Phenolic compounds from wines as natural preservative of fish meat

The aims of this work were to investigate the antibacterial effect of phenolic compound combinations and total polyphenols of Argentinean red wines varieties against Escherichia coli ATCC 35218 and Listeria monocytogenes using commercial fish meat as model food. Rutin- quercetin combination and the three wine varieties produced cellular death of both bacteria on fish meat at 4 oC. Rutin-quercetin combination was effect even at 20 °C on fish meat. Clarified wines were inactive against both bacteria, indicating that the responsible of observed effect were the polyphenols of wines. The use of wine phenolic compounds as antibacterial agent could be used to prevent contamination and extend the shelf life of fish meat. A big finding of this work is the use of rutin–quercetin combination as preservative during the transport and conservation of fish meat to the fish market, which is an effective antibacterial agent even when there is an Interrupted in the cold chain.Fil: Rodriguez Vaquero, Maria Jose. Universidad Nacional de Tucuman. Facultad de Bioquimica, Quimica y Farmacia. Instituto de Microbiologia; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Centro de Referencia Para Lactobacilos (i); Argentina;Fil: Aredes Fernández, Pedro Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Centro de Referencia Para Lactobacilos (i); Argentina;Fil: Manca, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Centro de Referencia Para Lactobacilos (i); Argentina

Biological activity of phenolic compounds from argentinean herbs infusions

Argentinean herbal infusions were studied for their beneficial biological properties and secondary metabolites content, such as phenolic compounds in order to find new natural products beneficial. The modifications of antihypertensive and antioxidant activities by the addition of commonly used additives (lemon, sugar and sweetener) were studied also. Ilex paraguaiensis infusion showed the highest concentration of phenolic compounds and flavonoid fraction, the supplementation with lemon juice increased the phenolic compound content. All infusion showed high DPPH radical scavenging assays and additives did not modify significantly this activity. The infusion of I. paraguaiensis presents the maximum viability reduction of Escherichia coli and Staphylococcus aureus and the herbs combination Lippia integrifolia-Ilex paraguaiensis was the most effective to reduce S. aureus and E.coli viability. The phenolic compounds concentration as well as the qualitative composition of each infusion plays an important role in the antimicrobial activity. Because the high correlation between the concentration of total phenolic compounds and antioxidant and antihypertensive activities, we can infer that the phenolic compounds are responsible for such activities. The results obtained allow us to propose the herbs studied as potential natural antioxidants and antihypertensive compounds that could be used in pharmaceutical and food industries.Fil: Rodriguez Vaquero, Maria Jose. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vallejo, Claudia Veronica. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aredes Fernández, Pedro Adrián. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Inactivation of Listeria monocytogenes and Salmonella Typhimurium in strawberry juice enriched with strawberry polyphenols

BACKGROUND: Low molecular-weight phenolic fractions (LMPFs) were extracted from Albion (LMPF-A) and Camarosa (LMPF-C) strawberry cultivars. Their antibacterial activity against Listeria monocytogenes and Salmonella Typhimurium cocktails in vitro and in vivo was investigated using strawberry juice as a food model. This study also sought to determine their antibacterial mechanism. RESULTS: Quercetin was identified as a principal compound in both phenolic fractions. The minimum bactericide concentration (MBC) values were 750 and 850 μg mL−1 (LMPF-C) and 800 and 950 μg mL−1 (LMPF-A) against S.Typhimurium and L. monocytogenes, respectively. The possible antibacterial activity of the phenolic extracts could be related to the release of phosphate and potassium ions, the effect of the disruption of membrane integrity on L. monocytogenes, and the effect of the inhibition of dihydronicotinamide adenine dinucleotide (NADH) oxidase activity on S. Typhimurium. Quercetin and kaempferol were the most active compounds in producing bacterial damage. Strawberry juice supplemented with the phenolic fractions and incubated at 37, 20, and 4 °C reduced bacterial viability; moreover, after treatment with the phenolic fraction at the lowest temperature, no viable cells were detected after 7 days’ incubation. Salmonella was more sensitive to the supplements than Listeria in strawberry juice. CONCLUSIONS: This study could form the basis for the development of natural antibacterial agents that could be included in natural juice or used by the pharmaceutical industry.Fil: Vallejo, Claudia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; ArgentinaFil: Minahk, Carlos Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Rollan, Graciela Celestina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Rodriguez Vaquero, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; Argentin

