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Sulfomethylation of radiata pine kraft lignin was performed using formaldehyde and sodium sulfite under alkaline conditions to determine its potential as a mineral depressant for the separation of molybdenite and chalcopyrite by froth flotation. Optimal conditions for the sulfomethylation reaction were 20% (w/w) Na2SO3 at 130 °C for 4.2 h, which resulted in lignin with a sulfonate content of 2.2 mmol/g. Microflotation assays showed that the optimized sulfomethylated kraft lignin (OSKL) depressed the molybdenite in flotation by 93% using 200 mg/L OSKL, while only 5% chalcopyrite depression was achieved. The performance of OSKL was compared with those of commercial lignosulfonates, and the OSKL displayed a better ability to separate molybdenite and chalcopyrite, even at lower concentration doses. FTIR and 1H-NMR analyses showed that sulfonic groups were incorporated into the C5 position of the aromatic ring and into the aliphatic chain of the OSKL. The hydroxymethyl content of the OSKL was increased, and most β-O-4′, β-1′ and β-5′ bonds were broken, with the exception of the β-β’ bond. Sulfomethylation gives kraft lignin the chemical characteristics of a wood-based molybdenite depressant, making it an alternative to current reagents used in the chalcopyrite-molybdenite flotation process.

Metal-regulatory transcription factor 1 (MTF1) is a conserved metal-binding transcription factor in eukaryotes that binds to conserved DNA sequence motifs, termed metal response elements. MTF1 responds to both metal excess and deprivation, protects cells from oxidative and hypoxic stresses, and is required for embryonic development in vertebrates. To examine the role for MTF1 in cell differentiation, we use multiple experimental strategies [including gene knockdown (KD) mediated by small hairpin RNA and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9), immunofluorescence, chromatin immunopreciptation sequencing, subcellular fractionation, and atomic absorbance spectroscopy] and report a previously unappreciated role for MTF1 and copper (Cu) in cell differentiation. Upon initiation of myogenesis from primary myoblasts, both MTF1 expression and nuclear localization increased. Mtf1 KD impaired differentiation, whereas addition of nontoxic concentrations of Cu(+)-enhanced MTF1 expression and promoted myogenesis. Furthermore, we observed that Cu(+) binds stoichiometrically to a C terminus tetra-cysteine of MTF1. MTF1 bound to chromatin at the promoter regions of myogenic genes, and Cu addition stimulated this binding. Of note, MTF1 formed a complex with myogenic differentiation (MYOD)1, the master transcriptional regulator of the myogenic lineage, at myogenic promoters. These findings uncover unexpected mechanisms by which Cu and MTF1 regulate gene expression during myoblast differentiation.—Tavera-Montañez, C., Hainer, S. J., Cangussu, D., Gordon, S. J. V., Xiao, Y., Reyes-Gutierrez, P., Imbalzano, A. N., Navea, J. G., Fazzio, T. G., Padilla-Benavides, T. The classic metal-sensing transcription factor MTF1 promotes myogenesis in response to copper.

Dp40 is ubiquitously expressed, including in the central nervous system. Dp40 mRNA and protein are detected in the early stages and postnatal stages of the mouse brain, respectively. In addition to being present in the nucleus, membrane, and cytoplasm, Dp40 is detected in neurites and postsynaptic spines in hippocampal neurons. Although Dp40 is expressed from the same promoter as Dp71, its role in the cognitive impairment present in Duchenne muscular dystrophy patients is still unknown. Here, we studied the effects of overexpression of Dp40 and Dp40L170P (a mutant of Dp40) during the neuronal differentiation process of PC12 Tet-On cells. We found that Dp40 overexpression increased the percentage of PC12 cells with neurites and neurite length, while Dp40L170P overexpression decreased them compared to Dp40 overexpression. Two-dimensional gel electrophoresis analysis carried out in nerve growth factor-differentiated PC12-Dp40L170P cells showed that the protein expression profile was modified compared to that of the control cells (PC12 Tet-On). The proteins with the highest upregulated expression were α-internexin and S100a6, which are involved in cytoskeletal structure. The expression of vesicle-associated membrane proteins increased in differentiated PC12-Dp40 cells, in contrast to PC12-Dp40L170P cells, while neurofilament light-chain was decreased in both differentiated cells. HspB1 was absent in undifferentiated cells and weakly detected in all differentiated cells. These results suggest that the subcellular distribution and expression of Dp40 has an important role in the neurite outgrowth of PC12 cells through the regulation of proteins involved in neurofilaments and exocytosis of synaptic vesicles, functions that might be affected in PC12-Dp40L170P.

The objective of this study was to investigate structural changes and lignin redistribution in Eucalyptus globulus pre-treated by steam explosion under different degrees of severity (S0), in order to evaluate their effect on cellulose accessibility by enzymatic hydrolysis. Approximately 87.7% to 98.5% of original glucans were retained in the pre-treated material. Glucose yields after the enzymatic hydrolysis of pre-treated material improved from 19.4% to 85.1% when S0 was increased from 8.53 to 10.42. One of the main reasons for the increase in glucose yield was the redistribution of lignin as micro-particles were deposited on the surface and interior of the fibre cell wall. This information was confirmed by laser scanning confocal fluorescence and FT-IR imaging, these microscopic techniques show changes in the physical and chemical characteristics of pre-treated fibres. In addition, the results allowed the construction of an explanatory model for microscale understanding of the enzymatic accessibility mechanism in the pre-treated lignocellulose.

Lignin is one of the wood and plant cell wall components that is available in large quantities in nature. Its polyphenolic chemical structure has been of interest for valorization and industrial application studies. Lignin can be obtained from wood by various delignification chemical processes, which give it a structure and specific properties that will depend on the plant species. Due to the versatility and chemical diversity of lignin, the chemical industry has focused on its use as a viable alternative of renewable raw material for the synthesis of new and sustainable biomaterials. However, its structure is complex and difficult to characterize, presenting some obstacles to be integrated into mixtures for the development of polymers, fibers, and other materials. The objective of this review is to present a background of the structure, biosynthesis, and the main mechanisms of lignin recovery from chemical processes (sulfite and kraft) and sulfur-free processes (organosolv) and describe the different forms of integration of this biopolymer in the synthesis of sustainable materials. Among these applications are phenolic adhesive resins, formaldehyde-free resins, epoxy resins, polyurethane foams, carbon fibers, hydrogels, and 3D printed composites.

Polyacrylics have been considered for a broad range of material applications, including coatings, dental applications, and adhesives. In this experimental study, the casting potential of a group of (co)monomers belonging to the acrylic family has been explored to enable a more sustainable use of these polymer materials in the medical and veterinary science field. The individual contributions of each comonomer have been analyzed, the reaction conversion has been studied via gas chromatography (GC), the rheological behavior has been characterized via stress-controlled measurements, and the final mechanical properties have been obtained from tensile, flexure, and impact tests. The GC results allow assessing the pot life and thus the working window of the casting process. For the rheological measurements, which start from low-viscous mixtures, a novel protocol has been introduced to obtain accurate absolute data. The rheological data reflect the time dependencies of the GC data but facilitate a more direct link with the macroscopic material data. Specifically, the steep increase in the viscosity with increasing reaction time for the methyl methacrylate (MMA)/ethylene glycol dimethyl methacrylate (EGDMA) case (2% crosslinker) allows maximizing several mechanical properties: the tensile/flexure modulus, the tensile/flexure stress at break, and the impact strength. This opens the pathway to more dedicated chemistry design for corrosion casting and polyacrylic material design in general.

Eucalyptus globulus is the second most important economic forest species in Chile. Its main use is in the kraft pulp industry, where large amounts of bark waste are generated. Due to its fibrous characteristics, E. globulus bark is proposed as an alternative source of fibres for papermaking. This study focuses on obtaining fibres for liner paper manufacture. A neutral sulphite semi-chemical (NSSC) process was performed, varying the sodium sulphite (5% to 16%) and the sodium carbonate (2% and 4%) concentrations using two reaction temperatures (160°C and 170°C). The NSSC process at 170°C, 16% of sulphite, and 2% of sodium carbonate proved to be the best condition to obtain higher mechanical performance of papers. As the pulping conditions become more drastic, the yield drops, and the physicomechanical properties of paper increases. Results showed that pulps from E. globulus bark could turn into source of fibres for papermaking and other related products.

Low-density polyethylene composites containing different sizes of calcium oxide (CaO) nanoparticles were obtained by melt mixing. The CaO nanoparticles were synthesized by either the sol-gel or sonication methods, obtaining two different sizes: ca. 55 nm and 25 nm. These nanoparticles were used either as-synthesized or were modified organically on the surface with oleic acid (Mod-CaO), at concentrations of 3, 5, and 10 wt% in the polymer. The Mod-CaO nanoparticles of 25 nm can act as nucleating agents, increasing the polymer&rsquo, s crystallinity. The Young&rsquo, s Modulus increased with the Mod-CaO nanoparticles, rendering higher reinforcement effects with an increase as high as 36%. The reduction in Escherichia coli bacteria in the nanocomposites increased with the amount of CaO nanoparticles, the size reduction, and the surface modification. The highest antimicrobial behavior was found in the composites with a Mod-CaO of 25 nm, presenting a reduction of 99.99%. This strong antimicrobial effect can be associated with the release of the Ca2+ from the composites, as studied for the composite with 10 wt% nanoparticles. The ion release was dependent on the size of the nanoparticles and their surface modification. These findings show that CaO nanoparticles are an excellent alternative as an antimicrobial filler in polymer nanocomposites to be applied for food packaging or medical devices.

In the treatment of cancer, over the last decade different drugs delivery systems have been developed to increase therapeutic specificity to improve drug's efficacy, and safety by increasing bioavailability. Among these systems, small nucleic acid molecules with a three-dimensional structure, known as aptamers, have shown several advantages. Several approaches to design aptamers require modifications from starting libraries of DNA sequences. Here, we describe cell-internalization SELEX (Systematic Evolution of Ligands by Exponential Enrichment), a sophisticated technique based on RNA aptamers as a starting point, that enables design functional aptamers as drug-delivery tools. This variation of the original SELEX technique using RNA aptamers instead DNA aptamers allows to obtain aptamers that are internalized in prostate cancer cells using as a starting point an RNA aptamer library with 76 nucleotides. The major advantage of this technique is that modifications are not required in the initial library, as initial T7 transcription promoter or 2'F nucleotides before sequencing.

Brg1 (Brahma related gene 1) is one of two mutually exclusive ATPases that can act as the catalytic subunit of mammalian SWI/SNF chromatin remodeling enzymes that facilitate utilization of the DNA in eukaryotic cells. Brg1 is a phospho-protein and its activity is regulated by specific kinases and phosphatases. Previously, we showed that Brg1 interacts with and is phosphorylated by casein kinase 2 (CK2) in a manner that regulates myoblast proliferation. Here we demonstrate that the Brg1-CK2 interaction occurred during mitosis in embryonic somites and in primary myoblasts derived from satellite cells isolated from muscle tissue. The interaction of CK2 activity with Brg1 and the incorporation of a number of other subunits into the mSWI/SNF enzyme complex were independent of CK2 enzymatic activity. CK2-mediated hyperphosphorylation of Brg1 was observed in mitotic cells derived from multiple cell types and organisms, suggesting functional conservation across tissues and species. The mitotically hyperphosphorylated form of Brg1 was localized with soluble chromatin, demonstrating that CK2-mediated phosphorylation of Brg1 is associated with specific partitioning of Brg1 within sub-cellular compartments. Thus CK2 acts a mitotic kinase that regulates Brg1 phosphorylation and sub-cellular localization.HIGHLIGHTSInteractions between CK2 and the Brg1 chromatin remodeling enzyme occur during mitosisCK2-Brg1 interactions are independent of CK2 catalytic activityCK2-mediated phosphorylation of Brg1 is a mitotic eventCK2-mediated phosphorylation of Brg1 is conserved across mammalian cell typesThe mitotically hyperphosphorylated form of Brg1 is localized with soluble chromatin

Amphiphysin 2 and members of the BAR-domain family of proteins participate in a wide array of cellular processes including cell cycle and endocytosis. Given that amphiphysin 2 is related to diverse cell responses as a result of metabolic stress, we investigated in macrophages whether oxidative stress originated by the internalization of oxidized low density lipoproteins (oxLDL) affect both, the expression of amphiphysin 2 and its binding partner c-Myc. Here we report that under oxidative stress, a complex formation between amphiphysin 2(Bin1) and c-Myc allows the cell to develop a novel survival equilibrium state established between cell proliferation and cell death. We propose that under conditions of oxidative stress given by the internalization of oxLDL, macrophages employ the formation of the amphiphysin 2(Bin1)/c-Myc complex as a control mechanism to initially avoid the process of cell death in an attempt to prolong cell survival.

