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Biologists and engineers are making tremendous efforts in contributing to a sustainable and green society. To that end, there is growing interest in waste management and valorisation. Lignocellulosic biomass (LCB) is the most abundant material on the earth and an inevitable waste predominantly originating from agricultural residues, forest biomass and municipal solid waste streams. LCB serves as the renewable feedstock for clean and sustainable processes and products with low carbon emission. Cellulose and hemicellulose constitute the polymeric structure of LCB, which on depolymerisation liberates oligomeric or monomeric glucose and xylose, respectively. The preferential utilization of glucose and/or absence of the xylose metabolic pathway in microbial systems cause xylose valorization to be alienated and abandoned, a major bottleneck in the commercial viability of LCB-based biorefineries. Xylose is the second most abundant sugar in LCB, but a non-conventional industrial substrate unlike glucose. The current review seeks to summarize the recent developments in the biological conversion of xylose into a myriad of sustainable products and associated challenges. The review discusses the microbiology, genetics, and biochemistry of xylose metabolism with hurdles requiring debottlenecking for efficient xylose assimilation. It further describes the product formation by microbial cell factories which can assimilate xylose naturally and rewiring of metabolic networks to ameliorate xylose-based bioproduction in native as well as non-native strains. The review also includes a case study that provides an argument on a suitable pathway for optimal cell growth and succinic acid (SA) production from xylose through elementary flux mode analysis. Finally, a product portfolio from xylose bioconversion has been evaluated along with significant developments made through enzyme, metabolic and process engineering approaches, to maximize the product titers and yield, eventually empowering LCB-based biorefineries. Towards the end, the review is wrapped up with current challenges, concluding remarks, and prospects with an argument for intense future research into xylose-based biorefineries., Biologists and engineers are making tremendous efforts in contributing to a sustainable and green society.

The tap water quality in Peru fails to meet the World Health Organization (WHO) drinking water standards; consequently, the local population in Peru has been exposed over the last few years to harmful arsenic levels through water consumption. A field study was conducted in Peru between 2019 and 2020 using granular adsorbers and hybrid membranes based on the technology using milk protein nanofibril–carbon hybrid materials previously introduced in the literature by us (S. Bolisetty and R. Mezzenga, Nat. Nanotechnol., 2016, 11, 365). The performance was analyzed across 28 households as well as 3 community-based water treatment plants in some of the Peruvian arsenic burdened regions, covering a range of groundwater arsenic concentrations between 11 μg L−1 and 1.1 mg L−1. Three different kinds of filtration units were installed including the combined granular media and hybrid membrane (type I), hybrid membrane alone (type II), and granular media (type III), to determine the effectiveness of different filtration setups for arsenic removal in different regions. The arsenic removal by household filtration units and community filtration units shows a removal efficiency exceeding 99% at various initial arsenic concentrations for a duration up to nine months. In addition, it is shown that an aqueous NaOH solution can be used to regenerate the adsorbent, extending its operational lifetime and the overall capacity for As removal. High purification efficiency, very low cost, safety, little to no energy requirement, possibility of regeneration and simplicity of operation make this technology suitable for arsenic removal from drinking water in a broad range of urban and rural areas., Environmental Science: Water Research & Technology, 7 (12), ISSN:2053-1400, ISSN:2053-1419

Marine fish industries discard huge amounts of fish waste every year, which in turn impose problems of environmental pollution and loss of economic value. About 75% of the total weight of fish is discarded in the form of skins, bones, fins, heads, guts, and scales, which contain high levels of collagen type I. Generally, major sources for commercial collagens are the skin and bone of pigs and cows; however, these sources are chiefly associated with the risk of transference of zoonotic diseases or religious issues. Traditional protocols applied to the extraction of collagen are outdated, mainly with respect to present demands to develop more sustainable processes. This work explores the use of sustainable solvents, such as deep eutectic solvents (DES), to develop a more efficient, cost-effective and biocompatible process to extract collagen from waste from the fish industry waste. The extraction of collagen from the skin of Atlantic cod (Gadus morhua) using aqueous solutions of various eutectic solvents was studied, and after selection of the best solvent, an aqueous solution of urea (U) and lactic acid (LA) at a molar ratio of 1 : 2 (U : LA 1 : 2), the collagen extracted was properly characterized using SDS-PAGE, CD, FTIR, and XRD, and shown to be of type I. The results obtained here demonstrate an improvement in the yield and quality of the extracted collagen when eutectic mixtures were applied instead of acetic acid. After optimization of the process conditions, a maximum extraction yield of 6% was obtained for the aqueous solution of U : LA 1 : 2 at 0.75 M. The present work demonstrates the potential use of codfish skin waste and an aqueous solution of a DES to develop a more environmentally-friendly process to obtain high-quality collagen type I. It is an effort to convince industries to valorize their own residues under the guidelines of a circular economy published

The environmental and economic challenges currently faced by the wax market may be addressed by the use of sustainable bio-based alternatives. Hereto, ketonization of vegetable oils and animal fats is a potential clean reaction route towards ketone bio-waxes. In the presence of a heterogeneous TiO2 catalyst, palm fatty acid distillate (PFAD) and other commercial feedstock are selectively coupled to bio-waxes in a solvent-less liquid phase ketonization process. The resulting ketone bio-waxes show similar, if not better water repellence properties than the current benchmark paraffin waxes when tested as hydrophobization agents in aqueous wax emulsions for wood composite materials. Despite the efficient utilization of biomass carbon in accord with the prescribed Green Chemistry principles in the catalytic ketonization reaction, sustainable end products are not always guaranteed. Depending on the substrate and system scenario, the comparative life cycle assessment (LCA) shows significantly lower or higher carbon footprints in comparison to fossil paraffin. Cultivation of biomass feedstock, catalyst production and the end-of-life phase are identified as the three major hotspots in the life cycle, while the gate-to-gate impact of the proposed ketonization process design itself is rather limited. Advice is formulated to considerably improve LCA of ketone bio-waxes, achieving sustainable waxy products with appreciably lower CO2 footprints than the fossil paraffin waxes.

Over the last few decades extensive research gave unambiguous evidence for the endocrine disrupting nature of bisphenol A (BPA), which has been an indispensable precursor in polymer chemistry since 1946. Unfortunately, current alternatives (e.g., bisphenol F and bisphenol S), are as endocrine active as BPA, emphasizing the need for a more multidisciplinary approach to design BPA alternatives, including a preliminary toxicity screening of the endocrine disrupting character in addition to performance screening. Moreover, the current topical transition towards a circular- and bio-economy stresses to adopt renewable resources to produce future chemicals and materials. To enable, inspire and stimulate the design of safer, functional and renewable BPA alternatives, this review gathered all research concerning bio-based bisphenol structures, their performance and in vitro oestrogenic activity. As a key structural feature providing high-performance polymer properties, only bio-based bisphenols with a diphenylmethane core scaffold, published in peer-reviewed papers, were included in this study. This focus revealed valuable structure–property and structure–toxicity relationships, providing the fundament for rational design of safe bisphenols.

This work is part of the doctoral thesis of Lida Yaneth Maldonado-Mateus conducted within the context of the "Program of Nutrition and Food Sciences" at the University of Granada. This work was supported by the "Plan propio de Investigacion y Transferencia" of the University of Granada under both programs "Intensificacion de la Investigacion, modalidad B" granted to Jose A. Rufian-Henares and the postdoctoral program "Perfeccionamiento de Doctores" in the case of Sergio Perez-Burillo, and by the European Research Commission (Research Executive Agency) under the research project Stance4Health under a grant (Contract No. 816303) to Jose A. Rufian-Henares., Cocoa is a highly consumed food with beneficial effects on human health. Cocoa roasting has an important influence on its sensory and nutritional characteristics; therefore, roasting could also play a role in cocoa bioactivity. Thus, the aim of this paper is to unravel the effect of cocoa roasting conditions on its antioxidant capacity and modifications of gut microbiota after in vitro digestion-fermentation. HMF and furfural, chemical markers of non-enzymatic browning, were analyzed in unroasted and roasted cocoa powder at different temperatures, as well as different chocolates. The antioxidant capacity decreased with roasting, most probably due to the loss of phenolic compounds during heating. In the case of the evaluated chocolates, the antioxidant capacity was 2–3 times higher in the fermented fraction. On the other hand, HMF and furfural content increased during roasting due to increasing temperatures. Moreover, unroasted and roasted cocoa powder have different effects on gut microbial communities. Roasted cocoa favored butyrate production, whereas unroasted cocoa favored acetate and propionate production in a significant manner. In addition, unroasted and roasted cocoa produced significantly different gut microbial communities in terms of composition. Although many bacteria were affected, Veillonella and Faecalibacterium were some of the most discriminant ones; whereas the former is a propionate producer, the latter is a butyrate producer that has also been linked to positive effects on the inflammatory health of the gut and the immune system. Therefore, unroasted and roasted cocoa (regardless of the roasting temperature) promote different bacteria and a different SCFA production., "Plan propio de Investigacion y Transferencia" of the University of Granada, European Research Commission (Research Executive Agency) under the research project Stance4Health 816303

