Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 27
Filter
Add more filters










Publication year range
1.
Nat Prod Res ; : 1-6, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37904525

ABSTRACT

Pecan nuts (Carya illinoinensis (Wangenh.) K. Koch) contain the highest number of phytochemicals of all nuts, are a natural source of unsaturated fatty acids and other nutrients and can be considered an important addition to the Mediterranean diet al.though several studies have been carried out on pecans, employing several analytical techniques, no systematic study of the metabolic profile is available in literature. In this study, the metabolic profile of pecan nuts of three different cultivars was analysed by Nuclear Magnetic Resonance Spectroscopy. The cultivars compared were Wichita, Stuart, and Sioux, all grown in Italy in the same pedoclimatic conditions. 31 metabolites were identified and 28 were quantified and the three species were differentiated based on multivariate PCA analysis. The differences among them, and the levels of scutellarein and GABA, in particular, were attributed to the adaptation of the plants to the climate in their original areas.

2.
Foods ; 12(10)2023 May 11.
Article in English | MEDLINE | ID: mdl-37238768

ABSTRACT

'Tonda Gentile Romana' and 'Tonda di Giffoni' (Corylus avellana L.) are two Italian hazelnut cultivars, recognized under the quality labels "Protected Designation of Origin" (PDO) and "Protected Geographical Indication" (PGI), respectively. Hazelnut seeds are characterized by a complex microstructure and the presence of different physical compartments. This peculiarity has been studied and evidenced by Time Domain (TD) Nuclear Magnetic Resonance (NMR) experiments. This technique allowed the assessment of the presence of different diffusion compartments, or domains, by evaluating the distribution of the spin-spin relaxation time (T2).The aim of this research was to develop a method based on 1H NMR relaxometry to study the mobility in fresh hazelnut seeds ('Tonda di Giffoni' and 'Tonda Gentile Romana'), in order to determine differences in seed structure and matrix mobility between the two cultivars. TD-NMR measurements were performed from 8 to 55 °C in order to mimic post-harvest processing as well the microscopic textural properties of hazelnut. The Carr-Purcell-Meiboom-Gill (CPMG) experiments showed five components for 'Tonda Gentile Romana' and four components for 'Tonda di Giffoni' relaxation times. The two slowest components of relaxation (T2,a about 30-40% of the NMR signal, and T2,b about 50% of the NMR signal) were attributed to the protons of the lipid molecules organized in the organelles (oleosomes), both for the 'Tonda Gentile Romana' and for the 'Tonda di Giffoni' samples. The component of relaxation T2,c was assigned to cytoplasmic water molecules, and showed a T2 value dominated by diffusive exchange with a reduced value compared to that of pure water at the same temperature. This can be attributed to the water molecules affected by the relaxation effect of the cell walls. The experiments carried out as a function of temperature showed, for 'Tonda Gentile Romana', an unexpected trend between 30 and 45 °C, indicating a phase transition in its oil component. This study provides information that could be used to strengthen the specifications underlying the definitions of "Protected Designation of Origin" (PDO) and "Protected Geographical Indication" (PGI).

