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1.
Mycology ; 12(3): 216-229, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34552812

RESUMEN

Ectomycorrhizal fungi are crucial for forests sustainability. For Castanea sativa, ectomycorrhizal fungus Pisolithus tinctorius is an important mutualist partner. Saprotrophic fungi Hypholoma fasciculare, although used for biocontrol of Armillaria root disease, it negatively affected the interaction between the P. tinctorius and plant host roots, by compromise the formation of P. tinctorius-C. sativa mycorrhizae. In this work, fungal morphology during inhibition of H. fasciculare against P. tinctorius was elucidated. P. tinctorius growth was strongly affected by H. fasciculare, which was significantly reduced after six days of co-culture and become even more significant through time. During this period, P. tinctorius developed vesicles and calcium oxalate crystals, which were described as mechanisms to stress adaption by fungi. H. fasciculare produced different volatile organic compounds in co-cultures over time and differ between single or in dual-species. H. fasciculare highly produced sesquiterpenes (namely, α-muurolene) and nitrogen-containing compounds, which are recognised as having antimicrobial activity.

2.
Food Chem ; 270: 518-526, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30174081

RESUMEN

A method based on headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-triple quadrupole/mass spectrometry detection (GC-TQ/MS) with a prior derivatization step with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was developed to quantify carbonyl compounds in different categories of Port wines. Optimal extraction conditions were obtained incubating 2 ml of wine with 2.3 g/l of PFBHA for 10 min and extracted during 20 min at 32 °C. The method was validated for 38 carbonyl compounds (alkanals, alkenals, Strecker aldehydes, dialdehydes, ketones and furan aldehydes) with regard to linearity, repeatability, inter and intra-day precision and accuracy, showing that the method is suitable for the determination of carbonyl compounds in wines. Tawny wines with 'indication of age' (10-40 years old) presented the highest levels of some carbonyl compounds, such as propanal, pentanal, hexanal, Strecker aldehydes, diacetyl, methyl glyoxal, 3-pentanone and 2-furfural, whereas Ruby wines were characterized by the highest amounts of some unidentified compounds.


Asunto(s)
Aldehídos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Cetonas/análisis , Microextracción en Fase Sólida/métodos , Vino/análisis
3.
Toxicol Lett ; 295: 22-31, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29852275

RESUMEN

Two methods based on headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) were developed to study in vitro the volatile exometabolome, which were then further tested in a pilot study to evaluate galactosamine-induced hepatotoxicity. The analysis of volatile organic compounds (VOCs) was carried out directly in the headspace of the cell culture medium, while some other volatile organic compounds such as volatile carbonyl compounds (VCCs) (aldehydes and ketones) were determined in the headspace of the cell culture medium after a previous derivatization step with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). Fiber selection was performed using a univariate mode, whereas a central composite design (CCD) was used in the optimization of several other parameters that affect the extraction conditions. VOCs showed optimal extraction results using a DVB/CAR/PDMS fiber, by adding 0.43 g of NaCl to a sample volume of 2 mL and allowing the sample to equilibrate for 10 min at 45 °C with a subsequent extraction for 39 min at the same temperature. For VCCs, the best extraction response was achieved after in-solution (2 mL) derivatization with 0.94 g L-1 of PFBHA (final concentration), followed by an incubation period of 6 min and an extraction time of 37 min at 53 °C, using a PDMS/DVB fiber. The applicability of both optimized methods was then tested, through a untargeted study, on cell culture medium samples obtained from primary mouse hepatocytes (PMH) exposed to three low concentrations (LC01, LC10 and LC30) of the well-known hepatotoxic agent galactosamine (GalN). The results obtained by both methods showed that volatile compounds from GalN exposed cells are separated from controls in a concentration-dependent manner. Several volatile compounds, namely aldehydes, ketones and alcohols, suffered significant alterations, suggesting that GalN induces marked metabolic alterations in cells even at low, non-toxic concentrations. Although preliminary, this metabolomics approach proved its potential to be used in future studies to evaluate toxicity of different xenobiotics.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Galactosamina/toxicidad , Cromatografía de Gases y Espectrometría de Masas , Hepatocitos/metabolismo , Hígado/metabolismo , Metabolómica/métodos , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/metabolismo , Animales , Biomarcadores/metabolismo , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Relación Dosis-Respuesta a Droga , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratones , Proyectos Piloto , Prueba de Estudio Conceptual
4.
J Cell Mol Med ; 21(9): 2092-2105, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28378454

