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Venta Micena is an area containing several palaeontological sites marking the beginning of the Calabrian stage (Early Pleistocene). The richness of the fossil accumulation including species of Asian, African and European origin, makes Venta Micena a key site for the the palaeoecological and palaeoenvironmental study of southern Europe during the Early Pleistocene. Thus, research has been focused on Venta Micena 3, which was originally interpreted as a single palaeosurface associated with a marshy context, in which most of the fauna was accumulated by Pachycrocuta brevirostris. Recent excavations have unearthed a new site, Venta Micena 4, located in the same stratigraphic unit (Unit C) and in close proximity to Venta Micena 3. Here we show the frst analyses regarding the taphonomic and spatial nature of this new site, defning two stratigraphic boundaries corresponding to two diferent depositional events. Furthermore, the taphonomic analyses of fossil remains seem to indicate a diferent accumulative agent than Pachycrocuta, thus adding more complexity to the palaeobiological interpretation of the Venta Micena area. These results contribute to the discussion of traditional interpretations made from Venta Micena 3., Regional Government of Andalusia, with both contracts associated to General Research Project BC.03.032/17, Spanish Public Employment Service (Spanish Ministry of Labour and Social Economy), Spanish Ministry of Science, Innovation and Universities, with an FPI Predoctoral Grant (Reg. PRE2019-089411) associated to project RTI2018-099850-B-IOO and the University of Salamanca, Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA) has received fnancial support from the Spanish Ministry of Science and Innovation through the “María de Maeztu” program for Units of Excellence (CEX2019-000945-M), Projects 2017SGR-859 (Gov. of Catalonia, AGAUR), and CGL2016-80000-P (Spanish Ministry of Economy and Competitiveness), Research Group HUM-607 (Junta de Andalucía).

Producción Científica, The technical feasibility of valorizing tequila vinasse (TV), a wastewater with high pollution potential, through the production of biogenic hydrogen via dark fermentation, has long been proven in diverse lab-scale reactors that were operated either in batch or continuous mode. However, such systems have mainly been tested with diluted streams and nutrient supplementation, hindering the techno-economic attractiveness of the TV-to-hydrogen concept at large scale. In this study, the feasibility of producing hydrogen from high-strength undiluted TV with no added extra nutrients was evaluated under batch mesophilic conditions. Additionally, the use of two different acidogenic inocula obtained either by heat or heat-aeration pretreatment was investigated to get a greater understanding of the effect of inoculum type on the process. The results obtained showed that the TV utilized herein contained macro- and micro-nutrients high enough to support the hydrogenogenic activity of both cultures, entailing average hydrogen yields of 2.4–2.6 NL H2/L vinasse and maximum hydrogen production rates of 1.4–1.9 NL H2/L-d. Interestingly, the consumption of lactate and acetate with the concomitant production of butyrate was observed as the main hydrogen-producing route regardless of the inoculum, pointing out the relevance of the lactate-driven dark fermentative process. Clostridium beijerinckii was ascertained as key bacteria, but only in association with microorganisms belonging to the genera Enterobacter and Klebsiella, as revealed by phylogenetic analyses., Consejo Estatal de Ciencia y Tecnología de Jalisco (COECYTJAL; 8872–2020).

In this paper we analyse the taphonomic signatures of captive jaguars (Panthera onca) in order to explore the potential of experimental frameworks to distinguish between different felid agents in carnivore-altered palaeontological and archaeological bone assemblages. Many papers have considered carnivore ecology and the bone altering behaviour of different animals since the development of taphonomic research since the 1980's, as part of the hunter vs scavenging debate to understand early hominin sites. Hyenas have been the most studied carnivore, followed by felids and lastly canids. Within felids, lions and leopards have been the focus of most research, whereas other agents, such as jaguars or tigers are still relatively uncharacterised taphonomically. Here we present the results of an experimental feeding program to assess the nature and extent of alterations that captive jaguars can produce on horse (Equus ferus caballus) appendicular bones. Working with captive animals has some limitations, namely the generally greater extent of alterations on captive-analysed assemblages in relation to their wild counterparts. Despite this issue, we aim to start developing a broader referential framework of felid ethology that includes jaguars, a relevant taphonomic agent for understanding bone assemblages of the European and American Pleistocene. Therefore, in this preliminary study on the taphonomy of jaguars, we aim to show their prowess as bone-altering agent, capable of generating tooth-marks on long limb bone diaphyses and epiphyseal deletion. The taphonomic behaviour of jaguars has not been documented experimentally in any detail so far.

We report an interesting case of a T lymphoblastic lymphoma (T-LBL) with uncommon CD20 expression. Immunophenotype analysis showed TdT expression with positivity of CD3 and CD7 among other T-lineage markers. Other non-T markers such as CD79a or myeloid-associated antigens were negative. Molecular studies were performed evidencing clonal rearrangements for gamma and beta chain T cell receptor were clonal in the lymph node biopsy. Cytogenetic analysis showed deletions in CDKN2A and NOTCH2 genes. CD20 when present in T-LBL can lead to a false diagnosis of B-LBL. In this scenario, analysis of rearrangements of both immunoglobulin heavy chain B cell receptor and rearrangement of the T cell receptor can be very helpful.

Recent studies using geometric morphometrics for taphonomy have yielded interesting results, opening new horizons of research in both archaeological and paleontological sites. Here we present the analysis of tooth pits left by male and female individuals of two different carnivore species (Panthera tigris and Panthera pardus) in order to see if sexual dimorphism influences the morphology of tooth pit marks. In the process, 3D-scanning and applied statistics were used. Based on samples derived from two individuals of different sexes, the present results indicate sexual dimorphism in these felid species to not be a conditioning factor of tooth pit morphology.

[EN] More than 12,000 plant species (ca. 10% of flowering plants) exude latex when their tissues are injured. Latex is produced and stored in specialized cells named "laticifers''. Laticifers form a tubing system composed of rows of elongated cells that branch and create an internal network encompassing the entire plant. Laticifers constitute a recent evolutionary achievement in ecophysiological adaptation to specific natural environments; however, their fitness benefit to the plant still remains to be proven. The identification of Euphorbia lathyris mutants (pil mutants) deficient in laticifer cells or latex metabolism, and therefore compromised in latex production, allowed us to test the importance of laticifers in pest resistance. We provided genetic evidence indicating that laticifers represent a cellular adaptation for an essential defense strategy to fend off arthropod herbivores with different feeding habits, such as Spodoptera exigua and Tetranychus urticae. In marked contrast, we also discovered that a lack of laticifer cells causes complete resistance to the fungal pathogen Botrytis cinerea. Thereafter, a latex-derived factor required for conidia germination on the leaf surface was identified. This factor promoted disease susceptibility enhancement even in the non-latex-bearing plant Arabidopsis. We speculate on the role of laticifers in the coevolutionary arms race between plants and their enemies., This work was supported by a grant from the Agencia Estatal de Investigacion (AEI), Spain (RTI2018-098501-B-I00).

