S15), and 0.30 mg/kg BW/day of ß-1,3-glucans (Β-S30). Thirty-two healthy dogs (eight per diet) were organized in a block design. All animals were fed CON for a 42-day washout period and then sorted into one of four diets for 42 days. Blood and faeces were collected at the beginning and end of the food intake period and analysed for serum and faecal cytokines, ex vivo production of hydrogen peroxide (H2O2) and nitric oxide (NO), phagocytic activity of neutrophils and monocytes, C-reactive protein (CRP), ex vivo production of IgG, and faecal concentrations of IgA and calprotectin. Data were evaluated using analysis of covariance and compared using Tukey's test (P<0.05). Dogs fed Β-Y15 showed higher serum IL-2 than dogs fed Β-S30 (P<0.05). A higher phagocytic index of monocytes was observed in dogs fed the B-S15 diet than in those fed the other diets, and a higher neutrophil phagocytic index was observed for B-S15 and B-Y15 than in dogs fed the CON diet (P<0.05). Monocytes from dogs fed B-S15 and B-S30 produced more NO and less H2O2 than those from the CON and B-Y15 groups (P<0.05). Despite in the reference value, CRP levels were higher in dogs fed B-S15 and B-S30 diets (P<0.05). ß-1,3/1,6-glucan showed cell-mediated activation of the immune system, with increased serum IL-2 and neutrophil phagocytic index, whereas ß-1,3-glucan acted on the immune system by increasing the ex vivo production of NO by monocytes, neutrophil phagocytic index, and serum CRP. Calprotectin and CRP levels did not support inflammation or other health issues related to ß-glucan intake. In conclusion, both ß-glucan sources modulated some immune and inflammatory parameters in dogs, however, different pathways have been suggested for the recognition and action of these molecules, reinforcing the necessity for further mechanistic studies, especially for E. gracilis ß-1,3-glucan.


Assuntos
Euglena gracilis , Fezes , Saccharomyces cerevisiae , beta-Glucanas , Animais , Cães , beta-Glucanas/farmacologia , Fezes/química , Inflamação , Masculino , Óxido Nítrico/metabolismo , Citocinas/metabolismo , Proteína C-Reativa/metabolismo , Proteína C-Reativa/análise , Peróxido de Hidrogênio/metabolismo , Fagocitose/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Feminino , Imunoglobulina G/sangue , Glucanos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo
10.
PLoS One ; 19(5): e0294998, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38713688

RESUMO

Tularemia is a zoonotic disease caused by the facultative intracellular gram-negative bacterium Francisella tularensis. F. tularensis has a very low infection dose by the aerosol route which can result in an acute, and potentially lethal, infection in humans. Consequently, it is classified as a Category A bioterrorism agent by the US Centers for Disease Control (CDC) and is a pathogen of concern for the International Biodefence community. There are currently no licenced tularemia vaccines. In this study we report on the continued assessment of a tularemia subunit vaccine utilising ß-glucan particles (GPs) as a vaccine delivery platform for immunogenic F. tularensis antigens. Using a Fischer 344 rat infection model, we demonstrate that a GP based vaccine comprising the F. tularensis lipopolysaccharide antigen together with the protein antigen FTT0814 provided partial protection of F344 rats against an aerosol challenge with a high virulence strain of F. tularensis, SCHU S4. Inclusion of imiquimod as an adjuvant failed to enhance protective efficacy. Moreover, the level of protection afforded was dependant on the challenge dose. Immunological characterisation of this vaccine demonstrated that it induced strong antibody immunoglobulin responses to both polysaccharide and protein antigens. Furthermore, we demonstrate that the FTT0814 component of the GP vaccine primed CD4+ and CD8+ T-cells from immunised F344 rats to express interferon-γ, and CD4+ cells to express interleukin-17, in an antigen specific manner. These data demonstrate the development potential of this tularemia subunit vaccine and builds on a body of work highlighting GPs as a promising vaccine platform for difficult to treat pathogens including those of concern to the bio-defence community.


