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1.
Artigo em Inglês | MEDLINE | ID: mdl-28465707

RESUMO

Periostracum cicadae is widely used for the treatment of skin diseases such as eczema, pruritus, and itching. The current study sought to evaluate the effect of P. cicadae extract on ultraviolet B (UVB) irradiation and identify the mechanisms involved. Photodamage-protective activity of P. cicadae extracts against oxidative challenge was screened using HaCaT keratinocytes. P. cicadae extracts did not affect cell viability but decreased reactive oxygen species (ROS) production. The extract attenuates the expression of interleukin-6 (IL-6), matrix metalloproteinase-2 (MMP-2), and MMP-9 in UVB-treated HaCaT cells. Also, P. cicadae abrogated UVB-induced activation of NF-κB, p53, and activator protein-1 (AP-1). The downmodulation of IL-6 by P. cicadae was inhibited by the p38 inhibitor (SB203580) or JNK inhibitor (SP600125). Moreover, the extract attenuated the expression of NF-κB and induced thrombomodulin in keratinocytes and thereby effectively downregulated inflammatory responses in the skin. The nuclear accumulation and expression of NF-E2-related factor (Nrf2) were increased by P. cicadae treatment. Furthermore, treatment with P. cicadae remarkably ameliorated the skin's structural damage induced by irradiation. This study demonstrates that P. cicadae may protect skin cells against oxidative insult by modulating ROS concentration, IL-6, MMPs generation, antioxidant enzymes activity, and cell signaling pathways.

2.
Int Microbiol ; 18(1): 61-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26415668

RESUMO

The protective effects of encapsulation on the survival of Lactobacillus reuteri and the retention of the bacterium's probiotic properties under simulated gastrointestinal conditions were investigated. Viable counts and the remaining probiotic properties of calcium (Ca)-alginate encapsulated (A group), chitosan-Ca-alginate encapsulated (CA group), and unencapsulated, free L. reuteri (F group) were determined. Encapsulation improved the survival of L. reuteri subjected to simulated gastrointestinal conditions, with the greatest protective effect achieved in the CA group. The degree of cell membrane injury increased with increasing bile salt concentrations at constant pH, but the extent of injury was less in the encapsulated than in the free cells. Adherence rates were, in descending order: CA (0.524%)>A (0.360%)>F (0.275%). Lactobacillus reuteri cells retained their antagonistic activity toward Listeria monocytogenes even after incubation of the lactobacilli under simulated gastrointestinal conditions. Displacement of the pathogen by cells released from either of the encapsulation matrices was higher than that by free cells. The safety of L. reuteri was demonstrated in an in vitro invasion assay.


Assuntos
Alginatos/química , Cálcio/química , Quitosana/química , Trato Gastrointestinal/microbiologia , Limosilactobacillus reuteri/fisiologia , Probióticos/administração & dosagem , Ácidos e Sais Biliares , Composição de Medicamentos , Viabilidade Microbiana , Microesferas
3.
Int. microbiol ; 18(1): 61-69, mar. 2015. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-141145

RESUMO

The protective effects of encapsulation on the survival of Lactobacillus reuteri and the retention of the bacterium’s probiotic properties under simulated gastrointestinal conditions were investigated. Viable counts and the remaining probiotic properties of calcium (Ca)-alginate encapsulated (A group), chitosan-Ca-alginate encapsulated (CA group), and unencapsulated, free L. reuteri (F group) were determined. Encapsulation improved the survival of L. reuteri subjected to simulated gastrointestinal conditions, with the greatest protective effect achieved in the CA group. The degree of cell membrane injury increased with increasing bile salt concentrations at constant pH, but the extent of injury was less in the encapsulated than in the free cells. Adherence rates were, in descending order: CA (0.524%) > A (0.360%) > F (0.275%). Lactobacillus reuteri cells retained their antagonistic activity toward Listeria monocytogenes even after incubation of the lactobacilli under simulated gastrointestinal conditions. Displacement of the pathogen by cells released from either of the encapsulation matrices was higher than that by free cells. The safety of L. reuteri was demonstrated in an in vitro invasion assay (AU)


No disponible


Assuntos
Limosilactobacillus reuteri/crescimento & desenvolvimento , Listeria monocytogenes/patogenicidade , Probióticos/farmacocinética , Técnicas In Vitro , Quitosana , Compostos de Cálcio
4.
J Microbiol Methods ; 107: 138-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25281473

RESUMO

The potential probiotic properties of lactic acid bacteria (LAB) after treatment with gastrointestinal (GI) conditions were investigated. Some LAB strains that survived simulated GI treatment retained their adhesiveness and antagonism against the pathogen. Therefore pre-challenging LAB with simulated GI conditions is a suitable way for potential probiotic studies.


