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Abstract: The triacylglycerol (TAG) profiles present in real world lipidic samples are usually quite complex and, as such, monodimensional high-performance liquid chromatographic (HPLC) techniques are inadequate when challenged with such matrices. In this respect, the complementary use of silver-ion (Ag) and non-aqueous (NA) reversed-phase (RP) HPLC can be exploited if thorough TAG separations are required. The present investigation reports the employment of a newly developed comprehensive LC (LC×LC) system, based on the different separation mechanisms of the aforementioned techniques, and applied to a rice oil sample. The approach was successful in the separation of a high number of solutes, otherwise unachievable through monodimensional LC. Furthermore, the use of atmospheric pressure chemical ionization mass spectrometry (APCI-MS), as detection system, provided a third analytical dimension boosting the identification power of the comprehensive chromatographic method. [Copyright &y& Elsevier]

The lemon essential oil volatile fraction is considered one of the most complex amongst all citrus oils being traditionally determined by monodimensional GC. This conventional method, although providing important qualitative[sol ]quantitative information, lacks the necessary resolving power for the separation of several critical compounds. In the past, this has been often accomplished through the employment of conventional multidimensional chromatographic methods, which can only achieve the characterization of single parts of a sample and whose analysis times are generally high. Comprehensive bidimensional gas chromatography (GC × GC) is gaining an excellent reputation for the separation of complex samples. This powerful analytical technique is characterized by both an enhanced resolving power and a great potential for the classification of unknowns through chromatographic retention patterns. In this research, these features are exploited in the analysis of a lemon essential oil. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The oxygen heterocyclic compounds (coumarins, psoralens, and polymethoxylated flavones (PMFs)) present in citrus essential oils (lemon, mandarin, sweet orange, bitter orange, bergamot, grapefruit, and lime) were analysed by an HPLC-MS system equipped with an APcI source. The mass spectra obtained at different voltages of the “sample cone” have been used to build a library. Citrus essential oils have been analysed with this system, using an optimised normal phase HPLC method, and the mass spectra were compared with those of the home made library. This method allowed the rapid identification and the characterisation of the oxygen heterocyclic compounds of citrus oils, the detection of some minor components for the first time in some oils, and the detection of authenticity and possible adulteration of the oils. [ABSTRACT FROM AUTHOR]

Abstract: In such a complicated field as proteomic analysis, scientists are more and more challenged in implementing separation systems capable to provide enhanced separation power, as well as sensitivity of detection for adequate identification and, to a lesser extent, quantification of the separated compounds. To address such issues, several combinations of different separation modes have been investigated in comprehensive liquid chromatographic platforms, in which the entire sample eluted from the first dimension is subjected to a secondary chromatographic separation. The different applications exploited for comprehensive LC analysis of intact or digested proteins are the focus of this review, in which advantages and disadvantages of the different columns combinations, interfaces, and operating modes are pointed out. The combination with mass spectrometry as part of the total system is stressed, and illustrated in more detail. Theoretical concerns and practical requirements will be briefly discussed, as well. [Copyright &y& Elsevier]

Focuses on a study that investigated the variation in tocopherol in Italian virgin olive oils. Materials and methods; Results and discussion.

This study was designed to define and compare the antioxidant and cytotoxic properties of polar extracts obtained from basal leaves (It-BL), cauline leaves (It-CL) and flowers (It-F) of Isatis tinctoria L. growing wild around Acireale (Sicily, Italy). The phenolic profile was characterized by HPLC-PDA-ESI-MS analysis and the correlation between phenolic content and the observed biological effects was established. Further, LC/MS analysis showed that the extracts contain glucosinolates at very low concentrations. The antioxidant activity of the extracts was tested in vitro; It-F was the most effective in the DPPH test (IC50 = 0.437 ± 0.003 mg/mL), whilst It-CL showed the best reducing power (1.546 ± 0.006 ASE/mL) and ferrous ions chelating activity (IC50 = 0.564 ± 0.011 mg/mL). The extracts exhibited anti-proliferative effects against three different human thyroid carcinoma cell lines, and It-BL displayed the strongest activity; particularly, it markedly inhibited the growth of CAL-62 cells, causing nearly 85% reduction of viability at the highest tested dose. No cytotoxicity against Artemia salina was observed. The results of our investigations indicate that the polar extracts obtained from I. tinctoria are a potential source of antioxidant and anticancer compounds, which could be suitable for nutraceutical and therapeutic applications. [ABSTRACT FROM AUTHOR]

