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Interaction between two co-occurring fungi present in chestnut orchards

Hypholoma fasciculare is a wood-decaying basidiomycete with a worldwide distribution, including tropical, temperate and boreal forest ecosystems. In Trás-os-Montes region (Northeast of Portugal) this species is commonly present in soils of several habitats, including chestnut and oak tree forests. The ectomycorrhizal fungus Pisolithus tinctorius is another species with high occurrence in those ecosystems. The p...

Relationship between nitrogen content in grape volatiles, namely heavy sulphur ...

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 ...

Do bioactive carotenoids contribute to the color of edible mushrooms?

Carotenoids are biologically active phytochemicals present as micro-components in fruits and vegetables, being responsible for their yellow, orange and red colors. The chromatographic behavior and the UV absorption spectrum provided by HPLC-DAD analysis constitute the clues for their identification. Mushrooms are of increasing importance in modern nutrition and medicine, due to the presence of metabolites with ...

Volatile sulphur compounds composition of monovarietal white wines

The sulphur compounds composition of wines produced experimentally from six white cultivars (Alvarinho, Loureiro, Trajadura, Pedernã, Azal Branco and Avesso) was evaluated during two consecutive vintages. Results show that wines could be differentiated according to their sulphur compounds content. In general, Loureiro, Trajadura and Pedernã cultivars led to wines with low concentrations of sulphur compounds; ho...

Chemical reactivity of paraquat with the previously validated antidote, sodium ...

Reactivity of paraquat with sodium salicylate: Formation of stable complexes

Sodium salicylate (NaSAL) has been shown to be a promising antidote for the treatment of paraquat (PQ) poisonings. The modulation of the pro-oxidant and pro-inflammatory pathways, as well as the antithrombogenic properties of NaSAL are probably essential features for the healing effects provided by this drug. Nevertheless, a possible direct chemical reactivity between PQ and NaSAL is also a putative pathway to ...

Study of major aromatic compounds in port wines from carotenoid degradation

The carotenoids degradation and the formation of volatiles were examined by simulating Port wine aging. A two year old red Port wine was saturated with oxygen, supplemented with lutein and b-carotene and kept at 60ºC during 87 h. A similar study was performed in a model wine solution. Results showed that the percentage decrease in lutein levels was, respectively, 79% and 95%, in the wine model solution and in t...

Simultaneous determination of ketoacids and dicarbonyl compounds, key Maillard ...

The aim of thiswork was the simultaneous determination of both ketoacids and dicarbonyl compounds in wine.Todetect ketoacidcompoundsin wine,amethodbasedonthequinoxaline derivativesby the reaction with diaminobenzene, currently employed to detectα-dicarbonyl compounds, was developed. The quinoxaline derivatives were detected by RP-HPLC with UV detection, which allows the determination of the major dicarbonyl com...

Carotenoid profile in grapes related to aromatic compounds in wines from Douro ...

The aim of this work was to characterize 8 representative grape varieties of the Douro Region using the carotenoid profile as it relates to aromatic compounds in the respective wines. Some other analyses, such as the determination of sugar, probable alcohol, pH, and total acidity, were also performed in an attempt to understand in which way the evaluated characteristics influenced by grape variety could contrib...

Nor-isoprenoids profile during port wine ageing—influence of some technological...

Nor-isoprenoid compounds, such as β-damascenone, β-ionone, 2,2,6-trimethylcyclohexanone (TCH), 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) and vitispirane were determined in 14 young port wines and 45 old port wines. As between the two groups of wines levels of these compounds are quite different, an experimental protocol was performed in order to determine which technological parameter (dissolved O2, free SO2...