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Se in the form of sodium selenite was microencapsulated by spray - drying and added to a food matrix (yogurt) to study the potential improvement of its bioaccessibility. Yogurt samples were also supplemented with Se in free salt form. Se-loaded microparticles were successfully prepared by spray-drying with production yields above 70%. The supplementation of yogurt with Se in the form of free sodium selenite had a low effect on improving the bioaccessibility of this micronutrient (1%). In turn, Se microencapsulation with mannitol or mannitol/gastro-resistant polymer (Eudragit (R)) had a strong impact on bioaccessibility results. After the gastric phase, Se bio-accessibility reached values of 21 and 40% for the microencapsulated formulations, respectively. This percentage rose to 55% at the end of intestinal phase, showing no differences between both formulations. Our results show the relevance of microencapsulation as an effective tool to improve the bioaccessibility of micronutrients when they are used in food supplementation. LA/P/0101/2020 info:eu-repo/semantics/publishedVersion

This study evaluates the influence on body development of doing rhythmic gymnastics in girls from 10 to 17 years of age, the results of certain strength and flexibility abilities, and the trace element status (Ca, Fe, Zn, Cu, Mn, Cr, and Ni). The subjects were divided into three groups: (a) girls who practiced rhythmic gymnastics at a competition level (competition group); (b) girls who practiced this sport at a non-competitive level (training group); and (c) girls who do not practice any sport and with a low level of physical activity (control or sedentary group). Trace element status was determined in hair and urine samples. Results showed that doing rhythmic gymnastics does not alter the normal physical development of muscle mass, and even leads to a decrease in body fat content. Furthermore, better scores in the strength and flexibility test were obtained by the participants of this sports discipline. Statistically significant differences in urine Fe, Cu, and Mn values (p0.05) and in hair Cr, Cu, and Mn values (p0.05) were found between the two rhythmic gymnastics groups and the control group, and were higher in the competition and training groups. A principal component analysis model was performed to evaluate the possibility of cluster formation among the girls. The PCA results revealed a separation between the different groups although the separation was not perfect. PLS-DA was attempted in order to verify whether it was possible to discriminate between the groups included in this study. It was clear that the competition and control ones were very well classified (around 95% of correct predictions) but 20% of the girls belonging to the training group were misclassified as belonging to the competition one.

Books, prints, drawings, watercolours, engravings, as well as all other works of art based on paper, are very susceptible to fungal development. The excreted substances and the fungal structures themselves are often coloured and interfere with the readability of the artefacts, diminishing their artistic and monetary value. In order to direct cleaning methods for specific fungal stains on paper, the colourants (molecules) responsible for those stains need to be assessed. However, the literature regarding fungal stains on paper and colourants produced by those fungi is very dispersed and scarce. Therefore, the main objectives of this work were surveying the most common stains on paper, the colourants present on those stains and the main fungi responsible for these colourants’ production. To achieve these goals, two different but complementary literature reviews were made: one on paper conservation literature, where fungal stains observed on paper cultural heritage are reported; and another survey on the chemical/food/pharmaceutical fields where colourants’ molecules produced by fungi, that can colonise paper cultural heritage, are identified and studied in greater detail. This paper presents the first literature review on this subject. The results show that the fungal genera more frequently related with fungal stains on paper cultural heritage are Aspergillus (29%) and Penicillium (13%). The most common colour of the stains is brown (54%), caused by foxing in most of the cases. However, in the paper conservation literature, no consistent correlation has been observed between stain colour on paper/specific fungal species and colourants/chemical compounds. On the literature review regarding the use of fungal colourants for industrial/commercial purposes, the referred colourants can be mostly classified chemically as carotenoids and polyketides. Biosynthetically, most colourants produced by fungi are polyketide-based and representative classes may include chemical structures such as azaphilones, anthraquinones, hydroxyanthraquinones, naphthoquinones and other structures. From a total of 80 different colourants, the ones mostly produced by paper colonising fungi were polyketide quinones, namely the hydroxyanthraquinoid (HAQN) colourants. This review showed that the most commonly studied colours are yellow and red, followed by orange. The production of these colourants is often associated with the genera Aspergillus sp. and Penicillium sp. which are frequently found on stained paper. Overall, there is no doubt that colourants producing fungi are a serious problem to paper conservators, since there is a great variety of colourants produced by different species of fungi colonising paper. This review catalogues the fungal genera, species and excreted colourants mentioned in the literature as being responsible for staining paper cultural heritage.

Vibrational spectroscopy has long been used in bacterial identification with different levels of taxonomic discrimination but its true potential for intra-species differentiation remains poorly explored. Herein, both transmission Fourier-transform infrared (FTIR) and attenuated total reflectance (ATR)-FTIR spectroscopy are used to analyse E. coli strains that differ solely in their porin expression profile. In this previously unreported approach, the applicability of both FTIR-spectroscopy techniques is compared with the same collection of unique strains. ATR-FTIR spectroscopy proved to reliably distinguish between several E. coli porin mutants with an accuracy not replicated by FTIR in transmission mode (using previously optimized procedures). Further studies should allow the identification of the individual contribution of the single porin channel to the overall bacterial infrared spectrum and of molecular predictive patterns of porin alterations.

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