Search

High-pressure processing ( HPP) has been shown to enhance and accelerate infusion of molecules compared with osmosis-driven diffusion. The primary cause for enhanced HPP infusion is attributed to cell membrane permeabilization. This study tests the validity of this commonly accepted mechanism by conducting HPP (100 MPa-551 MPa) infusion of quercetin into cranberries. Two systems used in this study were fresh cranberries, cells of which are intact, and frozen-thawed cranberries, cells of which are permeabilized during freeze-thaw process. Results showed that while fresh and frozen-thawed cranberries had similar cell membrane permeability after HPP, twice as much quercetin was infused into fresh cranberries as compared with frozen-thawed cranberries. If cell membrane permeability were the only cause of infusion, the amount of quercetin infused into cranberries in both systems should have been same. These results suggest that enhanced infusion caused by HPP is not just caused by cell permeabilization alone. Practical Applications Conventional diffusion based mass transport methods, currently used in the food industry for infusion, are slow processes. In order to accelerate the mass transport, this research investigated the potential of HPP to enhance and accelerate infusion in cranberries. The present study was focused on the comparison of infusion during HPP using fresh cranberries, cells of which were intact and frozen-thawed cranberries, cells of which were permeabilized (with ruptured cell membranes) by freeze-thaw process. Results showing increased infusion in fresh cranberries and similar cell permeability in both fresh and frozen-thawed cranberries suggested that enhanced infusion during HPP was not caused only by cell permeabilization. This research opens new avenues for investigating additional mass transport mechanisms occurring during HPP, which will help develop accurate predictive mass transport models for HPP infusion processes. [ABSTRACT FROM AUTHOR]

The amphibian micronucleus test has been widely used during the last 30 years to test the genotoxic properties of several chemicals and as a tool for ecogenotoxic monitoring. The vast majority of these studies were performed on peripheral blood of urodelan larvae and anuran tadpoles and to a lesser extent adults were also used. In this study, we developed protocols for measuring micronuclei in adult shed skin cells and larval gill cells of the Italian crested newt ( Triturus carnifex). Amphibians were collected from ponds in two protected areas in Italy that differed in their radon content. Twenty-three adult newts and 31 larvae were captured from the radon-rich pond, while 20 adults and 27 larvae were taken from the radon-free site. The animals were brought to the laboratory and the micronucleus test was performed on peripheral blood and shed skins taken from the adults and on larval gills. Samples from the radon-rich site showed micronucleus frequencies higher than those from the radon-free site and the difference was statistically significant in gill cells ( P < 0.00001). Moreover, the larval gills seem to be more sensitive than the adult tissues. This method represents an easy (and noninvasive in the case of the shed skin) application of the micronucleus assay that can be useful for environmental studies in situ. Environ. Mol. Mutagen. 56:412-417, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The Mediterranean Sea is currently under siege by a conspicuous alien pressure, and, within some families (e.g. the Ostreidae), the number of native species seems to be remarkably outnumbered by that of the alien ones. We wanted to test the reliability of the molecular data currently available on the small alien oysters recently invading the Mediterranean Sea. Samples from Greece and Turkey, encompassing the known species-specific morphological variation, were sequenced for the markers with the widest taxonomic coverage in the group of small oysters (i.e. the 16S rDNA and the COI). The sequences obtained have been compared with those available in GenBank, and a possible identification at the species level has been finally tested in a DNA-barcoding fashion. The present results clearly demonstrated that our samples belong to a single, morphologically highly variable species. Their 16S sequences were closely related to a sequence registered under the name Dendostrea folium, with a genetic distance which does not warrant conspecificity. Additionally, a remarkable number of sequences retrieved from the GenBank (of both genes) did not form a monophyletic group according to the published classification of the vouchers, suggesting—at least in part—an origin from specimens not properly identified. Both genes seem promising for use as DNA-barcode, although the COI will probably prove more effective. Therefore, we urge the availability of a baseline of oyster pedigreed DNA barcode sequences in the public databases, to allow the use of such genetic data to reliably monitor bio-invasions in the Mediterranean Sea. [ABSTRACT FROM PUBLISHER]

Biological invasions have become a major cause of biodiversity loss. Tracing the origin of the populations of alien species is essential to infer the dispersal pathway and finally to set conservation policies aimed at preventing new introductions. The Italian wall lizard,Podarcis sicula, is one of the reptile species most widely introduced, with allochthonous populations occurring from the United States to Turkey. For some of them, instances of geographic expansion and competition/hybridization with autochthonousPodarcissp. have been indicated. In the Iberian Peninsula, five introduced populations are known: Lisbon (W Portugal), Noja, Cantabria (N Spain), La Rioja (N Spain) and Almería (S Spain) and Sant Celoni, Barcelona (NE Spain) while the species now widely ranges Menorca Island in the Balearics. Here we assess the origin of four populations (Barcelona population will not be included) by comparing in a phylogenetic framework the cytochromebgene sequences of specimens from the introduced and native populations. The results from this study provide evidence for distinct sources, pathways, and timing of introduction in Iberian Peninsula and Balearics byP. siculafrom Tuscany, Calabria, Sicily, and Sardinia. This finding underpins the fact thatP. siculaholds considerable potential invasiveness and advises for conservation strategies based on a global and preventive plan for avoiding new introductions as well as on eradication and control measures when prevention fails. [ABSTRACT FROM AUTHOR]

Ballast water transported in ocean going vessels has been demonstrated to introduce invasive aquatic species during the de-ballasting operations at ports of destinations around the world. Continuous microwave heating in focusing cavities can be applied as a treatment to ballast water to eliminate these invasive species. This paper presents the first attempt to numerically model the temperature and flow distribution in ballast water heated through a continuous focused microwave system. The model was developed by coupling the High Frequency Electromagnetic Module and FLOTRAN CFD Module in the finite element analysis software ANSYS Multiphysics™ (Pittsburg, PA), and the numerical results were validated against experimental data at different salinities using model ballast water (0 and 1.5%) heated in a 915 MHz focused microwave unit at 4.5 kW incident power. The average absolute errors between the experimental and modeling data were approximately 3°C and 3.9°C for the 0% and the 1.5% salinity studies, respectively. Several parameters were investigated with respect to their influence on the ballast water temperature, including water salinity (0 and 1.5%) and flow rate (1 and 1.6 lpm). The highest temperature increase (ΔT of 40°C) was achieved for the 1.5% salinity water at 1 lpm, while the lowest temperature increase (ΔT of 6°C) was observed for the 0% salinity water at 1.6 lpm. The power loss was numerically determined to be 0.7 kW for 0% water, respectively 2.5 kW for the 1.5% saltwater. The developed model was helpful in understanding the process of continuous microwave heating of ballast water and the effects of salt content and flow rates on the temperature profile of ballast water for temperatures below boiling. The model can be used as a tool by researchers and engineers interested in designing continuous microwave systems for heat treatment applications of ballast water. [ABSTRACT FROM AUTHOR]