The present paper provides an overview of the application of ionic liquid (IL) columns for GC analysis of fatty acid methyl esters (FAMEs). Although their separation can be carried out utilizing GC columns containing polar stationary phases, some ILs have been employed as stationary phases, either commercial or laboratory made, in GC analysis. Monodimensional and bidimensional GC methods have been optimized in order to achieve the best separation especially considering the geometric and positional isomers of unsaturated fatty acids. Several methods for the analysis of trans-fatty acids have also been reported. The use of GC–GC, using either the same IL columns or different columns in the first and second dimensions, allowed the separation of a large number of FAMEs. The application of the IL columns for GC analysis of FAMEs in different types of real samples is described, e.g., oil of different nature (fish, flaxseed, and olive), margarine and butter, biodiesel, milk, bacteria etc. [ABSTRACT FROM AUTHOR]

White truffle ( Tuber magnatum Pico ) is one of the most valuable delicacies of the Italian and French cuisine. Previous works on truffle aroma report sulfur compounds and short-chain aldehydes as typical constituents which abundance is influenced by storage conditions. In this study, the head space of truffle aroma has been evaluated by two different (innovative) approaches: HS-SPME extraction and comprehensive two-dimensional gas chromatography (GCxGC), exploiting a dual-stage loop-type modulator within a GC system with simultaneous FID and MS double detection, analysis and Gas sensors array system analysis. Gas chromatographic peak identification was carried out by means of dedicated laboratory-made GC–MS libraries and comparison of Retention Indices with those retrieved from literature, while peak quantification by means of a specifically designed software for comprehensive GC. The truffle samples were stored at +8 °C for four days in three different ways: wrapped in blotting paper or covered by rice or under vacuum. Eighty compounds were identified with high confidence (>90% of mass spectra similarity). PCA of compounds relative percentages showed differences among the fresh product and truffles stored in rice and under vacuum; on the contrary no significant volatiles composition modification was observed for truffles stored in paper. [ABSTRACT FROM AUTHOR]

Abstract: The characteristic aromatic composition of white truffles (Tuber magnatum Pico) determines its culinary and commercial value. However modifications of truffle organoleptic proprieties occur during preservation. A study of headspace of white truffles by using Electronic nose (E-nose), gas chromatography–mass spectrometry (GC–MS) and sensory analyses was performed. Truffles were stored at different conditions for 7days: +4 and +8°C wrapped in blotting paper or covered by rice or none of the above. Headspace E-nose measurements and sensory analyses were performed each day. Statistical multivariate analysis of the data showed the capability of E-nose to predict sensorial analysis scores and to monitor aroma profile changes during storage. Truffle’s volatile molecules were also extracted by headspace solid phase microextraction technique and separated and identified by GC–MS. Partial Components Analysis of data was performed. E-nose and GC–MS results were in agreement and showed that truffle storage in paper at +8°C seemed to be the best storage condition. [Copyright &y& Elsevier]

Abstract: The research of new tyrosinase inhibitors is currently important for the development of skin whitening agents; particularly, birch leaves extracts are included in many skin cosmetic products. In this study, the potential ability of Betula pendula leaves ethanolic extract (BE) was evaluated on mushroom tyrosinase activity. Results showed that BE was capable to inhibit dose-dependently l-DOPA oxidation catalyzed by tyrosinase. The inhibition kinetics, analyzed by Lineweaver–Burk plots, showed a noncompetitive inhibition of BE towards the enzyme, using l-DOPA as substrate. The inhibitory mechanism of BE as studied by spectrophotometric analysis, demonstrated its ability to chelate copper ion in the active site of tyrosinase. In addition, BE exhibited Fe2+-chelating ability (IC50 =614.12±2.14μg/mL), reducing power and radical-scavenging properties (IC50 =137.22±1.98μg/mL). These results suggest the usefulness of birch leaves extracts in cosmetic and pharmaceutical industries for their skin-whitening and antioxidant effects. Determination of the polyphenolic compounds in BE extracts was afterward achieved by means of high-performance liquid chromatography (HPLC) with photodiode array (PDA) and mass spectrometry (MS) detection. A total of 25 compounds were positively identified, through the complementary analytical information, and are reported in such a matrix for the first time. Knowledge on the qualitative composition and contents of these natural sources in fact represents mandatory information, for rational consumption and correlation of the beneficial effects to the specific amounts. [Copyright &y& Elsevier]

