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1.
J Dairy Sci ; 102(6): 5005-5018, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005329

RESUMO

Thermization is a sub-pasteurization heat treatment of cheese milk (at 57-68°C for 15-30 s) aimed to reduce the number of undesirable microbial contaminants with reduced heat damage to the indigenous milk enzymes. In this work, the effects of milk thermization on the compositional parameters, proteolysis indices, free fatty acid levels, and low molecular weight metabolite profiles of ovine cheese were studied. Cheese samples at different ripening stages and produced in 2 different periods of the year were analyzed. While the effects of milk thermization on cheese macro-compositional parameters and free fatty acid levels were not evident due to the predominant effects of milk seasonality and cheese ripening stage, the gas chromatography-mass spectrometry based metabolomics approach of ovine cheese produced from raw and thermized milk highlighted strong differences at the metabolite level. Discriminant analysis applied to gas chromatography-mass spectrometry data provided an excellent classification model where cheese samples were correctly classified as produced from raw or thermized milk. The metabolites that mostly changed due to the thermization process belonged to the classes of free amino acids and saccharides. Gas chromatography-mass spectrometry-based metabolomics has proven to be a valid tool to study the effect of mild heat treatments on the polar metabolite profile in ovine cheese.


Assuntos
Queijo , Leite/química , Pasteurização , Aminoácidos/química , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Metabolômica , Ovinos
2.
Food Res Int ; 119: 869-875, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884727

RESUMO

Despite the worldwide consumption of bovine milk, dairy products from small ruminants, such as goat's and sheep's milk, are gaining a large interest especially in the Mediterranean area. The aim of this work was to study the metabolite profiles of 30 sheep's and 28 goat's milk using an untargeted metabolomics approach by a gas chromatography coupled with mass spectrometry (GC-MS) analysis. Results showed several differences in the metabolite profiles: arabitol, citric acid, α-ketoglutaric acid, glyceric acid, myo-inositol, and glycine were more abundant in sheep's milk, while goat's milk had higher levels of mannose-6-phosphate, isomaltulose, valine, pyroglutamic acid, leucine, and fucose. Associations between metabolite profile and milk compositional traits were also found. Predictive capabilities of statistical models indicated a good correlation between the metabolite profile and the protein content in sheep's milk, and with the fat content in goat's milk. This work leads to a better understanding of milk metabolites in small ruminants and their role in the evaluation of milk properties.


Assuntos
Metabolômica/métodos , Leite/química , Animais , Ácido Cítrico/análise , Laticínios/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Cabras , Inositol/análise , Manosefosfatos/análise , Proteínas do Leite/análise , Análise Multivariada , Carneiro Doméstico
3.
J Helminthol ; 91(4): 447-453, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27329583

RESUMO

Infections by gastrointestinal nematodes negatively affect small ruminant health and at the same time cause substantial economic losses worldwide. Because resistance to conventional anthelmintic compounds is growing, target studies evaluating the effectiveness of alternative ingredients of botanical origin on gastrointestinal nematodes are needed. In this study, we evaluated the in vitro anthelmintic activity of Ruta chalepensis L. extracts on the third-stage larvae of sheep gastrointestinal nematodes. A methanol extract showed the highest anthelmintic activity, with an EC50 = 0.10 ± 0.06 mg/ml after 96 h, while the essential oil had an EC50 = 1.45 ± 1.22 mg/ml after 48 h. Moreover, three secondary metabolites of the essential oil, i.e. 2-decanone, 2-nonanone and 2-undecanone, showed EC50 values of 0.07 ± 0.06, 0.25 ± 0.29 and 0.88 ± 0.73 mg/ml at 24 h, respectively. The present study indicated that the R. chalepensis methanol extract, the essential oil and its metabolites 2-decanone, 2-nonanone and 2-undecanone showed promising anthelmintic activity on gastrointestinal nematodes.


