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1.
Anal Bioanal Chem ; 415(13): 2613-2627, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36631573

RESUMO

Microbial metabolomics allows understanding and to comprehensively analyse metabolites, and their related cellular and metabolic processes, that are produced and released to the extracellular environment under specific conditions. In that regard, the main objective of this research is to understand the impact of culture media changes in the metabolic profile of Pedobacter lusitanus NL19 (NL19) and Pedobacter himalayensis MTCC 6384 (MTCC6384) and respective influence on the production of biotechnologically relevant compounds. Solid-phase microextraction combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry with time-of-flight analyser (GC × GC-ToFMS) was applied to comprehensively study the metabolites produced by NL19 and MTCC6384 both in tryptic soy broth 100% (TSB100) and tryptic soy broth with 25% casein peptone (PC25). A total of 320 metabolites were putatively identified, which belong to different chemical families: alcohols, aldehydes, esters, ethers, hydrocarbons, ketones, nitrogen compounds, sulphur compounds, monoterpenes, and sesquiterpenes. Metabolites that were statistically different from the control (sterile medium) were selected allowing for the construction of the metabolic profile of both strains. A set of 80 metabolites was tentatively associated to the metabolic pathways such as the metabolism of fatty acids, branched-chain aminoacids, phenylalanine, methionine, aromatic compounds, and monoterpene and sesquiterpene biosynthesis. This study allowed to better understand how slight changes of the culture media and thus the composition of nutrients impair the metabolic profile of bacteria, which may be further explored for metabolomics pipeline construction or biotechnological applications.


Assuntos
Aldeídos , Compostos Orgânicos Voláteis , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas , Monoterpenos , Meios de Cultura , Compostos Orgânicos Voláteis/química , Microextração em Fase Sólida/métodos
2.
Molecules ; 27(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36014506

RESUMO

Chromatography was born approximately one century ago and has undergone outstanding technological improvements in innovation, research, and development since then that has made it fundamental to advances in knowledge at different levels, with a relevant impact on the well-being and health of individuals. Chromatography boosted a comprehensive and deeper understanding of the complexity and diversity of human-environment interactions and systems, how these interactions affect our life, and the several societal challenges we are currently facing, namely those related to the sustainability of our planet and the future generations. From the life sciences, which allowed us to identify endogenous metabolites relevant to disease mechanisms, to the OMICS field, nanotechnology, clinical and forensic analysis, drug discovery, environment, and "foodprint", among others, the wide range of applications of today's chromatographic techniques is impressive. This is fueled by a great variability of powerful chromatographic instruments currently available, with very high sensitivity, resolution, and identification capacity, that provide a strong basis for an analytical platform able to support the challenging demands of the postgenomic and post COVID-19 eras. Within this context, this review aims to address the great utility of chromatography in helping to cope with several societal-based challenges, such as the characterization of disease and/or physiological status, and the response to current agri-food industry challenges of food safety and sustainability, or the monitoring of environmental contamination. These are increasingly important challenges considering the climate changes, the tons of food waste produced every day, and the exponential growth of the human population. In this context, the principles governing the separation mechanisms in chromatography as well the different types and chromatographic techniques will be described. In addition, the major achievements and the most important technological advances will be also highlighted. Finally, a set of studies was selected in order to evince the importance of different chromatographic analyses to understand processes or create fundamental information in the response to current societal challenges.


Assuntos
COVID-19 , Eliminação de Resíduos , Cromatografia , Poluição Ambiental , Alimentos , Humanos
3.
Molecules ; 27(9)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35566076

RESUMO

Broa is a Portuguese maize bread with characteristic sensory attributes that can only be achieved using traditional maize varieties. This study intends to disclose the volatile compounds that are mainly associated with the baking process of broas, which can be important contributors to their aroma. Twelve broas were prepared from twelve maize flours (eleven traditional maize varieties and one commercial hybrid). Their volatile compounds were analyzed by GC×GC-ToFMS (two-dimensional gas chromatography coupled with time-of-flight mass spectrometry) for an untargeted screening of the chemical compounds mainly formed during baking. It was possible to identify 128 volatiles that belonged to the main chemical families formed during this stage. Among these, only 16 had been previously detected in broas. The most abundant were furans, furanones, and pyranones, but the most relevant for the aroma of broas were ascribed to sulfur-containing compounds, in particular dimethyl trisulfide and methanethiol. Pyrazines might contribute negatively to the aroma of broas since they were present in higher amounts in the commercial broa. This work constitutes the most detailed study of the characterization of broas volatile compounds, particularly those formed during the Maillard reaction. These findings may contribute to the characterization of other maize-based foodstuffs, ultimately improving the production of foods with better sensory features.