In this contribution we want to show how the intramineral proteins affect the crystal morphology of calcite crystals grown in vitro. Intramineral proteins from emu eggshells and two crocodile species were isolated, purified by ultrafast liquid chromatography, and characterized by biochemical and biophysical methods. We saw that the crystal habit of calcite was modified when intramineral proteins were present at certain concentration. Therefore, all crystal species were individually characterized by scanning electron microscopy (SEM) and by electron diffraction with an electron-reduced dosage in transmission electron microscopy. Additionally, transversal SEM micrographs of eggshells of four types of species, namely, emu, crocodile, hen, and dinosaur (70 million years old), were compared to track the changes produced by the interacting intramineral proteins. Finally, the organic sulfur content analysis of these eggshells was performed by using X-ray absorption techniques like X-ray fluorescence and X-ray ab...

Osteoporosis is a skeletal disease mainly affecting women over 50 years old and it represents a serious public health problem because of the high socioeconomic burden. This disease is characterized by deterioration of bone microarchitecture, low bone mineral density (BMD), and increased risk of fragility fractures. This study aimed to identify serum useful proteins as biomarkers for the diagnosis and/or prognosis of osteoporosis and fracture risk. We collected 446 serum samples from postmenopausal women aged &ge, 45 years old. Based on the BMD measurement, we classified the participants into three groups: osteoporotic, osteopenic, and normal. In an initial discovery stage, we conducted a proteomic approach using two-dimensional differential gel electrophoresis (2D-DIGE). The peptides into the spots of interest were identified through matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF/TOF). Enzyme-linked immunosorbent assay (ELISA) was performed to validate the proteins of interest. We identified 27 spots of interest when comparing low BMD versus normal BMD postmenopausal women. Based on their relevance in bone metabolism, we analyzed three proteins: ceruloplasmin (CP), gelsolin (GSN), and vitamin D-binding protein (VDBP). Our results demonstrated that low serum VDBP levels correlate with low BMD (osteopenic and osteoporotic). Therefore, VDBP could be considered as a novel, potential, and non-invasive biomarker for the early detection of osteoporosis.

[EN] Effective antimicrobial polymeric nanocomposites were prepared with low density polyethylene (LDPE) and zinc oxide nanoparticles by melt compounding. These nanoparticles (~17 nm) obtained by the sol¿gel method, were used both as-synthesized and modified organically with oleic acid (Mod-ZnO). Young¿s modulus increased ~15 and 18% for LDPE/ZnO and LDPE/Mod-ZnO, respectively, compared to neat LDPE. When these composites were irradiated with white light, they showed an increase with nanoparticle incorporation, and the antimicrobial properties against E. coli were ~96¿99%. The release of the Zn cations was related to the antimicrobial properties. These nanocomposites are attractive for use as food packaging without external irradiation., Financial support provided by the Innovation Found for Competitiveness of the Chilean Economic Development Agency (CORFO) under Grant 13CEI2-21839 is gratefully acknowledged.

JMJD6 is a member of the Jumonji C domain containing enzymes that demethylate and/or hydroxylate substrate proteins. It is a multi-functional protein that has been implicated in disparate aspects of transcriptional and post-transcriptional control of gene expression, including but not limited to enhancer and promoter binding, release of paused RNA polymerase II, control of splicing, and interaction with the translation machinery. JMJD6 contributes to multiple aspects of animal development, including adipogenesis modeled in culture. We mutated proposed or characterized domains in the JMJD6 protein to better understand the requirement for JMJD6 in adipogenic differentiation. Mutation of JMJD6 amino acids that mediate binding of iron and 2-oxogluterate, which are required cofactors for enzymatic activity, had no impact on JMJD6 function, showing that catalytic activity is not required for JMJD6 contributions to adipogenic differentiation. In addition, we documented the formation of JMJD6 oligomers and showed that catalytic activity is not required for oligomerization, as has been reported previously. We also observed no effect of mutations in the sumoylation site and in the poly-serine stretch. In contrast, mutation of the AT hook-like structure, which mediates interaction with DNA and/or RNA, compromised JMJD6 function by blocking its ability to interact with chromatin at genes that express regulators of adipogenesis. The ability of JMJD6 to interact with nucleic acids may be a critical requirement for its function in adipogenic differentiation. The requirement for the AT hook-like domain and the lack of requirement for catalytic activity giving rise to the idea that co-activation of transcription by JMJD6 may be functioning as a scaffold protein that supports the interactions of other critical regulators.

MTF1 is a conserved metal-binding transcription factor in eukaryotes that binds to conserved DNA sequence motifs, termed metal response elements (MREs). MTF1 responds to metal excess and deprivation, protects cells from oxidative and hypoxic stresses, and is required for embryonic development in vertebrates. We used multiple strategies to identify an unappreciated role for MTF1 and copper (Cu) in cell differentiation. Upon initiation of myogenesis from primary myoblasts, MTF1 expression increased, as did nuclear localization.Mtf1knockdown impaired differentiation, while addition of non-toxic concentrations of Cu+enhanced MTF1 expression and promoted myogenesis. Cu+bound stoichiometrically to a C-terminus tetra-cysteine of MTF1. MTF1 bound to chromatin at the promoter regions of myogenic genes and binding was stimulated by copper. MTF1 formed a complex with MyoD at myogenic promoters, the master transcriptional regulator of the myogenic lineage. These studies establish novel mechanisms by which copper and MTF1 regulate gene expression in myoblast differentiation.

IntroductionUric acid has gained considerable attention as a potential neuroprotective agent in stroke during the last decades, however, its role in the pathophysiology of ischemic stroke remains poorly understood. A serial evaluation of uric acid levels during the acute phase of stroke and its association with infarct size on magnetic resonance imaging is lacking.MethodsWe present a cohort study of 31 patients with ischemic stroke who were not candidates for thrombolysis according to current criteria at the time. We performed daily measurements of serum uric acid and total antioxidant capacity of plasma during the first week after symptoms onset and 30 days after. Infarct size was determined in the acute phase by a DWI sequence and the final infarct size with a control MRI (FLAIR) at day 30.ResultsUric acid significantly decreases between days 2 to 6 compared to day 1, after adjustment by sex, age and DWI at diagnosis, with a nadir value at 72h. A mixed model analysis showed a negative association between DWI at diagnosis and uric acid evolution during the first week after stroke. Moreover, multivariable linear regression of uric acid values during follow up on DWI volumes demonstrated that DWI volume at diagnosis is negatively associated with uric acid levels at day 3 and 4. There were no significant associations between total antioxidant capacity of plasma and DWI at diagnosis, or FLAIR at any point.DiscussionPatients with larger infarcts exhibited a significant decrease in serum uric acid levels, accounting for a more prominent reactive oxygen species scavenging activity with subsequent consumption and decay of this antioxidant. The different kinetics of total antioxidant capacity of plasma and serum uric acid levels suggests a specific role of uric acid in the antioxidant response in ischemic stroke.