Developing new distillation strategies can help the spirits industry to improve quality, safety and process efficiency. Batch stills equipped with a packed column and an internal partial condenser are an innovative experimental system, allowing a fast and flexible management of the rectification. In this study, the impact of four factors (heart-cut volume, head-cut volume, pH and cooling flow rate of the internal partial condenser during the head-cut fraction) on 18 major volatile compounds of Muscat spirits was optimized using response surface methodology and desirability function approaches. Results have shown that high rectification at the beginning of the heart-cut enhances the overall positive aroma compounds of the product, reducing off-flavor compounds. In contrast, optimum levels of heart-cut volume, head-cut volume and pH factors varied depending on the process goal. Finally, three optimal operational conditions (head off-flavors reduction, flowery terpenic enhancement and fruity ester enhancement) were evaluated by chemical and sensory analysis.

In this work, we compare the effect of the addition during fermentation of both sodium bentonite and sodium-activated bentonite on the protein content, protein stability, lees volume, and aroma compounds of a Sauvignon blanc wine. Protein unstable Sauvignon blanc juices were vinified with or without bentonite added at three different stages: before fermentation, early during fermentation, and towards the end of fermentation. Different addition doses of bentonite were used (X, X − 0.1, X − 0.2 g/L) according to protein instability of the grape juice (X = 1.7 and 2.7 g/L to sodium bentonite and sodium-activated bentonite, respectively). The wines stabilized with sodium-activated bentonite presented a higher content of volatile compounds and a lower volume of lees were produced than those treated with sodium bentonite, an effect that was greater when the fining treatment was done before the start of the fermentation.

Vanadium is a widely distributed metal in the Earth’s surface and is released into the environment by either natural or anthropogenic causes. Vanadium (III) oxide (V2O3) is present in the environment, and many organisms are exposed to this compound; however, its effects at the cellular and genetic levels are still unknown. Therefore, in this study, the ability of V2O3 to induce chromosomal damage and impair cell proliferation was tested on human leukocytes in vitro. The cultures cells were treated for 48 h with different concentrations 2, 4, 8 or 16 μg/mL of V2O3, and we use the sister chromatid exchange’s (SCE) test and the viability assay to evaluate the effects.In the results, no change was observed in either the viability or the frequency of SCE; however, a significant increase was observed in the incidence of premature chromatid separation (PCS), and a decrease was observed in both the mitotic index (MI) and the replication index (RI). Therefore, it can be suggested that V2O3 induces a genoto...

The objective of this study was to identify genetic single nucleotide polymorphisms (SNPs) in the coding region of the KRTAP11.1 gene from the Suri alpaca population from Puno, Peru. Genomic DNA (n = 119) was used to amplify the 636 bp fragment of the coding region from the KRTAP11.1 gene. The polymerase chain reaction products of the KRTAP11.1 gene were sequenced by both strands and polymorphism type SNPs were identified. All SNPs (n = 3) were in Hardy-Weinberg equilibrium and had a high level of genotypic linkage disequilibrium with the presence of two haplotypes. All genetic polymorphisms generate non-synonymous amino acids changes: SNP 110 T>G (Ser>Ala), SNP 363 T>G (Phe>Cys) and SNP 375 A>C (Tyr>Ser). The results indicated the presence of moderate genetic diversity in the coding region of the KRTAP11.1 gene from the Suri alpaca population.

Aims: The aim of this study was the genetic diagnosis by next generation sequencing (NGS) of a patient diagnosed with Usher syndrome type 2 and the functional evaluation of the identified genetic variants to establish a phenotype&ndash, genotype correlation. Methods: Whole exome sequencing (WES) analysis identified two heterozygous intronic variants in CDH23, a gene responsible of Usher syndrome type 1. Evaluation of the putative splicing effects was performed in vivo, in whole blood samples, and in vitro, by transfection of midigene constructs in HEK293T cells. Results: Two intronic variants were identified in intron 45 of CDH23&mdash, one novel, c.6050-15G&gt, A, and the other, c.6050-9G&gt, A, already reported as a noncanonical splice site (NCSS) mutation&mdash, with partial functional characterization. In vivo and in vitro analyses showed aberrant transcripts by the addition of 13 and 7 nucleotides to exon 46, respectively. Transcript degradation by nonsense mediated decay (NMD) in blood cells could only be prevented by cycloheximide treatment. Midigene constructs showed that the two variants contributed to exon skipping and generated aberrantly spliced transcripts. Conclusions: A combination of in vivo and in vitro assays provided a comprehensive view of the physiological effects of NCSS variants, which in this case led to a clinical reassignment of the proband as affected with atypical USH1 syndrome.

Deoxynivalenol (DON) is a mycotoxin produced mainly by Fusarium species and occurs predominantly in cereal grains such as wheat. Due to its toxic effects, in the European Union DON content in unprocessed cereals and processed cereal-based products for human consumption has been regulated, and recommended maximum limits have been established for animal feed. In this study, a method for degrading DON on wheat kernels, by exposition to ammonia (NH3) vapours, was optimized. Results have shown that with a simple treatment with ammonia vapours at 90ºC (for two hours), degradations higher than 75% were achieved in kernels affected by a moderated contamination up to 2000 µg/kg DON. The study of the reaction between DON and NH3 allowed us to tentatively establish the structure of possible degradation products. In addition, in silico evaluation indicated, in general, lower toxicity and biological effects for the degradation products than for DON. B.B.-V. and J. J R.-B. appreciate the FD pre-doctoral fellowship (PRE2018-085278) of the Spanish Ministry of Science, Innovation and Universities, and the postdoctoral contract from Agrotecnio center, respectively. This work was funded through the project AGL2017-87755-R awarded by the Spanish Ministry of Science, Innovation and Universities.