Assuntos
Compostos Orgânicos Voláteis , Pão/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Odorantes/análise , Compostos de Enxofre/análise , Compostos Orgânicos Voláteis/análise , Zea mays/química
4.
Allergy ; 75(7): 1630-1639, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31997360

RESUMO

BACKGROUND: Analyses of exhaled volatile organic compounds (VOCs) have shown promising results when distinguishing individuals with asthma. Currently, there are no biomarkers for uncontrolled asthma. Therefore, we aimed to assess, in a real-life clinical setting, the ability of the exhaled VOC analysis, using an electronic nose (eNose), to identify individuals with uncontrolled asthma. METHODS: A cross-sectional study was conducted, and breath samples from 199 participants (130 females, aged 6-78, 66% with asthma) were analysed using an eNose. A multivariate unsupervised cluster analysis, using the resistance data from 32 sensors, could distinguish three clusters of VOC patterns in the training and testing groups. Comparisons between the clusters were performed using the one-way ANOVA, Kruskal-Wallis and chi-squared tests. RESULTS: In the training set (n = 121), three different clusters covering asthma, lung function, symptoms in the previous 4 weeks and age were identified. The pairwise comparisons showed significant differences with respect to chest tightness during exercise, dyspnoea and gender. These findings were confirmed in the testing set (n = 78) where the training model identified three clusters. The participants who reported fewer respiratory symptoms (dyspnoea and night-time awakenings) were grouped into one cluster, while the others comprised participants who showed similar poor control over symptoms with the distribution of the individuals with asthma being significantly different between them. CONCLUSIONS: In a clinical setting, the analysis of the exhaled VOC profiles using an eNose could be used as a fast and noninvasive complementary assessment tool for the detection of uncontrolled asthma symptoms.


Assuntos
Asma , Compostos Orgânicos Voláteis , Adolescente , Adulto , Idoso , Asma/diagnóstico , Asma/epidemiologia , Testes Respiratórios , Criança , Estudos Transversais , Nariz Eletrônico , Expiração , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
5.
Molecules ; 25(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936556

RESUMO

Wine aroma is the result of complex interactions between volatile compounds and non-volatile ones and individual perception phenomenon. In this work, an aroma network approach, that links volatile composition (chromatographic data) with its corresponding aroma descriptors was used to explain the wine aroma properties. This concept was applied to six monovarietal wines from Bairrada Appellation (Portugal) and used as a case study. A comprehensive determination of the wines' volatile composition was done (71 variables, i.e., volatile components), establishing a workflow that combines extraction techniques and gas chromatographic analysis. Then, a bipartite network-based approach consisting of two different nodes was built, one with 19 aroma descriptors, and the other with the corresponding volatile compound(s). To construct the aroma networks, the odor active values were calculated for each determined compound and combined with the bipartite network. Finally, the aroma network of each wine was compared with sensory descriptive analysis. The analysis of the specific aroma network of each wine revealed that Sauvignon Blanc and Arinto white wines present higher fruity (esters) and sweet notes (esters and C13 norisoprenoids) than Bical wine. Sauvignon Blanc also exhibits higher toasted aromas (thiols) while Arinto and Bical wines exhibit higher flowery (C13 norisoprenoids) and herbaceous notes (thiols), respectively. For red wines, sweet fruit aromas are the most abundant, especially for Touriga Nacional. Castelão and Touriga Nacional wines also present toasted aromas (thiols). Baga and Castelão wines also exhibit fusel/alcohol notes (alcohols). The proposed approach establishes a chemical aroma fingerprint (aroma ID) for each type of wine, which may be further used to estimate wine aroma characteristics by projection of the volatile composition on the aroma network.


