University of Forestry

Wood decomposition by fungal communities plays a crucial role in regulating carbon dynamics and biodiversity within coarse woody debris (CWD), and these processes may be influenced by environmental change. However, the geographical distribution and functional roles of wood-decaying fungi are poorly explored. In the present study, we focused on CWD of Norway spruce, a dominant conifer species widely distributed in western Eurasia. Chemical analyses of 374 wood samples from six forest sites in central and southeastern Europe revealed a positive association between mean annual temperature (MAT) and dilute alkali solubility, a proxy for brown rot. DNA metabarcoding revealed associations between climatic conditions and wood-decaying fungal communities. Remarkably, the occurrence frequency of the dominant brown rot fungus, Fomitopsis pinicola, was positively correlated with MAT. These findings suggest that higher temperatures may promote lignin accumulation in Norway spruce CWD across central to southeastern Europe, potentially contributing to carbon storage in forests.

Quantitative data on the bending capacity and rotational stiffness of corner joints made from acrylic solid-surface PMMA/ATH composites are limited, despite their widespread use in furniture and interior components. The study provides comparative bending moment and rotational-stiffness benchmarks for 18 PMMA/ATH corner-joint series, using a stiffness-evaluation procedure tailored to corner-joint testing. L-type joints produced from two commercial PMMA/ATH materials (Kerrock and Corian) at 6- and 12-mm thickness were manufactured in 18 configurations, including glued butt, 45 degrees mitre, reinforced mitre, rebate, groove variants, and detachable Minifix eccentric and Lamello Clamex connectors. Specimens were tested under arm-compression bending and maximum bending moment (Mmax), and joint rotational stiffness was derived. The best-glued solution was the 12 mm Kerrock 45 degrees mitre with Mmax 186.21 N & centerdot;m, whereas the strongest 6 mm joint reached 40 N & centerdot;m. Reinforcing the 12 mm Kerrock mitre joint increased stiffness to 9521 N & centerdot;m/rad but did not increase bending capacity relative to the non-reinforced mitre. Detachable joints formed a clearly distinct low-rigidity class with bending moments of 2.22-3.89 N & centerdot;m and stiffness below 194 N & centerdot;m/rad. Overall, thickness and joint geometry dominate both strength and stiffness, and the tested detachable connectors should be reserved for applications requiring disassembly rather than for load-bearing corners.

Banana pseudostem (Musa sp.) fibers from 10 Indonesian cultivars were evaluated as candidate renewable sources for biomaterial development. Their physical properties (density and moisture content), mechanical strength (tensile strength and elastic modulus), and chemical composition, including lignin, holocellulose, α-cellulose, and hemicellulose content levels were analyzed. Pyrolysis–gas chromatography-mass spectrometry (Py-GC/MS) was employed to determine the syringyl-to-guaiacyl (S/G) ratio, providing insights into the lignin structure. Among the samples, D20 (Cavendish) showed consistent performance characterized by its high holocellulose content (52.2%), substantial α-cellulose fraction (33.3%), and superior mechanical strength, with a tensile strength of 166 MPa and an elastic modulus of 4480 MPa. Accordingly, this cultivar was selected for further investigation. Fourier transform infrared (FTIR) spectroscopy confirmed the presence of functional groups characteristic of lignocellulosic biomass, including hydroxyl, carbonyl, aromatic, and glycosidic linkages. X-ray diffraction (XRD) analysis revealed semicrystalline cellulose, while scanning electron microscopy (SEM) indicated a compact fiber structure with a defined lumen and minimal surface degradation. These findings suggest that fibers from D20 exhibit a promising balance of chemical, structural, and morphological characteristics, supporting their suitability for bio-based composite applications. Overall, this research emphasizes the underutilized potency of local banana waste as a foundation for sustainable material innovation.

Ferulic acid (FA) is a phenolic compound derived from biomass and agro-industrial residues that exhibits significant antimicrobial bioactivity. It inhibited the proliferation of foodborne bacteria and fungi and biofilm formation, which are precursors to food contamination. However, its efficacy is often limited by intrinsic constraints, such as low thermodynamic stability, poor aqueous solubility, and susceptibility to degradation. To overcome these limitations, various technical interventions have been developed to strengthen its molecular interactions and stability. This article reviews the antimicrobial mechanism of FA and strategies to enhance its efficacy through structural and technical interventions. The key findings indicate that structural modifications and conjugation are carried out through the synthesis of chemical derivatives, grafting onto antimicrobial polymers, and combining with other phenolic compounds to increase affinity for microbial cell membranes—emulsion formation with essential oils and photo-inactivation to enhance cellular penetration. Combinations with antibiotics or specific antimicrobial agents aim to lower the minimum inhibitory concentration (MIC) while mitigating the risk of microbial resistance. Although challenges in oxidation and sensory alterations (changes in taste/aroma) remain, it is concluded that the strategy to enhance the FA antimicrobial activity transforms it from a sensitive natural extract into a robust, multifunctional agent used as a functional additive, bioactive agent in packaging material, stabilizer/emulsifier, and crosslinker. This evolution is crucial for developing sustainable food preservation systems that effectively replace synthetic chemical preservatives by transforming biomass/agroindustrial residue.

Fractional calculus, the study of derivatives and integrals of arbitrary order [...]