Casiopeina III-Ea® (Cas III-Ea®) is a chelated copper complex with antineoplastic activity that is capable of reducing tumor size and inducing antiproliferative and apoptotic effects. However, little is known about its in vivo genotoxic effects. Therefore, this study evaluated two cytogenetic and two proliferative parameters 24 h after the administration of Casiopeina III-Ea® to male CD-1 mice. Three doses of Cas III-Ea® were administered by intraperitoneal injections of 1.69, 3.39 and 6.76 mg/kg (corresponding to 1/8, 1/4 and 1/2 of LD50, respectively). A reduction in the mitotic index (MI) and an increased numbers of cells with structural chromosomal aberrations (SCA) were detected. Additionally, a low but significant increase in the frequency of sister chromatid exchange (SCE) was observed at the highest dose. Changes in the DNA replication index (RI) were not observed. These results indicate that Casiopeina III-Ea® shows cytotoxic and clastogenic activity in bone marrow cells from treated mice.

A variety of metal ions have biological functions, and many researchers have not actively investigated copper compounds, based on the assumption that endogenous metals might be less toxic. In the present study, we used a dual fluorochrome method and a single cell gel electrophoresis (SCGE) assay at pH > 13 to evaluate the cell viability and DNA damage induced by a copper-based antineoplastic drug, Casiopeina II-gly®, at concentrations of 1.04, 2.08, 4.17, 8.35 or 16 μg/mL in human peripheral-blood leukocytes in vitro. We observed that Casiopeina II-gly® reduced cell viability at high concentrations (8.35 and 16 μg/mL) and induced DNA damage characterized by single-strand breaks and alkali labile sites at several concentrations from 2.08 to 16 μg/mL. This chemical clearly affected DNA migration in a concentration- and time-dependent manner and induced genotoxic effects in few minutes (>20 min), at which point the genotoxicity was followed by cytotoxicity.

13 pages, 1 table, 8 figures, The variation in microbial composition over time was assessed in biofilms formed in situ on selected non-food and food contact surfaces of meat and fish industries, previously identified as Listeria monocytogenes-positive foci. First, all samples were analysed for the detection and quantification of L. monocytogenes using ISO 11290-1 and ISO 11290-2 norms, respectively. Although the pathogen was initially detected in all samples, direct quantification was not possible. Psychrotrophic bacteria counts were among resident microbiota in meat industry samples (Meanmax = 6.14 log CFU/cm2) compared to those form fish industry (Meanmax = 5.85 log CFU/cm2). Visual analysis of the biofilms using epifluorescence microscopy revealed a trend to form microcolonies in which damaged/dead cells would act as anchoring structures. 16S rRNA gene metagenetic analysis demonstrated that, although Proteobacteria (71.37%) initially dominated the bacterial communities at one meat industry location, there was a dramatic shift in composition as the biofilms matured, where Actinobacteria (79.72%) became the major phylum present in later samples. This change was largely due to an increase of Nocardiaceae, Micrococcaceae and Microbacteriaceae. Nevertheless, for the other sampling location, the relative abundance of the dominating phylum (Firmicutes) remained consistent over the entire sampling period (Mean = 63.02%). In fish industry samples, Proteobacteria also initially dominated early on (90.69%) but subsequent sampling showed a higher diversity in which Bacteroidetes and Proteobacteria were the most abundant phyla accounting for the 48.04 and 37.98%, respectively by the last sampling period. Regardless of the location, the community profiles of the endpoint samples were similar to those reported previously. This demonstrated that in a given industrial setting there is a trend to establish a determinate biofilm structure due to the environmental factors and the constant incoming microbiota. This information could be used to improve the existing sanitisation protocols or for the design of novel strategies, The Spanish Ministry of Science, Innovation and Universities [SOLISTA, AGL2016-78549] financially supported this research

12 pages, 6 figures, 3 tables, The main aim of this study was to localise, identify and characterise the Listeria monocytogenes-harbouring bacterial communities present in food related premises via 16S rRNA gene metagenetic analysis. With this scope, 319 environmental samples coming from a wide variety of surfaces of fish (n = 120), meat (n = 80) and dairy industries (n = 119), were firstly analysed following ISO 11290–1 and ISO 11290–2 norms. Direct L. monocytogenes quantification was possible in 9 samples (2.8%) with values between 2.00 and 3.97 log CFU/cm2. After enrichment, an overall L. monocytogenes incidence of 12.54% (n = 40) was obtained, being samples from meat industry the most contaminated. Molecular serotyping assays showed that most of the isolates belonged to 1/2b-3b-7 subgroup, followed by 1/2a-3a and 1/2c-3c. These results combined with AscI and ApaI PFGE macrorestriction patterns, yielded 7 different L. monocytogenes clusters. Nevertheless, no clear ecological relationships could be stablished. High amounts of L. monocytogenes-associated psychrotrophic microbiota were obtained in all cases with values above 9 log CFU/cm2 in some cases. Metagenetic analysis of one representative sample per each food industry type (fish, meat, dairy) demonstrated that Actinobacteria (53.16%) was mostly present in the meat sample whereas Proteobacteria was the most representative phylum in dairy (69.58%) and fish (97.11%) samples. Subsequent operational taxonomic units (OTUs) analysis, showed a wide variety of taxa associated with L. monocytogenes such as spoilage-associated genera (e.g. Psyschromonas or Shewanella), lactic acid bacteria genera (e.g. Lactococcus or Lactobacillus) or pathogenic species such as Yersinia enterocolitica. It was thus demonstrated, that L. monocytogenes is capable to both survive with different bacteria in different ecological niches, highlighting once more the need for proper surveillance schedules so as to guarantee the safety of the food products, This research was financially supported by the Spanish Ministerio de Economía, Industria y Competitividad [SOLISTA, AGL2016-78549]

Although many efforts have been made to control Listeria monocytogenes in the food industry, growing pervasiveness amongst the population over the last decades has made this bacterium considered to be one of the most hazardous foodborne pathogens. Its outstanding biocide tolerance capacity and ability to promiscuously associate with other bacterial species forming multispecies communities have permitted this microorganism to survive and persist within the industrial environment. This review is designed to give the reader an overall picture of the current state-of-the-art in L. monocytogenes sessile communities in terms of food safety and legislation, ecological aspects and biocontrol strategies., Authors P.R.-L., J.J.R.-H. and M.L.C. acknowledge the Spanish Ministerio de Economía, Industria y Competitividad (MINEICO) for its financial support (Project: SOLISTA; AGL2016_78549). Author D.V.-S. was financially supported by a research grant of the São Paulo Research Foundation (FAPESP, 2014/20590-0).

Today, bentonite continues to be one of the most used products to remove proteins in white wines in order to avoid their precipitation in bottles. However, excessive use of bentonite has negative effects on the aroma of final wine, so the optimization of the dose and the time of its application are important for winemakers. This paper analyzes how applying an equal dose of bentonite at different stages (must clarification; beginning, middle, and end of fermentation) affects the macromolecular profile, protein stability, physical-chemical characteristics and aromatic profile of the wine obtained. The results showed the addition during fermentation (especially in the middle and at the end) reduced the total dose required for protein stabilization of Albariño wines and maintained the sensory characteristics of this variety.