Assuntos
Odorantes/análise , Vitis/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Cromatografia Gasosa , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Norisoprenoides/química , Norisoprenoides/isolamento & purificação , Portugal , Compostos de Sulfidrila/química , Compostos de Sulfidrila/isolamento & purificação , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação
6.
Mar Drugs ; 17(10)2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31569367

RESUMO

Marine resources are considered as a very promising source of bioactive molecules, and macroalgae in particular have gained special attention, due to their structurally diverse composition. Particular interest has been devoted to the brown macroalga Bifurcaria bifurcata, due to their abundance in bioactive linear diterpenes. In this appraisal, a thorough review concerning the methodologies used in the extraction, fractionation, and identification of diterpenes from B. bifurcata is provided and discussed in detail. An exhaustive compilation of the mass spectra and nuclear magnetic resonance (NMR) data are also provided. The in vitro and in chemico assays already performed to assess different biological activities attributed to B. bifurcata diterpenes are also reviewed, emphasizing the use of isolated components, enriched fractions, or crude extracts. The associated major strengths and challenges for the exploitation of B. bifurcata diterpenes for high-value applications are critically discussed.


Assuntos
Diterpenos/farmacologia , Phaeophyceae/química , Extratos Vegetais/isolamento & purificação , Alga Marinha/química , Anti-Infecciosos/isolamento & purificação , Antioxidantes/isolamento & purificação , Diterpenos/isolamento & purificação , Química Verde/métodos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
7.
Ecotoxicol Environ Saf ; 186: 109759, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31606646

RESUMO

Rhizobia have a significant agronomic and environmental role and are eminent contributors to soil fertility. However, this group of microorganisms are affected by various environmental stresses, such as Cd contamination. High Cd concentrations change bacterial metabolism. During this metabolic shift, bacteria alter their volatilome (the set of volatile metabolites synthesized by an organism). In the presence of Cd, peak areas of saturated aldehydes and alcohols were previously reported to increase, and the consequences of this increase to cells are poorly known. In this study, Rhizobium sp. strain E20-8 cells were exposed to Cd and aldehydes or their conjugated alcohols. Exposure to Cd (100 µM) inhibited cell growth and induced several biomarkers of oxidative stress. The present study also evidenced the higher toxicity of most aldehydes relatively to the corresponding alcohol in the presence of Cd, suggesting that reduction of aldehydes into alcohols may be an effective mechanism to restrain aldehydes toxicity in Rhizobium cells under Cd toxicity. Nonetheless, the protective effect was dependent on the pair aldehyde-respective alcohol considered and it differed between Cd stressed and non-stressed cells. Differences in the ability to convert aldehydes to alcohols may emerge as a new feature helping explain the oxidative tolerance variability among bacteria.


Assuntos
Álcoois/química , Aldeídos/química , Cádmio/toxicidade , Rhizobium/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Tolerância a Medicamentos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução , Rhizobium/crescimento & desenvolvimento , Rhizobium/metabolismo , Solo/química
8.
Int J Mol Sci ; 20(4)2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795544

RESUMO

Worldwide, foodborne diseases are a growing public health problem. Among the infectious bacteria, non-typhoidal Salmonella enterica serovars (NTS) are the major cause of hospitalization and death, and the emergence and spread of their antibiotic-resistance is becoming a worldwide health issue. This, coupled with the restrictions of antibiotics use in agriculture and animal production, calls for alternative approaches to solve this problem. Plant-derived aqueous extracts compounds could provide novel straightforward approaches to control pathogenic bacteria. This review discusses the antimicrobial activity of aqueous plant extracts against Salmonella serovars, the possible mechanisms of action involved, which components/structures might be responsible for such activity, and the current challenges for the use of these extracts/components in Salmonella infection management and their application perspectives.


Assuntos
Antibacterianos/uso terapêutico , Extratos Vegetais/uso terapêutico , Infecções por Salmonella/tratamento farmacológico , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Salmonella enterica/efeitos dos fármacos
9.
Int J Mol Sci ; 20(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480214

RESUMO

Substantial amounts of vine wastes are produced during vineyard management, and the chemical profiling of high-value lipophilic phytochemicals is becoming crucial in order to find a complementary route towards their integrated valorisation. The prospection of bioactive phytochemicals from unripe grape, vine shoot, vine cane, stalk and leaf dichloromethane extracts was carried out by gas chromatography-mass spectrometry (GC-MS), analysing samples from a mixture of four red Vitis vinifera L. varieties (Baga, Aragonez, Água Santa and Shiraz), collected at Bairrada Appellation, as a representative case study of typical multi-variety Portuguese vineyards. Vine wastes showed distinct amounts of lipophilic extract, ranging from 0.68% (vine canes) to 13.35% (vine leaves) at dry weight (dw). Thirty-three components were identified, including fatty acids and alcohols, sterols and triterpenoids accounting for amounts from 118.9 mg/100 g dw to 1512.0 mg/100 g dw. The integrated study revealed that unripe grape, stalk and leaf dichloromethane extracts stood out as possible sources of triterpenic compounds (103.2 to 653.5 mg/100 g dw), with lupeol, ursolic and oleanolic acids prevailing. Leaf extract is also reported as an undervalued source of α-tocopherol, as the major component detected in this matrix (300.5 mg/100 g dw). These exploratory results are a relevant contribution for the exploitation of undervalued vine residues as a source of health-promoting components with the potential to be used as supplements or nutraceutical ingredients.


