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The cobalt-promoted MoS2 microspheres have been synthesized by hydrothermal methods using sodium molybdate precursors. Scanning electron microscopy indicates that spherical shape morphology and cobalt atoms are detected at MoS2 edges corresponding to (101)-plane as revealed by Cs-corrected transmission electron microscopy. The magnetic states were measured by magnetization curves obtaining a 0.044 emu/g due to paramagnetic contribution. Furthermore, the electronic structure from the density of states for 2H-MoS2 with and without cobalt at the (101) edge plane possesses a magnetic property with a value of 0.16 μB attributed to broken symmetry. [ABSTRACT FROM AUTHOR]

This study presents the synthesis and characterization of the Co supported on CeO2 nanorods (NR) catalyst to investigate catalytic performance towards efficient hydrogen production. The catalyst was characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Temperature-programmed reduction measurements showed that the Co/CeO2-NR active phase was reduced below 500°C. Adding Co to CeO2-NR enhances the basicity of the raw CeO2-NR and greatly improves the conversion to 70% for CO2 and 55% for CH4. In addition, density functional theory calculations using Halgren–Lipscomb indicate electron donation from Co to CeO2-NR promotes feasible breaking of C–H bonds. [ABSTRACT FROM AUTHOR]

The utilization of edible insects (EIs) as an alternative source of nutrients and functional foods has gained substantial recognition in recent years, opening doors to sustainable food production, improved dietary health, and unique food experiences. EIs are rich in bioactive compounds (BACs) encompassing proteins, peptides, PUFA, vitamins, and antioxidants. These BACs have a wide array of health-enhancing qualities, from antioxidant, anti-inflammatory, antimicrobial and immune system-modulating effects. Furthermore, the potential of EIs extends to the management or mitigation of health conditions like obesity, diabetes, cardiovascular diseases, and malnutrition. The incorporation of EIs into food systems has evolved beyond traditional consumption, with applications in the development of functional foods, dietary supplements, and food ingredients. In this context, this critical review aims to amalgamate the most recent developments in the realm of EIs-based food products, in addition to elucidating the most efficient process intensification procedures for the extraction and recovery of these BACs. The sustainable utilization of EIs calls for a careful examination of several crucial considerations, including consumer acceptance or allergenicity. In this respect, intensified technologies have emerged to maximize the potential of BACs derived from EIs, while simultaneously enhancing their functionality, stability, and regulatory approval within the ambit of food products. [ABSTRACT FROM AUTHOR]

Edible Insects (EIs) are an alternative source of bioactive compounds such as proteins or fatty acids and micronutrients as vitamins or minerals, thus showing potential to replace traditional foodstuffs in an economical and environmentally friendly way. Nonetheless, EIs can accumulate hazardous chemicals such as mycotoxins and heavy metals. The aim of the present study is to determine mycotoxins and heavy metal content in raw insect samples and those resulting products obtained after supercritical fluid extraction (SFE). Insect samples included Acheta domesticus (cricket) meal, Tenebrio molitor (mealworm) meal, Alphitobius diaperinus (buffalo worm), and Locusta migratoria (locust). For this purpose, a QuEChERS method followed by LC-MS/MS analysis was optimized with good results for the analysis of mycotoxins, principally Aflatoxins (AFs), Ochratoxin A (OTA), and Enniatins (ENNs). In contrast, heavy metals (As, Cd, Hg, Pb) were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results obtained revealed that Locust was positive for AFG2 at a level of 115.5 μg/kg, and mealworm was only contaminated with OTA at 58.1 μg/kg. Emerging mycotoxins (ENNA, ENNA1, ENNB, and ENNB1) were detected at lower levels < 2.2 µg/Kg. Concerning heavy metals, limits exceeding regulation were detected for Cd in the insect species studied, with levels up to 219 μg/kg, and for Pb in crickets (100.3 μg/kg). Finally, the analysis of the post-extraction solids after SFE processing revealed that heavy metals remained in the resulting SFE cakes, while mycotoxins were detected at negligible levels (up to 1.3 µg/Kg). [ABSTRACT FROM AUTHOR]

Vandenboschia speciosa is an endangered tetraploid fern species with a large genome (10.5 Gb). Its geographical distribution is characterized by disjoined tertiary flora refuges, with relict populations that survived past climate crises. Here, we analyzed the transposable elements (TEs) and found that they comprise approximately 76% of the V. speciosa genome, thus being the most abundant type of DNA sequence in this gigantic genome. The V. speciosa genome is composed of 51% and 5.6% of Class I and Class II elements, respectively. LTR retrotransposons were the most abundant TEs in this species (at least 42% of the genome), followed by non-LTR retrotransposons, which constituted at least 8.7% of the genome of this species. We introduce an additional analysis to identify the nature of non-annotated elements (19% of the genome). A BLAST search of the non-annotated con-tigs against the V. speciosa TE database allowed for the identification of almost half of them, which were most likely diverged sequence variants of the annotated TEs. In general, the TE composition in V. speciosa resembles the TE composition in seed plants. In addition, repeat landscapes revealed three episodes of amplification for all TEs, most likely due to demographic changes associated with past climate crises. Key words: climate crisis, demographic changes, endangered species, ferns, genome size, relict populations, tetraploidy, transposable elements, Vandenboschia speciosa. Le Vandenboschia speciosa est une espece menacee de fougere tetraploide a grand genome (10,5 Gb). Sa repartition geographique se caracterise par des refuges floraux tertiaires disjoints, avec des populations reliques qui ont survecu a des crises climatiques anterieures. Dans ce travail, les auteurs analysent les elements transpos-ables (TE) et rapportent qu'ils constituent environ 76 % du genome du V. spieciosa, ils representent ainsi le type de sequence d'ADN le plus abondant dans ce genome gigantesque. Le genome du V. spieciosa est compose a 51 % et a 5,6 % respectivement d'elements de Classe I et de Classe II. Les retrotransposons a LTR etaient les TE les plus abond-ants chez cette espece (au moins 42 % de genome), suivis des retrotransposons non-LTR, lesquels constituaient aumoins 8,7 % du genome de cette espece. Les auteurs ont realise une analyse additionnelle pour identifier la nature des elements non-annotes (19 % du genome). Une analyse BLAST des contigs non-annotes contre une base de don-nees des TE du V. spieciosa a permis d'en identifier pres de la moitie, lesquels constituent vraisemblablement des variants divergents par rapport aux TE annotes. De maniere generale, la composition en TE du V. speciosa ressem-ble a la composition rencontree chez les plantes a graines. De plus, cette caracterisation des sequences repetees suggere que trois episodes d'amplification de tous les TE se seraient produits, vraisemblablement en raison de changements demographiques associes aux crises climatiques passees. Mots-cles: crise climatique, changements demographiques, espece menacees, fougeres, taille du genome, populations reliques, tetraplo'idie, elements transposables, Vandenboschia speciosa., Introduction Transposable elements (TEs) are ubiquitous components of eukaryotic genomes that are considered drivers of genome evolution (Bohne et al. 2008; Belyayev 2014; Bourque et al. 2018), and have a [...]