This chapter presents an overview of fruit distillates, describing the different types of distillates according to type of fruit: pome fruits, stone fruits, and berries, as well as the basis of their legal characteristics, distinguishing alcoholic beverages by fruit brandies, distillates obtained from macerated fruits, and liqueurs. Brandies of traditional fruits are analyzed, such as those obtained from pears, apples, cherries, and plums, as well as brandies from less common fruits such as melon, kiwi, and mango. Finally, this chapter analyzes the potential of berries, especially their possible use in the production of liqueurs.

[EN] In the latex-bearing plants, the laticiferous system is the tubing structure that contains the latex and is constituted of living cells (laticifers). While laticifers are present only in a small percentage of the flowering plant species, they represent a type of specialized tissue within the plant where a myriad of metabolites are synthesized, some of them of considerable commercial importance. In this mini-review we synopsize the present knowledge about laticifer cells and discuss about their particular features as well as some evolutionary and ecophysiological cues and the potential exploitation of the knowledge generated around this peculiar type of plant cell. We illustrate some of these questions with the experience in Euphorbia lathyris laticifers and latex., This work was supported by the Spanish MINECO (BFU2015-68199-R to P.V.) and Generalitat Valenciana (Prometeo 2014/024 to P.V.)

New types of wine-derived beverages are now in the market. However, little is known about the impact of ingredient formulation on aroma release during consumption, which is directly linked to consumer preferences and liking. In this study, the optimization and validation of a retronasal aroma-trapping device (RATD) for the in vivo monitoring of aroma release was carried out. This device was applied to assess the impact of two main ingredients (sugar and ethanol) in these types of beverages on in vivo aroma release. Two aroma-trapping materials (Lichrolut and Tenax) were firstly assayed. Tenax provided higher recovery and lower intra- and inter-trap variability. In in vivo conditions, RATD provided an adequate linear range (R2 > 0.91) between 0 and 50 mg L−1 of aroma compounds. Differences in the total aroma release were observed in equally trained panelists. It was proven that the addition of sugar (up to 150 mg kg−1) did not have effect on aroma release, while ethanol (up to 40 mg L−1) enhanced the aroma release during drinking. The RATD is a useful tool to collect real in vivo data to extract reliable conclusions about the effect of beverage components on aroma release during consumption. The concentration of ethanol should be taken into consideration for the formulation of wine-derived beverages., This work was funded by the MINECO (AGL2012-04172-CO2-01 and CONSOLIDER INGENIO 2010 (FUN-C-FOOD, CSD2007-063)

Although thallium is detrimental to all living organisms, information regarding the mutagenic and genotoxic effects of this element and its compounds remains scarce. Therefore, we tested the genotoxic and cytotoxic effects of thallium(I) acetate on human peripheral blood cells in vitro using structural chromosomal aberrations (SCAs), sister chromatid exchanges (SCEs), and single-cell gel electrophoresis (at pH >13 or 12.1) analysis. Whole blood samples were incubated with 0.5, 1, 5, 10, 50, or 100 µg/mL thallium salt. Exposure to this metal compound resulted in a clear dose-dependent reduction in the mitotic and replicative indices. An increase in SCAs was evident in the treated group compared with the control group, and significant differences were observed in the percentage of cells with SCAs when metaphase cells were treated with 0.5–10 µg/mL of thallium(I). The SCE test did not reveal any significant differences. We observed that a 1-h treatment with thallium(I) at pH > 13 significantly increased the comet length for all the concentrations tested; however, at pH 12.1, only the two highest concentrations affected the comet length. These results suggested that thallium(I) acetate induces cytotoxic, cytostatic, and clastogenic effects, as well as DNA damage. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 572–580, 2015.

This study has been submitted to the patent's offices at the "University of Granada" and "Fundación Progreso y Salud". Please note that the results of this manuscript have been submitted to patent protection (application number P201630630; title: “Uses of Coenzyme Q biosynthetic proteins”; date:05/16/2016)., Recent clinical trials have shown that in vivo and ex vivo gene therapy strategies can be an option for the treatment of several neurological disorders. Both strategies require efficient and safe vectors to 1) deliver the therapeutic gene directly into the CNS or 2) to genetically modify stem cells that will be used as Trojan horses for the systemic delivery of the therapeutic protein. A group of target diseases for these therapeutic strategies are mitochondrial encephalopathies due to mutations in nuclear DNA genes. In this study, we have developed a lentiviral vector (CCoq9WP) able to overexpress Coq9 mRNA and COQ9 protein in mouse embryonic fibroblasts (MEFs) and hematopoietic progenitor cells (HPCs) from Coq9R239X mice, an animal model of mitochondrial encephalopathy due to primary Coenzyme Q (CoQ) deficiency. Ectopic over-expression of Coq9 in both cell types restored the CoQ biosynthetic pathway and mitochondrial function, improving the fitness of the transduced cells. These results show the potential of the CCoq9WP lentiviral vector as a tool for gene therapy to treat mitochondrial encephalopathies., This work was supported by grants from Ministerio de Economía y Competitividad (Spain) and the European Regional Development Fund (ERDF) from the European Union, to LCL through the research grants SAF2013-47761-R and SAF2015-65786-R; by Fondo de Investigaciones Sanitarias ISCIII (Spain) and the European Regional Development Fund (ERDF) from the European Union through the research grants PI12/01097 and ISCIII Red de Terapia Celular TerCel RD12/0019/0006 to FM; by the Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía-FEDER/Fondo de Cohesion Europeo (FSE) de Andalucía through the research grants P10-CTS-6133 to LCL; P09-CTS-04532, PI-57069, PI-0001/2009 and PAIDI-Bio-326 to F.M.; PI-0160/2012 to KB and PI-0407/2012 to MC; by the NIH through the research P01HD080642 to LCL and by the foundation “todos somos raros, todos somos únicos” to LCL. LCL is supported by the ‘Ramón y Cajal’ National Programme, Ministerio de Economía y Competitividad, Spain (RYC-2011-07643).