RESUMEN

The analysis of volatile organic compounds (VOCs) emanating from biological samples appears as one of the most promising approaches in metabolomics for the study of diseases, namely cancer. In fact, it offers advantages, such as non-invasiveness and robustness for high-throughput applications. The purpose of this work was to study the urinary volatile metabolic profile of patients with renal cell carcinoma (RCC) (n = 30) and controls (n = 37) with the aim of identifying a potential specific urinary volatile pattern as a non-invasive strategy to detect RCC. Moreover, the effect of some confounding factors such as age, gender, smoking habits and body mass index was evaluated as well as the ability of urinary VOCs to discriminate RCC subtypes and stages. A headspace solid-phase microextraction/gas chromatography-mass spectrometry-based method was performed, followed by multivariate data analysis. A variable selection method was applied to reduce the impact of potential redundant and noisy chromatographic variables, and all models were validated by Monte Carlo cross-validation and permutation tests. Regarding the effect of RCC on the urine VOCs composition, a panel of 21 VOCs descriptive of RCC was defined, capable of discriminating RCC patients from controls in principal component analysis. Discriminant VOCs were further individually validated in two independent samples sets (nine RCC patients and 12 controls, seven RCC patients with diabetes mellitus type 2) by univariate statistical analysis. Two VOCs were found consistently and significantly altered between RCC and controls (2-oxopropanal and, according to identification using NIST14, 2,5,8-trimethyl-1,2,3,4-tetrahydronaphthalene-1-ol), strongly suggesting enhanced potential as RCC biomarkers. Gender, smoking habits and body mass index showed negligible and age-only minimal effects on the urinary VOCs, compared to the deviations resultant from the disease. Moreover, in this cohort, the urinary volatilome did not show ability to discriminate RCC stages and histological subtypes. The results validated the value of urinary volatilome for the detection of RCC and advanced with the identification of potential RCC urinary biomarkers.


Asunto(s)
Biomarcadores de Tumor/orina , Carcinoma de Células Renales/orina , Cromatografía de Gases y Espectrometría de Masas , Neoplasias Renales/orina , Metabolómica , Compuestos Orgánicos Volátiles/orina , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Análisis Discriminante , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Análisis de Componente Principal
5.
Ciênc. cuid. saúde ; 15(1): 93-100, 07/06/2016.
Artículo en Inglés, Portugués | LILACS, BDENF - Enfermería | ID: biblio-1120733

RESUMEN

Estudo qualitativo com objetivo de analisar como ocorre o acolhimento pelos trabalhadores de um hospital público do estado da Bahia aos familiares de pessoas hospitalizadas na Unidade de Terapia Intensiva (UTI). Participaram deste estudo sete trabalhadores e oito familiares, totalizando quinze participantes. Para apreensão dos dados, utilizou-se a entrevista semiestruturada, sendo a coleta realizada no período de janeiro a março de 2104. Os achados foram submetidos à análise temática de conteúdo e organizados em categorias:Concepções do acolhimento na UTI por familiares e trabalhadores; Estratégias para promover o acolhimento aos familiares na UTI: facilidades, dificuldades e perspectivas. Este estudo demonstrou que as ações voltadas para o acolhimento aos familiares de pessoas hospitalizadas em UTI, pelos trabalhadores, são pontuais e quando realizadas, acontecem de acordo a concepção e a disponibilidade de cada trabalhador. Consideramos que é preciso que o acolhimento nãoseja visto somente como uma postura ética dos trabalhadores, mas sobretudo, como uma diretriz organizacional, em que se faça primordial a qualidade da assistência.


