79 research outputs found

    Physical Treatments and Propolis Extract to Enhance Quality Attributes of Fresh-Cut Mixed Vegetables

    Get PDF
    The impact of individual and combined application of propolis extract (PE) plus ultrasound (ULT) or thermal treatment (TT) on the microbiological, nutritional, physicochemical and sensory quality of fresh-cut mixed vegetables for soup (celery, leek and butternut squash) stored at 5C was studied. The use of PE slightly reduced microbial growth, inhibited the activity of browning related enzymes and improved quality attributes during refrigerated storage. Moreover, PE was effective to reduce ascorbic acid losses in the product maintaining its nutritional quality. TT greatly lowered the initial microbial load (1.7–2.2 log units) and also reduced microbial growth on mixed vegetables extending its microbiological shelf-life to 5 days. Furthermore, TT inactivated browning enzymes improving visual quality; however, ascorbic acid degradation adversely affected nutritional quality. Meanwhile, ULT caused a significant microbial inactivation, reduced browning enzyme activity and also the inhibitory effect on polyphenoloxidase enzyme was enhanced by combining ULT with PE. Practical Applications: The use of natural agents, as propolis extract, along with physical treatments to preserve the quality of fresh-cut mixed vegetables for soup might be an interesting option to address the concerns of the consumer about the use of synthetic chemical antimicrobials potentially harmful for health.Fil: Alvarez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; ArgentinaFil: Ponce, Alejandra Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; ArgentinaFil: Goyeneche, Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; ArgentinaFil: Moreira, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentin

    Green ultrasound-assisted processing for extending the shelf-life of prebiotic-rich strawberry juices

    Get PDF
    Adding value to conventional fruit juices by including prebiotic compounds into their formulation and preserving them using non-thermal, eco-friendly and safe technologies represents interesting and strategic approaches to diversify the healthy and innovative food products offer. In this context, the effect of ultrasound-assisted processing (for 15 and 30 min, 40 kHz, 180 W) on microbiological, physicochemical, nutritional and sensory quality of prebiotic-rich strawberry juices was investigated during storage (14 days, 5 ºC). Compared to untreated samples, the applied preservation treatments enhanced the microbiological and nutritional quality of samples by significantly reducing native microflora counts and increasing the total phenolic content (leading to a higher antioxidant capacity) of prebiotic-rich strawberry juices. Ultrasound processing and prebiotic enrichment had no negative effect on sensory attributes of enriched samples, suggesting that this non-thermal technique allowed to successfully retain the fresh-like attributes of strawberry juices during their shelf-life, contributing to the good sensory stability of juices. In addition, ultrasound treatments had no detrimental impact on physicochemical quality and ascorbic acid content of enriched samples, showing similar stability to control samples during storage. Based on our results, ultrasound processing appears to be a promising non-thermal technique to ensure a stable product from both microbiological and sensory points of view with improved antioxidant capacity and unaltered physicochemical quality while offering a healthier, nutritive and valuable food alternative.Fil: Cassani, Lucía Victoria. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tomadoni, Bárbara María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Moreira, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentin

    Impact of Production System on Quality Indices Distribution in Butterhead Lettuce: A Comparative Study among Open Field and Greenhouse

    Get PDF
    Butterhead lettuce quality was followed through changes in physical, physiological, microbiological, nutritional and sensory indices during postharvest storage. Production was in greenhouses, traditional and mulch, and in the field. Greenhouse lettuce heads had higher nutritional and sensory quality at harvest and lower enzymatic browning. Increased exposure to environmental conditions for open field grown lettuce heads may initiate defense mechanisms that could affect texture, color and appearance. During refrigerated postharvest storage, greenhouse lettuce heads had better leaf color and texture and were less susceptible to enzymatic browning. There was no difference in postharvest shelf life for greenhouse and field grown plants. Production in greenhouses produced important marketing benefit, along greater weight per plant and leaf number, by increasing producer profitabilityFil: Goñi, María Gabriela. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; ArgentinaFil: Moreira, Maria del Rosario. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Agüero, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; ArgentinaFil: Roura, Sara Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentin

    Optimization of ultrasound, vanillin and pomegranate extract treatment for shelf-stable unpasteurized strawberry juice

