Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Biol Macromol ; : 133214, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897526

RESUMO

The effects of selenium biofortification methods involving sodium selenite and selenium yeast on the structural characteristics, antioxidant activity and binding capacity of Pleurotus eryngii polysaccharides were investigated. Sodium selenite Se-enriched Pleurotus eryngii polysaccharides (Se-SPEP), selenium yeast Se-enriched Pleurotus eryngii polysaccharides (Se-YPEP), and Pleurotus eryngii polysaccharides (PEP) had Se contents of 20.548 ±â€¯1.561, 19.822 ±â€¯0.613, and 0.052 ±â€¯0.016 µg/g, respectively. Compared with PEP, Se-SPEP and Se-YPEP had lower molecular weight and contained the same monosaccharides in varying molar ratios. The results of FT-IR, PS, ZP, and SEM indicated significant alterations in structural characteristics following selenium biofortification. Se-PEPs exhibited superior activity against ABTS, DPPH, and ·OH radicals, as well as the higher binding capacity for Cd2+ and Cu2+ compared to natural polysaccharides. The binding capacity of the polysaccharides for Cd2+ and Cu2+ was higher at pH 6.8 compared to pH 2.0, while the opposite was observed for Pb2+. Furthermore, Se-PEPs exhibited a significantly higher binding capacity for Cd2+ and Cu2+ at both pH levels compared to natural polysaccharides (P < 0.05). Se-YPEP displayed higher antioxidant activity than Se-SPEP, with their binding capacities reversed. These data indicated that selenium biofortification methods have different positive impacts on the structure and activity of polysaccharides compared to natural polysaccharides, making Se-PEPs promising dietary supplements for safeguarding the body against the risks posed by food-derived heavy metals.

2.
Front Nutr ; 9: 930506, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35811978

RESUMO

The acute and prolonged diuretic effects of coconut water (CW) and the underlying mechanism were investigated with a saline-loaded rat model. In an acute diuretic experiment, CW could significantly increase urine excretion. In addition, the treatment of CW significantly increased urinary sodium and chloride ions, thereby considerably increasing the excretion of NaCl. However, the calcium concentration and pH value were not affected. In the prolonged diuretic experiment, CW dramatically increased the urine output and urine electrolyte concentrations (Na+, K+, and Cl-). Furthermore, CW could suppress the activation of renin-angiotensin-aldosterone system by decreasing serum antidiuretic hormone, angiotensin II, and aldosterone levels, and significantly increasing the serum atriopeptin level. CW treatment significantly reduced the mRNA expressions and protein levels of aquaporin 1 (AQP1), AQP2, and AQP 3. This report provided basic data for explaining the natural tropical beverage of CW as an alternative diuretic agent.

3.
Food Chem ; 347: 129043, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33476919

RESUMO

In this study, the properties difference of Tilapia (Oreochromis Niloticus) skin collagen peptide chelate zinc prepared by zinc sulfate (P-Zn-S) and zinc lactate (P-Zn-L) were investigated. The results indicated that compared with P-Zn-L, P-Zn-S exhibited higher Zn-chelating capacity and different structural morphology, which may closely relate to the composition amino acid of Asp, Glu, His, Lys, Arg, Cys and Pro. FTIR and UV-Vis analysis indicated that different zinc sources could influence the metal ligands and the types of amino acid residues which were involved in chelation reaction. P-Zn-L exhibited better zinc solubility and had higher dialyzable zinc than P-Zn-S, indicating that P-Zn-L had better zinc bioaccessibility. These results suggested that P-Zn-L with a granular structure could reduced gastric stability, promoted intestinal release, and was beneficial to zinc absorption, which can be used as dietary zinc carriers.