Assuntos
Vacinas Bacterianas , Modelos Animais de Doenças , Francisella tularensis , Ratos Endogâmicos F344 , Tularemia , Vacinas de Subunidades Antigênicas , Animais , Tularemia/prevenção & controle , Tularemia/imunologia , Ratos , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Francisella tularensis/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Glucanos/imunologia , Glucanos/farmacologia , Linfócitos T/imunologia , Feminino , Antígenos de Bactérias/imunologia
11.
Microbiology (Reading) ; 170(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38739436

RESUMO

Endolysins are bacteriophage (or phage)-encoded enzymes that catalyse the peptidoglycan breakdown in the bacterial cell wall. The exogenous action of recombinant phage endolysins against Gram-positive organisms has been extensively studied. However, the outer membrane acts as a physical barrier when considering the use of recombinant endolysins to combat Gram-negative bacteria. This study aimed to evaluate the antimicrobial activity of the SAR-endolysin LysKpV475 against Gram-negative bacteria as single or combined therapies, using an outer membrane permeabilizer (polymyxin B) and a phage, free or immobilized in a pullulan matrix. In the first step, the endolysin LysKpV475 in solution, alone and combined with polymyxin B, was tested in vitro and in vivo against ten Gram-negative bacteria, including highly virulent strains and multidrug-resistant isolates. In the second step, the lyophilized LysKpV475 endolysin was combined with the phage phSE-5 and investigated, free or immobilized in a pullulan matrix, against Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311. The bacteriostatic action of purified LysKpV475 varied between 8.125 µg ml-1 against Pseudomonas aeruginosa ATCC 27853, 16.25 µg ml-1 against S. enterica Typhimurium ATCC 13311, and 32.50 µg ml-1 against Klebsiella pneumoniae ATCC BAA-2146 and Enterobacter cloacae P2224. LysKpV475 showed bactericidal activity only for P. aeruginosa ATCC 27853 (32.50 µg ml-1) and P. aeruginosa P2307 (65.00 µg ml-1) at the tested concentrations. The effect of the LysKpV475 combined with polymyxin B increased against K. pneumoniae ATCC BAA-2146 [fractional inhibitory concentration index (FICI) 0.34; a value lower than 1.0 indicates an additive/combined effect] and S. enterica Typhimurium ATCC 13311 (FICI 0.93). A synergistic effect against S. enterica Typhimurium was also observed when the lyophilized LysKpV475 at ⅔ MIC was combined with the phage phSE-5 (m.o.i. of 100). The lyophilized LysKpV475 immobilized in a pullulan matrix maintained a significant Salmonella reduction of 2 logs after 6 h of treatment. These results demonstrate the potential of SAR-endolysins, alone or in combination with other treatments, in the free form or immobilized in solid matrices, which paves the way for their application in different areas, such as in biocontrol at the food processing stage, biosanitation of food contact surfaces and biopreservation of processed food in active food packing.


Assuntos
Antibacterianos , Endopeptidases , Glucanos , Polimixina B , Fagos de Salmonella , Endopeptidases/farmacologia , Endopeptidases/química , Endopeptidases/metabolismo , Polimixina B/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Fagos de Salmonella/genética , Fagos de Salmonella/fisiologia , Fagos de Salmonella/química , Glucanos/química , Glucanos/farmacologia , Animais , Testes de Sensibilidade Microbiana , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/virologia , Camundongos , Salmonella typhimurium/virologia , Salmonella typhimurium/efeitos dos fármacos , Bacteriófagos/fisiologia , Bacteriófagos/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo , Proteínas Virais/farmacologia , Proteínas Virais/química
12.
Int J Biol Macromol ; 269(Pt 2): 132068, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719001