Assuntos
Lipídeos/química , Compostos Fitoquímicos/farmacologia , Vitis/química , Resíduos/análise , Álcoois/análise , Ácidos Graxos/análise , Extratos Vegetais/química , Esteróis/análise , Triterpenos/análise
10.
Curr Opin Pulm Med ; 24(1): 94-103, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29059088

RESUMO

PURPOSE OF REVIEW: Metabolomics has been used to uncover the metabolic signatures of asthma, both for biomarker identification and pathophysiologic mechanisms research. We aimed to review recent advances in this field, published since 2016, and discuss these findings implications to future research and application into clinical practice. RECENT FINDINGS: Experimental asthma models and clinical studies in both children and adults supported independent metabolic signatures of asthma. Common reported pathways included purine, glycerophospholipid, glutathione, fatty acids, and arginine and proline metabolism. Metabolomics-based studies identified candidate biomarkers related to asthma severity and corticosteroid resistance, and supported the definition of the obesity-related phenotype at the molecular level. A systematic review with meta-analysis and recent prospective studies favored exhaled volatile organic compounds as one of the most promising biomarkers in asthma diagnosis and monitoring. SUMMARY: Metabolomics has provided unique and novel insights into asthma profiling at the molecular level. Current challenges include procedures standardization and control of potentially confounding variables for external validation. Point-of-care technology developments bring metabolomics closer to clinical practice. In addition to biomarkers identification, relating metabolites to their biologic role will serve as critical foundations for understanding the biology underpinning asthma heterogeneity and for specific-targeted therapies. VIDEO ABSTRACT.


Assuntos
Corticosteroides/metabolismo , Asma/metabolismo , Metabolômica , Obesidade/metabolismo , Purinas/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Asma/fisiopatologia , Biomarcadores/metabolismo , Expiração , Humanos , Metabolômica/tendências , Obesidade/fisiopatologia , Fenótipo , Valor Preditivo dos Testes
11.
Pediatr Allergy Immunol ; 28(5): 452-457, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28452071

RESUMO

We hypothesize that oxidative stress induced by trichloramine exposure during swimming could be related to etiopathogenesis of asthma among elite swimmers. AIM: To investigate the effect of a swimming training session on oxidative stress markers of asthmatic compared to non-asthmatic elite swimmers using exhaled breath (EB) metabolomics. METHODS: Elite swimmers annually screened in our department (n=27) were invited and those who agreed to participate (n=20, of which 9 with asthma) had EB collected (Tedlar® bags) before and after a swimming training session. SPME fiber (DVB/CAR/PDMS) was used to extract EB metabolites followed by a multidimensional gas chromatography analysis (GC×GC-ToFMS). Dataset comprises eight metabolites end products of lipid peroxidation: five aliphatic alkanes (nonane, 2,2,4,6,6-pentamethylheptane, decane, dodecane, and tetradecane) and three aldehydes (nonanal, decanal, and dodecanal). To assess exercise impact on lipid peroxidation markers, data were analyzed using principle component analysis (PCA), which was run on the original data set and on the data set constructed using differences in the metabolite total areas before and after exercise session. RESULTS: Heatmap representation revealed that metabolites content decreased after exercise, both for control and asthma groups; however, the greater decrease was observed for controls. Asthmatics and controls did not form separated clusters; however, control swimmers demonstrated a more varied response to the exercise being dispersed along all score plot. CONCLUSION: In well-trained athletes, swimming is associated with a decrease in oxidative stress markers independently of the presence of asthma, although a more pronounced decrease was seen in controls.


