Solid-phase extraction/MALDI-MS: extended ion-pairing surfaces for the on-target cleanup of protein samples.

The surface of a matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) target can be covalently modified so that it behaves like a medium for solid-phase extraction (SPE). These modified targets are capable of binding molecules of interest, but not contaminants, from sample solutions placed on them. This allows the analyte to be cleaned up on the probe surface by simply washing the target to remove the contaminants prior to MALDI-MS analysis. A limitation of the current SPE/MALDI-MS targets is that they have a fairly low binding capacity, since the coating on these targets is based upon self-assembled monolayers (SAMs). To overcome this limitation, we have investigated new surface coatings for SPE/MALDI-MS that will have a higher binding capacity than targets modified with SAMs. Here, we describe the development of new SPE/MALDI-MS surfaces that have very high molecular weight (> 300,000) polylysine chains attached to them. Targets modified in this manner are capable of binding peptides/proteins by ion-pairing interactions and have approximately 100 times the binding capacity of the SAM-based targets. Furthermore, these polylysine targets can capture over 60% of a protein from a highly contaminated solution. Consequently, polylysine SPE/MALDI-MS targets offer a practical solution for analyzing very small volumes (< 1 microL) of peptide/protein solutions contaminated with high levels of inorganic salts, buffers, detergents, chaotropic agents, and other solubilizing agents.     

Glycerolysis of Soybean Oil with Crude Glycerol Containing Residual Alkaline Catalysts from Biodiesel Production

The glycerolysis reaction of soybean oil was evaluated using crude glycerol obtained from the transesterification of soybean oil with methanol, catalyzed by sodium methoxide and sodium hydroxide, without any purification step other than the methanol removal. Crude glycerol with the lower content of remaining inorganic catalyst produced the highest concentration of monoglycerides (about 42%). The effect of the addition of water on the glycerolysis reaction was analyzed, evidencing a low formation rate of products in the first stages of the reaction due to the transformation of the inorganic catalyst to soaps, which are weaker bases. The sample of crude glycerol that led to the best results was evaluated at several temperatures. It was observed that the reaction with crude glycerol exhibits a lower formation rate of monoglycerides at low temperatures (160 and 180 °C) compared with the reaction with pure glycerol and catalyzed with NaOH. This behavior was explained by the lower activity of the soaps present in the crude glycerol respect to the inorganic base. Above 200 °C the reaction is very fast and the monoglycerides formed are consumed to produce diglycerides.     

Sprague Dawley Rats Show More Severe Bone Loss,Osteophytosis and Inflammation Compared to Wistar Han Rats in a High-Fat,High-Sucrose Diet Model of Joint Damage

In animal models, joint degeneration observed in response to obesogenic diet varies in nature and severity. In this study, we compare joint damage in Sprague Dawley and Wistar-Han rats in response to a high-fat, high-sucrose (HFS) diet groove model of osteoarthritis (OA). Wistar Han (n = 5) and Sprague Dawley (n = 5) rats were fed an HFS diet for 24 weeks. OA was induced 12 weeks after the diet onset by groove surgery in the right knee joint. The left knee served as a control. Outcomes were OARSI histopathology scoring, bone changes by µCT imaging, local (synovial and fat pad) and systemic (blood cytokine) inflammation markers. In both rat strains, the HFS diet resulted in a similar change in metabolic parameters, but only Sprague Dawley rats showed a large, osteoporosis-like decrease in trabecular bone volume. Osteophyte count and local joint inflammation were higher in Sprague Dawley rats. In contrast, cartilage degeneration and systemic inflammatory marker levels were similar between the rat strains. The difference in bone volume loss, osteophytosis and local inflammation suggest that both rat strains show a different joint damage phenotype and could, therefore, potentially represent different OA phenotypes observed in humans.     

Crop residues: applications of lignocellulosic biomass in the context of a biorefinery

Interest in lignocellulosic biomass conversion technologies has increased recently because of their potential to reduce the dependency on non-renewable feedstocks. Residues from a variety of crops are the major source of lignocellulose, which is being produced in increasingly large quantities worldwide. The commercial exploitation of crop residues as feedstocks for biorefineries which could be used to produce a variety of goods such as biofuels, biochemicals, bioplastics, and enzymes is an attractive approach not only for adding value to residues but also for providing renewable products required by the expanding bioeconomy market. Moreover, the implementation of biorefineries in different regions has the potential to add value to the specific crop residues produced in the region. In this review, several aspects of crop residue application in biorefineries are discussed, including the role of crop residues in the bioeconomy and circular economy concepts, the main technical aspects of crop residue conversion in biorefineries, the main crop residues generated in different regions of the world and their availability, the potential value-added bioproducts that can be extracted or produced from each crop residue, and the major advantages and challenges associated with crop residue utilization in biorefineries. Despite their potential, most biomass refining technologies are not sufficiently advanced or financially viable. Several technical obstacles, especially with regard to crop residue collection, handling, and pre-treatment, prevent the implementation of biorefineries on a commercial scale. Further research is needed to resolve these scale-up-related challenges. Increased governmental incentives and bioeconomic strategies are expected to boost the biorefinery market and the cost competitiveness of biorefinery products.     

Inactivation of Colletotrichum gloeosporioides spores by high hydrostatic pressure combined with citral or lemongrass essential oil

Anthracnose, caused by the fungus Colletotrichum gloeosporioides, is the main post-harvest disease of the papaya. Inactivation of the spores of C. gloeosporioides in saline solution by the use of high hydrostatic pressure, citral oil and lemongrass oil, alone and in combination, was studied. C. gloeosporioides spores were efficiently inhibited after a pressure treatment of 350 MPa for 30 min. When C. gloeosporioides was treated with 0.75 mg ml(-1) of citral or lemongrass oil, the pressure needed to achieve the same spore inhibition was 150 MPa. This work suggests the use of high hydrostatic pressure and plant essential oils as an alternative control for fruit diseases.     

Insulative Biobased Glaze from Wood Laminates Obtained by Self-Adhesion

The combination of optical transparency and mechanical strength is a highly desirable attribute of wood-based glazing materials. However, such properties are typically obtained by impregnation of the highly anisotropic wood with index-matching fossil-based polymers. In addition, the presence of hydrophilic cellulose leads to a limited water resistance. Herein, this work reports on an adhesive-free lamination that uses oxidation and densification to produce transparent all-biobased glazes. The latter are produced from multilayered structures, free of adhesives or filling polymers, simultaneously displaying high optical clarity and mechanical strength, in both dry and wet conditions. Specifically, high values of optical transmittance (≈85.4%), clarity (≈20% with low haze) at a thickness of ≈0.3 mm, and highly isotropic mechanical strength and water resistance (wet strength of ≈128.25 MPa) are obtained for insulative glazes exhibiting low thermal conductivity (0.27 W m⁻¹ K⁻¹, almost four times lower than glass). The proposed strategy results in materials that are systematically tested, with the leading effects of self-adhesion induced by oxidation rationalized by ab initio molecular dynamics simulation. Overall, this work demonstrates wood-derived materials as promising solutions for energy-efficient and sustainable glazing applications.     

A control strategy for variable-speed variable-pitch wind turbines within the regions of partial- and full-load operation without wind speed feedback

In this paper, the control of a variable-speed variable-pitch wind turbine in the whole wind speed range is addressed, without any feedback measurement of wind speed. In addition to an aerodynamic torque observer able to ensure the tracking of the maximum delivered power in the partial-load region, a novel wind speed observer is proposed for power regulation in the full-load region, along with a sliding surface ensuring finite-time set-point stabilization of the speed tracking error. The proposed control solution has been validated on the National Renewable Energy Laboratory 5-MW three-blade wind turbine model using the recognized high-fidelity simulation tool FAST.     

Super-Macroporous Lightweight Materials Templated from Bicontinuous Intra-Phase Jammed Emulsion Gels Based on Nanochitin (Small 39/2023)

Non-equilibrium multiphase systems are formed by mixing two immiscible nanoparticle dispersions, leading to bicontinuous emulsions that template cryogels with interconnected, tortuous channels. Herein, a renewable, rod-like biocolloid (chitin nanocrystals, ChNC) is used to kinetically arrest bicontinuous morphologies. Specifically, it is found that ChNC stabilizes intra-phase jammed bicontinuous systems at an ultra-low particle concentration (as low as 0.6 wt.%), leading to tailorable morphologies. The synergistic effects of ChNC high aspect ratio, intrinsic stiffness, and interparticle interactions produce hydrogelation and, upon drying, lead to open channels bearing dual characteristic sizes, suitably integrated into robust bicontinuous ultra-lightweight solids. Overall, it demonstrates the successful formation of ChNC-jammed bicontinuous emulsions and a facile emulsion templating route to synthesize chitin cryogels that form unique super-macroporous networks.     

Black Bioinks from Superstructured Carbonized Lignin Particles

A renewable source of carbon black is introduced by the processing of lignin from agro-forestry residues. Lignin side streams are converted into spherical particles by direct aerosolization followed by carbonization. The obtained submicron black carbon is combined with cellulose nanofibers, which act as a binder and rheology modifier, resulting in a new type of colloidal bioink. The bioinks are tested in handwriting and direct ink writing. After consolidation, the black bioinks display total light reflectance (%R) at least three times lower than commercial black inks (reduction from 12 to 4%R). A loading of up to 20% of nanofibers positively affects the cohesion of the dried bioink (1 to 16 MPa), with no significant reduction in light reflectance. This is a result of the superstructuring of the ink components, which disrupts particle packing, intensifies colloidal interactions, introduces light absorption, and non-reflective multiple scattering.     

Bifunctional Thiourea‐Catalyzed Asymmetric Addition of Anthrones to Maleimides

For the first time, the addition of anthrones to maleimides catalyzed by bifunctional thiourea catalysts is reported. The thiourea moiety is able to activate the maleimide and the tertiary amine deprotonates the anthrone, furnishing the final Diels–Alder or Michael adducts in excellent yields and enantioselectivities.