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Se presentan los primeros resultados de la observación con filtro de banda angosta ([NII], 6584 A) de una muestra de nebulosas planetarias australes. Las observaciones se están realizando desde la Estación Astrofísica de Bosque Alegre. Los aspectos inherentes de la observación serán tratados en detalle. Fil: Vena Valdarenas, Román Rodrigo. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina Fil: Schmidt, Eduardo Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina Fil: Volpe, M. G.. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina Fil: Weidmann, Walter Alfredo. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Mudrik, A.. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina

In this study two algal polysaccharides, alginate and agar, chitosan from chitin, and one fruit extracted polysaccharide, pectin, have been used as binders to make solid pellets to be employed in intensive crayfish farming. We examined the performance of the pellets in water and their effect on crayfish growth. The kinetics of water absorption and solute leaching of the pellets were measured for up to 24 h. Recovered liquid was analyzed for the release of particles in water by a Low Angle Laser Light Scattering Technique. The pellets were stable in water up to 24 h, although the water stability of pectin based pellets and chitosan based pellets was greater than other pellets. At the same time, crayfish feeding response to each pellet type was monitored in growth experiments by testing diets containing similar concentrations of nutrients (proteins, lipids and carbohydrates) mixed with each of the different polysaccharides. The presence of polysaccharides positively affected crayfish growth. Indeed, animals fed these pellets showed a higher percentage growth when compared to control animals. The simple methodology used for making pellets, and the encouraging results obtained in this study, could be considered suitable parameters for people interested in crayfish farming under intensive conditions. [Keywords.-- aquaculture; Cherax albidus; food pellets; polysaccharides; rheological characteristics].

The role of environmental factors in influencing health status is well documented. Heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, dioxins, pesticides, ultrafine particles, produced by human activities put a strain on the body’s entire defense system. Therefore, together with public health measures, evidence-based individual resilience measures are necessary to mitigate cancer risk under environmental stress and to prevent reproductive dysfunction and non-communicable diseases; this is especially relevant for workers occupationally exposed to pollutants and/or populations residing in highly polluted areas. The Mediterranean diet is characterized by a high intake of fruits and vegetables rich in flavonoids, that can promote the elimination of pollutants in tissues and fluids and/or mitigate their effects through different mechanisms. In this review, we collected evidence from pre-clinical and clinical studies showing that the impairment of male fertility and gonadal development, as well as cancers of reproductive system, due to the exposure of organic and inorganic pollutants, may be counteracted by flavonoids.

Grape harvesting generates a high amount of wastes, mostly leaves, which represent an economic and ecological problem for farmers. New products can be generated through these wastes, giving environmental, social, and economic advantages while also meeting the industry demand for novel natural ingredients. In this study, aqueous leaf-extracts from two cultivars of Vitis vinifera Aglianico (Agl) and Greco di Tufo (Gre) were produced by microwave-assisted extraction (MAE) and evaluated in composition by ATR- FTIR and HPLC to identify the main phenolic compounds, especially quercetin and kaempferol. The results showed that leaves extracts confirm to be a potential source of phenolic compounds. Dry extracts, although highly functional, show critical handling characteristics, being sticky and unstable in normal post-processing conditions. A stable and easy handling microparticulate ingredient was produced by spray drying containing the most phenolic-rich obtained extract (AGL-28). The microparticle powder form based on pectin/maltodextrin matrix was produced with high process efficiency. The microstructures were able to confer functional and chemical stability to the extract while also showing good technological characteristics (high water dissolution rate and flow properties), transforming the extract into a handling ingredient able to meet new industrial uses.

In the last decades, resistant microbial infection rate has dramatically increased, especially infections due to biofilm-producing strains that require increasingly complex treatments and are responsible for the increased mortality percentages compared with other infectious diseases. Considering that biofilms represent a key factor for a wide range of chronic infections with high drug tolerance, the treatment of biofilm-causing bacterial infections represents a great challenge for the future. Among new alternative strategies to conventional antimicrobial agents, the scientific interest has shifted to the study of biologically active compounds from plant-related extracts with known antimicrobial properties, in order to also evaluate their antibiofilm activity. In this regard, the aim of this study has been to assess the antibiofilm activity of polyphenolic extracts from myrtle leaf and pomegranate peel against oral pathogens of dental plaque, an excellent polymicrobial biofilm model. In particular, the in vitro antibiofilm properties of myrtle and pomegranate extracts, also in binary combination, were highlighted. In addition to inhibiting the biofilm formation, the tested polyphenolic extracts have been proven to destroy both preformed single-species and multispecies biofilms formed by Streptococcus mutans, Streptococcus oralis, Streptococcus mitis, and Rothia dentocariosa oral isolates, suggesting that the new natural sources are rich in promising compounds able to counteract biofilm-related infections.

The increasing incidence rate of oral diseases, the wide spread of antimicrobial resistance, and the adverse effects of conventional antibiotics mean alternative prevention and treatment options are needed to counteract oral pathogens. In this regard, our study aims to evaluate the antibacterial activity of polyphenolic extracts prepared from acacia honey, myrtle leaves, and pomegranate peel against cariogenic bacteria, such as Streptococcus mutans and Rothia dentocariosa. The chemical-physical parameters of acacia honey and the RP-HPLC polyphenolic profile of pomegranate peel extract have been previously described in our studies, while the characterization of myrtle extract, performed by HPLC analysis, is reported here. All the extracts were used singly and in binary combinations to highlight any synergistic effects. Moreover, the extracts were tested in association with amoxicillin to evaluate their ability to reduce the effective dose of this drug in vitro. The values of minimal inhibitory concentrations and minimal bactericidal concentrations have been used to quantitatively measure the antibacterial activity of the single extracts, while the fractional inhibitory concentration index has been considered as predictor of in vitro anticariogenic synergistic effects. Finally, a time-kill curve method allowed for the evaluation of the bactericidal efficacy of the combined extracts. The microbiological tests suggest that acacia honey, myrtle, and pomegranate extracts are able to inhibit the cariogenic bacteria, also with synergistic effects. This study provides useful and encouraging results for the use of natural extract combinations alone or in association with antibiotics (adjuvant therapy) as a valid alternative for the prevention and treatment of oral infectious diseases.

Algae have multiple similarities with fungi, with both belonging to the Thallophyte, a polyphyletic group of non-mobile organisms grouped together on the basis of similar characteristics, but not sharing a common ancestor. The main difference between algae and fungi is noted in their metabolism. In fact, although algae have chlorophyll-bearing thalloids and are autotrophic organisms, fungi lack chlorophyll and are heterotrophic, not able to synthesize their own nutrients. However, our studies have shown that the extremophilic microalga Galderia sulphuraria (GS) can also grow very well in heterotrophic conditions like fungi. This study was carried out using several approaches such as scanning electron microscope (SEM), gas chromatography/mass spectrometry (GC/MS), and infrared spectrophotometry (ATR-FTIR). Results showed that the GS, strain ACUF 064, cultured in autotrophic (AGS) and heterotrophic (HGS) conditions, produced different biomolecules. In particular, when grown in HGS, the algae (i) was 30% larger, with an increase in carbon mass that was 20% greater than AGS, (ii) produced higher quantities of stearic acid, oleic acid, monounsaturated fatty acids (MUFAs), and ergosterol, (iii) produced lower quantities of fatty acid methyl esters (FAMEs) such as methyl palmytate, and methyl linoleate, saturated fatty acids (SFAs), and poyliunsaturated fatty acids (PUFAs). ATR-FTIR and principal component analysis (PCA) statistical analysis confirmed that the macromolecular content of HGS was significantly different from AGS. The ability to produce different macromolecules by changing the trophic conditions may represent an interesting strategy to induce microalgae to produce different biomolecules that can find applications in several fields such as food, feed, nutraceutical, or energy production.

Leaves of Vitis vinifera cv. Greco di Tufo, a precious waste made in the Campania Region (Italy), after vintage harvest, underwent reduction, lyophilization, and ultrasound-assisted maceration in ethanol. The alcoholic extract, as evidenced by a preliminary UHPLC-HR-MS analysis, showed a high metabolic complexity. Thus, the extract was fractionated, obtaining, among others, a fraction enriched in flavonol glycosides and glycuronides. Myricetin, quercetin, kaempferol, and isorhamnetin derivatives were tentatively identified based on their relative retention time and TOF-MS2 data. As the localization of saccharidic moiety in glycuronide compounds proved to be difficult due to the lack of well-established fragmentation pattern and/or the absence of characteristic key fragments, to obtain useful MS information and to eliminate matrix effect redundancies, the isolation of the most abundant extract&rsquo, s compound was achieved. HR-MS/MS spectra of the compound, quercetin-3-O-glucuronide, allowed us to thoroughly rationalize its fragmentation pattern, and to unravel the main differences between MS/MS behavior of flavonol glycosides and glycuronides. Furthermore, cytotoxicity assessment on the (poly)phenol rich fraction and the pure isolated compound was carried out using central nervous system cell lines. The chemoprotective effect of both the (poly)phenol fraction and quercetin-3-O-glucuronide was evaluated.

A novel polymeric material, a poly(methylmethacrylate) (PMMA)/ethylene-co-vinylacerate (EVA) blend, is presented. The blend shows outstanding impact behaviour, at the same level as that of commercially-available ultra-tough PMMA. Moreover, transparency is retained with a transparent-to-opaque transition at about 50°C. The authors show the behaviour of the optical transmission as a function of the temperature, and measure some physical properties of this material. An attempt is made to correlate the thermo-optical behaviour to the variation, across the transition, of fundamental parameters, such as the melting of sub-included rubber particles, the refractive indices of PMMA and EVA, and the particular morphology of the blend. The latter is very interesting, as the rubber particles, by etching techniques, have been shown to be composed of sub-included PMMA domains, leading to a so-called multiple core-shell structure.