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This study was designed to establish the most effective solvent/technique for extracting antioxidant phytoconstituents from leaves and flower buds of Inula viscosa (L.) Aiton (Asteraceae) grown wild in Morocco. Maceration and hot extraction with methanol or water and Soxhlet ethanol extraction were utilized. The antioxidant potential was evaluated in vitro by DPPH, reducing power, and ferrous ions chelating activity assays. I. viscosa leaf and flower bud extracts displayed the strongest effect in the DPPH test, being the Soxhlet ethanol the most active ones (IC50 = 54.24 ± 0.21 μg/mL and 39.77 ± 0.23 μg/mL); thus, they were selected for further investigations. The antimicrobial efficacy of the Soxhlet ethanol extracts against ATCC and food isolates strains was assayed; the leaf extract showed the best activity, and Candida albicans was the most sensitive strain (MIC = 125 µg/mL). The extracts resulted non-toxic against Artemia salina. Among the phenolics characterised by HPLC-PDA-ESI-MS, hispidulin hexoside, patuletin and spinacetin were identified for the first time. [ABSTRACT FROM AUTHOR]

A new analytical approach to differentiate coffee botanical species and geographic origin is here reported. The method is based on the determination of the carbon isotope ratio (δ13C) of caffeine in green and in the corresponding roasted coffee, evaluated with a comprehensive approach using as second parameter the value of δ13C of the whole volatile fraction of the roasted coffee samples. The study initially evaluates the roasting effect on caffeine by using gas chromatography hyphenated to the carbon isotope ratio mass spectrometry (GC-C-IRMS). The results are then evaluated based on a novel comprehensive isotopic data evaluation (CIDE) model demonstrating that regardless the roasting effect and the different geographic origin, the coffee samples analyzed can be discriminated based on their botanical origin and in particular arabicas and robustas. [ABSTRACT FROM AUTHOR]

Retama sphaerocarpa occurs in the Mediterranean area of North-east Africa and in the Iberian Peninsula, and grows on a variety of soil types and climatic conditions. Used in Algerian folk medicine, it is a valuable species for revegetation and soil restoration. The aim of this study is to evaluate flavonoid composition and antioxidant and antiglycation properties of methanolic and aqueous extracts from R. sphaerocarpa fruits. HPLC-PDA/ESI-MS was used to identify/quantify flavonoid content. Antioxidant activity was evaluated by Folin-Ciocalteu, ORAC, FRAP, TEAC, and DPPH assays, and antiglycation capability by glucose/fructose-BSA assay. Results showed that fruits contain isoflavones (daidzein and genistein derivatives) and flavonols (apigenin, isorhamnetin, kaempferol and quercetin derivatives), and extracts (especially the methanolic one, richer in flavonoids) possess good in vitro antioxidant and antiglycation properties. These findings evidence that R. sphaerocarpa fruits are a source of valuable phytochemicals, with potential applications in the field of phytopharmaceuticals and in food industry. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

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]

A new method for the analysis of oxygen heterocyclic compounds in bergamot, mandarin and sweet organge oils by capillary electrochromatography (CEC) is reported. The fused silica capillaries employed were slurry-packed in house with 3 μm ODS1 stationary phase. The repeatability of the technique has been investigated with two neutral standard mixtures. Conditions for the analysis have been optimised by varying several parameters such as applied voltage, temperature, composition of the buffer and percentage of organic solvent. The best separations were obtained using the buffer acetonitrile/TRIS 10 mM at pH 7.8 in the ratio 80∶20. The results were compared with those obtained by high performance liquid chromatography (HPLC) in terms of time of analysis, resolution and efficiency. A study on the behaviour of oxygen heterocyclic compounds analysed with a “non-aqueous” mobile phase has also been carried out. [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]