With a characteristic flavour and aroma, “Maçã de Alcobaça” are apples produced in the western re... more With a characteristic flavour and aroma, “Maçã de Alcobaça” are apples produced in the western region of the mainland of Portugal. Given the known influence of pre-harvest cultural techniques and post-harvest conservation methods on fruit quality, this work evaluated the effect of cultural factors and conservation methods on the volatile profile of ‘Gala’ apples. Tests were carried out during four seasons (2018 to 2021) in two ‘Gala’ apple orchards (F and S) maintained with different irrigation rates and nitrogen fertilisation [normal irrigation and normal nitrogen (Control, NINN), normal irrigation and excess nitrogen (NIEN), excess irrigation and normal nitrogen (EINN), excess irrigation and excess nitrogen (EIEN)], and under three storage conditions [Controlled Atmosphere + 1-methylcyclopropene (CA+1-MCP), Dynamic Controlled Atmosphere (DCA) and DCA+1-MCP]. The intact fruit volatiles were isolated by headspace solid–phase microextraction (HS–SPME) and analysed by Gas Chromatograp...
Introdução. Foxglove is the common name for the Digitalis genus members of the Plantaginaceae. Mo... more Introdução. Foxglove is the common name for the Digitalis genus members of the Plantaginaceae. Mostly known for being the source o f therapeutically important cardiac glycosides, several species are also of ornamental value. Digitalis mariana subsp. heywoodii (P.Silva & M.Silva) Hinz (= Digitalis purpurea subsp. heywoodii P.Silva & M.Silva) is endemic of the Iberian Peninsula and ha s a restricted habitat distribution [1]. Viewing to study cardenolide as well as non-cardeno lide compounds to access their bioactive properties, hairy root cultures from this rare species were obtained and their volatile composition was evaluated.
ABSTRACT: The antioxidant activities of the volatile and the nonvolatile fractions from Satureja... more ABSTRACT: The antioxidant activities of the volatile and the nonvolatile fractions from Satureja montana obtained by supercritical fluid extraction (SFE) and by conventional techniques, hydrodistillation (HD) and soxhlet extraction (SE), were compared. A good agreement between DPPH and rancimat methods was obtained showing that the extracts were able to scavenge free radicals and to inhibit lipid oxidation. The volatile oil (obtained by SFE at 90 bar/40 °C) was the most effective extract, presenting the lowest EC50 (0.06 g/L) and the highest protector factor (PF = 2.03). These results demonstrated the advantages of SFE over conventional techniques by avoiding thermodegradation and hydrolysis reactions. Furthermore, volatile oil is 15 times richer in thymoquinone than the essential oil (HD). This compound is of great importance due to its antioxidant, neuroprotective, and anti‐cancer activities. The combination of carvacrol + thymol + thymoquinone in volatile oil may be responsible ...
Goodyera macrophylla, considered a rare endemic, and Gennaria diphylla are two native terrestrial... more Goodyera macrophylla, considered a rare endemic, and Gennaria diphylla are two native terrestrial Orchidaceae species that can be found mainly in Madeiran Laurisilva. The volatile compounds contributing to the floral scent of these two Madeiran orchids were analysed and compared for the first time. The volatiles, isolated by distillation-extraction in a Likens-Nickerson-type apparatus, and those extracted by headspace sorption, were analysed by GC and GC-MS. The main volatile components isolated by distillation-extraction were γ-terpinene (13%) and n-nonanal (11%) in G. macrophylla and n-octacosane (19%) and n-heptacosane (13%) in G. diphylla. The main volatile components isolated by headspace sorption were p-cymene (21%), α-pinene (15%) and linalool (14%) in G. macrophylla and cis-arbusculone (28%) and lilac alcohol (26%) in G. diphylla. The importance of the volatiles in the pollination of these orchids is discussed.
Thyme is the common name of many taxa belonging to the Thymbra and Thymus genera. Given the econo... more Thyme is the common name of many taxa belonging to the Thymbra and Thymus genera. Given the economic importance of thyme oils, many thyme species have been studied and their essential oils and other volatile-containing extracts chemically characterized. Thymbra and Thymus species are frequent in the west Mediterranean region, considered to be the centre of origin of the genus Thymus, and extend further westwards in the Iberian Peninsula and northwest Africa, to the Macaronesian region in the Atlantic Ocean. The present work gives an overview of the chemical composition of the volatiles from the taxa of these two genera occurring in the above geographic area.
Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, w... more Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, were screened for their nematicidal activity against the pinewood nematode (PWN), Bursaphelenchus xylophilus. The essential oils were isolated by hydrodistillation and the volatiles by distillation-extraction, and both were analysed by GC and GC-MS. High nematicidal activity was achieved with essential oils from Chamaespartium tridentatum, Origanum vulgare, Satureja montana, Thymbra capitata, and Thymus caespititius. All of these essential oils had an estimated minimum inhibitory concentration ranging between 0.097 and 0.374 mg/ml and a lethal concentration necessary to kill 100% of the population (LC(100)) between 0.858 and 1.984 mg/ml. Good nematicidal activity was also obtained with the essential oil from Cymbopogon citratus. The dominant components of the effective oils were 1-octen-3-ol (9%), n-nonanal, and linalool (both 7%) in C. tridentatum, geranial (43%), neral (29%), and β-myrc...