Assuntos
Asma/induzido quimicamente , Cloretos/toxicidade , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Compostos de Nitrogênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Natação , Adolescente , Asma/metabolismo , Biomarcadores/metabolismo , Testes Respiratórios , Estudos de Casos e Controles , Cromatografia Gasosa , Expiração , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Estudos Retrospectivos
12.
J Sep Sci ; 40(10): 2228-2237, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28345797

RESUMO

Saccharomyces spp. are widely used in the food and beverages industries. Their cellular excreted metabolites are important for general quality of products and can contribute to product differentiation. This exploratory study presents a metabolomics strategy for the comprehensive mapping of cellular metabolites of two yeast species, Saccharomyces cerevisiae and S. pastorianus (both collected in an industrial context) through a multidimensional chromatography platform. Solid-phase microextraction was used as a sample preparation method. The yeast viability, a specific technological quality parameter, was also assessed. This untargeted analysis allowed the putative identification of 525 analytes, distributed over 14 chemical families, the origin of which may be explained through the pathways network associated with yeasts metabolism. The expression of the different metabolic pathways was similar for both species, event that seems to be yeast genus dependent. Nevertheless, these species showed different growth rates, which led to statistically different metabolites content. This was the first in-depth approach that characterizes the headspace content of S. cerevisiae and S. pastorianus species cultures. The combination of a sample preparation method capable of providing released volatile metabolites directly from yeast culture headspace with comprehensive two-dimensional gas chromatography was successful in uncovering a specific metabolomic pattern for each species.


Assuntos
Indústria Alimentícia , Metabolômica , Saccharomyces cerevisiae/metabolismo , Saccharomyces/metabolismo , Cromatografia Gasosa , Microextração em Fase Sólida
13.
Curr Microbiol ; 74(5): 575-583, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28260118

RESUMO

The aim of this study is to evaluate the effects of the inoculation of the saltmarsh plant (Halimione portulacoides) with Pseudomonas sp. SPN31 nah+ combined with exposure to 2-methylnaphthalene (2-MtN) on the plant rhizosphere and endosphere bacterial communities as well as on plant health. To achieve this goal, microcosm experiments were set up. Denaturing gradient gel electrophoresis (DGGE) profiles and statistical analysis showed that rhizosphere and endosphere bacterial communities had distinct responses to plant inoculation and/or exposure to 2-MtN. PCR-sequencing analysis of nah genes encoding for 2-MtN degrading enzymes suggested the presence of Pseudomonas sp. SPN31 nah+ in the endosphere of H. portulacoides with 2-MtN contamination. Moreover, a significant effect in the photosynthetic performance of inoculated plants was detected. To conclude, despite the potential beneficial effect of plant inoculation with Pseudomonas sp. SPN31 nah+ endophytic bacteria may have on plant health, no significant effect on the removal of MtN was detected for the level of contamination used in the study.


Assuntos
Bactérias , Chenopodiaceae/efeitos dos fármacos , Chenopodiaceae/microbiologia , Naftalenos/efeitos adversos , Pseudomonas/fisiologia , Rizosfera , Poluentes do Solo/efeitos adversos , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Chenopodiaceae/fisiologia , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Genes Bacterianos , Naftalenos/metabolismo , Fotossíntese , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Microbiologia do Solo , Poluentes do Solo/metabolismo , Compostos Orgânicos Voláteis
14.
Mar Drugs ; 15(11)2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29104253

RESUMO

Macroalgae have been seen as an alternative source of molecules with promising bioactivities to use in the prevention and treatment of current lifestyle diseases. In this vein, the lipophilic fraction of short-term (three weeks) cultivated Bifurcaria bifurcata was characterized in detail by gas chromatography-mass spectrometry (GC-MS). B. bifurcata dichloromethane extract was composed mainly by diterpenes (1892.78 ± 133.97 mg kg-1 dry weight (DW)), followed by fatty acids, both saturated (550.35 ± 15.67 mg kg-1 DW) and unsaturated (397.06 ± 18.44 mg kg-1 DW). Considerable amounts of sterols, namely fucosterol (317.68 ± 26.11 mg kg-1 DW) were also found. In vitro tests demonstrated that the B. bifurcata lipophilic extract show antioxidant, anti-inflammatory and antibacterial activities (against both Gram-positive and Gram-negative bacteria), using low extract concentrations (in the order of µg mL-1). Enhancement of antibiotic activity of drug families of major clinical importance was observed by the use of B. bifurcata extract. This enhancement of antibiotic activity depends on the microbial strain and on the antibiotic. This work represents the first detailed phytochemical study of the lipophilic extract of B. bifurcata and is, therefore, an important contribution for the valorization of B. bifurcata macroalgae, with promising applications in functional foods, nutraceutical, cosmetic and biomedical fields.