RESUMO

Pullulan was used as the wall material for microencapsulation of L. plantarum CRD7 by spray drying, while isomalto-oligosaccharides (IMO) was used as prebiotic. Also, the effect of different thermal protectants on survival rate during microencapsulation was evaluated. Taguchi orthogonal array design showed that pullulan at 14 % concentration, IMO at 30 % concentration and whey protein isolate at 20 % rate were the optimized wall material, prebiotic and thermal protectant, respectively for microencapsulation of L. plantarum. FESEM images revealed that the spray-dried encapsulates were fibrous similar to those produce by electrospinning, while fluorescence microscopy ascertained that most of the probiotic cells were alive and intact after microencapsulation. The adsorption-desorption isotherm was of Type II and the encapsulate had specific surface area of 1.92 m2/g and mean pore diameter of 15.12 nm. The typical amide II and III bands of the bacterial proteins were absent in the FTIR spectra, suggestive of adequate encapsulation. DSC thermogram showed shifting of melting peaks to wider temperature range due to interactions between the probiotic and wall materials. IMO at 30 % (w/w) along with WPI at 20 % concentration provided the highest storage stability and the lowest rate of cell death of L. plantarum after microencapsulation. Acid and bile salt tolerance results confirmed that microencapsulated L. plantarum could sustain the harsh GI conditions with >7.5 log CFU/g viability. After microencapsulation, L. plantarum also possessed the ability to ferment milk into curd with pH of 4.62.


Assuntos
Glucanos , Lactobacillus plantarum , Prebióticos , Glucanos/química , Glucanos/farmacologia , Lactobacillus plantarum/química , Secagem por Atomização , Probióticos/química , Viabilidade Microbiana/efeitos dos fármacos , Composição de Medicamentos , Proteínas do Soro do Leite/química , Oligossacarídeos/química , Oligossacarídeos/farmacologia
13.
Int J Biol Macromol ; 268(Pt 1): 131640, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636750

RESUMO

Visceral and somatic hypersensitivity is a common cause of functional dyspepsia. Marine bioactive components have been revealed to possess numerous valuable abilities. However, as a kind of polysaccharide extracted from brown algae, the study focused on the biological properties of laminarin is still limited, especially in gastrointestinal disorders. In our study, indicators associated with visceral sensational function and gastrointestinal microecology were determined to investigate the modulatory effects of laminarin on functional dyspepsia induced by iodoacetamide. Mice with visceral hypersensitivity were orally administrated with laminarin (50 and 100 mg per kg bw) for fourteen days. The results indicated that laminarin partly alleviated the dysfunction by regulating corticosterone secretion, the expression of 5HT3 receptors at both protein and mRNA levels, and mechanical transduction through the PIEZO2-EPAC1 axis. Furthermore, laminarin administration moderated the imbalanced gut microbial profile, including modulating the abundance of Bacteroidetes and Firmicutes. Our findings revealed that laminarin may restore the overexpression of 5HT3 receptors, the abnormal mechanical transduction, and impaired gut microecology. In conclusion, we provide evidence to support the utilization of laminarin as the ingredient of complementary and alternative medicine of regulating visceral and somatic hypersensitivity.


Assuntos
Dispepsia , Microbioma Gastrointestinal , Glucanos , Iodoacetamida , Receptores 5-HT3 de Serotonina , Animais , Receptores 5-HT3 de Serotonina/metabolismo , Receptores 5-HT3 de Serotonina/genética , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Dispepsia/tratamento farmacológico , Dispepsia/metabolismo , Glucanos/farmacologia , Masculino , Iodoacetamida/farmacologia , Corticosterona/sangue
14.
Environ Res ; 252(Pt 1): 118836, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565415