The objective of this research was to study the chemical and nanomechanical characteristics of native woods grown in southern Chile region. The species analysed were Drimys winteri, Laureliopsis philippiana, Aextoxicon puctatum, Nothofagus alpina, Nothofagus dombeyi, Laurelia sempervirens, Austrocedrus chilensis and Fitzroya cupressoides. The samples were collected from the regions of Biobío (37° S, 73° W), Araucanía (37° S, 71° W) and Los Lagos (40° S, 73° W). Chemical analysis reported that glucan content of native woods was between 39% and 44% and lignin content between 28% and 35%. The nanomechanical properties analysed in the secondary cell wall (S2 layer) and middle lamella (ML) were elastic modulus (E), hardness (H) and ductility ratio (E/H). Values for ES2 were between 12.0 and 15.4 GPa and for EML between 4.3 and 6.6 GPa. Hardness values were similar in ML and S2 (≈0.3 GPa). The compilation of results showed high correlations between ES2 and carbohydrate content (r = 0.80), between ES2 and hemicellulose content (r = 0.89), and between HS2 and lignin content (r = 0.88).Keywords: cell wall properties, chemical characterisation, nanoindentation, native woods

Biofilms are structures that confer adaptive ability to and facilitate the virulence of fungal pathogens. Certain multi-functional proteins have been shown to be involved in fungal pathogenesis and these proteins may also be implicated in biofilm formation. The aim of this study was to identify a fungal agent isolated from the human cornea, to analyze the ability of this organism to form biofilms in vitro and to investigate protein expression in this condition. The fungus was identified by phylogenetic inference analysis. Biofilm formation and structure were evaluated by colorimetric methods and by optical and electron microscopy. We also resolved proteins obtained from biofilms and planktonic cultures by two-dimensional gel electrophoresis and identified those proteins by mass spectrometry. The fungus was identified as Fusarium falciforme. Colorimetric analysis and microscopy revealed that the highest level of biofilm formation was obtained at a concentration of 1 × 106 conidia/mL with 96 h of incubation at 28 °C. The biofilm architecture consisted of an extracellular matrix that embedded fungal filaments. We found nineteen proteins that were over-expressed in biofilms, as compared with planktonic cultures, and six proteins with unique expression in biofilms. Among the more abundant proteins identified were: transketolase, a putative antigen 1, enolase, phosphoglycerate kinase and ATP-citrate synthase. Some of these proteins are involved in basal metabolism, function as multi-functional proteins or have been described as potential virulence factors. We focused on the expression in biofilm of the enzyme, enolase, which was determined by real-time PCR. Our findings provide a perspective on the proteins associated with the formation of biofilms in vitro by an F. falciforme keratitis isolate.

The combination of hemicellulose pre-hydrolysis by dilute acid or steam-explosion followed by kraft pulping was one approach evaluated in this work to generate pulps from radiata pine wood chips amenable to saccharification by enzymatic hydrolysis. Dilute acid (combined severity factor, CS = 1.67) and steam explosion (severity factor, log Ro = 4.09) treatments were able to solubilize approximately 53% and 63% of the original hemicelluloses content in wood, respectively. Extracted wood chips were subjected to kraft cooking (170 °C, 16-18% active alkali, 30% sulfidity and 1200 H-factor) to produce pulps that were further saccharified by cellulases. Lignin removal increased with increasing active alkali, affording delignification levels 28% for dilute acid and 68% for steam explosion extraction pretreatment pulps. Enzymatic digestibility of P. radiata pulps were low, and only samples pretreated by steam explosion reached glucan-to-glucose conversion near to 75%; this treatment was 31% and 37% higher than that obtained with wood chips that were pretreated by dilute acid extraction.

The low temperature water–gas shift (WGS) reaction has been studied over Ni–CeO2/Graphene and Ni/Graphene. The catalysts were prepared with 5 wt.% Ni and 20 wt.% CeO2 loadings, by deposition-precipitation employing sodium hydroxide and urea as precipitating agents. The materials were characterized by TEM, powder X-ray diffraction, Raman spectroscopy, H2-temperature-programmed reduction and X-ray photoelectron spectroscopy (XPS). The characterization and the reaction results indicated that the interaction between the active species and the support is higher than with activated carbon, and this hinders the reducibility of ceria and thus the catalytic performance. On the other hand, the presence of residual sodium in samples prepared by precipitation with NaOH facilitated the reduction of ceria. The catalytic activity was highly improved in the presence of sodium, what can be explained on the basis of an associative reaction mechanism which is favored over Ni-O-Na entities. Authors thank to CONICYT (Chile, Postdoc FONDECYT 3130483) and Ministerio de Economía y Competitividad (Spain, MAT2010-21147 and MAT2013-45008-P) for financial support.

Pinus radiata D. Don wood chips were submitted to a hydrothermal (HT) process, which is a pretreatment with pressurized water at P-factors of 20 (E1) and 1200 (E2), leading to 27% and 56% of hemicellulose removal, respectively. The residual wood chips were pulped by the chemithermomechanical (CTMP) and kraft processes. The pulp yield in the HT/CTMP process was in the range of 56–75%. The cellulose yields were not affected by the HT pretreatment, whereas the solubilization of hemicelluloses and lignin was intensified. The HT process provided energy savings in the refining of CTMP pulps, and the E1/CTMP pulp had a similar tensile and increased tear strength as the control wood. For kraft pulping, the HT wood chips demanded more active alkali (AA) to achieve a κ number (KN) of 30, and consequently, a decrease in pulp yield was observed (47.2% yield in the control and 44.4% and 37.8% in the E1 and E2 pulps, respectively). The fiber length decreased in the E1 and E2 kraft pulps compared with their control samples. In the E1 pulps, the tensile, tear, and burst indexes decreased by 10%, 25%, and 30%, respectively. Considering the low hemicellulose content and pulp viscosity in the range of 800–900 ml g-1, the mild HT process of P. radiata would be better suited for preparing cellulose-rich materials instead of paper-grade pulps under the biorefinery concept.

Conversion of protein -SH groups to disulfides is an early event during protein oxidation, which has prompted great interest in the study of thiol proteins. Chemical carcinogenesis is strongly associated with the formation of reactive oxygen species (ROS). The goal of this study was to detect thiol proteins that are sensitive to ROS generated during diethylnitrosamine (DEN) metabolism in the rat liver. DEN has been widely used to induce experimental hepatocellular carcinoma. We used modified redox-differential gel electrophoresis (redox-DIGE method) and mass spectrometry MALDI-TOF/TOF to identify differential oxidation protein profiles associated with carcinogen exposure. Our analysis revealed a time-dependent increase in the number of oxidized thiol proteins after carcinogen treatment; some of these proteins have antioxidant activity, including thioredoxin, peroxirredoxin 2, peroxiredoxin 6 and glutathione S-transferase alpha-3. According to functional classifications, the identified proteins in our study included chaperones, oxidoreductases, activity isomerases, hydrolases and other protein-binding partners. This study demonstrates that oxidative stress generated by DEN tends to increase gradually through DEN metabolism, causes time-dependent necrosis in the liver and has an oxidative effect on thiol proteins, thereby increasing the number of oxidized thiol proteins. Furthermore, these events occurred during the hepatocarcinogenesis initiation period.

Hemicelluloses from Pinus radiata wood chips were extracted using different conditions of temperature, time and initial pH of water (120 to 170°C, 30 to 120 min and pH 2 to 12, respectively). Results showed that hemicelluloses represented 26% of wood dry weight and, from this amount, hexoses are responsible for 64% of its composition. The analysis of extraction results showed that pH has a low effect in disassembling hemicelluloses from wood, and that time and temperature of reaction were the most important parameters. Maximal amount of hemicellulose extracted in the most severe conditions tested was between 12-16% (on wood basis). In these conditions approximately 40-50% of the hemicellulose in wood was solubilized. As observed by SEC analysis, the recovered hemicellulosic fractions were in the form of low molar mass oligomers with Mw varying from 3720 to 54300 g/mol. The FT-IR spectra show peak multiplicity between 1120 and 1000 cm-1 that is a typical characteristic of carbohydrates and only alkaline-extracted hemicelluloses showed the presence of lignin with a characteristic peak at 1509 cm-1.

As galactoglucomananas são as principais frações de hemiceluloses presentes nas madeiras moles e contêm, principalmente, as hexoses galactose, glicose e manose. O isolamento eficiente e seletivo dessas hemiceluloses é um obstáculo crítico a superar para sua utilização. Os objetivos deste trabalho foram extrair e caracterizar soluções aquosas ácidas e neutras de hemiceluloses de cavacos de madeira de Pinus radiata, bem como avaliar sua viabilidade para a produção de bioetanol. As hemiceluloses em P. radiata representam 26 g/100 g de madeira (base seca), e as hexoses são responsáveis por aproximadamente 64% dessa quantidade. De acordo com as diferentes condições de extração, cerca de 50% da fração hemicelulósica foi solubilizada e recuperada depois de uma precipitação com etanol. As frações recuperadas de hemiceluloses estavam na forma de oligômeros com peso molecular médio (Mw) variando entre 4x10³ e 4x10(5) g/mol. Os oligômeros hemicelulósicos foram hidrolisados com ácido sulfúrico diluído e os hidrolisados concentrados até aproximadamente 70 g/L hexosas e fermentados pela levedura Saccharomyces cerevisiae. Os resultados de fermentação indicaram que os açúcares obtidos dos extratos ácidos e neutros foram fermentados com rendimentos máximos de etanol de 63% e 54% (22 g/L e 19 g/L), respectivamente. A conversão de hemiceluloses da madeira em etanol é viável, porém seu baixo rendimento faz que o processo não seja economicamente atrativo, razão por que melhorias no processo ou usos alternativos das hemiceluloses devem ser avaliados. Galactoglucomannans are the major hemicellulosic fraction present in softwoods, and is mainly composed by the hexoses: galactose, glucose and mannose. The efficient and selective isolation of these hemicelluloses is regarded as one of the most critical obstacles to overcome for their utilization. The objective of the current work was to extract and characterize acidic and neutral aqueous solutions of hemicelluloses from Pinus radiata wood chips and investigate their feasibility for bioethanol production. Hemicelluloses in P. radiata represented 26 g/100 g wood (o.d.w.) and hexoses are responsible for approximately 64% of this amount. According to the different extraction conditions, approximately 50% of the hemicellulosic fraction was solubilized and recovered after precipitation with ethanol. The recovered hemicellulosic fractions were in the form of oligomers with weight-average molecular weigth (Mw) varying from 4x10³ to 4x10(5) g/mol. Hemicellulosic oligomers were hydrolyzed with dilute sulfuric acid and the hydrolysates concentrated until approximately 70 g/L of hexoses and fermented by Saccharomyces cerevisiae yeast. Fermentation results showed that sugar obtained from acid and neutral extractions were fermented to ethanol with maximum yields of 63% and 54% (22 g/ L and 19 g/L), respectively. The conversion of wood hemicellulosic substrates to ethanol is feasible but the low ethanol yields obtained make the process not economically attractive and optimization of the process or alternatives uses for hemicelluloses should be evaluated.

Inhibition of angiotensin-converting enzyme (ACE) and antithrombotic properties of peptides released from bovine caseins during fermentation by Lactobacillus casei Shirota and Streptococcus thermophilus were determined. Both species released ACE inhibitory peptides, whereas only Lb. casei Shirota produced antithrombotic activity. The highest thrombin inhibitory activity, 80.7%, was observed at 27 h of fermentation by Lb. casei Shirota. Active peptides were purified by HPLC; seven peptides were obtained, and their resistance to digestive enzymes, pepsin and trypsin, was evaluated. The most active peptide even after the hydrolysis was identified as YQEPVLGPVRGPFPIIV (fragment 193–209 of β-casein): it had an inhibition efficiency ratio for ACE of 0.14%/peptide concentration (μg mL−1), and a thrombin inhibition efficiency ratio of 4.6%/peptide concentration (μg mL−1). This peptide had been previously reported as an ACE-inhibitor, but this is the first time that it is evaluated for its thrombin inhibition activity.

This paper studies the effect of mesostructured materials in the stereo-selective hydrogenation of 3-hexyne at 298 K and 40 psig pressure of H 2 over Pd-supported catalysts at different substrate:palladium (S:Pd) molar ratios. The catalysts were prepared by impregnation using a toluene solution of Pd(acac) 2 to obtain a metal content close to 1 wt.% over SBA-15 with one-dimensional hexagonal structure, MCM-48 silica with cubic structure and three-dimensional pore system and MSU-γ alumina with a lathlike particle morphology. All the supports were characterised by nitrogen adsorption–desorption isotherms at 77 K, TEM, XRD and H 2 chemisorption and TEM measurements. The reactions were found to be zero order with respect to 3-hexyne concentration. The starting 3-hexyne produces primarily cis -3-hexene, which subsequently is either hydrogenated to hexane or isomerized to trans -3-hexene and 2-hexenes that are found in very small amounts depending on the nature of the support used. Palladium catalysts supported on SBA-15 was the most active and selective catalyst.

The effect of the sulfiding mixture (H 2 /H 2 S and N 2 /H 2 S) over Re/ZrO 2 and Re/ZrO 2 -sulfated catalysts in the hydrodeoxygenation (HDO) of 2-methoxyphenol (guayacol) in the presence of CS 2 has been studied. The catalysts were prepared by wet impregnation and characterized by X-ray diffraction (XRD), BET surface area, X-ray photoelectron spectroscopy (XPS) and surface acidity techniques. The reaction was carried out in a batch reactor at 300 °C and 5 MPa. Reaction rates for both catalysts increased upon sulfiding in N 2 /H 2 S mixture. This N 2 /H 2 S mixture promotes the formation of ReS (2 − x ) species over support surfaces and leads to an increase in the rate of direct demethoxylation and an enhancement in the phenol/cathecol ratio. An increase in the concentration of CS 2 leads to an increase in the HDO and cathecol and inhibits the demethoxylation of guayacol.

A series of Co/SiO 2 catalysts containing 10–30 wt.% Co were prepared by wet impregnation and tested in the Fischer Tropsch reaction using a simulated syngas (CO/H 2 ) mixture similar to that obtained in biomass gasification. The catalysts characterization included N 2 adsorption, temperature programmed reduction (TPR), X-ray photoelectron spectra (XPS) and transmission electron microscopy (TEM) techniques. The reaction was carried out in a stainless steel fixed bed reactor at 300 °C and 1 MPa. In general, activity increased almost linearly with increasing Co-loading, reaching maximum at about 20 wt.% Co and then levelled off. These results correlate with that derived from XPS. The Co/Si surface atomic ratios increased almost linearly up to about 20 wt.% Co due to gradual surface coverage by Co species. At higher loadings, cobalt form large crystal aggregates. The selectivity to C 8 –C 9 hydrocarbons increases whereas the C 14+ hydrocarbon follows an opposite trend upon increasing Co-loading. It was also observed that the selectivity to liquid fraction is a function of the Co crystallite size, that is longer hydrocarbons chains are formed on the smaller cobalt crystallites.

Fischer Tropsch reaction using a mixture similar to that obtained from biomass transformation (biosyngas) has been studied on promoted Co/SiO 2 catalysts. As promoters, Cu, Zn, Re and Ru at two different contents were analysed. The promoter affects both the reducibility and the dispersion of Co species, which have an important effect in the activity and selectivity of the studied catalysts. Re and Ru significantly increase both the activity and the selectivity to long chain hydrocarbons, whereas in those promoted by Cu and Zn the effect is strongly affected by the amount of promoter. In those with higher amount of promoter (0.5 wt%), the formation of surface spinels or the blocking of the Co active sites by the copper itself produces a drop in the catalytic activity. The product distribution of the liquid extract reveals the presence of hydrocarbons from C 6 to higher than C 14+ , in most of the catalysts.

Kinetics of the hydrogenation of citral and its intermediates over Ir/TiO2/SiO2 catalysts has been studied. The effect of various parameters such as the initial concentration, H2 pressure partial, temperature and weight of catalyst were examined. A high selectivity towards unsaturated alcohols using this catalyst was demonstrated. The initial rates increased linearly with the catalyst weight. The reaction rate obeys a kinetics represented by the Langmuir–Hinshelwood model. A single site model suggesting the surface reaction as the rate determining step provided the best fit of the experimental data for the hydrogenation of citral and alcohols (geraniol, nerol and citronellol), while a dual site represent the best kinetics for the hydrogenation of citronellal.

Catalytic hydrogenation of citral over iridium supported on TiO 2 , SiO 2 and mixed oxides TiO 2 /SiO 2 has been studied. The effect of the reduction temperatures (473 or 773 K) and the successive enrichment of TiO 2 were analyzed. The solids were characterized by H 2 chemisorption at room temperature, N 2 adsorption at 77 K, XRD, TEM, FTIR and XPS. The obtained results show that the high temperature reduction treatment (HT) produces an important enhancement in both the catalytic activity and selectivity towards the desired product. The behavior is explained on the basis of a surface enrichment in titania due to the migration of TiO x species on the Ir crystallites, which does not occur in those catalysts reduced at low temperature (LT) or in the catalyst supported on an inert oxide such as SiO 2 .

The catalytic behaviour of the series Fe2(TeO3)3 + × % MoO3 (X = 0–30 mol. %) in the oxidation of propylene in the gaseous phase has been studied. It has been found that the addition of Mo03 to the iron tellurite activates the reaction towards the partial oxidation to acrolein. From the characterisation of solids it is possible to conclude that the addition of MoO3 promotes the crystallinity of the iron tellurite. On the other hand, surface studies of the catalysts show that depending on the MoO3 loading, this component is present in various states which contribute in different ways to the catalytic action. Some explanations for the observed behaviour are proposed.

Extraction of hemicelluloses prior to pulping and conversion of the extracted hemicelluloses to other bioproducts could provide additional revenue to traditional pulp and paper industries. The effect of hemicelluloses pre-extraction with a hydrothermal (HT) process on Pinus radiata chemimechanical pulp (CMP) properties was investigated in this study. The HT extraction resulted in a release of 7% to 58% of the initial amount of hemicelluloses from the wood. The extraction yield increased with temperature and extraction time. This hemicellulosic fraction was in the form of low molar mass oligomers with molecular weights varying from 1.5 to 100 kDa. Compared with the control (unextracted) CMP pulp, the HT pre-extraction significantly reduced the refining energy to obtain a given fibrillation degree (freeness). The pulp yield with the HT/CMP process was in the range of 56% to 75%. Fiber properties of the pulps from pre-extracted wood, such as fiber length, were reduced, while increases in fiber width, fines content, fiber coarseness, and kink index were observed in comparison with the control pulps. The strength properties of CMP pulps decreased with increasing amounts of hemicellulose removal during the stage prior to pulping.

The acute kidney injury (AKI) observed during sepsis is due to an uncontrolled release of inflammatory mediators. Septic patients develop electrolytic disturbances and one of the most important is ionized hypocalcemia. AKI adversely affects the function of other organs and hypocalcemia is associated with cardiovascular and respiratory dysfunctions. Since carotid body chemoreceptors modulate the systemic inflammatory response during sepsis syndromes, we used pentobarbitone-anesthetized male Sprague–Dawley rats in control condition (SHAM surgery) and after bilateral carotid neurotomy (carotid chemo/baro-denervated, BCN). We evaluate serum creatinine (CRE), serum neutrophil gelatinase-associated lipocaline (NGAL), ionized calcium (iCa) and cardiac Troponin I (cTnI) 90 min after the IP administration of 15 mg/kg lipopolysaccharide (LPS) or saline. In the SHAM group, LPS failed to induce significant changes CRE, NGAL, or iCa, and increased cTnI. Conversely, in the BCN group LPS increased CRE and NGAL, decreased iCa, and enhanced the increase of cTnI. Our results suggest that carotid chemo/baro-receptors might contribute to the regulation of both renal function and calcemia during sepsis. In addition, results imply that the carotid chemo-baroreceptors serve as an immunosensory organ.

In the present work we have studied the effect of carbon supports with different graphitic character (carbon nanotubes, mesoporous graphite and activated carbon) on the catalytic performance of iridium nanoparticles on the liquid phase chemoselective hydrogenation of para-chloronitrobenzene at room temperature. The effect of the oxygen groups was also evaluated by oxidizing a portion of the carbon nanotubes. The Raman and XRD spectra showed that the mesoporous graphite displayed the strongest graphitic character. The characterization of the catalysts by HR-TEM, XPS and TPR-H2, showed that the catalysts had similar particle size and that the catalysts prepared over the previously oxidized support, Ir/CNTox, was not fully reduced. The activity and selectivity achieved with the catalyst Ir/CNT was the best among the samples and the presence of irdium oxide on Ir/CNTox diminished the yield to p-chloroaniline, being the worse catalyst. The reactivity of different isomers was also studied over Ir/CNT and it followed the order m > o > p. Authors thank to CONICYT (Chile, FONDECYT 3130483) and Generalitar Valenciana (Spain, PROMETEOII/2014/004–FEDER) for financial support.

We investigate possible interactions between acetylcholine (ACh)- and adenosine 5′-triphosphate (ATP)-induced responses of petrosal ganglion, where the perikarya of most sensory neurons of the glossopharyngeal nerve are located. Experiments were performed on petrosal ganglia excised from pentobarbitone-anesthetized cats, desheathed and perfused in vitro. Separate applications of ACh and ATP to the exposed surface of the ganglion induced bursts of antidromic potentials recorded from the carotid (sinus) nerve branch of the glossopharyngeal nerve, which frequencies were dependent on the dose of the applied agonists. The simultaneous application of previously determined ED50s of ACh and ATP provoked responses corresponding closely to the simple addition of the responses elicited by the separate application of each agent. Responses usually subsided within 1 min of stimuli application but were followed by periods of refractoriness to subsequent application of the same agent. After determining the timing for recovering from desensitization to the ED50s of ACh and ATP applied separately, ACh was applied while the preparation had been desensitized to ATP and then ATP was applied during desensitization to ACh, but responses obtained were similar to control responses induced by each agent separately. In summary, ACh- and ATP-induced responses of petrosal ganglion neurons are simply additive, followed by a few minute lasting desensitization, but cross-desensitization was not observed. Thus, ACh and ATP seem to operate through independent receptors, activating separate ionic channels, whose coincident currents do not interfere each other.

Higher plants form crystals of calcium oxalate in well-controlled conditions. This control is performed in specialized cells by an organic matrix composed by soluble and insoluble water macromolecules. The water-soluble protein matrix associated with the calcium oxalate crystals from bean seed coat (Phaseolus vulgaris) contains many polypeptides of different molecular masses. In this study, we observed that the water-soluble matrix macromolecules strongly inhibited the nucleation of calcium oxalate crystals (this inhibition was concentration dependent). Additionally, two proteins were isolated and purified from the water-soluble matrix with masses of 250 kDa called calcium oxalate macromolecule associated 1 (COMA1) and 27 kDa called calcium oxalate macromolecule associated 2 (COMA2). These proteins were also strong inhibitors of the nucleation of calcium oxalate monohydrate. On the other hand, we found that the modification in the morphology of calcium oxalate crystals due to the presence of water-soluble macromolecules (altogether) affected mainly the {1 2 0} face. Particularly, COMA1 and COMA2 separately had the same influence on the morphology of these crystals.

A series of palladium-ceria-supported catalysts prepared by the sol-gel method are characterized and their catalytic results are reported. It was found that the addition of ceria to alumina produces a highly dispersed catalyst when compared with their zirconia counterparts. However, the catalytic activity of the ceria zirconia series is higher, essentially due to the larger particle size of palladium. This result can be attributed to the structure-sensitive reaction of the combustion of methane.  2004 Society of Chemical Industry

Ovocleidin-17 (OC17) from Gallus gallus is one of the best candidates to control and regulate the deposition of calcium carbonate in the calcified eggshell layer. Here, the crystal structure of monomeric OC17, determined at a resolution of 1.5 A, was refined to a crystallographic R-factor of 20.1%. This is the first protein directly involved in a non-pathological biomineralization process resolved by x-ray diffraction to date. The protein has a mixed alpha/beta structure containing a single C-type lectin-like domain. However, although OC17 shares the conserved scaffold of the C-type lectins, it does not bind carbohydrates. Nevertheless, in vitro OC17 modifies the crystalline habit of calcium carbonate (CaCO3) and the pattern of crystal growth at intervals of 5-200 microg/ml. Determining the three-dimensional structure of OC17 contributes to a better understanding of the biological behavior of structurally related biomolecules and of the mechanisms involved in eggshell and other mineralization processes.