Age determination of minerals using the U–Pb technique is widely used to quantify time in Earth's history. A number of geochronology laboratories produce the highest precision U–Pb dates employing the EARTHTIME 202Pb–205Pb–233U–235U tracer solution for isotope dilution, and the EARTHTIME ET100 and ET2000 solutions for system calibration and laboratory intercalibration. Here, we report ET100 and ET2000 solution data from the geochronology laboratory of University of Geneva obtained between 2008 and 2021 and compare the most recent data with results from the geochronology laboratories of Princeton University and ETH Zürich. This compilation demonstrates that (i) the choice of the thermal ionization mass spectrometer model has no influence on precision and accuracy of the data; (ii) the often observed excess scatter of apparent ET100 solution 206Pb/238U dates can be mitigated by more careful tracer-sample equilibration; and (iii) natural zircon reference materials are not suitable for evaluating intra-laboratory repeatability and inter-laboratory reproducibility, since they combine several phenomena of natural system complexities (especially domains of different age within the same zircon grain, and residual loss of radiogenic lead in domains of high decay damage after chemical abrasion pre-treatment). We provide our best estimates of apparent dates for the ET100 solution (206Pb/238U date, 100.173 ± 0.003 Ma), for ET2000 solution (207Pb/206Pb date, 1999.935 ± 0.063 Ma), as well as for natural reference zircon Temora-2 (206Pb/238U date, 417.353 ± 0.052 Ma). These data will allow U–Pb laboratories to evaluate their analytical performance and to independently calibrate non-EARTHTIME tracer solutions in use., This paper presents U, Pb isotopic data of synthetic EARTHTIME solutions and natural reference materials together with suggestions how to ensure long-term intra- and inter-laboratory reproducibility of high-precision TIMS U–Pb geochronology.

This paper describes a straightforward electrochemical method for rapid and robust urinary microRNA (miRNA) quantification using disposable biosensors that can discriminate between urine from diabetic kidney disease (DKD) patients and control subjects. Aberrant miRNA expression has been observed in several major human disorders, and we have identified a urinary miRNA signature for DKD. MiRNAs therefore have considerable promise as disease biomarkers, and techniques to quantify these transcripts from clinical samples have significant clinical and commercial potential. Current RT-qPCR-based methods require technical expertise, and more straightforward methods such as electrochemical detection offer attractive alternatives. We describe a method to detect urinary miRNAs using diazo sulfonamide-modified screen printed carbon electrode-based biosensors that is amenable to parallel analysis. These sensors showed a linear response to buffered miR-21, with a 17 fM limit of detection, and successfully discriminated between urine samples (n = 6) from DKD patients and unaffected control subjects (n = 6) by differential miR-192 detection. Our technique for quantitative miRNA detection in liquid biopsies has potential for development as a platform for non-invasive high-throughput screening and/or to complement existing diagnostic procedures in disorders such as DKD., In this study we have developed an electrochemical microRNA biosensor sensitive to 17 fM and capable of detecting an established downregulation of urinary miR-192 in diabetic kidney disease patients.