Highly efficient and reusable CNT supported iron(II) catalyst for microwave assisted alcohol oxidation

The highly efficient eco-friendly synthesis of ketones (yields over 99%) from secondary alcohols is achieved by combination of [FeCl2{eta(3)-HC(pz)(3)}] (pz = pyrazol-1-yl) supported on functionalized multi-walled carbon nanotubes and microwave irradiation, in a solvent-free medium. The carbon homoscorpionate iron(II) complex is the first one of this class to be used as catalyst for the oxidation of alcohols

Sodium butyrate in growing and fattening diets for early-weaned rabbits

[EN] To study the effect of adding coated sodium butyrate (SB) to growing-fattening rabbit diets, 2 trials were conducted. In trial 1, 180 rabbits were housed in pairs and fattened from 23 (weaning) to 63 d of age to evaluate their zootechnical performance. Trial 2 involved 30 rabbits, from 23 to 37 d of age and housed individually in digestibility cages, to evaluate digestibility, caecal fermentative activity and morphology of the intestinal mucosa. In both trials rabbits were randomly divided into 2 groups, each receiving one of the following diets: control diet [CTR, 360 g neutral detergent fibre (NDF) and 170 g crude protein (CP)/kg dry matter (DM)] and SB diet. The SB diet, similar to CTR diet, included coated SB at 5 g/kg by replacement of an identical quantity of wheat. In trial 1, after the first 2 wk, the SB content was reduced from 5 to 3 g/kg. In trial 2, faeces were collected over the last 6 d (32-37 d of age), with rabbits being slaughtered at 37 d of age. Gastric and caecal pH were measured and fermentative activity was determined in caecal contents. Three sections of the small intestine were excised from 20 rabbits (10 per treatment) for microscopic examination of intestinal villi and crypts in the proximal region, central region and distal region. In the first 2 wk after weaning, SB rabbits grew 8% less than their counterparts (P=0.002), but had a better feed conversion ratio (1.58 vs. 1.61; P=0.036). During the whole trial 1 period, SB improved feed conversion (P=0.005) and decreased feed intake (104.1 CTR vs. 98.8 g/d SB; P=0.017). No difference was recorded in daily weight gain (42.7 vs. 42.9 g/d). In both diets, the digestibility of DM, organic matter, energy, CP and NDF were similar. In the 3 intestinal regions of rabbits fed SB diet, crypts were deeper (P<0.05). There were no significant differences in villus height and width between treatments. Pectinase activity was higher (P=0.054) with SB diet, but cellulase and xylanase activity remained unaffected by diet. In our experimental conditions, the addition of SB allowed an improvement in feed conversion.Ribeiro, J.; Gaspar, S.; Pinho, M.; Freire, JPB.; Falcão-E-Cunha, L. (2012). Sodium butyrate in growing and fattening diets for early-weaned rabbits. World Rabbit Science. 20(4):199-207. doi:10.4995/wrs.2012.1233SWORD19920720

Combining urban wastewater treatment with biohydrogen production: An integrated microalgae-based approach

The aim of the present work was the simultaneous treatment of urban wastewater using microalgae and the energetic valorization of the obtained biomass. Chlorella vulgaris (Cv), Scenedesmus obliquus (Sc) and a naturally occurring algal Consortium C (ConsC) were grown in an urban wastewater. The nutrient removals were quite high and the treated water fits the legislation (PT Dec-Lei 236/98) in what concerns the parameters analysed (N, P, COD). After nutrient depletion the microalgae remained two more weeks in the photobioreactor (PBR) under nutritional stress conditions, to induce sugar accumulation (22–43%). The stressed biomass was converted into biohydrogen (bioH2), a clean energy carrier, through dark fermentation by a strain of the bacteria Enterobacter aerogenes. The fermentation kinetics were monitored and fitted to a modified Gompertz model. The highest bioH2 production yield was obtained for S. obliquus (56.8 mL H2/gVS) which was very similar when using the same algae grown in synthetic media

Solvent-Free Microwave Extraction of Thymus mastichina Essential Oil: Influence on Their Chemical Composition and on the Antioxidant and Antimicrobial Activities