Assuntos
Trato Gastrointestinal/microbiologia , Lactobacillaceae/fisiologia , Probióticos , Aderência Bacteriana/efeitos dos fármacos , Ácidos e Sais Biliares/farmacologia , Linhagem Celular , Humanos , Lactobacillaceae/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , beta-Galactosidase/metabolismo
5.
J Nutr Biochem ; 20(2): 132-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18547794

RESUMO

The main purpose of this study was to evaluate changes in brain sulfur-containing amino acid (SCAA) metabolism to determine whether taurine intervened under continuous alcohol intake. We fed 80 male Sprague-Dawley rats 30% alcohol-containing water for 4 weeks. Eighty animals were divided into two groups (with or without 2 g/kg body weight taurine supplementation), and five were killed every week in each group for monitoring SCAA changes in the brain, liver, kidneys and heart. Results indicated that the plasma alcohol concentration increased from Weeks 1-4; however, animals with taurine supplementation showed a lower plasma concentration of ethanol in Week 2. As to SCAA concentrations, cysteine and taurine were both lower after a week of alcohol ingestion in the brain and plasma; the same declining trend was shown in the liver in Week 2. In contrast, plasma and hepatic concentrations of homocysteine were elevated in Week 2, and the plasma S-adenosylmethionine (SAM)/S-adenosylhomocysteine (SAH) ratio also decreased in Week 1. Furthermore, the key cofactor of transsulfuration, pyridoxal-5'-phosphate, significantly declined in the plasma after a week of the ethanol intervention, whereas an increase was observed in brain tissue. Under taurine supplementation, some recoveries were shown by delaying taurine depletion to Week 2, increasing the SAM/SAH ratio and elevating plasma and brain levels of vitamin B6 in Week 2. In conclusion, daily consumption of 30% alcohol interfered with SCAA metabolism, thus decreasing taurine's role in neurotransmission. The possible mechanism involved might be that ethanol interrupts the production of cysteine, which is the upstream SCAA of taurine, thus decreasing the homocysteine level. Additionally, taurine supplementation delayed this process.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Etanol/farmacologia , Metionina/metabolismo , Taurina/farmacologia , Animais , Cisteína/metabolismo , Fosfato de Piridoxal/metabolismo , Ratos , Ratos Sprague-Dawley , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Taurina/análogos & derivados , Taurina/metabolismo
7.
J Microbiol Methods ; 70(3): 561-4, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17617480

RESUMO

Lactobacillus reuteri shows certain beneficial effects to human health and is recognized as a probiotic. However, its application in frozen foods is still not popular because of its low survival during freezing and frozen storage. Cell immobilization technique could effectively exert protection effects to microbial cells in order to enhance their endurance to unfavorable environmental conditions as well as to improve their viability and cell concentration. Ca-alginate and kappa-carrageenan were used to immobilize L. reuteri in this research, and the immobilized cells were exposed to different freezing temperatures, i.e. -20 degrees C, -40 degrees C, -60 degrees C, -80 degrees C, and stored at -40 degrees C and -80 degrees C for 12 weeks. The objectives were to study the protection effects of cell immobilization against the adverse conditions of freezing and frozen storage, and the effects of freezing temperatures to the immobilized cells. Cell immobilization was used to raise the survival of L. reuteri during freezing and frozen storage in order to develop frozen foods with the probiotic effects of L. reuteri. Results indicated that immobilized L. reuteri possessed better survival in both freezing and frozen storage. The survival of immobilized L. reuteri was higher than that of free cells, and the effects of lower freezing temperature were better than higher freezing temperature. The immobilization effects of Ca-alginate were found to be superior to kappa-carrageenan. Cell immobilized L. reuteri exhibits potential to be used in frozen foods.