Isolation and identification of Homolactic bacteria from Solanum melongena L. with antibacterial activity that improve vegetable fermentation

The aim of this work was the isolation and identification of lactic acid bacteria with homolactic metabolism from eggplant; the lactic acid production and antibacterial activity were adopted as selected criteria to be included in the elaboration of fermented carrots as starter cultures. Between 50 isolated colonies, 14 were identified as lactic acid bacteria with homolactic metabolism, but only lactic acid bacteria identified phenotypic and genotypic as Lactobacillus plantarum were effective to produce cellular death and inhibit biofilm formation of five pathogenic bacteria. L. plantarum SB1 and SB2 were included in carrot fermentation on the basis of the best lactic acid production, antibacterial activity as well as the lowest C4 compounds and H2S formation. The scalded process was not enough effective to reduce Gram negative bacteria, but the addition of the selected bacteria isolated from eggplant to fermentation was effective to reduce all Gram negative population at 7 day. The big finding of this work was the isolation and identification of L. plantarum SB1 and SB2 from eggplant that could adapted in an different ecological niche and their addition to fermented carrots increase stability and microbiological safety of final product, preventing infectious diseases, with optimal sensorial attributed.Fil: Rodriguez Vaquero, Maria Jose. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Perato, Silvia Marisa. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Rivero, Luciana del Valle. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Saguir, Fabiana M.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

Characterization, antibacterial and biological activities of phenolic fraction of argentinean red wines

For the first time, the qualitative and quantitative characterization of phenolic compounds of lower molecular weight fraction (LMF) were evaluated in commercial Cabernet Sauvignon (CS) and Tannat (T) wines varieties produced in Cafayate, Argentine. The antimicrobial activity against Pediococcus pentosaceus 12p, spoilage wine bacteria as well as the “in vitro” antioxidant and antihypertensive activities were also evaluated. The composition of LMF obtained by liquidliquid extraction with ethyl acetate, determined by HPLC-DAD, showed a total content of phenolic compounds of 229.4 and 311.1 mg L-1 for CS and T wines respectively. Synthetic like-wine media (SWM), pH 4.5 supplemented with LMF at identical concentration of the wine (1X), four (4X) and eight times concentrated (8X), was inoculated with P. pentosaceus 12p at 107CFU mL-1. Samples were collected at the beginning and final incubation time to determine cell viability in MRS-agar medium and the damage of the cell membrane integrity by electron microscopy observation. In the presence of LMF at 1X concentration, both fractions diminish growth parameters without cellular damage. In the presence of LMF of CS and T wine varieties four and eight times concentrated, cellular death of the microorganism as well as plasmatic membrane disruption was observed. The LMF of both wines analyzed in this study have high antioxidant, radical scavenging and antihypertensive activity. The use of phenolic compounds as potential antimicrobial agents could be an effective additive to controll wine spoilage bacteria, adding on wines beneficial properties to human health.Fil: Stivala, Maria Gilda. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Villecco, Margarita B.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Fanzone, Martín. Instituto Nacional de Tecnologia Agropecuaria. Centro Reg.cuyo Mendoza-san Juan. Estacion Exptal.agrop.mendoza. Laboratorio de Aromas y Sustancias Naturales; ArgentinaFil: Jofré, Viviana. Instituto Nacional de Tecnologia Agropecuaria. Centro Reg.cuyo Mendoza-san Juan. Estacion Exptal.agrop.mendoza. Laboratorio de Aromas y Sustancias Naturales; ArgentinaFil: Rodriguez Vaquero, Maria Jose. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aredes Fernández, Pedro Adrián. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Capacidad inhibitoria del escobajo, desecho de la industria vitivinícola, sobre cepas de (candida albicans) aisladas de pacientes con candidiasis vulvovaginal