This is a qualitative study that aims to analyze how the hosting of relatives of people hospitalized in the Intensive Care Unit (ICU) is carried out by the workers of a public hospital of the state of Bahia.Fifteensubjects (seven workers and eight family members) participated in the study. For data collection, we used a semi-structured interview and collection was carried out from January to March 2014.The findings were submitted to thematic content analysis, and were organized into two categories: "hosting conceptions in the ICU by family members and workers" and "Strategies to promote the hosting to family members in the ICU:facilities, problems and prospects". This study has demonstrated that the actions aimed atwelcoming the relatives of people hospitalized in ICUs are punctual and, when performed, take place according to the design and the availability of each employee.It is considered that hosting should not be seen only as an ethical position of workers, but mainly as an organizational guideline, in which care quality is a priority.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Familia , Salud Laboral , Acogimiento , Calidad de la Atención de Salud , Personal de Salud , Humanización de la Atención , Relaciones Familiares , Hospitalización , Unidades de Cuidados Intensivos
6.
Talanta ; 148: 486-93, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26653476

RESUMEN

A new and simple analytical approach consisting of an automated headspace solid-phase microextraction (HS-SPME) sampler coupled to gas chromatography-ion trap/mass spectrometry detection (GC-IT/MS) with a prior derivatization step with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was developed to detect volatile carbonyl metabolites with low molecular weights in human urine. A central composite design (CCD) was used to optimise the PFBHA concentration and extraction conditions that affect the efficiency of the SPME procedure. With a sample volume of 1 mL, optimal conditions were achieved by adding 300 mg/L of PFBHA and allowing the sample to equilibrate for 6 min at 62°C and then extracting the samples for 51 min at the same temperature, using a divinylbenzene/polydimethylsiloxane (DVB/PDMS) fibre. The method allowed the simultaneous identification and quantification of 44 carbonyl compounds consisting of aldehydes, dialdehydes, heterocyclic aldehydes and ketones. The method was validated with regards to the linearity, inter- and intra-day precision and accuracy. The detection limits ranged from 0.009 to 0.942 ng/mL, except for 4-hydroxy-2-nonenal (15 ng/mL), and the quantification limits varied from 0.029 to 1.66 ng/mL, except for butanal (2.78 ng/mL), 2-butanone (2.67 ng/mL), 4-heptanone (3.14 ng/mL) and 4-hydroxy-2-nonenal (50.0 ng/mL). The method accuracy was satisfactory, with recoveries ranging from 90 to 107%. The proof of applicability of the methodology was performed in a pilot target analysis of urine samples obtained from 18 healthy smokers and 18 healthy non-smokers (control group). Chemometric supervised analysis was performed using the volatile patterns acquired for these samples and clearly showed the potential of the volatile carbonyl profiles to discriminate urine from smoker and non-smoker subjects. 5-Methyl-2-furfural (p<0.0001), 2-methylpropanal, nonanal and 2-methylbutanal (p<0.05) were identified as potentially useful biomarkers to identify smoking habits.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/normas , Fumar/orina , Microextracción en Fase Sólida/normas , Compuestos Orgánicos Volátiles/orina , Adulto , Aldehídos/orina , Biomarcadores/orina , Femenino , Humanos , Hidroxilaminas/orina , Cetonas/orina , Masculino , Persona de Mediana Edad , Proyectos Piloto , Adulto Joven
7.
Eur J Cancer ; 50(11): 1993-2002, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24820933

RESUMEN

A new and simple analytical approach consisting of headspace-solid phase microextraction (HS-SPME) sampling coupled with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed to study the volatile human urinary metabolome. A central composite design (CCD) was used in the optimisation of extraction conditions. Fibre selection and evaluation of pH influence were performed using an univariate mode and the influence of other parameters, such as the time and temperature of extraction, time of incubation and salt addition, that affect the efficiency of the SPME sampling, was carried out using a CCD. With a sample volume of 2 mL, the optimal conditions in terms of total response values and reproducibility were achieved by performing analyses with a divinylbenzene/polydimethylsiloxane (DVB/PDMS) fibre, in an acidic pH (pH 2) with the addition of 0.59 g of NaCl, allowing the sample to equilibrate for 9 min and extracting at 68 °C for 24 min. The applicability of the optimised method was then tested in a pilot non-target analysis of urine samples obtained from patients with renal cell carcinoma (RCC) and healthy individuals. Chemometric unsupervised analyses performed on the volatile pattern acquired for these samples clearly showed the potential of volatile urinary metabolome to discriminate between RCC and control patients.