RESUMO

Marine algae-based drug discovery has recently received a lot of attention. This study was conducted to extract laminarin-enriched solvent extracts from Padina tetrastromatica and Sargassum cinereum and to evaluate their anticancer activity against the HeLa cell line in vitro (MTT assay). Furthermore, their toxicity was determined through a zebra fish model study. P. tetrastromatica and S. cinereum biomasses have a higher concentration of essential biomolecules such as carbohydrates, protein, and crude fiber, as well as essential minerals (Na, Mg, K, Ca, and Fe) and secondary metabolites. Methanol extracts, in particular, contain a higher concentration of vital phytochemicals than other solvent extracts. The laminarin quantification assay states that methanol extracts of P. tetrastromatica and S. cinereum are rich in laminarin, which is primarily confirmed by FTIR analysis. In an anticancer study, laminarin-MeE from P. tetrastromatica and S. cinereum at concentrations of 750 and 1000 µg mL-1 demonstrated 100% activity against HeLa cells. The Zebra fish model-based toxicity study revealed that the laminarin-enriched MeE of P. tetrastromatica and S. cinereum is non-toxic. These findings revealed that the laminarin-enriched MeE of P. tetrastromatica and S. cinereum has significant anticancer activity without causing toxicity.


Assuntos
Glucanos , Sargassum , Peixe-Zebra , Células HeLa , Humanos , Glucanos/farmacologia , Glucanos/química , Animais , Sargassum/química , Biomassa , Antineoplásicos/farmacologia , Antineoplásicos/química
15.
Int J Biol Macromol ; 267(Pt 2): 131606, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631566

RESUMO

This study aimed to investigate the effect of cinnamon essential oil (CEO)-loaded metal-organic frameworks (CEO@MOF) on the properties of gelatin/pullulan (Gel/Pull)-based composite films (Gel/Pull-based films). The incorporation of CEO@MOF into Gel/Pull-based films demonstrated significant antimicrobial activity against S. aureus, S. enterica, E. coli, and L. monocytogenes. Additionally, CEO@MOF integrated film exhibited a 98.16 % ABTS radical scavenging, with no significant change in the mechanical properties of the neat Gel/Pull film. The UV blocking efficiency of the composite films increased significantly from 81.38 to 99.56 % at 280 nm with the addition of 3 wt% CEO@MOF. Additionally, Gel/Pull/CEO@MOF films effectively extended the shelf life of meat preserved at 4 °C by reducing moisture loss by 3.35 %, maintaining the pH within the threshold limit (6.2), and inhibiting bacterial growth by 99.9 %. These results propose that CEO@MOF has significant potential as an effective additive in active packaging to improve shelf life and food safety.


Assuntos
Cinnamomum zeylanicum , Embalagem de Alimentos , Gelatina , Glucanos , Estruturas Metalorgânicas , Óleos Voláteis , Gelatina/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Cinnamomum zeylanicum/química , Embalagem de Alimentos/métodos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Glucanos/química , Glucanos/farmacologia , Conservação de Alimentos/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Carne/microbiologia , Animais , Testes de Sensibilidade Microbiana
16.
Int J Biol Macromol ; 268(Pt 1): 131775, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657922

RESUMO

Active packaging is a novel technology that utilizes active materials to interact with products and the environment, improving food shelf life. The purpose of this work was to fabricate a multifunctional film using Litsea cubeba essential oil (LC-EO) (1 %, 3 %, 5 %, and 7 %) as the active ingredient and pullulan(P)/tapioca starch (TS) as the carrier material. Adding essential oil improves the films properties, such as barrier ability, anti-oxidant, and antibacterial activity. However, tensile strength (TS) and elongation at break (EAB) were slightly reduced from 28.94 MPa to 11.29 MPa and 15.36 % to 12.19 %. The developed PTS3% films showed the best performance in mechanical properties, especially EAB (14.26 %), WVP (3.26 %) and OP (3.13 %), respectively. The inhibitory zone diameters in the agar-well diffusion test were 18.59 mm for Staphylococcus aureus and 17.32 mm for Escherichia coli. Further study was conducted to compare the preservation effects of film with low-density polyethylene bag (LDPE) on chilled beef. Remarkably, PTS3% film decreased the bacterial population in beef meat while maintaining the pH, color, texture, and TBARS levels within an acceptable range for ten days of storage at 4 °C rather than in a low-density polyethylene bag. The outcomes indicated the potential of PTS3% films in food packaging applications.


