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Eryngium dilatatum Lam. is a thorny Iberian Peninsula endemic species belonging to the Apiaceae family that has not been previously analysed from a chemical point of view. Following our studies on this genus, we characterized the chemical composition of the essential oils from the different parts (inflorescences, stems + leaves, and roots) of this species; these parts were gathered in Cádiz (Spain). The specimens were collected in July during the flowering period and air-dried before the oil extraction by hydro-distillation. The essential oils were analysed by gas chromatography and gas chromatography coupled with mass spectrometry. The different parts of the plant yielded low amounts of pale yellow oil, with the roots being the fraction that provided the lowest amount of oil. The chemical characterization of the essential oils showed qualitative and quantitative differences between the fractions examined, but all of them showed the same principal compound, germacrene D (9.1–46.5%). Similarly, all the fractions shared most of their representative constituents, with their percentage compositions being different from one sample to the other: α-cadinol (3.8%), bicyclogermacrene (3.5%), octanal (3.1%), and spathulenol (2.5%) were found in the inflorescences; octanal (8.1%), α-cadinol (3.7%), δ-cadinene (3.6%), (E)-caryophyllene (2.6%), bicyclogermacrene (2.5%), and spathulenol (2.4%) were found in the stems and leaves; and spathulenol (4.6%), α-cadinol (4.4%), khusinol (3.2%), α-muurolol (3.1%), and δ-cadinene (2.6%) were found in the roots. As far as we know, this is the first report about the chemical composition of this endemic species of the Iberian Peninsula. It contributes to the knowledge of this species and to the genus to which it belongs. This species could be considered as a natural source of germacrene D, which is a sesquiterpene hydrocarbon with active properties.

The Eryngium L. genus belongs to the Apiaceae family and, with about 250 species, has a cosmopolitan distribution. Only fourteen of the twenty-six species described in Flora Europaea grow in the Iberian Peninsula. One of these is Eryngium galioides Lam., a small annual plant (2–30 cm) that grows in open dry places in the mid-west of the Iberian Peninsula. For this study, the whole plant (aerial parts and roots) of this species was gathered in Guadalajara (Spain). The essential oil of this population was extracted by hydro-distillation and analyzed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC-MS). It is worth noting that this species gave rise to a relatively high essential oil yield (0.48%) in comparison with other species of this genus. E. galioides oil consisted of a complex mixture of more than 70 compounds. The main constituents of this oil were identified as valencene (49.7%) and a phyllocladene isomer (23.7%), both representing more than the 70% of the total oil. Other representative compounds of this oil were found to be β-chamigrene (6.0%), γ-muurolene (3.4%), (E)-caryophyllene (3.0%) and β-elemene (1.6%). As far as we know, this is the first report about the chemical composition of E. galioides essential oils. With this work, we contribute to the knowledge of this genus and provide a chemical and botanical basis to promote the in vitro cultivation of E. galioides as a source of essential oils rich in bio-actives for application in different fields.

In this work, the simultaneous extraction of bioactives (organosulfur compounds, such as S-allyl-L-cysteine (SAC), carbohydrates, such as neokestose and neonystose, and total phenolic compounds) from aged garlic has been optimized for the first time to obtain multifunctional extracts for further application as food ingredients. Analytical methods using liquid chromatography coupled to mass spectrometry (HPLC-MS) and by hydrophilic interaction liquid chromatography with evaporative light scattering detection (HILIC-ELSD) were also previously optimized. High sensitivity (limits of detection between 0.013 and 0.77 µg mL) and appropriate repeatability (< 12%) and accuracy (> 92%) for the analysis of bioactives were achieved. After selecting water as the extraction solvent and microwave-assisted extraction (MAE) as the most efficient technique, operation conditions were optimized using a Box-Behnken experimental design (60 min; 120 °C; 0.05 g mL; 1 cycle) to maximize the content of bioactives from different aged garlic samples. Regarding organosulfur compounds, only SAC (traces-2.32 mg g dry sample) and cycloalliin (1.23–3.01 mg g dry sample) were detected in all samples, while amino acids such as arginine (0.24–3.45 mg g dry sample) and proline (0.43–3.91 mg g dry sample) were, in general, the most abundant. Bioactive carbohydrates (from trisaccharides to nonasaccharides) were only detected in fresh garlic and aged garlic processed under mild conditions, whereas all garlic extracts showed antioxidant activity. The developed MAE methodology is shown as a successful alternative to other procedures for the simultaneous extraction of aged garlic bioactives intended by the food and nutraceutical industries, among others.