This article belongs to the Special Issue Antiradical, Chemopreventive and Antimicrobial Analysis of Bioactive SubstancesSolvent-free microwave extraction (SFME) is a combination of microwave heating and dry distillation performed at atmospheric pressure without the addition of water or organic solvents that has been proposed as a green method for the extraction of essential oils from aromatic and medicinal herbs. In this work, SFME and the conventional techniques of steam distillation (SD) and hydrodistillation (HD) were compared with respect to the extraction and antioxidant and antimicrobial activities of Thymus mastichina essential oil. The main constituent of essential oils obtained using different methods was 1,8-cineole (eucalyptol). The results showed that the essential oils extracted by means of SFME in 30 min were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained using conventional HD over 120 min. In addition, SFME generates less waste and less solvent, consumes less energy, and provides a higher yield for a shorter extraction time, which is advantageous for the extraction of the T. mastichina essential oil compared to SD. The antioxidant and antimicrobial activities of the T. mastichina essential oil obtained from either SFME or conventional extraction methods (SD or HD) showed a similar pattern. Large-scale experiments using this SFME procedure showed a potential industrial application.The authors acknowledge the Fundação para a Ciência e Tecnologia (FCT), Fundo Europeu de Desenvolvimento Regional (FEDER), and COMPETE 2020 for their financial support under theresearch project “The development of dermo-biotechnological applications using natural resourcesin the Beira and Serra da Estrela regions—DermoBio”, ref. SAICT-POL/23925/2016, presentedin the Notice for the Presentation of Applications No. 02/SAICT/2016—Scientific Research andTechnological Development Projects (IC & DT) in Co-Promotion (PDF) Solvent-Free Microwave Extraction of Thymus mastichina Essential Oil: Influence on Their Chemical Composition and on the Antioxidant and Antimicrobial Activities.info:eu-repo/semantics/publishedVersio

Biofortified Diets Containing Algae and Selenised Yeast: Effects on Growth Performance, Nutrient Utilization, and Tissue Composition of Gilthead Seabream (Sparus aurata)

Efforts have been made to find natural, highly nutritious alternatives to replace fish meal (FM) and fish oil (FO), which can simultaneously promote fish health and improve the nutritional quality of filets for human consumption. This study evaluated the impact of biofortified diets containing microalgae (as replacement for FM and FO), macroalgae (as natural source of iodine) and selenised yeast (organic source of selenium) on gilthead seabream growth, nutrient utilization, tissue composition and gene expression. A control diet (CTRL) with 15% FM and 5.5% FO was compared with three experimental diets (AD1, AD2, and AD3), where a microalgae blend (Chlorella sp., Tetraselmis sp., and DHA-rich Schizochytrium sp.) replaced 33% of FM. Diet AD1 contained 20% less FO. Diets were supplemented with Laminaria digitata (0.4% AD1 and AD2; 0.8% AD3) and selenised yeast (0.02% AD1 and AD2; 0.04% AD3). After feeding the experimental diets for 12 weeks, growth was similar in fish fed AD1, AD2, and CTRL, indicating that microalgae meal can partially replace both FM and FO in diets for seabream. But AD3 suppressed fish growth, suggesting that L. digitata and selenised yeast supplementation should be kept under 0.8 and 0.04%, respectively. Despite lower lipid intake and decreased PUFAs bioavailability in fish fed AD3, compared to CTRL, hepatic elovl5 was upregulated resulting in a significant increase of muscle EPA + DHA. Indeed, filets of fish fed AD2 and AD3 provided the highest EPA + DHA contents (0.7 g 100 g–1), that are well above the minimum recommended values for human consumption. Fish consuming the AD diets had a higher retention and gain of selenium, while iodine gain remained similar among diets. Upregulation of selenoproteins (gpx1, selk, and dio2) was observed in liver of fish fed AD1, but diets had limited impact on fish antioxidant status. Overall, results indicate that the tested microalgae are good sources of protein and lipids, with their LC-PUFAs being effectively accumulated in seabream muscle. Selenised yeast is a good fortification vehicle to increase selenium levels in fish, but efforts should be placed to find new strategies to fortify fish in iodineThis work has received funding from the European Union’s Horizon 2020 Research and Innovation Programe under Grant Agreement No. 773400 (SEAFOODTOMORROW) and from the project ATLANTIDA (ref. NORTE-01-0145-FEDER-000040), supported by the Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement and through the European Regional Development Fund (ERDF). This work received financial support from REQUIMTE/LAQV national funds (FCT) through project UID/QUI/50006/2019. LV acknowledges national funds provided by FCT to CIIMAR (UIDB/04423/2020 and UIDP/04423/2020), PP-F acknowledges MAR2020 national funds provided to IPMA (DIVERISAQUA project - 16-02-01-FEAM-66) and MF acknowledges FCT for the grant SFRH/BD/144843/2019.info:eu-repo/semantics/publishedVersio

Association of lifestyle with deep learning predicted electrocardiographic age

BackgroundPeople age at different rates. Biological age is a risk factor for many chronic diseases independent of chronological age. A good lifestyle is known to improve overall health, but its association with biological age is unclear.MethodsThis study included participants from the UK Biobank who had undergone 12-lead resting electrocardiography (ECG). Biological age was estimated by a deep learning model (defined as ECG-age), and the difference between ECG-age and chronological age was defined as Δage. Participants were further categorized into an ideal (score 4), intermediate (scores 2 and 3) or unfavorable lifestyle (score 0 or 1). Four lifestyle factors were investigated, including diet, alcohol consumption, physical activity, and smoking. Linear regression models were used to examine the association between lifestyle factors and Δage, and the models were adjusted for sex and chronological age.ResultsThis study included 44,094 individuals (mean age 64 ± 8, 51.4% females). A significant correlation was observed between predicted biological age and chronological age (correlation coefficient = 0.54, P &lt; 0.001) and the mean Δage (absolute error of biological age and chronological age) was 9.8 ± 7.4 years. Δage was significantly associated with all of the four lifestyle factors, with the effect size ranging from 0.41 ± 0.11 for the healthy diet to 2.37 ± 0.30 for non-smoking. Compared with an ideal lifestyle, an unfavorable lifestyle was associated with an average of 2.50 ± 0.29 years of older predicted ECG-age.ConclusionIn this large contemporary population, a strong association was observed between all four studied healthy lifestyle factors and deaccelerated aging. Our study underscores the importance of a healthy lifestyle to reduce the burden of aging-related diseases

