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3.
Microorganisms ; 12(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38257906

RESUMO

Isothiocyanates may have antibacterial activity against Helicobacter pylori, but there are different variables related to Brassicaceae-derived samples that could affect their efficacy. This work studied the influence of source variety, concentration, gastric digestion, and encapsulation of samples on their bioactive response against Helicobacter pylori. The antibacterial activity of raw sprouts (red cabbage and red radish) showed the highest antibacterial effect, which was consistent with a higher amount of isothiocyanates. It decreased with gastric digestion, regardless of sample encapsulation. By contrast, adult red radish leaves became antibacterial after gastric digestion. Antioxidant activity on H. pylori-infected gastric cells was similar in all samples and followed an equivalent pattern with the changes in isothiocyanates. Raw samples decreased intracellular reactive oxygen species production, but they lost this capacity after gastric digestion, regardless whether the compounds were free or encapsulated. Red cabbage sprouts, red radish sprouts, and red radish roots produced a decrease in nitric oxide production. It was consistent with a modulation of the inflammatory response and was associated to isothiocyanates concentration. Encapsulated sprout samples retained part of their anti-inflammatory activity after gastric digestion. Adult raw red radish leaves were not active, but after digestion, they became anti-inflammatory. The results obtained in this study have shown that several variables could have a significant impact on the bioactive properties of Brassicaceae-derived samples against H. pylori, providing a starting point for the design and standardization of samples with specific bioactivities (antibacterial, antioxidant, and anti-inflammatory) potentially useful for the treatment of H. pylori infection.

4.
Antioxidants (Basel) ; 11(10)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36290572

RESUMO

The main objective of this work is to evaluate the potential utility of an Achillea millefolium extract (yarrow extract, YE) in the control of H. pylori infection. The supercritical anti-solvent fractionation (SAF) process of YE allowed the obtaining of two different fractions: yarrow's precipitated fraction (YPF), enriched in most polar phenolic compounds (luteolin-7-O-glucoside, luteolin, and 3,5-dicaffeoylquinic acid), and yarrow's separator fraction (YSF), enriched in monoterpenes and sesquiterpenes, mainly containing camphor, artemisia ketone, and borneol. YE was effective in reducing reactive oxygen species (ROS) production in human gastric AGS cells by 16% to 29%, depending on the H. pylori strain. YPF had the highest inhibitory activity (38-40%) for ROS production. YE modulated the inflammatory response in AGS gastric cells, decreasing IL-8 production by 53% to 64%. This IL-8 inhibition also showed a strain-dependent character. YPF and YSF exhibited similar behavior, reducing IL-8 production, suggesting that both phenolic compounds and essential oils could contribute to IL-8 inhibition. YSF showed the highest antibacterial activity against H. pylori (6.3-7.1 log CFU reduction, depending on the strain) and lower MIC (0.08 mg/mL). Results obtained have shown that YE and SAF fractions (YPF and YSF) were effective as antioxidant, anti-inflammatory, and antibacterial agents regardless of the H. pylori strain characteristics.

5.
Foods ; 11(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35804647

RESUMO

The aim of this work was to evaluate the influence of in vitro gastric digestion of two olive leaf extracts (E1 and E2) on their chemical composition and bioactive properties against Helicobacter pylori (H. pylori), one of the most successful and prevalent human pathogens. HPLC-PAD/MS analysis and anti-inflammatory, antioxidant, and antibacterial activities of both olive leaf extracts were carried out before and after their in vitro gastric digestion. The results showed that gastric digestion produced modifications of the chemical composition and bioactive properties of both olive leaf extracts. The main compounds in the extract E1 were hydroxytyrosol and its glucoside derivatives (14,556 mg/100 g), presenting all the identified compounds a more polar character than those found in the E2 extract. E2 showed a higher concentration of less polar compounds than E1 extract, with oleuropein (21,419 mg/100 g) being the major component. Gastric digestion during the fasted state (pH 2) induced an overall decrease of the most identified compounds. In the extract E1, while the anti-inflammatory capacity showed only a slight decrease (9% of IL-8 production), the antioxidant properties suffered a drastic drop (23% of ROS inhibition), as well as the antibacterial capacity. However, in the extract E2, these changes caused an increase in the anti-inflammatory (19% of IL-8 production) and antioxidant activity (9% of ROS inhibition), which could be due to the hydrolysis of oleuropein and ligustroside into their main degradation products, hydroxytyrosol and tyrosol, but the antibacterial activity was reduced. Gastric digestion during fed state (pH 5) had less influence on the composition of the extracts, affecting in a lesser degree their anti-inflammatory and antioxidant activity, although there was a decrease in the antibacterial activity in both extracts similar to that observed at pH 2.