3.
Front Mol Biosci ; 8: 688440, 2021.
Article in English | MEDLINE | ID: mdl-34671642

ABSTRACT

The development of the human gut microbiota is characterized by a dynamic sequence of events from birth to adulthood, which make the gut microbiota unique for everyone. Its composition and metabolism may play a critical role in the intestinal homeostasis and health. We propose a study on a single mother-infant dyad to follow the dynamics of an infant fecal microbiota and metabolome changes in relation to breast milk composition during the lactation period and evaluate the changes induced by introduction of complementary food during the weaning period. Nuclear Magnetic Resonance (NMR)-based metabolomics was performed on breast milk and, together with 16S RNA targeted-metagenomics analysis, also on infant stool samples of a mother-infant dyad collected over a period running from the exclusive breastfeeding diet to weaning. Breast milk samples and neonatal stool samples were collected from the 4th to the 10th month of life. Both specimens were collected from day 103 to day 175, while from day 219-268 only stool samples were examined. An exploratory and a predictive analysis were carried out by means of Common component and specific weight analysis and multi-block partial least squares discriminant analysis, respectively. Stools collected during breastfeeding and during a mixed fruit/breastfeeding diet were characterized by high levels of fucosyl-oligosaccharides and glycolysis intermediates, including succinate and formate. The transition to a semi-solid food diet was characterized by several changes in fecal parameters: increase in short-chain fatty acids (SCFAs) levels, including acetate, propionate and butyrate, dissapearance of HMOs and the shift in the community composition, mainly occurring within the Firmicutes phylum. The variations in the fecal metabolome reflected the infant's diet transition, while the composition of the microbiota followed a more complex and still unstable behavior.

4.
Nat Prod Res ; 35(21): 3839-3849, 2021 Nov.
Article in English | MEDLINE | ID: mdl-32233655

ABSTRACT

In this work, the first phytochemical analysis ever performed on the unripe female cones of Wollemia nobilis W. G. Jones, K. D. Hill & J. M. Allen was described. The analysis evidenced the presence of a new derivative of sandaracopimaric acid together with rare diterpenoid derivatives and known compounds of chemosystematic and bioactivity relevance. Some of these were evidenced in the species or in the family for the first time during this study. The further implications of the isolated compounds in the field of chemosystematics, pharmacology and nutraceutics were discussed.


Subject(s)
Diterpenes , Tracheophyta , Phytochemicals
5.
Molecules ; 25(14)2020 Jul 09.
Article in English | MEDLINE | ID: mdl-32660058

ABSTRACT

The rationale inspiring the discovery of lead compounds for the treatment of human parasitic protozoan diseases from natural sources is the well-established use of medicinal plants in various systems of traditional medicine. On this basis, we decided to select an overlooked medicinal plant growing in central Italy, Marrubium incanum Desr. (Lamiaceae), which has been used as a traditional remedy against protozoan diseases, and to investigate its potential against Human African trypanosomiasis (HAT). For this purpose, we assayed three extracts of different polarities obtained from the aerial parts of M. incanum-namely, water (MarrInc-H2O), ethanol (MarrInc-EtOH) and dichloromethane (MarrInc-CH2Cl2)-against Trypanosoma brucei (TC221), with the aim to discover lead compounds for the development of antitrypanosomal drugs. Their selectivity index (SI) was determined on mammalian cells (BALB/3T3 mouse fibroblasts) as a counter-screen for toxicity. The preliminary screening selected the MarrInc-CH2Cl2 extract as the most promising candidate against HAT, showing an IC50 value of 28 µg/mL. On this basis, column chromatography coupled with the NMR spectroscopy of a MarrInc-CH2Cl2 extract led to the isolation and identification of five compounds i.e. 1-α-linolenoyl-2-palmitoyl-3-stearoyl-sn- glycerol (1), 1-linoleoyl-2-palmitoyl-3-stearoyl-sn-glycerol (2), stigmasterol (3), palmitic acid (4), and salvigenin (5). Notably, compounds 3 and 5 were tested on T. brucei, with the latter being five-fold more active than the MarrInc-CH2Cl2 extract (IC50 = 5.41 ± 0.85 and 28 ± 1.4 µg/mL, respectively). Furthermore, the SI for salvigenin was >18.5, showing a preferential effect on target cells compared with the dichloromethane extract (>3.6). Conversely, stigmasterol was found to be inactive. To complete the work, also the more polar MarrInc-EtOH extract was analyzed, giving evidence for the presence of 2″-O-allopyranosyl-cosmosiin (6), verbascoside (7), and samioside (8). Our findings shed light on the phytochemistry of this overlooked species and its antiprotozoal potential, providing evidence for the promising role of flavonoids such as salvigenin for the treatment of protozoal diseases.


