97 research outputs found

    Utilización de aceites esenciales de variedades de orégano como conservante antimicrobiano, antioxidante y de las propiedades sensoriales de alimentos: quesos cottage, ricota y aceite de oliva

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    Tesis (Doctora en Ciencias Agropecuarias)--UNC- Facultad de Ciencias Agropecuarias, 2013.En nuestro país se producen cuatro variedades de oréganos: Mendocino, Compacto, Cordobés y Criollo. Esta planta aromática además de ser consumida cotidianamente como aromatizante de comidas puede ser destinada a la producción de aceites esenciales. El uso de aceites esenciales como conservantes naturales cobra especial importancia en la industria alimenticia, ya que estos compuestos son reconocidos como seguros (GRAS) para ser usados en forma intencionada en alimentos. Los aceites esenciales de orégano constituyen una alternativa como potenciales agentes antioxidantes y antimicrobianos prolongando la vida útil de los alimentos, especialmente aquellos ricos en grasas insaturadas, como es el caso del aceite de oliva, y aquellos que tienen alta actividad agua y que son susceptibles al deterioro microbiano, como es el caso de los quesos de pasta blanda como la ricota y el Cottage. El objetivo de este trabajo de tesis fue evaluar in-vitro las propiedades antioxidantes y antimicrobianas de aceites esenciales de las variedades de orégano producidas en Córdoba, Argentina, y evaluar el efecto conservante de dichos aceites esenciales sobre alimentos con alto contenido graso como el aceite de oliva y de humedad como los quesos de pasta blanda (ricota y Cottage) para preservar la calidad química, sensorial, nutricional y microbiológica de dichos productos. Para responder a estos objetivos se realizaron a) la determinación de la composición físico-química de los aceites esenciales de orégano (AE) de las variedades Mendocino (Men), Compacto (Com), Cordobés (Cor) y Criollo (Crio), b) la actividad antioxidante de los aceites esenciales mediante los test DPPH, FRAP; ABTS; ORAC y carotenos/linoleico, c) la actividad biocida de los aceites esenciales contra bacterias gram positivas y negativas, levaduras, hongos filamentosos y nemátodos; d) análisis sensoriales sobre productos alimenticios como queso ricota y aceite de oliva adicionados con aceites esenciales de orégano midiendo la aceptabilidad por parte de los consumidores y e) estudios de almacenaje para evaluar cambios químicos, sensoriales y microbiológicos que se producen en quesos de pasta blanda (ricota y Cottage) y aceite de oliva preparados con el agregado de aceites esenciales de orégano. Los diferentes AE de orégano presentaron distinta composición química, actividad antioxidante y biocida. El AE Crio presentó mayor actividad antioxidante para los métodos ABTS (TEAC de 0,21 Mm Tr/mg AE), FRAP (0,18 mM Ac Asc/mg AE) y ORAC (TE de 1,38 mM Tr/mg AE) y fue el que presentó el mejor comportamiento antimicrobiano con respecto a los demás AE exhibiendo bajos valores de CIM y con capacidad bactericida (CBM) contra E. coli y B. cereus al igual que AE Cor. El AE Men fue el más aceptado sensorialmente en las pruebas de aceptabilidad por parte de los consumidores cuando se los incluyó en los alimentos. Los AE tuvieron mayor actividad biológica pero presentaron menor aceptabilidad al ser incluidos en los alimentos. El aceite de oliva saborizado con AE Cor almacenado en Oscuridad presento mayor estabilidad y preservó con niveles mayores de intensidad los atributos sensoriales positivos del producto. En las muestras de queso Cottage el AE Cor mostró al final del almacenaje menores contenidos de ácidos láctico, acético y cítrico, y menor número de microorganismos mesófilos totales que el resto de los tratamientos. También estas muestras presentaron mejor relación de ácidos grasos saturados/insaturados al final del almacenaje resultados que indican que el AE Cor tiene una muy buena actividad antioxidante y antimicrobiana cuando es aplicada sobre alimentos. En general los AE de especies de orégano presentaron buena aptitud para la conservación de alimentos impidiendo el deterioro oxidativo en aceite de oliva y en quesos (ricota y Cottage), además de mostrar buena actividad antimicrobiana en productos con alta actividad agua como el queso Cottage.Four different oregano varieties Mendocino, Compacto, Cordobés, and Criollo are farmed In Córdoba province. This aromatic herb besides are consumed daily as food seasoning but also, could be used for the production of essential oils. The use of essential oils as natural preservative agents is particularly important in the food industry, since these compounds are recognized as safe (GRAS). Essential oils of oregano are an alternative as potential antioxidant and antimicrobial agents for prolonging the shelf life of products, especially in food with high unsaturated fats, such as olive oil, and in foods with high water activity that are susceptible to microbial spoilage, such as cottage cheese and ricotta. The aim of this thesis study was to evaluate antioxidant and antimicrobial properties in vitro of essential oils of oregano varieties produced in Cordoba, Argentina, and to assess the preserving effect of these essential oils on high-fat foods as oil olive and on high humidity food as ricotta and cottage cheese to preserve the chemical, sensory, nutritional, and microbiological quality of these products. To reach these objectives several activities were performed: a) determination of physical and chemical composition of oregano essential oils (EO) of the varieties Mendocino (Men), Compacto (Com), Cordobés (Cor), and Criollo (Crio), b) antioxidant activity of essential oils by the DPPH, FRAP, ABTS; ORAC and carotenes / Linoleic tests, c) biocide activity of oregano essential oils against gram positive and negative bacteria, yeast, filamentous fungi and nematodes, d) sensory analyzes on cheese/ricotta and olive oil added with essential oils to determine acceptability for consumers e) storage studies to evaluate chemical, sensory, and microbiological changes produced in soft cheeses (ricotta and Cottage) and olive oil prepared with the addition of oregano essential oils. EO of oregano varieties showed differences in chemical composition, antioxidant and biocide activities. Crio EO had higher antioxidant activity in ABTS (TEAC: 0.21 Mm Tr/mg EO), FRAP (0.18 mM Asc Ac/mg EO), and ORAC methods (TE: 1.38 mM Tr/mg EO) and exhibited the highest antimicrobial performance presenting lower MIC values and bactericidal capacity (MBC) against E. coli and B. cereus, followed by Cor EO. Men EO had the greatest sensory acceptability for the consumers when this EO was included in food product. The EO were more active biologically but had lower acceptance when they were included in food. Olive oil flavored with Cor EO stored in darkness showed higher storage stability and preserved with higher ratings the positive sensory attributes in olive oil. Cottage cheese sample with Cor EO presented at the end of the storage lower lactic, acetic, and citric acid contents, and fewer total mesophilic microorganisms than other treatments. These Cottage cheese samples also presented better saturated/unsaturated fatty acids ratio at the end of storage which indicates that the Cor EO has a very good antioxidant and antimicrobial activity when is added to a food product. In general, oregano EO showed good aptitude for food preservation by preventing oxidative deterioration in olive oil and cheeses (ricotta and Cottage), and showed good antimicrobial activity in high water activity products like cheese Cottage