Assuntos
Antibacterianos , Embalagem de Alimentos , Conservação de Alimentos , Glucanos , Litsea , Manihot , Óleos Voláteis , Amido , Amido/química , Glucanos/química , Glucanos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Conservação de Alimentos/métodos , Manihot/química , Embalagem de Alimentos/métodos , Litsea/química , Staphylococcus aureus/efeitos dos fármacos , Animais , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Antioxidantes/química , Antioxidantes/farmacologia , Resistência à Tração , Carne/microbiologia
17.
Carbohydr Polym ; 336: 122102, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670773

RESUMO

Skin wounds are susceptible to infection, leading to severe inflammatory reactions that can progress to chronic wounds, ultimately causing significant physical and mental distress to the patient. In this study, we propose an injectable composite hydrogel achieved through one-pot gelation of oxidized xyloglucan (OXG), cationic polyamide ε-poly-l-lysine (EPL), and surface amino-rich silicon nanoparticles (SiNPs). OXG exhibits commendable anti-inflammatory properties and provides crosslinking sites. SiNPs serve as mechanically reinforced crosslinkers, facilitating the construction of a dynamic Schiff base network. SiNPs significantly reduced the gelation time to 3 s and tripled the storage modulus of the hydrogels. Additionally, the combination of EPL and SiNPs demonstrated synergistic antimicrobial activity against both S. aureus and E. coli. Notably, the hydrogel effectively halted liver bleeding within 30 s. The hydrogel demonstrated outstanding shear-thinning and self-healing properties, crucial considerations for the design of injectable hydrogels. Furthermore, its efficacy was evaluated as a wound dressing in a mouse model with S. aureus infection. The results indicated that, compared to commercial products, the hydrogel exhibited a shorter wound healing time, decreased inflammation, thinner epithelium, increased hair follicles, enhanced neovascularization, and more substantial collagen deposition. These findings strongly suggest the promising potential of the proposed hydrogel as an effective wound dressing for the treatment of infected wounds.


Assuntos
Antibacterianos , Escherichia coli , Glucanos , Hidrogéis , Nanopartículas , Polilisina , Staphylococcus aureus , Cicatrização , Xilanos , Glucanos/química , Glucanos/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Xilanos/química , Xilanos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Polilisina/química , Polilisina/farmacologia , Camundongos , Nanopartículas/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Reagentes de Ligações Cruzadas/química , Infecção dos Ferimentos/tratamento farmacológico , Masculino
18.
BMC Cancer ; 24(1): 339, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486205

RESUMO

BACKGROUND: Beta-(1,3)(1,6)-D-glucan is a complex polysaccharide, which is found in the cell wall of various fungi, yeasts, bacteria, algae, barley, and oats and has immunomodulatory, anticancer and antiviral effects. In the present study, we investigated the effect of beta-(1,3)(1,6)-D-glucan derived from yeast on the proliferation of primary NK cells and breast cancer cell lines in 2D and 3D models, and on the cytotoxicity of primary NK cells against breast cancer cell lines in 2D and 3D models. METHODS: In this study, we investigated the effects of different concentrations of yeast-derived beta-(1→3)(1→6)-D-glucan on the proliferation and cytotoxicity of human NK cells and breast cancer cell lines in 2D and 3D models using the XTT cell proliferation assay and the CellTiter-Glo® 2.0 assay to determine the cytotoxicity of human NK cells on breast cancer cell lines in 2D and 3D models. RESULTS: We found that the co-incubation of NK cells with beta-glucan in the absence of IL2 at 48 h significantly increased the proliferation of NK cells, whereas the co-incubation of NK cells with beta-glucan in the presence of IL2 (70 U/ml) increased the proliferation of NK cells but not significantly. Moreover, beta-glucan significantly inhibited the proliferation of breast cancer cell lines in 2D model and induced a weak, non-significant growth inhibitory effect on breast cancer multicellular tumor spheroids (3D). In addition, the cytotoxicity of NK cells against breast cancer cell lines was examined in 2D and 3D models, and beta-glucan significantly increased the cytotoxicity of NK cells against MCF-7 (in 2D). CONCLUSIONS: Yeast derived beta-(1,3)(1,6)-D-glucan could contribute to the treatment of cancer by enhancing NK cell immune response as well as contributing to inhibition of breast cancer cell growth.