Asunto(s)
Biomarcadores de Tumor/orina , Carcinoma de Células Renales/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Neoplasias Renales/orina , Microextracción en Fase Sólida/métodos , Adulto , Anciano , Carcinoma de Células Renales/diagnóstico , Femenino , Humanos , Neoplasias Renales/diagnóstico , Masculino , Metaboloma , Persona de Mediana Edad , Proyectos Piloto
8.
Talanta ; 118: 292-303, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24274300

RESUMEN

Mushrooms are known all over the world both due to the remarkable gastronomic value of some species and for severe intoxications mediated by other species that are frequently difficult to distinguish from the edible ones, by the common user. Therefore, it is important to develop strategies to discover molecules that can identify mushroom species. In the present work, two GC-MS methodologies were applied in the chemical characterization of 22 mushroom species (12 edible, 3 toxic and 7 potentially toxic) - a multi-target procedure to simultaneously determine amino acids (AA), fatty acids (FA) and sterols by previous derivatization procedure with MSTFA, and a Head Space-Solid Phase Microextraction method to determine volatiles. For both methods, two approaches to data analysis were used: (I) targeted analysis, to identify and quantify AA, FA sterols and volatiles; (II) untargeted analysis, including Principal Component Analysis and Partial Least Square Discriminant Analysis, in order to identify metabolites/metabolite pattern with potential species identification and/or differentiation. Multi-target experiment allowed the identification and quantification of twenty one primary metabolites (9 AA, 11 FA and 1 sterol). Furthermore, through untargeted data analysis, it was possible to identify a 5-carbon sugar alcohol structure molecule, which was tentatively identified as xylitol or adonitol, with potential to be a species-marker of the edible Suillus bovinus mushrooms. Volatile profiling studies resulted in the identification of the main volatiles in mushrooms. Untargeted analysis allowed the identification of 6 molecules that can be species- or genus-specific: one secondary metabolite specific to the edible species Lycoperdon perlatum, an ester of hexanoic acid, tentatively identified as allyl or vinyl caproate; and five other secondary metabolites, whose identification was not achieved, which were only detected in Lactarius aurantiacus specimens (edibility/toxicity unknown).


Asunto(s)
Agaricales/química , Análisis Discriminante , Cromatografía de Gases y Espectrometría de Masas/métodos , Metabolómica/métodos , Análisis de Componente Principal , Humanos , Microextracción en Fase Sólida
9.
Talanta ; 117: 523-31, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24209376

RESUMEN

An automated headspace solid-phase microextraction (HS-SPME) combined with gas chromatography and ion trap mass spectrometry detection (GC-IT/MS) was developed in order to quantify a large number of carbonyl compounds in beers. Carbonyl compounds were previously derivatized with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). Volatile carbonyl compounds associated with staling beer aroma includes alkanals, alkenals, alkadienals, dicarbonyl compounds, Strecker aldehydes, ketones and furans. The HS-SPME was performed using a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber. The procedures were optimized for HS-SPME pre-incubation temperature and time, extraction temperature and time, and PFBHA addition. A central composite design was used in the optimization of extraction conditions and PFBHA addition. The volatile compounds showed optimal extraction incubating 5 ml of beer with 700 mg l(-1) of PFBHA for 7 min and extracted for more 20 min at 45 °C. The method was validated with regard to the linearity, repeatability, inter and intra-day precision and accuracy. The method achieved detection limits ranging from 0.003 to 0.510 µg l(-1), except for furans (1.54-3.44 µg l(-1)). The quantification limits varied from 0.010 to 1.55 µg l(-1), except for 2-furfural (4.68 µg l(-1)), 5-methyl-2-furfural (5.82 µg l(-1)) and 5-hyfroxymethylfurfural (10.4 µg l(-1)). Repeatability values of all compounds were lower than 17%. The method accuracy was satisfactory with recoveries ranging from 88% to 114%. The validated method showed to be suitable for a fast and reliable determination of main carbonyl compounds in beers.


