Macromol

The MALDI-TOF mass-spectrometry was employed to analyze the structure of the reaction products of limonene, a natural terpene, and elemental sulfur, with the objective of identifying the occurrence of side processes, such as oxidative dehydrogenation, aromatization, and the Diels–Alder reaction cascade. The MALDI-TOF mass-spectrometry was demonstrated to be effective for the analysis of high-sulfur polymers obtained by the inverse vulcanization reaction, allowing for the unambiguous separation of sulfur-containing and hydrocarbon molecular fragments and the detailed characterization of macromolecular structures. By varying the ratio of sulfur (S₈) and limonene in the initial reaction system, we were able to ascertain the limiting amount of sulfur that can be covalently bonded by terpene, as well as determine the average length of polysulfide chains under the assumption of equal reactivity and complete depletion of all double bonds. The side reaction of limonene aromatization, as indicated by the MALDI-TOF spectrum of the product resulting from its interaction with elemental sulfur, was corroborated by ¹H and ¹³C NMR spectroscopy. Consequently, the registration and interpretation of MALDI-TOF spectra of inverse vulcanization products, either independently or in conjunction with the application of ¹H and ¹³C NMR spectroscopy methods, as well as the determination of the limiting number of sulfur atoms that can be bound to one molecule of an unsaturated compound, paves the way for new avenues of investigation into the structure and side reactions involved in the synthesis of high-sulfur polymers. Full article

Hydroxypropyl-β-cyclodextrin (HPβCD) is a derivatized cyclodextrin in which several H atoms on the hydroxyls of the glucose rings are substituted by 2-hydroxypropyl groups. The cyclic structure of HPβCD creates a cavity capable of totally or partially enclosing different molecules (inclusion complexes), and this capacity makes it useful in the pharmaceutical industry. Rifampicin is an antibiotic commonly used to treat tuberculosis; however, some of its properties such as its low solubility and variable bioavailability need to be improved by encapsulating it in systems such as HPβCD. The inclusion complexes formed by twelve structures of HPβCD and rifampicin with various polar and non-polar solvents are studied using molecular simulation. Diverse solvents are simulated using the zwitterionic or neutral configuration of rifampicin, and different values of relative permittivity in the electrostatic contribution to the total energy. The latter constant has little effect on the formation of inclusion complexes, whereas the type of rifampicin essentially determines the energies and configurations of the complexes. The zwitterion is located near the primary rim of HPβCD and the neutral form of rifampicin is near the secondary one. In both cases, the piperazine tail is incorporated into higher-energy complexes inside the host. Full article

Plant-derived phenolic compounds are recognized to provide several health benefits for humans, including anticancer, anti-inflammatory, and antioxidant proprieties. Their bioavailability in the human body has a significant impact on these outcomes. Their bioaccessibility and bioavailability are highly dependent on the structure and manner in which phenolics enter into the organism, through a complex food matrix, for instance, or as pure isolates. Furthermore, the bioaccessibility of phenolic compounds in the body is greatly impacted by interactions with a broad range of other macromolecules (such as proteins, lipids, dietary fibers, and polysaccharides) in food or during digestion. Encapsulation is a process that can improve bioaccessibility and bioavailability by guaranteeing coating of the active ingredients, controlled release, and targeted distribution to specific parts of the digestive system. However, this field has not yet received enough attention, due to the complex mechanisms through which phenolics act in the body. This review attempts to shed light on the results of research that has been performed on the potential and therapeutic benefits of encapsulated polyphenols in both health and disease. Full article

Agrochemical residues, including pesticides and herbicides, pose significant environmental and health risks when present in water sources. Conventional water treatment methods often fall short in effectively removing these persistent pollutants, necessitating innovative solutions. This review explores the use of polysaccharides and composite adsorbents as sustainable alternatives for agrochemical residue removal from water. Biopolymers such as chitosan, alginate, and cellulose are highlighted for their biodegradability, biocompatibility, and ability to be functionalized for enhanced adsorption performance. Recent advances in the development of composite materials incorporating nanomaterials, such as graphene, oxide, and metal oxides, have shown significant promise in enhancing the efficiency and selectivity of agrochemical adsorption. The review also addresses the fundamental mechanism of adsorption, such as electrostatic interactions, hydrogen bonding, and hydrophobic forces, that contribute to the effectiveness of these materials. Challenges associated with scalability, regeneration, and real-world applications are discussed, as well as future opportunities for integrating emerging technologies like 3D printing and machine learning into adsorbent design. Overall, polysaccharides and composites offer a promising pathway toward achieving efficient and sustainable agrochemical residue removal, with ongoing research needed to overcome current limitations and optimize their practical application in water treatment. Full article

Biopolymer blends of polylactic acid (PLA) and polybutylene adipate-co-terephthalate (PBAT) are extruded into flexible monolayer films. These blends are excellent candidates for the realization of environmentally friendly packaging applications. A necessary pre-requisite for that are appropriate tribological properties under mechanical contact. Reasonable wear resistance allows good protection of packed goods, and low friction forces reduce difficulties in stacking. In this research, mechanical embossment under high loads at room temperature was used for the modification of polymer surfaces to exhibit a significant friction reduction under dry conditions. The results particularly show a systematic decrease in the coefficient of friction for biopolymer blends containing 30 wt% and 40 wt% PBAT. FTIR was used to analyze the change in surface composition after mechanical embossing. A sophisticated FTIR calibration method revealed that the blend with 30 wt% PBAT shows a modified distribution of PBAT and PLA at the surface due to mechanical embossment. This leads to a controlled and long-lasting modification of the surface properties without a substantial change in the chemical composition of the polymer in bulk. Without the use of additional coatings, biodegradable packaging foils with improved characteristics are accessible. Full article

Bacterial quorum sensing (QS) is a critical communication process that regulates gene expression in response to population density, influencing activities such as biofilm formation, virulence, and antibiotic resistance. This study investigates the inhibitory effects of five phytochemicals—apigenin, carnosol, chlorogenic acid, quercetin, and rosmarinic acid—on the S-ribosylhomocysteinase (LuxS) enzyme, a key player in AI-2 signaling across both Gram-positive and Gram-negative bacteria. Using molecular docking studies, we identified that these phytochemicals interact with the LuxS enzyme, with apigenin, carnosol, chlorogenic acid, and rosmarinic acid binding within the substrate-binding pocket and exhibiting binding scores below −7.0 kcal/mol. Subsequent in vitro assays demonstrated that these compounds inhibited AI-2 signaling and biofilm formation in Escherichia coli MG1655 in a concentration-dependent manner. Notably, carnosol and chlorogenic acid showed the most potent effects, with IC₅₀ values of approximately 60 μM. These findings suggest that these phytochemicals may serve as potential QS inhibitors, providing a foundation for developing new anti-pathogenic agents to combat bacterial infections without promoting antibiotic resistance. Further studies are warranted to explore the therapeutic applications of these compounds in both clinical and agricultural settings. Full article

During the manufacturing of wooden musical instruments, offcut wood pieces are inevitably generated. This study explores the potential of utilizing three types of these small offcut wood pieces, mahogany, maple, and rosewood, by converting them into polyurea through liquefied wood technology by proposing a novel approach to synthesizing bio-based polyurea. This polyurea is a durable polymer, offering long-term carbon fixation and thereby contributing to environmental sustainability. In this study, various liquefaction conditions as parameters, including the temperature, sulfuric acid content, mix solvent ratio, and liquefaction time, were investigated in relation to polyurea film properties. The relationship between the mechanical and thermal properties of the resulting films and the characteristics of the liquefied product was investigated. Notably, when the hydroxyl value of the liquefied product exceeded 300, the resulting polyurea derived from the liquefied product exhibited a high tensile strength of 25 MPa. In contrast, when the hydroxyl value was below 300, the polyurea derived from the liquefied product displayed a strain value of up to 150%, alongside an increased thermal decomposition temperature. These findings suggest that the properties of polyurea can be effectively tuned by manipulating the characteristics of the liquefied product, offering a promising approach to enhancing the value of offcut wood in instrument manufacturing. Full article

Natural fiber composites have gained increasing attention due to sustainability considerations. One often neglected aspect is the potential for the mechanical recycling of such materials. In this work, we compounded injection-molded polypropylene (PP) and polylactic acid (PLA) short cellulose fiber composites with fiber shares up to 40 percent by weight. Both matrix materials were reinforced by the addition of the fibers. We investigated a trifold full recycling process, where we subjected the materials produced in the first place to compounding, injection molding, testing, and shredding, and then repeated the process. Although the materials’ properties assigned to degradation were found to decrease with progressive recycling, attractive mechanical properties could be preserved even after the third reprocessing cycle. Full article