Assuntos
Anti-Helmínticos/farmacologia , Helmintíase/parasitologia , Enteropatias Parasitárias/parasitologia , Nematoides/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Ruta/química , Doenças dos Ovinos/parasitologia , Animais , Anti-Helmínticos/isolamento & purificação , Bioensaio , Larva/efeitos dos fármacos , Nematoides/isolamento & purificação , Testes de Sensibilidade Parasitária , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ovinos
4.
Neuropharmacology ; 99: 705-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26327678

RESUMO

The synthetic cannabinoid 1-pentyl-3-(1-naphthoyl)-indole (JWH-018) has been detected in about 140 samples of a smokable herbal mixture termed "Spice". JWH-018 is a CB1 and CB2 agonist with a higher affinity than Δ9-THC. In order to investigate the neurobiological substrates of JWH-018 actions, we studied by microdialysis in freely moving rats the effect of JWH-018 on extracellular dopamine (DA) levels in the nucleus accumbens (NAc) shell and core and in the medial prefrontal cortex (mPFC). JWH-018, at the dose of 0.25 mg/kg i.p., increased DA release in the NAc shell but not in the NAc core and mPFC. Lower (0.125 mg/kg) and higher doses (0.50 mg/kg) were ineffective. These effects were blocked by CB1 receptor antagonists (SR-141716A and AM 251) and were absent in mice lacking the CB1 receptor. Ex vivo whole cell patch clamp recordings from rat ventral tegmental area (VTA) DA neurons showed that JWH-018 decreases GABAA-mediated post-synaptic currents in a dose-dependent fashion suggesting that the stimulation of DA release observed in vivo might result from disinhibition of DA neurons. In addition, on the "tetrad" paradigm for screening cannabinoid-like effects (i.e., hypothermia, analgesia, catalepsy, hypomotility), JWH-018, at doses of 1 and 3 mg/kg i.p., produced CB1 receptor-dependent behavioural effects in rats. Finally, under appropriate experimental conditions, rats (20 µg/kg/inf i.v., FR3; nose-poking) and mice (30 µg/kg/inf i.v., FR1; lever-pressing) self-administer intravenously JWH-018. In conclusion, JWH-018 shares with the active ingredient of Marijuana, Δ9-THC, CB1-dependent reinforcing and DA stimulant actions.


Assuntos
Agonistas de Receptores de Canabinoides/administração & dosagem , Dopamina/metabolismo , Indóis/administração & dosagem , Naftalenos/administração & dosagem , Administração Intravenosa , Animais , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/fisiologia , Relação Dose-Resposta a Droga , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microdiálise , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Técnicas de Patch-Clamp , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptores de GABA-A/metabolismo , Autoadministração , Especificidade da Espécie , Técnicas de Cultura de Tecidos , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/fisiologia
5.
J Agric Food Chem ; 56(3): 1084-90, 2008 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-18181568

RESUMO

Pome trees, apple, pear, and quince, are classified into the subfamily Pomoideae, belonging to the Rosaceae family. Their autumnal fruits are consumed worldwide in different forms, that is, fresh or transformed into jams, jelly, juices, etc. Their well-established beneficial properties to human health were found mainly related to their phenolic content. Pulp and peel aqueous acetone extracts obtained from Tunisian fruits at commercial maturity were comparatively evaluated for their phenolic profiles and antioxidant and antimicrobial potentials. The phenolic compounds present in the extracts were identified and quantified using RP-HPLC-DAD and ESI-MS techniques. Significant differences in the chromatographic profiles among these fruits, as well as between pulp and peel extracts of each fruit, were observed. Quince, followed by 'Red Delicious', peel extracts showed the highest phenolic content (160.33 and 110.90 mg/100 g of fresh weight). The stronger inhibitory effect on DPPH radicals corresponded to those obtained from peel materials. A comparative analysis of the antimicrobial potential against a range of microorganism strains was also carried out. Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus were the most sensitive to the active extracts. Among the examined phenolic extracts, 'Red Delicious' and quince peels showed the highest effects for inhibiting bacteria growth. Minimum inhibitory and bactericide concentrations ranged from 10(2) to 10(4) microg of polyphenol/mL. Red skin apple and quince peels could be of great interest as important antioxidant and antimicrobial polyphenol sources.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Flavonoides/análise , Frutas/química , Fenóis/análise , Extratos Vegetais/química , Acetona , Cromatografia Líquida de Alta Pressão , Malus/química , Polifenóis , Pyrus/química , Rosaceae/química , Espectrometria de Massas por Ionização por Electrospray , Tunísia
6.
J Agric Food Chem ; 55(5): 2043-8, 2007 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-17279767

