Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Food Sci Biotechnol ; 33(11): 2611-2621, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39144197

RESUMO

Phlomoides umbrosa Turczaninow (PU), a traditional Korean medicinal herb, exhibits osteogenic and anti-inflammatory effects. This research explored the effect of PU extracts on hyperimmune responses within the respiratory tract using lipopolysaccharide-stimulated RAW 264.7 cells and an ovalbumin-induced hyper-responsiveness model. The inflammatory cytokines, protein expression linked to airway inflammation, antioxidant enzyme activity, histopathological observation, and expectorant activity were measured. The results revealed that PU treatment led to a concentration-dependent reduction in Th2 cytokines and the expression of nuclear factor (NF)-κB, phosphatase-tensin homolog, mitogen-activated protein kinase (MAPK), and inducible nitric oxide synthase (iNOS). Simultaneously, antioxidant enzyme activity increased. Furthermore, PU exhibited substantial enhancements in lung tissue condition and expectorant activity relative to the allergic rhinitis-induced group. These findings indicate the potential of PU to mitigate airway inflammation and excessive mucus production by suppressing NF-κB, MAPK, and iNOS pathways. Consequently, PU emerges as a promising anti-inflammatory agent for respiratory tract applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-024-01521-3.

2.
Polymers (Basel) ; 15(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38139979

RESUMO

The interest in research and development for additive manufacturing (AM) processes has grown significantly over the last years and attracts both industry and academia alike. Among the available AM technologies, stereolithography (SLA) is one of the most discussed, researched, and employed. On the other hand, being based on thermoset resins, all the limitations of this typology of materials still apply, limiting the range of applications of this highly versatile process. To overcome these limitations, especially brittleness, this research analyzes the effects of Tungsten (W) micro-size (average size 1 µm) particles reinforcement on a methacrylate base material. First, the manufacturing process for creating the W-reinforced methacrylate material is presented and investigated to define the effect of pre- and post-processing operations on the quality of the pre-cured solution considering 4% and 10% wt. W particles concentrations. Afterward, tensile, compressive, and impact specimens were manufactured with both concentrations and compared with the experimental results from clear (unfilled) resin-based specimens used as the benchmark. The addition of tungsten particles showed a strong improvement in the impact strength of the methacrylate base material, quantified in 28% for the 4% and 55% for the 10% wt., respectively, although at the expense of a slight reduction in elastic and yield properties on average -12%. Furthermore, using Scanning Electron Microscope (SEM) analyses, the particle-matrix interaction was investigated, showing the interaction between the polymer matrix and the reinforcement and the mechanism by which the impact resistance is enhanced.

3.
Saudi J Biol Sci ; 28(9): 5115-5118, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34466089

RESUMO

Bifidobacterium bifidum BGN4 has been shown to improve the immune system by regulating interleukin (IL)-6 in RAW 264.7 macrophage cells. In this study, the dead cells of B. bifidum BGN4 were produced by enzymatic and physical processing to enhance the inhibition properties of pro-inflammatory cytokines using lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Notably, the secretion levels of cytokines such as interleukin (IL)-1ß, IL-6, IL-8, and tumor necrosis factor (TNF)-α were decreased by the cell-wall disrupted extracts compared to heat-killed cells. The result suggests that the exposed interior-surface of B. bifidum BGN4 has a potential ability to regulate the immune-responses in the gastrointestinal tract due to major substances in inside-cell wall such as peptidoglycan and teichoic acids. In conclusion, the lysed and disrupted cells from the inside out of B. bifidum BGN4 have anti-inflammatory properties as paraprobiotic agents to control chronic inflammatory related-diseases.

4.
Enzyme Microb Technol ; 135: 109505, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32146930

RESUMO

Amylosucrase (ASase) has great industrial potential owing to its multifunctional activities, including transglucosylation, polymerization, and isomerization. In the present study, the properties of Deinococcus geothermalis ASase (DGAS) expressed in Corynebacterium glutamicum (cDGAS) and purified via Ni-NTA affinity chromatography were compared to those of DGAS expressed in Escherichia coli (eDGAS). The pH profile of cDGAS was similar to that of eDGAS, whereas the temperature profile of cDGAS was lower than that of eDGAS. The melting temperature of both enzymes did not differ significantly. Interestingly, polymerization activity was slightly lower in cDGAS than in eDGAS, whereas luteolin (an acceptor molecule) transglucosylation activity in cDGAS was 10 % higher than that in eDGAS. Analysis of protein secondary structure via circular dichroism spectroscopy revealed that cDGAS had a lower strand/helix ratio than eDGAS. The present results indicate that cDGAS is of greater industrial significance than eDGAS.


Assuntos
Proteínas de Bactérias/metabolismo , Corynebacterium glutamicum/metabolismo , Deinococcus/enzimologia , Glucosídeos/biossíntese , Glucosiltransferases/metabolismo , Luteolina/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Corynebacterium glutamicum/genética , Deinococcus/genética , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Glucosiltransferases/química , Glucosiltransferases/genética , Engenharia Metabólica
5.
PLoS One ; 13(11): e0207466, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30452462

RESUMO

α-Flavone glycosides have beneficial properties for applications in the pharmaceutical, cosmetic, and food industries. However, their chemical syntheses are often limited by a low efficiency or scarcity of substrates. In this study, α-flavone glucosides were enzymatically synthesized by amylosucrase from Deinococcus geothermalis (DGAS) using sucrose and various flavones as a donor for glucosyl units and acceptors, respectively. Luteolin was the most effective acceptor in the transglucosylation reaction using DGAS among nine flavone materials (apigenin, chrysin, 6,7-dihydroxyflavone, homoorientin, 7-hydroxyflavone, isorhoifolin, luteolin, luteolin-3',7-diglucoside, and orientin). The highest production yield of luteolin glucoside was 86%, with a 7:1 molar ratio of donor to acceptor molecules, in 50 mM Tris-HCl buffer (pH 7) at 37°C for 24 h using 2 U of DGAS. The synthesized luteolin glucoside was identified as luteolin-4'-O-α-D-glucopyranoside with a glucose molecule linked to the C-4' position on the B-ring of luteolin via an α-glucosidic bond, as determined by 1H and 13C nuclear magnetic resonance. This result clearly confirmed that the glucosylated luteolin was successfully synthesized by DGAS and it can be applied as a functional ingredient. Furthermore, this approach using DGAS has the potential to be utilized for the synthesis of various glucosylated products using different types of polyphenols to enhance their functionalities.


Assuntos
Proteínas de Bactérias/química , Deinococcus/enzimologia , Glucosídeos/química , Glucosídeos/síntese química , Glucosiltransferases/química , Luteolina/química , Glicosilação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA