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1.
Biology (Basel) ; 11(5)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35625350

RESUMO

Holothuria mammata is one of the most valuable species of sea cucumber, as well as one of the main target species harvested in the Mediterranean and NE-Atlantic regions. This study aims to describe the reproductive cycle of H. mammata in a coastal area of southwest Portugal. Monthly samplings were carried out for 19 months, with the concomitant collection of environmental data and biometric data. H. mammata had a sex ratio of 1:1.2 (male:female) and a size at first maturity of 142 mm for males and 167 mm for females. The gonadosomatic index (GI) peaked between April and May for both sexes. Gonad development started when days had a shorter photoperiod (9 to 13 h of sunlight) and lower seawater temperature (<15 °C), and spawning occurred later, with longer photoperiod (13 to 15 h of sunlight) and higher seawater temperature (>15 °C) and chlorophyll-a concentrations. The development of new studies to increase the biological and ecological knowledge of the populations of H. mammata is essential to create conditions for the domestication of broodstock in captivity, to allow the development of fishing regulations based on informed decisions and to create precise measures for the conservation of ecosystems.

2.
J Sci Food Agric ; 99(7): 3563-3571, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30628078

RESUMO

BACKGROUND: Wine colour is an important quality parameter, being the first sensorial attribute evaluated during wine tasting. The perception of wine colour can be different depending on many factors, including the depth of the sample under observation. The main objectives of the present study were to measure the colour of Port wines using CIE L*, a*, b* parameters at different depths with various instrumental techniques (spectrophotometry and colorimetry), and to compare the obtained results with the sensory (visual) perception of colour samples. RESULTS: Representative profiles of lightness (L*), hue (H*) and chroma (C*) at different depths were obtained using Port wine samples from various categories and ages. In general, relatively good correlations between the colorimetric and spectrophotometric methods were obtained for the L* and H* parameters. The results of the sensory tests also showed good correlations between the visually assessed hue scores and the colorimetric measurements of the H* parameter, particularly at the lower depths tested (up to 4.0 mm). CONCLUSIONS: Overall, the results indicate that the colorimetric method can be used for estimating wine colour parameters, providing useful information about the colour profile of wines at different depths. © 2019 Society of Chemical Industry.


Assuntos
Colorimetria/métodos , Espectrofotometria/métodos , Vinho/análise , Cor
3.
Food Chem ; 132(1): 630-6, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26434342

RESUMO

A multiresidue gas chromatographic method for the determination of six fungicides (captan, chlorthalonil, folpet, iprodione, procymidone and vinclozolin) and one acaricide (dicofol) in still and fortified wines was developed. Solid-phase microextraction (SPME) was chosen for the extraction of the compounds from the studied matrices and tandem mass spectrometry (MS/MS) detection was used. The extraction consists in a solvent free and automated procedure and the detection is highly sensitive and selective. Good linearity was obtained with correlation coefficients of regression (R(2))>0.99 for all the compounds. Satisfactory results of repeatability and intermediate precision were obtained for most of the analytes (RSD⩽20%). Recoveries from spiked wine ranged from 80.1% to 112.0%. Limits of quantification (LOQs) were considerably below the proposed maximum residue limits (MRLs) for these compounds in grapes and below the suggested limits for wine (MRLs/10), with the exception of captan.


Assuntos
Acaricidas/química , Fungicidas Industriais/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Vinho/análise , Acaricidas/análise , Fungicidas Industriais/análise
4.
J Agric Food Chem ; 59(13): 6847-55, 2011 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-21553896

RESUMO

The present work describes a solid-phase microextraction (SPME) gas chromatography-tandem mass spectrometry (MS/MS) method to quantify 24 pesticides in fortified white wine and fortified red wine. In this study "fortified wine" refers to a wine in which fermentation is arrested before completion by alcohol distillate addition, allowing sugar and alcoholic contents to be higher (around 80-100 g/L total sugars and 19-22% alcohol strength (v/v)). The analytical method showed good linearity, presenting correlation coefficients (R(2)) ≥ 0.989 for all compounds. Limits of detection (LOD) and quantitation (LOQ) in the ranges of 0.05-72.35 and 0.16-219.23 µg/L, respectively, were obtained. LOQs are below the maximum residue levels (MRL) set by European Regulation for grapes. The proposed method was applied to 17 commercial fortified wines. The analyzed pesticides were not detected in the wines tested.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise , Microextração em Fase Sólida , Vinho/análise , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Controle de Qualidade , Espectrometria de Massas em Tandem
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