Assuntos
Criopreservação/métodos , Alimentos Congelados/microbiologia , Limosilactobacillus reuteri , Probióticos , Alginatos/química , Carragenina/química , Células Imobilizadas/fisiologia , Crioprotetores/farmacologia , Congelamento , Ácido Glucurônico/química , Ácidos Hexurônicos/química
8.
Curr Microbiol ; 54(5): 396-404, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17387552

RESUMO

The basic characteristics of the spore-forming lactic acid bacterium, Sporolactobacillus inulinus BCRC 14647, was evaluated in vitro for its potential probiotic properties. Assessments including acid and bile salt tolerance, adhesiveness, and antagonistic effects on pathogenic Salmonella enteritidis BCRC 10744, as well as inhibition factors of spent culture supernatant (SCS) and an invasion assay, were conducted using Lactobacillus acidophilus BCRC 10695 and two bifidobacteria (Bifidobacterium bifidum BCRC 14615 and B. longum BCRC 11847) as a reference. In the results, S. inulinus spores presented significantly higher survival rates than the vegetative cell form in acidic conditions as well as the reference bifidobacteria. However, L. acidophilus showed the highest viability among all tested strains. Similar results were found in the bile tolerance test. Compared with the reference strains, the vegetative cell form of S. inulinus possessed a proper adhesive characteristic (71.7 bacteria/field for S. inulinus and 91.3 and 45.7 bacteria/field for B. bifidum and B. longum, respectively). In the adhesion assay, both the spore form of S. inulinus (17.1 bacteria/field) and the negative control, L. bulgaricus BCRC 14009 (5.9 bacteria/field), displayed nonadhesive traits. The vegetative cells of S. inulinus and its SCS both dramatically decrease the adhesion of S. enteritidis to Caco-2 cells; meanwhile, the SCS of S. inulinus vegetative cells inhibited the growth of S. enteritidis in the inhibition zone test. The existing inhibition factor could be assumed to be lactic acid in the SCS. From the results of the invasion assay, S. inulinus showed high safety properties. In conclusion, based on these in vitro evaluations, results suggest that S. inulinus presents probiotic features of great potential in the vegetative cell form.


Assuntos
Bacillaceae/fisiologia , Probióticos , Ácidos/farmacologia , Bacillaceae/efeitos dos fármacos , Aderência Bacteriana , Bifidobacterium/fisiologia , Ácidos e Sais Biliares/farmacologia , Células CACO-2 , Humanos , Concentração de Íons de Hidrogênio , Lactobacillaceae , Lactobacillus acidophilus/fisiologia , Viabilidade Microbiana , Esporos Bacterianos/fisiologia
9.
Int J Food Microbiol ; 91(2): 215-20, 2004 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-14996466

RESUMO

Fermentation media were prepared by using banana as the raw material, and cell immobilization of Lactobacillus acidophilus by kappa-carrageenan entrapment was applied to enhance the fermentation efficiency. Gel beads of diameters around 3.0 mm were prepared for the immobilized cells, ripe bananas were used for preparation of media, and both free and immobilized cells were employed to carry out the fermentation for 80 h. Cells leaked out from the gel beads and proliferated in the medium solution during the fermentation of immobilized cells. The final viable cell number reached 10(5) CFU/ml in the medium suspension, over 10(8) CFU/(ml gel) in gel beads for the immobilized cell fermentation and around 10(6) CFU/ml for the free cell fermentation. Immobilized cells withstand the adverse conditions in banana media resulting in better fermentation efficiency compared to free cells. Variation of fructooligosaccharides (FOS) in banana media was not significant in immobilized cell fermentation compared to free cell. Immobilized L. acidophilus fermented banana medium was found to possess synbiotic properties.


Assuntos
Fermentação , Tecnologia de Alimentos , Lactobacillus/metabolismo , Musa/metabolismo , Carragenina/farmacologia , Células Imobilizadas , Contagem de Colônia Microbiana , Meios de Cultura/química , Microbiologia de Alimentos , Lactobacillus/crescimento & desenvolvimento , Probióticos , Fatores de Tempo
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