Trimetallic Pt–Re–Sn catalysts supported on chlorided alumina were prepared by successive impregnation, following different orders, of the metal precursors. The content of each metal was 0.3% (w/w). The catalysts were tested in the reaction of cyclohexane dehydrogenation which was also poisoned by sulphur. The results of bimetallic Pt–Sn and Pt–Re catalysts indicate that the influence of Sn in decreasing Pt activity is greater than that of Re. Trimetallic catalysts present smaller catalytic activity and thiotolerance than Pt and the bimetallics indicating an additive action of Re and Sn on Pt. The rate of deactivation during S addition is intermediate between the ones of Pt–Re and Pt–Sn, suggesting a simultaneous poisoning of Pt–Re and Pt–Sn sites. The metallic function was further characterised by means of TPR, H 2 chemisorption, TEM and CO-FT-IR spectroscopy. The results suggest an electronic transfer from Sn and Re to Pt, greatly influencing its catalytic properties.

Calcium oxalate crystals are a major biomineralization product in higher plants. Their biological function and use are not well understood. In this work, we focus on the isolation and crystallochemical characterization of calcium oxalate crystals from seed coats of Phaseolus vulgaris (prisms) and leaves of Vitis vinifera (raphides and druses) using ultrastructural methods. A proposal based on crystal growth theory was used for explaining the existence of different morphologies shown by these crystals grown inside specialized cells in plants.

Two different series of titania-supported iron catalysts prepared by the sol-gel method have been characterised and tested in the combustion of methane at atmospheric pressure. In each series, the effect of metal loading (1, 5 and 10 wt%) and gelation pH (3 and 9) were studied. Characterisation data of calcined catalysts, carried out by specific area measurement, TPR, X-ray diffraction, XPS and EPR revealed no significant changes in metal dispersion. The catalytic activity of the solids were evaluated in the combustion of methane under stoichiometric mixture of CH4/O2 from 473 K up to the temperature required for total combustion. The best performance was shown by catalysts having 5 wt.%, which is ascribed to a balance of factors like the presence of a sufficient concentration of iron at the surface, achievement of relatively high dispersion state for iron and the presence of Fe+3 ions incorporated to the lattice of titania.

The diffusion of some metals of the group A-II, of the periodic table of the elements inside a milky silica gel containing carbonate ions produces highly atypical precipitates characterized by their singular morphology. The precipitate is a self-assembled nanocomposite material with two clearly distinct phases: an amorphous (from silica gel) and a crystalline metal-carbonate phase. These materials usually called induced morphology crystalline aggregates (IMCA) represent a plausible model for experimental simulations and for the understanding of biomineralization processes in nature. In this contribution, we show how these aggregates are obtained. We also show how the typical morphology is modified due to the influence of 20 l -amino acids that are usually present in proteins. We have also introduced the first structural characterization using atomic force microscopy and image analysis in order to describe the IMCA from the theoretical and the experimental point of view. Finally, the results are compared with those images found in nature formed by means of biomineralization in living organisms (such as calcite crystals present in avian eggshells).

Background/AIMS: Osteoarthritis (OA), the commonest joint disorder, is a leading cause of disability. Symptomatic slow-acting drugs for OA (SYSADOA), particularly glucosamine plus chondroitin sulphate (GS/CS), are effective for symptom relief, protect joint cartilage and delay OA progression, with a good safety profile. D-002, a mixture of beeswax alcohols that inhibits both cyclooxygenase and 5-lipoxygenase activities, has been effective in experimental and clinical OA studies, showing also a chondroprotective effect.OBJECTIVES: To compare the effects of D-002 and GS/SC administered for 12 weeks on OA symptoms.METHODS: Participants were randomized to GS/CS (375/300 mg) or 50?mg D-002 once daily for 12 weeks. Symptoms were assessed by the Western Ontario and McMaster Individual Osteoarthritis Index (WOMAC) and the visual analogy scale (VAS) scores. The primary outcome was the reduction of the total WOMAC score. Secondary outcomes included WOMAC pain, stiffness and function scores, VAS score and rescue medication consumption.RESULTS: Of 60 randomized patients, 59 completed the study. D-002 and GS/SC reduced significantly total WOMAC score (72.1% and 78.5%, respectively), and pain, joint stiffness and physical function scores versus baseline. VAS scores decreased significantly with D-002 (76.6%) and GS/SC (76.8%). The reductions, significant from the second week, were enhanced over the trial. Rescue medications were consumed by 3/30 D-002 and 4/30 GS/SC patients. No differences between groups were found. Treatments were well tolerated.CONCLUSIONS: D-002 (50 mg/day) administered for 12 weeks was safe and comparable to GS/SC for alleviating OA symptoms (pain, stiffness, and functional limitation) (RPCEC00000180).

Gold nanoparticles deposited on an α-Fe2O3 substrate were prepared by different procedures including the deposition–precipitation in presence of urea or NaOH, and by the traditional wet impregnation followed by calcination. Metal loading and catalyst structures were determined by ICP-MS and XRD analyses while the size and electronic nature of Au nanoparticles were assessed using TEM and XPS. The effect of the catalyst preparation methodology was evaluated in the catalytic hydrogenation of nitrobenzene (NB) carried out in a batch reactor at 25 °C and 20 bar of H2 pressure. Among the catalysts studied, 1.0%Au/α-Fe2O3 prepared by deposition–precipitation with urea recorded the best performance (TOF = 4.6 s−1) and a selectivity toward aniline of 92%. The XRD and TEM data pointed out that the active sites are small gold particles (3.8 nm) highly dispersed on the substrate surface. Moreover, the effect of Au loading (0.5, 1.0 and 2.0 wt.%) was investigated in the hydrogenation reaction of o-, m- and p-chloronitrobenzene (o, m- and p-CNB) to o-, m- and p-chloroaniline (o-, m- and p-CAN) (a batch reactor; T = 25 °C; P = 20 bar of H2) over Au/α-Fe2O3 catalysts prepared by deposition–precipitation with urea. Regardless of the CNB isomer, maximum activity was recorded for the catalyst with 0.5 wt.% Au loading (m-CNB conversion of 99.7%). At 6 h reaction time, the yields of o-CAN, m-CAN and p-CAN were 97, 93.7 and 91.7 mol.%, respectively. Catalytic activity decreases in the order: m-CNB > o-CNB > p-CNB, but this sequence does not depend on the Au loading. Other factors such as the electronic properties of Au nanoparticles and steric factors of Cl substitute appear to play a major role in the reaction., The authors thank the Project FONDECYT 1100259 for funding this research. C. Torres and C.H. Campos are grateful to CONICYT for their doctoral fellowship.

The effect of the chlorine content and the addition of Re on the surface and catalytic properties for the liquid phase hydrogenation of cinnamaldehyde on Ir/γ-Al2O3 catalysts were studied. The results show that the increase in the amount of chlorine ions and the presence of Re modified the catalytic behavior improve the formation of cinnamyl alcohol.