Assuntos
Antibacterianos/farmacologia , Organismos Aquáticos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alga Marinha , Animais , Antibacterianos/química , Lipídeos/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
15.
Int J Mol Sci ; 18(1)2016 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-28025494

RESUMO

Elderberry (Sambucus nigra L.) lipophilic and polar extract dietary supplementation effects were evaluated according to diabetes management indices, using an in vivo model. A research pipeline was constructed, that ranged from extract preparation, partial chemical characterization and toxicity evaluation, to examining the elderberry extract dietary supplementation effects on biofluid and tissues. Extracts toxicity was screened using an Aliivibrio fischeri bioluminescence model. A concentration of up to 60 mg/L was selected, and rat doses for oral supplementation were computed applying the interspecies correlation between A. fischeri and rats. Wistar type 2 diabetic rats, induced by streptozotocin (STZ), were fed a high-fat diet and supplemented for 4 weeks at doses of 190 and 350 mg/kg body weight/day of lipophilic and polar extract, respectively. As far as we know, lipophilic elderberry extract supplementation was assessed for the first time, while polar extract was administrated at higher doses and for a shorter period compared to previous studies, aiming to evaluate subacute supplementation effects. The polar extract modulated glucose metabolism by correcting hyperglycemia, while the lipophilic extract lowered insulin secretion. Both extracts lowered insulin resistance, without remarkable alterations to hematological indices, sera lipids and sera and tissular trace element homeostasis. In conclusion, elderberries are a potential source of bioactive compounds for formulations to be used as co-adjuvants in diabetes management.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Sambucus nigra/química , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/etiologia , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Resistência à Insulina , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Wistar , Estreptozocina/toxicidade
16.
Glob Chang Biol ; 21(5): 1871-86, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25382269

RESUMO

There is growing concern that modifications to the global environment such as ocean acidification and increased ultraviolet radiation may interact with anthropogenic pollutants to adversely affect the future marine environment. Despite this, little is known about the nature of the potential risks posed by such interactions. Here, we performed a multifactorial microcosm experiment to assess the impact of ocean acidification, ultraviolet B (UV-B) radiation and oil hydrocarbon contamination on sediment chemistry, the microbial community (composition and function) and biochemical marker response of selected indicator species. We found that increased ocean acidification and oil contamination in the absence of UV-B will significantly alter bacterial composition by, among other things, greatly reducing the relative abundance of Desulfobacterales, known to be important oil hydrocarbon degraders. Along with changes in bacterial composition, we identified concomitant shifts in the composition of oil hydrocarbons in the sediment and an increase in oxidative stress effects on our indicator species. Interestingly, our study identifies UV-B as a critical component in the interaction between these factors, as its presence alleviates harmful effects caused by the combination of reduced pH and oil pollution. The model system used here shows that the interactive effect of reduced pH and oil contamination can adversely affect the structure and functioning of sediment benthic communities, with the potential to exacerbate the toxicity of oil hydrocarbons in marine ecosystems.


Assuntos
Mudança Climática , Estuários , Sedimentos Geológicos/microbiologia , Microbiota/fisiologia , Modelos Biológicos , Poluição por Petróleo/efeitos adversos , Sequência de Bases , Primers do DNA/genética , Deltaproteobacteria/metabolismo , Deltaproteobacteria/efeitos da radiação , Hidrocarbonetos/análise , Concentração de Íons de Hidrogênio , Microbiota/efeitos dos fármacos , Dados de Sequência Molecular , Portugal , Análise de Sequência de DNA , Raios Ultravioleta
17.
J Sep Sci ; 38(12): 2140-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25907307

RESUMO

The aroma profile of beer is crucial for its quality and consumer acceptance, which is modu-lated by a network of variables. The main goal of this study was to optimize solid-phase microextraction experimental parameters (fiber coating, extraction temperature, and time), taking advantage of the comprehensive two-dimensional gas chromatography structured separation. As far as we know, it is the first time that this approach was used to the untargeted and comprehensive study of the beer volatile profile. Decarbonation is a critical sample preparation step, and two conditions were tested: static and under ultrasonic treatment, and the static condition was selected. Considering the conditions that promoted the highest extraction efficiency, the following parameters were selected: poly(dimethylsiloxane)/divinylbenzene fiber coating, at 40ºC, using 10 min of pre-equilibrium followed by 30 min of extraction. Around 700-800 compounds per sample were detected, corresponding to the beer volatile profile. An exploratory application was performed with commercial beers, using a set of 32 compounds with reported impact on beer aroma, in which different patterns can be observed through the structured chromatogram. In summary, the obtained results emphasize the potential of this methodology to allow an in-depth study of volatile molecular composition of beer.