Numerous samples of Italian cold-pressed bergamot oils, representative of the industrial production of the last three seasons (2008/09, 2009/10 and 2010/11), as well as several samples of bergapten-free, concentrated and recovered oils, have been extensively investigated in the present study. The samples were analyzed to determine the composition of the volatile fraction, the oxygen heterocyclic compounds, the enantiomeric distribution of twelve volatile components and the isotopic ratios of selected volatiles. Differences from previous studies emerged. The recent improvement in cultural practices is confirmed by the increase of linalool and linalyl acetate, indicative of better quality of the essential oils. The seasonal variation of the enantiomeric excess of α-terpineol, characteristic of cold-pressed bergamot oils, is confirmed. Some oxygen heterocyclic compounds are here quantitatively determined for the first time. The presence of herniarin is confirmed in genuine samples through high-pressure liquid-chromatography--mass spectrometry-ion trap--time of flight (HPLC-MS-IT-TOF). The isotopic ratios herein reported, tbr all the samples analyzed, represent a useful tool for the evaluation of genuineness of cold-pressed and processed bergamot oils. [ABSTRACT FROM AUTHOR]

Abstract: The present study was designed to define the phenolic profile and the biological potential of berries methanol extract of Juniperus drupacea Labill. from Turkey. The total phenolic content (Folin–Ciocalteau assay) was 48.06±0.99mgGAE/g extract. The HPLC-DAD-ESI-MS analysis allowed the determination of the complete phenolic profile of J. drupacea berries. Phenolic acids represented more than 60% of the total phenolics, and tyrosol was the major one (1324±0.64μg/g extract); within the flavonoids amentoflavone was detected as the main constituent (927±0.35μg/g extract). The extract exhibited good antioxidant properties, as determined by different in vitro models: DPPH test (IC50 0.38±0.02mg/mL), reducing power (12.63±0.14ASE/mL), Fe2+ chelating ability (IC50 2.26±0.06mg/mL), and TBA test (IC50 2.47±1.13μg/mL). Cytotoxicity against Artemia salina was highlighted (LC50 489.47±27.8μg/mL), and a significant decrease (p ⩽0.05; p ⩽0.01) in HepG2 cells viability was observed at the higher concentrations (5–10μg/mL). The extract displayed good antibacterial activity towards Gram-positive bacteria and in particular Staphylococcus aureus was the most susceptible strain (MIC 78.12μg/mL). [Copyright &y& Elsevier]

Essential oils from the aerial parts of Sicilian Teucrium flavum L., isolated by using microwave-assisted hydrodistillation (MHD), were analyzed for the first time at various seasonal stages (vegetative and budding stage) by means of GC/MS and GC-FID; the flowers and fruits were also subjected to examination. More than 80 compounds were identified as oil components. The leaf, flower and fruit oils were characterized by a predominance of sesquiterpenes, such as β-caryophyllene (3-5 g/100 g), germacrene D (4-14 g/100 g), b-bisabolene (32-49 g/100 g); the total amount of sesquiterpene hydrocarbons contained in each oil was 56-70 g/100 g, the oxygenated derivatives were in the range of 9-20 g/100 g. The monoterpene hydrocarbons in all samples (leaves, flowers, fruits) were contained in very low amounts, from 0.2 to 1.6 g/100 g, and were the least representative fraction of the oils. Oxygenated aliphatic compounds, especially esters, were also detected. The results can be useful to support, by means of a safe reliable sample preparation (MHD) and analytical (GC) technique, the research on medicinal plants belonging to Mediterranean flora. [ABSTRACT FROM AUTHOR]

Extracts of Melaleuca cajuputi were obtained by supercritical (carbon dioxide) extraction and solvent (hexane) extraction methods. This work is aimed at adapting the green technology of using supercritical CO2 (SC-CO2) as solvent in a batch process to extract Melaleuca cajuputi leaves. The plant leaves were collected from Trengganu, Malaysia. Cajuputi extract analyses were performed by GC and GC/MS. The maximum yields obtained were 4.2% and 6.0%, respectively, by supercritical fluid (SFE) and solvent extraction (SE). Several compounds were identified and significant qualitative and quantitative differences were observed under different conditions. The major components of Cajuputi oil consisted of sesquiterpenes (δ-elemene, β-elemene, β-caryophyllene, α-humulene, 9-epi-β-caryophyllene), their oxygenated derivatives (viridiflorol, platyphyllol, β-eudesmol, bulnesol, (Z,Z)-farnesol and (E,E)-farnesal) and polyphenolic ketones (isoeugenitine and three unknown compounds). [ABSTRACT FROM AUTHOR]