With a characteristic flavour and aroma, “Maçã de Alcobaça” are apples produced in the western re... more With a characteristic flavour and aroma, “Maçã de Alcobaça” are apples produced in the western region of the mainland of Portugal. Given the known influence of pre-harvest cultural techniques and post-harvest conservation methods on fruit quality, this work evaluated the effect of cultural factors and conservation methods on the volatile profile of ‘Gala’ apples. Tests were carried out during four seasons (2018 to 2021) in two ‘Gala’ apple orchards (F and S) maintained with different irrigation rates and nitrogen fertilisation [normal irrigation and normal nitrogen (Control, NINN), normal irrigation and excess nitrogen (NIEN), excess irrigation and normal nitrogen (EINN), excess irrigation and excess nitrogen (EIEN)], and under three storage conditions [Controlled Atmosphere + 1-methylcyclopropene (CA+1-MCP), Dynamic Controlled Atmosphere (DCA) and DCA+1-MCP]. The intact fruit volatiles were isolated by headspace solid–phase microextraction (HS–SPME) and analysed by Gas Chromatograp...
Introdução. Foxglove is the common name for the Digitalis genus members of the Plantaginaceae. Mo... more Introdução. Foxglove is the common name for the Digitalis genus members of the Plantaginaceae. Mostly known for being the source o f therapeutically important cardiac glycosides, several species are also of ornamental value. Digitalis mariana subsp. heywoodii (P.Silva & M.Silva) Hinz (= Digitalis purpurea subsp. heywoodii P.Silva & M.Silva) is endemic of the Iberian Peninsula and ha s a restricted habitat distribution [1]. Viewing to study cardenolide as well as non-cardeno lide compounds to access their bioactive properties, hairy root cultures from this rare species were obtained and their volatile composition was evaluated.
ABSTRACT: The antioxidant activities of the volatile and the nonvolatile fractions from Satureja... more ABSTRACT: The antioxidant activities of the volatile and the nonvolatile fractions from Satureja montana obtained by supercritical fluid extraction (SFE) and by conventional techniques, hydrodistillation (HD) and soxhlet extraction (SE), were compared. A good agreement between DPPH and rancimat methods was obtained showing that the extracts were able to scavenge free radicals and to inhibit lipid oxidation. The volatile oil (obtained by SFE at 90 bar/40 °C) was the most effective extract, presenting the lowest EC50 (0.06 g/L) and the highest protector factor (PF = 2.03). These results demonstrated the advantages of SFE over conventional techniques by avoiding thermodegradation and hydrolysis reactions. Furthermore, volatile oil is 15 times richer in thymoquinone than the essential oil (HD). This compound is of great importance due to its antioxidant, neuroprotective, and anti‐cancer activities. The combination of carvacrol + thymol + thymoquinone in volatile oil may be responsible ...
Goodyera macrophylla, considered a rare endemic, and Gennaria diphylla are two native terrestrial... more Goodyera macrophylla, considered a rare endemic, and Gennaria diphylla are two native terrestrial Orchidaceae species that can be found mainly in Madeiran Laurisilva. The volatile compounds contributing to the floral scent of these two Madeiran orchids were analysed and compared for the first time. The volatiles, isolated by distillation-extraction in a Likens-Nickerson-type apparatus, and those extracted by headspace sorption, were analysed by GC and GC-MS. The main volatile components isolated by distillation-extraction were γ-terpinene (13%) and n-nonanal (11%) in G. macrophylla and n-octacosane (19%) and n-heptacosane (13%) in G. diphylla. The main volatile components isolated by headspace sorption were p-cymene (21%), α-pinene (15%) and linalool (14%) in G. macrophylla and cis-arbusculone (28%) and lilac alcohol (26%) in G. diphylla. The importance of the volatiles in the pollination of these orchids is discussed.
Thyme is the common name of many taxa belonging to the Thymbra and Thymus genera. Given the econo... more Thyme is the common name of many taxa belonging to the Thymbra and Thymus genera. Given the economic importance of thyme oils, many thyme species have been studied and their essential oils and other volatile-containing extracts chemically characterized. Thymbra and Thymus species are frequent in the west Mediterranean region, considered to be the centre of origin of the genus Thymus, and extend further westwards in the Iberian Peninsula and northwest Africa, to the Macaronesian region in the Atlantic Ocean. The present work gives an overview of the chemical composition of the volatiles from the taxa of these two genera occurring in the above geographic area.
Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, w... more Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, were screened for their nematicidal activity against the pinewood nematode (PWN), Bursaphelenchus xylophilus. The essential oils were isolated by hydrodistillation and the volatiles by distillation-extraction, and both were analysed by GC and GC-MS. High nematicidal activity was achieved with essential oils from Chamaespartium tridentatum, Origanum vulgare, Satureja montana, Thymbra capitata, and Thymus caespititius. All of these essential oils had an estimated minimum inhibitory concentration ranging between 0.097 and 0.374 mg/ml and a lethal concentration necessary to kill 100% of the population (LC(100)) between 0.858 and 1.984 mg/ml. Good nematicidal activity was also obtained with the essential oil from Cymbopogon citratus. The dominant components of the effective oils were 1-octen-3-ol (9%), n-nonanal, and linalool (both 7%) in C. tridentatum, geranial (43%), neral (29%), and β-myrc...
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Papers by José Barroso