Subject(s)
Marrubium/chemistry , Plant Extracts/chemistry , Trypanocidal Agents , Trypanosoma brucei brucei/growth & development , 3T3 Cells , Animals , Humans , Mice , Trypanocidal Agents/chemistry , Trypanocidal Agents/isolation & purification , Trypanocidal Agents/pharmacology
6.
Foods ; 9(7)2020 Jul 17.
Article in English | MEDLINE | ID: mdl-32708866

ABSTRACT

Brassicaceae family provides several crops which are worldwide known for their interesting phytochemical profiles, especially in terms of content of glucosinolates. These secondary metabolites show several beneficial effects toward consumers' health, and several studies have been conducted to identify cultivation factors affecting their content in crops. One of the agronomic practices which is attracting growing interest is the organic one, which consists in avoiding the use of mineral fertilizers as well as pesticides. The aim of this study is to define the metabolic profile of Brassica oleracea (var. italica) and to compare the samples grown using organic and conventional fertilization methods. The hydroalcoholic and organic extracts of the samples have been analyzed by NMR spectroscopy. Forty-seven metabolites belonging to the categories of organic acids, amino acids, carbohydrates, fatty acids, sterols, and other molecules have been identified. Thirty-seven metabolites have been quantified. Univariate and multivariate PCA analyses allowed to observe that the organic practice influenced the nitrogen transport, the carbohydrate metabolism, the glucosinolate content and the phenylpropanoid pathway in B. oleracea (var. italica).

7.
Pharmaceuticals (Basel) ; 13(5)2020 May 14.
Article in English | MEDLINE | ID: mdl-32423026

ABSTRACT

The winemaking process produces a huge number of pomaces that generally are used for energy purposes. Further valuable applications such as health-promoting properties are still under investigation. The seeds of the white berries of Mantonico and Pecorello cv. were extracted in a Soxhlet apparatus, using n-hexane and chloroform as solvents. Extracts were characterized by NMR and GC-MS analyses. They were assayed in vitro as wound healing and anti-inflammatory agents in HaCaT and RAW 264.7 cell lines, respectively. n-hexane Mantonico extract resulted in the most interesting wound healing sample, while n-hexane Pecorello, containing a good number of carotenoids, resulted in a good anti-inflammatory candidate. These preliminary findings underlined the benefit of grape seed extracts valorization due to their health-promoting properties.

8.
Pharmaceuticals (Basel) ; 13(5)2020 May 03.
Article in English | MEDLINE | ID: mdl-32375256

ABSTRACT

Several epidemiological studies demonstrate that moderate (red) wine consumption may afford protection against cardiovascular diseases. Protection is ascribed to the biological activity of wine components, many of which, however, are discarded during winemaking. In vitro rat thoracic aorta rings contracted with phenylephrine or KCl were used to assess the vasorelaxant activity of extracts from wine pomaces (seeds and skins) of the Calabrian autochthonous grape variety Magliocco dolce (Arvino). NMR spectroscopy was used to ascertain their chemical composition. Data demonstrate that seed and skin, but not must, extracts are capable of relaxing vascular preparations in an endothelium-dependent manner, similarly to the red wine extract, due to the presence of comparable amounts of bioactive constituents. In rings pre-contracted with 20-30 mM KCl, only seed extracts showed a moderate relaxation. The most efficacious vasodilating extract (wine) showed a good antioxidant profile in both [(2,2-diphenyl-1-picrylhydrazyl)acid] radical (DPPH) and [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)] radical (ABTS) assays. In conclusion, winemaking from Magliocco dolce grape can provide potentially health-promoting by-products useful in cardiovascular disease management.

