Suchergebnisse

In this work, an advanced approach combining small angle X-ray scattering (SAXS) experiments, rheology and confocal laser scanning microscopy was used to explain the different emulsification mechanisms of three pectin sources (pectin extracted from watermelon rind -WRP- and commercial citrus -CP- and apple pectin -AP). Very interestingly, three different emulsification mechanisms were identified, related to the structure and composition of the pectin extracts. WRP had significantly greater emulsifying capacity than commercial CP and AP. This enhanced emulsification ability was mainly ascribed to a combination of its relatively high protein content (mainly acting as the surface-active material), combined with the presence of longer sugar side chains in pectin, further contributing to stabilizing the oil droplets in the emulsions. All these structural features resulted in a reduction in the mean droplet size as the concentration increased, thus, hindering flocculation and coalescence during the short-term storage conditions at 4 °C. In contrast, AP had the lowest emulsification capacity, which was only related to its viscosifying effect (provided by its greater Mw), while CP, having the greatest homogalacturonan content, greatest linearity and a more balanced hydrophilic/hydrophobic character (reflected in the degree of esterification), was able to form a better adsorbed layer at the o/w interphase, although it could not avoid flocculation and creaming at low pectin concentration during refrigerated storage. ; This work was funded by the grant RTI-2018-094268-B-C22 (MCI/AEI/FEDER, EU). Mendez D. A. is supported by the Administrative Department of Science, Technology and Innovation (Colciencias) of the Colombian Government (783–2017). M. J. Fabra and A. Martinez-Abad are recipients of Ramon y Cajal (RYC-2014-158) and Juan de la Cierva (IJDC-2017-31255), respectively, from the Spanish Ministry of Economy, Industry and Competitiveness. ; Peer reviewed

18 p.-4 fig. ; We report the construction of a plasmid vector designed for regulated gene expression in Streptococcus pneumoniae. The new vector, pLS1ROM, is based on the replicon of the streptococcal promiscuous rolling circle replication (RCR) plasmid pMV158. We inserted the controllable promoter PM of the S. pneumoniaemalMP operon, followed by a multi-cloning site sequence aimed to facilitate the insertion of target genes. The expression from PM is negatively regulated by the transcriptional repressor MalR, which is released from the DNA operator sequence by growing the cells in maltose-containing media. To get a highly regulated expression of the target gene, MalR was provided in cis by inserting the malR gene under control of the constitutive Ptet promoter, which in pMV158 directs expression of the tetL gene. To test the functionality of the system, we cloned the reporter gene gfp from Aequorea victoria, encoding the green fluorescent protein (GFP). Pneumococcal cells harboring the recombinant plasmid rendered GFP fluorescence in a maltose-dependent mode with undetectable background levels in the absence of the inducer. The new vector, pLS1ROM, exhibits full structural and segregational stability and constitutes a valuable tool for genetic manipulation and regulated gene expression in S. pneumoniae ; This study was supported by the Spanish Ministerio de Ciencia e Innovación (Grants CSD2008-00013, INTERMODS to ME; BFU2007-63575 and BFU2010-19597, PNEUMOTALK to GdS) and the European Union (Grant EU-CP223111, CAREPNEUMO to ME) ; Peer reviewed

This work reports on the production and characterization of agar-based extracts from the seaweed Gelidium sesquipedale by means of simple protocols based on hot water and sonication treatments. The combination of sonication with the hot water treatment reduced 4-fold the extraction time without significantly affecting the extraction yield (ca. 10–12%) and the extracts' properties. Apart from agar, the extracts contained proteins, polyphenols and minerals, which conferred them high antioxidant capacity and led to the production of brownish softer gels. The application of an alkali pre-treatment yielded almost pure agars, with higher molecular weights and crystallinities than commercial agar, resulting in stiffer gels. However, the partial digestion of agar by the alkali led to low extraction yields (ca. 2–3%). These results show the efficiency of the combined heat and sonication method to generate cost-effective agar-based extracts with potential applications within the food industry. ; This work was financially supported by the "Agencia Estatal de Investigación" and co-funded by the European Union's Horizon 2020 research and innovation programme (ERA-Net SUSFOOD2). Marta Martinez-Sanz is recipient of a Juan de la Cierva (IJCI-2015-23389) contract from the Spanish Ministry of Economy, Industry and Competitiveness.

