Advances in bioresource technology towards carbon neutrality

Abstrac

Lipase production and purification by self-buffering ionic liquid-based aqueous biphasic systems

n this work, a group of Good’s buffer ionic liquids (GB-ILs) comprised of tetrabutylammonium, tetra- butylphosphonium and cholinium cations paired with Good’s buffer (GB) anions (MOPSO, BES and TAPSO) was studied. Their distinctive capability to induce the formation of aqueous biphasic systems (ABS) with the salts K3PO4, K2CO3, and (NH4)2SO4, and the polymers poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), and PEG-PPG copolymers was demonstrated. Their application as purification tools to recover a lipase produced via submerged fermentation by Burkholderia cepacia ST8 was investigated. The lipase was preferentially partitioned towards the GB-IL-rich phase in both the GB-IL + salt and polymer + GB-IL purification systems. Molecular docking studies were performed aiming at to understand the possible interactions between the GB-IL ions and the lipase residues. Furthermore, the selected GB-IL-based ABS was investigated as part of an integrated process developed to successfully recover and purify an extracellular B. cepacia ST8 lipase from the fermentation broth, in which a purification factor of 22.4 ± 0.7 and a recovery yield of (94.0 ± 0.2) % were achieved.publishe

Gravity localization on thick branes: a numerical approach

We introduce a numerical procedure to investigate the spectrum of massive modes and its contribution for gravity localization on thick branes. After considering a model with an analytically known Schroedinger potential, we present the method and discuss its applicability. With this procedure we can study several models even when the Schroedinger potential is not known analytically. We discuss both the occurrence of localization of gravity and the correction to the Newtonian potential given by the massive modes.Comment: 22 pages, 12 figure

Treatment for Landfill Leachate via Physicochemical Approaches: An Overview

Leachate waste consists of various mixtures of organic, inorganic, and heavy metal contaminants, which are responsible for groundwater and surface water contamination. Landfills apply physical, chemical, and biological processes for the treatment of leachate. Most studies on leachate treatment by coagulation and flocculation are based on the selection and performance of natural based biopolymers in comparison with various inorganic metal salts and grafted polymers used for the removal of contaminants. In addition, adsorption processes utilizing non-conventional activated carbons as absorbents are the current emerging focus of the researchers in leachate treatment. These adsorbents are low-in-cost, efficient, and renewable compared to conventional adsorbents. The present paper aimed to evaluate and review the technology utilising various greener approaches in coagulation, flocculation, and adsorption as the physicochemical approaches to leachate treatment. The challenges and future work regarding the development of these green products in the commercial markets were comprehensively evaluated. This work is licensed under a Creative Commons Attribution 4.0 International License

Using entanglement improves precision of quantum measurements

We show how entanglement can be used to improve the estimation of an unknown transformation. Using entanglement is always of benefit, in improving either the precision or the stability of the measurement. Examples relevant for applications are illustrated, for either qubits and continuous variable

Evaluating Self-buffering Ionic Liquids for Biotechnological Applications

A new range of Good’s buffer ionic liquids (GB-ILs), displaying simultaneously the properties of ionic liquids and Good’s buffers, were synthesized by combination of Good’s buffers anions (MOPSO, BES, TAPSO and CAPSO) and tetrabutylammonium, tetrabutylphosphonium and cholinium cations via an acid-base neutralization reaction. The activity and stability of a lipolytic enzyme from Pseudomonas cepacia in aqueous solutions of these buffers were evaluated and the results show their advantage as media for enzymatic reactions when compared to conventional phosphate buffers. Moreover aqueous biphasic systems (ABS) composed by these GB-ILs and potassium citrate were investigated and shown to be highly effective and selective for the partitioning of the lipolytic enzyme into the GB-IL-rich phase. The results allow the development of an efficient and biocompatible process combining the self-buffering and enzyme-stabilizing properties of the GB-ILs in the reaction step, with the advantages of GB-ILs as extraction solvents in ABS

Progress and Recent Trends in the Application of Nanoparticles as Low Carbon Fuel Additives—A State of the Art Review