Asunto(s)
Aldehídos/análisis , Cerveza/análisis , Dimetilpolisiloxanos/química , Furanos/análisis , Hidroxilaminas/química , Cetonas/análisis , Polivinilos/química , Análisis Factorial , Cromatografía de Gases y Espectrometría de Masas/estadística & datos numéricos , Humanos , Límite de Detección , Reproducibilidad de los Resultados , Microextracción en Fase Sólida , Temperatura
10.
Talanta ; 101: 177-86, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23158309

RESUMEN

An automated headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed in order to quantify a large number of volatile compounds in wines such as alcohols, ester, norisoprenoids and terpenes. The procedures were optimized for SPME fiber selection, pre-incubation temperature and time, extraction temperature and time, and salt addition. A central composite experimental design was used in the optimization of the extraction conditions. The volatile compounds showed optimal extraction using a DVB/CAR/PDMS fiber, incubation of 5 ml of wine with 2g NaCl at 45 °C during 5 min, and subsequent extraction of 30 min at the same temperature. The method allowed the identification of 64 volatile compounds. Afterwards, the method was validated successfully for the most significant compounds and was applied to study the volatile composition of different white wines.


Asunto(s)
Automatización , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Límite de Detección , Reproducibilidad de los Resultados
11.
Food Chem ; 126(4): 1599-607, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25213933

RESUMEN

Ammonium salts were added to white grape musts, before alcoholic fermentation, in order to evaluate their influence on the heavy sulphur compound and aliphatic higher alcohol composition of resulting wines. Six grape musts were used (Trajadura, Pedernã, Loureiro, Azal Branco, Avesso and Alvarinho). Ammonium supplementation of Trajadura and Pedernã grape musts, with the highest nitrogen level, did not influence the content of heavy sulphur compounds and aliphatic higher alcohols in wines; however, the addition of ammonium salts to grape musts with low initial nitrogen content, such as Loureiro, Azal Branco and Avesso, led to a higher production of 1-propanol and a lower production of isoamyl alcohols and sulphur compounds, e.g. S-methyl thioacetate, 2-mercaptoethanol, acetic acid-3-(methylthio)propyl ester, 3-mercapto-1-propanol, 4-(methylthio)-1-butanol, 3-(ethylthio)-1-propanol, 3-methylthiopropionic acid and N-3-(methylthiopropyl)acetamide. For Alvarinho grape must, a decrease in sulphur compound concentrations in wines was only observed for 3-methylthiopropionic acid, acetic acid-3-(methylthio)propyl ester and 2-mercaptoethanol.

12.
Int J Food Microbiol ; 103(3): 285-94, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16099313

RESUMEN

Strains of Hanseniaspora uvarum, Hanseniaspora guilliermondii and Saccharomyces cerevisiae were used as pure or mixed starter cultures in commercial medium, in order to compare their kinetic parameters and fermentation patterns. In pure and mixed cultures, yeasts presented similar ethanol yield and productivity. Pure cultures of H. uvarum and S. cerevisiae showed a specific growth rate of 0.38 h(-1); however, this value decreased when these yeasts were grown in mixed cultures with H. guilliermondii. The specific growth rate of pure cultures of H. guilliermondii was 0.41 h(-1) and was not affected by growth of other yeasts. H. guilliermondii was found to be the best producer of 2-phenylethyl acetate and 2-phenylethanol in both pure and mixed cultures. In pure cultures, H. uvarum led to the highest contents of heavy sulphur compounds, but H. guilliermondii and S. cerevisiae produced similar levels of methionol and 2-methyltetrahydrothiophen-3-one. Growth of apiculate yeasts in mixed cultures with S. cerevisiae led to amounts of 3-methylthiopropionic acid, acetic acid-3-(methylthio)propyl ester and 2-methyltetrahydrothiophen-3-one similar to those obtained in a pure culture of S. cerevisiae; however, growth of apiculate yeasts increased methionol contents of fermented media.


Asunto(s)
Fermentación , Vino/microbiología , Levaduras/crecimiento & desarrollo , Levaduras/metabolismo , Alcoholes/análisis , Técnicas de Cocultivo , Recuento de Colonia Microbiana , Ésteres/análisis , Microbiología Industrial , Cinética , Dinámica Poblacional , Saccharomyces cerevisiae/metabolismo , Compuestos de Azufre/análisis , Vino/análisis
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