Microbiological stability of canned tuna produced in italy and in non-european countries

The results of a study on the microbiological stability of canned tuna produced by Italian companies and similar canned products manufactured in countries outside Europe are reported herein. The study involved 38 samples of canned tuna of various brands, of which 14 were produced by companies outside Europe and 24 by Italian companies. Qualitative and quantitative microbiological tests were conducted for the following parameters: bacterial colony counts at 30\ub0C, total coliforms, total Enterobacteriaceae, sulphite-reducing anaerobes, Salmonella spp., Bacillus cereus, Escherichia coli, Staphylococcus aureus, yeasts and molds. Bacterial loads and mold contamination were respectivelyin found in 8/14 (57%) samples from outside EU and 7/24 (29%) Italian samples. The bacterial flora was represented by Gram-positive bacteria (Staphylococcus warneri, Staphylococcus lentus, Streptococcus mitis, Enterococcus faecalis, Leuconostoc mesenteroides), Gram-negative bacteria (Sphingomonas paucimobilis, Acinetobacter iwoffii, Rhizobium radiobacter), spore-forming bacteria (Bacillus vallismortis), while the fungal species was represented by Penicillium spp., Rhizopus spp., Rhodotorula spp. and Alternaria spp. Excluding anomalies in the thermal treatment process of products and any contamination after treatment, the contaminations encountered in both cases were most likely due to insufficient production quality standards and the quality of the raw material used. These results may require a redefinition of the concept of commercial stability as hitherto stated

Peces y pesca deportiva argentina : Mar y Patagonia.

Estamos ante una obra sobre ictiología, de características particulares, ya que aborda de una forma amena y descontracturada una serie de aspectos esenciales relacionados con esta disciplina. Describe en un lenguaje llano, conceptos fundamentales en el manejo y conservación de los recursos pesqueros.Reseña realizada por Hugo L. López y Diego O. Nadalin. División Zoología Vertebrados – Sección Ictiología, Museo de La Plata-Universidad Nacional de La Plata [email protected]

Detección y análisis de distribución de lamprea (geotria australis; gray, 1851) en Patagonia austral a través de adn ambiental

La lamprea de bolsa (Geotria australis) es una especie anádroma, única en su género, cuya presencia se encuentra restringida al hemisferio sur (Chile, Argentina, Australia y Nueva Zelanda). Se encuentra ampliamente distribuida en la Patagonia chilena, habitando ríos que desembocan en el Océano Pacífico. Por otro lado, la distribución de G. australis en la Patagonia argentina, no es del todo clara. En este sentido, si bien existen trabajos que reportan la presencia de esta especie en los ríos Negro, Chubut y en el estuario del río Gallegos, poco se sabe sobre la presencia y el patrón de distribución en el resto de la Patagonia. El ADN ambiental (ADNa) es un método no invasivo a través del cual es posible detectar la presencia de una especie a partir de una muestra de agua. El objetivo de este trabajo fue desarrollar un método basado en ADNa para detectar G. australis en ríos de la Patagonia Austral, con el fin de elaborar un mapa de distribución de esta especie. Para esto, se diseñó un set de primers específico que fue validado in silico, in vitro e in situ. El análisis in silico se realizó utilizando el software Primer Blast. Para la validación in vitro se realizó un ensayo de especificidad mediante PCR en Tiempo Real. Para esto, se utilizó como molde ADN total de las especies que cohabitan con la especie blanco. Para el último paso de validación (in situ), se tomaron muestras de agua a la vez que se confirmó la presencia de la especie por electropesca en el río Gallegos y tributarios del río Grande. Finalmente, se tomaron muestras de agua en 12 cuencas, logrando detectar G. australis por el método de ADNa en 8 de éstas. En este trabajo, proporcionamos el primer reporte de la presencia de G. australis en el extremo sur de la Patagonia, además del primer dato de presencia de esta especie en una cuenca que fluye hacia el Canal Beagle (río Lapataia).Fil: Nardi, Cristina Fernanda. Universidad Nacional de Tierra del Fuego, Antártida e Islas del Atlántico Sur. Instituto de Ciencias Polares, Recursos Naturales y Ambiente. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chalde, Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Daniel Fernández. Universidad Nacional de Tierra del Fuego, Antártida e Islas del Atlántico Sur. Instituto de Ciencias Polares, Recursos Naturales y Ambiente. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Casalinuovo, Miguel Angel. No especifíca;V Jornadas Patagónicas de Biología; III Jornadas Patagónicas de Ciencias Ambientales y VI Jornadas Estudiantiles de Ciencias BiológicasTrelewArgentinaUniversidad Nacional de la Patagonia San Juan Bosco. Facultad de Ciencias Naturales y Ciencias de la Salu

Presence of Mycobacterium bovis in slaughterhouses and risks for workers

An investigation was carried out to detect the presence of Mycobacterium bovis in slaughterhouses where intradermal tuberculin test positive cattle were slaughtered, and to evaluate the risk of contamination by M. bovis among exposed slaughterhouse workers. Swabs were taken from the carcasses of slaughtered animals showing autoptic signs of non-generalized forms of tuberculosis, thus authorized for free consumption. Swabs were also taken from the hands and clothes of the staff employed in the butchery production line. Environmental samplings were conducted on the slaughterhouse air using filters and air aspiration devices, and on water used to wash the carcasses after slaughter. Samples from the carcasses of healthy animals were also taken on a following slaughtering session. The swabs were analysed by means of Polymerase Chain Reaction for the detection of mycobacteria. M. bovis was detected on meats, on the hands of one worker, and in the washing water. The results obtained from this study confirm that workers are highly exposed to infection by zoonotic tuberculosis, and that cleaning procedures were ineffective in our setting

Least Square Regression Method for Estimating Gas Concentration in an Electronic Nose System

We describe an Electronic Nose (ENose) system which is able to identify the type of analyte and to estimate its concentration. The system consists of seven sensors, five of them being gas sensors (supplied with different heater voltage values), the remainder being a temperature and a humidity sensor, respectively. To identify a new analyte sample and then to estimate its concentration, we use both some machine learning techniques and the least square regression principle. In fact, we apply two different training models; the first one is based on the Support Vector Machine (SVM) approach and is aimed at teaching the system how to discriminate among different gases, while the second one uses the least squares regression approach to predict the concentration of each type of analyte

Phenotypic antimicrobial resistance profile of isolates causing clinical mastitis in dairy animals

Mastitis is the most frequent and costly disease of lactating animals and is associated with a significant reduction in milk yield, increased cost and culling. Early and specific antibiotic based treatment reduces the severity of the disease. Over the years the extensive use of antimicrobials has led to increase antimicrobial resistance. The present study was designed to investigate the prevalence of microorganisms responsible for mastitis and their antimicrobial resistance pattern. A total of 282 milk samples were collected from different animal species (sheep, cows and goats) with clinical mastitis. Antimicrobial resistance was evaluated for Streptococcus spp. and Staphylococcus spp. In cow samples Streptococcus spp. represented the most frequently isolated genus (33.84%), while Staphylococcus spp. was the most prevalent genus in sheep and goat samples (44.4 and 73.86%, respectively). Gentamicin and chloramphenicol were found to be the most effective drugs against the tested isolates, while the highest resistance rates were observed for amoxicillin, ampicillin, tetracycline, trimethoprim-sulfamethoxazole

Device-independent, real-time identification of bacterial pathogens with a metal oxide-based olfactory sensor

A novel olfactory method for bacterial species identification using an electronic nose device called the MonoNose was developed. Differential speciation of micro-organisms present in primary cultures of clinical samples could be performed by real-time identification of volatile organic compounds (VOCs) produced during microbial replication. Kinetic measurements show that the dynamic changes in headspace gas composition are orders of magnitude larger than the static differences at the end of fermentation. Eleven different, clinically relevant bacterial species were included in this study. For each of the species, two to eight different strains were used to take intra-species biodiversity into account. A total of 52 different strains were measured in an incubator at 37°C. The results show that the diagnostic specificities varied from 100% for Clostridium difficile to 67% for Enterobacter cloacae with an overall average of 87%. Pathogen identification with a MonoNose can be achieved within 6–8 h of inoculation of the culture broths. The diagnostic specificity can be improved by broth modification to improve the VOC production of the pathogens involved

Switchable disposable passive RFID vapour sensors from inkjet printed electronic components integrated with PDMS as a stimulus responsive material

A route to cheap and disposable sensors for the chemical sensing market, with potential applications including monitoring of food spoilage, is reported herein. The sensor is the result of the direct integration of a stimuli-responsive material, poly(dimethylsiloxane) (PDMS), with an electronic component. The printing and sintering of colloidal silver ink solutions onto PDMS was optimized to allow the printing of conductive silver feed loops, which are the active sensing component in antennas for passive (battery-free) Radio Frequency Identification (RFID) tags. The response of these devices is related to the degree of swelling of the PDMS, which, in turn, has been shown to be correlated to the Hansen solubility parameters and the vapour pressures of the corresponding volatile organic compounds (VOCs). When exposed to solvent vapour the printed feed loop fractures, increasing resistance and ultimately breaking conductivity, leading to a change in the transmitted power and read range of the wireless device. Remarkably upon removal from the vapour, the fractured feed loops reassemble and become conductive again, making them switchable and “multi-use”. This work paves the way to a fully inkjet printed RFID substrate for vapour detection

Local and transboundary transmission of methicillin-resistant Staphylococcus aureus sequence type 398 through pig trading

Livestock-associated methicillin-resistant Staphylococcus aureus sequence type (ST) 398 (LA-MRSA ST398) is a genetic lineage for which pigs are regarded as the main reservoir. An increasing prevalence of LA-MRSA ST398 has been reported in areas with high livestock density throughout Europe. In this study, we have investigated the drivers contributing to the introduction and spread of LA-MRSA ST398 along the pig farming system in Southern Italy. Whole-genome sequencing (WGS) of LA-MRSA ST398 isolates collected in 2018 from pigs (n=53) and employees (n=14) from 10 farms in the Calabria region were comparatively analysed with previously published WGS data from Italian ST398 isolates (n=45), an international ST398 reference collection (n=89) and isolates from Danish pigs farms (n=283), which are the main suppliers of pigs imported to Italy. Single-nucleotide polymorphisms (SNP) were used to infer isolates relatedness and, together with data from animal trading, factors contributing to LA-MRSA ST398 dissemination were identified. The analyses support the existence of two concurrent pathways for the spread of LA-MRSA ST398 in Southern Italy: i) multiple introductions of LA-MRSA ST398 through the import of colonized pigs from other European countries including Denmark and France and; ii) the spread of distinct clones dependent on local trading of pigs between farms. Phylogenetically related Italian and Danish LA-MRSA ST398 isolates shared extensive similarities including carriage of antimicrobial resistance genes. Our findings highlight the potential risk of transboundary transmission of antimicrobial-resistant bacterial clones with a high zoonotic potential when importing pigs from countries with high LA-MRSA prevalence

A humid electronic nose based on pulse voltammetry: A proof-of-concept design

[EN] We report herein the design, manufacture and use of a "humid electronic nose" prototype based on voltammetric techniques. It consists of an array of four working electrodes (i.e., Au, Pt, Ir and Rh) housed inside a homemade stainless steel cylinder, in contact with a fabric mesh made of nylon damped with a NaCl aqueous solution, used as the supporting humid membrane. The "humid electronic nose" was tested for the discrimination of different samples displaying different volatile compounds. The samples chosen involve aqueous solutions of different simple volatile products (i.e., ammonia, acetone, acetic acid and 6-amino-1-hexanol) and different food samples (i.e., onion, coffee and Roquefort cheese). Under working conditions, the volatile compounds from the corresponding sample were generated in the measurement chamber and were partially dissolved in the damped nylon fabric, which was in contact with the set of electrodes. It was envisioned that provided different samples offer different vapours, the application of a suitable set of pulses to the electrodes will differentiate the samples. This proof-of-concept study employed a Large Amplitude Pulse Voltammetry (LAPV) waveform. The increment for the potential steps was of 200 mV and potentials ranged from +1 to -1 V with each pulse applied for 50 ms. PCA studies from the response obtained by the "humid electronic nose" discriminated the different samples studied. The neural network Self Organized Map (SOM) was also used to analyze the electrochemical data obtained from the "humid electronic nose". © 2013 Elsevier B.VThe financial support from the Spanish Government (project MAT2012-38429-C04) and the Generalitat Valenciana (Valencian Regional Government; projects PROMETEO/2009/016 and GV/2012/094); is gratefully acknowledged.Bataller Prats, R.; Campos Sánchez, I.; Alcañiz Fillol, M.; Gil Sánchez, L.; García Breijo, E.; Martínez Mañez, R.; Pascual Vidal, L.... (2013). A humid electronic nose based on pulse voltammetry: A proof-of-concept design. Sensors and Actuators B: Chemical. 186:666-673. https://doi.org/10.1016/j.snb.2013.06.033S66667318