Nowadays, multidimensional techniques occupy an expanding niche in separation science, being strong evidence that one-dimensional systems are by themselves inadequate, especially when challenged with highly complex samples. No exceptions are foodstuffs: analytical multidimensional methods not only allow the qualitative and quantitative determination of the main compounds, but can also be selective and sensitive enough to permit the determination of minor components. The present review gives an overview of the application of three main types of multidimensional separations, off-line, on-line/heart-cutting, and comprehensive liquid chromatography, for the analysis of food and beverages. The principles, advantages, and disadvantages of each approach are briefly described. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, a novel strategy including the use of two different comprehensive HPLC methods has been employed to study the whole carotenoid composition of mandarin essential oil. Thus, two different fully orthogonal two-dimensional HPLC methods have been used. A silica microbore column was coupled to a C18 monolithic column to study the mandarin saponified extract, while the coupling of a cyano microbore column to a C18 monolithic column was employed to study the intact mandarin essential oil sample in order to characterize the native carotenoid esters composition. Detection was performed by connecting a photodiode array detection (DAD) system in parallel with a MS detection system operated with an atmospheric pressure chemical ionization (APCI) interface. Thus, the carotenoid identification was carried out by combining the information provided by the DAD and MS systems and the peaks relative position in the two-dimensional chromatograms. [Copyright &y& Elsevier]

Abstract: Lemon liquor, commonly known as “Limoncello”, obtained from maceration of lemon peels in ethanol, water and sugar, has become a product in great demand in the international market. Scientific literature reports just a few studies on Limoncello, however, in consideration of the data available, it can be assumed that in many cases the need of industry for standard products leads to the addition of essential oils and/or related to the alcoholic syrup. Aim of this study was therefore to investigate the volatile and non volatile fraction of lemon liquors of different commercial brands, using solid phase microextraction, gas chromatography-quadrupole mass spectrometry, chiral-gas chromatography and reversed phase HPLC. [Copyright &y& Elsevier]

Abstract: Various combinations of PEG–silica, phenyl–silica and C18 columns in a single-column or serial (tandem) arrangement in the first dimension and a monolithic Chromolith column in the second dimension were tested for comprehensive two-dimensional (2D) LC×LC separation of phenolic and flavone natural antioxidants. The combinations of different stationary phase chemistries provided low selectivity correlations between the first-dimension and the second-dimension separation systems. Improvement in system orthogonality, bandwidths suppression, more regular band distribution over the whole 2D retention plane and increased peak capacity in different 2D setups was achieved by using gradients with matching profiles running in parallel in the two dimensions over the whole 2D separation time range. Instead of two sampling loops, two alternating trapping XTerra columns were used for sample fraction transfer from the first-dimension column to the second dimension. Stronger retention on the XTerra columns in comparison to PEG–silica or phenyl–silica columns in the first dimension allowed using focusing of sample fractions in narrow zones on the top of a trapping column and back-flushing into the second dimension in a very low volume of the mobile phase. This fraction transfer modulation provided significant bandwidth suppression in the second dimension. 2D systems with optimized stationary phase selectivity, parallel gradients and fraction transfer modulation using two trapping columns were applied for the analysis of natural antioxidants in beer and wine samples. [Copyright &y& Elsevier]

Leaf-derived essential oils isolated from Artemisia arborescens L. (Asteraceae) were analyzed by using GC/MS and GC-FID (for compound quantification); a total of 82 components were determined. The oils were derived from plants collected at the vegetative stage and originating from three locations in southern parts of Italy: Calabria, Sicily and the island of Lipari (Eolian Islands). In general, the chemical compositions were rather similar with some major differences regarding, in particular, the amounts of oxygenated compounds, such as camphor, chamazulene and α- and β-thujones. The research work was extended to the determination of a series of chiral compounds, as also the olfactive analysis of the aroma-active compounds, with the aim of acquiring an enlargened view on this specific sample-type. [ABSTRACT FROM AUTHOR]

Thirty-one red wines of "Protected Geographical Indication", including most of the wine cultivars grown in Sicily, were assayed for their phenolic content. Individual phenolic compounds were identified and quantified by HPLC with a photo-diode array (PDA) coupled on-line with a MS system. The total phenolic content was evaluated by the Folin-Ciocalteau method and the antioxidant capacity was measured by the DMPD (N,N-dimethyl-p-phenylendiamine) method. The results provide new insight into the polyphenolic composition of commercial Sicilian wines, and highlight some interesting points about the different wine typologies. In particular, the Merlot wines produced in Sicily, similar to those produced by other allochthonous grapes, generally have a higher polyphenolic content. Based on the data given, Merlot wines appear to be an important source of dietary polyphenolic antioxidants. It may be supposed that wines produced from this grape typology in Sicily are endowed with properties that have potential health benefits. [ABSTRACT FROM AUTHOR]

Abstract: Triacylglycerols (TAGs), the major components in fats and oils, are a good example of natural complex mixtures. The best technique for the separation of such samples is certainly high performance liquid chromatography (HPLC). Monodimensional HPLC separations are often not sufficient to resolve all the components of interest. The present investigation reports the employment of a comprehensive LC system, based on the different separation mechanisms of silver ion (Ag) and non-aqueous reversed phase (RP) HPLC, used respectively in the first and second dimension, and applied to the analysis of plant-derived natural lipidic matrixes. The results obtained show that the approach enables both the separation of a high number of components and the attainment of structural information due to the formation of group-type patterns on the bidimensional (2D) plane. The employment of atmospheric pressure chemical ionisation (APCI) mass spectrometry as detection system was of substantial support for reliable TAG assignment, thus increasing the identification power of this comprehensive chromatographic approach. [Copyright &y& Elsevier]

The effect of lactation on the flavour of cheese made with raw milk of Maltese goats bred in Sicily (Italy) was studied. The goat cheese flavour was analyzed for the first time by Solid Phase Microextraction (SPME) coupled with Gas chromatography/Mass Spectrometry (GC/MS). The suitability of the analytical method was determined by calculating the coefficients of variation (CV%). Data were processed using ANOVA in relation to the stage of lactation. Forty four components (methyl ketones, free fatty acids, aldehydes, alcohols, esters, terpenes and lactones) were identified and quantified. The most representative fatty acids were butyric, baproic, baprylic and bapric (from 30 to 75% of the total identified fraction). Many other important cheese odorants were determined giving a substantial contribution to the aroma profile. The highest percentages were, for alcohols: isoamyl and phenethyl alcohols at the 2nd month of lactation (6.82% and 2.81%, respectively); as regards ketones, at the 5th and 6th months of lactation: 2-heptanone (7.88% and 10.10%, respectively) and 2-nonanone (18.52% and 14.81%, respectively). The highest percentage of esters (2.5%) was found in the 7th month of lactation. The lactation significantly influenced the flavour components. Good CV percentages were obtained (less than 5.0). This easy and fast method permits a quali-quantitative description of the goat's cheese flavour in relation to the lactation. The results testify the difficulty in attributing the variations to a single effect so as to standardize this product, even if this analytical method could help to give some indications, before marketing, regarding the consumer's perception and acceptance. [ABSTRACT FROM AUTHOR]

The effect of lactation on the flavour of cheese made with raw milk of Maltese goats bred in Sicily (Italy) was studied. The goat cheese flavour was analyzed for the first time by Solid Phase Microextraction (SPME) coupled with Gas chromatography/Mass Spectrometry (GC/MS). The suitability of the analytical method was determined by calculating the coefficients of variation (CV%). Data were processed using ANOVA in relation to the stage of lactation. Forty four components (methyl ketones, free fatty acids, aldehydes, alcohols, esters, terpenes and lactones) were identified and quantified. The most representative fatty acids were butyric, baproic, baprylic and bapric (from 30 to 75% of the total identified fraction). Many other important cheese odorants were determined giving a substantial contribution to the aroma profile. The highest percentages were, for alcohols: isoamyl and phenethyl alcohols at the 2nd month of lactation (6.82% and 2.81%, respectively); as regards ketones, at the 5th and 6th months of lactation: 2-heptanone (7.88% and 10.10%, respectively) and 2-nonanone (18.52% and 14.81%, respectively). The highest percentage of esters (2.5%) was found in the 7th month of lactation. The lactation significantly influenced the flavour components. Good CV percentages were obtained (less than 5.0). This easy and fast method permits a quali-quantitative description of the goat's cheese flavour in relation to the lactation. The results testify the difficulty in attributing the variations to a single effect so as to standardize this product, even if this analytical method could help to give some indications, before marketing, regarding the consumer's perception and acceptance. [ABSTRACT FROM AUTHOR]

This study was carried out to deter mine the carotenoid composition of blond and pigmented sweet orange and mandarin essential oils. The oils were analysed after alkaline hydrolysis by RP-HPLC/PDA. Fourteen compounds, carotenes and xanthophylls, were identified. Sweet orange and mandarin oils have characteristic carotenoid profiles that could be used to detect the addition of sweet orange to mandarin essential oil. [ABSTRACT FROM AUTHOR]