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1.
Foods ; 12(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38137224

RESUMO

This study presents a tentative analysis of the lipid composition of 47 legume samples, encompassing species such as Phaseolus spp., Vicia spp., Pisum spp., and Lathyrus spp. Lipid extraction and GC/MS (gas chromatography with mass spectrometric detection) analysis were conducted, followed by multivariate statistical methods for data interpretation. Hierarchical Cluster Analysis (HCA) revealed two major clusters, distinguishing beans and snap beans (Phaseolus spp.) from faba beans (Vicia faba), peas (Pisum sativum), and grass peas (Lathyrus sativus). Principal Component Analysis (PCA) yielded 2D and 3D score plots, effectively discriminating legume species. Linear Discriminant Analysis (LDA) achieved a 100% accurate classification of the training set and a 90% accuracy of the test set. The lipid-based fingerprinting elucidated compounds crucial for discrimination. Both PCA and LDA biplots highlighted squalene and fatty acid methyl esters (FAMEs) of 9,12,15-octadecatrienoic acid (C18:3) and 5,11,14,17-eicosatetraenoic acid (C20:4) as influential in the clustering of beans and snap beans. Unique compounds, including 13-docosenoic acid (C22:1) and γ-tocopherol, O-methyl-, characterized grass pea samples. Faba bean samples were discriminated by FAMEs of heneicosanoic acid (C21:0) and oxiraneoctanoic acid, 3-octyl- (C18-ox). However, C18-ox was also found in pea samples, but in significantly lower amounts. This research demonstrates the efficacy of lipid analysis coupled with multivariate statistics for accurate differentiation and classification of legumes, according to their botanical origins.

2.
J Sci Food Agric ; 94(13): 2613-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24633679

RESUMO

BACKGROUND: In the present paper, a special method for derivatization of liposoluble extract of common wheat and spelt flours was employed which enables simultaneous detection of fatty acid and non-saponifiable lipid fractions. RESULTS: Gas chromatographic-mass spectrometric analytical data for both fractions were separately analyzed by multivariate statistical techniques to model classes of different common wheat and spelt cultivars. Cluster analysis was used, and the results obtained revealed that better discrimination of samples was achieved by analyzing the peak area after 16 min retention time (non-saponifiable lipids), rather than commonly used peak area between 12 and 16 min (fatty acid fraction), due to more distinctive positions of points in factor space, even though the distances between points for fatty acid fraction (12-16 min) were greater. Similar results were obtained by principal components analysis, where all wheat points almost coincided whereas spelt showed good discrimination. CONCLUSION: Comparison of chromatogram areas for non-saponifiable lipid fraction between common and spelt wheat showed a statistically high difference and hence has a potential for use in authenticity control.


Assuntos
Gorduras na Dieta/análise , Farinha/análise , Inspeção de Alimentos/métodos , Alimentos Orgânicos/análise , Modelos Biológicos , Extratos Vegetais/química , Triticum/química , Métodos Analíticos de Preparação de Amostras , Pão , Análise por Conglomerados , Farinha/normas , Alimentos Orgânicos/normas , Cromatografia Gasosa-Espectrometria de Massas , Interações Hidrofóbicas e Hidrofílicas , Análise Multivariada , Análise de Componente Principal , Sérvia , Solubilidade , Especificidade da Espécie , Triticum/crescimento & desenvolvimento
3.
J Sci Food Agric ; 93(8): 1996-2001, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23255302

RESUMO

BACKGROUND: Since there is an increasing demand on the world market for alternative crops suitable for organic production, spelt wheat (Triticum aestivum spp. spelta L.) is a highly attractive farming option. Alternaria species are widespread and infect a great variety of economically important crops. Certain species are known producers of mycotoxins. The aim of this study was to assess the protective effect of hulls covering the spelt kernels on Alternaria toxins. RESULTS: Alternariol (AOH) and alternariol monomethyl ether (AME) were evaluated in hulls and dehulled kernels after plant inoculation with one A. alternata and two different A. tenuissima isolates. Mycotoxins were determinated using high-performance liquid chromatography with dioade array detection. The detected levels of AOH and AME were four times higher in hulls compared to kernels in inoculation treatments. AOH was registered at levels ranging from 227 to 331 µg kg(-1) in dehulled kernels and from 433 up to 1647 µg kg(-1) in hulls. AME was predominant toxin detected in the range of 277 to 398 µg kg(-1) in dehulled kernels and from 1844 to 2183 µg kg(-1) in hulls, with highly significant difference to water control treatment. CONCLUSION: Obtained results indicate the significantly higher concentrations of Alternaria toxins in hulls than in dehulled kernels which implicate the possible protective effect of spelt wheat hulls.


Assuntos
Alternaria/fisiologia , Lactonas/química , Micotoxinas/química , Sementes/anatomia & histologia , Triticum/classificação , Contaminação de Alimentos , Sementes/química , Triticum/fisiologia
4.
J Forensic Sci ; 50(1): 204-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15831020

RESUMO

The aim of this study was to follow the postmortem ethanol production phenomenon under controlled experimental conditions (temperature, time interval) in different tissues. Specimens of blood, liver, skeletal muscle and kidney were taken from 30 corpses and no chemical preservatives were used in the specimens collected. Ethanol concentrations were detected by gas chromatography. All specimens stored at -20 degrees C and 4 degrees C did not show any change in ethanol concentration in an eight-day time interval. At 20 degrees C and 30 degrees C, all tissues, except blood, showed statistically significant ethanol production over the time interval tested. However, blood sample kept at 30 degrees C, showed statistically significant increase in ethanol production on the 2nd and 4th day comparing to the controls. Thus, we can state that postmortem ethanol production occurs in different tissues, and is increased at higher temperatures and, in general, it is in accordance with the course of time.


Assuntos
Depressores do Sistema Nervoso Central/farmacocinética , Etanol/farmacocinética , Mudanças Depois da Morte , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Temperatura , Fatores de Tempo , Distribuição Tecidual
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