Evaluación mediante HPLC-MS de la capacidad de producción de Aflatoxinas y Ocratoxina A por parte de 20 cepas de Aspergillus y Penicillium aisladas de compost

Este artículo aporta los resultados obtenidos tras realizar el aislamiento e identificación de los mohos presentes en muestras obtenidas en los distintos estadios de la producción de compost en dos plantas de compostaje catalanas (Blanes y Manresa), así como de muestras de compost final de distintos orígenes. Identificados los mohos, se evalúa la capacidad de producir aflatoxinas y ocratoxina A de las cepas pertenecientes a los géneros Aspergillus y Penicillium utilizando cromatografía HPLC-MS. Se concluye que ninguna de las cepas aisladas es capaz de producirlas

On the mechanism of Candida tropicalis biofilm reduction by the combined action of naturally-occurring anthraquinones and blue light

The photoprocesses involved in the photo-induced Candida tropicalis biofilm reduction by two natural anthraquinones (AQs), rubiadin (1) and rubiadin-1-methyl ether (2), were examined.Production of singlet oxygen (1O2) and of superoxide radical anion (O2·−) was studied. Although it was not possible to detect the triplet state absorption of any AQs in biofilms, observation of 1O2 phosphorescence incubated with deuterated Phosphate Buffer Solution, indicated that this species is actually formed in biofilms. 2 was accumulated in the biofilm to a greater extent than 1 and produced measurable amounts of O2·− after 3h incubation in biofilms.The effect of reactive oxygen species scavengers on the photo-induced biofilm reduction showed that Tiron (a specific O2 ·− scavenger) is most effective than sodium azide (a specific 1O2 quencher). This suggests that O2 ·− formed by electron transfer quenching of the AQs excited states, is the main photosensitizing mechanism involved in the photoinducedantibiofilm activity, whereas 1O2 participation seems of lesser importance.Fil: Marioni, Juliana. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; 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; ArgentinaFil: Bresolí Obach, Roger. Universitat Ramon Llull; EspañaFil: Agut, Montserrat. Universitat Ramon Llull; EspañaFil: Comini, Laura 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 Químicas. Departamento de Farmacia; ArgentinaFil: Cabrera, Jose Luis. 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 Químicas. Departamento de Farmacia; ArgentinaFil: Paraje, María Gabriela. 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; ArgentinaFil: Nonell, Santi. Universitat Ramon Llull; EspañaFil: Núñez Montoya, Susana Carolina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; 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

Importance of Tetrahydroiso α-acids to the microbiological stability of beer

Producción CientíficaWhile beer provides a very stable microbiological environment, a few niche microorganisms are capable of growth in malt, wort, and beer. The production of off-flavors and development of turbidity in the packaged product are due to the growth and metabolic activity of wild yeast, certain lactic acid bacteria (LAB) and anaerobic Gram-negative bacteria. Beer also contains bitter hop compounds, which are toxic to Gram-positive and Gram-negative bacteria, and contribute to preventing the spoilage of this beverage. In the boiling process, the hop -acids (humulones) are isomerized into iso -acids. These products are responsible for the bitter taste of beer, but they also play an essential role in enhancing foam stability. Antibacterial activity of iso -acids and their hydrogenated derivates (rhoiso -acids and tetrahydroiso -acids) in MRS broth and beer have been evaluated against different LAB (Lactobacillus and Pediococcus) for the determination of their beer-stabilizing capabilities. Besides this, we have determined the minimum inhibitory concentration and the bacteriostatic effect of each compound against Pediococcus. We found that tetrahydroiso-acids (added directly to beer during production processes) are the compounds that present the greatest antibacterial activity against the main agents implicated in beer spoilage

A combination of photodynamic therapy and antimicrobial compounds to treat skin and mucosal infections: A systematic review

Background: Antimicrobial photodynamic therapy (aPDT) is a growing approach to treat skin and mucosal infections. Despite its effectiveness, investigators have explored whether aPDT can be further combined with antibiotics and antifungal drugs. Objective: To systematically assess the in vivo studies on the effectiveness of combinations of aPTD plus antimicrobials in the treatment of cutaneous and mucosal infections. Materials and methods: Searches were performed in four databases (PubMed, EMBASE, Cochrane library databases, ClinicaTrials.gov) until July 2018. The pooled information was evaluated according to the PRISMA guidelines. Results: 11 full-text articles were finally evaluated and included. The best aPDT combinations involved 5-aminolevulinic acid or phenothiazinium dye-based aPDT. In general, the combination shows benefits such as reducing treatment times, lowering drug dosages, decreasing drug toxicity, improving patient compliance and diminishing the risk of developing resistance. The mechanism of action may be that first aPDT damages the microbial cell wall or membrane, which allows better penetration of the antimicrobial drug. Limitations: The number of studies was low, the protocols used were heterogeneous, and there was a lack of clinical trials. Conclusions: The additive or synergistic effect of aPDT combined with antimicrobials could be promising to manage skin and mucosal infections, helping to overcome the microbial drug resistance

