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This study investigates how biogenic mesoporous silica nanoparticles (MS-NPs) extracted from rice straw residues, a sustainable and economical bio-source, affect White Ordinary Portland Cement (WOPC) paste performance. A comprehensive investigation using varied fractions of 0.25, 0.50, 0.75, and 1.0% MS-NPs as an additive to WOPC was conducted to analyze the physicomechanical characteristics of WOPC-MS hardened composites, including compressive strength, fire resistance, and water demand. The beneficial impact of biogenic MS-NPS was verified by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and differential thermo-gravimetric analysis (TGA/DTG) methods, revealing several hydration products such as calcium silicate hydrates (CSHs), calcium ferrosilicate hydrates (CFSHs), and calcium aluminosilicate hydrates (CASHs). These products enhance the overall physical and mechanical properties and the thermal stability of hardened WOPC-MS. The composite comprising WOPC-0.75 MS provides numerous advantages from both an economic and environmental perspective., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

In this study, we explore the structural intricacies of cellulose, a polymer composed of glucose monomers arranged in a linear chain, primarily investigated through solid-state NMR techniques. Specifically, we employ low-field proton nuclear magnetic resonance (H-NMR) to delve into the diverse hydrogen atom types within the cellulose molecule. The low-field H-NMR technique allows us to discern these hydrogen atoms based on their distinct chemical shifts, providing valuable insights into the various functional groups present in cellulose. Our focus extends to the examination of anomeric protons of glucose units and protons linked to carbon atoms engaged in glycosidic linkages within cellulose chains, which exist in diverse crystalline and amorphous forms. Solid-state low-field H-NMR spectroscopy aids in characterizing the crystallinity degrees and amorphous regions within cellulose, revealing time-dependent changes in free induction decay (FID) signals. Complementing this, we investigate the photo-absorption properties of cellulose fibers under both continuous and modulated irradiation using reversed double-beam photoacoustic spectroscopy (RDB-PAS). This photoacoustic approach allows us to observe ultraviolet- and visible light-induced processes, including electron trap filling and reductive changes on the fiber surface. Our findings suggest that RDB-PAS is a feasible method for estimating the electron trap distribution, serving as a potential measure of the density of crystalline cellulose defects. This integrated approach of combining solid-state low-field H-NMR and RDB-PAS techniques offers a comprehensive understanding of cellulose structure and properties, enhancing our ability to characterize its diverse features., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Food commodities, including mycotoxins naturally produced from toxigenic fungi (pre- or post-harvest), are particularly vulnerable to contamination. The study intended to use unique bioactive composites loaded with antimicrobial constituents for food packaging. Three composite types are based on carboxymethyl cellulose/shellac (CMC/SH) and loaded with pomegranate extract (POE) with or without jojoba oil (JOE) at various concentrations. An enhancement was recorded for tensile strength and elongation at break and burst properties of the composites, where the results point out the amelioration of flexibility and elasticity with E9 (0.3/3 mg/mL of POE/JO). Moreover, E10 (0.3/1 of POE/JOE) content had higher phenolic and flavonoids, with significant antioxidants and the best antimicrobial and anti-mycotoxigenic activity. Six higher antimicrobial composites were chosen for corn seed coating applications in a simulated experiment of toxigenic fungal contamination, where the results recommend E10 as the best formula for packaging application. The E10 was characterized for emulsion stability, particle size, zeta potential, pH, PDI, and acidity that were recorded at 88.16 ± 2.87%, 54.81 nm, 38.74 mV, 6.34 ± 0.54, 31.12 ± 1.02, and 6.02 ± 0.34 mg/L, respectively. The in-silico study revealed that ellagic acid and hesperidin in POE extract, erucic and oleic acids in JOE, and shellac had the highest binding free energies against the vital enzymes involved in bactericidal/bacteriostatic effects and the aflatoxin bio synthetic mechanism., Competing Interests: Declarations. Competing interest: The authors declare no competing interests., (© 2024. The Author(s).)

A new method was developed to quickly produce carboxymethyl hemicellulose (CM-Hemi) and fluorescent nitrogen-doped carbon dots (N-CDs) from sugarcane bagasse (SB). These materials were then combined with calcium chloride (CaCl₂) to create hydrogel sensors with antibacterial and antifungal properties. The CM-Hemi@Ca-N-CDs hydrogel was effective against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria compared to CM-Hemi@Ca which give no antibacterial activity. Both hydrogels also exhibited antifungal properties against Candida albicans. Molecular docking studies revealed that the CM-Hemi@Ca-N-CDs hydrogel had strong binding interactions with the protein from Staphylococcus aureus and Candida albicans (1.92 A°) compard to Escherichia coli (2.01 A°), which was aligned with the inhibition zone measurements from the antibacterial test. The fluorescence microscope revealed differences in the emitted light color when the hydrogel interacted with different types of microorganisms, likely due to variations in their cell walls. Density functional theory (DFT) calculations indicate that the incorporation of N-CDs into the CM-Hemi@Ca hydrogel enhances its stability and rigidity. This is evidenced by the lower energy gap (E g ), higher electron affinity (μ), and lower softness (S) of the CM-Hemi@Ca-N-CDs compared to the CM-Hemi@Ca hydrogel. Additionally, the formation of amide bonds between the N-CDs and CM-Hemi contributes to the increased rigidity of the hydrogel.These findings supporting th effectiveness of CM-Hemi@Ca-N-CDs as an antibacterial/antifungal sensor., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Compounds containing the piperidine group are highly attractive as building blocks for designing new drugs. Functionalized piperidines are of significant interest due to their prevalence in the pharmaceutical field. Herein, 3-oxo-3-(piperidin-1-yl) propanenitrile has been synthesized, and piperidine-based sodium alginate/poly(vinyl alcohol) films have been prepared. The polymeric films display potency and potential for application to fight against microbial infections. The films could also help maintain interaction with tissue to ensure the controlled release of therapeutic molecules. Thus, they are promising in developing drug delivery systems essential in the pharmaceutical industry. The structure of the 3-oxo-3-(piperidin-1-yl)propanenitrile was confirmed via spectroscopic and single crystal x-ray diffraction techniques. A homogenous solution of sodium alginate (SA) was used to prepare the film by the casting method in the presence of poly(vinyl alcohol) (PVA) and 3-oxo-3-(piperidin-1-yl)propanenitrile (PPN). The prepared films were characterized physiochemically via FTIR, XRD, and TGA. The film morphology was studied using SEM. The antimicrobial potency of the prepared films was assessed against various species of microorganisms. The physicochemical analysis indicated that the films were bound by chemical and physical bond formation between the cyano group of 3-oxo-3-(piperidin-1-yl)propanenitrile, methylene group of PVA, and the hydroxyl group of SA. The films showed smooth, homogenous surfaces and good mechanical properties. The results revealed that the films are bioactive, as indicated by promising antimicrobial potency against P. aeruginosa, S. aureus, E. coli, B. subtilis, and C. albicans, with high potency as well as moderate activity against A. niger. Polymeric films have promising potential to be utilized in drug delivery applications., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)