The development and characterization of agricultural byproduct-based biocomposites are an important part of green chemistry. In this work, four-ingredient blends were formulated with the melt blending method. The set of composites (named as CSO series) was made with poly(lactic acid) (PLA) as the major matrix, washed cottonseed meal (WCSM) as a filler, cottonseed oil (CSO) as a compatibilizer, and glycerol (GLY) as a plasticizer. The morphological analysis showed the homogenous dispersion of the cottonseed byproducts into the PLA matrix to some extent. The thermogravimetric analysis revealed that thermal stability was impacted by the ingredient’s addition. The functional group analysis of the sample and simulation by Fourier transform infrared spectra confirmed the chemical interactions of PLA with WCSM in the blend products. CSO was most likely subjected to physical blending into the products. The mechanical strengths of those composites were affected by the ratios of PLA-CSO. Generally, the tensile strengths were in the range of 0.74–2.1 MPa, which indicate its suitability for low-strength biodegradable plant container development. The blend products had a lower water absorption during the water soaking test. This work shows the feasibility of incorporating cottonseed WCSM and CSO into a PLA composite for sustainable agricultural applications. Full article

The interaction of poly(trimethylene carbonate) (PTMC) with hydroxyl group compounds was investigated as a model for polymer blending with polysaccharides. While 1-butanol, 2-butanol, ethylene glycol, and 1,2-cyclohexanediol showed almost no detectable interaction with PTMC in both solution states with the ¹H NMR and solid states with the FT-IR, glucose and cellobiose suggested a slight change in the spectral pattern in FT-IR analysis. The thermal properties of the blended samples of PTMC and these hydroxyl groups were also investigated. Although the blends of PTMC with 1-butanol and 2-butanol did not influence thermal degradation behaviors due to their low boiling points, the PTMC blend with a higher number of hydroxyl groups, especially glucose and cellobiose, tended to increase thermal resistance and glass transition temperature, hence showing the existence of an interaction through hydrogen bonding. Full article

A Leuconostoc mesenteroides strain (SJC113) isolated from cheese curd was found to produce large amounts of a mucoid exopolysaccharide (EPS). An analysis revealed the glucan nature of the EPS with 84.5% (1→6)-linked α-d-glucose units and 5.6% (1,3→6)-linked α-d-glucose units as branching points. The EPS showed 52% dextranase resistance and a yield of 7.4 ± 0.9 g/L from MRS medium supplemented with 10% sucrose within 48 h. Ln. mesenteroides SJC113 was also characterized and tested for the production of EPS as a fat substitute in fresh cheese. Strain SJC113 showed high tolerance to a wide range of NaCl concentrations (2, 5 and 10%), high β-galactosidase activity (2368 ± 24 Miller units), cholesterol-reducing ability (14.8 ± 4.1%), free radical scavenging activity (11.7 ± 0.7%) and hydroxyl scavenging activity (15.7 ± 0.4%). The strain had no virulence genes and was sensitive to clinically important antibiotics such as ampicillin, tetracycline and chloramphenicol. Ln. mesenteroides SJC113 produced highly viscous EPS during storage at 8 °C in skim milk with 5% sucrose. Therefore, these conditions were used for EPS production in skim milk before incorporation into fresh cheese. Four types of fresh cheese were produced: full-fat cheese (FF) made from pasteurized whole milk, non-fat cheese (NF) made from pasteurized skim milk, non-fat cheese made from skim milk fermented with Ln. mesenteroides without added sugar (NFLn0) and non-fat cheese made from skim milk fermented with Ln. mesenteroides with 5% sucrose (NFLn5). While the NF cheeses had the highest viscosity and hardness, the NFLn5 cheeses showed lower firmness and viscosity, higher water-holding capacity and lower weight loss during storage. Overall, the NFLn5 cheeses had similar rheological properties to full-fat cheeses with a low degree of syneresis. It was thus shown that the glucan-type EPS produced by Ln. mesenteroides SJC113 can successfully replace fat without altering the texture of fresh cheese. Full article

