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This work is focused on the study of the metabolomic changes that occur in cocoa powder throughout the alkalization process by using an untargeted ultra high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-QTOF-MS) metabolomics approach. With this aim, cocoa powder samples submitted to different alkalization degrees (light, medium, and strong) were analyzed. Metabolite extraction was performed using 75% MeOH in water since it provided the highest number of molecular features. After data processing, non-supervised and supervised methods were applied to carry out the statistical data analysis. Thus, the most significant metabolites that allow establishing differences among the cocoa powder samples submitted to the alkalization processes were pointed out. Thus, 43 and 30 metabolites in positive and negative ionization modes, respectively, demonstrated to be relevant. Among them, 9 compounds were unequivocally identified and 22 tentatively identified. Most of them were amino acids, alkaloids, organic acids or polyphenols, among others., Authors thank the Comunidad of Madrid and European funding from FSE and FEDER programs for project S2018/BAA-4393 (AVANSECAL-II-CM) and the University of Alcalá for project CCGP2017-EXP/057. M.C.P. thanks MINECO for her “Ramón y Cajal” research contract (RYC-2013-12688). M.G. thanks the Spanish Ministry of Science, Innovation, and Universities for her pre-doctoral contract (FPU17/01635). Authors also thank OLAM for the kind donation of cocoa powder samples.

Trabajo presentado al 4th International Congress on Green Process Engineering celebrado en Sevilla (España) del 7 al 10 de abril de 2014., A. P. S. C thanks to the Administrative Department of Science, Technology and Innovation - COLCIENCIAS - Colombia for her Ph.D fellowship (Doctoral Studies Abroad programme). M.H. would like to thank the Spanish Science and Innovation Ministry (MICINN) for a “Ramon y Cajal” research contract. This work has been financed by the Spanish Ministry of Science (Project AGL2011-29857-C03-01).

This is an open access article distributed under the Creative Commons Attribution License.-- This article belongs to the Special Issue Bioactive Phenolics and Polyphenols., The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals., We are grateful to the Spanish Ministry of Education and Science for Project AGL2011-29857-C03-02, to the Andalusian Regional Government Council of Innovation and Science for Project P11-CTS-7625 and to the GREIB.PT.2011.18 project., We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).

Subcritical water extraction (SWE) is presented in this chapter as a potent and novel alternative to conventional solvent extraction processes for isolating bioactive components from algae. SWE is defined as extraction with water at temperatures ranging from boiling point to the critical temperature and at pressures high enough to keep the water in a liquid state throughout the extraction process. Water has many advantages when used as solvent since it is environmentally friendly and sustainable, and some of its physical and chemical properties can be modified by heating. This chapter discusses interesting current applications of this technology as well as the potential of other applications which could be successfully developed under SWE conditions.

Trabajo presentado a la III Iberoamerican Conference on Supercritical Fluids celebrada en Cartagena de Indias (Colombia) del 1 al 5 de abril de 2013., Rosemary (Rosmarinus officinalis, L.) is an aromatic plant widely known by its antioxidant properties. This bioactivity is correlated with the presence of two chemical families of compounds: phenolic terpenes (carnosic acid, carnosol…) and flavonoids (rosmarinic acid). Pressurized Liquid Extraction (PLE) using ethanol and water has proved to be one of the main techniques for the isolation of those compounds, while other green extraction techniques such as SFE and PHWE (Pressurized Hot Water Extraction) provide extracts mainly enriched in one family of compounds. The objective of the present work was to develop a continuous method for the fractionation of PLE extracts in different families of bioactive compounds. To do this, a self-designed equipment was set up. In this system the fractionation of phenolic terpenes and flavonoids took place mediated by the antisolvent effect of supercritical CO2 in the ethanol:water mixture. The optimization of the process was carried out using a response surface methodology (RSM) based in two factors: CO2 Pressure and ratio (CO2:PLE extract) flow rate, using 3 levels per factor. The selected responses for the optimization were the relative amount of each compound (rosmarinic and carnosic acids and carnosol) in the vessels. Those compounds were quantified using HPLC-UV-ESI-MS. The RSM allowed the optimization of the process by providing a mathematical model with a very high correlation with experimental data. Moreover the system developed can be used as green preparative technique for further fractionations, without the need of using tedious preparative LC steps, because it can be run in continuous mode., This work was financed thanks to AGL2011-29857-C03-01 (Ministerio de Economía y Competitividad) project. M.C.P. thanks MICINN for her “Juan de la Cierva” contract. M.H. would like to thank MICINN for a “Ramón y Cajal” research contract.