15 pages, Ready-to-eat seafood is one of the most important vehicles of foodborne illness in high-income countries, in large part due to a preference for minimally processed and natural foods. A number of hazards potentially affecting ready-to-eat seafood are reviewed within the framework “from sea-to-fork.” Thus, bioaccumulation of pathogenic bacteria and viruses in bivalves to be eaten raw and the presence of helminth parasites in fish flesh are selected as outstanding cases of environmental hazards. However, the safety of ready-to-eat seafood is majorly determined after fishing/harvesting by conditions imposed during handling, processing, distribution, and storage, which can make outgrowth of pathogenic bacteria or toxin formation possible. Postharvest contamination with Listeria monocytogenes and scombrotoxin poisoning are given particular attention

The organoleptic quality of wine distillates depends on raw materials and the distillation process. Previous work has shown that rectification columns in batch distillation with fixed reflux rate are useful to obtain distillates or distillate fractions with enhanced organoleptic characteristics. This study explores variable reflux rate operating strategies to increase the levels of terpenic compounds in specific distillate fractions to emphasize its floral aroma. Based on chemical and sensory analyses, two distillate heart sub-fractions obtained with the best operating strategy found, were compared with a distillate obtained in a traditional alembic. Results have shown that a drastic reduction of the reflux rate at an early stage of the heart cut produced a distillate heart sub-fraction with a higher concentration of terpenic compounds and lower levels of negative aroma compounds. Therefore, this sub-fraction presented a much more noticeable floral aroma than the distillate obtained with a traditional alembic.

Marmajuelo and Malvasia are two white grape varieties grown in Spain (Canary Islands), the former only in the Canary Islands, while the latter is a variety widely spread throughout the world. At the present time, the oenological potential of these varieties grown in the Canaries has not yet been studied. Aroma precursors in musts and skins, and free volatiles in wines were determined in samples of both varieties. Aroma precursors of must and skins were isolated by absorption on XAD-2 resin, and the aglycone liberated by means of acid hydrolysis. Free volatiles from wines and from aroma precursors were extracted with dichloromethane and then analysed by GC–MS. The analysis of glycosidic aroma precursors showed that Malvasia variety presented higher contents of terpenes in grapes than those of Marmajuelo variety. In addition, some precursors of benzenic compounds presented higher contents in the musts of Malvasia with respect to those in the musts of Marmajuelo. The main difference in wine volatile composition was that cis-3-hexen-1-ol, ethyl acetate and γ-nonalactone compounds showed a significantly higher mean content in Malvasia wines than in Marmajuelo wines. Among the aroma precursors analysed, only α-terpineol, linalool oxides, 4-allyl-2,6-dimethoxyphenol, 2-methoxy-4-vinylphenol, 4-hydroxybenzaldehyde, vanillin and benzyl alcohol showed contents in grapes comparable to the levels observed in wine volatile compounds.

BACKGROUND: The aim of this study was to evaluate the effect of the whole non-volatile wine matrix composition on the volatility of typical wine aroma compounds by comparing the slopes of regression lines of five deodorised and reconstituted wines with the slopes calculated for the same compounds in a control wine with no matrix effect. RESULTS: The main effect observed was a reduction in the slopes, or a retention effect, that was largest for the reconstituted sparkling wine, which showed between 11 and 69% lower slopes than the control wine. In addition, an increase in the slopes, or a ‘salting-out’ effect, in the most compositionally complex reconstituted aged-red and sweet wines was also noticed for some volatiles with a very low boiling point or a low hydrophobic constant value. CONCLUSION: This study has shown that the non-volatile composition of wines strongly affects the volatility of wine aroma compounds. In addition, the aroma chemical class, in particular its physicochemical properties (volatility and hydrophobicity), strongly influences this behaviour. On the basis of these results, many odour threshold values calculated in simple hydroalcoholic solutions and usually employed to evaluate the odour importance of specific volatile compounds may have been over- or underestimated. Copyright © 2011 Society of Chemical Industry

Listan blanco is the major grape variety of the Canary Islands. Aroma precursors in musts and free volatiles in wines and their variations due to the skin contact process (10 °C and 0–12 h of maceration) were determined in samples of the Listan blanco grape variety. Aroma precursors of must were isolated by absorption on XAD-2 resin and the aglycone liberated by means of acid hydrolysis. Free volatiles from wines and from aroma precursors were extracted with dichloromethane and then analysed by GC-MS. The results of two consecutive vintages show that only aroma precursors of some terpenes and phenols may affect the final wine aroma. However, the majority of the free compounds of the wines did not present differences in content that could be related to the skin contact process.

9 páginas, 7 tablas, 4 figuras, Hake (Merluccius merluccius) from the Galician inshore fishing fleet, has been used to study the effectiveness of sterile and ozonized water in the conservation of fresh fish. This water was used to wash the fish and to manufacture ice in flakes (Petfrost system). The fish is stored refrigerated in the holds of the boats for a period of up to 18 days. The fish samples came from five samples made at 17, 14, 12, 8 and 3 days from their capture to their arrival to port. Later, once on shore, they were kept refrigerated up 12 days at 2 C. The results of this new processing were compared with those obtained by the traditional method, which consists of using only sea water for the washing and the manufacture of the ice. The results obtained from the study of microbiological, chemical and sensorial variables indicate a greater stability and quality of the hake, as compared with the traditional method, when the new treatment is applied. The study of the five hake samples, from different dates after capture, demonstrated that hake treated with the combined Petfrost system was, in all cases, less deteriorated than the control. The Petfrost hake stored in the boat for 12, 8 and 3 days, once on shore, could last one week conserved in a refrigerated state without deteriorating to the level of unacceptability. For the same conditions, only the control sample with three days of storage on board would be acceptable., This research was supported by Empresa Peter Taboada (Pontevedra-Spain) and by the Xunta de Galicia, project (PGIDIT04TAL029E).

The pistachio (Pistacia vera L.) nut is one of the most widely consumed edible nuts in the world. However, it is the roasting process that makes the pistachio commercially viable and valuable as it serves as the key step to improving the nut’s hallmark sensory characteristics including flavor, color, and texture. Consequently, the present study explores the effects of the single-roasting and double-roasting process on the pistachio’s chemical composition, specifically aroma-active compounds, polyphenols, and lipids. Results showed the total polyphenol content of increased with the roasting treatment; however, not all phenolic compounds demonstrated this behavior. With regard to the aroma and aroma-active compounds, the results indicated that roasting process results in the development of characteristics and pleasant aroma of pistachio samples due to the Maillard reaction. With regard to lipids, the pistachio roasting treatment reduced the concentration of CN38 diacylglycerides while increasing the amount of elaidic acid., J.J.R.B. acknowledges the postdoctoral fellowship for the visiting scientists program, The Scientific and Technological Research Council of Turkey (TUBITAK-BIDEB, no: 2221).

4 páginas, 4 figuras, 2 tablas, The objective of this study was the development of a method for the quantification of free fatty acids (FFA) using less aggressive reactants against the handler and the environment than those used in the classic method of Lowry and Tinsley. The modified procedure is a variation of the Lowry and Tinsley method employing cyclohexane in place of benzene. The use of benzene is prohibited in certain work processes and laboratories, and the competent authority in each country is actively promoting research into harmless or less harmful products that could replace benzene. A comparison with the traditional AOCS titration method for oil analysis was performed. FFA content in mackerel frozen at −10 °C was measured according to the three methods over a 12 month period. The results showed similar values, and good correlations were obtained, This research was supported by the Interministerial Commission of Science and Technology (CICYT) during the Research Project AGL2001-1355.

8 páginas, 3 tablas, 5 figuras, Gram-negative bacteria aremainly responsible for spoilage of refrigerated fish. Nevertheless, to preserve refrigerated fresh fish no additives are permitted and only packaging as in a modified atmosphere can be used. Despite the fact that the present-day application of nisin has been extended to dairy and meat products, its ineffectiveness against Gram-negative bacteria complicates application to fresh fish unless combined with other additives such as chelators. With this aim, agents that increase the permeability of the membrane and facilitate the diffusion of many hydrophobic antimicrobial agents were screened for their combined activity with nisin against different genera of Gram-negative bacteria. Quantification of the synergistic effects has shown sodium hexamethaphosphate (SMP) and ethylenediaminetetraacetic acid (EDTA) were themost effective. Further studies were done on the combined effects of nisin, SMP and CO2 in the preservation of fresh fish. A factorial experimental design was used to determine synergism between these variables. Logarithmic values of total viable counts and total volatile bases after 12 days of storage were described by empirical equations. Analysis of the results showed a marked effect of CO2 in decreasing both variables. Whereas CO2 interacted positively with nisin and SMP, a non-significant interaction was observed between nisin and SMP. It is concluded that CO2 interacts readily with SMP, and may offer an additional advantage for CO2-rich atmospheres in food preservation.

6 páginas, 1 tabla, 5 figuras, The aim of the present study was to design methods for the digestion of fish proteins from processing wastes, leading to new possibilities for little-used species or those generating a significant volume of residues. Residues of rayfish (Raja clavata) were used for the solubilisation of protein by hydrolysis treatment. The kinetics of hydrolysis was studied using rayfish enzymes, either by autolysis of the protein in a triturate of the raw material or by application of a multi-enzyme preparation previously extracted from the viscera of the species. Their effectiveness was compared with that of two commercial enzymes, papain and pepsin. Optimum conditions of hydrolysis and enzymatic activity for digestion with rayfish enzymes were ascertained. The yield of material and the efficiency of digestion in each of the hydrolysis processes are reported, This work was supported by Xunta of Galicia, project PGIDT PIN004.

Vanadium has been considered an aneuploidogen; however, there is controversial information about the clastogenic effects of vanadium compounds. In this study, the genotoxicity of vanadium(IV) tetraoxide (V(2)O(4)) was evaluated in human cultured lymphocytes and leukocytes using the mitotic index (MI), the replicative index (RI), chromosome aberrations (CA), sister chromatid exchanges (SCE), satellite associations (SA) and the single cell gel electrophoresis (SCGE) assay. This chemical induced a clear dose-response in MI inhibitions and modifications in the RI. In the CA, including breaks and exchanges and in the SCE, a significant increase appeared in the treated group compared with the controls. The SA test did not reveal an important difference. For the detection of genotoxic properties of vanadium(IV) using the SCGE assay, the 2 h evaluation period was not long enough for the chemical to enter the cell. These results indicate that vanadium(IV) tetraoxide is capable of inducing cytotoxic and cytostatic effects and chromosomal damage.

5 páginas, 4 tablas, 2 figuras, The effects of lauric acid on pre-cooked products derived from minced cod or shrimp tails stored in the refrigerated state were studied. Lauric acid was employed either with or without modified atmosphere packaging (MAP:50% CO2:50% N2). Synergism between lauric acid and MAP on bacterial growth kinetics was found in pre-cooked minced fish products but not in precooked shrimp tail products. Sensory properties of both products received the highest scores when treated with lauric acid and packed under a modified atmosphere. Only samples subjected to combined treatment were commercially acceptable after 1 month of storage., This work was supported by CICYT (Inter-ministerial Committee of Science and Technology, project PETRI 95-0324-OP).

Orujo is a traditional alcoholic beverage produced in Galicia (northwest Spain) from distillation of grape pomace, a byproduct of the winemaking industry. In this study, the effect of the distillation system (copper charentais alembic versus packed column) and the yeast strain (native yeast L1 versus commercial yeast L2) on the chemical and sensory characteristics of orujo obtained from Albariño (Vitis vinifera L.) grape pomace has been analyzed. Principal component analysis, with two components explaining 74% of the variance, is able to clearly differentiate the distillates according to distillation system and yeast strain. Principal component 1, mainly defined by C6-C12 esters, isoamyl octanoate, and methanol, differentiates L1 from L2 distillates. In turn, principal component 2, mainly defined by linear alcohols, linalool, and 1-hexenol, differentiates alembic from packed column distillates. In addition, an aroma descriptive test reveals that the distillate obtained with a packed column from a pomace fermented with L1 presented the highest positive general impression, which is associated with the highest fruity and smallest solvent aroma scores. Moreover, chemical analysis shows that use of a packed column increases average ethanol recovery by 12%, increases the concentration of C6-C12 esters by 25%, and reduces the concentration of higher alcohols by 21%. In turn, L2 yeast obtained lower scores in the alembic distillates aroma profile. In addition, with L1, 9% higher ethanol yields were achieved, and L2 distillates contained 34%-40% more methanol than L1 distillates.

12 pages, 5 figures, 2 tables, The present study was aimed to evaluate the potential of essential oils to remove the foodborne pathogen Staphylococcus aureus from food-processing facilities. The effectiveness of 19 essential oils against planktonic cells of S. aureus was firstly assessed by minimal inhibitory concentration. Planktonic cells showed a wide variability in resistance to essential oils, with thyme oil as the most effective, followed by lemongrass oil and then vetiver oil. The eight essential oils most effective against planktonic cells were subsequently tested against 48-h-old biofilms formed on stainless steel. All essential oils reduced significantly (p < 0.01) the number of viable biofilm cells, but none of them could remove biofilms completely. Thyme and patchouli oils were the most effective, but high concentrations were needed to achieve logarithmic reductions over 4 log CFU/cm(2) after 30 min exposure. Alternatively, the use of sub-lethal doses of thyme oil allowed to slow down biofilm formation and to enhance the efficiency of thyme oil and benzalkonium chloride against biofilms. However, some cellular adaptation to thyme oil was detected. Therefore, essential oil-based treatments should be based on the rotation and combination of different essential oils or with other biocides to prevent the emergence of antimicrobial-resistant strains., This work was financially supported by the Xunta de Galicia (PGIDIT 07 TAL 014402PR). Author DVS was supported by a research grant (JAE Program) by CSIC.

