Volume 20 Issue 4

Eucalyptus hybrids exhibit rapid growth, and their wood is widely used in construction, furniture production, reconstituted panels, energy, pulp, and paper manufacturing. However, they are commonly affected by decay fungi, which reduce their durability, jeopardizing the integrity of structures and the safety of individuals. Therefore, this study aimed to evaluate the effects of thermal treatment on the biological resistance of 14-year-old hybrid Eucalyptus clone wood. Chemical analyses were conducted on the wood (lignin and holocellulose), and tests with brown rot fungi (Gloeophyllum trabeum and Rhodonia placenta) and white rot fungi (Irpex lacteus) were performed over 12 weeks, along with colorimetric variable assessments. It was concluded that brown rot fungi caused more severe damage to the wood, also influencing its coloration. Under the conditions studied, a temperature of 200 °C promoted wood deterioration of the clones by xylophagous fungi. Regarding resistance classes, the clones were classified as highly resistant (A, C, and E) to the fungus I. lacteus, regardless of heat treatment. For the fungi G. trabeum and R. placenta, the clones detected as highly resistant (A and C) were those exposed to a temperature of 185 °C.

Spoiled tomato fruits exhibited fungal infections, and the isolates were identified as Penicillium expansum, Alternaria alternata, Aspergillus terreus, and Fusarium oxysporum. Varying doses of chitinase, β-1,3-glucanase, and a chemical fungicide were tested against four fungal pathogens. All treatments showed dose-dependent inhibition of fungal growth. The chemical fungicide caused complete inhibition at the highest dose, while chitinase and β-1,3-glucanase significantly reduced colony size, especially in P. expansum and A. alternata, though they were less effective against A. terreus and F. oxysporum. This study rigorously investigated the molecular docking interactions of chitinase (PDB ID: 1CTN) and β-1,3-glucanase (PDB ID: 4M80), with target proteins of F. oxysporum (PDB ID: 7T69). Molecular simulations revealed compelling binding affinities, with chitinase demonstrating a docking score of -82.67 kcal/mol and β-1,3-glucanase exhibiting a score of -78.1 kcal/mol. Detailed interaction analyses revealed distinct binding mechanisms: Chitinase forms a stable complex through multiple hydrogen bonds and significant π-π stacking with key residues such as TRP210, while β-1,3-glucanase employs extensive hydrogen bonding and strong ionic interactions, notably with GLU121, for electrostatic stabilization. These findings provide critical molecular insights into the antifungal capabilities of these enzymes, highlighting their potential as agents to combat postharvest fungal pathogens.

For contemporary users’ emotional demands and the promotion of Ming-style furniture, which has cultural value, this paper studies the Ming-style ‘Warped Table’. A systematic re-design process is provided, consisting of Kinaesthetic Engineering (KE), Semantic Differential (SD), Factor analysis, Likert-weighted scoring, and Quality Function Deployment (QFD). Affective assessment was carried out by using SD questionnaires and text mining. Perceptual factor analysis yielded four major dimensions of perception, including ‘Material Warmth’ (29.9%), ‘Functional Serenity’ (25.4%), ‘Resilient Grace’ (22.9%), and ‘Fluid Elegance’ (21.9%). Relative importance was computed by the Likert Weighting method. Afterwards, a ‘sensory demand-design element’ mapping model was created with QFD, in which 7.9% were table-top and 7.2% legs as significant design elements. Modular redesign has been carried out, maintaining the traditional stylistic language “simple, elegant, and graceful” together with the mortise-and-tenon craft, but with new manufacturing logic and user sensory desires. The methodology realizes quantitative analysis and parametric translation of traditional furniture imagery, greatly improving the product’s cultural and emotional display, and gives a series of system references for related design work.

Mechanical and physical characteristics were studied of epoxy composites reinforced with different blends of the Hibiscus (H) rosa plant fiber and snake (S) grass fiber, with and without the addition of neem gum powder. The incorporation of the snake grass fiber significantly enhanced the mechanical properties, with the biocomposite 20S10H exhibiting the highest tensile strength (56 MPa), flexural strength (87 MPa), hardness (86 SD), and impact strength (6.98 J), due to the synergistic effect of snake grass fiber and neem gum as a binder. The interlaminar shear strength also showed an improvement, reaching a maximum of 6.52 MPa for the biocomposite 20S10H, reflecting enhanced interfacial bonding and reduced void content. Water absorption (40%) decreased with the increased proportion of snake grass fiber and the inclusion of neem gum, with the lowest absorption recorded for the biocomposite 30S30H, indicating reduced moisture uptake. In contrast, biocomposites with a higher proportion of Hibiscus rosa fiber exhibited higher water absorption. The scanning electron microscopy (SEM) study of the fracture surfaces demonstrated enhanced fiber-matrix adhesion and decreased porosity in biocomposites with neem gum, validating the neem gum’s contribution to better interfacial bonding and overall biocomposite efficacy.

A comprehensive understanding of the influences of joining parameters and material-related factors on the ultrasonic joining process for fiber-based materials is essential to optimize the process parameters in a targeted manner. Previous studies have been limited to commercially available materials with unknown compositions, leaving fundamental influencing factors largely unexplored. In this study, paper made from cellulose-rich natural fibers was used to systematically analyze the effects of amplitude, joining force, moistening, and joining energy. Effects of fiber type and fiber length were systematically analyzed. The joining force had the greatest influence on the joint strength across all materials analyzed, followed by humidification and joining energy. In contrast, amplitude only had a minor influence on the joint strength. The fiber type and fiber length also had a significant influence on the strength of the joint, with joints made from softwood fibers tending to have higher strength values. In addition, the bleaching process improves the joint strength because of the lignin reduction, as it promotes fiber cross-linking. Mechanically digested fibers (CTMP), on the other hand, proved to be less suitable for the ultrasonic joining process, as their increased stiffness made it more difficult to form a stable joint, compared to fibers obtained by purely chemical delignification.

Freshwater weeds (Eichhornia crassipes, Lemna minor, Azolla pinnata, Myriophyllum indicum and Nymphoides peltatum) were used as fermentation substrates to increase production of peroxidase enzyme. The pretreated freshwater weeds released sugars which favoured bacterial growth and peroxidase yields. The cellulose content of macroalgae ranged from 15.9±0.42 to 26.4±0.18% and the maximum amount was detected in L. minor (26.4±0.18%). Lignin content was high (8.3±0.4%) in A. pinnata and hemicellulose content was highest (26.5±0.92%) in E. crassipes. Peroxidase production was high in the L. minor biomass (7.28 ±0.41 U/g), followed by E. crassipes (6.72±0.3 U/g). The isolated bacteria C18 produced dye degrading-enzymes such as tyrosinase (2.74±0.3 U/mL), lignin peroxidase (0.71±0.02 U/mL), NADH-DCIP reductase (1.49±0.03 U/mL), laccase (29.8±1.1 U/mL), and azoreductases (35.4±0.15 U/mL). Central composite design and response surface methodology were used to improve peroxidase production by Bacillus flexus. Peroxidase production improved with an increase in initial pH value, low levels of glucose, and ammonium sulphate. B. flexus decolourized methyl red (>75%) and Congo red (>60%) in the culture medium. Lemna minor is a cost-effective culture medium for peroxidase production. The enzyme-based bioremediation reduces toxic pollutants in water systems, thereby potentially reducing health risks due to environmental exposure.

Despite their dubious safety, nanoparticles (NPs) are beneficial in many areas, particularly in agriculture. Though a variety of commercial nano- fertilizers, pesticides, and insecticides are available, little is known about their potential detrimental effects on plant cells. A Se/ZnO nanoparticle complex was synthesized utilizing Ficus nitida fruit extract as both a reducing and stabilizing agent, yielding an eco-friendly product.The common food plant Allium cepa was treated with Se/ZnO NP suspension. Transmission electron microscopic analyses of the NPs were performed, including  Dynamic Light Scattering (DLS), zeta potential, X-ray diffraction, and FTIR characterizations.This study examined the cytological impact and chromosomal patterns of Allium cepa root meristems after treatment by Se/ZnO-NPs. Results show that all applied concentrations of NPs decreased the mitotic index (MI). The many chromosomal defects that were caused by NPs included disrupted and sticky chromosomes. Aflatoxin levels (B1, B2, G1, G2) were quantified in vegetables inoculated with Aspergillus flavus. Tomatoes and potatoes showed the highest contamination, in contrast, garlic and beet exhibited minimal or undetectable levels, suggesting resistance. The effect of Se/ZnO-NPs (0 to 40 ppm) on A. flavus growth and aflatoxin production was evaluated. While 5 ppm stimulated growth, higher concentrations significantly reduced both biomass and aflatoxins. These findings suggest that Se/ZnO- NPs treatment as an effective strategy to suppress A. flavus and its toxin production in contaminated crops.

This study focuses on the development and characterization of lightweight hybrid epoxy composites reinforced with neem gum (NG) and coconut dust (CD), targeting sustainable structural applications. Composites were fabricated with a constant 70% epoxy resin and varying NG and CD contents (5NG25CD, 10NG20CD, 15NG15CD, 20NG10CD, and 25NG5CD). Among these, the 15NG15CD composition demonstrated optimal performance, achieving a tensile strength of 42.1 MPa, flexural strength of 83.2 MPa, impact strength of 6.12 J, and Shore D hardness of 82. Water absorption tests showed significantly reduced moisture uptake (25.6%), indicating enhanced dimensional stability. Sound absorption tests revealed a peak sound absorption coefficient of 0.35 for the 20NG10CD composite, followed by 0.33 for 15NG15CD, indicating effective acoustic damping characteristics across all variants (ranging from 0.24 to 0.35). Scanning electron microscopy (SEM) revealed strong interfacial adhesion and uniform particle dispersion within the epoxy matrix, contributing to superior mechanical properties. These eco-friendly, lightweight composites exhibited excellent strength, moisture resistance, and versatility, making them suitable for lightweight structural components, automotive interiors, and sustainable packaging solutions.

Mycelium-based biocomposites (MBC) offer a sustainable alternative to synthetic materials due to their biodegradability and low environmental impact. This study examined the structural and mechanical properties of mycelium films produced from nine fungal species representing monomitic, dimitic, and trimitic hyphal systems. These species were selected following preliminary screening of 21 strains for growth characteristics and mechanical performance. Growth rates varied significantly, with Irpex lacteus exhibiting the fastest growth (8 mm/day), while Fomes fomentarius and Daedaleopsis confragosa grew more slowly but exhibited superior mechanical strength. Tensile testing identified D. confragosa as the strongest fungus (6.51 MPa), followed by F. fomentarius, although considerable variability was noted. Ganoderma spp. and Trametes spp. showed moderate to low tensile strength. No consistent correlation was found between mycelium density and tensile strength, nor did chitin content alone explain mechanical performance. For instance, I. lacteus had the highest chitin content but weak tensile properties. Scanning electron microscopy revealed differences in hyphal diameter, density, and cell wall structure, indicating that factors such as glucan-chitin interactions and hyphal morphology influence mechanical behavior. These findings highlight the potential of less investigated fungal species in advancing MBC development.

Tetra Pak (TP)/bamboo fiber (BF) composites were prepared using waste TP and bamboo fiber as the main raw materials. Twelve inorganic flame retardant systems were used to modify the flame retardancy of TP/BF composites. Specimens were evaluated with the limiting oxygen index test, water absorption test, dry shrinkage and wet expansion test, mechanical property test, and Fourier transform infrared spectroscopy (FTIR). The results showed that the composite flame retardant systems outperformed the single flame retardant system, with the limiting oxygen index reaching up to 37.6%. Retardant addition lowered the modulus of elasticity (MOE), modulus or rupture (MOR), and internal bond (IB) and impaired dimensional stability, the extent varying with type and dosage.  Among them, the TP/BF composites modified by systems Z3, Z8, Z9, and Z12 satisfied GB/T 11718-2021requirements for ordinary, furniture, and building medium-density fiberboards. FTIR showed the presence of chemical bonds of various functional groups that would be consistent with the development of adhesion within the composite.