Phenolic Acids, Phenolic Aldehydes and Furanic Derivatives in Oak Chips: American vs. French Oaks

Phenolic acids (gallic, vanillic, syringic and ellagic acids), phenolic aldehydes (vanillin, syringaldehyde,coniferaldehyde and sinapaldehyde) and furanic derivatives (furfural, 5-methylfurfural and5-hydroxymethylfurfural) were quantified in commercial American and French oak chips. Chips withdifferent sizes and toast degrees were used. Compounds were extracted directly from the wood samples inorder to determine possible differences among woods as well as toast degree. Likewise, the compounds wereextracted from a synthetic wine solution to which the chip woods had been added. The results show thatFrench wood chips are generally richer than the American ones. The total amount of phenolic compoundsincreases with toasting level, with the non-toasted chips being the poorest ones. The degree of extractionfrom the synthetic wine solution seems to be related to the shape of the chips, rather than to the wood typeor toast degree

Antibacterial potential of Urtica dioica and Lavandula angustifolia extracts against methicillin resistant Staphylococcus aureus isolated from diabetic foot ulcers

Despite the antibacterial potential of plant extracts against several bacterial infections, until now, no major studies have been published about the effect of lavender and nettle leaves against methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus (MSSA and MRSA, respectively). Thus, the authors studied their antibacterial potential against MSSA and MRSA from diabetic foot ulcers in order to find alternatives to the systematic use of antibiotics. Phenolic acids, flavonoids, flavones and flavonols were extracted from lavender and nettle leaves and characterized by HPLC-DAD/Vis. Disc diffusion assay and minimum inhibitory concentration (MIC) were used to assess their antibacterial activity. A direct association between the high content of hydroxycinnamic acids (chlorogenic acid, caffeic acid, rosmarinic acid) and flavonoids (quercetin) and decreasing bacterial growth activity was noted. The fact that lavender and nettle are rich in hydroxycinnamic acids and quercetin seems to explain the high antibacterial potential of these plant and the differences between them.The authors acknowledge the financial support provided by the FCT-Portuguese Foundation for Science and Technology (Carla Dias- SFRH/BD/90120/2012 and Alfredo Aires-SFRH/BPD/65029/2009), under the Project PEst-OE/AGR/UI4033/2014.info:eu-repo/semantics/publishedVersio

Antagonistic activities of Kefirgel and Kefirgel products against Staphylococcus aureus isolated from diabetic ulcers

Diabetic foot ulcers are often complicated by infection and among pathogens the Gram-positive Staphylococcus aureus is the most common isolated. Also concomitantly, the high prevalence of methicillin-resistant S. aureus (MRSA) was significant impact on successful treatment of infected foot ulcers. In this context, the purpose of the present study was to evaluate the antibacterial properties of Kefigel®, a natural product composed by nettle (Urtica dioica L), lavender (Lavandula angustifolia Mill) and kefir grains, which have been reported as to having antibacterial activity against several diseases. Here, antibacterial effect of Kefigel® and its components were investigated against 20 S. aureus isolates (10 MSSA and 10 MRSA) collected from several diabetic foot ulcers. To assess antibacterial activity, the disk diffusion assay method, minimum inhibitory concentration (MIC), minimal bacterial activity and effects on specific growth rate, were applied. Results showed that by diffusion method, only etanolic extracts of nettle and lavender showed antibacterial activity and their effects were mainly bacteriostatic. Compared to the antibiotic gentamicin, the nettle and lavender extracts showed an efficacy between 50 and 100% relative to the antibiotic. Generally, the MRSA isolates sowed higher inhibition halos comparing MSSA isolates. In turns, Kefigel® (40mg.mL-1) affects the specific growth rate of S. aureus isolates, since after incubation for 9h almost MSSA isolates growth were inhibited. A bactericide effect was observed only against one isolates MRSA. These findings indicate a potential use of Kefigel® as a natural product having an effective effect against Staphylococus aureus. The topical use of this product for prevention of diabetic foot ulcers infections can be useful, however further investigation will be made, namely tests with high Kefigel® concentrations and synergetic effects with antibiotics

