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1.
J Agric Food Chem ; 69(15): 4550-4560, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33823588

RESUMEN

Coffee cupping includes both aroma and taste, and its evaluation considers several different attributes simultaneously to define flavor quality and therefore requires complementary data from aroma and taste. This study investigates the potential and limits of a data-driven approach to describe the sensory quality of coffee using complementary analytical techniques usually available in routine quality control laboratories. Coffee flavor chemical data from 155 samples were obtained by analyzing volatile (headspace-solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS)) and nonvolatile (liquid chromatography-ultraviolet/diode array detector (LC-UV/DAD)) fractions, as well as from sensory data. Chemometric tools were used to explore the data sets, select relevant features, predict sensory scores, and investigate the networks between features. A comparison of the Q model parameter and root-mean-squared error prediction (RMSEP) highlights the variable influence that the nonvolatile fraction has on prediction, showing that it has a higher impact on describing acid, bitter, and woody notes than on flowery and fruity. The data fusion emphasized the aroma contribution to driving sensory perceptions, although the correlative networks highlighted from the volatile and nonvolatile data deserve a thorough investigation to verify the potential of odor-taste integration.


Asunto(s)
Odorantes , Compuestos Orgánicos Volátiles , Café , Cromatografía de Gases y Espectrometría de Masas , Odorantes/análisis , Microextracción en Fase Sólida , Gusto , Compuestos Orgánicos Volátiles/análisis
2.
J Chromatogr A ; 1429: 329-39, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26733393

RESUMEN

Within a project exploring the application of lab-on-chip GC to in-field analysis of the plant volatile fraction, this study evaluated the performance of a set of planar columns (also known as microchannels, MEMS columns, or microfabricated columns) of different dimensions installed in a conventional GC unit. Circular double-spiral-shaped-channel planar columns with different square/rectangular sections up to 2m long were applied to the analysis of both essential oils and headspace samples of a group of medicinal and aromatic plants (chamomile, peppermint, sage, rosemary, lavender and bergamot) and of standard mixtures of related compounds; the results were compared to those obtained with reference narrow-bore columns (l:5m, dc:0.1mm, df:0.1 µm). The above essential oils and headspaces were first analyzed quali-and quantitatively with planar columns statically coated with conventional stationary phases (5%-phenyl-polymethylsiloxane and auto-bondable nitroterephthalic-acid-modified polyethylene glycol), and then submitted to chiral recognition of their diagnostic markers, by enantioselective GC with a planar columns coated with a cyclodextrin derivative (30% 6(I-VII)-O-TBDMS-3(I-VII)-O-ethyl-2(I-VII)-O-ethyl-ß-cyclodextrin in PS-086). Column characteristics and analysis conditions were first optimized to obtain suitable retention and efficiency for the samples investigated. The planar columns tested showed performances close to the reference conventional narrow-bore columns, with theoretical plate numbers per meter (N/m) ranging from 6100 to 7200 for those coated with the conventional stationary phases, and above 5600 for those with the chiral selector.


Asunto(s)
Cromatografía de Gases/instrumentación , Aceites Volátiles/química , Extractos Vegetales/química , Ciclodextrinas/química , Microtecnología , Aceites Volátiles/análisis , Extractos Vegetales/análisis , Aceites de Plantas/química , Siliconas/química , beta-Ciclodextrinas/química
3.
Animal ; 10(7): 1101-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26763800

RESUMEN

Echinacea pallida (EPAL), also known as pale purple coneflower, is a herbaceous flowering plant with immune-enhancement and antioxidative properties. The effect of EPAL on the reproductive performance, serum biochemistry and haematological parameters of rabbit does has been studied here. A total of 100, 21-week-old Grimaud rabbit does, were randomly assigned to two groups. One group was fed a basal diet supplemented with 3 g EPAL/kg diet (Echinacea group, E), while the other was fed the basal diet without the supplementation (control group, C). The reproductive performance of the does was not affected by the treatment (P>0.05). The haematological parameters of pregnant rabbits showed that there was no interaction between gestation day and treatment. The EPAL supplementation induced a reduction (-47.3%) in the basophil cell rate (0.55% and 0.29%, for the control and treatment groups, respectively; P=0.049). The gestation day significantly affected most of the haematological parameters (P<0.05). The white blood cell counts declined progressively after day 14. The mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, red cell distribution width, mean platelet volume and eosinophils increased steadily throughout the study, and reached a maximum value on day 28. The red blood cells, haemoglobin, haematocrit, mean corpuscular volume and neutrophils increased slightly up to day 14, and then subsequently decreased progressively until day 28. The lymphocytes and platelet distribution width decreased until day 14, and then increased to a maximum value on day 28. No significant effect of gestation day or treatment was observed on the blood serum chemistry. As far as the immune parameters are concerned, no significant differences were observed between groups, while a significant effect of gestation day was observed for lysozymes (6.02 v. 7.99 v. 1.91; for 0, 14 and 28 days, respectively; P=0.014). In conclusion, a lack of effect of EPAL has been observed. In fact, no impacts of EPAL have been observed on the reproductive or haematological parameters of the does. The effects of dietary supplementation with EPAL on the performances, bacterial community, blood parameters and immunity in growing rabbits are reported in the second part of this study.


Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Suplementos Dietéticos , Echinacea/química , Extractos Vegetales/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Antioxidantes/farmacología , Recuento de Eritrocitos/veterinaria , Femenino , Hematócrito , Pruebas Hematológicas , Hemoglobinas/análisis , Recuento de Leucocitos , Extractos Vegetales/química , Embarazo , Conejos , Reproducción/efectos de los fármacos
4.
Phytochem Anal ; 12(4): 255-62, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11705332

RESUMEN

Caper spurge (Euphorbia lathyris L.) seed oil contains a series of diterpenoids known as Euphorbia factors, or L-factors, L1-L9. They are esters of several polyols (lathyrol, epoxylathyrol, hydroxylathyrol and ingenol) and account for about 3-5% of the oil. The percentage of ingenol-based L-factors is very low, less than 5% of the diterpenoid fraction, but some of them (factors L5 and L6) are responsible for the irritant and co-carcinogenic activities of the oil. This paper reports an HPLC-UV and HPLC-positive-ESI-MS analysis of the diterpenoid fraction of caper spurge seed oil before and after selective hydrolysis of ingenol-based L-factors. Separation of lathyrane polyols and esters, and ingenol and its esters was achieved using a chromatographic system consisting of a C18 stationary phase and acetonitrile: water as mobile phase. A new macrocyclic constituent, the deoxy Euphorbia factor L1, was identified in the oil.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Diterpenos/análisis , Euphorbia/química , Fenilpropionatos/análisis , Aceites de Plantas/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrofotometría Ultravioleta/métodos , Sensibilidad y Especificidad
5.
Planta Med ; 67(3): 290-2, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11345708

RESUMEN

The volatile fraction of Tambourissa leptophylla fruit skin was extracted by petrol ether, purified by adsorption chromatography (LPC) and analysed by gas chromatographic-spectroscopic methods. 27 non-oxygenated terpene hydrocarbons and 10 oxygenated derivatives were identified. The most abundant components were: limonene (24.0%), cis-alpha-bergamotene (23.2%), delta-3-carene (8.2%), alpha-curcumene (6.0%), trans-alpha-bergamotene (5.1%), alpha-copaene (4.1%), alpha-pinene (4.0%), p-cymene (4.0%) and bicyclogermacrene (3.3%). The crude volatile fraction was tested in vitro against Cladosporium cucumerinum in direct bioautography on TLC plates on the basis of the antifungal use of fruit skin. Activity of petrol ether extract against this micro-organism was demonstrated.


Asunto(s)
Frutas/química , Lauraceae/química , Terpenos/aislamiento & purificación , Antifúngicos/farmacología , Cromatografía en Capa Delgada , Cladosporium/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Plantas Medicinales/química , Terpenos/química , Terpenos/farmacología , Volatilización
6.
J Chromatogr A ; 892(1-2): 469-85, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11045505

RESUMEN

Solid-phase microextraction (SPME) is a solvent-free technique, which is well established in headspace analysis since it is sensitive, because of the concentration factor achieved by the fibres, and selective, because of different coating materials which can be used. The performance of eight commercially available SPME fibres was compared to evaluate the recoveries of some characteristic components with different polarities and structures present in the headspace of four aromatic and medicinal plants: rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), thyme (Thymus vulgaris L.) and valerian (Valeriana officinalis L.). The relative concentration capacity of each fibre on the same components of each plant was also determined by comparing their abundance with that obtained by classical static-headspace GC. The partition coefficient, K1, between the headspace gaseous phase and SPME polymeric coating, and the relative concentration factors, of some of the characteristic components of the plant investigated dissolved in dibutyl phtalate, were also determined, under rigorously standardised analysis conditions. The results showed that the most effective fibres were those consisting of two components, i.e., a liquid phase (polydimethylsiloxane) and a porous solid (carboxen or divinylbenzene, or both).


Asunto(s)
Cromatografía de Gases/métodos , Plantas Medicinales/química , Volatilización
7.
Mutat Res ; 281(2): 143-7, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1370983

RESUMEN

The mutagenicity of a series of pyrrolizidine alkaloids, and of extracts from several Italian Senecio species containing pyrrolizidine alkaloids, including S. inaequidens, S. fuchsii and S. cacaliaster, were tested using the Salmonella typhimurium/mammalian microsome system. Retrorsine, senecivernine, seneciphylline and the Senecio extracts showed a weakly mutagenic activity.


Asunto(s)
Mutágenos/toxicidad , Extractos Vegetales/toxicidad , Plantas Tóxicas , Alcaloides de Pirrolicidina/toxicidad , Senecio/química , Animales , Relación Dosis-Respuesta a Droga , Técnicas In Vitro , Microsomas Hepáticos/metabolismo , Pruebas de Mutagenicidad , Ratas , Ratas Endogámicas , Salmonella typhimurium/efectos de los fármacos
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