Levysahauksen rationalisointi : case: Domus Yhtiöt Oy

Työn aiheena oli levysahauksen rationalisointi, joka tehtiin Kouvolassa sijaitsevalle Domus Yhtiöt Oy:n kalusteyksikölle. Kalusteyksikkö valmistaa keittiö- ja kylpyhuonekalusteita sekä tilajärjestelmiä. Teoriaosuus sisältää tietoa tuotannonohjauksesta, rationalisoinnista ja varastoinnista. Lisäksi teoriaosuudessa on esitelty Domus Yhtiöt Oy:ta ja kalusteyksikön toimintaa. Tutkimusosuutta varten työntekijöitä haastateltiin, valkoisia kalustelevyjä sahaavan levysahan kapasiteetti määriteltiin karkeasti ja koneistusta edeltävän välivaraston levymääriä seurattiin kerran viikossa kymmenen viikon ajan. Saadut tiedot kirjattiin ylös, ja niitä arviotiin. Tietojen pohjalta valkoisten levyjen sahaukseen suunniteltiin kaksi kehitysehdotusta. Tavoitteena oli kartoittaa levysahauksen nykytilanne ja miettiä vaihtoehtoisia, käyttökelpoisia ja nykyistä tehokkaampia vaihtoehtoja sahausjärjestelylle. Ensimmäinen kehitysehdotus perustuu ns. 80/20 sääntöön ja se mm. vähentäisi välivarastoon sahattavien erilaisten levymittojen määrää. Toinen kehitysehdotus perustuu levyjen sahaamisen tilauskannan mukaan. Ehdotus parantaa materiaalivirran sujuvuutta, selkeyttää sahatyöntekijän toimintaa ja voi tuoda pieniä taloudellisia säästöjä kuten ensimmäinenkin kehitysehdotus. Työssä saavutettiin sille asetetut tavoitteet.The objective of this thesis was to improve and rationalize particle board cutting at Domus, a Finnish kitchen furniture manufacturer in Kouvola, and develop new plans for particle board cutting. The theory part of the thesis includes general information about production management, rationalization and storing. It also presents background information about the company and its furniture plant. In the practical part, employees were interviewed, the capacity of the panel saw was roughly estimated and the number of panels in the intermediate storage was counted every week for ten weeks. Next, results were estimated and a few alternative methods were developed. The target was to find out the current situation of sawing white melamine-laced particte boards and to present new, better cutting methods that can be taken to use. The target was achieved. The first new cutting method is based on the 80/20 rule. In this method the number of the parts of different sizes should decrease in the intermediate storage. The second new method is based on effective monitoring of order backlog. It improves the material flows, simplifies the saw operator’s work and can provide small financial savings, like the first method presented

Zinc-substituted myoglobin is a naturally occurring photoantimicrobial agent with potential applications in food decontamination

Zinc-substituted myoglobin (ZnMb) is a naturally-occurring photosensitizer that generates singlet oxygen with a high quantum yield. Using a combination of photophysical and fluorescence imaging techniques, we demonstrate the interaction of ZnMb with Gram positive Staphylococcus aureus and Gram negative Escherichia coli. An efficient antibacterial action against S. aureus was observed, with a reduction up to 99.9999% in the number of colony forming units, while no sizeable effect was detected against E. coli. Since ZnMb is known to form during the maturation of additive-free not-cooked cured ham, the use of this protein as built-in photodynamic agent may constitute a viable method for the decontamination of these food products from Gram-positive bacteria

NanoSOSG: A Nanostructured Fluorescent Probe for the Detection of Intracellular Singlet Oxygen

A biocompatible fluorescent nanoprobe for singlet oxygen (1O2) detection in biological systems was designed, synthesized, and characterized, that circumvents many of the limitations of the molecular probe Singlet Oxygen Sensor Green® (SOSG). This widely used commercial singlet oxygen probe was covalently linked to a polyacrylamide nanoparticle core using different architectures to optimize the response to 1O2. In contrast to its molecular counterpart, the optimum SOSG-based nanoprobe, which we call NanoSOSG, is readily internalized by E. coli cells and does not interact with bovine serum albumin. Furthermore, the spectral characteristics do not change inside cells, and the probe responds to intracellularly generated 1O2 with an increase in fluorescence

A comparative study on two cationic porphycenes: photophysical and antimicrobial photoinactivation evaluation

Over the last decades, the number of pathogenic multi-resistant microorganisms has grown dramatically, which has stimulated the search for novel strategies to combat antimicrobial resistance. Antimicrobial photodynamic therapy (aPDT) is one of the promising alternatives to conventional treatments based on antibiotics. Here, we present a comparative study of two aryl tricationic porphycenes where photoinactivation efficiency against model pathogenic microorganisms is correlated to the photophysical behavior of the porphycene derivatives. Moreover, the extent of photosensitizer cell binding to bacteria has been assessed by flow cytometry in experiments with, or without, removing the unbound porphycene from the incubation medium. Results show that the peripheral substituent change do not significantly affect the overall behavior for both tricationic compounds neither in terms of photokilling efficiency, nor in terms of bindin