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1.
Food Chem ; 221: 169-177, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979148

RESUMO

The main goal of the present study was to describe the volatile profile of three different basil genotypes (Genovese and Green and Purple Iranian), and the impact that water stress (75% and 50% field capacity) and storage time (up to 7days) have under mild refrigerated conditions. The chromatographic profile pointed to three different chemotypes: linalool/eugenol, neral/geranial, and estragol, for Genovese, Green, and Purple genotypes, respectively. Water stress depleted the volatile profile of these three landraces, due to a reduction in the absolute concentrations of some of the components related to fresh aroma (linalool, nerol, geraniol and eugenol). The stability of the basil volatile profile during storage varied depending on the water stress that had been applied. Concentration reductions of close to 50% were quantified for most of the components identified in the Purple genotype.


Assuntos
Dessecação , Manipulação de Alimentos , Conservação de Alimentos , Ocimum basilicum/química , Compostos Orgânicos Voláteis/análise , Monoterpenos Acíclicos , Derivados de Alilbenzenos , Anisóis/análise , Eugenol/análise , Análise de Alimentos , Qualidade dos Alimentos , Armazenamento de Alimentos , Genótipo , Irã (Geográfico) , Monoterpenos/análise , Ocimum basilicum/classificação , Terpenos/análise
2.
Plant Foods Hum Nutr ; 70(1): 15-20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25645661

RESUMO

Changes in the contents and composition of polyphenolics and resulting antioxidant activities of S. verbenaca by-products were investigated at three phenological stages (flowering, early fruiting and late fruiting stages). The highest accumulation of total phenolics was detected at the flowering stage (58.36 mg GAE/g DW). HPLC analysis of methanolic extracts showed the prevalence of methyl carnosate (821.45-919.82 µg/g DW) and rosmarinic acid (544.51-649.26 µg/g DW). Phenolic diterpenes (1056.90-1148.42 µg/g DW) was the most represented class of compounds. Three complementary tests namely, DPPH(•) (IC50 value, 49.22 µg/mL) and ABTS(•+)-radical scavenging assays (146.86 µM TE/mg) and FRAP reducing power test (188.93 mM Fe(II)/mg) were used to evaluate the antioxidant capacity and showed the best performance at the early fruiting period. The current study evidenced the significant effect of phenophase on antioxidants and contributed to valorize S. verbenaca extracts as a source of functional phenolic compounds.


Assuntos
Antioxidantes/química , Flores/química , Frutas/química , Extratos Vegetais/farmacologia , Salvia/química , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Depsídeos/análise , Diterpenos/análise , Fenóis/análise , Relação Estrutura-Atividade , Ácido Rosmarínico
3.
Food Chem ; 151: 212-8, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24423523

RESUMO

The aim of the present work was to evaluate whether the relation between the concentrations of the two major diterpenes present in two typified rosemary extracts affects their levels of deposition and antioxidant capacity in different lamb tissues. The composition of the extracts expressed as percentage of weight/weight was 1:1 (14-16)% and 2:1 (25-11)% (carnosic acid-carnosol), respectively. Thirty weaned lambs were assigned randomly to three homogeneous groups. One group was fed a basal diet as a control and the diets of the other two were enriched with rosemary extracts 1:1 and 2:1, respectively. HPLC-ESI-MS/TOF identified a metabolite (C19H22O3) described for the first time in lamb tissues, along with carnosol, carnosic acid, rosmanol and carnosol-p-quinone. The results obtained corroborate the importance of the presence of carnosol in the dietary administration of rosemary extract as a way of improving the stability of the diterpene fraction during feed manufacturing and the level of deposition and antioxidant efficacy of diterpenes after ruminal fermentation.


Assuntos
Abietanos/química , Carne/análise , Rosmarinus/química , Animais , Antioxidantes , Dieta , Ovinos , Especiarias
4.
J Agric Food Chem ; 60(38): 9603-8, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22957812

RESUMO

The importance of the diterpenic and rosmarinic acid content in the biological activities of rosemary extracts has been studied previously, but how the relationship between the concentration of these components affects their antioxidant and antibacterial activities has received little attention. Accordingly, from a total of 150 plants, 27 methanolic extracts were selected, for their similar diterpene contents but different ratios between carnosic acid and carnosol concentrations. In extracts with similar rosmarinic acid contents but differing proportions between carnosic acid and carnosol, the two diterpenes were seen to equally affect the in vitro antioxidant activity; however, and related with the antibacterial efficiency, this biological activity improved when carnosol was the major diterpene component.


Assuntos
Abietanos/farmacologia , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rosmarinus/química , Abietanos/análise , Antibacterianos/química , Antioxidantes/química , Cinamatos/análise , Depsídeos/análise , Listeria monocytogenes/efeitos dos fármacos , Metanol , Extratos Vegetais/análise , Staphylococcus aureus/efeitos dos fármacos , Ácido Rosmarínico
5.
Nat Prod Commun ; 5(4): 629-34, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20433087

RESUMO

Satureja x delpozoi is a hybrid found in south-eastern Spain, in a population in which both parents S. intrincata and S. obovata are found together. This work presents for the first time the volatile profile and antioxidant activity of the essential oils of this hybrid. The volatile profile of the essential oils from S. x delpozoi underlines the hybrid character of these plants since the p-cymene, gamma-terpinene, camphor and thymol concentrations in hybrid 1, and the same components, along with alpha-terpineol concentrations in hybrid 2, showed intermediate values with respect to the values observed in the parents. As regards the antioxidant capacity, the phenolic content of S. intrincata resulted in its essential oil having the greatest activity against the DPPH* and ABTS*+ radicals. Both hybrids showed low activity against these radicals, although S. obovata showed none. On the bases of their essential oil composition and antioxidant capacity, these results corroborate the hybrid character of these two S. x delpozoi plants.


Assuntos
Sequestradores de Radicais Livres/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Satureja/química , Benzotiazóis , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/isolamento & purificação , Picratos/química , Folhas de Planta/química , Óleos de Plantas/isolamento & purificação , Caules de Planta/química , Espanha , Ácidos Sulfônicos/química , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/farmacologia , Tiazóis/química
6.
J Agric Food Chem ; 57(21): 10349-56, 2009 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-19886685

RESUMO

The variation in the chemical composition of the essential oil of Salvia officinalis , growing in different habitats, was studied. GC-MS analysis revealed 57 compounds representing 94.68-96.80% of total oils. The major components were alpha-thujone (11.55-19.23%), viridiflorol (9.94-19.46%), 1,8-cineole (8.85-15.60%), camphor (5.08-15.06%), manool (5.52-13.06%), beta-caryophyllene (2.63-9.24%), alpha-humulene (1.93-8.94%), and beta-thujone (5.45-6.17%), showing significant differences between different collection sites. Analysis of some representative polyphenolic compounds and antioxidant activity was performed using postdistilled dry samples. Rosmarinic acid, carnosol, and carnosic acid were the prevalent compounds of S. officinalis methanolic extracts. The results revealed differences in the polyphenolic composition and also exhibited antioxidant and radical-scavenging activities at different magnitudes of potency. However, within the used methods, only the DPPH(*) assay showed significant differences (p < 0.05) in free radical scavenging activity among samples collected in different regions. Plants collected in the coastal regions Soliman and Kelibia accumulate more polyphenolic compounds, known to be responsible for the main antioxidant activity of sage (rosmarinic acid, carnosol, and carnosic acid), than those growing inland at Bou Arada and Sers. Moreover, the former presented a higher radical-scavenging activity. The methanolic extracts of postdistilled S. officinalis might be valuable antioxidant natural sources and seemed to be applicable in both the health medicine and food industries.