The first part of the current review highlights the evolutionary nuances and research hotspots in the field of nanoparticles in low carbon fuels. Our findings reveal that contribution to the field is largely driven by researchers from Asia, mainly India. Of the three biofuels under review, biodiesel seems to be well studied and developed, whereas studies regarding vegetable oils and alcohols remain relatively scarce. The second part also reviews the application of nanoparticles in biodiesel/vegetable oil/alcohol-based fuels holistically, emphasizing fuel properties and engine characteristics. The current review reveals that the overall characteristics of the low carbon fuel–diesel blends improve under the influence of nanoparticles during combustion in diesel engines. The most important aspect of nanoparticles is that they act as an oxygen buffer that provides additional oxygen molecules in the combustion chamber, promoting complete combustion and lowering unburnt emissions. Moreover, the nanoparticles used for these purposes exhibit excellent catalytic behaviour as a result of their high surface area-to-volume ratio—this leads to a reduction in exhaust pollutants and ensures an efficient and complete combustion. Beyond energy-based indicators, the exergy, economic, environmental, and sustainability aspects of the blends in diesel engines are discussed. It is observed that the performance of the diesel engine fuelled with low carbon fuels according to the second law of efficiency improves under the influence of the nano-additives. Our final part shows that despite the benefits of nanoparticles, humans and animals are under serious threats from the highly toxic nature of nanoparticles. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.20JCJQJC00160; Cardiff University; Universiti Tenaga Nasional: IC6-BOLDREFRESH2025This research was funded by Tianjin Science Fund for Distinguished Young Scholars, grant number 20JCJQJC00160, and the Universiti Tenaga Nasional grant no. IC6-BOLDREFRESH2025 (HCR) under the BOLD2025 Program. The APC was funded by Cardiff University

Granulation and microbial community dynamics in the chitosan-supplemented anaerobic treatment of wastewater polluted with organic solvents

The effect of chitosan on the development of granular sludge in upflow anaerobic sludge blanket reactors (UASB) when treating wastewater polluted with the organic solvents ethanol, ethyl acetate, and 1-ethoxy-2-propanol was evaluated. Three UASB reactors were operated for 219 days at ambient temperature with an organic loading rate (OLR) of between 0.3 kg COD m−3 d−1 and 20 kg COD m−3 d−1. One reactor was operated without the addition of chitosan, while the other two were operated with the addition of chitosan doses of 2.4 mg gVSS−1 two times. The three reactors were all able to treat the OLR tested with COD removal efficiencies greater than 90%. However, the time required to reach stable operation was considerably reduced in the chitosan-assisted reactors. The development of granules in the reactors with chitosan was accelerated and granules larger than 2000 μm were only observed in these reactors. In addition, these granules exhibited better physicochemical characteristics: the mean particle diameter (540 and 613 μm) was approximately two times greater than in the control reactor (300 μm), and the settling velocities exceeded 35 m h−1. The extracellular polymeric substances (EPS) in the reactors with the chitosan was found to be higher than in the control reactor. The protein-EPS content has been correlated with the granule size. The analyses of the microbial communities, performed through denaturing gradient gel electrophoresis and high-throughput sequencing, revealed that the syntrophic microorganisms belonging to genus Geobacter and the hydrogenotrophic methanogen Methanocorpusculum labreanum were predominant in the granules. Other methanogens like Methanosaeta species were found earlier in the chitosan-assisted reactors than in the control reactor

Down-Regulation of ZnT8 Expression in INS-1 Rat Pancreatic Beta Cells Reduces Insulin Content and Glucose-Inducible Insulin Secretion

The SLC30A8 gene codes for a pancreatic beta-cell-expressed zinc transporter, ZnT8. A polymorphism in the SLC30A8 gene is associated with susceptibility to type 2 diabetes, although the molecular mechanism through which this phenotype is manifest is incompletely understood. Such polymorphisms may exert their effect via impacting expression level of the gene product. We used an shRNA-mediated approach to reproducibly downregulate ZnT8 mRNA expression by >90% in the INS-1 pancreatic beta cell line. The ZnT8-downregulated cells exhibited diminished uptake of exogenous zinc, as determined using the zinc-sensitive reporter dye, zinquin. ZnT8-downregulated cells showed reduced insulin content and decreased insulin secretion (expressed as percent of total insulin content) in response to hyperglycemic stimulus, as determined by insulin immunoassay. ZnT8-depleted cells also showed fewer dense-core vesicles via electron microscopy. These data indicate that reduced ZnT8 expression in cultured pancreatic beta cells gives rise to a reduced insulin response to hyperglycemia. In addition, although we provide no direct evidence, these data suggest that an SLC30A8 expression-level polymorphism could affect insulin secretion and the glycemic response in vivo