Trabajo presentado al XXII Congreso Italo-Latinoamericano de Etnomedicina celebrado en Puntarenas (Costa Rica) del 2 al 6 de septiembre de 2013., At present, there is an enormous interest in finding new bioactive compounds able to prevent or improve the health status of the individuals, mainly acting as food supplements, nutraceuticals or functional food ingredients. Undoubtedly, nature can be considered an unlimited source of bioactives and the search of new compounds with improved activities have ran parallel to the search for new natural sources. Different families of compounds have been extracted from plants, although nowadays there is a huge interest in the potential use of marine natural sources to obtain these bioactives, mainly considering their huge diversity, in terms of number of different species that might be potentially used, their sometimes unique chemical structures and their ability to work as natural bioreactors potentiating the synthesis of valuable compounds depending on the cultivation conditions. Moreover, researchers are facing new challenges in the optimization of new extraction processes to obtain bioactives from natural sources: the development of fast, selective, efficient, sustainable, green (without using toxic organic solvents), with high yields and at lower cost extraction processes is a must. The techniques able to meet these requirements are, among others, those based on the use of compressed fluids such as supercritical fluid extraction (SFE), pressurized liquid extraction (PLE) and subcritical water extraction (SWE), which are among the more promising processes. In this presentation, different examples will be shown, considering different raw materials such as plants, algae and food by-products and employing these sustainable green technologies. With this approach we will try to demonstrate the possibility of tuning the extraction conditions depending on the target compound(s) and the raw material., This work was financed thanks to AGL2011-29857-C03-01 (Ministerio de Economía y Competitividad) and ALIBIRD, S2009/AGR-1469 (Comunidad de Madrid) projects. M.C.P. thanks MICINN for her "Juan de la Cierva" contract. M.H. would like to thank MICINN for a "Ramón y Cajal" research contract.

Trabajo presentado a la III Iberoamerican Conference on Supercritical Fluids celebrada en Cartagena de Indias (Colombia) del 1 al 5 de abril de 2013., In the last years there has been an increasing interest in functional food ingredients due to their capacity to promote our health. Thus, one of the main areas in Food Science and Technology is the extraction and characterization of new bioactive compounds of natural origin. Considering the huge biodiversity of microalgae it is easy to understand that they represent one of the most important biological sources for novel biological compounds. In fact, it has been suggested that secondary metabolites produced by these organisms under certain extreme conditions (temperature, nutrients, UV-vis irradiation), provide with unique structures with important activities for human health such as antioxidant. As an example, beta-carotene and astaxanthin produced by Dunaliella salina and Haematococcus pluvialis respectively, have important application in the nutraceutical market. In the search of new bioactives from microalgae, another important aspect to be considered is the development of fast and environmental-friendly extraction processes to isolate the bioactive compounds. The purpose of this work was to develop a methodology to extract and characterize the carotenoids of N. Oleoabundans to demonstrate for the first time the potential of this microalga as a source of antioxidants. Thus, pressurized liquid extraction (PLE) was optimized by means of an experimental design considering food grade solvents such as ethanol and limonene; the chemical characterization of the extracts was carried out by means of HPLC-MS. The main carotenoids accumulated by the microalgae were lutein, cantaxanthin, zeaxanthin, or monoester and diester of astaxanthin., This work was financed thanks to AGL2011-29857-C03-01 (Ministerio de Economía y Competitividad (MINECO)) and ALIBIRD, S2009/AGR-1469 (Comunidad de Madrid) projects. M.C.P. and M.H. would like to thank MINECO for their respective “Juan de la Cierva” and “Ramón y Cajal” research contracts.