    The Coastal Scenery of São Miguel Island, Azores Archipelago: Implications for Coastal Management

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    In this study, coastal scenic beauty was assessed at 29 sites at São Miguel, which is one of the Azores Islands, i.e., a group of remote volcanic islands in the North Atlantic Ocean. The assessment was based on in situ observations and the use of the Coastal Scenic Evaluation System (CSES), which consists of a checklist with 26 physical- and anthropic-weighted parameters and the Fuzzy Logic Approach (FLA) mathematical tool. The study sites were classified into five classes according to their typology and their scenic value, ranging from Class I (natural sites of great scenic beauty) to Class V (unattractive, urbanized sites). Concerning beach typology, 13% were remote, 28% rural, 28% village, and 31% urban. Concerning scenic beauty, 10% of the sites belonged to Class I, 14% to Class II, 17% to Class III, 31% to Class IV, and 28% to Class V. The physical parameters were linked to the characteristics of the geological volcanic landscapes, and the anthropic parameters essentially reflected the presence of tourism and public services. The results of the assessment provide a scientific basis for developing a management strategy for the preservation and conservation of the coastal areas and their sustainable development.This work was supported by the Paleoenvironmental Changes research group (vigrob-167) of the University of Alicante and the PAI Research Group RNM-373 of Andalusia (Spain)