Assuntos
Antioxidantes/análise , Óleos Voláteis/análise , Fenóis/análise , Óleos de Plantas/análise , Salvia officinalis/química , Tunísia
7.
J Agric Food Chem ; 56(9): 3363-7, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-18422334

RESUMO

The aim of the present work is to study whether the introduction of rosemary plant byproduct, from plant steam distillation, in daily Segurena sheep feeding allows the transfer of active antioxidant components to lamb meat, without detriment to the animal productivity. For this, 36 Segurena ewes were assigned randomly to three homogeneous groups. One group was fed a basal diet as a control and the diet of the other two groups was modified by substituting 10 or 20% of the control diet (respectively) with distilled rosemary leaves. Chromatographic analysis allowed the identification of 11 polyphenolic components previously identified in the rosemary and basal diet pellets, respectively. Among them, rosmarinic acid, carnosol, and carnosic acid were the phenolic components that had a significantly increased presence ( P < 0.05) in the lamb meat from sheep mothers fed this aromatic herb, when compared to the control group. The incorporation of this byproduct into the animal diet favored the antioxidant capacity of these lamb meat samples. Fresh meat produced on rosemary had higher total ferric reducing antioxidant power (FRAP) ( P < 0.05), greater ability to reduce ABTS*+, and lower IC50 (DPPH*) ( P < 0.05) values when compared to the control group. Because no statistically significant differences were detected among the results obtained from the lamb meat belonging to the different ewe groups fed rosemary leaf extract (10 or 20%), it can be concluded that the incorporation of distilled rosemary leaves at a rate of 10% of the ewes' diet should be enough to improve the lamb meat antioxidant status.


Assuntos
Dieta , Flavonoides/análise , Carne/análise , Fenóis/análise , Folhas de Planta/química , Rosmarinus/química , Ovinos/metabolismo , Animais , Antioxidantes/análise , Suplementos Nutricionais , Feminino , Flavonoides/metabolismo , Fenóis/metabolismo , Polifenóis
8.
J Agric Food Chem ; 52(17): 5418-24, 2004 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-15315379

RESUMO

Thymus zygis subsp. gracilis (chemotype thymol) was evaluated on the basis of its phytomass production and essential oil quality. Three different watering levels were assayed to achieve 63, 44, and 30% of the local potential evapotranspiration (Eto). According to the statistical analysis, a water supplement equivalent to 44% Eto in this cultivation area was optimal for maximum plant dry matter production and essential oil yield. Capillary GC-MS analysis of the essential oil allowed the identification of 86 volatile components. Among them, 30 are described for the first time as volatile constituents of the essential oil in this thyme subspecies and chemotype. The watering level effect on essential oil composition was noticeable, because the application of a water supplement equivalent to the 63% Eto favored the production of an essential oil richer in low molecular weight components. However, the greatest thymol concentrations were obtained under the 30 and 44% Eto watering levels.


Assuntos
Lamiaceae/química , Lamiaceae/crescimento & desenvolvimento , Óleos Voláteis/química , Água/administração & dosagem , Cromatografia Gasosa-Espectrometria de Massas , Fenóis/análise , Óleos de Plantas/química , Volatilização
9.
J Agric Food Chem ; 51(18): 5420-7, 2003 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-12926892

RESUMO

Thymus hyemalis Lange (chemotype thymol) was cultivated as an experimental crop under different watering level conditions in order to achieve 80, 60, 40, and 20% of the local potential evapotranspiration (Eto). Two harvesting periods were considered, winter and spring. As a consequence of the great variability among plants, essential oil yield percentages did not show statistically significant differences among seasons and different levels of water supply. Capillary GC-MS analysis of the essential oils permitted the detection of 84 volatile components. Among them, 54 are described for the first time as volatile constituents of the chromatographic profile of this Thymus species. Winter harvesting showed high concentrations in thymol percentage (25.92 +/- 4.39), the 40% Eto watering level being the best with respect to obtaining the optimum quality of this essential oil. However, in spring this thyme species needs a greater water supply (80% Eto) to achieve the same amount of thymol in the essential oil (29.20 +/- 2.83). From this, it was concluded that winter harvesting could be used for the extraction of the essential oil, with a low level of water supply, whereas spring harvesting could be employed for collection of leaves as a food condiment.


Assuntos
Lamiaceae/química , Lamiaceae/crescimento & desenvolvimento , Óleos Voláteis/análise , Óleos Voláteis/química , Água , Cromatografia Gasosa-Espectrometria de Massas , Estações do Ano , Timol/análise , Thymus (Planta)/química , Thymus (Planta)/crescimento & desenvolvimento
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