Trabajo presentado al 10th International Symposium on Supercritical Fluids celebrado del 13 al 16 de mayo de 2012 en San Francisco (US)., Subcritical water extraction (SWE) has demonstrated a great potential for the extraction of bioactive compounds from natural matrices. The application of high extraction temperatures and pressures, while keeping the water in the liquid state, allows the attainment of high extraction yields in fast extraction processes. Although the applications of SWE to obtain bioactives from natural matrices are increasing, the studies dealing with the processes that might take place during the extraction are still scarce. Recently, we demonstrated how under SWE conditions not only the solubility of the analytes might be improved but also neoformed antioxidants can be obtained. Indeed, it was observed how the occurrence of reactions like Maillard and caramelization reactions during SWE resulted on the formation of neoantioxidants. This fact can be advantageous although the possible toxicity of the compounds formed during these non-enzymatic reactions should be carefully considered. Formerly, we observed that during the extraction of olive tree leaves at high extraction temperatures (200ºC), more active extracts in terms of antioxidant and in-vitro antiproliferative activities were obtained. Chemical characterization of those extracts revealed not only the presence of phenolic bioactives but also 5-(hydroxymethyl)furfural (HMF), a compound related to Maillard reaction. For this reason, in this work, a more exhaustive study has been devised to observe the influence of the temperature in the formation of HMF in SWE extracts of olive leaves. The final aim was to determine the relevance of the HMF present on different SWE extracts in terms of bioactivity. Thus, extracts obtained at different extraction temperatures were produced (50, 75, 100, 125, 150, 175 and 200 ºC) and chemically characterized by LC-MS. HMF was quantified in the extracts by HPLC-DAD. Moreover, the antioxidant activity, the amount of total phenols (Folin method) as well as the anticancer activity of both, extracts and HMF standard, were determined., This work was financed thanks to AGL2008-05108-C03-01 and AGL2011-29857-C03-01 (Ministerio de Educacion y Ciencia), CSD2007-00063 FUN-CFOOD (Programa CONSOLIDER-INGENIO 2010) and ALIBIRD, S2009/AGR-1469 (Comunidad de Madrid) projects. M.H. would like to thank MICINN for a “Ramón y Cajal” research contract. M.C.P. thanks MICINN for her “Juan de la Cierva” contract.

Resumen del trabajo presentado a la VI Reunión de Expertos en Tecnologías de Fluidos Comprimidos celebrada en Madrid del 28 al 29 de junio de 2012., Hoy en día, no hay duda de que uno de los aspectos de mayor interés de la Ciencia y Tecnología de los Alimentos es la extracción y caracterización de nuevos ingredientes funcionales que contribuyan a la salud y al bienestar. En este sentido, las algas marinas tienen la capacidad de generar una gran variedad de metabolitos biológicamente activos con estructuras moleculares únicas para sobrevivir en condiciones ambientales extremas como cambios de salinidad, temperatura, variación en la irradiación, etc. Además teniendo en cuenta su gran diversidad taxonómica y bioquímica, se pueden considerar casi como fuentes naturales inagotables de productos activos con propiedades antioxidantes, antivirales, antimicrobianas, anticancerígenas, etc, beneficiosas para la salud. Para la obtención de dichos productos activos, se hace imprescindible el desarrollo de procesos de extracción rápidos, eficientes y medioambientalmente limpios. En el presente trabajo se ha llevado a cabo la extracción con líquidos presurizados (PLE) de los carotenoides de la microalga Neochloris oleoabundans. Como paso previo a la extracción se llevó a cabo el estudio de diferentes tratamientos, tales como ciclos congelación-descongelación, hidrólisis ácida, hidrólisis básica y molienda criogénica, para asegurar la rotura de la pared celular del alga. Los extractos obtenidos bajo las condiciones óptimas de extracción fueron caracterizados químicamente mediante HPLC-MS. Asimismo, se determinó el contenido total de carotenoides de los extractos y la capacidad antioxidante de los mismos., Los autores agradecen la financiación otorgada por el Ministerio de Economía y Competitividad a través del proyecto AGL2011-29857-C03-0134457(2012). M.C.P y M.H. agradecen respectivamente al MICINN sus contratos “Juan de la cierva” y “Ramón y Cajal”.

Póster presentado al XII Scientific Meeting of the Spanish Society of Chromatography and Reated Techniques (Reunión Científica de la Sociedad Española de Cromatografía y Técnicas Afines) celebrado en Tarragona del 14 al 16 de noviembre de 2012., This work was financed thanks to AGL2011-29857-C03-01 (Ministerio de Economía y Competitividad (MINECO) and ALIBIRD, S2009/AGR-1469 (Comunidad de Nadrid) projects. M.C.P. thanks MINECO for her "Juan de la Cierva" research contract. M.H. would like to thank MINECO for his "Ramón y Cajal" research contract.

Resumen del póster presentado a la VI Reunión de Expertos en Tecnologías de Fluidos Comprimidos celebrada en Madrid del 28 al 29 de junio de 2012., El romero (Rosmarinus officinalis, L.) es una planta ampliamente conocida por sus propiedades antioxidantes. Dicho elevado carácter antioxidante se debe principalmente a la presencia de dos tipos de compuestos, por un lado los terpenos fenólicos como el ácido carnósico o el carnosol y por otro lado los flanoides como el ácido rosmarínico. Para la extracción de ambas familias de compuestos la extracción líquidos presurizados (PLE) ha demostrado ser una de las más eficaces, concretamente empleando etanol a 150 ºC. Mientras que empleando otras técnicas de extracción como SFE (con CO2 y etanol) o SWE (con agua a 200ºC) se obtienen extractos enriquecidos sólo en una de las familias de compuestos. El objetivo del presente trabajo es el fraccionamiento de ambas familias de compuestos presentes en un extracto obtenido mediante PLE. Para la realización de dicho fraccionamiento se diseñó un sistema basado en la precipitación mediada por CO2 supercrítico por efecto antisolvente (SAS), Figura. Los factores estudiados para optimizar el fraccionamiento fueron la presión (100-300 atm) y la relación de caudales de alimentación. El estudio de la composición de los extractos se realizó mediante HPLC-DAD-ESI-MS., Los autores agradecen la financiación otorgada por el Ministerio de Economía y Competitividad a través del proyecto AGL2011-29857-C03-0134457(2012). M.C.P y M.H. agradecen respectivamente al MICINN sus contratos “Juan de la cierva” y “Ramón y Cajal”.

Trabajo presentado al 10th International Symposium on Supercritical Fluids celebrado en San Francisco (US) del 13 al 16 de mayo de 2012., Rosemary is one of the most appreciated natural sources for bioactive compounds with different activities such as antioxidant, antimicrobial or anticarcinogenic. Antioxidant activity has been associated to some of its components, among them, phenolic diterpenes such as carnosic acid, carnosol and rosmarinic acid. A careful selection of the extraction process together with the optimization of the extraction conditions, are of high importance to obtain rosemary extracts with high bioactivity. Among the different extraction processes, supercritical fluid extraction (SFE) and pressurized hot water extraction (PHWE) have demonstrated to be the most selective and environmental friendly techniques. However, extracts obtained by these processes usually require a drying step (freeze or hot drying step) which is both energy and time consuming. In this work, a new process combining PHWE and powder formation on-line (water extraction and particle formation on-line process, WEPO®) has been developed to obtain dry antioxidant powder from rosemary leaves in one step. In this process, parameters related to the extraction efficiency and selectivity (water flow rate and temperature) as well as parameters involving spray stability and powder formation have been considered at the same time. The obtained extracts have been evaluated in terms of their antioxidant activity using the DPPH method. Finally, in order to assess the viability and environmental impact of the new process, a comparison with other green processes used for antioxidant extraction from rosemary leaves such as SFE and PHWE (both followed by a freeze drying step) has been performed in terms of Life Cycle Assessment (LCA). Moreover, a sensitivity analysis of the LCA has been carried out to study the different environmental impact between the processes whether they are employed in different countries., This work was supported by AGL2008-05108-C03-01 (Ministerio de Educación y Ciencia), CSD2007-00063 FUN-CFOOD (Programa CONSOLIDER-INGENIO 2010), and S-0505/AGR/000153 (Comunidad Autónoma de Madrid) projects. C.T. acknowledges the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS, 2006-1346); the Swedish Research Council (VR, 2006-4084); and the Swedish Foundation for Strategic Research (SSF, 2005:0073/13, RMA08-0044). M.C-P. thanks MICINN for her “Juan de la Cierva” contract.

Trabajo presentado al XII Scientific Meeting of the Spanish Society of Chromatography and Reated Techniques (Sociedad Española de Cromatografía y Técnicas Afines) celebrado en Tarragona del 14 al 16 de noviembre de 2012.

Resumen del póster presentado a la VI Reunión de Expertos en Tecnologías de Fluidos Comprimidos celebrada en Madrid del 28 al 29 de junio de 2012., La creciente demanda de la industria alimentaria de nuevos alimentos funcionales pone de manifiesto la necesidad de obtener, de una forma segura y sostenible, ingredientes funcionales naturales, que contribuyan al estado de bienestar de los consumidores. Entre las técnicas de extracción, el empleo del agua líquida a elevadas temperaturas (Extracción con Agua Subcrítica, SWE) ha demostrado ser una alternativa para la obtención de compuestos bioactivos, proporcionando elevados rendimientos y selectividades. Dentro de las fuentes naturales, las microalgas pueden ser consideradas como fuentes inagotables de compuestos bioactivos, que se generan bajo condiciones ambientales extremas, y pueden resultar beneficiosos para la salud. Entre los compuestos que pueden encontrarse en las algas, los compuestos polifenólicos son de elevada importancia debido principalmente a su elevada capacidad antioxidante. En el presente trabajo se ha llevado a cabo la SWE de una serie de microalgas inéditas, donadas por el Banco Español de Algas (BEA), con el objetivo de obtener extractos con elevada capacidad antioxidante. Para ello se emplearon diferentes temperaturas de extracción y se midió la capacidad antioxidante y el contenido de fenoles totales de los extractos obtenidos., Los autores agradecen la financiación otorgada por el Ministerio de Economía y Competitividad a través del proyecto AGL2011-29857-C03-0134457. O.A agradece la subvención de movilidad de máster del Ministerio de Educación, Cultura y Deporte y M.C.P y M.H. agradecen respectivamente al MICINN sus contratos “Juan de la cierva” y “Ramón y Cajal”.

Resumen del trabajo presentado al VII Congreso Español de Ingeniería de los Alimentos celebrado en Ciudad Real del 7 al 9 de noviembre de 2012., El uso de subproductos generados en el tratamiento tecnológico de los productos naturales como fuente de ingredientes alimentarios con propiedades bioactivas y antioxidantes es actualmente un área de trabajo de gran interés que ha estimulado la aplicación de diferentes sistemas de extracción y técnicas cromatográficas acopladas a diversos sistemas de detección para el aislamiento y caracterización de los analitos presentes en estas matrices. La producción de aceite de oliva está asociada con la generación de una gran cantidad de subproductos, siendo de entre todos ellos, el menos caracterizado desde un punto de vista de su composición en compuestos bioactivos el generado en el proceso de filtración, el cual puede retener algunos compuestos fenólicos. Los polifenoles del aceite de oliva no sólo están implicados en las características organolépticas y sensoriales, sino que sus propiedades antioxidantes y antiinflamatorias los han relacionado con la prevención de enfermedades cardiovasculares y diferentes patologías cancerosas. En el presente trabajo de investigación, el potencial de los subproductos generados durante la filtración del aceite de oliva como fuente natural de compuestos bioactivos ha sido evaluado usando extracción con fluidos presurizados (PLE) seguido de su análisis mediante cromatografía líquida de alta resolución acoplada a espectrometría de masas de tiempo de vuelo (ESI-TOF/MS).