6.
Cancers (Basel) ; 14(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35158966

RESUMO

This study aimed to assess whether surgical practice had a significant impact on oncological outcomes among women who underwent robot-assisted radical hysterectomy for early-stage cervical cancer (≤IB1 or IIA1, FIGO 2009). The secondary objective was to audit the pre-surgical quality indicators (QI) proposed by the European Society of Gynaecological Oncology (ESGO). The top 5 of 10 centers in Spain and Portugal were included in the analysis. The hospitals were divided into group A (n = 118) and group B (n = 97), with recurrence rates of <10% and >10%, respectively. After balancing both groups using the propensity score, the ORs for all events were higher and statistically significant for group B (recurrences OR = 1.23, 95% CI = 1.13-1.15, p-value = 0.001; death OR = 1.10, 95% CI = 1.02-1.18, p-value = 0.012; disease-specific mortality ORr = 1.11, 95% CI = 1.04-1.19, p-value = 0.002). A higher surgical volume, higher participation in clinical trials, higher rate of MRI use for diagnosis, greater use of sentinel lymph node biopsies, and a favorable learning curve with low rates of early recurrences were observed among the centers with better oncological outcomes. These factors might have a significant impact on oncological outcomes not only after robot-assisted surgery, but also after laparoscopies and open surgeries in the treatment of cervical cancer.

7.
Antibiotics (Basel) ; 12(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36671227

RESUMO

Campylobacter spp. are the main cause of bacterial gastroenteritis worldwide, and broiler chicks are the main vector of transmission to humans. The high prevalence of Campylobacter in poultry meat and the increase of antibiotic resistant strains have raised the need to identify new antimicrobial agents. For this reason, the aim of the current study was to evaluate the antibacterial activity of two extracts of olive leaf against antibiotic-resistant Campylobacter strains (C. jejuni and C. coli) isolated from poultry food chain. The extracts of olive leaf (E1 and E2) were markedly different in their chemical compositions. While E1 was composed predominantly of highly hydrophilic compounds such as hydroxytyrosol and hydroxytyrosol glucosides (14,708 mg/100 g), E2 mainly contained moderately hydrophilic compounds, with oleuropein (20,471 mg/100 g) being prevalent. All Campylobacter strains exhibited similar antibiotic profiles, being resistant to ciprofloxacin and tetracycline. E1 showed strong antibacterial activity and reduced bacterial growth from 4.12 to 8.14 log CFU/mL, depending on the strain. Hydroxytyrosol was the main compound responsible, causing the inhibition of growth of Campylobacter strains at low concentrations (0.1-0.25 mg/mL). E2 demonstrated a lower antibacterial effect than E1, reducing growth from 0.52 to 2.49 log CFU/mL. The results of this study suggest that the optimization of the composition of olive-leaf extracts can provide improved treatment results against Campylobacter strains.

8.
Antioxidants (Basel) ; 10(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34943133

RESUMO

Helicobacter pylori (H. pylori) is one of the major human pathogens and the main cause of pathological damages that can progress from chronic gastritis to gastric cancer. During the colonization of gastric mucosa, this bacterium provokes a strong inflammatory response and subsequent oxidative process, which are associated with tissue damage. Therefore, the objective of this research was to evaluate the ability of two olive-leaf extracts (E1 and E2) to modulate the inflammatory response and oxidative stress in H. pylori-infected human gastric AGS cells. The obtained results showed that both extracts significantly decreased interleukin-8 (IL-8) secretion and reactive oxygen species (ROS) production in human gastric AGS cells. Both extracts also showed antibacterial activity against different H. pylori strains. HPLC-PAD-MS characterization demonstrated that extract E1 was mainly composed of highly hydrophilic compounds, such as hydroxytyrosol (HT) and its glucosides, and it was the most effective extract as an antibacterial agent. In contrast, extract E2 was composed mostly of moderately hydrophilic compounds, such as oleuropein (OLE), and it was more effective than extract E1 as an anti-inflammatory agent. Both extracts exhibited similar potential to decrease ROS production. These results show the importance of standardizing the extract composition according to the bioactive properties that should be potentiated.

9.
Antioxidants (Basel) ; 10(6)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208004

RESUMO

Helicobacter pylori (H. pylori) is a pathogenic bacteria identified as a potential risk factor for gastritis, gastric ulcers and gastric cancer. During the stomach colonization, H. pylori triggers a strong inflammatory response and subsequent oxidative stress, which are associated with tissue damage. For this reason, it is of particular interest to develop alternative natural tools that enable modulation of the associated damaging immune response. With this purpose, we obtained grape seed extract (GSE) from sweet (not fermented) food grade seeds. The aim of our study was to investigate the effect of GSE and its two enriched procyanidins fractions (OPC and PPC) on the inflammatory process and oxidative stress produced by different H. pylori strains in human gastric epithelial cells (AGS). Anti-inflammatory activity was evaluated by measuring the level of interleukin-8 (IL-8) secretion. IL-8 production was significantly reduced in H. pylori-infected human gastric epithelial cells pre-treated with GSE or its enriched fractions when compared with non-pre-treated infected cells (from 21.6% to 87.8%). Pre-treatment with GSE or its fractions significantly decreased intracellular reactive oxygen species (ROS) production in AGS cells after infection, depending on the H. pylori strain. Our results also showed that GSE and its fractions demonstrate antibacterial activity against all strains of H. pylori used in the study. This work demonstrates the effectiveness of GSE enriched in procyanidins against the main events associated with H. pylori infection.

10.
Foods ; 9(10)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993186

RESUMO

Strains of Helicobacter pylori (H. pylori) resistant to various antibiotics have increased in recent years. In this context, the search for new therapeutic approaches is crucial. The aim of the present study was to demonstrate the antibacterial activity of a procyanidin-rich extract obtained from food-grade winery grape seeds against 14 H. pylori strains and elucidate its phenolic composition. Ten strains (71.4%) showed resistance to at least some of the tested antibiotics, while four isolates (28.6%) were susceptible to all antibiotics. Resistance to more than one class of antibiotics was observed in six strains (42.9%). The extract was able to inhibit the growth of all H. pylori strains in a range of a minimum inhibitory concentration (MIC) from 0.015 mg/mL to 0.125 mg/mL, confirming also the existence of a strain-dependent effect. The phenolic composition determined by reverse phase high pressure liquid chromatography, photodiode array, and mass spectrometry detection (RP-HPLC-PAD-MS) analysis revealed the presence of 43 individual compounds and allowed the quantification of 41 of them, including seven procyanidin tetramers, seven procyanidin pentamers, and six galloylated procyanidin dimers, trimers, and tetramers. The extract was composed mainly by catechin and procyanidin oligomers with a total amount of 5.801 mg/100 g, which represent 92% of the total individual phenolic content. Among them, the most abundant were catechins (2.047 mg/100 g), followed by procyanidin dimers (1.550 mg/100 g), trimers (1.176 mg/100 g), tetramers (436 mg/100 g), and pentamers (296 mg/100 g) that represent 35, 27, 20, 8, and 5%, respectively of the total flavanol constituents. The composition profile information may help to improve the production process of useful antibacterial extracts against H. pylori.

11.
Membranes (Basel) ; 10(7)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32660066

RESUMO

The effectiveness of a preparative integrated ultrafiltration/solid-phase extraction (UF/SPE) process for purification of oligomeric procyanidins (OPCs) from a crude grape seed extract (GSE) was studied for the first time. The separation of OPCs from polymeric procyanidins (PPCs) by UF was very efficient. The membrane showed an acceptable filtration flux of 6 to 3.5 L/h·m2 at 0.5 bar of transmembrane pressure and 95% recovery of its water flux after chemical cleaning. The process was scalable to a pilot scale. The separation of very polar and ionic species from OPCs by SPE (XAD7HP and XAD16 resins) was also very good, but both adsorbents lost their retention capacities quickly, due probably to irreversible retention of OPCs/PPCs. Even though the global purification of OPCs by the integrated UF/SPE process allowed the recovery of 24.2 g of highly purified OPCs (83% purity) from 14.4 L of crude grape seed extract, the use of these adsorbents for further purification of the OPCs was very limited.

12.
Microorganisms ; 8(5)2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32443654

RESUMO

In recent years, increased resistance to antibiotics and disinfectants from foodborne bacterial pathogens has become a relevant consumer health issue and a growing concern for food safety authorities [...].