    Get PDF
    Optimum combination of ultrasound, vanillin and pomegranate extract to improve quality of strawberry juice was determined using response surface methodology. Samples were stored at 5 °C for 14 days. The optimal conditions to simultaneously minimize native microflora, maximize nutritional parameters and minimize the impact on sensory quality resulted in: 7.5 min of ultrasound treatment, pomegranate extract concentration of 360 μg/mL and vanillin concentration of 0.925 mg/mL. A new batch of strawberry juice was treated at these optimal conditions and stored for validation of the optimization and to evaluate the performance of the optimum treatment on quality parameters throughout storage. Furthermore, a second batch of juice was inoculated with Escherichia coli O157:H7 and processed at optimal conditions to evaluate the effectiveness of the treatment on the pathogen survival. The native microflora of the juice, as well as inoculated pathogen, decreased significantly using the proposed hurdle technologies, with no impact on sensory parameters. Ascorbic acid retention was slightly decreased by the optimum treatment; however, DPPH and polyphenolic compounds were significantly higher than those in untreated sample. Overall, a combination of ultrasound, vanillin and pomegranate extract showed interesting potential to enhance quality and safety of strawberry juice, extending the shelf-life of the product.Fil: Tomadoni, Bárbara María. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Cs.agrarias. Area Ciencia de Alimentos; ArgentinaFil: Cassani, Lucía Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Cientifíca y Tecnológica; ArgentinaFil: Ponce, Alejandra Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Cs.agrarias. Area Ciencia de Alimentos; ArgentinaFil: Moreira, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Cs.agrarias. Area Ciencia de Alimentos; ArgentinaFil: Agüero, M. V.. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Oregano essential oil-pectin edible films as anti-quorum sensing and food antimicrobial agents

    Get PDF
    Edible films can be used as carriers for antimicrobial compounds to assure food safety andquality; in addition, pathogenesis of food bacteria is related to a cell to cell communicationmechanism calledquorum sensing(QS). Oregano essential oil (OEO) has proved to beuseful as food antimicrobial; however, its foodapplications can be compromised by thevolatile character of its active constituents.Therefore, formulation of edible films containingOEO can be an alternative to improve its food usages. QS inhibitory activity of OEO andpectin-OEO films was evaluated usingChromobacterium violaceumas bacterial model.Additionally, antibacterial activity was tested againstEscherichia coliO157:H7,SalmonellaCholeraesuis,Staphylococcus aureus,andListeria monocytogenes. OEO was effective toinhibit bacterial growth at MIC of 0.24 mg/mL for all tested bacteria and MBC of 0.24,0.24, 0.48, and 0.24 mg/mL againstE. coliO157:H7,S.Choleraesuis,S. aureus, andL.monocytogenes, respectively. Pectin-films incorporated with 36.1 and 25.9 mg/mL of OEOshowed inhibition diameters of 16.3 and 15.2 mm forE. coliO157:H7; 18.1 and 24.2 mm forS.Choleraesuis; 20.8 and 20.3 mm forS. aureus; 21.3 and 19.3 mm forL. monocytogenes,respectively. Pectin-OEO film (15.7 mg/mL) was effective againstE. coliO157:H7 (9.3 mm),S. aureus(9.7 mm), andL. monocytogenes(9.2 mm), but not forS.Choleraesuis. Allconcentrations of OEO (0.0156, 0.0312, 0.0625 and 0.125 mg/mL) and pectin-OEO films(15.7, 25.9 and 36.1 mg/mL) showed a significant anti-QS activity expressed as inhibition ofviolacein production byC. violaceum. Additionally, the application of pectin-OEO films waseffective reducing total coliforms, yeast, and molds of shrimp and cucumber slices storedat 4◦C during 15 d.These results demonstrated the potential of pectin films enriched withOEO as food related microorganisms and QS inhibitorsFil: Alvarez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería En Alimentos; ArgentinaFil: Ortega Ramirez, Luis Alberto. Centro de Investigación en Alimentación y Desarrollo. Hermosillo; MéxicoFil: Gutierrez Pacheco, Maria Melissa. Centro de Investigación en Alimentación y Desarrollo. Hermosillo; MéxicoFil: Bernal Mercado, Thalia. Centro de Investigación en Alimentación y Desarrollo. Hermosillo; MéxicoFil: Rodriguez Garcia, Isela. Centro de Investigación en Alimentación y Desarrollo. Hermosillo; MéxicoFil: Ponce, Alejandra Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería En Alimentos; ArgentinaFil: Moreira, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería En Alimentos; ArgentinaFil: Roura, Sara Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería En Alimentos; ArgentinaFil: Ayala Zavala, Jesús Fernando. Centro de Investigación en Alimentación y Desarrollo. Hermosillo; Méxic

    Gestión de recursos electrónicos en el Consorcio de Bibliotecas Universitarias Andaluzas. Una experiencia de cooperación bibliotecaria en entornos digitales