Introducción. La Candidiasis Vulvovaginal (CVV) es una infección micótica de alta incidencia y recurrencia que causa dolor, irritación y prurito en la zona afectada. El 75% de las mujeres sufren por lo menos un episodio a lo largo de su vida. El agente etiológico más frecuente es Candida albicans. El tratamiento consiste principalmente en el uso de azoles antifúngicos, que provocan numerosos efectos secundarios y aparición de cepas resistentes. Por lo tanto, la búsqueda de nuevos agentes antimicóticos es necesaria y una posible fuente la representan los metabolitos de los residuos de la industria vitivinícola. El escobajo, material vegetal que soporta el racimo de la uva, conserva junto con el orujo un alto contenido de polifenoles luego del proceso de elaboración del vino.Objetivo. Evaluar la capacidad inhibidora de los extractos ricos en compuestos fenólicos del escobajo, residuo de la industria vitivinícola, sobre cepas de Candida albicans aisladas de muestras clínicas. Metodología. El extracto de escobajo (EE) se obtuvo por extracción continua en Soxhlet usando etanol como solvente. Se cuantificaron los compuestos fenólicos totales del EE y se evaluó su toxicidad sobre la viabilidad, el desarrollo larval y la reproducción de Caenorhaditis elegans. Se determinó la actividad antifúngica in vitro del EE (400, 600 y 800 µg/mL) sobre 2 cepas de Candida albicans (IBL001 e INM982891) mediante métodos de difusión en agar y de entrecruzamiento. Se determinó la capacidad del EE para inhibir el crecimiento (CIM) y la formación de biofilm de ambas cepas de C. albicans. La capacidad protectora de la muerte causada por cándida se estudió in vivo sobre el nematodo C. elegans infectado con IBL001 y INM982891.Resultados. El rendimiento del EE fue de 15%, lo que indica que la técnica de extracción utilizada fue apropiada. El EE inhibió el crecimiento de ambas cepas de C. albicans ensayadas (CIM 650 µg/mL) y la formación del biofilm por las mismas en ∼90%. Por otro lado, no alteró la viabilidad, el desarrollo normal ni la reproducción de C. elegans a las concentraciones ensayadas. El EE redujo en un 18% la muerte causada por la infección con las cepas IBL001 e INM982891 en el nematodo, utilizando 400 y 800 µg/mL, respectivamente para cada una. Este efecto fue similar al efecto protector de 1 mg/mL de Fluconazol, usado como control. Conclusiones. El EE fue efectivo para inhibir in vitro el crecimiento y el biofilm de dos cepas de C. albicans aisladas de pacientes con vulvovaginitis. Este efecto se vio reflejado en el ensayo in vivo, protegiendo al nematodo de la muerte causada por el patógeno. Dada la necesidad de encontrar nuevos agentes antimicóticos para el tratamiento de CVV causada por C. albicans, y de hallar formas alternativas de revalorizar y utilizar los desechos de las industrias ricos en metabolitos activos, el extracto de escobajo demostró tener actividad antifúngica para ser explotada en el desarrollo de nuevos antimicóticos.Fil: D'almeida, Romina Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Vallejo, Claudia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; ArgentinaFil: Perez Merello, Mercedes. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; ArgentinaFil: Vera, María Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Villena, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Vizoso Pinto, María Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Rodriguez Vaquero, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; ArgentinaXV Congreso Argentino de Microbiología; V Congreso Argentino de Microbiología de Alimentos V Congreso Latinoamericano de Microbiología de Medicamentos y Cosméticos; XIV Congreso Argentino de Microbiología GeneralCiudad Autónoma de Buenos AriesArgentinaAsociación Argentina de Microbiologí

Early Tracheostomy for Managing ICU Capacity During the COVID-19 Outbreak: A Propensity-Matched Cohort Study

10 p.Background: During the first wave of the COVID-19 pandemic, shortages of ventilators and ICU beds overwhelmed health care systems. Whether early tracheostomy reduces the duration of mechanical ventilation and ICU stay is controversial. Research question: Can failure-free day outcomes focused on ICU resources help to decide the optimal timing of tracheostomy in overburdened health care systems during viral epidemics? Study design and methods: This retrospective cohort study included consecutive patients with COVID-19 pneumonia who had undergone tracheostomy in 15 Spanish ICUs during the surge, when ICU occupancy modified clinician criteria to perform tracheostomy in Patients with COVID-19. We compared ventilator-free days at 28 and 60 days and ICU- and hospital bed-free days at 28 and 60 days in propensity score-matched cohorts who underwent tracheostomy at different timings (≤ 7 days, 8-10 days, and 11-14 days after intubation). Results: Of 1,939 patients admitted with COVID-19 pneumonia, 682 (35.2%) underwent tracheostomy, 382 (56%) within 14 days. Earlier tracheostomy was associated with more ventilator-free days at 28 days (≤ 7 days vs > 7 days [116 patients included in the analysis]: median, 9 days [interquartile range (IQR), 0-15 days] vs 3 days [IQR, 0-7 days]; difference between groups, 4.5 days; 95% CI, 2.3-6.7 days; 8-10 days vs > 10 days [222 patients analyzed]: 6 days [IQR, 0-10 days] vs 0 days [IQR, 0-6 days]; difference, 3.1 days; 95% CI, 1.7-4.5 days; 11-14 days vs > 14 days [318 patients analyzed]: 4 days [IQR, 0-9 days] vs 0 days [IQR, 0-2 days]; difference, 3 days; 95% CI, 2.1-3.9 days). Except hospital bed-free days at 28 days, all other end points were better with early tracheostomy. Interpretation: Optimal timing of tracheostomy may improve patient outcomes and may alleviate ICU capacity strain during the COVID-19 pandemic without increasing mortality. Tracheostomy within the first work on a ventilator in particular may improve ICU availability