Seaweed residues from Alaria esculenta, Saccharina latissima and Ascophyllum nodosum after alginate extraction have been valorized to produce cellulose-based fractions with different purification degrees. The residues were mainly composed of carbohydrates (35–57%) and proteins (12–37%), Alaria and Saccharina being richer in cellulose and Ascophyllum richer in fucoidan. The lower cellulose content in the latter made it unsuitable for the extraction of cellulosic fractions. Self-supporting films were obtained from the cellulosic fractions from Saccharina and Alaria residues. While the higher cellulose purity films presented more desirable characteristics in terms of mechanical properties (with elastic moduli of ca. 5–7 GPa and elongation values of ca. 3–5%) and visual appearance, the presence of non-cellulosic components in the films from less purified fractions reduced their water sensitivity and promoted greater water barrier (with water permeability values of ca. 4–6 kg·m/s·m2·Pa). These results point towards the potential of a simple alkaline extraction to generate cellulose-based films from seaweed residuals with the best compromise between functional properties and economical and environmental efficiency. ; This work was financially supported by the "Agencia Estatal de Investigación" (PCI2018-092886 Grant) and co-funded by the European Union's Horizon 2020 research and innovation programme (ERA-Net SUSFOOD2) and the RTI2018-094408-J-I00 project (MCIU/AEI/FEDER,UE). ; Peer reviewed

The objective of this work was to investigate whether the use of unpurified agar-based fractions extracted from the seaweed Gelidium as microencapsulation matrices has an impact on probiotic protection during storage. Therefore, unpurified and pure agar and agarose-based microcapsules were produced through emulsification/internal gelation for the protection of Bifidobacterium pseudocatenulatum CECT 7765. Initially, agarose-based formulations with other biopolymers were evaluated, given the excellent oxygen barrier properties of this polysaccharide. The optimal combination in terms of probiotic protection was selected for further experiments and this agarose-based formulation was compared with microcapsules produced using both pure and unpurified agar-based fractions. The presence of other compounds (mainly proteins and polyphenols) in the unpurified agar fractions significantly improved the viability of these sensitive probiotic bacteria both at ambient and refrigerated storage conditions. Furthermore, the presence of impurities allowed the increase of solids content in the formulation giving raise to stronger gel particles, which could contribute to limited oxygen diffusion, thus, partly explaining the improved protection. Therefore, this work demonstrates the potential of more cost-effective less purified carbohydrate-based fractions for probiotic protection. ; This work was financially supported by the "Agencia Estatal de Investigación" and co-funded by the European Union's Horizon 2020 research and innovation programme (ERA-Net SUSFOOD2) and the European Union's Seventh Framework Program under the grant agreement no 613979 (MyNewGut). Marta Martinez-Sanz, Maria José Fabra and Laura G. Gómez-Mascaraque are recipients of a Juan de la Cierva (IJCI-2015-23389), Ramon y Cajal (RYC-2014-158) and predoctoral (BES-2013-065883) contracts, respectively, from the Spanish Ministry of Economy, Industry and Competitiveness. ; Peer reviewed