Assuntos
Quelantes/química , Ciclídeos/metabolismo , Colágeno/química , Lactatos/química , Peptídeos/química , Sulfato de Zinco/química , Aminoácidos/análise , Aminoácidos/química , Animais , Digestão , Concentração de Íons de Hidrogênio , Peptídeos/metabolismo , Pele/metabolismo , Solubilidade
4.
J Agric Food Chem ; 69(1): 246-258, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382620

RESUMO

Polyphenol can improve osteoporosis and is closely associated with gut microbiota, while the mechanism and the relationship among polyphenol, osteoporosis, and gut microbiota colonization remain unclear. Here, an osteoporosis rat model established by ovariectomy was employed to investigate the improving mechanism of arecanut (Areca catechu L.) seed polyphenol (ACP) on osteoporosis by regulating gut microbiota. We analyzed the bone microstructure, Paneth cells, regulating microbial protein (lysozyme (LYZ)), proinflammatory cytokines, macrophage infiltration levels, and gut microbial communities in a rat. ACP improved the trabecular microstructure compared to OVX, including the increased trabecular number (Tb.N) (P < 0.01) and trabecular thickness (Tb.Th) (P < 0.001) and decreased trabecular separation (Tb.Sp) (P < 0.01). At the phylum level, Bacteroidetes was increased after ovariectomy (P < 0.001) and Firmicutes and Proteobacteria were increased in ACP (P < 0.001). Antiosteoporosis groups with lower LYZ and Paneth cells (P < 0.001) showed that the microbiota Alistipes, which have a negative effect on bone metabolism were decreased in ACP (P < 0.001). Altogether, these studies showed that the estrogen deficiency could induce the shedding of Paneth cells, which leads to the decrease of LYZ, while ACP could increase the LYZ expression by maintaining the population of Paneth cells in an estrogen-deficient host, which were implicated in gut microbiota regulation and improved osteoporosis by controlling the inflammatory reaction.


Assuntos
Areca/química , Microbioma Gastrointestinal/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Densidade Óssea/efeitos dos fármacos , Estrogênios/deficiência , Feminino , Humanos , Osteoporose/imunologia , Osteoporose/microbiologia , Osteoporose/fisiopatologia , Ratos , Sementes/química
5.
J Agric Food Chem ; 68(6): 1621-1633, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967468

RESUMO

Collagen peptides can promote wound healing and are closely related to microbiome colonization. We investigated the relationship among collagen peptides, wound healing, and wound microflora colonization by administering the murine wound model with Salmo salar skin collagen peptides (Ss-SCPs) and Tilapia nilotica skin collagen peptides (Tn-SCPs). We analyzed the vascular endothelial growth factor (VEGF), fibroblast growth factors (ß-FGF), pattern recognition receptor (NOD2), antimicrobial peptides (ß-defence14, BD14), proinflammatory (TNF-α, IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines, macrophages, neutrophil infiltration levels, and microbial communities in the rat wound. The healing rates of the Ss-SCP- and Tn-SCP-treated groups were significantly accelerated, associated with decreased TNF-α, IL-6, and IL-8 and upregulated BD14, NOD2, IL-10, VEGF, and ß-FGF. Accelerated healing in the collagen peptide group shows that the wound microflora such as Leuconostoc, Enterococcus, and Bacillus have a positive effect on wound healing (P < 0.01). Other microbiome species such as Stenotrophomonas, Bradyrhizobium, Sphingomonas, and Phyllobacterium had a negative influence and decreased colonization (P < 0.01). Altogether, these studies show that collagen peptide could upregulate wound NOD2 and BD14, which were implicated in microflora colonization regulation in the wound tissue and promoted wound healing by controlling the inflammatory reaction and increasing wound angiogenesis and collagen deposition.