    Get PDF
    En la actualidad es difícil encontrar bibliotecas digitales nacidas bajo este concepto. La denominación representa más bien la evolución de las bibliotecas tradicionales, sobre todo universitarias, hacia un entorno en que la proliferación de recursos electrónicos en lo últimos años ha cambiado no sólo el concepto de biblioteca sino el mismo concepto de investigación, de estudio y por tanto de trabajo. Bajo esta premisa, en que señalamos recursos electrónicos como origen de bibliotecas digitales, son los consorcios bibliotecarios los que han contribuido de forma extraordinaria y definitiva a su desarrollo. La vieja idea de cooperación se ha materializado en ellos no sólo en la disposición de recursos propios sino que ha encontrado su máxima expresión en el entorno consorciado en que la adquisición y gestión compartidas han sido necesarias para dar respuesta a las necesidades que impone la proliferación de recursos electrónicos en las nuevas bibliotecas digitales. Claro ejemplo de esta afirmación, de estas nuevas formas de organización lo constituye el recientemente creado Grupo de Trabajo de Recursos Electrónicos del Consorcio de Bibliotecas Universitarias Andaluzas (CBUA), cuyo proyecto de cooperación y gestión contribuye a facilitar el acceso a la colección digital en el ámbito universitario andaluz. Se presenta el trabajo realizado hasta la fecha por el Grupo, así como las perspectivas de futuro. Se exponen la metodología de trabajo empleada, las líneas de actuación, las acciones realizadas, las herramientas utilizadas para optimizar la calidad en el acceso y difusión de los recursos de los que disponemos. Palabras clave: bibliotecas universitarias, bibliotecas digitales, gestión de recursos electrónicos, consorcios de bibliotecas, cooperación bibliotecaria

    Providing an in vitro depiction of microglial cells challenged with immunostimulatory extracellular vesicles of Naegleria fowleri

    Get PDF
    Naegleria fowleri is the causative agent of primary amoebic meningoencephalitis, a rapid and acute infection of the central nervous system with a fatal outcome in >97% of cases. Due to the infrequent report of cases and diagnostic gaps that hinder the possibility of recovering clinic isolates, studies related to pathogenesis of the disease are scarce. However, the secretion of cytolytic molecules has been proposed as a factor involved in the progression of the infection. Several of these molecules could be included in extracellular vesicles (EVs), making them potential virulence factors and even modulators of the immune response in this infection. In this work, we evaluated the immunomodulatory effect of EVs secreted by two clinic isolates of Naegleria fowleri using in vitro models. For this purpose, characterization analyses between EVs produced by both isolates were first performed, for subsequent gene transcription analyses post incubation of these vesicles with primary cultures from mouse cell microglia and BV-2 cells. Analyses of morphological changes induced in primary culture microglia cells by the vesicles were also included, as well as the determination of the presence of nucleic acids of N. fowleri in the EV fractions. Results revealed increased expression of NOS, proinflammatory cytokines IL-6, TNF-α, and IL-23, and the regulatory cytokine IL-10 in primary cultures of microglia, as well as increased expression of NOS and IL-13 in BV-2 cells. Morphologic changes from homeostatic microglia, with small cellular body and long processes to a more amoeboid morphology were also observed after the incubation of these cells with EVs. Regarding the presence of nucleic acids, specific Naegleria fowleri DNA that could be amplified using both conventional and qPCR was confirmed in the EV fractions. Altogether, these results confirm the immunomodulatory effects of EVs of Naegleria fowleri over microglial cells and suggest a potential role of these vesicles as biomarkers of primary acute meningoencephalitis.Projects C-2600: “Secreción de vesículas extracelulares por Naegleria fowleri y evaluación de su potencial rol inmunomodulador en un modelo in vitro” and C-1061: “Caracterización de antígenos de excreción/secreción y antígenos somáticos en amebas de vida libre mediante el empleo de anticuerpos policlonales producidos en roedores”, supported by Vicerrectoría de Investigación of the University of Costa RicaOficina de Asuntos Internacionales y Cooperación Externa (OAICE) of Universidad de Costa RicaFundación Carolina (Spain)“Contrato de Formación de Profesorado Universitario” of the Ministry of Science, Culture and Sports (Spain

    Validation Study Of Genetic Biomarkers Of Response To Tnf Inhibitors In Rheumatoid Arthritis

    Get PDF
    Genetic biomarkers are sought to personalize treatment of patients with rheumatoid arthritis (RA), given their variable response to TNF inhibitors (TNFi). However, no genetic biomaker is yet sufficiently validated. Here, we report a validation study of 18 previously reported genetic biomarkers, including 11 from GWAS of response to TNFi. The validation was attempted in 581 patients with RA that had not been treated with biologic antirheumatic drugs previously. Their response to TNFi was evaluated at 3, 6 and 12 months in two ways: change in the DAS28 measure of disease activity, and according to the EULAR criteria for response to antirheumatic drugs. Association of these parameters with the genotypes, obtained by PCR amplification followed by single-base extension, was tested with regression analysis. These analyses were adjusted for baseline DAS28, sex, and the specific TNFi. However, none of the proposed biomarkers was validated, as none showed association with response to TNFi in our study, even at the time of assessment and with the outcome that showed the most significant result in previous studies. These negative results are notable because this was the first independent validation study for 12 of the biomarkers, and because they indicate that prudence is needed in the interpretation of the proposed biomarkers of response to TNFi even when they are supported by very low p values. The results also emphasize the requirement of independent replication for validation, and the need to search protocols that could increase reproducibility of the biomarkers of response to TNFi
    corecore