9.
Foods ; 9(4)2020 Apr 11.
Article in English | MEDLINE | ID: mdl-32290387

ABSTRACT

The water-holding capacity (WHC) is among the key factors in determining the quality of meat and its value, which is strongly influenced by the content and quality of the connective tissue proteins like collagen. Therefore, the factors that influence the proteins' stability, e.g., pH, ionic strength, and the antioxidants which are used to increase the meat shelf-life, also affect the WHC. The interaction of collagen, whose structure is strongly influenced by the interaction with water molecules, can be studied following the behavior of water diffusion by low-resolution 1H NMR experiments. The present study is addressed to study the collagen stability as a function of pH, ionic strength, and phenolic antioxidants like catechin. The experimental study demonstrated how the 1H NMR time domain (TD) experiments are able to evaluate the hydration properties of collagen, not only as a function of ionic strength and pH, but also in determining the ability of catechin to interact both on the surface of the collagen fibrils and inside the fibrillar domain.

10.
Antioxidants (Basel) ; 9(1)2020 Jan 08.
Article in English | MEDLINE | ID: mdl-31936207

ABSTRACT

Inflammatory bowel disease and food allergies are a growing topic in the field of nutrition science. Polyphenols, which are the most important secondary metabolites of plants, demonstrated to modulate the expression and/or production of numerous proteins, but also to regulate the intestinal ecosystem. In this context, our aim was the investigation of protective effects against the gastrointestinal mucosa of fortified milk kefir obtained by adding seeds extract from Sangiovese cv. Pomace. Methods: An ultrasound-assisted method was used to obtain the extracts. All the extracts were assayed for the antioxidant activity. The best extract was used as an additive of fermented milk kefir to obtain a fortified final product. Kefir samples were analyzed by NMR spectroscopy. The efficiency of the barrier functions was evaluated by measuring trans-epithelial electric resistance (TEER) using a voltmeter. Results: the enriched kefir (Ksgn) possesses higher antioxidant performances compared to the unfortified sample (Kwht). Kwht and Ksgn did not alter Caco-2 TEER in basal condition.

11.
Nat Prod Res ; 34(14): 2043-2050, 2020 Jul.
Article in English | MEDLINE | ID: mdl-30810363

ABSTRACT

Bacterial canker of Actinidia, caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa), is the most serious disease of these plants worldwide. Leaves of three species of Actinidia, namely A. chinensis var. chinensis, A. chinensis var. deliciosa and A. arguta, having different degrees of tolerance to Psa, were analyzed by Nuclear Magnetic Resonance spectroscopy. Aqueous extracts of leaves were studied and several metabolites, classified as organic acids, amino acids, carbohydrates, phenols and other metabolites, were identified by 1D and 2D NMR experiments and quantified. The metabolic profiles of these species were compared through univariate statistical analysis ANOVA and multivariate PCA. Levels of metabolites with known antibacterial activity, such as caffeic and chlorogenic acids, were observed to be higher in the A. arguta samples. Moreover, these metabolites have different Pearson correlation patterns among the three Actinidia species, suggesting a difference at the phenylpropanoid biosynthetic pathway.


Subject(s)
Actinidia/microbiology , Plant Leaves/microbiology , Pseudomonas syringae/pathogenicity , Anti-Bacterial Agents , Magnetic Resonance Spectroscopy , Plant Diseases/microbiology , Plant Extracts/metabolism , Plant Leaves/metabolism , Species Specificity
12.
Nat Prod Res ; 34(1): 53-62, 2020 Jan.
Article in English | MEDLINE | ID: mdl-30821504

ABSTRACT

The study focuses on the understanding, at molecular level, the mechanism of interaction between protein and flavonoids. Collagen and catechin interactions were investigated by NMR in solution and solid state. The effect of catechin on the stability of collagen to oxidation was also explored. Collagen was treated with two concentrations of catechin solutions. Oxidation was carried out by incubation of collagen solution with three oxidation systems: Fe(II)/H2O2, Cu(II)/H2O2, and NaOCl/H2O2. The effects of oxidation systems were evaluated by high resolution 1 D and 2 D proton spectroscopy and solid state NMR (13C CP MAS) experiments. Interactions between collagen and catechin preferentially occur between catechin B ring and the amino acids Pro and Hyp of collagen. Results showed that both iron and copper oxidation systems were able to interact with collagen by site specific attack. Moreover, catechin protects collagen proline from oxidation by metal/H2O2 systems, preventing copper and iron approach to collagene molecule;this behaviour was more evident for the copper/H2O2 system.