18.
Food Microbiol ; 46: 515-520, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25475323

RESUMO

In this work, the development of resistance and the recovery of growth after several consecutive cycles of high hydrostatic pressure (HPP) were for the first time evaluated in different strains of Staphylococcus aureus. Three strains of this important and highly resilient to HPP foodborne pathogen were used: a non-enterotoxigenic ATCC 6538 strain, treated with 600 MPa for 30 min at 20 °C, and the toxigenic strains 2153 MA (with enterotoxin A) and 2065 MA (with the enterotoxins A, G and I), treated with 600 MPa for 15 min at 20 °C. After the first treatment, surviving colonies were used to produce new bacterial cultures. This procedure was repeated nine times more for each bacterium or until total inactivation occurred. The inactivation profile of non-enterotoxic strain and the two enterotoxic strains did not change after consecutive cycles, but the toxic strain with three enterotoxins was completely inactivated after the fourth cycle. The three strains did not recover their viability after 14 days. The results indicate that HPP effectively inactivates non-toxigenic and toxigenic strains of S. aureus after a single treatment. The surviving bacteria did not develop resistance after 10 cycles of pressurization and did not recover their viability after 14 days of incubation.


Assuntos
Pressão Hidrostática , Staphylococcus aureus/química , Staphylococcus aureus/crescimento & desenvolvimento , Enterotoxinas/metabolismo , Microbiologia de Alimentos , Viabilidade Microbiana , Staphylococcus aureus/classificação , Staphylococcus aureus/metabolismo
19.
Int J Mol Sci ; 16(6): 14194-209, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26110390

RESUMO

The lipophilic composition of wild Arbutus unedo L. berries, collected from six locations in Penacova (center of Portugal), as well as some general chemical parameters, namely total soluble solids, pH, titratable acidity, total phenolic content and antioxidant activity was studied in detail to better understand its potential as a source of bioactive compounds. The chemical composition of the lipophilic extracts, focused on the fatty acids, triterpenoids, sterols, long chain aliphatic alcohols and tocopherols, was investigated by gas chromatography-mass spectrometry (GC-MS) analysis of the dichloromethane extracts. The lipophilic extractives of the ripe A. unedo berries ranged from 0.72% to 1.66% (w/w of dry weight), and consisted mainly of triterpenoids, fatty acids and sterols. Minor amounts of long chain aliphatic alcohols and tocopherols were also identified. Forty-one compounds were identified and among these, ursolic acid, lupeol, α-amyrin, linoleic and α-linolenic acids, and ß-sitosterol were highlighted as the major components. To the best of our knowledge the current research study provides the most detailed phytochemical repository for the lipophilic composition of A. unedo, and offers valuable information for future valuation and exploitation of these berries.


Assuntos
Ericaceae/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lipídeos/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Fitosteróis/análise
20.
Foods ; 12(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37372643

RESUMO

Port wine's prominence worldwide is unequivocal and the grape spirit, which comprises roughly one fifth of the total volume of this fortified wine, is also a contributor to the recognized quality of this beverage. Nonetheless, information about the influence of the grape spirit on the final aroma of Port wine, as well as its volatile composition, is extremely limited. Moreover, the aroma characteristics of Port wines are modulated mainly by their volatile profiles. Hence, this review presents a detailed overview of the volatile composition of the fortification spirit and Port wine, along with the methodologies employed for their characterization. Moreover, it gives a general overview of the Douro Demarcated Region (Portugal) and the relevance of fortification spirit to the production of Port wine. As far as we know, this review contains the most extensive database on the volatile composition of grape spirit and Port wine, corresponding to 23 and 208 compounds, respectively. To conclude, the global outlook and future challenges are addressed, with the position of the analytical coverage of the chemical data on volatile components discussed as crucial for the innovation centered on consumer preferences.

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