RESUMO

The interaction of ochratoxin A (OTA) and 20 yeast strains of Saccharomyces cerevisiae and Kloeckera apiculata during alcoholic fermentation was studied. Levels of OTA were determined in the fermentation liquid and in the yeast cells solid using a high-performance liquid chromatography system with a fluorescence detector. Yeast cells do not adsorb OTA, and for all yeasts, OTA levels did not affect the alcoholic fermentation. Some yeast strains reduced levels of OTA, whereas other strains did not show any effect demonstrating that OTA level reduction is not a genus species characteristic but a strain trait.


Assuntos
Ascomicetos/metabolismo , Carcinógenos/análise , Ocratoxinas/análise , Saccharomyces cerevisiae/metabolismo , Absorção , Ascomicetos/química , Fermentação , Saccharomyces cerevisiae/química , Vinho/microbiologia
7.
Food Addit Contam ; 23(3): 289-94, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16517530

RESUMO

Famoxadone is a recently applied fungicide to vines that belongs to the oxazolidinedione family. The fate of famoxadone was studied by considering the decay ratio of this fungicide during the maturation of grapes and wine production. The main factors affecting the presence of fungicide residues such as fruit growth, photodegradation, evaporation, thermodegradation and co-distillation were studied with model systems. An experimental field was treated with a commercial product containing famoxadone at the recommended dose. After this application, residues of famoxadone were found in grapes at 0.27 +/- 0.06 mg kg(-1). In this field experiment, the half-life t(1/2) of famoxadone, which is described by pseudo-first-order kinetics (R2 = 0.74), was 18 +/- 6 days, resulting from the photodegradation. The famoxadone residue levels in grapes were below the established maximum residues level for Europe (2 mg kg(-1)), whilst levels in wine, carried out with and without maceration, were below the calculated limit of detection of the method.


Assuntos
Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Oxazóis/análise , Resíduos de Praguicidas/análise , Vitis/química , Vinho/análise , Fermentação , Manipulação de Alimentos/métodos , Fungicidas Industriais/farmacologia , Meia-Vida , Metacrilatos/análise , Metacrilatos/farmacologia , Modelos Biológicos , Oxazóis/farmacologia , Resíduos de Praguicidas/farmacologia , Estrobilurinas , Luz Solar , Temperatura , Vitis/efeitos dos fármacos , Vitis/crescimento & desenvolvimento
8.
J Agric Food Chem ; 49(7): 3161-3, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11453746

RESUMO

A simple and rapid HPLC method to evaluate residues of the major ryanoids (ryanodine and dehydroryanodine) on three fruits (olives, apples, and pears) has been developed. The pesticides were extracted from the fruits with hexane and acetone solution (1:1, v/v). Cleanup was carried out with aminopropyl-bonded silica cartridges. This method is characterized by recovery >75%, precision <11% RSD, and sensitivity of 0.020 mg/kg. The method can also be used to determine the level of active ingredients in ryania powdery wood.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Praguicidas/análise , Rianodina/análise , Rosales/química , Sensibilidade e Especificidade
9.
J Agric Food Chem ; 48(3): 915-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10725173

RESUMO

Field trials were carried out to evaluate whether folpet sprayed on grapevines penetrated the epicuticular wax and cell walls of grapes. Folpet showed poor penetration into the epicuticular wax; it was found almost totally on the surface. Despite its low solubility in water, perhaps due to the presence of adjuvants, its residues showed such a high resistance to washing that the action of rain was negligible in decreasing residues.


Assuntos
Fungicidas Industriais/química , Resíduos de Praguicidas/análise , Ftalimidas/química , Doenças das Plantas , Rosales , Cromatografia Gasosa , Qualidade de Produtos para o Consumidor , Humanos , Solubilidade , Propriedades de Superfície
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