Combination of stable isotope analysis and chemometrics to discriminate geoclimatically and temporally the virgin olive oils from three mediterranean countries

The knowledge of the isotopic composition of virgin olive oil (VOO) allows the evaluation of authenticity and geographical origin, being an important tool against fraud. This study aimed to assess if VOOs produced in three Mediterranean regions could be discriminated on the basis of multivariate statistical analysis of geoclimatic and isotopic data. A total of 138 geo-referenced VOO samples from Portugal, France and Turkey from two different cultivation years were collected. The isotopic composition (δ13C, δ2H and δ18O) of VOOs was obtained using an elemental analyzer coupled to an isotope ratio mass spectrometer (EA-IRMS). One-way analysis of variance for δ13C, δ2H and δ18O showed some significant differences either between crop years or geoclimatic conditions. Based on multiple regression analyses using meteorological and geographical parameters, a meteoric water line for olive oil from Portugal, France and Turkey, in two harvest years, were created to assess the impact of climate change on their δ2H and δ18O values. Principal component analysis and Linear Discriminant Analysis, used to sort samples according to geoclimatic origin, performed best for French and Portuguese olive oils. In light of the results, multivariate isotopic analysis of VOO samples may discriminate not only between geoclimatic regions but also among cultivation years

Multidimensional continued fractions, dynamical renormalization and KAM theory

The disadvantage of `traditional' multidimensional continued fraction algorithms is that it is not known whether they provide simultaneous rational approximations for generic vectors. Following ideas of Dani, Lagarias and Kleinbock-Margulis we describe a simple algorithm based on the dynamics of flows on the homogeneous space SL(2,Z)\SL(2,R) (the space of lattices of covolume one) that indeed yields best possible approximations to any irrational vector. The algorithm is ideally suited for a number of dynamical applications that involve small divisor problems. We explicitely construct renormalization schemes for (a) the linearization of vector fields on tori of arbitrary dimension and (b) the construction of invariant tori for Hamiltonian systems.Comment: 51 page

Effect of autochthonous starter cultures in the production of "Paio", a traditional Portugese dry-cured sausage

En los países mediterráneos, como Portugal, los embutidos curados tradicionales son muy apreciados. A menudo se siguen fabricando en pequeñas unidades de procesamiento, de acuerdo con los procedimientos tradicionales. Los objetivos del presente estudio fueron evaluar el efecto de diferentes cultivos iniciadores y su concentración óptima, para reducir la carga microbiana y las aminas biogénicas en productos finales, con el objetivo de mejorar la seguridad de los embutidos sin deteriorar la aceptación sensorial. pH, aw, perfil microbiológico, aminas biogénicas, análisis del perfil de color y textura fueron evaluados. Las cepas y las concentraciones a utilizar, se seleccionaron en base a resultados previos: Staphylococcus xylosus, Lactobacillus sakei y una cepa de levadura a una concentración de 106 ufc / g de masa de carne cada una, se añadió 0,25% de dextrosa. Siempre se utilizó un lote control sin cultivos iniciadores. Los valores de aw fueron menores en los embutidos inoculados. En general, los valores de pH fueron ligeramente superiores en los embutidos inoculados. El tratamiento con L. sakei solo fue el más efectivo en la reducción del nivel de contaminación con L. monocytogenes, sin embargo este efecto parece perderse en cultivos mixtas. La inoculación, disminuyó generalmente el contenido de putrescina, de cadaverina y de tiramina. La inoculación de levadura parece contribuir al color más oscuro de los Paios. Con respecto a la textura, el Paio control demostró valores más altos de la dureza

QUANTIFILER®TRIO DNA method performance in a collection of ancient samples

Trabalho científico apresentado sob a forma de Poster no evento 9th ISABS Conference on Forensic Anthropologic Genetics and Mayo Clinicm Bol, Island of Brac, Croacia, 2015During the past few years significant progress has been made in solving technical challenges associated with STR profiling including the ability to analyze degraded DNA and low amounts of DNA. The result of these changes is that useful STR profiles can now be obtained from previously untypeable forensic DNA samples. Analysis of DNA from ancient material represents an important role in molecular anthropology, although there are many limitations concerning low DNA quantity and/or degraded DNA, and/or PCR inhibitors. These factors can make it difficult to decide whether to continue with STR analysis, which STR panel to use and how much DNA to add to PCR reaction. With all these constraints, DNA quantification represents an important tool to decide which method will follow in order to improve workflow and have good results in less time-consuming. The Quantifiler® Trio DNA method provides a quality index (QI) to detect the presence of degraded DNA along with PCR inhibitors.This guide allows the selection of the optimal short tandem repeat (STR) analysis chemistry (autosomal, or miniSTR) and streamlines the workflow while increasing downstream analysis success rates. In order to compare DNA quality from different extraction methods, samples from 46 exhumed Middle Ages individuals were extracted with modified phenol-chloroform method and also PrepFiler Express BTA™ method. DNA was quantified with Quantifiler® Trio DNA Quantification in an Applied Biosystems® 7500 Real-Time PCR System. Results were analyzed and allow us to point Quantifiler® Trio method as an important tool in pre-STR typing methods in ancient samplesN/

Staphylococcus spp. and Lactobacillus sakei Starters with High Level of Inoculation and an Extended Fermentation Step Improve Safety of Fermented Sausages

Paio do Alentejo (PA) is one of the most popular dry-fermented sausages in Portugal. The aim of the present work was to evaluate the effect of a high concentration of starter cultures with an extended fermentation step on the safety and quality of PA. Physicochemical parameters, microbiological parameters, biogenic amines, colour, texture profile, and sensory attributes were assessed. Five starters were selected based on our previous works. Staphylococcus equorum S2M7, Staphylococcus xylosus CECT7057, Lactobacillus sakei CV3C2, Lactobacillus sakei CECT7056, and a yeast strain (2RB4) were co-inoculated in meat batters at a concentration of 108 cfu/g for bacteria and 106 cfu/g for yeast strain, and 0.25% dextrose was added. Inoculated starters significantly reduced pH, Listeria monocytogenes counts, and total content in biogenic amines. The studied starter cultures did not compromise the sensory characteristics of PA, and thus, their use can be considered to protect these sausages and contribute to their safet

Post-depositional processes of elemental enrichment inside dark nodular masses of an ancient aeolian dune from A Coruña, Northwest Spain

This paper focuses on a residual ancient aeolian climbing dune from Punta Penaboa (A Coruña, Northwest Spain) showing evidence of post-depositional weathering, particularly the presence of dark brown nodular masses. The partitioning of trace elements between nodular masses and host sand during post-depositional weathering of the dune is investigated in this work, with the main objective of studying the elemental enrichment patterns in the dark masses. Data of the concentrations of chemical elements were obtained by instrumental neutron activation analysis (INAA) and complemented by mineralogical and microchemical studies, using X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) / energy dispersive X-ray spectrometry (EDS). The dune was dated by optically stimulated luminescence (OSL) , yielding an age of 300ka B.P.. The dark nodular masses preserved the dune sand structure, without defined concentric layers, suggesting an early stage of formation. They consist mainly of quartz grains cemented by clay materials enriched in the majority of the elements studied, especially in Mn, Co, Ba, Sb, Ce, Tb, Th, As, Zr and Hf. The post-depositional transformations of the dune were most likely influenced by migration of chemical compounds from the surrounding slope deposits and granitic rocks, as well as microbial activity that promoted metals concentration in the solutions percolating through the pore network of the dune. Seasonal changes in the redox potential were required to produce the accumulation of Mn and other trace elements in the dune pore network and to promote the fractionation between Ce4+ and trivalent rare earth elements that was observed in the geochemical patterns