Relationship between olive oil consumption and ankle-brachial pressure index in a population at high cardiovascular risk

Background and aims: The aim of this study was to ascertain the association between the consumption of different categories of edible olive oils (virgin olive oils and olive oil) and olive pomace oil and ankle-brachial pressure index (ABI) in participants in the PREDIMED-Plus study, a trial of lifestyle modification for weight and cardiovascular event reduction in individuals with overweight/obesity harboring the metabolic syndrome. Methods: We performed a cross-sectional analysis of the PREDIMED-Plus trial. Consumption of any category of olive oil and olive pomace oil was assessed through a validated food-frequency questionnaire. Multivariable linear regression models were fitted to assess associations between olive oil consumption and ABI. Additionally, ABI ≤1 was considered as the outcome in logistic models with different categories of olive oil and olive pomace oil as exposure. Results: Among 4330 participants, the highest quintile of total olive oil consumption (sum of all categories of olive oil and olive pomace oil) was associated with higher mean values of ABI (beta coefficient: 0.014, 95% confidence interval [CI]: 0.002, 0.027) (p for trend = 0.010). Logistic models comparing the consumption of different categories of olive oils, olive pomace oil and ABI ≤1 values revealed an inverse association between virgin olive oils consumption and the likelihood of a low ABI (odds ratio [OR] 0.73, 95% CI [0.56, 0.97]), while consumption of olive pomace oil was positively associated with a low ABI (OR 1.22 95% CI [1.00, 1.48]). Conclusions: In a Mediterranean population at high cardiovascular risk, total olive oil consumption was associated with a higher mean ABI. These results suggest that olive oil consumption may be beneficial for peripheral artery disease prevention, but longitudinal studies are needed

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Human health benefits, antimicrobial properties and the future of phenolic compounds as preservatives in the food industry

Phenolic compounds are found in fruit, vegetables, nuts, seeds, stems and flowers as well as tea, wine, propolis and honey, and represent a common constituent of the human diet. Dietary flavonoids have attracted interest because they have a variety of beneficial biological properties, which may play an important role in the maintenance of human health. Flavonoids are potent antioxidants, free radical scavengers and metal chelators; they inhibit lipid peroxidation and exhibit various physiological activities including anti-inflammatory, antiallergic, anticarcinogenic, antihypertensive, antiarthritic and antimicrobial activities. Consumption of phenol-rich beverages, fruit and vegetables has commonly been associated to a reduction of the risk of cardiovascular diseases in epidemiological studies and the regular consumption, during several weeks or months, was shown to reduce cholesterolemia, and oxidative stress. The total polyphenols amounts determined from the same plant and their corresponding antioxidant and antimicrobial activities may vary widely, depending on extraction conditions applied. Food contamination and spoilage by microorganisms are a serious problem because they have not yet been brought under adequate control despite the news preservation techniques available.  Food-borne illness resulting from consumption of food contaminated with pathogenic bacteria has been of vital concern to public health. Unfortunately there is a dramatic increase throughout the world in the number of reported cases of food-borne illness. To reduce the incidence of food poisoning and spoilage by pathogenic microorganisms many synthetic chemicals were utilized. The exploration of natural antimicrobials for food preservation receives increased attention due to consumer awareness of natural food products and a growing concern of microbial resistance towards conventional preservatives. The use of phenolic compounds as antimicrobial agents would provide an additional benefits, including dual-function effects of both preservation and delivery health benefits.  Knowing the antimicrobial effect of the phenolic compounds from vegetables on the principal pathogenic microorganisms from the different foods, it is possible to search strategies to combine the synergic antimicrobial effects of phenolic compounds with their natural biological properties. The results will permit to formulate new products to be used as food preservatives or to be included in the human diet.Fil: Manca, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Rodriguez Vaquero, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin