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Given that Staphylococcus aureus, an opportunistic pathogen, is one of the main etiological agents that causes various hospital and community infections associated with the production of virulence factors, emerging treatment strategies target to attenuate the activity of these factors can be promising to combat antibiotic-resistant strains. In this perspective, we investigated the antipathogenic potential against three S. aureus strains of chloroform extracts of cell-free culture supernatant from the probiotic bacteria Lactobacillus casei and Lactobacillus acidophilus, as well as its suitability as an alternative antimutagenic agent. Both extracts did not display antibacterial activity but significantly reduced the bacterial biofilm formation at different stages 3 h (up to 73%), 6 h (up to 45%), and 24 h (up to 46%). Moreover, the extracts decrease the virulence factors production, hemolysin (up to 67%), and coagulase (delayed coagulation), as well as the cell metabolism in the biofilm (up to 65%), disrupting a preformed biofilm (up to 46%), all devoid of affecting its growth suggesting that the inhibition could be mediated by Quorum sensing (QS). The extract’s effect on biofilm disruption and metabolic activity seems to be strain dependent. The 2,5-diketopiperazines present in the extracts showed the ability to bind to the QS regulatory proteins SarA and AgrA in molecular docking studies. In the mutagenicity assay, both probiotic bacteria were able to remove the mutagen, and this capacity increased with the bacteria concentration.

The treatments being investigated for the pandemic associated with a severe acute respiratory syndrome caused by the new coronavirus (SARS-CoV2) aim to inhibit viral replication or inhibit enzymatic elastase in the lung, responsible for the SARS-CoV cell entry mechanism and the pathogenesis of severe pneumonia caused by infection There is also a need to improve alveolar surfactant capacity and inhibition of the exacerbated inflammatory response Current knowledge allows us to infer that Citrus essential oils could be considered an individual or a complementary highly valuable alternative for the viral infection caused by SARS-CoV due to its antiviral activity, particularly against coronavirus, anti-elastase, anti-inflammatory, antibacterial and antibiofilm properties Furthermore, its proven capacity of biosurfactants, antioxidants, and pain inhibitors would help to treat acute respiratory syndrome This review aims to encourage the development of more detailed studies on Citrus essential oils as a new multi-objective strategy to treat SARS-CoV2 infection Abbreviations: SARS-CoV: Severe Acute Respiratory Syndrome Coronavirus;GRAS: Generally Recognized as Safe;TRP: Transient Receptor Proteins;HeLa-CEACAM1a: HeLa-epithelial carcinoembryonic antigen-related cell adhesion molecule 1a;HSV: Herpes Simplex Virus;FDA: Food and Drug Administration;ANMAT: National Administration of Medicines, Food and Medical Technology, Argentina;AFSSAPS: Agence Francaise de Securite Sanitaire des Produits de Sante, France;ACE2:Angiotensin-converting enzyme-2 [ABSTRACT FROM AUTHOR] Copyright of Journal of Essential Oil Research is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission However, users may print, download, or email articles for individual use This abstract may be abridged No warranty is given about the accuracy of the copy Users should refer to the original published version of the material for the full abstract (Copyright applies to all Abstracts )

This work investigated chloroform extracts from culture supernatants of two human probiotic bacteria, Lactobacillus casei CRL 431 and Lactobacillus acidophilus CRL 730 for the production of virulence factors and quorum sensing (QS) interference against three Pseudomonas aeruginosa strains. Both extracts inhibited biofilm biomass (up to 50%), biofilm metabolic activity (up to 39%), the production of the enzyme elastase (up to 63%) and pyocyanin (up to 77%), and decreased QS, without presenting any antibacterial acgivity. In addition, the chloroform extracts of both strains disrupted preformed biofilms of the three strains of P. aeruginosa analyzed (up to 40%). GC-MS analysis revealed that the major compounds detected in the bioactive extracts were four diketopiperazines. This study suggests that the metabolites of L. casei and L. acidophilus could be a promising alternative to combat the pathogenicity of P. aeruginosa.

The study of two new acylthiourea derivatives (Ar-CO-NH-CS-NH-R) are focused on the bonding interactions supported by X-ray, NMR, UV-Vis, Raman and IR spectroscopy, and NBO, AIM and Hirshfeld surface analysis. The RAHB model is proposed to explain some structural properties. The molecules are stabilized by intra-molecular NH⋯O bonds arranged in the lattice as centre-symmetric dimers held by inter-molecular NH⋯S bonds. The dimers are linked to each other through NH⋯O bonds giving rise to a chain, ribbon-like structure in the network. In vitro bacterial growth inhibition, biofilm formation, biosensor and biofilm metabolic activity were tested considering the broad bioactivity of acylthioureas. Fil: Contreras Aguilar, Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentina Fil: Echeverría, Gustavo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Piro, Oscar Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Ulic, Sonia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentina. Universidad Nacional de Luján; Argentina Fil: Jios, Jorge Luis. Comision de Investigaciones Cientificas de la Provincia de Buenos Aires. Unidad Plapimu Laseisic.; Argentina Fil: Tuttolomondo, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Molina, Rocío Daniela Inés. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina

Antimicrobial, antibiofilm, anti-Quorum sensing (QS) and virulence factors inhibitory capacity of different polarity Laurus nobilis extracts against several pathogenic microorganisms were studied. Some extracts exhibited antibiotic effect against Staphylococcus aureus multidrug-resistant strains. However, all extracts (100 µg/mL) inhibited to some extent the biofilm of most bacteria tested (until 40% for Gram-negative and 76% for Gram-positive). Hexane (HE) and chloroform extract (CE) were potent inhibitors of S. aureus biofilm and the microscopies further confirmed an important reduction in adherent cells. Polystyrene surfaces coated with these extracts showed a decrease in bacterial adhesion with the resulting inhibition of S. aureus biofilm formation and biofilm activity. Moreover, they also interfere with the coagulase and hemolysin activities of this bacterium. With respect to Gram-negative bacteria, these extracts showed anti-QS activity against Chromobacterium violaceum and inhibited biofilm formation, swarming motility, pyocyanin production, and elastase activity of Pseudomonas aeruginosa. Chemical analysis of HE and CE revealed that the fatty acids were the main compounds, particularly linolenic, oleic and hexadecanoic acids followed by the oxygenated monoterpenes. Non-toxic laurel extracts offer a natural alternative to control contamination and/or spoilage of food, as well as infectious diseases, by attacking the biofilm and the virulence of Gram-positive and Gram-negative bacteria. Fil: Molina, Rocío Daniela Inés. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Campos Silva, Rodrigo. Universidade Federal do Rio Grande do Sul; Brasil Fil: Díaz, Myriam Anabel. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Macedo, Alexandre José. Universidade Federal do Rio Grande do Sul; Brasil Fil: Blázquez, María Amparo. Universidad de Valencia; España Fil: Alberto, Maria Rosa. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

The effect of a natural sesquiterpene ketone, 9,10-dehydrofukinone (DHF), on pathogenic Staphylococcus aureus and Pseudomonas aeruginosa strains isolated from chronic infectious processes, was the focus of the present study. Lipophilic DHF produced important antibacterial synergistic effects in association with ciprofloxacin (CPX) against two biofilm-forming strains of S. aureus HT1 (FIC=0.21) and P. aeruginosa HT5 (FIC=0.05). Hence, this mixture constitutes an excellent strategy to combat these biofilm-producing bacteria that overexpress drug efflux pumps as a resistance mechanism. Additionally, a substantial rise in beneficial Lactobacillus biofilm biomass was determined as a very significant finding of this association. Particularly, a non-pathogenic biofilm increment of 119% was quantified when the mixture was added to a probiotic L. acidophilus ATCC SD-5212 culture. A surface activity enhanced in 71% with respect to untreated L. acidophilus culture was also generated by the DHF and CPX association, and therefore, a glycoprotein synthesis induction mediated by the mixture is discussed. The results obtained could help in the development of new selective antibiotics. From an ecological standpoint, the present study strongly suggests that DHF is a polyfunctional organic molecule produced with a high yield in Senecio punae that exerts a positive impact on a non-pathogenic plant bacterium L. plantarum CE105. Fil: Verni, Maria Cecilia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Garay, José A.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Mendoza, Lucía. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Bardón, Alicia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Borkosky, Susana Alicia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

En la industria de alimentos, el biofilm es la principal causa de contaminación. Debido a normativas alimentarias, solo pocos compuestos pueden ser usados como conservantes o estar en contacto con alimentos durante su elaboración y a la vez deben ser económicos. Una alternativa es el uso de subproductos o residuos de agroindustrias. Una de las principales industrias alimenticias de Iberoamérica es la vitivinicultura. La presente investigación utiliza orujo y escobajo de vino varietal Torrontés para inhibir la virulencia bacteriana controlada por Quorum sensing (QS) y principalmente su motilidad (swarming y swimming), lo que permitiría el desplazamiento y la formación de biofilm en alimentos. Realizamos extracciones con solventes de polaridad creciente (hexano, cloroformo, acetato de etilo y metanol). Enfrentamos 250 y 500 μg/ml de extractos (E) a las cepas de Pseudomonas aeruginosa ATCC 27853 y LVP65. Los E metanólicos de orujo y escobajo inhibieron más del 50 la motilidad swarming de ambas cepas. Los E acetato de etilo inhibieron swimming (25-30 %). La actividad anti-QS de los E se ensayó con las cepas Chromobacterium violaceum ATCC 12472 y CV026 y se determinó una inhibición de los E metanólicos y de acetato sobre el sistema de QS. Las bioactividades encontradas convierten a estos desechos en una novedosa alternativa para la preservación de alimentos. In the food industry, biofilm is the main cause of contamination. Due to food regulations, only a few compounds can be used as preservatives or be in contact with food during their prepara-tion and, at the same time, they must be economical. An alternative is the use of by-products or agro-industry waste. One of the main food industries in Latin America is viticulture. The present research uses marc and stems of Torrontés varietal wine to inhibit the bacterial virulence controlled by Quorum sensing (QS) and its motility (swarming and swimming), which would allow the displacement and formation of biofilm in foods. We perform extractions with solvents of increasing polarity (hexane, chloroform, ethyl acetate, and methanol). We compare 250 and 500 μg / ml of extracts to the strains of Pseudomonas aeruginosa ATCC 27853 and LVP65. Methanolic extracts to marc and stems inhibited more than 50 swarming motility of both strains. In addition, both ethyl acetate extracts inhibited the swimming (25-30 %). The anti-QS activity of the Extracts was tested with strains Chromobacterium violaceum ATCC 12472 and CV026 and an inhibition of the methanolic and acetate extracts on the QS system was determined. The bioactivities found make a novel alternative for food preservation out of this waste. Fil: Viola, Carolina Maria. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Alberto, Maria Rosa. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

Capsicum annuum extracts of different polarities were tested for their antimicrobial, antibiofilm, and anti-Quorum sensing (QS) activity against several pathogenic microorganisms and possible toxic effects using an in vivo model (Galleria mellonella L.). Hexane (HE) and Chloroform extract (CE) were the most active in inhibiting biofilm formation of the eight bacteria tested, with inhibition percentages between 22 and 88% for a concentration of 100 μg/mL. These extracts were potent inhibitors of Staphylococcus aureus biofilm, and microscopy analysis confirmed a significant reduction in adhered cells. Moreover, polystyrene surfaces coated with these extracts decreased Staph. aureus adhesion resulting in biofilm formation and activity inhibition. In addition, they interfere with the hemolysin and coagulase activities. The extracts inhibited biofilm formation and swarming motility in Gram-negative bacteria. Furthermore, in Pseudomonas aeruginosa, elastase activity and pyocyanin production were reduced. In the most active extracts, the main compound was linoleic acid, followed by oleic and hexadecanoic acids. Paprika extracts capable of controlling bacterial virulence represent a promising alternative as a natural preservative to restrict contamination or spoilage of food.

Background: Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen, considered a leading cause of acute and chronic infections in immunocompromised patients. P. aeruginosa uses quorum sensing to control virulence and biofilm formation. To combat this human-resistant pathogen increasing attention has been paid to anti-QS compounds from natural products as potential therapeutic agents. Purpose: To assess the efficacy of C. paradisi (grapefruit) and C. reticulata (mandarin) commercial EOs (obtained by cold-pressing and cold-pressing followed by steam distillation, named EOP and EOPD, respectively) and their majority component, limonene, in inhibiting the effect of QS controlled virulence factors of P. aeruginosa PAO1 and PA14 in a C. elegans infection model. Results: C. paradisi and C. reticulata EOs at 0.125% (v/v) significantly inhibited the in vitro biofilm formation of PAO1 and PA14 strains between 40-50%. This EOs concentration, safe for C. elegans according to the survival and brood size assays, rescued the nematodes from P. aeruginosa infections, reducing their death rate by 20-30% in the paralysis assay, and increasing worm lifespan with median survivals of 6 and 5, respectively, in the slow killing assay (median survival of 3 for non-treated worms). Limonene protected nematodes from death in these assays although less effectively than both EOs species. Grapefruit EOs rescued the nematodes in 45-50% from phenazine-death, while mandarin EOs and limonene rescued them in 30%. In the food choice assay, worms felt more attracted to the PA14 grown with 0.125% of mandarin and grapefruit EOs or limonene spots (with CI=0.11 to 0.18). Conclusion: Our results suggest that C. paradisi and C. reticulata EOPDs, with lower commercial value but similar in vivo effects than EOPs, are sources of anti-QS agents for controlling P. aeruginosa infections, therefore should be considered as potential candidates for the development of novel therapeutics against persistent microorganisms.

The anti-pathogenic activity of Acantholippia deserticola, Haplopappus baylahuen, Lippia integrifolia and Satureja parvifolia herbs used as traditional infusion were investigated. The extracts obtained were compared with respect to chromatographic profiles and antimicrobial activities. The dichloromethane and methanol extracts of the four herbs showed significant inhibition of Staphylococcus aureus and Pseudomonas aeruginosa growth and biofilm formation. The dichloromethane extract of Lippia integrifolia that showed the highest inhibitory effect on P. aeruginosa biofilm formation, was fractionated by column chromatography using a gradient of polarity, and the activities of the fractions were evaluated. In general, the lower polar fractions inhibited biofilm in correlation with bacterial growth. However, in more polar fractions the biofilm diminution is well correlated with the inhibition of AI production more than the bacterial development. The results provide scientific support to the usage of these herbs for the protection against foodborne diseases through different mode of actions. This effect is notably in L. integrifolia due that the fractions showed superior growth, biofilm and autoinducer inhibitory activity compared to crude extract. Fil: Brodkiewitz, Ivana Yanina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Molina, Rocío Daniela Inés. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Vega López, Guillermo Alfredo. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Alberto, Maria Rosa. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina Fil: Vera, Nancy Roxana. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina

Entomopathogenic fungi are fungal organismsextensively used in various parts of the world asbiopesticides against insect pests that cause importanteconomic damage. Various secondary metabolitesproduced by these fungi have many potential biologicalactivities. The present study was undertaken to evaluatethe insecticidal activity of extracts and pure compoundsfrom Nomuraea rileyi (Farlow) Samsonentomopathogenic fungi against Spodoptera frugiperdaSmith (Lepidoptera), Ceratitis capitata Wiedemann(Diptera) and Tribolium castaneum Herbst (Coleoptera),three insect pests that generate serious economic losses inthe northwest of Argentina. Diketopiperazines wereextracted from the culture free supernatant of the mediawith ethyl acetate. Antifeedant properties were detected inall extracts under dietary choice conditions (300 ug/ g ofdiet). The maximum antifeedant activity was noted incycles (Pro-Val) (86.02) and cycle (Pro-Phe) (73.47),while the rest of the extracts and metabolites exhibitedvarying degrees of moderate or less toxic effects. Themaximum oviposition deterrence against C. capitata(55.86%) was recorded with cycle (Pro-Phe) at a 50µm/cm2 dose. Culture medium extracts supplementedwith insect remains and all pure compounds showedrepellent action against T. castaneum. The mainrepellency was observed in phenylacetic acid and cycle(Pro-Val) with RI values of 42 and 41% respectively. Thepresent study would suggest the possible utilization ofentomopathogenic fungal metabolites as an effectiveagent for controlling insect pests that cause importanteconomic losses. Fil: Marcinkevicius, Karenina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Salvatore, Silvana Analia. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria.; Argentina Fil: Vera, Nancy Roxana. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

A new series of CuII, NiII, CoII, and MnIII complexes have been synthesised from the (6Z)-6-(7-trifluoromethyl-1,2,3,4-tetrahydro-5H-1,4-diazepin-5-ylidene)cyclohexa-2,4-dien-1-one (HDZP) ligand. These complexes were characterised by elemental, spectroscopic (IR and UV-vis), and thermal analysis. The crystal structure of Cu-DZP was solved by X-ray diffraction methods. The complex crystallises in the monoclinic P21/c space group, with two molecules per unit cell. The crystal lattice is stabilised by different intra and intermolecular interactions. Hirshfeld surface analysis was employed to obtain additional information about interactions that are responsible for the crystal packing. Quantitative examination of the fingerprint plots indicated the dominant contribution of H⋯H and H⋯X (X = O, F) interactions in the crystal packing. In addition, C–H⋯chelate ring (CR) and C–H⋯π interactions are described in detail and evaluated using DFT calculations. The antibacterial properties and the mechanism of inhibition of the main bacterial resistant mechanism, the biofilm, of the metal complexes and free ligand were investigated. [Mn(DZP)₃]·2H₂O was the most active complex against the Pseudomonas aeruginosa biofilm formation with an inhibition of 40 %. However, none of the complexes inhibit more than 25 % of the Gram negative bacteria microbial development. The most meaningful result was the bactericidal effect of [Co(DZP)₂(H₂O)₂]·2H₂O against the Gram positive bacteria, Staphylococcus aureus, which inhibits the bacterial development and significantly reduces the biofilm formation at low concentration., Instituto de Física La Plata, Planta Piloto Multipropósito - Laboratorio de Servicios a la Industria y al Sistema Científico, Centro de Química Inorgánica

Citrus essential oils are used in food to confer flavor and aromas. The citrus essential oils have been granted as GRAS and could be used as antimicrobial additives to control bacterial quorum sensing from potential food bacterial pathogens. The chemical composition and inhibitory activity of Citrus paradisi (grapefruit) essential oils obtained by cold-pressed method (EOP) and cold-pressed method followed by steam distillation, against Pseudomonas aeruginosa were determined . The GC-MS analyses of the oil indicated the amount of the essential oil components was highest with D-limonene in both cases. However, the extraction method modified the chemical composition. EOP had higher amount of coumarins and flavonoid as well as less oxygenated terpenoids. At 0.1 mg/mL essential oils were not able to modify the bacterial development but inhibited the P. aeruginosa biofilm production between 52% and 55%, sessile viability between 45% and 48%, autoinducer production and elastase activity between 30% and 56%. Limonene was less effective at inhibiting P. aeruginosa than the essential oils, suggesting a synergistic effect of the minor components. According to our results, grapefruit essential oils could be used as a food preservative to control P. aeruginosa virulence.

Entomopathogenic fungi have an incredible capacity to produce biologically active metabolites. The present study was undertaken to evaluate the insecticidal activity of extracts, fractions and pure compounds from Fusarium sp. ARSEF 3300 entomopathogenic fungi against Spodoptera frugiperda Smith (Lepidoptera) and Ceratitis capitata Wiedemann (Diptera). Additionally, antimicrobial activity was determined against Staphylococcus aureus ATCC 6538 and Pseudomonas aeruginosa ATCC 27853. The culture media developed in the absence and presence of remains of the S. frugiperda insect were called fungus (H) and fungus-insect (HI), respectively. Volatile compounds in the extracts obtained with ethyl acetate were identified by GC-MS. Seven compounds of known chemical structure were isolated: cholesterol (1), campesterol (2), palmitic acid (3), cis-Oleic acid (4), stearic acid (5), ester propyl myristate (6) and cis-9, cis-12 Linoleic acid (7). The ethyl acetate extract of the HI supernatant of Fusarium sp., showed the highest ingestion dissuading activity in S. frugiperda (83% at 300 μg/g of diet) and the highest oviposition deterrence in C. capitata (50% at 50 μg/cm 2 ). Extracts of H and HI supernatants from Fusarium sp. inhibited the growth of the P. aeruginosa (53.64% and 45.39%) and S. aureus (76.08% and 79.61%) at 400 μg/mL. Palmitic acid (46.23% and 38.59%), cis-Oleic acid (49.95% and 42.33%) and stearic acid (50.44% and 39.72%) showed the highest inhibition of growth and biofilm production in S. aureus at 100 μg/mL. Our results suggest the possible utilization of entomopathogenic fungal metabolites in the control of insect pests and human health. Fil: Marcinkevicius, Karenina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Salvatore, Silvana Analia. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina Fil: Murúa, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Vera, Nancy. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

The chemical composition of three Citrus limon oils: lemon essential oil (LEO), lemon terpenes (LT) and lemon essence (LE), and their influence in the virulence factors production and motility (swarming and swimming) of two Pseudomonas aeruginosa strains (ATCC 27853 and a multidrug-resistant HT5) were investigated. The main compound, limonene, was also tested in biological assays. Eighty-four compounds, accounting for a relative peak area of 99.23%, 98.58% and 99.64%, were identified by GC/MS. Limonene (59–60%), γ-terpinene (10–11%) and β-pinene (7–15%) were the main compounds. All lemon oils inhibited specific biofilm production and bacterial metabolic activities into biofilm in a dose-dependent manner (20–65%, in the range of 0.1–4 mg mL−1) of both strains. Besides, all samples inhibited about 50% of the elastase activity at 0.1 mg mL−1. Pyocyanin biosynthesis decreases until 64% (0.1–4 mg mL−1) for both strains. Swarming motility of P. aeruginosa ATCC 27853 was completely inhibited by 2 mg mL−1 of lemon oils. Furthermore, a decrease (29–55%, 0.1–4 mg mL−1) in the synthesis of Quorum sensing (QS) signals was observed. The oils showed higher biological activities than limonene. Hence, their ability to control the biofilm of P. aeruginosa and reduce the production of virulence factors regulated by QS makes lemon oils good candidates to be applied as preservatives in the food processing industry. Fil: Luciardi, María Constanza. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Blázquez, María Amparo. Universidad de Valencia; España Fil: Alberto, Maria Rosa. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

Bis - (methylsulfonylmethyl) sulfone, BMSMS, was synthesized and characterized through vibrational (IR, Raman) spectroscopy. The crystal structure of BMSMS, determined by X-ray diffraction methods, together with Hirshfeld surfaces analysis were used to evaluate intermolecular interactions. BMSMS can be considered as one-turn helix of about 7.13 A, further stabilized by weak intra-molecular CH•••O bonds. The experimental results were supplemented by quantum chemical calculations. It was also analyzed the hyperconjugative effects of oxygen atoms lone pairs (LP) on the vibrational behavior of the SO2 group. Besides, biofilm formation and QS activity were evaluated on this new bis- (methylsulfonylmethyl) sulfone.

Bacterial spoilage of food and other infections are a coordinated mechanism controlled by quorum sensing (QS), which regulate the expression of virulence factors, such as biofilm. The antimicrobial, antibiofilm, anti-QS and anti-swarming properties of hexane (HE), chloroform (CE), ethyl acetate (EAE), methanolic (ME) and total methanolic (TME) extracts of coriander grown in Argentina were investigated. In vivo extracts toxicity using Galleria mellonella L. model and chemical composition (GC-MS) were also assessed. The antibiofilm activity of polystyrene surfaces coated with the most active extracts was evaluated. At non-inhibitory growth concentrations, extracts showed a strong antibiofilm capacity and a slight anti-swarming and anti-QS activities. Likewise, none of the extracts were toxic up to 2500 mg/kg. For all bacteria tested (Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and Staphylococcus aureus), HE and CE of coriander were the most active extracts for inhibiting the formation and the metabolic activity of biofilm, especially for S. aureus. The anti-staphylococcal biofilm activity was confirmed by fluorescence and scanning electron microscopy. Extract-coated polystyrene surfaces decreased bacterial adhesion and subsequent biofilm formation, even after washing. A total of 11 and 14 chemical compounds were identified from the HE and CE, respectively, being oleic acid the main compound in both extracts. Particularly, the strong inhibitory activity of coriander HE against S. aureus biofilms is emphasizing. These results suggest the possible application of these extracts either as an antibiofilm agent or by generating anti-adherent surfaces in the food industry and in the clinical area.

The aim of this study was to evaluate the structural and vibrational properties and biological activity of 2-chloroethyl(methylsulfonyl)methanesulfonate, CH3SO2CH2SO2OCH2CH2Cl (clomesone). The solid-state molecular structure has been isolated and characterized using experimental (X-ray diffraction) and theoretical (DFT method) methodologies. The molecules are packed through C-H⋯O bifurcated interactions and Cl⋯Cl interactions. The experimental investigations are supplemented by quantum chemical calculations and Hirshfeld surface calculations. Furthermore, the infrared and Raman spectra of the solid phase have been obtained, and the observed bands are assigned to the vibrational normal modes. This study is completed using the atoms-in-molecules (AIM) theory and natural bond orbital (NBO) analysis. Finally, we studied the function of clomesone in biofilm formation and investigated a methanesulfonate complex with respect to QS activity., Centro de Química Inorgánica, Instituto de Física La Plata

In recent years, goat's milk has shown a number of advantages over the milk from other ruminant species. Some milk substances can alter the milk quality and also present potential carcinogenic activity. In this work, chemical composition and mutagenic compounds were determined using Ames test on goat milk from different geographical locations of northern Argentina. In Tucumán, two extensive farms were analyzed, one of them near to soybean culture, La Perla Farm, where the goat́s milk showed 788 ± 33 colonies/plate and the Sunchales Farm, which milk contained 655 ± 51 colonies/plate. The third is a public organization with semi-extensive INTA Farm, where Ames test indicated 210 ± 28 colonies/plate. A goat probiotic mixture (GPM): Lactobacillus reuteri DDL19, Lactobacillus alimentarius DDL48, Bifidobacterium bifidum DDBA and Enterococcus faecium DDE39 was orally administered as a treatment to diminish toxic substances. Ames test after a 25-days treatment with probiotics bacteria, showed 455 ± 47; 300 ± 33, and 102 ± 36 colonies/plate from goat milk obtained from La Perla, Sunchales and INTA farms, respectively. After a 50-days treatment, the Ames test detected 289 ± 23, 126 ± 26, and 60 ± 5 colonies/plate, in goat milk from La Perla, Sunchales and INTA farms, respectively. Moreover, the probiotic administration did not modify the milk physical-chemical composition; with the exception of fatty acid. The diminution of the mutagen capacity of milk could respond to observed modification on fat content. These results reinforce previous results about adsorption of mutagens by the strains contained in the GPM and define the first scientific results on this topic. The GPM, added to goat diet, did not influence protein and nonfat solids contents, acidity and density values, but allowed the obtaining of milk characterized by improving the concentration of beneficial compounds. The study supports the use of probiotics to enhance the quality of goat products. Fil: Méndez Utz, Virginia Emilce. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Apas, Ana Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina Fil: Díaz, Myriam Anabel. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Gonzalez, Silvia Nelina. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

In this work, we intended to inhibit the biofilm synthesis and the metabolism of Gram-positive and Gram-negative bacteria using two highly available wastes (stem and marc) obtained after the manufacturing of Torrontes wine at Cafayate, Argentina. Wine wastes contain a significant amount of bioactive compounds, mainly phenolic compounds, which makes them a potential source of compounds with beneficial properties to human health, as they could inhibit the virulence of pathogenic bacteria or protect the tissue against oxidative stress. Marc and stem extracts of Torrontes wine were evaluated for their ability to inhibit the metabolism and biofilm production of Pseudomonas aeruginosa and Staphylococcus aureus strains. The phytochemical composition and antioxidant activity of these extracts were also determined. The methanol and ethyl acetate extracts, which contained the highest amount of total polyphenolic, exhibited the highest scavenging capacity of ABTS and nitric oxide and the strongest Fe3+ reducing power and exhibited the highest level of inhibition of the biofilm formation and of the metabolic activity in bacterial biofilm. We also noticed a positive correlation between phenolic compounds content, the antioxidant activity, and the anti-biofilm capacity of the winemaking wastes. These results display the potentiality of wine wastes to prevent or reduce the formation of biofilm. Moreover, their abundance makes them an attractive and affordable source of antibiofilm and antioxidant agents.