13.
Microorganisms ; 8(1)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952312

RESUMO

The consumption of plums in a fresh form is seasonal, therefore the transformation of plum juice extracts into powdered form is a good alternative for its longer availability throughout the year. The drying process can moderate the physical and chemical properties of the plum extracts, thus, this study examined the changes in biological activity, i.e., antibacterial, antioxidant, and anti-inflammatory properties moderated by freeze, vacuum, and spray drying. It was suggested that the drying processes and the applied parameters might moderate the content of polyphenolic compounds in the powders, which influence the different levels of growth inhibition against the foodborne pathogens (17% to 58% of inhibition), demonstrating a strain-dependent effect. These powders could also induce cellular protection against oxidative stress by preventing intracellular reactive oxygen species (ROS) accumulation (23% to 37% of reduction), but the level of antioxidant capacity may be determined by the conditions applied during the drying process. Moreover, plum extract powders exhibited a greater anti-inflammatory capacity (24% to 39% of inhibition), which would be influenced both, by the type of treatment used and by the temperature used in each treatment. The results demonstrate that the selection of the drying method can be an effective tool for modulating the composition, physical, and bioactive properties of plum extracts powders.

14.
Nutrients ; 11(7)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284490

RESUMO

Fruits and vegetables are pivotal for a healthy diet due partly to their content in bioactive compounds. It is for this reason that we conducted a parallel study to unravel the possible effect on cardiometabolic parameters of the ingestion of anthocyanins, xanthophylls, or both groups of bioactives together in postmenopausal women. Seventy-two postmenopausal women were randomized into an 8-month parallel study: a group consuming 60 mg/day anthocyanins (Group A), a group consuming 6 mg lutein and 2 mg zeaxanthin per day (Group X), and a third group consuming a combination of anthocyanins and xanthophylls in the same amounts (Group A+X). Non-targeted metabolomic analysis was done in plasma samples at baseline and after the 8-month intervention by HPLC-QTOF-MS. Inflammatory, antioxidant, and cardiometabolic parameters were measured at the beginning of the study and after 4 and 8-months intervention. Compared with baseline values, none of the 8-month treatments significantly (p < 0.05) changed systolic or diastolic blood pressure (BP), plasma C-reactive protein, interleukin 6, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, monocyte chemoattractant protein-1 or matrix metalloproteinases 2 and 9. Only plasma glucose levels were significantly decreased by treatment A+X after 8 months, and the plasma metabolomic profile was clearly affected by all three dietary supplementations after 8 months. In parallel, there was an increase, also for the three groups, in the plasma ferric reducing antioxidant power value that did not show any synergistic effect between the two groups of bioactives. Postmenopausal women could benefit from an increase in anthocyanins and xanthophylls intake, through the consumption of fruits and vegetables rich in these two types of compounds. Accordingly, plasma glucose and, above all, the reducing power in plasma, could be improved.


Assuntos
Antocianinas/administração & dosagem , Antioxidantes/administração & dosagem , Glicemia/efeitos dos fármacos , Suplementos Nutricionais , Estresse Oxidativo/efeitos dos fármacos , Pós-Menopausa , Xantofilas/administração & dosagem , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Metabolômica/métodos , Pessoa de Meia-Idade , Oxirredução , Espanha , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo , Resultado do Tratamento
15.
Nutrients ; 10(8)2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-30044439

RESUMO

Xanthophylls (lutein, L; zeaxanthin, Z) and anthocyanins are often included in food supplements to improve ocular health. There are no dietary reference intakes for them. The aim was to assess the effects of L, Z and anthocyanin supplementation on short and long-term lutein status markers (serum concentration and macular pigment optical density (MPOD)). Seventy-two postmenopausal women were randomized into a parallel study of 8 months: Group A-anthocyanines (60 mg/day); Group X-xanthophylls (6 mg L + 2 mg Z/day); Group X+A-anthocyanines (60 mg/day) + xanthophylls (6 mg L + 2 mg Z/day). At the beginning of the study, 4 and 8 month serum L and Z concentrations were determined (HPLC), as well as L, Z and anthocyanine dietary intake and MPOD (heterochromic flicker photometry). Baseline concentrations of L (0.35 ± 0.19 µmol/L), Z (0.11 ± 0.05 µmol/L), L+Z/cholesterol/triglycerides (0.07 ± 0.04 µmol/mmol) increased in Group X (2.8- and 1.6-fold in L and Z concentrations) and in group XA (2- and 1.4-fold in L and Z concentrations). MPOD (baseline: 0.32 ± 0.13 du) was not modified in any of the groups at the end of the study. There were no differences in the dietary intake of L+Z and anthocyanin at any point in time in any group. Supplementation of L and Z at a dietary level provoked an increase in their serum concentration that was not modified by simultaneous supplementation with anthocyanins.


Assuntos
Antocianinas/farmacologia , Luteína/sangue , Pigmento Macular/fisiologia , Pós-Menopausa , Xantofilas/farmacologia , Zeaxantinas/sangue , Idoso , Antocianinas/administração & dosagem , Suplementos Nutricionais , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Xantofilas/administração & dosagem
16.
Food Chem ; 257: 341-349, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622220

RESUMO

Legumes offer the possibility to develop multifunctional foods with benefits for metabolic syndrome. Our objective was to study the effect of alkaline fermentation by Lactobacillus plantarum and Savinase (FLPS) as well the individual effects of both processes on peptides, phenolics and bioactivity of lentil. FLPS increased peptides and some flavonoids and enhanced antioxidant activity, inhibition of angiotensin I-converting enzyme (ACE) and intestinal maltase activities of lentil soluble fraction. Savinase contributed to peptide release, ACE inhibitory and antioxidant activities of lentil soluble fraction. L. plantarum affected to phenolic composition, α-glucosidase and lipase inhibitory activities. Mass spectrometry analysis of the most active fermented lentil subfraction allowed the identification of the main bioactive compounds. Gastrointestinal digestion of fermented lentil increased bioaccessibility of peptides and phenolics as well as antioxidant activity. FLPS enhanced the overall healthy potential of lentil offering the possibility of its use as strategy for lentil functionalization.


Assuntos
Reatores Biológicos , Lactobacillus plantarum/metabolismo , Lens (Planta)/metabolismo , Serina Endopeptidases/metabolismo , Animais , Cromatografia em Gel , Flavonoides/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lens (Planta)/química , Camundongos , Peptídeos/química , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/metabolismo , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
17.
Food Chem ; 248: 262-271, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29329853

RESUMO

Lentil fermentation has a promising potential as a strategy for development of multifunctional ingredients targeting metabolic syndrome (MetS). Response surface methodology was applied to optimize lentil fermentation and study its effects on generation of peptides, soluble phenolics and bioactivities. Fermentation using Lactobacillus plantarum and Savinase® 16 L was carried out at different pH (6.5-8.5) and times (5.5-30 h). Analysis of variance was performed to evaluate linear, quadratic and interaction effects between fermentation parameters. pH positively affected peptides, soluble phenolic compounds and antioxidant activity whereas a negative impact on lipase inhibitory activity was observed (p < .0001). Time showed positive effect on proteolysis and negatively affected angiotensin I-converting enzyme inhibitory activity of fermented lentil (p < .0001). Multivariate optimization led to high levels of peptides, soluble phenolics and bioactivity of fermented lentil at pH 8.5 and 11.6 h. In conclusion, this study might contribute to the development of functional ingredients from lentil for MetS management.


Assuntos
Antioxidantes/farmacologia , Lens (Planta)/metabolismo , Lens (Planta)/microbiologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Antioxidantes/metabolismo , Fermentação , Alimentos Fermentados , Inibidores de Glicosídeo Hidrolases/farmacologia , Concentração de Íons de Hidrogênio , Lactobacillus plantarum/metabolismo , Lens (Planta)/química , Lipase/antagonistas & inibidores , Camundongos , Fenóis/metabolismo , Proteínas de Vegetais Comestíveis/metabolismo , Proteólise , Células RAW 264.7
18.
Food Chem ; 242: 75-82, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29037738

RESUMO

The aim was to investigate the potential of germinated soybean proteins asa source of peptides with anticancer and anti-inflammatory activities produced after simulated gastrointestinal digestion. Protein concentrate from germinated soybean was hydrolysed with pepsin/pancreatin and fractionated by ultrafiltration. Whole digest and fractions>10, 5-10, and<5kDa caused cytotoxicity to Caco-2, HT-29, HCT-116 human colon cancer cells, and reduced inflammatory response caused by lipopolysaccharide in macrophages RAW 264.7. Antiproliferative and anti-inflammatory effects were generally higher in 5-10kDa fractions. This fraction was further purified by semi-preparative chromatography and characterised by HPLC-MS/MS. The most potent fraction was mainly composed of ß-conglycinin and glycinin fragments rich in glutamine. This is the first report on the anti-cancer and anti-inflammatory effects of newly isolated and identified peptides from germinated soybean released during gastrointestinal digestion. These findings highlight the potential of germination as a process to obtain functional foods or nutraceuticals for colon cancer prevention.