Subject(s)
Catechin/metabolism , Collagen Type I/metabolism , Hydrogen Peroxide/chemistry , Binding Sites , Catechin/chemistry , Catechin/pharmacology , Collagen Type I/chemistry , Flavonoids/chemistry , Flavonoids/metabolism , Magnetic Resonance Spectroscopy/methods , Metals/chemistry , Oxidation-Reduction , Protein Stability/drug effects , Proteins/chemistry , Proteins/metabolism
13.
Phytochemistry ; 158: 91-95, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30481664

ABSTRACT

An undescribed labdane-like diterpene with a rare spiro-ß-lactone function was identified from the ethanol extract of the male cones of the coniferous tree Wollemia nobilis. This spirolabdadienolide (IUPAC name: syn-ent-8(17),13-labdadien-19,18-olid-15-oic acid methyl ester; trivial name: wollemolide), was isolated by means of traditional and high performance chromatography techniques and structurally elucidated through NMR and MS. In addition, six further known metabolites were evidenced in the extract. Wollemolide, which may be considered an additional chemotaxonomic marker, and 4'-O-methyl-scutellarein, a simple flavonoid, had not been isolated in our previous phytochemical study on the same plant organ. This demonstrates how the molecular pattern of a plant species is in continuous movement and changes with the passing of time according to the climate of the year.


Subject(s)
Diterpenes/analysis , Flavonoids/analysis , Spiro Compounds/analysis , Tracheophyta/chemistry , Tracheophyta/metabolism , Diterpenes/chemistry , Flavonoids/chemistry , Fruit/chemistry , Fruit/metabolism , Italy , Lactones/analysis , Lactones/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Seasons , Spectrometry, Mass, Electrospray Ionization , Spiro Compounds/chemistry
14.
J Pharm Biomed Anal ; 160: 152-159, 2018 Oct 25.
Article in English | MEDLINE | ID: mdl-30086508

ABSTRACT

In this work, the phytochemical profile of the ethanolic extract of Euphorbia peplus L. collected in Central Italy, was reported. This specimen had never been studied before and the analysis was accomplished by means of Column Chromatography for the separation procedure and by means of NMR Spectroscopy and Mass Spectrometry for the identification step. In particular, fourteen compounds were evidenced belonging to five different classes of natural compounds i.e. triterpenoids (pentacyclic and saponin), peculiar diterpenoids (jatrophanes and pepluanes), flavonoids (flavonols), caffeoyl-quinic acids and rare disaccharides. In addition to this, a semi-quantitative analysis on the diterpenoid fraction, by means of NMR Spectroscopy, was also performed in order to provide the real quantities of these compounds in the same fraction and in the total extract. Due to the pronounced chemo variability observed in Euphorbia spp., the availability of a reliable and quick analytical technique, such as that reported in the present study, could be a useful tool in the standardization of plant materials to be used in pharmacological studies or for ethnomedicinal purposes. The technical details for both the general phytochemical analysis and the specific quantitative one, were inserted in this paper. Moreover, the chemotaxonomic and ethnopharmacological relevance of these compounds was also discussed.


Subject(s)
Diterpenes/analysis , Euphorbia/chemistry , Phytochemicals/analysis , Diterpenes/chemistry , Ethnopharmacology , Italy , Magnetic Resonance Spectroscopy , Phytochemicals/chemistry
15.
Nat Prod Res ; 31(7): 765-772, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27712103

ABSTRACT

The metabolic profiling of pistachio (Pistacia vera) aqueous extracts from two different cultivars, namely 'Bianca' and 'Gloria', was monitored over the months from May to September employing high field NMR spectroscopy. A large number of water-soluble metabolites were assigned by means of 1D and 2D NMR experiments. The change in the metabolic profiles monitored over time allowed the pistachio development to be investigated. Specific temporal trends of amino acids, sugars, organic acids and other metabolites were observed and analysed by multivariate Partial Least Squares (PLS) analysis. Statistical analysis showed that while in the period from May to September there were few differences between the two cultivars, the ripening rate was different.


Subject(s)
Magnetic Resonance Spectroscopy/methods , Metabolome/physiology , Pistacia/physiology , Amino Acids/analysis , Carbohydrate Metabolism , Carbohydrates/analysis , Metabolomics/methods , Monitoring, Physiologic/methods , Pistacia/chemistry
16.
J Agric Food Chem ; 64(25): 5284-91, 2016 Jun 29.
Article in English | MEDLINE | ID: mdl-27281439

ABSTRACT

Carrots are usually consumed in their native form or processed into many different products. Carrot juice is a popular beverage consumed throughout the world and is attracting increasing attention due to its nutritional value, being a natural source of bioactive compounds. Ready-to-drink carrot juices produced in the same factory were analyzed by (1)H nuclear magnetic resonance (NMR) spectroscopy. The juices were made from carrot roots of the same cultivar grown in three different geographical areas in Italy. More than 30 compounds have been identified and quantified, and the data was subjected to univariate ANOVA and multivariate analyses. Clear geographical-dependent clustering was observed, and the metabolic profiles were related to the different pedoclimatic conditions. The proposed phytoprofiling approach could be employed on an industrial scale to evaluate finished products involving different sites of supply of the raw material, thus improving both the quality and uniformity of the juices.


Subject(s)
Daucus carota/chemistry , Fruit and Vegetable Juices/analysis , Magnetic Resonance Spectroscopy/methods , Metabolomics/methods , Food Handling , Italy , Quality Control
17.
Plant Cell Rep ; 35(5): 1009-20, 2016 May.
Article in English | MEDLINE | ID: mdl-26795145

ABSTRACT

KEY MESSAGE: Acetic acid acts as a signal molecule, strongly enhancing xanthone biosynthesis in Hypericum perforatum root cultures. This activity is specific, as demonstrated by the comparison with other short-chain monocarboxylic acids. We have recently demonstrated that Hypericum perforatum root cultures constitutively produce xanthones at higher levels than the root of the plant and that they respond to chitosan (CHIT) elicitation with a noteworthy increase in xanthone production. In the present study, CHIT was administered to H. perforatum root cultures using three different elicitation protocols, and the increase in xanthone production was evaluated. The best results (550 % xanthone increase) were obtained by subjecting the roots to a single elicitation with 200 mg l(-1) CHIT and maintaining the elicitor in the culture medium for 7 days. To discriminate the effect of CHIT from that of the solvent, control experiments were performed by administering AcOH alone at the same concentration used for CHIT solubilization. Unexpectedly, AcOH caused an increase in xanthone production comparable to that observed in response to CHIT. Feeding experiments with (13)C-labeled AcOH demonstrated that this compound was not incorporated into the xanthone skeleton. Other short-chain monocarboxylic acids (i.e., propionic and butyric acid) have little or no effect on the production of xanthones. These results indicate that AcOH acts as a specific signal molecule, able to greatly enhance xanthone biosynthesis in H. perforatum root cultures.


Subject(s)
Acetic Acid/metabolism , Chitosan/administration & dosage , Hypericum/drug effects , Plant Roots/drug effects , Xanthones/metabolism , Acetic Acid/pharmacology , Carboxylic Acids/pharmacology , Hypericum/metabolism , Plant Roots/metabolism , Signal Transduction
18.
J Agric Food Chem ; 63(37): 8339-47, 2015 Sep 23.
Article in English | MEDLINE | ID: mdl-26345382

ABSTRACT

Apple scab, caused by the fungus Venturia inaequalis, is the most serious disease of the apple worldwide. Two cultivars (Malus domestica), having different degrees of resistance against fungi attacks, were analyzed by (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy. Aqueous and organic extracts of both apple flesh and skin were studied, and over 30 metabolites, classified as organic acids, amino acids, carbohydrates, phenolic compounds, lipids, sterols, and other metabolites, were quantified by means of one-dimensional (1D) and two-dimensional (2D) NMR experiments. The metabolic profiles of the two apple cultivars were compared, and the differences were correlated with the different degrees of resistance to apple scab by means of univariate analysis. Levels of metabolites with known antifungal activity were observed not only to be higher in the Almagold cultivar but also to show different correlation patterns in comparison to Golden Delicious, implying a difference in the metabolic network involved in their biosynthesis.


Subject(s)
Ascomycota , Disease Resistance , Fruit/metabolism , Magnetic Resonance Spectroscopy/methods , Malus/microbiology , Plant Diseases/microbiology , Carbohydrates/analysis , Fruit/chemistry , Fruit/microbiology , Lipids/analysis , Malus/metabolism , Metabolome , Phenols/analysis , Species Specificity
19.
Nat Prod Res ; 28(14): 1075-81, 2014.
Article in English | MEDLINE | ID: mdl-24730668

ABSTRACT

High-resolution proton NMR spectroscopy was performed on three Italian hazelnut cultivars, Tonda di Giffoni, Mortarella and Tonda Gentile Romana, and it allowed to define their metabolic profile. The hazelnuts were grown in the same pedoclimatic conditions in the Monti Cimini (Latium) area. The samples were obtained by using a modified Bligh-Dyer extraction protocol which did not give rise to artefacts arising from the demolition of macromolecular structures such as proteins and polysaccharides. Metabolites belonging to different chemical classes (amino acids, organic acids, carbohydrates, lipids and miscellaneous compounds) were identified and quantified. The three cultivars were discriminated by means of univariate (ANOVA) and multivariate (PCA) statistical analysis.


Subject(s)
Corylus/chemistry , Nuts/chemistry , Corylus/genetics , Italy , Metabolome , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Odorants , Volatile Organic Compounds
20.
Anal Bioanal Chem ; 397(6): 2477-90, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20464379

ABSTRACT

A sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of 13 steroidal anti-inflammatory drugs in bovine milk is presented. Due to their weakly acid nature, analytes were separated by ion suppression reversed phase chromatography and detected in positive-ion mode by a high flow electrospray source. Dexamethasone-d4 was used as internal standard. The sample preparation was simple and reliable; it included acidic deproteinization of milk followed by sample enrichment and clean-up, utilizing a C18 solid phase extraction cartridge. Recoveries exceeded 70% with an intra-day precision not larger than 12%. The efficiency of the sample clean-up and internal standardization rendered negligible the matrix effect, estimated by comparing standard and matrix-matched calibration curves. A small-scale reconnaissance was carried out on several raw and whole fresh milk samples. A large number of analyzed samples showed a chromatographic peak, in the retention time window of cortisol, at levels included between its decision limit (CCalpha) and detection capability (CCbeta). As a result of a heat-induced transformation, an isomeric product of triamcinolone was observed during the extract evaporation. Since this rearrangement might occur during the milk pasteurization process, LC-MS/MS and (1)H-NMR investigations were performed out to conclusively differentiate the two isomers. One- and two-dimensional proton NMR spectra were able to identify the transformation product as 9a-fluoro-11b,16a-trihydroxy-17b-hydroxymethyl-D-homoandrosta-1,4-diene-3,17a-dione.


Subject(s)
Glucocorticoids/analysis , Milk/chemistry , Tandem Mass Spectrometry/methods , Animals , Anti-Inflammatory Agents/analysis , Chromatography, Liquid/methods , Chromatography, Reverse-Phase , Spectrometry, Mass, Electrospray Ionization
SELECTION OF CITATIONS
SEARCH DETAIL
...