The reaction in alkaline aqueous solution between sulfamethoxazole (SMX) and manganese (II) chloride produces colorless crystals with formula [Mn(H2O)6]0.5[Mn(SMX)3], which was characterized by UV-Vis, IR and Raman spectroscopy and thermal analysis. The crystal structure of [Mn(H2O)6]0.5[Mn(SMX)3] complex has been solved by X-ray diffraction methods. It crystallizes in the cubic Pa-3 space group with a = 19.5476(1) Å, and Z = 8 molecules per unit cell. [Mn(SMX)3]- complex is at a crystallographic special position of C3 symmetry with the Mn(II) ion cis-coordinated to three equivalent sulfamethoxazole molecules acting as bidentate ligands in a propeller-like conformation. [Mn(H2O)6]2+ hydrate ion is at crystal special position of S6 symmetry with the metal in an almost perfect octahedral coordination with six water molecules. At 100 μg/mL Mn(H2O)6]0.5[Mn(SMX)3] and SMX, inhibited the Staphylococcus aureus biofilm formation by 92% and 54%, respectively. However, at the same concentration Mn(H2O)6]0.5[Mn(SMX)3] and SMX inhibited the planktonic bacterial growth by 52% and 81%, respectively. The Mn(II) complex inhibited the biofilm formation in values higher than 35% at the concentration 0.5 μg/mL. These results suggest that the metal complex [Mn(H2O)6]0.5[Mn(SMX)3] is a good candidate for the development of new antimicrobial agent acting in part as bactericidal but mainly as antipathogenic agent. Fil: Di Santo, Alfredo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Física; Argentina Fil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina Fil: Pomiro, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Piro, Oscar Enrique. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Echeverría, Gustavo Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Luciardi, María Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Carbonio, Raul Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Ben Altabef, Aída. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Inorgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina

Quorum sensing (QS) is a cell-to-cell signaling communication system that controls the virulence behavior of a broad spectrum of bacterial pathogens, participating also in the development of biofilms, responsible of the antibiotic ineffectiveness in many infections. Therefore, QS system is an attractive target for antimicrobial therapy. In this study, we compare the effect of seven structurally related coumarins against bacterial growth, biofilm formation and elastase activity of Pseudomonas aeruginosa. In addition, the anti-pathogenic capacity of the seven coumarins was evaluated on the wild type and the biosensor strain of Chromobacterium violaceum. The comparative study of coumarins showed that molecules with hydroxyl groups on the aromatic ring displayed higher activity on the inhibition of biofilm formation of P. aeruginosa over coumarins with substituents in positions 3 and 4 or without the double 3,4-bond. These 3 or 4-hydroxylated positions caused a decrease in the anti-biofilm activity obtained for coumarin. However, the hydroxyl group in position 3 of the pyrone ring was important for the inhibition of C. violaceum QS and elastolytic activity of P. aeruginosa. The effects observed were active independently of any effect on growth. According to our results, coumarin and its hydroxylated derivatives represent an interesting group of compounds to use as anti-virulence agents against the human pathogen P. aeruginosa. Fil: D'almeida, Romina Elisa. Universidad Nacional de Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria.; Argentina Fil: Molina, Rocío Daniela Inés. Universidad Nacional de Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria.; Argentina Fil: Viola, Carolina Maria. Universidad Nacional de Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria.; Argentina Fil: Luciardi, María Constanza. Universidad Nacional de Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria.; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Nieto Peñalver, Carlos Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Instituto de Biotecnología Farmaceutica y Alimentaria.; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

Different peppers fermentations (Capsicum annum, grossum variety) were assayed: spontaneous, native microflora sup- plemented individually with Lactobacillus plantarum N8, Leuconostoc mesentereroides L. or Pediococcus pentosaceus 12p and by pure or combined cultures of these lactic acid bacteria (LAB). In order to eliminate the native flora, different kinds of heat treatment were assayed. The treatment selected was heating in autoclaved after research 3/4 atmosphere and to turn off. Fermentations were carried out at 22°C and 30°C and the culture media contained 2% or 0.2% glucose and 4% NaCl. Sugar consumption, pH reduction and acid production were higher at 30°C than at 22°C. At both tem- peratures, spontaneous fermentation showed a slower rate reduction in pH than inoculated samples. Diminution in pH in presence of 2% glucose was faster than at 0.2%, but minimum pH was in both case lower than 3.0. Maximum growth was reached between 2 and 5 days of fermentation in all the samples assayed. After 30 days of incubation in presence of 2% glucose the survival of LAB was nearly 5 log ufc/ml. The survival was higher at the lower temperature assayed for both glucose concentrations. Organoleptic properties of peppers fermented with a mixed culture of Leuconostoc mes- enteroides and Pediococcus pentosaceus were found best by a human panel. This sample has a relation lactic acid/acetic acid of nearly 3 in the conditions assayed. Fil: Alberto, Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; Argentina Fil: Perera, María Francisca. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; Argentina

The current trend of increasing air, water, and soil pollution is, in part, due to inadequate management of municipal solid waste (MSW). The relationship between public health and the collection, storage and improper disposal of solid waste has encouraged several studies and the results were attributed to the spread of over twenty human and animal diseases due to this interrelationship. The term single cell protein (SCP) refers to microbial biomass used as a dietary additive. It has high nutritional value because of its high content of vitamins, lipids, and proteins of biological quality (the presence of all essential amino acids) (Lal, 2005). The aim of this work was to design a culture media for microbiological assays and to produce SCP for animal feeding, using nutrients contained in organic waste. In order to compare the effectiveness of food waste (FW) and LAPTg media, different strains of Lactobacillus, Enterococcus, Staphylococcus, Shigella, Salmonella, Saccharomyces and Schizosaccharomyces were studied. In all cases, the growth obtained from FW and LAPTg culture media were not significantly different (p > 0.05). In addition, the growth of Saccharomyces cerevisiae was studied in order to produce SCP for animal feeding. Comparative experiments involving molasses broth, FW broth, and basal broth were carried out. The biomass yield calculated at 24 h from FW broth was 13% lower than from molasses broth. The FW broth provided a significantly lower biomass yield; however, it can be very useful in areas where molasses are not available. FW broth can be elaborated at low cost, in any populated region of the world because its ingredients are wastes generated by humans. It has great versatility, allowing the development of a wide variety of microorganisms, both Gram negative and Gram positive bacteria as well as yeasts. The production of safe protein additives, with high biological quality and low cost, is necessary due to the increasing global demand for food for humans and animals. Fil: Chalon, Miriam Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentina Fil: Terán, Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Oliszewky, Ruben. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentina Fil: Gonzalez, Silvia Nelina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentina

Zuccagnia punctata Cav. (Fabaceae), a native plant from Argentina has been used traditionally as medicinal species. The aim of the study was to validate the antibiotic and anti-inflammatory potential of Z. punctata organic extract (ZpE) and the major compounds; 2´,4´-dihydroxy-3´-methoxychalcone (DHMC), 2´,4´-dihydroxychalcone (DHC), 7-hydroxyflavanone (7-HF) and 3,7-dihydroxyflavone (DHF); using an in vitro model. The antibiotic activity was determined using a broth microdilution method and the minimum inhibitory concentration (MIC) was determined. The extract and the isolation compounds affect the normal growth of all assayed Staphylococcus aureus strains. The MIC values for ZpE and isolated compounds were between 125 and 500μg/mL and between 25 and 400μg/mL, respectively, against all assayed strains. The inhibitory effect of extract and isolated compounds on biofilm formation and on pro-inflammatory enzymes (sPLA2, COX-2, LOX) was analyzed. The compound DHC was the most active on sPLA2 while DHF and DHMC showed the highest activity on LOX. Both the extract and pure compounds except DHMC were active against COX-2. It can be concluded that the phytocomplex and the pure compounds possessed antibiotic and anti-inflammatory activities under the conditions tested, and could be a good alternative therapy for infective and inflammatory processes. Fil: Nuño, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Alberto, Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Zampini, Iris Catiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina

Pseudomonas aeruginosa produces biofilm and several virulence factors coordinated by quorum sensing (QS) in food. The interruption of QS is a target to control the bacterial virulence. Chemical preservatives used to control biofilm give rise to several food safety problems. For this reason, essential oils (EOs), generally recognized as safe products, are a hopeful alternative. The aim of this work was to determine the chemical composition of mandarin EOs obtained by cold-pressing (EOP) and cold-pressing followed by steam distillation (EOPD) and their antipathogenic properties against P. aeruginosa. Both EOs contained the highest quantities of monoterpene hydrocarbons, mainly limonene, followed by γ-terpinene, myrcene and α-pinene. Although the EOs were not able to inhibit the bacterial growth at 4 mg/mL, EOP and EOPD significantly inhibited the P. aeruginosa biofilm formation at 0.1 mg/mL. In addition to the EOs inhibited biofilm cell viability (41%), AHL production (33%) and resulted in higher than 75% reduction in elastase enzyme activity. In conclusion, Citrus reticulata EOs are suitable alternatives to chemical additives for general use in the food industry. Fil: Luciardi, María Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Blazquez, María Amparo. Universidad de Valencia; España Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina

Increasing chronic bacterial infections create an urgent need for new antimicrobial agents or strategies for their control. Targetingvirulence is one of the alternative approaches to find new medicines to treat persistent infections due to bacteria with biofilmphenotypewhich are more resistant to antibiotics than their planktonic counterparts having an extreme capacity for evading the host defences. A bioguided study of sixteen extracts from flowers and leaves of four subtropical Convolvulaceae species provided evidence of the occurrence of antipathogenic natural products active against Gram positive and negative bacteria.Particularly, volatile metabolites from Merremia dissecta creeper, a food and medicinal plant, were able to interfere with the Pseudomonas aeruginosa quorum sensing system by a strong decrease of N-acyl homoserine lactone (AHL) biosynthesis (63?75%), which attenuated the virulence factor expression like biofilm (55%) and elastase activity (up to 27%), key factors thatenable the colonization and dissemination of the infection in the host. Control of the P. aeruginosa biofilm and the QS process by phytochemicals, such as (+) spathulenol, isolated from a bioactive extract of M. dissecta leaves would be a good strategy for the development of new and effective antipathogenic drugs. Fil: Luciardi, María Constanza. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina Fil: Pérez Hernández, María Victoria. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Muruaga, Nora. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina

BACKGROUND: Lactobacillus hilgardii, a wine lactic acid bacterium, is able to use arginine, through the arginine deiminase pathway with the formation of citrulline, a precursor of the carcinogen ethyl carbamate. The influence of different Argentine wine varieties (Merlot, Cabernet Sauvignon and Malbec), on bacterial growth and arginine metabolism was examined. Furthermore, the effect of different components normally present in wines on the enzyme activities of the arginine deiminase system was determined. RESULTS: Malbec wine under all conditions assayed (33, 50 and 100% supplemented wine:basal media) showed higher arginine consumption and citrulline production than the other wines, as well as the highest bacterial growth and survival of Lactobacillus hilgardii X1B. Glucose and L-malic inhibited both arginine deiminase enzymes while fructose and citric acid only inhibited arginine deiminase. The red wines assayed in this study had different composition, and this is an explanation for the different behavior of the bacterium. CONCLUSION: The highest citrulline production in Malbec wine could be correlated with its lower concentrations of glucose, fructose, citric and phenolic acid than the other wines. Therefore, a wine with lower concentration of these sugars and acids could be dangerous due to the formation of ethyl carbamate precursors. Copyright © 2012 Society of Chemical Industry

Four fusicoccane-type diterpenoids (1−4), including the new 1 and 2; four pinguisane-type sesquiterpenoids (5−8); and two aromadendrane-type sesquiterpenoids (9 and 10) were isolated from an Argentine collection of the endemic liverwort Porella chilensis. The biofilm formation of the human pathogen Pseudomonas aeruginosa was inhibited by compounds 3 (53 and 47%), 9 (45 and 41%), and 10 (48 and 37%) at 50 and 5 μg/mL, respectively. Compounds 3, 9, and 10 also produced a slight decrease in bacterial growth and interfere with the process of quorum sensing at the same doses. Fil: Gilabert Valero, José Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Ramos Vernieri, Alberto Nicolás. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Schiavone, Maria Magdalena. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina

Seven new prenylated acylphloroglucinols, yungensins A-G, were isolated from the diethyl ether extract of the scaly rhizomes and roots of an Argentine collection of the fern Elaphoglossum yungense. All the compounds contained a geranyl group attached to the filicinic acid-type residue. The diethyl ether extract and yungensins A-F displayed antibacterial effects against Staphylococcus aureus and Pseudomonas aeruginosa with MICs ranging from 10 to 200 μg/mL. All tested acylphloroglucinols, except for yungensin D, caused bacteriolysis of S. aureus at MBC or higher doses (50-200 μg/mL). At 10 μg/mL, the ether extract as well as yungensins A, B, and D-F altered the biofilm production in both microoganisms. Fil: Socolsky, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Tokoshima Bunri University; Japón Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Asakawa, Yoshinori. Tokoshima Bunri University; Japón Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

Acanthospermal B (AcB), the major sesquiterpene lactone (SL) of Acanthospermum hispidum, an herb widely spread in Argentina, is a selective antibacterial agent against Enterococcus faecalis and Staphylococcus aureus, but inactive on Gram-negative and Lactobacillus. Methicillin-resistant Staphylococcus aureus (MRSA) is one of the main microorganisms involved in human chronic infection. A balb\c mouse skin infection model was developed to reproduce the lesions caused by acute and chronic infections produced by MRSA. After determination of the maximum concentration of AcB unable to produce tissular injury after intradermal injection, the anti-MRSA effect of AcB was evaluated on skin, liver and spleen tissues of infected mice. AcB, at doses of 2.5 mg/kg, produced a ten times decrease of MRSA growth in skin infection. In addition, the same dose prevented the dissemination to liver and/or spleen. AcB also displayed a bacteriostatic effect, in vitro, on MRSA cultures at 50 µg/mL that seems to be caused by partial denaturation of total bacterial DNA and/or inhibition of the PCR reaction in not denaturized DNA. Finally, total MRSA cell wall lysis occurred at a concentration of 100 µg/mL of AcB after 2 h of exposure. Copyright © 2010 John Wiley & Sons, Ltd.

Sugar production from sugarcane generates residual products, currently, many of which are waste products. At the same time, introduction of probiotic bacteria to food animals needs an economical production medium. Fermentation of sugarcane blunting, an industrial residue, inoculated with ruminant probiotic bacteria was investigated. Fermentation was carried out using native flora (NF) alone, NF plus a goat probiotic lactic acid bacterium (LAB), and NF plus goat probiotic co-inoculated with two LAB isolated from sugarcane. Survival of microorganisms and metabolite produce were monitored. In the inoculated samples, pH was lower, dry matter was >30%, and Enterobacteriaceae and fungus decreased when compared to natural fermentation. The LAB inoculated grew and multiplied during fermentation. All beneficial changes were more quickly in the co-inoculated samples. The results presented indicate that sugarcane blunting can be used as a medium for introduction of ruminant probiotic bacteria. Fermentation of blunting can prolong shelf life and increase microbiological safety.

This article aims to study putrescine production in Lactobacillus hilgardii strain X1B, an agmatine degrader isolated from wine, and to compare it with three other different species, previously reported as putrescine producers from agmatine: Pseudomonas aeruginosa PAO1, Enterococcus faecalis ATCC11700 and Bacillus cereus CECT 148T. The effect of different biogenic amines, organic acids, cofactors, amino acids and sugars on putrescine production was evaluated. In some cases, a similar effect was found in all the strains studied but the magnitude differed. Arginine, glucose and fructose showed an inhibitory effect, whereas the presence of agmatine induced the production of putrescine in all microorganisms. In other cases, the effect differed between P. aeruginosa PAO1 and the other microorganisms. Histamine and tyramine poorly influenced the utilization of agmatine, although a small increase in putrescine production was observed in P. aeruginosa PAO1. Succinate, spermidine and spermine also led to an increase in putrescine production in P. aeruginosa PAO1, whereas the succinate had no effect in the other microorganisms. Spermine and spermidine always produced a diminution in agmatine deamination. In this work, we have also demonstrated that pyridoxal 5-phosphate, Mg2+ and Mn2+ had no effect on putrescine production from agmatine. Results presented in this paper indicate differences in regulation mechanisms of agmatine deiminase pathway among P. aeruginosa PAO1 and L. hilgardii X1B, E. faecalis ATCC11700 and B. cereus CECT 148T. These results are significant from two points of view, first food quality, and second the toxicological and microbiological aspects. It should be taken into account that putrescine, whose origin is still controversial, is quantitatively the main biogenic amine found in food. Fil: Landete, J. M.. Universidad de Valencia; España Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Pardo, I.. Universidad de Valencia; España Fil: Manca, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Ferrer, S.. Universidad de Valencia; España

The aim of this article was to analyze the ability of wine Lactobacillus plantarum strains to form tyramine. Preliminary identification of L. plantarum strains was performed by amplification of the recA gene. Primers pREV and PlanF, ParaF and PentF were used respectively as reverse and forward primers in the polymerase chain reaction tests as previously reported. Furthermore, the gene encoding for the tyrosine decarboxylase (TDC) was partially cloned from one strain identified as L. plantarum. The strain was further analyzed by 16S rDNA sequence and confirmed as belonging to L. plantarum species. The tyrosine decarboxylase activity was investigated and tyramine was determined by the high-performance liquid chromatography method. Moreover, a negative effect of sugars such as glucose and fructose and L-malic acid on tyrosine decarboxylase activity was observed. The results suggest that, occasionally, L. plantarum is able to produce tyramine in wine and this ability is apparently confined only to L. plantarum strains harboring the tdc gene. Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Fiocco, D.. Foggia University; Italia Fil: Manca, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Pardo, I.. Universidad de Valencia; España Fil: Spano, G.. Foggia University; Italia

Context: It is necessary to advance the field of alternative treatments for chronic wounds that are financially accessible to the least economically developed countries. Previously we demonstrated that topical applications of Lactobacillus plantarum culture supernatants (LAPS) on human-infected chronic wounds reduce the pathogenic bioburden, the amount of necrotic tissue, and the wound area, as well as promote debridement, granulation tissue, and wound healing. Objective: To study LAPS chemically and biologically and to find potential molecules responsible for its pro-healing and anti-pathogenic properties in chronic wounds. Materials and methods: (1) Chemical analysis: extracts were subjected to a column chromatography and the fractions obtained were studied by GCMS. (2) Quantification: dl-lactic acid (commercial kit), phenolic compounds (Folin?Ciocalteu), H2O2 (micro-titration), and cations (flame photometry). (3) Biological analysis: autoinducers type 2 (AI-2) (Vibrio harveyi BB170 bioassay), DNAase activity (Agar DNAase), and Pseudomonas aeruginosa biofilm inhibition (crystal violet technique). Results: According to its biological activity, the most significant molecules found by GCMS were the following: antimicrobials (mevalonolactone, 5-methyl-hydantoine, benzoic acid, etc.); surfactants (di-palmitin, distearin, and 1,5-monolinolein); anesthetics (barbituric acid derivatives), and AI-2 precursors (4,5-dihydroxy-2,3-pentanedione and 2-methyl-2,3,3,4-tetrahydroxytetrahydrofurane). Concentrations measured (µg/mL): dl-lactic acid (11.71 ± 1.53) and H2O2 (36 ± 2.0); phenolic compounds (485.2 ± 15.20); sodium (370 ± 17); potassium 920 ± 24); calcium (20 ± 4); and magnesium (15 ± 3). DNAase from LAPS had activity on genomic DNA from PMNs and P. aeruginosa. Discussion and conclusion: The molecules and biological activities found in LAPS could explain the observed effects in human chronic wounds. Fil: Ramos, Alberto. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología. Cátedra de Inmunología; Argentina Fil: Sesto Cabral, María Eugenia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Arrighi, Carlos Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Arroyo Aguilar, Abel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Valdez, Juan C.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología. Cátedra de Inmunología; Argentina

The effect of a mixture of potentially probiotic bacteria (MPPB; Lactobacillus reuteri DDL 19; Lactobacillus alimentarius DDL 48; Enterococcus faecium DDE 39; and Bifidobacterium bifidum strains) on milk fatty acid (FA) profile with emphasis on cis9, trans11 conjugated linoleic acid (CLA) in the middle stage of goat lactation was determined. In addition, the effects of MPPB feeding on FA profile in intestinal content and intestinal morphology in weaned goats were analyzed. The probiotic supplement was able to modify FA composition of milk and intestinal content. The unsaturated FA concentrations in milk (g of FA/L of milk)e increased from 4.49 to 7.86 for oleic (18:1), from 0.70 to 1.39 for linoleic (18:2), from 0.063 to 0.187 for linolenic (18:3) acids, and from 0.093 to 0.232 for CLA. The atherogenicity index diminished 2-fold after MPPB ingestion. In the intestinal content of the weaned goats, no significant difference in saturated FAs compared to the control was observed. However, oleic acid, linolenic acid, CLA, and docosahexaenoic acid (DHA) concentrations increased by 81, 23, 344, and 74%, respectively, after probiotic consumption. The ruminal production of CLA was increased by the MPPB. However, bacterial strains of MPPB were unable to produce CLA in culture media.By histological techniques, it was observed that the treated group had intestinal more conserved morphological structures than the control group. The results obtained in this study indicate that the MPPB administration in lactating and weaned goats allows for the production of milk with improved concentrations of beneficial compounds, and also produces a protective effect in goat intestine. The results obtained in this study reinforce the strategy of probiotics application to enhance goat health with the production of milk with higher concentration of polyunsaturated FA. Fil: Apas, Ana Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; Argentina Fil: Colombo, Silvia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Gonzalez, Silvia Nelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; Argentina

The aim of this work was to study the effects of ethanol on cell growth and arginine and citrulline metabolism in two heterofermentative lactic acid bacteria from wine, and to determine their possible association with the formation of ethyl carbamate (EC), a carcinogenic compound. Lactobacillus hilgardii X1B is able to utilize arginine and citrulline, while Oenococcus oeni m can only use citrulline, a precursor of EC. Growth of both microorganisms was partially inhibited by 10 and 15% (v/v) ethanol. Specific arginine consumption by L. hilgardii increased when the pH value diminished from 6.5 to 3.8, but was not affected by an increasing ethanol concentration. However, the ethanol concentration affected the specific citrulline consumption of both microorganisms. Arginine metabolism by L. hilgardii X1B increased the amount of citrulline, thus allowing production of EC in the medium. Citrulline utilization by both microorganisms, at all pH values studied, indirectly inhibited the formation of EC; indeed, one of the precursors had practically disappeared after 48 h of incubation. Due to its ability to form precursors, L. hilgardii X1B has the potential to contribute to EC formation, whereas citrulline utilization by O. oeni m in the presence of ethanol may contribute to diminishing the formation of EC. Rapid degradation of citrulline in the presence of ethanol by O. oeni m is important from a toxicological point of view, because it is important to keep the EC levels as low as possible. Fil: Arena, Mario Eduardo. 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; Argentina 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; Argentina

Aspergillus is a promising source of bioactive secondary metabolites. The addition of insect-derived material in the broth culture could trigger the biosynthesis of insecticidal and antimicrobial compounds by entomopathogenic fungus (EF). Insects inhabit diverse niches and interact with various bacteria, for this reason, when a fungus kills an insect should inhibit the insect?s gut bacteria to prevent the insect consumption by bacteria. According with this hypothesis, the EF is able to produce substances that inhibit bacteria growth or bacteria virulence strategies. In the present, investigation is demonstrated that the addition of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) components (2 % w/v) in a culture of saprophytic fungus Aspergillus parasiticus MOR 3 induces the production of a novel compound present inside mycelium 2-(4-bromophenyl)-2-oxoethyl benzoate, that is reported here for the first time as a natural product of A. parasiticus. In addition, increased significantly the fungal extracellular production of undecyl 4-fluorobenzoate. The mycelium extract (ME) at 250 μg per g of diet on adult population of T. castaneum produced an alteration of the feeding behavior of coleopteran insects (Repellency index = +30). The fraction derived from ME (Fr2) that contained the organobromine compound, 2-(4-bromophenyl)-2-oxoethyl benzoate had the highest inhibition of the Pseudomonas aeruginosa virulence factors like elastase enzyme (49 %) at 5 μg/ml and biofilm formation (43 %) at 100 μg/ml. The results suggest that the extract from mycelium of a non-aflatoxigenic A. parasiticus MOR 3 strain is a potential candidate as food coleopteran repellent as well as an anti-virulence strategy of P. aeruginosa. Fil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Marcinkevicius, Karenina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina Fil: Luciardi, María Constanza. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Rodriguez, German. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina

Aims: The aim of this work was to demonstrate that strains of Lactobacillus may be able to produce putrescine and agmatine from one of the major amino acids present in fruit juices and wine, arginine, and from amino acid-derived ornithine. Methods and Results: Biogenic amines were determined by HPLC. Their production in the culture medium was similar under both microaerophilic and anaerobic conditions. The presence of Mn 2+ had a minimal influence on the results, whereas the addition of pyridoxal phosphate increased amine production 10-fold. Lactobacillus hilgardii X1B, isolated from wine, was able to degrade arginine by two pathways: arginine deiminase and arginine decarboxylase. The isolate was able to produce putrescine from ornithine and from agmatine. Lactobacillus plantarum strains N4 and N8, isolated from orange, utilized arginine via the arginine deiminase system. Only the N4 strain was able to produce putrescine from ornithine. Conclusions: It has been demonstrated that Lact. hilgardii X1B is able to produce the most important biogenic amine found in wine, putrescine, and also agmatine from arginine and ornithine, and that Lactobacillus plantarum, considered to be an innocuous spoilage microorganism in fruit juices, is able to produce amines. Significance and Impact of the Study: The results have significance in relation to food poisoning caused by beverages that have been contaminated with biogenic amines.

The mutagen binding ability of the goat probiotics (Lactobacillus reuteri DDL 19, Lactobacillus alimentarius DDL 48, Enterococcus faecium DDE 39, and Bifidobacterium bifidum DDBA) was evaluated. The oral administration of these probiotics reduced fecal mutagens and intestinal cancer markers in goats. Secondly, the effects of probiotics against the mutagenesis induced by sodium azide (SA), and Benzopyrene (B[α]P) by performing the modified Ames test using Salmonella typhimurium TA 100 was investigated. The capacity to bind benzopyrene and the stability of the bacterial–mutagen complex was analyzed by HPLC. The dismutagenic potential against both mutagens was proportional to probiotic concentration. Results showed that probiotic antimutagenic capacity against SA was ranging from 13 to 78%. The mixture of four goat probiotics (MGP) displayed higher antimutagenic activity against SA than any individual strains at the same cell concentration. This study shows that the highest diminution of mutagenicity in presence of B[α]P (74%) was observed in presence of MGP. The antimutagenic activity of nearly all the individual probiotic and the MGP were in concordance with the B[α]P binding determined by HPLC. According to our results, the B[α]P binding to probiotic was irreversible still after being washed with DMSO solution. The stability of the toxic compounds-bacterial cell binding is a key consideration when probiotic antimutagenic property is evaluated. MGP exhibits the ability to bind and detoxify potent mutagens, and this property can be useful in supplemented foods for goats since it can lead to the removal of potent mutagens and protect and enhance ruminal health and hence food safety of consumers. Fil: Apas, Ana Lidia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman; Argentina Fil: Gonzalez, Silvia Nelina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman; Argentina Fil: Arena, Mario Eduardo. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman; Argentina

Six sesquiterpene lactones (SLs) of the goyazensolide and isogoyazensolide-type isolated from the Argentine herb Centratherum punctatum were evaluated on their ability to inhibit virulence factors of Pseudomonas aeruginosa ATCC 27853. Although compounds were able to completely inhibit bacterial growth at 200 µg/ml, the SLs do altered biofilm formation, elastase activity, and production of N-acyl-homoserinelactones (AHL) which are known quorum sensing autoinducers at lower concentration. Compounds 2, 3, and 5 displayed significant inhibitory effects on P. aeruginosa biofilm formation at 0.5 µg/ml being compound 3 (1.32 µM) the most potent (42%). Compounds 2,3, 4, 5, and 6, inhibited 39, 44, 42, 32 and 35% the production of AHLs at 100 µg/ml and inhibited by more than 50% the elastase activity at 0.5 µg/ml. Our results clearly indicated that sesquiterpene lactones are good candidates for the development of new antimicrobial agents acting not as bactericidal but as antipathogenic agents. Fil: Amaya, Susana del Valle. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Pereira, José A.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Borkosky, Susana Alicia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Valdéz, Juan Carlos. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina

The effect of different fermenting microorganisms on growth of a mycotoxin- producing Aspergillus nomius was assayed. Two lactic acid bacteria, Lactobacillus fermentum and Lactobacillus rhamnosus, and Saccharomyces cerevisiae, all of which are widely used in fermentation and preservation of food, were assayed on their fungus inhibitory properties. Assays were carried out by simultaneous inoculation of one of the possible inhibiting microorganisms and the fungus or subsequent inoculation of one of the microorganisms followed by the fungus. All three microorganisms assayed showed growth inhibition of the mycotoxin-producing Aspergillus strain. L. rhamnosus O236, isolated from sheep milk and selected for its technological properties, showed highest fungal inhibition of the microorganisms assayed. The use of antifungal LAB with excellent technological properties rather than chemical preservatives would enable the food industry to produce organic food without addition of chemical substances. Fil: Muñoz, R.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Silva, J.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Gonzalez, Silvia Nelina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina

The application of potentially beneficial microorganisms to increase host defense is a new trend to increase health benefits. In this paper the first specific host probiotics for goats from a mixture isolated from healthy animals (Lactobacillus reuteri DDL 19, Lactobacillus alimentarius DDL 48, Enterococcus faecium DDE 39 and Bifidobacterium bifidum DDBA) was assayed. The effect of probiotic oral administration on goats' weight, gut microbiota, as well as on the production of mutagen compounds and their indicator (putrescine), were evaluated. The probiotic supplement was able to modify microflora balance by reducing Enterobacteria like Salmonella/Shigella (1.09 and 1.21 log CFU/g feces, respectively) and increasing lactic acid bacteria and Bifidobacteria (1.67 and 2.34 log CFU/g feces, respectively). The probiotics administration was correlated with a ten time diminution of fecal putrescine (cancer and bacterial disease marker) and a decrease of 60% mutagen fecal concentration, indicating the protective effect of the treatment. Additionally, a significant increase in ruminant weight was observed after probiotic administration. These results are encouraging towards the use of probiotic mixtures as functional food for goats.