The impact of the addition of glutathione-enriched Inactive dry yeast preparations (g-IDYs) on the stability of some typical wine terpenes (linalool, α-terpineol, β-citronellol, and nerol) stored under accelerated oxidative conditions was evaluated in model wines. Additionally, the effects of a second type of IDY preparation with a different claim (fermentative nutrient) and the sole addition of commercial glutathione into the model wines were also assessed. Model wines were spiked with the low molecular weight fraction (, This work was funded by the MINECO (AGL2012-04172-C02-01) and CONSOLIDER INGENIO 2010 (FUN-CFOOD, CSD2007-063, Projects) and by Agrovin, S.A. (I+D 20132446 Contract). J.J.R.B. thanks CSIC for the JAE-doc contract.

10.1111/ijfs.12402 The bentonite use to remove proteins from white wine is a widespread practice that prevents protein haze formation after bottling. However, an excess of bentonite can have negative effects on both the aromatic profile of young white wines and the quality of the foam of sparkling wines. Therefore, the optimisation of bentonite amount to be used and the moment of its application during winemaking to minimise wine quality losses are of great interest for winemakers. This paper analyses how applying an equal bentonite dose at different stages (must clarification; beginning, middle and end of fermentation) on two scales (industrial and pilot) affects the protein content and stability, physical¿chemical characteristics, aromatic profile and foam quality of the obtained wines. No important differences in the oenological parameters were observed between industrial and pilot scales, whereas the scale of the experimental treatments affected protein stability, aroma composition and foam quality of the wines.

The potential of winemaking grape pomace by-products as a source of glycosidic aroma precursors that under enzymatic hydrolysis might release aroma compounds has been evaluated. Two different extraction methodologies, liquid-liquid and pressurized liquid extraction (LLE and PLE) were employed. Solid phase extraction (SPE)-GC-MS analysis of the hydrolyzed LLE glycosidic extract revealed 22 aroma compounds belonging to different chemical families (terpenes, C13 norisoprenoids, vanillines, etc.). Response surface methodology was employed to study the effect of the most significant PLE experimental variables (temperature and solvent composition) on the extraction of aromatic aglycones. The parameters of the model were estimated by multiple linear regressions. Most of the aroma compounds showed an adequate fit to the calculated model (18 compounds from 22 with R 2 > 0.8). The application of the optimized PLE conditions (50 % of ethanol in the hydroalcoholic solution) and 90 °C showed higher extraction yield of aglycones when comparing with the extraction yield obtained by LLE. © 2013 Springer Science+Business Media New York., This work has been funded by the CSIC INTRAMURAL Project 201070I036. CMG and JJRB thank the CSIC for their respective research contracts.

7 páginas, 2 tablas, 5 figuras, Adding maltodextrins to minced blue whiting muscle inhibited formaldehyde production during storage at −10 and −20 °C. Sucrose, however, was effective only at −20 °C. These results were not proportional to the difference between the storage temperature and the ice-melting onset (Tm‘), and freeze−concentration had to be considered. In the face of serious limitations to do this, resource was made to the state diagram for the sucrose−water binary system and the percentage variation of the ice-melting endotherm area of the different samples. A higher Tm‘ and a lower freeze−concentration would account for the inhibiting effects of maltodextrins, whereas sucrose, despite diminishing Tm‘, had an effect nearly as great as maltodextrins at −20 °C but had hardly any at −10 °C. The reason for this seems to lie in a lower freeze−concentration of solutes in the unfrozen water phase. Similarly, the differences found between sucrose and maltodextrins, as well as among maltodextrins, were also explained in terms of Tm‘ and freeze−concentration., This work was carried out with the financial support of the Interministerial Commission for Science and Technology (CICYT Research Project ALI97-0589).

12 páginas, 7 tablas, 7 figuras, The production of formaldehyde in frozen-stored minced blue whiting muscle was described by a rectangular hyperbolic model, and the effectiveness of each cryostabilizer is discussed in terms of its parameters. The maltodextrins assayed noticeably inhibited formaldehyde production, this effect being greater at −20 °C than at −10 °C. Sucrose was only effective at −20 °C. It seems that these compounds act by restricting molecular diffusion. The effect of each cryostabilizer on formaldehyde binding was closely regulated by its effect on production. This is discussed in terms of the binding equation parameters. The binding of formaldehyde during frozen storage was dependent on protein rearrangements leading to reactive groups becoming available. The constraints of cryostabilizers on molecular diffusion reduced the exposure of these groups. Consequently, the interpretation of formaldehyde reactivity was biased, leading to conclusions different from those that would be obtained from a study done under standard conditions., This work was carried out with the financial support of the Interministerial Commission for Science and Technology (CICYT) within Research Project ALI97-0589.

9 páginas, 3 tablas, 5 figuras, Adhesion and biofilm-forming ability of twenty six S. aureus strains previously isolated from fishery products on stainless steel was assessed. All strains reached counts higher than 104 CFU/cm2 after 5 h at 25 °C. Most strains also showed a biofilm-forming ability higher than S. aureus ATCC 6538 – reference strain in bactericidal standard tests – by crystal violet staining. In addition, it seems that food-processing could have produced a selective pressure and strains with a high biofilm-forming ability were more likely found in highly handled and processed products. The efficacy of the industrial disinfectants benzalkonium chloride (BAC), sodium hypochlorite (NaClO) and peracetic acid (PAA) against biofilms and planktonic counterparts was also examined in terms of minimum biofilm eradication concentration (MBEC) and minimum bactericidal concentration (MBC), respectively. Biofilms showed an antimicrobial resistance higher than planktonic cells in all cases. However, no correlation was found between MBEC and MBC, likely due to differences in biofilm extracellular matrix (composition, content and architecture) between strains. BAC resistance increased as biofilms aged. Generally, biofilm formation seemed to attenuate the effect of low temperatures on BAC resistance. PAA was found to be most effective against both biofilms and planktonic cells, followed by NaClO and BAC. Resistance did not follow the same order for each biocide, which remarks the need of using a wide collection of strains in standard tests of bactericidal activity to ensure a proper application of disinfectants. Doses recommended by manufacturers for BAC, PAA and NaClO to disinfect food-contact surfaces were lower than doses for complete biofilm removal (i.e. MBEC) under some environmental conditions common in the food industry, which questions bactericidal standard tests and promotes the search for new strategies for biofilm removal., This work was financially supported by Xunta de Galicia (PGIDIT 07 TAL 014402PR). Author DVS and PSI were supported by two research grants (JAE Programme) by CSIC. Author JJRH was partially supported by the Ramón y Cajal Programme (co-financed by the European Social 5 Fund).