Engineering single-atom Fe-N active sites on hollow carbon spheres for oxygen reduction reaction

Seeking alternatives to noble metals-based electrocatalysts for oxygen reduction reaction (ORR), hollow carbon spheres (CSs) were finely tuned with stable single-atom Fe-N species through a synthesis methodology requiring only earth-abundant metal precursors. CSs with different sizes were synthesized by sol-gel polycondensation of resorcinol with formaldehyde over silica nanoparticles, followed by thermal annealing and silica etching. A catalyst screening revealed the positive impact of both the hollow core and structural defects of the CSs for ORR. Single-atom Fe-N active sites were introduced on the best performing CSs through simultaneous incorporation of iron and nitrogen precursors, and glucose. A significant enhancement in ORR activity was observed despite the small iron load introduced (0.12 wt%). ORR performance indicators, advanced characterization, and molecular simulation studies revealed nitrogen's crucial role in anchoring individual iron atoms and modulating the charge density nearby the active sites (increase of 80 mV in the half-wave potential). Adding glucose as a chelating agent enhances the metal-heteroatom coordination and subsequent dispersion of iron, accounting for an increase of 20 mV in the half-wave potential, an average of electrons transferred as high as 3.9 (at 0.4 V vs. RHE), and higher stability (99%) than that of a platinum-based (20 wt%) electrocatalyst (92%).11 página

Food and fuel microalgae applications: insights from portuguese experience [Resumo]

Microalgae have a wide range of application fields, from food to fuels, to pharmaceuticals & fine chemicals, aquaculture and environmental bioremediation, among others. Spirulina and Chlorella have been used as food sources since ancient times, due to their high and balanced nutritional value. Our research group in Lisbon has developed a range of food products (emulsions, gelled desserts, biscuits and pastas) enriched with freshwater and marine microalgae (Spirulina, Chlorella, Haematococcus, Isochrysis and Diacronema). The developed products presented attractive and stable colours, high resistance to oxidation and enhanced rheological properties. Some of these products will be prepared at the Post-Congress Course “Functional Foods Development” at the University of Antofagasta. More recently, a great interest has arisen on using microalgae for biofuel production. The same group has also been exploring several marine and freshwater species for biofuel production (e.g., biodiesel, bioethanol, biohydrogen and biomethane) within a biorefinery approach, in order to obtain high and low-value co-products using integral biomass maximizing the energy revenue. Namely, supercritical fluid extraction of Nannochloropsis sp. allowed the recovery of valuable carotenoids and lipids, prior to bioH2 production through dark fermentation of the residual biomass. Also, Scenedesmus obliquus residues after sugars (for bioethanol) and lipids (for biodiesel) extraction has been anaerobically digested attaining high biomethane yields. Regarding sustainability issues, the current trend of our group is now focused on using liquid effluents and high CO2 levels for low cost microalgae growth, contributing to a lower water demand, primary energy consumption and global warming potential by reducing the need for potable water and fertilizers (P, N) and increasing CO2 mitigation. Microalgae biomass has been successfully used for urban wastewater treatment with subsequent bioH2 production, in a biorefinery approach. Presently, ammonium-rich raw effluents from piggeries and poultry industry are being effectively used for microalgae growth avoiding any pre-treatment step

Hemocyanin facilitates lignocellulose digestion by wood-boring marine crustaceans

Woody (lignocellulosic) plant biomass is an abundant renewable feedstock, rich in polysaccharides that are bound into an insoluble fiber composite with lignin. Marine crustacean woodborers of the genus Limnoria are among the few animals that can survive on a diet of this recalcitrant material without relying on gut resident microbiota. Analysis of fecal pellets revealed that Limnoria targets hexose-containing polysaccharides (mainly cellulose, and also glucomannans), corresponding with the abundance of cellulases in their digestive system, but xylans and lignin are largely unconsumed. We show that the limnoriid respiratory protein, hemocyanin, is abundant in the hindgut where wood is digested, that incubation of wood with hemocyanin markedly enhances its digestibility by cellulases, and that it modifies lignin. We propose that this activity of hemocyanins is instrumental to the ability of Limnoria to feed on wood in the absence of gut symbionts. These findings may hold potential for innovations in lignocellulose biorefining