    Rheological behavior, antimicrobial and quorum sensig inhibition study of an argentinean oregano essential oil nanoemulsion

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    In this study, Argentinean oregano essential oil (OEO) nanoemulsions (NEs) were developed. Four NEs were prepared: a control (CNE), EONE1 (10.6 mg EO/g NE), EONE2 (106 mg EO/ g NE), and EONE3 (160 mg EO/g NE) and tested for antimicrobial activity against Staphylococcus aureus ATCC 13565, Listeria monocytogenes Scott A, Pseudomonas aeruginosa ATCC 14213, and Escherichia coli O157:H7 using a broth microdilution assay and quorum sensing inhibition in a model using Chromobacterium violaceum ATCC 12472, where the production of violacein was quantified. The chemical composition of the EO was determined by gas chromatography–mass spectrometry. The average particle size (nm) and polydispersity index were monitored over 14 days at two different storage temperatures (4 and 23°C). A rheological behavior study was carried out using a dynamic shear rheometer, and flow curves, as well as viscoelastic properties, were determined. E. coli and L. monocytogenes were the most sensitive microorganisms to EONE (MIC of 2 and 5 mg/ml for EOEN3). Sub-MICs for NE were found at lower concentrations than those for pure EO. A significant reduction in violet pigment intensity and colorless coloration (p G″) was observed in the high-frequency region, presenting a viscoelastic behavior, appearing as a wormlike micellar solution. For EONE3, a strong increase in both moduli was observed with increasing OEO concentration. The G′ was about one order of magnitude higher than the G″ over the whole frequency range, indicating the presence of a gel-like structure. The incorporation of EOs into an NE increased their stability, lowering the particle size, leading to a wormlike micelle with higher viscosity. Moreover, this NE had good antimicrobial activity and novel quorum-sensing inhibition activity. The results of this study indicated that Argentinean OEO NE could be used in a food system as a natural and stable antimicrobial agent.Fil: Asensio, Claudia Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Quiroga, Patricia Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Al-Gburi, Ammar. School Of Environmental And Biological Sciences; Estados UnidosFil: Huang, Quingron. School Of Environmental And Biological Sciences; Estados UnidosFil: Grosso, Nelson Rubén. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    Restos de pingüinos del cenozoico medio de la Cordillera Patagónica

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    Middle Cenozoic marine fossil-bearing beds crop out in the Cerro Plataforma (western Chubut Province, Argentina) at about 1,400 m a.s.l. They are located 500 km far from the modern Atlantic coast and only 50 km from the Pacific Ocean. Well preserved penguin bones and a shark tooth were found therein. Invertebrates include corals, bryozoans, abundant mollusks, echinoids, and crabs. Morphogeometric analysis and comparative description confirmed that the penguin humerus is referable to Palaeospheniscus bergi Moreno and Mercerat, 1891. Most of the fossils indicate a Miocene age. However, there is a debate about if the bearing beds are of Pacific or Atlantic origin. Fossil invertebrates identifiable at species level reveal Pacific affinity, the shark species is cosmopolitan, and Palaeospheniscus bergi is known from early Miocene Atlantic units of southern South America. Yet, Palaeospheniscus Moreno and Mercerat, 1891 is also known from Miocene Pacific beds but it has not been identified at specific level yet. This is the highest site in topographic terms in which penguin fossils occur. This indicates a remarkable uplift for the area, probably from the middle Miocene.Capas portadoras de fósiles marinos del Cenozoico medio afloran en cerro Plataforma (oeste de la Provincia del Chubut, Argentina) a unos 1.400 m s.n.m. Están localizadas a 500 km de la costa pacífica actual y a solo 50 km de la pacífica. Fueron hallados restos de pingüinos y un diente de tiburón bien preservados. Entre los fósiles de invertebrados se incluyen corales, briozoos, abundantes moluscos, equinoideos y cangrejos. Los análisis morfogeométricos y la descripción comparada confirmaron la asignación del húmero de pingüino a Palaeospheniscus bergi Moreno y Mercerat, 1891. La mayoría de los fósiles indican una edad Miocena. Sin embargo, existe un debate sobre si estas capas poseen un origen pacífico o atlántico. Los fósiles de invertebrados identificables a nivel de especie presentan afinidades pacíficas, la especie de tiburón es cosmopolita, y Palaeospheniscus bergi es conocido en unidades atlánticas del Mioceno temprano de América del Sur. A pesar de esto, el género Palaeospheniscus Moreno y Mercerat, 1891 es también conocido en capas miocenas del Pacífico, aunque la especie no ha sido aún identificada. En términos topográficos, este es el sitio más elevado en el que se han hallado restos de pingüinos. Esto indica un notable levantamiento del área, probablemente durante el Mioceno medio.Fil: Acosta Hospitaleche, Carolina Ileana Alicia. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Griffin, Miguel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Asensio, Marcos. TECPETROL; ArgentinaFil: Cione, Alberto Luis. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tambussi, Claudia Patricia. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Centrosome reduction in newly-generated tetraploid cancer cells obtained by separase depletion

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    Altres ajuts: Fundación Científica de la Asociación Española Contra el Cáncer (GCB13131592CAST)Tetraploidy, a common feature in cancer, results in the presence of extra centrosomes, which has been associated with chromosome instability (CIN) and aneuploidy. Deregulation in the number of centrosomes triggers tumorigenesis. However, how supernumerary centrosomes evolve during the emergence of tetraploid cells remains yet to be elucidated. Here, generating tetraploid isogenic clones in colorectal cancer and in non-transformed cells, we show that near-tetraploid clones exhibit a significant increase in the number of centrosomes. Moreover, we find that centrosome area in near-tetraploids is twice as large as in near-diploids. To evaluate whether centrosome clustering was occurring, we next analysed the number of centrioles revealing centriole amplification. Notwithstanding, more than half of the near-tetraploids maintained in culture do not present centrosome aberrations. To test whether cells progressively lost centrioles after becoming near-tetraploid, we transiently transfected diploid cells with siRNA against ESPL1 /Separase, a protease responsible for triggering anaphase, to generate newly near-tetraploid cells. Finally, using this model, we assessed the number of centrioles at different time-points after tetraploidization finding that near-tetraploids rapidly lose centrosomes over time. Taken together, these data demonstrate that although most cells reduce supernumerary centrosomes after tetraploidization, a small fraction retains extra centrioles, potentially resulting in CIN

    Restos de pingüinos del Cenozoico medio de la cordillera patagónica

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    Middle Cenozoic marine fossil-bearing beds crop out in the Cerro Plataforma (western Chubut Province, Argentina) at about 1,400 m a.s.l. They are located 500 km far from the modern Atlantic coast and only 50 km from the Pacific Ocean. Well preserved penguin bones and a shark tooth were found therein. Invertebrates include corals, bryozoans, abundant mollusks, echinoids, and crabs. Morphogeometric analysis and comparative description confirmed that the penguin humerus is referable to Palaeospheniscus bergi Moreno and Mercerat, 1891. Most of the fossils indicate a Miocene age. However, there is a debate about if the bearing beds are of Pacific or Atlantic origin. Fossil invertebrates identifiable at species level reveal Pacific affinity, the shark species is cosmopolitan, and Palaeospheniscus bergi is known from early Miocene Atlantic units of southern South America. Yet, Palaeospheniscus Moreno and Mercerat, 1891 is also known from Miocene Pacific beds but it has not been identified at specific level yet. This is the highest site in topographic terms in which penguin fossils occur. This indicates a remarkable uplift for the area, probably from the middle Miocene.Facultad de Ciencias Naturales y Muse

    Impact on prostate cancer clinical presentation after non-screening policies at a tertiary-care medical center- a retrospective study

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    Background: In May 2012 the US Preventive Task Force issued a 'D' recommendation against routine PSA-based early detection of prostate cancer. This recommendation was implemented progressively in our health system. The aim of this study is to defne its impact on prostate cancer staging at a tertiary care institution. Methods: A retrospective analysis was performed from 2012 until 2015 at a single center. We analyzed the total number of biopsies performed per year and the positive biopsy rate. For those patients with positive biopsies we recorded diagnostic PSA, clinical stage, ISUP grade group, nodal involvement and metastatic status at diagnosis. Results: A total of 1686 biopsies were analyzed. The positive biopsy rate increased from 25% in 2012 to 40% in 2015 (p<0.05). No change in median PSA was noticed (p=0.627). The biopsies detected higher ISUP grades (p=0.000). In addition, newly diagnosed prostate cancer presented a higher clinical stage (p=0.005), higher metastatic rates (p=0.03) and a tendency to higher lymph node involvement although not statistically signifcant (p=0.09). Conclusion: After the 2012 recommendation, patients presented a higher probability of a prostate cancer diagnosis, with a more adverse ISUP group, clinical stage and metastatic disease. These results should be taken into consideration to implement a risk adapted strategy for prostate cancer screening. Keywords: Prostate cancer, Prostate specifc antigen, Prostate cancer screenin

    Estrategia conjunta de protección del patrimonio de palmeras en el municipio de Palma sobre la experiencia piloto público-privada

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    [ES] La estrategia surge como necesidad ante la rigidez de las Administraciones, (compartimentadas en áreas por ámbitos competenciales), especialmente en la tutela del cumplimiento de la Ley de Sanidad Vegetal en el ámbito privado, en lo relativo a plagas que afectan a jardines particulares. Todo ello supone un vacío y un problema real en la lucha contra las plagas en este y otros Ayuntamientos. El seguimiento de la plaga desde el conocimiento de la ubicación (georeferencia,) de sus posibles hospedantes, y la evolución del nivel de afección, así como el establecimiento de protocolos conjuntos nos ha permitido conseguir buenos resultados sobre el ámbito trabajado mediante esta estrategia. La convivencia de espacios público-privado en el municipio, con una elevada prevalencia de lo privado sobre lo público, de manera acusada en algunas barriadas, ha motivado que el Servicio de Parques y Jardines de este Ayuntamiento se plantee una estrategia de erradicación conjunta que integra la tutela y el seguimiento de particulares, en la estrategia de lucha contra las plagas en las palmeras de nuestro municipio, valoradas sólo en lo público en más de 6,5 millones de eurosMartínez Asensio, O.; Gascón López, I.; Hernández Cabrera, C. (2014). Estrategia conjunta de protección del patrimonio de palmeras en el municipio de Palma sobre la experiencia piloto público-privada. En XVI CONGRESO NACIONAL DE ARBORICULTURA. Editorial Universitat Politècnica de València. 31-43. http://hdl.handle.net/10251/85879OCS314

    Chemical composition and antioxidant activity of phenolic extracts from peanut skins obtained by different industrial process

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    Peanut skins present phenolic compounds with antioxidant properties which are excellent as a source of natural antioxidants. In food products, the antioxidants have the function ofneutralizedthe action of free radicals produced by oxidation reactions. The objective of this study was to determine the chemical composition and antioxidant activity of extracts rich in phenolic compounds form peanut skins obtained by two industrial process.Fil: Larrauri, Mariana. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Larrauri, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Asensio, Claudia M. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Asensio, Claudia M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Martín, María Paula. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Martín, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Zunino, M. Paula. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: Zunino, M. Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Zygadlo, Julio A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: Zygadlo, Julio A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Grosso, Nelson R. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Grosso, Nelson R. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Fil: Nepote, Valeria. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: Nepote, Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; Argentina.Otras Ciencias Agrícola
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