Oenococcus oeni allows the increase of antihypertensive and antioxidant activities in apple cider

This study aimed to investigate the impact of the malolactic fermentation (MLF) carried out by Oenococcus oeni on antihypertensive and antioxidant activities in cider. The MLF was induced using three strains of O. oeni. The modification in phenolic compounds (PCs) and nitrogen organic compounds, antioxidant, and antihypertensive activities were determined after MLF. Among the 17 PCs analyzed caffeic acid was the most abundant compound and phloretin, (−)-epicatechin, and myricetin were detected only in malolactic ciders, however, (−)-epigallocatechin was not detected after MLF. The evaluation of nitrogen organic compounds revealed a drop in total protein concentration (from 17.58 to 14.00 mg N/L) concomitantly with a significant release of peptide nitrogen (from 0.31 to a maximum value of 0.80 mg N/L) after MLF. In addition, an extracellular proteolytic activity was evidenced in all MLF supernatants. The FRAP activity increased reaching a maximum of 120.9 μmol FeSO4/mL and the ABTS radical-scavenging activity increased until 6.8 mmol ascorbic acid/L. Moreover, the angiotensin I-converting enzyme inhibitory activity reached a maximum value of 39.8%. The MLF conducted by O. oeni in ciders enables the increase of interesting biological activities and this finding could constitute a valuable tool to add value to final product.Fil: Kristof, Irina. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Ledesma, Silvana Cecilia. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Apud, Gisselle Raquel. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Vera, Nancy Roxana. Universidad Nacional de Tucumán; ArgentinaFil: Aredes Fernández, Pedro Adrián. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentin

Escuela secundaria posible

REPENSAR LA EDUCACIÓN SECUNDARIA Colección de infografías II Parte Seguimiento de medios de comunicación 2017-2019Fil: Ferreyra, Horacio Ademar. Universidad Católica de Córdoba. Facultad de Educación; ArgentinaFil: Di Francesco, Adriana Carlota. Universidad Católica de Córdoba. Facultad de Educación; ArgentinaFil: Equipo de investigación en educación de adolescentes y jóvenes. Unidad Asociada CONICET. Universidad Católica de Córdoba. Facultad de Educación; Argentina

Estudios de prospectiva en educación. Currículum, saberes y prácticas ¿Hacia dónde y cómo puede evolucionar el tema en los próximos 10 años?

Fil: Ferreyra, Horacio Ademar. Universidad Católica de Córdoba. Facultad de Educación; ArgentinaFil: Di Francesco, Adriana Carlota. Universidad Católica de Córdoba. Facultad de Educación; ArgentinaFil: Tenutto, Marta Alicia. Universidad Católica de Córdoba. Facultad de Educación; Argentin

Novel and rapid methods for histamine quantification in wine and culture medium

Fermented beverages are frequently contaminated with histamine, produced by lactic acid bacteria exhibiting histidine decarboxylase activity. In wine, presence of histamine is associated with a lack of hygiene during the winemaking process. Determination of histamine is of great importance because it can be toxic to humans. Therefore, two rapid, inexpensive and simple methods were developed to determine histamine in wine and culture medium and the samples did not require complicated extraction procedures. The new colorimetric method showed a good correlation between absorbance and histamine concentration in the interval of 1.0 ? 100 mg/L of histamine in wine and Moeller culture broth samples (R2 = 0.9981 and 0.9941, respectively). Thin layer chromatography (nTLC) with a new visualization reagent also demonstrated a good correlation between histamine concentrations between 5.0 and 100 mg/L and absorbance with an R2 of 0.9882 and 0.9839 for wine and Moeller culture broth samples, respectively. Both methods showed a high correlation with ELISA (R2 = 0.9972 and 0.9968, respectively) and also exhibited good histamine recovery (higher than 87%). The detection limit of the two new methods was comparable with existing analytical methods. Both methods seem to be suitable for routine analysis to monitor histamine in any research and wine quality control laboratory.Fil: Ledesma, Silvana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología. Cátedra de Tecnología de Enzimas; ArgentinaFil: Rubio, María Cristina. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología. Cátedra de Tecnología de Enzimas; ArgentinaFil: Aredes Fernández, Pedro Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología. Cátedra de Tecnología de Enzimas; Argentin

Identification of histidine and tyrosine decarboxylating bacteria from Tucumán red wine

Different species of lactic acid bacteria (LAB) produce biogenic amines (BA) in wine, including histamine and tyramine. Thereby, it was determined through sequencing of the 16S rDNA gene that 11 LAB isolates from Tucumán red wine correspond to Lacticaseibacillus paracasei species, and through RAPD-PCR were grouped into 4 clusters. The presence of hdc and tdc genes was also demonstrated. L. paracasei AT45 was the main producer strain of BA in a culture medium, at a concentration of 103 cfu mL−1 producing 6.52 mg L−1 of histamine and 3.57 mg L−1 of tyramine. The production of histamine and tyramine in wine was evidenced. The inoculation of the Oenococcus oeni strain, as a strategy to reduce the formation of BA in wine, was evaluated. In the wine inoculated with both microorganisms at a concentration of 107 cfu mL−1, a decrease of BA production for the pure culture of L. paracasei AT45 was demonstrated. In wine inoculated with O. oeni in the presence of L. paracasei AT45 at 103 cfu mL−1, BA was not detected. This study evidenced the first histamine and tyramine-producing L. paracasei strain identified from Argentinian wine. Furthermore, the results represent an advance in the pursuit of the reduction of biogenic amine formation.Fil: Ledesma, Silvana Cecilia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Rubio, María Cristina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Aredes Fernández, Pedro Adrián. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentin

New Rapid, Simple, and Cheap Methods to Determine Tyramine in Fermented Beverages and Culture Medium

Fermented beverages are frequently contaminated with biogenic amines, produced by lactic acid bacteria that exhibit decarboxylase activity. Wine spoilage can occur when increased tyramine concentrations creates a product harmful to consumers. Determination of tyramine is important because it elevates blood pressure, which might cause a migraine attack in susceptible persons. We developed two rapid, inexpensive, and simple methods, a colorimetric technique and a thin-layer chromatography technique, to determine tyramine concentrations in culture medium and wine without complicated extraction procedures. The new colorimetric method showed high correlation between absorbance and tyramine concentrations from 1.0 to 100 mg/L in Moeller culture broth and red wine (r2 = 0.9995 and 0.9988, respectively). Thin-layer chromatography (nTLC) with a new visualization reagent also dem-onstrated a high correlation among tyramine concentrations between 5.0 and 100 mg/L and absorbance, with an r2 of 0.988. Both new methods showed a high correlation with high-performance liquid chromatography (colorimetric method, r2 = 0.9995; nTLC, r2 = 0.9982) and exhibited good tyramine recovery (>83%). The detection limit of the two new methods was comparable with existing analytical methods. The new assays are simple, inexpensive, and do not require any laborious pre-treatment of the samples. Both methods are suitable for routine analysis to quickly and safely monitor tyramine in a research or wine quality control laboratory. The methods were validated in various matrices: in culture media frequently used in microbiology laboratories, in common Argentine wine varietals, such as Cabernet Sauvignon and Torrontés, and in other fermented beverages, such as sparkling wine, cider, and craft beer.Fil: Ledesma, Silvana Cecilia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Rubio, María Cristina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Aredes Fernández, Pedro Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

Influence of wine phenolic compounds on viability and exopolysaccharide production by Pediococcus pentosaceus

Low molecular weight phenolic fractions of Cabernet Sauvignon (LMF-C) and Malbec (LMF-M) wines from Colalao del Valle, Tucuman, Argentina, were isolated and chemically characterized. The effect of these phenolic fractions on viability and exopolysaccharide production of Pediococcus pentosaceus E2p, a wine spoilage bacterium, was examined in synthetic wine-like medium (SWM). The concentration of phenolic acids detected in LMF-C was 47.28% higher than that determined in LMF-M. The presence of LMF-C and LMF-M at concentration four times higher than detected in wine, produce a decrease in viable cells from the inoculum of 3.01 and 3.65 Log cfu mL-1, respectively and sometimes a significantly decrease in exopolysaccharide release was detected for both fractions. Considering the current trend in the search of potential and effective antimicrobial agents for total or partial replacement of sulfites in the winemaking process, these results could be of great interest, even thought that phenolic compounds can also add extra value to the final product, considering their recognized beneficial properties on human health.Fil: Stivala, Maria Gilda. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Ledesma, Silvana Cecilia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Rubio, María Cristina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología; ArgentinaFil: Fanzone, Martín Leandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria Mendoza. Laboratorio de Aromas y Sustancias Naturales; ArgentinaFil: Jofre, Viviana Patricia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria Mendoza. Laboratorio de Aromas y Sustancias Naturales; ArgentinaFil: Aredes Fernández, Pedro Adrián. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

First report of Cystoisospora belli parasitemia in a patient with acquired immunodeficiency syndrome

Cystoisospora belli in patients with the acquired immunodeficiency syndrome (AIDS) has been described as cause of chronic diarrhea and disseminated cystoisosporosis. Diagnosis of intestinal cystoisosporosis can be achieved at the tissue level in the villus epithelium of the small bowel. Disseminated cystoisosporosis is diagnosed by microscopy identification of unizoite tissue cysts in the lamina propria of the intestine. We report a case of disseminated cystoisosporosis in a human immunodeficiency virus (HIV)-infected patient with detection of parasitemia. We studied a 39-year old patient with AIDS and chronic diarrhea by analysis of stool and duodenal biopsy samples. Blood samples were also collected and examined by light microscopy and molecular techniques for C. belli DNA detection. The unizoite tissue cyst stages were present in the lamina propria, with unsporulated oocysts in feces. Zoites were present in blood smears and DNA of C. belli was detected in blood samples. Our study identified a new stage in the life cycle of C. belli. Detection of parasitemia is a novel and noninvasive tool for diagnosis of disseminated cystoisosporosis.Fil: Velásquez, Jorge Néstor. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: di Risio, Cecilia Alicia. Hospital Municipal General de Agudos Doctor José Penna; ArgentinaFil: Etchart, Cristina Beatriz. Hospital Municipal General de Agudos Doctor José Penna; ArgentinaFil: Chertcoff, Agustín Víctor. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; ArgentinaFil: Nigro, Mónica Gabriela. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; ArgentinaFil: Pantano, María Laura. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; ArgentinaFil: Ledesma, Bibiana Alba. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; ArgentinaFil: Vittar, Natalia. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Carnevale, Silvana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin