Hydrogen production by steam reforming of ethanol over Co/CeO2 catalysts: Effect of cobalt content

The Co/CeO₂ catalysts obtained by co-precipitation method were used in the steam reforming of ethanol (SRE). The influence of cobalt active phase content (15–29 wt%), the reaction temperature (420–600 °C) and H₂O/EtOH molar ratio (12/1 and 6/1) were examined. The physicochemical characterization revealed that the cobalt content of the catalyst influences the metal-support interaction which results in catalyst performance in SRE process. The differences between catalytic properties of the Co/CeO₂ catalysts with different metal loading in SRE process decayed at 500 °C for H₂O/EtOH = 12/1. The best performance among the tested catalysts showed the 29Co/CeO₂ catalyst with the highest cobalt content, exhibiting the highest ethanol conversion, selectivity to two most desirable products and the lowest selectivity to by-products in comparison with catalysts containing smaller amount of metal. Its catalytic properties results probably from its unique physicochemical properties, i.e this catalyst contains large amount of cobalt but the metal crystallites are relatively small. Regardless cobalt content, an increase in the water-to-ethanol molar ratio in the feed increased the concentration of hydrogen an carbon dioxide and decreased formation of carbon monoxide, acetone, aldehyde and ethylene.     

Nutritional status and its correlates in Equatorial Guinean preschool children: results from a nationally representative survey

BACKGROUND: In Equatorial Guinea, as a result of the recent growth of the oil industry, there is an opportunity to address important public health problems through public and private initiatives. To propose effective nutrition and public health strategies, it is important first to have reliable information on the nutritional status of the population and the underlying factors affecting it. OBJECTIVE: To assess the nutritional status and the prevalence of anemia among Equatoguinean children in a nationally representative sample and to identify the risk factors associated with the nutritional problems detected. METHODS: The study was a cross-sectional survey using a multistaged, stratified, cluster-selected sample. The survey included a sociodemographic, health, and dietary questionnaire and measurement of hematocrit and anthropometric features, from which nutritional indicators based on the National Center for Health Statistics (NCHS) reference and the World Health Organization (WHO) standards were calculated. Logistic regression models were used for the multivariate analysis. A total of 552 children aged 0 to 60 months were surveyed. RESULTS: The overall prevalence of stunting (< -2 height-for-age z-scores [HAZ]) was 29.7% based on the NCHS reference and 35.2% based on WHO standards; the risk factors associated with stunting were age (p < .0001), low socioeconomic status (p = .01), and fishing by a member of the household (p = .003) The prevalence of mild anemia (hemoglobin < 110 g/L) was 69.3%, and that of moderate or severe anemia (hemoglobin < 80 g/L) was 8.3%. The only significant risk factor associated with moderate to severe anemia was low household socioeducational level (p = .01). CONCLUSIONS: Stunting and anemia are public health problems in Equatorial Guinea. Integrated strategies, including fighting poverty and improving maternal education, should be undertaken.     

Evaluation of QuEChERS method for the determination of organochlorine pesticide residues in selected groups of fruits

This paper reports a method for organochlorine pesticide determination in selected fruit species where pesticide residues were extracted and cleaned using a buffered QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method, followed by GC–MS analysis. The method results showed the matrix-matched calibration curve linearity was >0.99 for all target analytes. With pesticide recovery rates (spiked at 0.008 mg kg⁻¹) ranging from 70% to 120%, and RSD values <17% for most compounds, the limit of quantification ranged from 0.001–0.013 mg kg⁻¹. Finally, the method ruggedness was further demonstrated by analysis of actual commercial fruits and baby food samples.     

A systematic review of DNA-based methods in authentication of game and less common meat species

Despite the numerous studies on food safety and authenticity, especially for meat and meat products, not enough studies have been conducted focusing exclusively on game species and other unusual meat animals. As a result of the European horse scandal, the horse is currently the target of many meat authenticity studies. With this review, we aim to present various DNA-based methods that have been used by researchers to identify, detect, and quantify game, uncommon meat animals, and wildlife species. Polymerase chain reaction (PCR) is considered the standard method for DNA analysis in meat authenticity testing. However, in this paper, we present several other methods that may or may not involve the PCR technique. For this purpose, we systematically reviewed 131 articles selected according to various criteria such as target animal species, method of analysis, year of publication, and so forth. The result of our study shows the most studied game and uncommon meat species, PCR- and non-PCR-based methods for game meat analysis, and DNA-based methods in wildlife conservation. With this study, researchers can find detailed information about frequent game species used as adulterants for regular meat products and the DNA-based techniques to identify them.     

Assessment of antimicrobial activity of coffee brewed in three different ways from different origins

The antimicrobial effect against pathogens such as Staphylococcus aureus, Enterecoccus faecalis, Listeria monocytogenes, Pseudomonas aeruginosa, Escherichia coli and Salmonella choleraesius was determined in four types of coffee (Coffea arabica L. cv. Colombia, decaffeinated cv. Colombia, cv. Ethiopia and cv. Kenya). Coffee was seen to have significant activity against the growth of food spoilage bacteria. Among the Gram-positive bacteria, coffee was strongly active against S. aureus, moderately active against L. monocytogenes and had a slightly inhibitory effect against E. faecalis. However, coffee samples were found to be less active against Gram-negative bacteria. The results show that espresso Colombia coffee has better antimicrobial activity than filter and Italian coffee with significant differences (p?<?0.05). Taking into account the origin, there were significant differences (p?<?0.05) between Kenya and decaffeinated Colombia, on the one hand, and Ethiopia and Colombia coffee, on the other, the two last showing the highest antimicrobial activity. The antimicrobial activity of the coffee from different origins studied in this paper increased with concentration. Typical coffee compounds were also analysed, and only caffeic and chlorogenic acids showed any inhibitory effect against the growth of all the analysed bacteria. The antibacterial properties of coffee means that it has a promising potential as natural food ingredient to extend the shelf life of foods such as cake, cookies or biscuits, coffee flavoured with shakes, yoghurt.     