Assuntos
Colágeno/química , Proteínas de Peixes/química , Microbiota/efeitos dos fármacos , Proteína Adaptadora de Sinalização NOD2/genética , Peptídeos/administração & dosagem , Pele/química , Ferimentos e Lesões/fisiopatologia , beta-Defensinas/genética , Administração Cutânea , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Ciclídeos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/imunologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Masculino , Camundongos , Proteína Adaptadora de Sinalização NOD2/imunologia , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Salmo salar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/imunologia , Ferimentos e Lesões/microbiologia , beta-Defensinas/imunologia
6.
Nat Commun ; 10(1): 5109, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704916

RESUMO

Great efforts have been made in the activation of a C(alkenyl)-H bond vicinal to the directing group to proceed via five- or six-membered endo-metallocycles. In stark contrast, functionalization of a C(alkenyl)-H bond geminal to the directing group via exo-metallocycle pathway continued to be elusive. Here we report the selective transformation of an olefinic C-H bond that is geminal to the directing group bearing valuable hydroxyl, carbamate or amide into a C-C bond, which proceeds through four- to eight-membered exo-palladacycles. Compared to the reported mechanisms proceeding only through six-membered exo-palladacycles via N,N-bidentate chelation, our weak and O-monodentate chelation-assisted C(alkenyl)-H activations tolerate longer or shorter distances between the olefinic C-H bonds and the coordinating groups, allowing for the functionalizations of many olefinic C-H bonds in alkenyl alcohols, carbamates and amides. The synthetic applicability has been demonstrated by the preparative scale and late-stage C-H functionalization of steroid and ricinoleate derivatives.

7.
Org Lett ; 21(20): 8219-8224, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31589451

RESUMO

A range of Ru-, Rh-, or Pd-catalyzed vinylic C-H/C-H cross-coupling reactions of olefins have been demonstrated to provide 1,3-dienes, using a quantitative amount of metal oxidants. Although transfer hydrogenation and C-H alkenylation are two important areas that evolved independently, we herein report the first iridium-catalyzed cross-coupling reactions of alkenes by integration of directed C(alkenyl)-H alkenylation and transfer hydrogenation to obviate the usage of a metal oxidant, employing a hydrogen acceptor such as inexpensive chloranil.

8.
Chem Commun (Camb) ; 55(66): 9757-9760, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31353380

RESUMO

An iridium-catalyzed C-H allylation of acrylamides with conjugated dienes was developed, using NH-Ts amide as the directing group. The ligand- and additive-free protocol provided a convenient and atom economic synthesis of branched 1,4-diene skeletons, enabling the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3. The utility of this protocol is also demonstrated by a preparative scale, as well as C-H functionalization of artemisic amide. Furthermore, NH-Ts amide was efficiently removed by methylation and hydrolysis procedures to provide 1,4-dienoic acid.

9.
Org Lett ; 21(12): 4868-4872, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31188008

RESUMO

Although a range of transition-metal-catalyzed cross-coupling reactions of alkenes and alkynes have been developed to produce valuable conjugated dienes, extension of these reactions to iridium catalysis has yet to be demonstrated. The first iridium-catalyzed alkene-alkyne cross-coupling reactions have been realized under ligand- and additive-free conditions. A wide range of acrylamides and alkynes could be used as coupling partners, providing branched ( Z, Z)-butadiene skeletons with excellent site- and stereoselectivities. The utility of this approach is also demonstrated by preparative-scale and C-H functionalization of perillic and artemisic amides.

10.
Chem Commun (Camb) ; 55(6): 826-829, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30574981

RESUMO

A ruthenium-catalyzed C-H alkenylation of aroylsilanes with electron-deficient alkenes was developed, using acylsilane as the directing group. The mild reaction conditions enable the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3, providing a convenient and highly effective method for the synthesis of styrene derivatives bearing acylsilane. Steroid and heterocycles such as furan and thiophene were also well tolerated. Furthermore, acylsilane was efficiently converted to the corresponding aldehyde or carboxylic acid.

11.
Org Lett ; 19(10): 2498-2501, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28481556

RESUMO

A ruthenium-catalyzed direct cross-coupling between alkenes and alkynes via directed C-H bond activation is described. By using N,N-disubstituted aminocarbonyl as a directing group, this oxidant-free and atom-economic protocol resulted in high efficiency and good stereoselectivities, which opens a novel synthetic passway for access to substituted (Z,Z)-butadiene skeletons.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA