Extraction of Diterpene-Phytochemicals in Raw and Roasted Coffee Beans and Beverage Preparations and Their Relationship.

Cafestol and kahweol are expressive furane-diterpenoids from the lipid fraction of coffee beans with relevant pharmacological properties for human health. Due to their thermolability, they suffer degradation during roasting, whose products are poorly studied regarding their identity and content in the roasted coffee beans and beverages. This article describes the extraction of these diterpenes, from the raw bean to coffee beverages, identifying them and understanding the kinetics of formation and degradation in roasting (light, medium and dark roasts) as the extraction rate for different beverages of coffee (filtered, Moka, French press, Turkish and boiled). Sixteen compounds were identified as degradation products, ten derived from kahweol and six from cafestol, produced by oxidation and inter and intramolecular elimination reactions, with the roasting degree (relationship between time and temperature) being the main factor for thermodegradation and the way of preparing the beverage responsible for the content of these substances in them.

Cuidado e gratidão em relatos de parto de sites ingleses / Care and gratitude in birth stories in English websites

Resumo Neste trabalho, examino as percepções de mulheres sobre o cuidado recebido no parto através da presença ou ausência da gratidão em relatos de parto de dois sites ingleses. Nos relatos, nem sempre a gratidão é expressa e nem sempre ela se dirige à equipe de saúde - agradece-se às doulas ou aos próprios sites, cujos vídeos de preparação para o parto teriam sido importantes para uma experiência positiva. O bom cuidado no parto nesses relatos está associado a uma boa comunicação entre parturiente e midwife (parteira), especialmente nas informações recebidas sobre os procedimentos e sobre o que fazer ao longo do trabalho de parto. Assim, tanto nesses relatos quanto na literatura de saúde pública sobre o parto, a boa equipe é aquela que dá à mulher condições de tomar suas próprias decisões, de fazer suas escolhas informadas. Ao fazê-lo, empodera a mulher e reduz a assimetria na relação entre profissional e paciente. Ao contrário, informações contraditórias ou pouca informação podem produzir ansiedade e desconforto. Argumento, assim, que o sentimento de gratidão, ausente ou presente nos relatos de parto, ilumina as dinâmicas da assistência ao parto na Inglaterra, revelando o que se constitui um bom cuidado.

Abstract In this paper, I examine women´s perceptions of birth care through the presence or absence of gratitude in birth stories from two English websites. In these narratives, gratitude is not always expressed nor is it necessarily addressed to the health team - doulas or the websites themselves are thanked for helping prepare for childbirth and for a positive experience. Good birth care in these stories is associated with good communication between women and midwife, especially regarding the information they receive about the procedures and about what to do during labor. Thus, both in these narratives and in the public health literature on childbirth, a good care team is one that enables women to make their own decisions and informed choices. In doing so, it empowers women and reduces asymmetry in the professional-patient relationship. On the contrary, contradictory or little information can produce anxiety and discomfort. Therefore, I argue that the feeling of gratitude, absent or present in birth reports, illuminates the dynamics of childbirth care in England, revealing what constitutes good care.

Agência e poder na pesquisa: algumas reflexões sobre os termos de consentimento livre e esclarecido / Agency and power in research: some thoughts about informed consent forms

Resumo Neste artigo, discutimos algumas premissas do termo de consentimento livre e esclarecido (TCLE), partindo do princípio que elas não são dadas. Argumento que o uso de um termo de consentimento deve ser compreendido dentro de uma relação de pesquisa, que é ao mesmo tempo uma relação intersubjetiva entre duas ou mais pessoas posicionadas socialmente. Desenvolvo esta reflexão a partir de minhas experiências recentes de pesquisa antropológica sobre gestação e parto, nas quais apresentei um TCLE em duas etapas do estudo, mas não em uma intermediária, que se dedicava a explorar mais as relações familiares durante a gravidez do que a experiência corporal em si. Assim, comparando essas três situações, examino suas especificidades na obtenção do consentimento, para discutir as dimensões de agência, poder e ética na pesquisa social.

Abstract This article discusses some premises that constitute informed consent forms, assuming they should not be taken for granted. I argue that the use of informed consent forms should be understood within a research relationship, which is always an intersubjective relation between two or more socially positioned individuals. I develop these reflection based on my recent experiences of anthropological research on pregnancy and birth, during which I used an informed consent form in two stages but not in an intermediary phase, which was dedicated to focus on kinship relations during pregnancy more than the bodily experience itself. Thus, by comparing these three situations, I examine their particularities in obtaining consent, discussing agency, power, and ethics in social research.

Heteromorphic stamens are differentially attractive in Swartzia (Fabaceae).

The division of labour hypothesis between stamens has explained the evolution of divergent functions between dimorphic stamens in the same flower. However, little is known about whether the distinct type of stamens differs in attractiveness to pollinators. Therefore, we investigate whether the two types of stamens commonly found in Swartzia have different visual and olfactory attractants. We performed observations of anthesis dynamics, registration and collection of floral visitors, measurements of reflectance of floral parts and chemical analysis of the volatile organic compounds of the floral parts of two species, S. flaemingii and S. simplex. Both species have two distinct sets of stamens: one with smaller and abundant stamens in the centre of the flower and the other with fewer but larger abaxial stamens. The sets differ in UV reflectance (only S. simplex) and exhibit a distinct chromatic contrast. Concerning olfactory attractiveness, aliphatic compounds make up most of the odour of the two species, both whole flowers and most of their floral organs. On the other hand, only S. simplex presented apocarotenoids (as ionones) and benzenoids. Furthermore, there are differences in the proportion of volatiles emitted by the stamen in both cases, as the high proportion of sesquiterpenes among the smaller stamens compared to the larger ones. In conclusion, the two types of stamens found in S. flaemingii and S. simplex show a distinct attractiveness. In addition, our data have demonstrated diverse ways of differential attractiveness both between distinct stamens set per flower and between the two species from the same pollen flowers genus.

TLC-ESI-MS as a QuEChERS approach to detection of capsaicin present in different matrices.

Pepper is one of the most consumed spices in the world. Its main compound is capsaicin, a widely studied biomarker that has pharmacological activities due to its anti-inflammatory and analgesic capacity. Topical formulations such as patches based on capsaicin have been developed as an option in relieving pain and reducing swelling. In addition, capsaicin is used as an active ingredient in non-lethal weapon formulations such as pepper spray through the QuEChERS concept (Quick, Easy, Cheap, Effective, Robust, Safe) technique. Used for food analysis, it allows the direct analysis of the biomarker by TLC-ESI-MS, which are previously separated by HPTLC (High Performance Thin Layer Chromatography) using an internal standard for determination of Rf and confirmation of capsaicin in different matrices.[Formula: see text].

Políticas de saúde, confiança e afeto em narrativas de parto / Health policies, trust and affect in birth narratives / Políticas de salud, confianza y afecto en las narrativas de parto

Resumo O Programa de Humanização do Pré-Natal e do Nascimento (PHPN) foi instituído pelo Ministério da Saúde no Brasil em 2000, com o propósito de assegurar o respeito à mulher e ao bebê e diminuir práticas intervencionistas desnecessárias. No entanto, em narrativas de parto com mulheres usuárias do sistema privado de saúde no Rio de Janeiro, coletadas em 2016, houve pouca menção às diretrizes deste programa. A preocupação em encontrar um médico que realize parto normal e respeite as vontades da paciente está presente, mas o desenrolar do parto é entendido como confirmando ou não uma relação pessoalizada de confiança entre médico e paciente, e não como um conjunto de direitos que as parturientes têm e que os obstetras devem observar. Analiso então como este entendimento se manifesta através das categorias emotivas usadas nas narrativas.

Abstract The Prenatal and Birth Humanization Program was instituted by the Brazilian Health Ministry in 2000, aiming at ensuring respectful attention to women and babies and diminishing the use of unnecessary medical interventions. However, among women who had private health plans in Rio de Janeiro and who were interviewed in 2016, there were few mentions to this program's guidelines. They attempted to find obstetrician who perform normal births and respect women´s wishes, but they understood the development of birth as confirming or not a personalized trust relationship between doctor and patient, rather than resulting from rights that should be observed. Thus, I analyze how this understanding is revealed through the emotion categories used in the birth narratives.

Resumen El Programa de Humanización del Pré-Natal y del Nacimiento (PHPN) fue instituido por el Ministerio de Salud de Brasil en el año 2000, con el propósito de asegurar el respeto hacia las mujeres y hacia los bebés y reducir las prácticas intervencionistas innecesarias. Sin embargo, en los relatos de partos con mujeres usuarias del sistema privado de salud en Río de Janeiro, recopilados en 2016, se mencionaron poco las directrices de este programa. La preocupación por encontrar un médico que realice el parto normal y respete los deseos de la paciente está presente, pero el desarrollo del parto se entiende como la confirmación o no de una relación personalizada de confianza entre el médico y la paciente, y no como un conjunto de derechos que las gestantes en trabajo de parto tienen y que los obstetras deben observar. Analizo entonces cómo este entendimiento se manifiesta a través de las categorías emocionales utilizadas en las narraciones.

Metabolic study of cafestol using in silico approach, zebrafish water tank experiments and liquid chromatography high-resolution mass spectrometry analyses.

Coffee is one of the most consumed beverages worldwide. Cafestol is an endogenous coffee diterpene present in raw coffee beans and also found in hot beverages, with several biological activities. However, there is still little information on this molecule after ingestion of coffee infusion. Zebrafish (Danio rerio) is a promising in vivo model for metabolic studies due to the annotation of mammalian orthologs to encode enzymes related to drug metabolism. Experiments using Zebrafish Water Tank (ZWT) model produce more significant number of metabolites for molecular investigation in a cleaner matrix than other classical models, such as purified hepatocytes. This work aimed to investigate the biotransformation of cafestol by the ZWT model using ultra-performance liquid chromatography coupled to hybrid quadrupole-orbitrap high-resolution mass spectrometry equipped with electrospray ionization (UPLC-HRMS) supported by in silico approach using SMARTCyp, Way2Drug and XenoSite Softwares. Twenty-five metabolites of cafestol were proposed by in silico analysis, in which 5 phase I metabolites were confirmed in the ZWT by UPLC and MS/HRMS investigation: 6-hydroxy-cafestol, 6,12-dihydroxy-cafestol, 2-oxo-cafestol, 6-oxo-cafestol and one isomer whose position in the carboxyl group was not determined. These metabolites were observed during 9 h of the experiment, whose contents were associated with the behavioral responses of the fish.

Characterization of ßN-Octadecanoyl-5-hydroxytryptamide Anti-Inflammatory Effect.

BACKGROUND: N-octadecanoyl-5-hydroxytryptamide (C18-5HT) is an amide that can be obtained by the coupling of serotonin and octadecanoic acid. This study aims to characterize the in vivo and in vitro anti-inflammatory activity of C18-5HT. METHODS: A subcutaneous air pouch model (SAP) was used. The exudates were collected from SAP after carrageenan injection to assess cell migration and inflammatory mediators production. RAW 264.7 cells were used for in vitro assays. RESULTS: C18-5HT significantly inhibited leukocyte migration into the SAP as well as nitric oxide (NO) and cytokines production and protein extravasation. We also observed an reduction in some cytokines and an increase in IL-10 production. Assays conducted with RAW 264.7 cells indicated that C18-5HT inhibited NO and cytokine produced. CONCLUSIONS: Taken together, our data suggest that C18-5HT presents a significant effect in different cell types (leukocytes collected from exudate, mainly polumorphonuclear leukocytes and cell culture macrophages) and is a promising compound for further studies for the development of a new anti-inflammatory drug.

Two New ßN-Alkanoyl-5-Hydroxytryptamides with Relevant Antinociceptive Activity.

In this work, we describe a new route for the synthesis and the antinociceptive effects of two new ßN-alkanoyl-5-hydroxytryptamides (named C20:0-5HT and C22:0-5HT). The antinociceptive activities were evaluated using well-known models of thermal-induced (reaction to a heated plate, the hot plate model) or chemical-induced (licking response to paw injection of formalin, capsaicin, or glutamate) nociception. The mechanism of action for C20:0-5HT and C22:0-5HT was evaluated using naloxone (opioid receptor antagonist, 1 mg/kg), atropine (muscarinic receptor antagonist, 1 mg/kg), AM251 (cannabinoid CB1 receptor antagonist, 1 mg/kg), or ondansetron (5-HT3 serotoninergic receptor antagonist, 0.5 mg/kg) 30 min prior to C20:0-5HT or C22:0-5HT. The substances both presented significant effects by reducing licking behavior induced by formalin, capsaicin, and glutamate and increasing the latency time in the hot plate model. Opioidergic, muscarinic, cannabinoid, and serotoninergic pathways seem to be involved in the antinociceptive activity since their antagonists reversed the observed effect. Opioid receptors are partially involved due to tolerant mice demonstrating less antinociception when treated with both compounds. Our data showed a quicker and simpler route for the synthesis of the new ßN-alkanoyl-5-hydroxytryptamides. Both compounds demonstrated significant antinociceptive effects. These new compounds could be used as a scaffold for the synthesis of analogues with promising antinociceptive effects.

Comprehensive lipid analysis of green Arabica coffee beans by LC-HRMS/MS.

Lipids play an important role in coffee bean development, coffee brew and in the effects of coffee on human health. They account for around 17% of the dry bean weight and encompass different classes and subclasses, mostly triacylglycerols (TAG) and a minor quantity of phospholipids (PL) and ßN-alkanoyl-5-hydroxytryptamides (C-5HT). To comprehensive profile these different lipids, it is important to evaluate extraction methods that provide high lipid coverage and to analyze the lipids in high-resolution techniques. In this work, liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) was employed to comprehensive profile lipids from green Arabica coffee beans and to evaluate the extraction efficiency and lipid coverage of three methods: Bligh-Dyer (BD), Folch (FO), and Matyash (MA). The MA method yielded the greatest number of annotated compounds (131 lipids) compared to the other methods. In the positive electrospray ionization (ESI) mode, the main difference among extraction methods was observed for TAG and diacylglycerols, whereas for the negative ESI it was observed differences for phosphatidylinositol (PI), lysophosphatidylinositol and phosphatidic acid (p < 0.05). The analysis of coffees from different maturation stages and/or post-harvest processes were also performed using the MA method. Immature beans were discriminated from mature and overripe beans by its lower levels of C-5HT, PI, phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, and lysophosphatidylethanolamine. These results can help to better understand the coffee lipid composition and its association with coffee quality.

Fast and Highly Selective Continuous-Flow Catalytic Hydrogenation of a Cafestol-Kahweol Mixture Obtained from Green Coffee Beans.

This work investigates batch and continuous-flow heterogeneous catalytic hydrogenation of a mixture of cafestol and kahweol (C&K) to obtain pure cafestol. These diterpenes were extracted from green coffee beans, and hydrogenation was performed using well-established palladium catalysts (Pd/C, Pd/CaCO3, Pd/BaSO4, and Pd/Al2O3) and a carbon black-supported Pd catalyst coated by a covalently tethered SiO2 shell with mesoporous texture (Pd/CB@SiO2), all partially deactivated with quinoline. Pd/C 10% poisoned with 1 wt % quinoline gave the best result for batch reaction, producing cafestol from kahweol with high selectivity (>99%) after 10 min. Excellent selectivity was also obtained with the catalyst Pd/CB@SiO2 with only 1% Pd. In addition, Pd/C-quinoline adapted for continuous-flow experiments exhibited the best catalytic activity, also providing cafestol with excellent selectivity (>99%) after 9.8 s.

Production of bioactive films of carboxymethyl cellulose enriched with green coffee oil and its residues.

Carboxymethyl cellulose (CMC)-based films were developed by incorporating green coffee oil (GCO) obtained by cold pressing and hydroalcoholic extracts of its residues. The effect of cake (CE) and sediment extracts (SE) in different proportions (20-40%) and GCO on chemical, morphological, physical, mechanical, optical, and antioxidant properties of the films was investigated. Eight fatty acids and four major phenolic compounds were identified by High-Resolution Direct-Infusion Mass Spectrometry in GCO and residue extracts. FTIR indicated interactions among CMC, phenolic compounds, and fatty acids. Films enriched with residue extracts presented heterogeneous microstructure. The tensile strength of the films decreased from 58 to 3 MPa with the extracts concentration, while elongation increased from 28 to 156% (p < 0.05). The water vapor permeability (averaging 3.94 × 10-8 g mm/cm2 h Pa) was not significantly affected by the extracts and GCO. The surface color was influenced by the type and concentration of extracts (p < 0.05), the film with SE40% had remarkable UV-vis barrier properties. The incorporation of GCO residue extracts imparted high antioxidant capacity to the CMC-based films, especially with CE40% (643.8 µmol Trolox eq./g dried film; 51.3 mg GAE/g dried film). General observations indicated the potential of these films, mainly the ones containing CE, like active packaging material for food applications.

Dynamics of volatile compounds in TSH 565 cocoa clone fermentation and their role on chocolate flavor in Southeast Brazil.

The effects of indigenous fermentation on volatile compound profiles in a Theobroma cacao L, TSH565 clone, resistant to Moniliophtora perniciosa and Phytophthora spp. were evaluated in Southern Brazil. Sixty-three volatile flavor compounds in pulp and 36 in grains were identified by SPME-HS/GC-MS and classified as terpenes, alcohols, esters, ketones and aldehydes, among others. The relative amount of these compounds and their evolution until the end of the fermentation process were assessed in both fresh and fermented grains/pulp masses. ß-myrcene and ß-cis-ocimene, among terpenes, were detected in high amounts and are associated to a fine chocolate aroma. The sensory evaluation of chocolates manufactured from the fermented cocoa was performed by trained panelists, which defined 15 sensory descriptors. Chocolates from the TSH565 cultivar were characterized by a rich, fruity, intense cocoa flavor and bitterness, which are valuable sensorial and commercial attributes.

New approaches to monitor semi-volatile organic compounds released during coffee roasting using flow-through/active sampling and comprehensive two-dimensional gas chromatography.

A novel dynamic approach is described to profile volatile organic compound (VOC) and semi-VOC (SVOC) emission during coffee roasting aimed at analysing components present in the roasting plume, and to monitor their evolution during the process. Two sorbents - coconut shell charcoal (CSC) and styrene-divinylbenzene resin (XAD-2) - were evaluated while collecting substances in four sequential time intervals (0-3, 3-6, 6-9 and 9-12 min). Extracted VOCs (<200 Da) and SVOCs were analysed by gas chromatography (GC), and comprehensive two-dimensional gas chromatography (GC × GC) with flame ionisation (FID) and time-of-flight mass spectrometry (TOFMS) detection. Results showed CSC extraction presented poor recovery of VOCs and SVOCs released during roasting. However, XAD-2 was able to collect both groups, including SVOCs of >400 Da. GC × GC resolved many co-eluting compounds observed in 1D GC and allowed chemical group type cluster analysis, revealing that many non-polar VOCs are observed within the 0-3 min interval, and that the release of polar and higher molar mass SVOCs were mostly found within the 3-6 min interval. These group-type cluster analyses offer a broad spectrum chemical profile of the released substances. It may also reveal detailed insights into the roast process evolution over time.

Gas chromatography-mass spectrometry of sapucainha oil (Carpotroche brasiliensis) triacylglycerols comprising straight chain and cyclic fatty acids.

Sapucainha oil, which may be used to treat leprosy, comprises straight chain and cyclic fatty acids (FA), and triacylglycerols (TAG). The FA and TAG content of the oil sample was analysed using gas chromatography-electron ionisation mass spectrometry (GC-EIMS). FA analysis was performed after derivatisation to fatty acid methyl esters (FAME). For free FA and TAG analysis, the oil sample was dissolved in hexane and injected into a short, high-temperature column, for GC with MS analysis. Free FA and FAME were tentatively identified based on mass spectrum information of their molecular and fragment ions, as well as library matching. Overlapping TAG peaks were deconvoluted based on mass fingerprint data. The FA composition was utilised to predict possible TAG identities. FA residues of TAG were identified based on characteristic fragment ions, such as [M-RCO2]+, [RCO+128]+, [RCO+74]+ and RCO+ where R is the aliphatic hydrocarbon chain. FAME analysis showed that the cyclic FA hydnocarpic (36.1%), chaulmoogric (26.5%) and gorlic (23.6%) acids were the major components. In addition, straight chain FA such as palmitic, palmitoleic, stearic, oleic and linoleic acids were detected. Palmitic, oleic, hydnocarpic, chaulmoogric and gorlic acids were also detected as free FA in the oil sample. Six groups of TAG peaks were eluted from GC at temperatures ≥330 °C. After deconvolution and mass spectrum analysis, each TAG peak group was revealed to comprise 2 to 5 co-eluted TAG molecules; >18 TAG were identified. These TAG consisted of a mix of both cyclic and straight chain FA, but were mostly derived from cyclic FA.

Reduction of ßN-alkanoyl-5-hydroxytryptamides and diterpenes by yeast supplementation to green coffee during wet processing.

Coffee is one of the most consumed non-alcoholic beverages in the world. It is well known that some compounds present in coffee beans have important biological activities. In this study, evidence was turned to ßN-alkanoyl-5-hydroxytryptamides (C-5HTs) and to the furokaurane diterpenes cafestol and kahweol, associated with gastric irritation and increasing of blood cholesterol, respectively. Fermentation in coffee post-harvest wet process was induced by three Saccharomyces cerevisiae yeasts (for bakery, white and sparkling wines) as starter cultures. Variations in mass, time, temperature and pH (56 experiments under fractional factorial and mixture experimental designs) were tested. Substantial reductions for C-5HTs (up to 38% reduction for C20-5HT and 26% for C22-5HT) as well as for diterpenes (54% for cafestol and 53% for kahweol) were obtained after treating green coffee beans with 0.6 g of a 1:1:1 mixture the three yeasts for 12 h at 15 °C and pH 4. Caffeine and 5-CQA content, monitored in the green coffee beans, did not change. Therefore, the use of starter cultures during coffee post-harvest wet process has influence on the amount of some important compounds related to health and improves the sensory quality of the beverage.

New ßN-octadecanoyl-5-hydroxytryptamide: antinociceptive effect and possible mechanism of action in mice.

The present study examined the potential antinociceptive activity of C18 5-HT (ßN-octadecanoyl-5-hydroxytryptamide) using chemical and thermal nociception models in mice. Orally administered C18 5-HT (0.1, 1 and 10 mg/kg) produced significant dose-dependent antinociceptive effects in formalin-, capsaicin- and glutamate-induced licking models. This compound also induced a significant increase in the response to thermal stimuli in the hot plate test, and its antinociceptive effect was not related to muscle relaxant or sedative actions. In a thermal hyperalgesia model, C18 5-HT presented an anti-hyperalgesic profile as evidenced by the increase in the response time of the animals. Furthermore, intraperitoneal (i.p) pretreatment with naloxone (a non-selective opioid receptor antagonist, 1 mg/kg), ondansetron (serotoninergic receptor antagonist (5-HT3 subtype), 0.5 mg/kg) or AM241 (CB1 cannabinoid receptor antagonist, 1 mg/kg) reversed the antinociceptive effects of C18 5-HT in the hot plate model. In the formalin-induced licking model, pretreatment with naloxone reversed the antinociceptive effects of C18 5-HT, as demonstrated by an increase in the paw licking response when compared with the C18 5-HT-treated group. These findings suggest that C18 5-HT has peripheral and central antinociceptive effects and that its mechanism of action involves, ate least in part, opioid, serotoninergic and cannabinoid pathways.

Lipase-catalysed esters synthesis of cafestol and kahweol.

Cafestol and kahweol (C&K), two coffee diterpene alcohols with structural similarity which exhibit anticarcinogenic effects, were isolated from green coffee Arabica beans, followed by their lipase-catalysed esterification and purification by preparative high-performance liquid chromatography (HPLC). The isolation and enzymatic synthesis parameters of C&K esters were studied, with the latter optimised by a Central Composite Design; both procedures were monitored by gas chromatography. Scale up and improved isolation conditions resulted in 1.29 g of C&K, with 98% purity from 300 g of green Arabica beans. The highest C&K ester yields were observed using an alcohol:fatty acid molar ratio of 1:5, 73.3 mg mL-1 of CAL-B enzyme, 70 °C and 240 rpm for 3 days in toluene, leading to 85-88% conversion among a variety of tested C&K esters, including n-C14:0-C20:0, C18:1, C18:2 and C18:3.

Analysis of underivatised low volatility compounds by comprehensive two-dimensional gas chromatography with a short primary column.

Comprehensive two-dimensional gas chromatography (GC×GC) approaches with cryogenic modulation were developed for the qualitative analysis of selected low volatility compounds in raw coffee bean extracts, without derivatisation. The approaches employed short first (1D) and second (2D) dimension columns, specifically a 1D 65% phenyl methyl siloxane column (11m) and a 2D 5% phenyl methyl siloxane column (1m), which allowed elution of high molar mass compounds (e.g.>600Da). Solutes included hydrocarbons, fatty acids, diterpenes, tocopherols, sterols, diterpene esters, and di- and triacylglycerides. An oven temperature program up to 370°C was employed. The effects of experimental conditions were investigated, revealing that the GC×GC results strongly depended on the cryogenic trap T, and oven T program. An appropriate condition was selected and further applied for group type analysis of low volatility compounds in green Arabica coffee beans. Retention indices were compiled for 1D GC analysis and were similar for the composite column data in GC×GC. The elution of some compounds was confirmed by use of authentic standards. The approach allowed direct analysis of coffee extract in ethyl acetate solution, with improved analyte peak capacity (approximately 200 compounds were detected) without prior fractionation or pre-treatment of the sample. This avoided potential hydrolysis of high molar mass conjugate esters as well as degradation of thermally labile compounds such as the derivatives of the diterpenes cafestol and kahweol.

Ionic liquid capillary columns for analysis of multi-component volatiles by gas chromatography-mass spectrometry: performance, selectivity, activity and retention indices.

This study investigates applications and performance evaluation of SLB-IL60, SLB-IL76 and SLB-IL111 columns, in relation to a DB-Wax column, for the analysis of coffee volatile compounds. Both standards and an authentic coffee sample were analysed, with solid-phase microextraction (SPME) sampling of the latter. A cryofocusing method was applied to improve resolution of the earliest eluting peaks using splitless injection SPME sample analysis. The Grob test was used to verify the inertness and efficiency of the columns, helping to understand the interactions between analytes and stationary phases, particularly toward more polar coffee analytes. A DB-5 column was used only in analysis of n-alkanes and Grob test mixtures as an apolar reference. The evaluated ionic liquid columns showed a moderate acid-base character and low inertness for compounds with hydrogen bond capabilities, especially for the hydroxylated analytes, 2,3-butanediol in the Grob test, and furanones and acids in the coffee standards. The columns exhibiting the best resolution and efficiency were DB-Wax and SLB-IL60, both for samples and standards. Although the DB-Wax column is preferred for analysis of coffee volatiles, due to better inertness, the evaluated ionic liquid columns allowed identification of compounds that were not observed in separations with the Wax-phase column in this work. Among these compounds is 3,4-dimethyl-2,5-furandione, seldom reported in the literature of coffee. Proposed improvement by the manufacturer in the inertness of the columns evaluated in this study may lead to better results; so future versions of IL phases may be better applied in the separation of target analytes, especially those with basic character. Graphical abstract Illustrative representation of the sample (coffee) and the chemical structures of the stationary phases of the ionic liquid capillary columns used as object of study in the present work.