Assuntos
Neoplasias do Colo/metabolismo , Glycine max/metabolismo , Peptídeos/metabolismo , Proteínas de Soja/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Proliferação de Células , Cromatografia Líquida de Alta Pressão , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Neoplasias do Colo/fisiopatologia , Digestão , Germinação/efeitos dos fármacos , Humanos , Hidrólise , Camundongos , Pancreatina/química , Pancreatina/metabolismo , Pepsina A/química , Pepsina A/metabolismo , Peptídeos/química , Células RAW 264.7 , Proteínas de Soja/química , Glycine max/química , Glycine max/crescimento & desenvolvimento , Espectrometria de Massas em Tandem
19.
Environ Sci Pollut Res Int ; 24(6): 5746-5756, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28050761

RESUMO

This work aims to investigate the nature and the specific mechanisms by which polycarboxylic compounds participate in the tolerance of Silene vulgaris to Cr with special attention given to the rhizosphere system. This knowledge is important to use this species in the implementation of phytoremediation technologies in Cr-polluted soils. According to the results, chromium is chelated and mobilized by the citric and malic acids in plant tissues, while oxalic acid might participate in the reduction and chelation of Cr in the rhizosphere. At the applied doses, the response of both exudation rate and root exudate composition (total polyphenols and quercitin) seems to involve a rearrangement in the lignification of the plant cell wall to immobilize Cr. Quercetin-3-dirhamnosyl-galactoside and apiin (apigenin-7-O-apiosyl-glucoside) have been identified as the major polyphenols in the root exudates of S. vulgaris. The increments found in the apiin concentration in root exudates seem to be related to the protection against Cr toxicity by chelation of Cr or by free radical scavenging. Though earlier response is detected in plant tissues, results from this work together with previous studies in S. vulgaris indicate that exudation might be a regulated mechanism of protection under Cr exposition in S. vulgaris that may involve mainly Cr reduction and chelation.


Assuntos
Biodegradação Ambiental , Cromo , Silene , Ácido Cítrico , Malatos , Ácido Oxálico , Raízes de Plantas
20.
Food Funct ; 7(2): 1067-76, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26781209

RESUMO

Increased exposure to solar ultraviolet B (UVB) radiation causes oxidative damage that may promote age related macular degeneration (AMD) and other ocular pathologies. This study is aimed to demonstrate the protective effects of some anthocyanins and xanthophylls against the UVB-induced oxidative damage to retinal pigment epithelial (RPE) cells. ARPE-19 cells were treated with 5 µM cyanidin-3-O-glucoside, delphinidin-3-O-glucoside, lutein, zeaxanthin or a mixture of cyanidin-3-O-glucoside:zeaxanthin prior to UVB exposure (500 J m(-2)). Cell viability and mitogen-activated protein kinase (MAPK) phosphorylation were determined by MTT assay and western blot analysis, respectively. Oxidative damage was evaluated by measuring the intracellular reactive oxygen species (ROS). The data showed that UVB irradiation reduces the cell viability to 46% with increasing of intracellular ROS levels and phosphorylation of MAPKs. However, pre-treatment (60 min) with 5 µM cyanidin-3-O-glucoside, lutein or zeaxanthin significantly reduced cellular ROS levels and phosphorylation of MAPKs (JNK1/2 and p38) mediated by UVB irradiation and subsequently increased cell viability. Thus, results show that UVB irradiation is able to induce apoptosis in ARPE-19 cells through oxidative stress; however anthocyanins and xanthophylls pre-treatment can attenuate this damage. This suggests that cyanidin-3-O-glucoside, lutein and zeaxanthin are effective in preventing UVB-induced damage in RPE cells and may be suitable as chemoprotective factors for the prevention of ocular damage. The use of natural dietary antioxidants might reduce ocular oxidative damage caused by UVB radiation.


Assuntos
Antocianinas/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/efeitos da radiação , Epitélio Pigmentado da Retina/citologia , Raios Ultravioleta/efeitos adversos , Xantofilas/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Olho/citologia , Olho/efeitos dos fármacos , Olho/efeitos da radiação , Glucosídeos/farmacologia , Humanos , Luteína/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Zeaxantinas/farmacologia
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