Assuntos
Neoplasias da Mama , beta-Glucanas , Humanos , Feminino , Células MCF-7 , Glucanos/farmacologia , Neoplasias da Mama/patologia , Saccharomyces cerevisiae , Interleucina-2 , Células Matadoras Naturais , beta-Glucanas/farmacologia
19.
Int J Biol Macromol ; 266(Pt 2): 131000, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521333

RESUMO

In recent years, the development of probiotic film by incorporating probiotics into edible polymers has attracted significant research attention in the field of active packaging. However, the influence of the external environment substantially reduces the vitality of probiotics, limiting their application. Therefore, to improve the probiotic activity, this study devised a novel nanofiber film incorporating chia mucilage protection solution (CPS), gum arabic (GA), pullulan (PUL), and Lactobacillus bulgaricus (LB). SEM images indicated the successful preparation of the nanofiber film incorporating LB. CPS incorporation significantly improved the survival ability of LB, with a live cell count reaching 7.62 log CFU/g after 28 days of storage at 4 °C - an increase of 1 log CFU/g compared to the fiber film without CPS. The results showed that the fiber film containing LB inhibited Escherichia coli and Staphylococcus aureus. Finally, the novel probiotic nanofiber film was applied to beef. The results showed that the shelf life of the beef during the experiments was extended for 2 days at 4 °C. Therefore, the novel probiotic film containing LB was suitable for meat preservation.


Assuntos
Antibacterianos , Glucanos , Goma Arábica , Nanofibras , Nanofibras/química , Glucanos/química , Glucanos/farmacologia , Goma Arábica/química , Antibacterianos/farmacologia , Antibacterianos/química , Salvia/química , Lactobacillus delbrueckii , Probióticos/química , Animais , Conservação de Alimentos/métodos , Carne Vermelha/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Mucilagem Vegetal/química , Escherichia coli/efeitos dos fármacos , Bovinos , Embalagem de Alimentos/métodos
20.
Int J Biol Macromol ; 266(Pt 1): 131170, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554906

RESUMO

Skin wound healing is a complex and dynamic process involving hemostasis, inflammatory response, cell proliferation and migration, and angiogenesis. Currently used wound dressings remain unsatisfactory in the clinic due to the lack of adjustable mechanical property for injection operation and bioactivity for accelerating wound healing. In this work, an "all-sugar" hydrogel dressing is developed based on dynamic borate bonding network between the hydroxyl groups of okra polysaccharide (OP) and xyloglucan (XG). Benefiting from the reversible crosslinking network, the resulting composite XG/OP hydrogels exhibited good shear-thinning and fast self-healing properties, which is suitable to be injected at wound beds and filled into irregular injured site. Besides, the proposed XG/OP hydrogels showed efficient antioxidant capacity by scavenging DPPH activity of 73.9 %. In vivo experiments demonstrated that XG/OP hydrogels performed hemostasis and accelerated wound healing with reduced inflammation, enhanced collagen deposition and angiogenesis. This plant-derived dynamic hydrogel offers a facile and effective approach for wound management and has great potential for clinical translation in feature.


Assuntos
Antioxidantes , Hidrogéis , Neovascularização Fisiológica , Polissacarídeos , Cicatrização , Cicatrização/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Animais , Polissacarídeos/química , Polissacarídeos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Abelmoschus/química , Glucanos/química , Glucanos/farmacologia , Xilanos/química , Xilanos/farmacologia , Camundongos , Ratos , Masculino , Humanos , Angiogênese
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