A microwave-assisted extraction (MAE) procedure has been optimized to simultaneously provide multifunctional extracts of Mentha sp. leaves with improved antioxidant properties and, for the first time, with optimal antimicrobial activity. Among the solvents evaluated, water was selected as the extractant in order to develop a green procedure and also for its improved bioactive properties (higher TPC and Staphylococcus aureus inhibition halo). MAE operating conditions were optimized by means of a 3-level factorial experimental design (100 °C, 14.7 min, 1 g of dry leaves/12 mL of water and 1 extraction cycle), and further applied to the extraction of bioactives from 6 different Mentha species. A comparative LC-Q MS and LC-QToF MS analysis of these MAE extracts was carried out for the first time in a single study, allowing the characterization of up to 40 phenolics and the quantitation of the most abundant. Antioxidant, antimicrobial (Staphylococcus aureus, Escherichia coli and Salmonella typhimurium) and antifungal (Candida albicans) activities of MAE extracts depended on the Mentha species considered. In conclusion, the new MAE method developed here is shown as a green and efficient approach to provide multifunctional Mentha sp. extracts with an added value as natural food preservatives.

im: In this work, the development for the first time of a green and efficient method to obtain bioactive extracts from Mentha x rotundifolia leaves has been investigated. Methods: The efficiency of three techniques [microwave-assisted extraction (MAE), subcritical water extraction (SWE), and ultrasound-assisted extraction (UAE)] was compared in terms of total phenolic content (TPC) and antioxidant activity [1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis (3-ethylbenzthioazoline-6-sulfonic acid) (ABTS) assays]. Results: Under similar operating conditions, SWE outperformed MAE and UAE for providing M. rotundifolia extracts with improved antioxidant activity. Further in-depth optimization of the SWE method by means of a Box-Behnken experimental design showed 120°C, 5 min, 0.08 g dry sample: 1 mL water and 2 extraction cycles as optimal experimental parameters to provide the maximum yield of phenolics and the highest bioactivity. The application of the developed SWE method to M. rotundifolia leaves collected in different annuities (2014–2017) showed, in general, no significant differences regarding both composition and antioxidant capacity, as expected from plant samples grown in field under drip irrigation conditions. Conclusions: The SWE method here optimized is shown as a sustainable and efficient alternative for providing bioactive M. rotundifolia extracts with application as functional ingredients, natural preservatives, etc. in the food industry, among

Deep eutectic solvents (DES), and especially natural deep eutectic solvents (NADES), are advantageous alternatives over non-environmentally friendly organic solvents traditionally employed for sample preparation in analytical chemistry. Moreover, the use of DES has recently experienced remarkable growth to fulfill the green analytical chemistry principles. One of their most influential characteristics, which should be determined for each new DES, is viscosity. Manual or automatic viscometers are usually employed to this aim, but their use is sometimes hampered by characteristics of DES such as their variable water content or their wide viscosity range. In this study a proof-of-concept of the feasibility of employing a capillary electrophoresis (CE) instrument to determine this physicochemical property is shown. No change in the commercial instrument is required, and advantages such as applying controlled pressure and temperature, online UV detection at several wavelengths, use of extremely low volumes of solvents and viscosity markers, automation, etc., allow the easy and affordable adaptation of this method to different DES. As example of application, CE methods were used for viscosity measurement of ten different DES, including hydrophilic (based on either choline chloride or betaine) and hydrophobic ones (based on thymol), within two orders of magnitude (6 to 500 mPa⋅s). Agreement between the experimental results obtained with the CE instrument and data gathered by a commercial viscometer adequate for solvents without water or with published data (when available), is shown. Contribution of using DES to the green analytical chemistry principles is reinforced by the characterization for the first time of these solvents with the more sustainable and high applicability CE method here proposed.

Despite the widespread use of artichoke-based food supplements for obesity control (FSOC), studies on evaluation of the quality/authenticity of these commercial products are scarce. To that aim, a new multi- analytical strategy, based on the use of gas chromatography coupled to mass spectrometry (GC–MS) and high performance liquid chromatography coupled to ultraviolet and mass spectrometry detection (HPLC- UV-MS), in combination with chemometrics, has been developed. Twenty-one artichoke FSOC and dif- ferent bract and leaf extracts (used as reference samples) were analysed. Sugars, inositols, caffeoylquinic acids, dicaffeoylquinic acids, flavonoids and their glycosides were detected in reference samples and in most artichoke FSOC. Low concentrations of bioactives, and the presence of other compounds probably related to heat treatment during manufacturing (difructosyl anhydrides, 3-deoxyglucosone), or to the ad- dition of caloric additives (maltose, maltotriose) or non-declared plants (e.g. pinitol, disaccharides, silybin derivatives) were also detected in some FSOC by either GC–MS or HPLC-UV-MS. Application of Principal Component Analysis to the combined GC–MS + HPLC-UV data matrix, proved that this multi-analytical strategy provides advantages over single analytical techniques for the detection of the wide variety of fraudulent practices affecting authenticity of artichoke FSOC and for assessment of their quality.

Volatile fingerprinting by Headspace-Solid-Phase Microextraction followed by Direct Injection Mass Spectrometry (HS-SPME DIMS) has been assessed for the first time as an alternative approach to gas chromatographic methods (HS-SPME GC-MS) for the rapid classification of honey botanical origin. In order to fully evaluate the potential of SPME for honey authentication, samples from different botanical sources (eucalyptus, citrus, acacia, rosemary and honeydew) were analyzed by both approaches using either carboxen/polydimethylsiloxane (C/PDMS) or polyacrylate SPME fibers. These datasets were further subjected to different supervised and unsupervised chemometric techniques, including powerful machine learning methods such as FreeViz, not previously applied for this purpose. The best overall classification rate (99% success), outperforming that provided by GC-MS data (98.25% success), was obtained when partial least squares-linear discriminant analysis was applied to mass spectral fingerprints gathered by C/PDMS fiber. The HS-SPME DIMS approach here optimized is shown as an advantageous alternative in terms of analysis time over chromatographic methods (2 vs 50 min), as well as a reliable and cost-efficient approach for honey source authentication issues both in research and food industry fields.

Garcinia gummi-gutta based food supplements (GFS) are widely commercialized due to their antiobesity activity, which has been mainly attributed to their high content in (−)-hydroxycitric acid [(−)-HCA]. In order to overcome the limitations related to selectivity and sensitivity of the HPLC-UV methods usually employed for the analysis of this compound, a GC–MS method was fully developed for the first time and validated. Water with 0.1 % formic acid was used for the solubilization of (−)-HCA stabilized in the form of salt in GFS. After a drying step, different derivatization solvents were tested and only trifluoroacetic acid (TFA) allowed the complete dissolution of (−)-HCA. Regarding silylation, the best results were obtained by cold dropwise addition of hexamethyldisilazane and subsequent heating at 45 °C for 90 min. After optimizing the chromatographic conditions, the stability of derivatives for 1 month was also assessed. This new methodology was also applied to determine the (−)-HCA content of 12 commercial GFS. Experimental values ranged from 0.86 to 61%. Forty-two percent of the analyzed samples did not meet the (−)-HCA content declared on the label and 2 GFS showed HCA concentrations lower than 10% (0.86 and 6.0%), which puts into question their effectiveness in regulating obesity. One advantage of this new methodology is that it allows the qualitative and quantitative analysis of (−)-HCA in GFS without coelutions with other interfering compounds and it avoids the solubility problems presented by HCA salts. Moreover, the coupling of GC to MS provides more reliable identification of compounds present in GFS.

A new multianalytical methodology based on gas chromatography (GC) and liquid chromatography (LC) coupled to mass spectrometry (MS) has been proposed to evaluate frauds affecting the composition of Coleus forskohlii root supplements (FKS). After optimization and validation of chromatographic methods, 24 FKS were analyzed. Forskolin, their main bioactive component, was only found in 50% of the FKS evaluated (in the 0.032–17.1% range), with 27% of these supplements showing concentrations of this bioactive lower than those declared in their labels. Application of this methodology also proved to be successful for the detection of frauds regarding the replacement of C. forskohlii by other vegetable sources (green tea, soy leaves and a plant of the Berberidaceae family) in 17% of supplements analyzed. A study on stability of forskolin under accelerated conditions allowed to rule out its degradation as responsible for the lack of this bioactive or other natural constituents in 25% of FKS evaluated. It can be concluded that the multianalytical methodology here developed is an advantageous alternative to address the wide diversity of frauds affecting these supplements.

The establishment of the corresponding standards of quality to promote the commercialization of Rubus ulmifolius Schott (Rosaceae) blackberries from Calabria (Italy) has been aimed in this study. Data on the volatile composition gathered by Solid-Phase Microextraction (SPME) followed by GC–MS have been complemented with the study for the first time of physicochemical parameters and antioxidant capacity of wild and cultivated blackberries collected in seven different locations of Calabria. Wild fruits showed significantly higher dry matter content (16.34–22.14%) and pH (3.92–5.12) and lower total acidity (0.23–0.74 as % of citric acid) compared to the cultivated sample (dry matter: 15.31%; pH: 3.30 and total acidity: 1% citric acid), whereas colour and total soluble solids were similar. Antioxidant capacity (DPPH assay) of wild blackberries, correlated (r = 0.71) with results from ABTS assay, was significantly higher (SE = 1.6–3.4 mg DW), in agreement with its higher content of total anthocyanins and total phenolics. Ethanol (11.8–32.4%), trans-2-hexenal (2.7–21.3%), methylbutanal (5.7–17.4%), and ethyl acetate (4.6–11.9%) were the major compounds in both wild and cultivated blackberries. Although the presence or relative concentration of several volatiles (e.g. p-cymen-8-ol, decanal, 3-hydroxy esters, etc.) seemed to be characteristic of the harvest location/blackberry type, further research on a higher number of samples should be carried out to confirm these results. The comprehensive characterisation addressed for the first time in this paper is a valuable preliminary contribution to satisfy the demand by consumers and farmers of objective data to support the premium quality of Calabrian blackberries. Graphical abstract: [Figure not available: see fulltext.]

Se ha extraído mediante hidrodestilación el aceite esencial de diez especies usadas como pimienta: Piper borbonense, P. capense, P. retrofractum, P. nigrum, Zanthoxylum bungeanum y Z. armatum, Lindera neesiana, Ruta chalepensis, Schinus terebenthifolia, Pimenta dioica. Los análisis realizados mediante cromatografía de gases acoplada a espectrometría de masas encontraron que todas presentan ß-felandreno y derivados de cariofileno y felandreno, siendo estos compuestos de propiedades pungentes los característicos de la especia pimienta. El rendimiento de esencia varía desde 0,43% para R. chalepensis hasta 7,61% para P. borbonense. Los compuestos mayoritarios fueron: P. borbonense (¿-felandreno, 12,43%), P. capense (¿-cadineno, 25,59%,), P. retrofractum (¿-cadineno, 31,63%), P. nigrum ((E)-ß-cariofileno, 22,88%), P. dioica (eugenol, 48,93%), L. neesiana (miristicina, 14,13%), R. chalepensis (2-undecanona, 64,93%), S. therebenthifolia (¿-3-careno, 29,21%), Z. armatum (linalool, 53,30%); Z. bungeanum (linalool, 64,09%). Todo esto muestra las diferencias en el metabolismo secundario de las pimientas y por tanto sus posibles aplicaciones en diferentes industrias.

Currently there is great interest in exploitation of agrofood by-products, such as those from legumes, as source of bioactive ingredients. To that aim, characterization of cyclitol and sugar composition of pods and seeds from different legume species has been carried out. A green Microwave Assisted Extraction (MAE) method was optimized for extraction of bioactive inositols, and both pod and seed yields were compared with those obtained by conventional reflux extraction. A subsequent Saccharomyces cerevisiae treatment was also evaluated for removal of interfering coextracted sugars. myo-Inositol was present in all legume pods and seeds and galactinol in most seeds. chiro-Inositol was found in soybean and basul, whereas outstanding pinitol concentrations were only detected in soybean. The optimized MAE method provided extracts rich in pinitol from soybean pods (41.5–58.0 mg g) and seeds (5.3–7.5 mg g). Removal of 97% of interfering sugars in MAE soybean pod extracts was achieved by yeast treatment.

Five commercial ionic liquid (IL) columns have been evaluated for the first time for the gas chromatography-mass spectrometry (GC-MS) analysis of low molecular weight carbohydrate (LMWC) standards (mono-, di-, and trisaccharides, inositols, and iminosugars). A previous derivatization step was necessary to convert the LMWCs into their volatile and stable derivatives. Compared with conventional GC stationary phases, such as HP-1 and Supelcowax 10, IL columns have shown a different selectivity in the separation of target compounds. Among the IL columns, only SLB™-IL82 allowed the elution of all the LMWCs studied. Its performance in terms of peak width and asymmetry, evaluated under different oven temperature conditions, was shown to be dependent on the carbohydrate class considered. As an example of application, a SLB™-IL82 column was successfully used to separate the complex mixtures of LMWCs in hyacinth and mulberry extracts. This column is an interesting alternative to the conventional stationary phases used in the GC analysis of LMWCs in real-world samples. [Figure not available: see fulltext.].

Novel methodologies for the improved extraction of bioactive carbohydrates that fulfill the principles of green chemistry have been reviewed in this manuscript. As an alternative to conventional water extraction methods, advantages of the use of new green solvents such as ionic liquids and deep eutectic solvents have been discussed. Recent applications of advanced techniques such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), supercritical fluid extraction (SFE) and enzyme-assisted extraction (EAE) have also been revised. Special attention has been paid to those procedures based on the combination of several of these techniques which provide a better performance [e.g. ultrasound-microwave-assisted extraction (UMAE)] or show an improved selectivity [e.g. microwave-assisted aqueous two-phase extraction (MAATPE), microwave-assisted enzymatic extraction or enzymolysis-ultrasound-assisted extraction (MAEE or EUAE), etc.]. Finally, future perspectives regarding the possible application of these new eco-friendly methodologies at industrial scale together with the advances required to that aim are presented.

Honey aroma, which depends on its volatile composition, is one of its most appreciated properties and a subject of great interest in apiculture, as it often determines honey selection by consumer. The wide number of honeys from different botanical source (unifloral, multifloral and honeydew honeys) marketed nowadays makes difficult their characterization for authentication purposes, or to increase their added value in the case of honeys with protected designation of origin. In this sense, the development of fast, reproducible and non-biased methodologies based on Direct Injection Mass Spectrometry could be an approach worthy of evaluation. Whereas methodologies based on Solid Phase Microextraction (SPME) followed by/coupled to Gas Chromatography-Mass Spectrometry (GC-MS) have been previously reported for authentication of honey botanical origin as far as we know, only a previous reference has addressed the botanical discrimination and classification of honey samples based on mass spectral fingerprints collected by SPME.

A new microwave-assisted extraction (MAE) method using ethanol as solvent has been optimized by means of a Box-Behnken experimental design for the enhanced extraction of bioactive terpenoids from Mentha rotundifolia leaves; 100°C, 5 min, 1.125 g dry sample: 10 mL solvent and a single extraction cycle were selected as optimal conditions. Improved performance of MAE method in terms of extraction yield and/or reproducibility over conventional solid-liquid extraction and ultrasound assisted extraction was also previously assessed. A comprehensive characterization of MAE extracts was carried out by GC-MS. A total of 46 compounds, mostly terpenoids, were identified; piperitenone oxide and piperitenone were the major compounds determined. Several neophytadiene isomers were also detected for the first time in MAE extracts. Different procedures (solid-phase extraction and activated charcoal (AC) treatment) were also evaluated for clean-up of MAE extracts, with AC providing the highest enrichment in bioactive terpenoids. Finally, the MAE method here developed is shown as a green, fast, efficient and reproducible liquid extraction methodology to obtain M. rotundifolia bioactive extracts for further application, among others, as food preservatives.

Its high resolution and sensitivity make of gas chromatography (GC) one of the most useful techniques for assessment of food authenticity. In this chapter, fundamentals and instrumentation of GC, together with several outstanding applications aimed to determine the authenticity of foodstuffs at more risk (e.g. fats and oils, dairy products, honey, coffee, spices, fruit juices, and wines) are covered. The coupling of GC to mass spectrometry (GC-MS) affords valuable structural information for reliable identification of authenticity markers and/or to get insight into the adulterants employed. Moreover, the potential of comprehensive two-dimensional gas chromatography (GC×GC) for resolving the complex mixtures involved in most common food frauds and for detection of subtle adulterations is also discussed.