In this work, the water extraction and particle formation on-line (WEPO) process has been used to obtain dry antioxidant powder from rosemary leaves. This process includes pressurized hot water extraction (PHWE) and on-line drying of the extracts in one step. Based on previous works, water extraction at 200 °C was selected to achieve the maximum antioxidant activity while water flow rate was studied to determine its influence on powder formation. Other parameters influencing the drying process, such as scCO2 pressure (80 bar) and flow rate (2.5 mL/min) and N2 flow rate (0.6 mL/min) were settled to obtain a fine and constant spray. Powders obtained were evaluated in terms of particle size and morphology by scanning electron microscopy (SEM) as well as antioxidant capacity by an in vitro DPPH antioxidant assay. In order to assess the environmental performance of the WEPO process, this has been compared in terms of Life Cycle Assessment (LCA) to other green processes typically used for antioxidant extraction from rosemary leaves, such as supercritical fluid extraction (SFE) and a static pressurized hot water extraction, PHWE, carried out with a commercial equipment, both followed by a conventional drying step. The WEPO process, carried out in one step, giving dry bioactive extracts from rosemary, results in lower environmental impacts and energy consumption than the other green processes studied. The sensitivity assessment demonstrated the importance of primary energy sources in the production of electricity used, especially when green processes are being implemented. © 2012 Elsevier B.V. This work was supported by AGL2011-29857-C03-01 (Ministerio Ciencia e Innovación) and CSD2007-00063 FUN-CFOOD (Programa CONSOLIDER-INGENIO 2010) projects and one project of the Comunidad Autónoma de Madrid (S-0505/AGR/000153). C.T. acknowledges the Swedish Research Council FORMAS (229-2009-1527); the Swedish Research Council (VR, 2006-4084, 2010-333); and the Swedish Foundation for Strategic Research (SSF, RMA08-0044). M.C.-P. thanks the Spanish Ministry of Science and Innovation for her Juan de la Cierva contract (JCI-2009-05297). S0505/AGR-00153/ALIBIRD

Resumen del póster presentado a la VI Reunión de Expertos en Tecnologías de Fluidos Comprimidos celebrada en Madrid del 28 al 29 de junio de 2012., Nowadays, the concept of chemical preservatives in food is very controversial. Synthetic antioxidants such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are commonly used in the food industry due their effectiveness and low price. Nevertheless, the toxicity of these compounds drew attention to their side effects on the human body and possible carcinogenic properties. Modern consumer options have been redirected to natural alternatives, healthier and more diversified in terms of chemical composition and functional properties. Therefore, in the last years an increased interest to obtain natural bioactive compounds that can be used in the food industry has been observed. Besides, these components may be also useful for the development of functional foods that can provide additional physiological benefits, other than energy and nutrition. Pressurized liquid extraction (PLE) is applied for extraction of natural compounds from two raw materials from Romania: ramson (Allium ursinum), plums (Prunus domestica) and a raw material from Spain: lemon balm (Melissa officinalis). The antioxidant activities of the extracts were determined by using DPPH (1,1- diphenyl-2-picrylhydrazyl) radical scavenging and trolox equivalent antioxidant capacity (TEAC) in-vitro assays. The content of total phenolics in the extracts was determined spectrometrically according to the Folin-Ciocalteu procedure and calculated as gallic acid equivalents. The results support the possibility that these raw materials, which are commonly used in the Romanian and Spanish diet, can contribute to protective effects on human health. However, in vivo experiments and the absorption and metabolism of plants' bioactives are still necessary to further shed light on their efficacy in disease risk reduction., This work has benefited from financial support through the 2010 POSDRU/89/1.5/S/52432 project, Organizing the national interest postdoctoral school of applied biotechnologies with impact on Romanian bioeconomy, project co-financed by the European Social Fund through the Sectoral Operational Programme Human Resources Development 2007–2013.

2 páginas.-- Trabajo presentado al "Flucomp 2011: V Reunión de Expertos en Tecnologías de Fluidos Comprimidos" celebrada en Burgos (España) del 15 al 17 de junio de 2011.

CE with UV detection was used for the first time to determine the enantioselective adsorption of the short-chain tricarboxylic acid, 3-carboxy adipic acid, on minerals as a mean of investigating plausible mechanisms for the origin of biochemical homochirality on Earth. The use of vancomycine as chiral selector in the separation buffer using the partial filling technique enabled the separation of the two enantiomers of this organic acid in about 12 min. Taking into account that this compound has a low absorption of the UV light, and in order to achieve the sensitivity needed to determine the enantiomeric excess of samples of 3-carboxy adipic acid adsorbed on minerals, we applied a strategy consisting of a field-amplified sample stacking together with the use of a bubble capillary and detection at low wavelength (192 nm). This combination enabled an LOD of about 10-7 M and the determination of the enantiomeric excess of 3-carboxy adipic acid adsorbed on calcite and feldspar mineral samples at subnanomol levels of this acid. Results showed that an enantioselective adsorption of the enantiomers of 3-carboxy adipic acid on minerals took place. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.