Lavender is a valued plant due to its cosmetic, perfumery, culinary, and health benefits. A wide range of applications is related to the composition of bioactive compounds, the quantity and quality of which is determined by various internal and external factors, i.e., variety, morphological part of the plant, and climatic and soil conditions during vegetation. In the presented work, the characterization of antimicrobial properties as well as the qualitative and quantitative assessment of bioactive compounds in the form of polyphenols in ethanol extracts from leaves and flowers of Lavandula angustifolia Mill. intended for border hedges, cultivated in the region of southern Poland, were determined. The composition of the fraction of volatile substances and antioxidant properties were also assessed. The conducted research shows that extracts from leaves and flowers significantly affected the viability of bacterial cells and the development of mold fungi. A clear decrease in the viability of bacteria and C. albicans cells was shown in the concentration of 0.32% of extracts. Leaf extracts were characterized by a much higher content of polyphenols and antioxidant properties than flower extracts. The composition of volatiles measured by GC-MS was significantly different between the extracts. Linalyl acetate and ocimene isomers mix dominated in flower extracts, whereas coumarin, γ-cadinene, and 7-methoxycoumarin were identified as dominant in leaf extracts.

The purpose of this study was to characterize ethanol extracts from leaves and flowers of two ecotypes (PL—intended for industrial plantations and KC—intended for cut flowers) of Lavandula angustifolia Mill. The plant was cultivated in 2019 in southern Poland as part of a long-term research plan to develop new varieties resistant to difficult environmental conditions. The collected leaves and flowers were used to prepare ethanol extracts, which were then analyzed in terms of phytochemical composition and antioxidant, bactericidal, and fungicidal properties. Using UPLC techniques, 22 compounds belonging to phenolic acids and flavonoids were identified. UPLC test results indicated that ethanol extracts from leaves and flowers differ in phytochemical composition. Lower amounts of phenolic acids and flavonoids were identified in leaf extracts than in flower extracts. The predominant substances in the flower extracts were rosmarinic acid (829.68–1229.33 µg/g), ferulic acid glucoside III (810.97–980.55 µg/g), and ferulic acid glucoside II (789.30–885.06 µg/g). Ferulic acid glucoside II (3981.95–6561.19 µg/g), ferulic acid glucoside I (2349.46–5503.81 µg/g), and ferulic acid glucoside III (1303.84–2774.17 µg/g) contained the highest amounts in the ethanol extracts of the leaves. The following substances were present in the extracts in trace amounts or at low levels: apigenin, kaempferol, and caftaric acid. Leaf extracts of the PL ecotype quantitatively (µg/g) contained more phytochemicals than leaf extracts of the KC ecotype. The results obtained in this study indicate that antioxidant activity depends on the ecotype. Extracts from the PL ecotype have a better ability to eliminate free radicals than extracts from the KC ecotype. At the same time, it was found that the antioxidant activity (total phenolic content, ABTS^•+, DPPH^•, and FRAP) of PL ecotype leaf extracts was higher (24.49, 177.75, 164.88, and 89.10 μmol (TE)/g) than that determined in flower extracts (15.84, 125.05, 82.35, and 54.64 μmol (TE)/g). The test results confirmed that leaf and flower extracts, even at low concentrations (0.313–0.63%), significantly inhibit the growth of selected Gram-negative and Gram-positive bacteria and Candida yeasts. Inhibition of mold growth was observed at a dose extract of at least 1 mL/100 mL.

Results of research on the diversity of wood-rot fungi found in buildings and outdoor wooden engineering structures in Poland are presented in this article. A total of 47 species and genera of wood-rot fungi from Basidiomycota (19 brown rot fungi, 28 white rot fungi) and 1 genus from Ascomycota (1 fungus that does not cause wood decay) were found in damaged buildings. The greatest number of wood-rot fungi was reported on outdoor wooden engineering structures (33 species), followed by unoccupied residential buildings (30 species). The lowest diversity was found in occupied residential buildings (20 species). A total of 34 species and genera of fungi were found in all examined structures, out of which 17 species caused brown rot, 16 caused white rot, and 1 did not cause wood decay.

This work carried out research to determine the possibilities of using graphene oxide to provide wood with new functional features. With the saturation parameters used and working liquid with a concentration of 0.004% graphene oxide, the retention of the nanomaterial in wood was 0.25 kg/m³. The presence of graphene oxide increased the crystallinity of the wood to 64% (compared with 57% for unmodified wood). The TG/DTG spectra of wood impregnated with graphene oxide and the control wood indicated that the initial weight loss of the samples observed at a temperature of 100 °C was similar and amounted to less than 4%. A second mass loss was observed in a temperature range of 270 to 380 °C. The mass loss in this temperature range reached 70% and was similar in the test and control samples. Wood modified with graphene oxide showed increased thermal stability in a temperature range of 360 to 660 °C compared with native wood. Given the results obtained, there were no statistically significant differences in the water absorption of modified or control wood. The presence of low concentrations of graphene oxide in the culture medium did not inhibit the growth of the fungus Trichoderma viride; however, a decrease in the growth activity of mycelial hyphae was observed with an increasing concentration of nanomaterial in the medium. It has been reported that graphene oxide, as a stress factor, initiates changes at the cellular level, characterized by the formation of structures called chlamydospores by the body.

The paper presents the preliminary results of cellulose modification by ion implantation. Three types of ions were implanted, i.e., copper, zinc and silver with fluences of 5 × 10¹⁴ and 5 × 10¹⁵ cm⁻², respectively. The acceleration voltage of the implanted ions was 30 kV. The ion penetration depth profiles showed differences, especially in the Cu and Ag cases, due to the different ion beams of these elements. The implantation of cellulose with ions clearly changed the wettability of the material surface in the direction of hydrophobicity. The impact of implantation on the growth of the cellulose surface by mold fungi was also noticeable. Only the silver ion implantation had a negative effect on the growth of the Trichoderma viride fungus but did not cause a complete inhibition of growth. Cellulose implantation with Cu and Zn ions clearly stimulated the growth of fungi on the surface of the polymer.

The production of environmentally friendly biocomposites can be based on attractive and low-cost vegetable pomace, a waste product from oil production. In the present study, biocomposites made from HDPE and pomace from black cumin, corn, and flax seeds were subjected to evaluation of structural, morphological, and thermal parameters and susceptibility to germination by filamentous fungi. Based on the characteristics of the produced biocomposites, it should be concluded that vegetable waste from oil production, applied at a 1:1 ratio as a filler for polyethylene-based biocomposites, significantly reduces the crystallinity of the produced material and decreases its thermal stability. It should also be noted that such biocomposites are more easily overgrown by fungi, which may facilitate their biodegradation. Very poor antioxidant properties, resulting from the encapsulation of the plant fraction in polyethylene, limit the functionality of this type of material as, for example, active biomaterials to prevent free radical processes. Although the structural and physical characteristics of the produced biocomposites have been shown to be inferior to polyethylene, efforts should be made to improve these characteristics. Plant waste can be a valuable raw material for the production of materials compatible with various industries.