Posidonia oceanica waste biomass has been valorised to produce extracts by means of different methodologies and their bioactive properties have been evaluated. Water-based extracts were produced using ultrasound-assisted and hot water methods and classified according to their ethanol-affinity (E1: ethanol soluble; E2: non-soluble). Moreover, a conventional protocol with organic solvents was applied, yielding E3 extracts. Compositional and structural characterization confirmed that while E1 and E3 extracts were mainly composed of minerals and lipids, respectively, E2 extracts were a mixture of minerals, proteins and carbohydrates. All the extracts showed remarkably high antioxidant capacity, which was not only related to phenolic compounds but also to the presence of proteins and polysaccharides. All E2 and E3 extracts inhibited the growth of several foodborne fungi, while only E3 extracts decreased substantially the infectivity of feline calicivirus and murine norovirus. These results show the potential of P. oceanica waste biomass for the production of bioactive extracts. ; This work was financially supported by the project GV/2018//149, the "Agencia Estatal de Investigación" and cofunded by the European Union's Horizon 2020 research and innovation programme (ERA-Net SUSFOOD2). Marta Martinez-Sanz is recipient of a Juan de la Cierva (IJCI-2015-23389) contract from the Spanish Ministry of Economy, Industry and Competitiveness.

IntroductionTraditional screening system focus on classic risk factors "lost" a substantial proportion of HIV‐infected patients. Several organizations such as CDC or USPS Task Force favour universal screening for HIV infection for good cost‐effectiveness profile. In a previous study prevalence of HIV infection in patients attending our infectious diseases department was high (5.4%).ObjectiveTo determine prevalence of HIV infection in patients aged 20–55 years in primary care (PC).Material and MethodsA propsective observational study was undertaken between February and June 2013. We performed a screening of HIV infection type "Opt‐out" (offering voluntary rejection) in 4 PC centers (32 Physicians) in San Juan‐Alicante. Sample size (n=318) for a prevalence of 1% and a confidence level of 97% was calculated. Nevertheless, other PC physician not recruiting patients performed HIV testing according clinical risk factors.ResultsHIV testing was offered to 508 patients. Mean age 38.9±10 years (58.5% female). Overall, 430 (83.8%) agreed to participate. Finally, 368 patients (71.7% of total) were tested for HIV. No patient had a positive result (100% ELISA HIV negative). However, following clinical practice, 3 patients were diagnosed of HIV in the same period by non‐recruiting physicians. In 2 cases, serology was performed at the patient's request and in one case by constitutional syndrome. The 3 patients were MSM.Conclusions1) In our study, we detected no new cases of HIV infection through universal screening. 2) Our screened population could be lower‐risk because of high percentage of women included (58.5%). 3) Performing HIV opt‐in screening (clinical practice), we detected 3 cases in the same period, all having HIV risk factors (MSM). 4) These results suggest that opt‐out screening should be developed in high‐risk populations. It is still to be determined what is the best screening strategy in low‐risk populations such as ours.

AbstractIntegrative passive samplers, such as DGT (Diffusive Gradients in Thin-films), are identified in European Technical Guidance Documents as promising tools to improve the quality of the assessment, in the context of the WFD (EU Water Framework Directive). However, DGT results cannot yet be used directly in a regulatory framework to assess the chemical status of water bodies, as DGT labile concentrations cannot be directly compared to the metal AA-EQSmarine water (Annual Average Environmental Quality Standard) established by the WFD, which are defined in the dissolved concentration. Therefore, prior to using DGT results in a regulatory context, for cadmium, nickel and lead, an adaptation of existing AA-EQSmarine water for DGTs should be pursued, ensuring at least the same level of protection. In this sense, in the framework of the MONITOOL project, a robust database of dissolved and labile metal concentrations in transitional and coastal waters, for adapting the existing AA-EQSmarine water for DGT technique, was obtained. Building on these results, this study proposes a methodology and provides values and equations for using DGT results for the chemical status assessment of marine waters, by adapting the EQSmarine water to adapted EQSDGT or predicting dissolved concentrations from DGT results. Based on available dataset, a first simulation of "chemical status" assessment per MONITOOL sampling site using DGT measured labile concentrations was carried out and the results were compared to an assessment based on dissolved concentration to check their compliance. These results demonstrate that the use of DGT passive samplers is appropriate for the metal concentrations level encountered in the marine environment. Further work is recommended to test the effectiveness of the methodology proposed in this study under WFD conditions on more sites and to establish common strategy guidelines for the use of DGT passive samplers in monitoring.