The addition of glycosidic aroma precursors isolated from grapes to reinforce the aroma profile of a dealcoholised white wine has been investigated. Moreover, the use of oenological glycosidases and the effect of storage (30. days) on the evolution of the released aglycones were evaluated. Four types of dealcoholised wines: control (CTR), control with enzyme addition (CTR-E), wine with added aroma precursors (PREC) and wine with enzyme and aroma precursors (PREC-E) were prepared. The analysis of free volatile compounds by HS-SPME-GC-MS and the application of multivariate statistical analysis confirmed differences in the volatile profile between CTR and PREC wines. By applying aroma dilution and olfactometry analysis (AEDA-GC-O), 20 odour notes were detected. The highest dilution factors eliciting floral like odour were found in PREC wines and identified as linalool, geraniol and β-phenylethyl alcohol. Sensory descriptive analysis confirmed higher intensity in Muscat and floral attributes in these wines, which open the possibility to new technological application based on using aroma precursors to enhance the aroma characteristics of wines with low aroma intensity. © 2013 Elsevier Ltd., This work has been funded by CSIC INTRAMURAL Project 201070I036. JJRB and CMG thank CSIC for their respective research contracts. Dr. Selli thanks The Council of Higher Education (YOK) of Turkey for financial support which allowed him to join this research in Spain.

5 páginas, 3 figuras, Salmon slices (Salmo salar) were packed under CO2 and stored in a chill room at 2±1°C for 3 weeks. A study was carried out on the effect of CO2 atmosphere on bacterial growth as well as on chemical deterioration (pH, total volatile bases, (TVB), trimethylamine (TMA), lipid oxidation) and sensory features (exudation, raw fish odour, cooked fish flavour). Results were compared with a control stored in air. Salmon slices stored under CO2 had a shelf-life of nearly twice as long as those in air, having lower bacterial counts, pH, TMA and TVB, as well as improved sensory features after 18 days at 2±1°C. Exudation was not significantly different between control and CO2-stored samples after 10 days ice storage. Exudate values extended from 1 to 2% for CO2-stored samples after 10 and 20 days storage, respectively. Salmon slices can be stored under CO2 at 2±1°C for about 18 days, with no substantial loss of quality. Shelf-life can vary depending upon the state of fish, handling practices, initial bacterial load and storage temperature., support of Freiremar SA (Vigo-Spain) and of the Comisih Interministerial de Ciencia y Tecnologia (CICYT) within the Research Project ALI93-0714-C02-01

Laticifer cells are specialized plant cells that synthesize and accumulate latex. Studies on laticifers have lagged behind in recent years, and data regarding the functional role of laticifers and their fitness benefit still remain elusive. Laticifer differentiation and its impact on plant growth and development also remain to be investigated. Here, cellular, molecular, and genetic tools were developed to examine the distribution, differentiation, ontogeny, and other characteristic features, as well as the potential developmental role of laticifer cells in the latex-bearing plant Euphorbia lathyris. The organization of the laticiferous system within the E. lathyris plant body is reported, emerging as a single elongated and branched coenocytic cell, constituting the largest cell type existing in plants. We also report the ontogeny and organization of laticifer cells in the embryo and the identification of a laticifer-associated gene expression pattern. Moreover, the identification of laticifer- and latex-deficient mutants (pil mutants) allowed for the identification of distinct loci regulating laticifer differentiation, growth, and metabolic activity. Additionally, pil mutants revealed that laticifer cells appear nonessential for plant growth and development, thus pointing toward their importance, instead, for specific ecophysiological adaptations of latex-bearing plants in natural environments.

Biofilms are a common cause of food contamination with undesirable bacteria, such as pathogenic bacteria. Staphylococcus aureus is one of the major bacteria causing food-borne diseases in humans. A study designed to determine the presence of S. aureus on food contact surfaces in dairy, meat, and seafood environments and to identify coexisting microbiota has therefore been carried out. A total of 442 samples were collected, and the presence of S. aureus was confirmed in 6.1% of samples. Sixty-three S. aureus isolates were recovered and typed by random amplification of polymorphic DNA (RAPD). Profiles were clustered into four groups which were related to specific food environments. All isolates harbored some potential virulence factors such as enterotoxin production genes, biofilm formation-associated genes, antibiotic resistance, or lysogeny. PCR-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprints of bacterial communities coexisting with S. aureus revealed the presence of bacteria either involved in food spoilage or of concern for food safety in all food environments. Food industry surfaces could thus be a reservoir for S. aureus forming complex communities with undesirable bacteria in multispecies biofilms. Uneven microbiological conditions were found in each food sector, which indicates the need to improve hygienic conditions in food processing facilities, particularly the removal of bacterial biofilms, to enhance the safety of food products.

5 páginas, 4 tablas, A new method to obtain benzalkonium chloride (BAC) adapted L. monocytogenes cells was developed. A factorial design was used to assess the effects of the inoculum size and BAC concentration on the adaptation (measured in terms of lethal dose 50 –LD50–) of 6 strains of Listeria monocytogenes after only one exposure. The proposed method could be applied successfully in the L. monocytogenes strains with higher adaptive capacity to BAC. In those cases, a significant empirical equation was obtained showing a positive effect of the inoculum size and a positive interaction between the effects of BAC and inoculum size on the level of adaptation achieved. However, a slight negative effect of BAC, due to the biocide, was also significant. The proposed method improves the classical method based on successive stationary phase cultures in sublethal BAC concentrations because it is less time-consuming and more effective. For the laboratory strain L. monocytogenes 5873, by applying the new procedure it was possible to increase BAC-adaptation 3.69-fold in only 33 h, whereas using the classical procedure 2.61-fold of increase was reached after 5 days. Moreover, with the new method, the maximum level of adaptation was determined for all the strains reaching surprisingly almost the same concentration of BAC (mg/l) for 5 out 6 strains. Thus, a good reference for establishing the effective concentrations of biocides to ensure the maximum level of adaptation was also determined., This work was financed by the Spanish Ministry of Science and Technology (project AGL2006-01483/ALI) and by the Xunta of Galicia (PGIDIT06TAL40201PR).