With the world population rising, wheat straw production is expected to reach 687–740 million tons per year by 2050. Its frequent application as a fuel source leads to air, water, and soil pollution. Limited literature exists on methods for separating components of residual wheat straw. Optimal conditions for organosolv pulping of hydrolyzed wheat straw include 3% FeCl₃·6H₂O as a catalyst, a biomass-to-solvent ratio of 1:15 (m/v), and 50% ethanol:water as cooking liquor at 200 °C for 30 min. Desilication conditions involve extraction with 7.5% Na₂CO₃ at a biomass-to-solvent ratio of 1:20 (m/v) treated at 115 °C for 60 min. Lignin from hydrolyzed wheat straw showed similar properties to organosolv lignin from untreated straw, with minimal lignin alteration during hydrolysis. Hydrolysis significantly degraded cellulose. A 41% lignin recovery rate with 95% purity was achieved from pre-extracted hydrolyzed straw. Recovered cellulose after silica removal had 2% ash and 87% purity. The innovation of this process lies in the development of a comprehensive, sustainable, efficient, and economically viable biorefinery process that efficiently separates key components of wheat straw, i.e., xylose, lignin, cellulose, and silica, while addressing environmental pollution associated with its traditional use as fuel. Full article

The combination of different wood-modification technologies to obtain improved performance is increasingly receiving attention in research. In this study, Scots pine (Pinus sylvestris) sapwood was impregnated with furfuryl alcohol (FFA) in pure aqueous 20, 40, and 60% solution strength without adding any catalyst. In a second step, the FFA was polymerized while simultaneously performing thermal modification in a closed system at 130, 150, or 180 °C. After leaching and ageing tests, the nine different combinations were tested in use class 4 applications (in contact with or very close to the ground and frequently wet) according to CEN/TS 15083-2 (2005) decay laboratory test. It was noted that even the minimum-intensity combination of 20% FFA at 130 °C resulted in maximum durability class (DC) 1 performance. On the contrary, DC 4 was assigned to thermally modified control samples, even at the maximum intensity of thermal modification. Similarly, for FFA modifications, previous research has suggested that an uptake of 35% solution strength is required to obtain an adequate durability performance in use class 4 applications. High levels of resistance against termites were also noted by corresponding termite lab tests. Moisture studies showed the combined treatments resulted in improved stability and reduced moisture uptakes. Thus, the results obtained by this study revealed synergistic performance effects, which originate from the combined thermo-chemical modification approach, and which were higher than simple accumulation of the individual performance of purely thermally or chemically modified wood. Thus, the presented findings have provided positive implications for industrial applications of thermo-chemical modification techniques and offers an array of new research opportunities. Full article

Although there are numerous available immunomodulators, those of natural origin would be preferable based on their safety profile and effectiveness. The research and clinical interest in immunomodulators have increased in the last decades, especially in the immunomodulatory properties of plant-based therapies. Innovative technologies and extensive study on immunomodulatory natural products, botanicals, extracts, and active moieties with immunomodulatory potential could provide us with valuable entities to develop as novel immunomodulatory medicines to enhance current chemotherapies. This review focuses on plant-based immunomodulatory drugs that are currently in clinical studies. However, further studies in this area are of utmost importance to obtain complete information about the positive effects of medicinal plants and their chemical components and molecules as an alternative to combatting various diseases and/or prevention. Full article

This study explores the potential of cold atmospheric plasma (CAP) to facilitate the delivery of large-molecule drugs to the brain. The blood–brain barrier (BBB) restricts the passage of most drugs, hindering treatment for neurological disorders. CAP generates reactive oxygen and nitrogen species (RONS) that may disrupt the BBB’s tight junctions, potentially increasing drug permeability. An in vitro BBB model and an immortalized cell line (bEND.3) were used in this experiment. Fluorescein isothiocyanate dextran (FD-4), a model drug, was added to the cells to determine drug permeability. Custom microplasma was used to produce reactive oxygen species (ROS). Trans-endothelial electrical resistance (TEER) measurements assessed the integrity of the BBB after the CAP treatment. A decrease in TEER was observed in the CAP-treated group compared to the controls, suggesting increased permeability. Additionally, fluorescence intensity measurements from the basal side of the trans-well plate indicated higher drug passage in the CAP-treated group. Moreover, the higher presence of ROS in the plasma-treated cells confirmed the potential of CAP in drug delivery. These findings suggest that CAP may be a promising approach for enhancing brain drug delivery. Full article

Microalgae are a substantial group of unicellular prokaryotic and eukaryotic marine organisms. Due to their high protein content of 50–70%, microalgae have the potential to become a sustainable alternative protein source, as well as aiding in the development of bioactive peptide-based nutraceuticals. A series of major steps are involved in the production of peptides from microalgae, which include the disruption of the microalgal cell wall, the hydrolysis of proteins, and the extraction or isolation of peptides derived from hydrolysis. Physical methods of cell wall disruptions are favored due to the ability to obtain high-quality protein fractions for peptide production. Bioactive peptides are protein fragments of two to twenty amino acid residues that have a beneficial impact on the physiological functions or conditions of human health. Strong scientific evidence exists for the in vitro antioxidant, antihypertensive, and anti-atherosclerotic properties of microalgal peptides. This review is aimed at summarizing the methods of producing microalgal peptides, and their role and mechanisms in improving cardiovascular health. The review reveals that the validation of the physiological benefits of the microalgal peptides in relation to cardiovascular disease, using human clinical trials, is required. Full article

The inadequate disposal of tires poses a significant threat to human health and requires effective recycling solutions. The crosslinked structure of rubber, formed through sulfur bridges during vulcanization, presents a major challenge for recycling because it prevents the rubber scraps from being reshaped thermoplastically. Reclaiming or devulcanization aims to reverse this crosslinking, allowing waste rubber to be transformed into products that can be reprocessed and revulcanized, thereby saving costs and preserving resources. Microwave technology shows promise for devulcanization due to its ability to break sulfur crosslinks. In this study, we investigate the devulcanization of ground tire rubber (GTR) through a combined process applied to samples from both car and truck tires subjected to varying periods of microwave irradiation (0, 3, 5 and 10 min). The devulcanized GTR was then blended with natural rubber (NR) and underwent a new vulcanization process, simulating recycling for novel applications. The GTR was mixed with NR in proportions of 0, 10, 30 and 50 parts per hundred rubber (phr). This study also examines the differences between the GTR from car tires and GTR from truck tires. The results showed that the treatment effectively breaks the crosslinks in the GTR, creating double bonds (C=C) and improving the mechanical properties of the revulcanized samples. The crosslinking density and related properties of the samples increased with treatment time, reaching a maximum at 5 min of microwave treatment, followed by a decrease at 10 min. Additionally, the incorporation of GTR enhanced the thermal stability of the resulting materials. Full article

Guanine-rich sequences of nucleic acids, including DNA and RNA, are known to fold into non-canonical structures named G-quadruplexes (G4s). Such arrangements of these macromolecular polymers are mainly located in telomeres and in promoter regions of oncogenes and, for this reason, they represent a potential target for compounds with therapeutic applications. In fact, the ligand-mediated stabilization of G4s inhibits telomerase and the activity of transcriptional machinery and counteracts cancer cell immortalization. Flavonoids, along with other classes of small molecules, have been previously tested for their ability to stabilize G4s, but the mechanism of their interaction has not been fully elucidated. In the current work, we report a multi-technique investigation on the binding of tosylated isoflavones obtained by the B-ring modification of compounds from Maclura pomifera to a telomeric DNA sequence. Our study demonstrates that such derivatization leads to compounds showing lower binding affinity but with an increased selectivity toward G4 with respect to double-stranded DNA. The binding mode to the macromolecular target G4 was studied by combining results from electrospray mass spectrometry binding studies, nuclear magnetic resonance experiments and computational simulations. Overall, our findings show that tosylation influences the selectivity toward the macromolecular target by affecting the interaction mode with the nucleic acid. Full article

We attempted to perform surface microfabrication of the bioabsorbable material lactic acid–glycolic acid copolymer (LG-80) using a micro-imprint lithography technique with a gas-permeable porous mold at less than 5 °C. As a result, high-resolution surface micromachining with a height of 1.26 μm and a pitch of 2.97 μm was achieved using a convex sapphire mold with a height of 1.3 μm and a pitch of 3 μm. After processing, the LG-80 exhibited high water repellency, and FT-IR analysis of the surface showed no significant change in its chemical structure, confirming that the surface microfabrication was successful, while retaining the properties of the material. This demonstrated new possibilities for surface microfabrication technology for bioabsorbable materials, which are expected to be applied in the medical and life science fields in products such as surgical implants, tissue regeneration materials, and cell culture scaffold materials. In particular, the use of micro-imprint lithography enables low-cost and high-precision processing, which will be a major step toward the practical application of bioabsorbable materials. Full article