Dynamic Changes in the Ability to Release Neutrophil ExtraCellular Traps in the Course of Childhood Acute Leukemias

Acute leukemias, the most common cancers in children, are characterized by excessive proliferation of malignant progenitor cells. As a consequence of impaired blood cell production, leukemia patients are susceptible to infectious complications—a major cause of non-relapse mortality. Neutrophil extracellular traps (NETs) are involved in various pathologies, from autoimmunity to cancer. Although aberrant NETs formation may be partially responsible for immune defects observed in acute leukemia, still little is known on the NET release in the course of leukemia. Here, we present the first comprehensive evaluation of NETs formation by neutrophils isolated from children with acute leukemia in different stages of the disease and treatment stimulated in vitro with phorbol 12-myristate 13-acetate (PMA), N-formyl-methionyl-leucyl-phenylalanine (fMLP), and calcium ionophore (CI). NETs release was measured using quantitative fluorescent method and visualized microscopically. In this setting, NETs release was significantly impaired in leukemic children both at the diagnosis and during the treatment, and full restoration of neutrophil function was achieved only after successful completion of the leukemia treatment. We suggest that neutrophil function impairment may result from both disease- and treatment-related factors. In this context, deficient innate immune response observed in acute leukemia patients may be present regardless of neutrophil count and contribute to secondary immunodeficiency observed in this population.     

The influence of brewing method on bioactive compounds residues in spent coffee grounds of different roasting degree and geographical origin

The content of bioactive compounds in spent coffee grounds (SGC) was studied. SGC were obtained from Coffea arabica beans of different roasting degrees (light and dark) and different geographical origins (Nicaragua, Columbia and Mexico) processed using four brewing methods (mocha, filtered, drip and infusion). The highest caffeine and chlorogenic acid contents were determined in filtered spent coffee extracts. All extracts of light roasted spent coffee grounds showed lower browning index levels in comparison to that from dark roasted spent coffee grounds. Generally, the highest content of total polyphenolic compounds and highest antioxidant capacity were determined in extracts prepared in drip. In conclusion, the results obtained in this study indicate that the spent coffee grounds produced of domestic levels, especially those obtained from filter coffeemaker, could be considered as a good source of natural antioxidants.     

Use of Fourier-Transform Infrared Spectroscopy (FT-IR) for Monitoring Experimental Helicobacter pylori Infection and Related Inflammatory Response in Guinea Pig Model

Infections due to Gram-negative bacteria Helicobacter pylori may result in humans having gastritis, gastric or duodenal ulcer, and even gastric cancer. Investigation of quantitative changes of soluble biomarkers, correlating with H. pylori infection, is a promising tool for monitoring the course of infection and inflammatory response. The aim of this study was to determine, using an experimental model of H. pylori infection in guinea pigs, the specific characteristics of infrared spectra (IR) of sera from H. pylori infected (40) vs. uninfected (20) guinea pigs. The H. pylori status was confirmed by histological, molecular, and serological examination. The IR spectra were measured using a Fourier-transform (FT)-IR spectrometer Spectrum 400 (PerkinElmer) within the range of wavenumbers 3000–750 cm⁻¹ and converted to first derivative spectra. Ten wavenumbers correlated with H. pylori infection, based on the chi-square test, were selected for a K-nearest neighbors (k-NN) algorithm. The wavenumbers correlating with infection were identified in the W2 and W3 windows associated mainly with proteins and in the W4 window related to nucleic acids and hydrocarbons. The k-NN for detection of H. pylori infection has been developed based on chemometric data. Using this model, animals were classified as infected with H. pylori with 100% specificity and 97% sensitivity. To summarize, the IR spectroscopy and k-NN algorithm are useful for monitoring experimental H. pylori infection and related inflammatory response in guinea pig model and may be considered for application in humans.     

Alternating Cationic-Hydrophobic Peptide/Peptoid Hybrids: Influence of Hydrophobicity on Antibacterial Activity and Cell Selectivity

The influence of hydrophobicity on antibacterial activity versus the effect on the viability of mammalian cells for peptide/peptoid hybrids was examined for oligomers based on the cationic Lys-like peptoid residue combined with each of 28 hydrophobic amino acids in an alternating sequence. Their relative hydrophobicity was correlated to activity against both Gram-negative and Gram-positive species, human red blood cells, and HepG2 cells. This identified hydrophobic side chains that confer potent antibacterial activity (e. g., MICs of 2–8 μg/mL against E. coli) and low toxicity toward mammalian cells (<10 % hemolysis at 400 μg/mL and IC₅₀>800 μg/mL for HepG2 viability). Most peptidomimetics retained activity against drug-resistant strains. These findings corroborate the hypothesis that for related peptidomimetics two hydrophobicity thresholds may be identified: i) it should exceed a certain level in order to confer antibacterial activity, and ii) there is an upper limit, beyond which cell selectivity is lost. It is envisioned that once identified for a given subclass of peptide-like antibacterials such thresholds can guide further optimisation.