Search Results (19)

Stinging nettle (Urtica dioica L.) is a multipurpose perennial plant with growing interest as a source of nutrients for both human and animal consumption. Despite its recognized nutritional potential, limited research has addressed how agronomic practices influence its nutritional quality. The aim of the present study was to assess the effects of plant density and fertilization on the micro- and macronutrient content of nettle plants and seeds. A three-year field experiment (2021–2024) was conducted under Mediterranean conditions using a split-plot design with two plant densities (12 and 16 plants m⁻²) and three nitrogen fertilization regimes [control (0 kg N ha⁻¹), urea (200 kg N ha⁻¹), and urea with urease inhibitor (200 kg N ha⁻¹)]. Results showed that nitrogen fertilization significantly affected macronutrient composition, increasing crude protein and crude carbohydrates (by up to 6% and 4% respectively) while reducing crude fat and fiber contents by up to 10% in nettle plants. However, fertilization negatively influenced the concentrations of Mg, Zn, K, and Mn in seeds and reduced their content by up to 16%, 4%, 9%, and 5% respectively. On the contrary, Fe and Cr increased under nitrogen application. Plant density had a minor effect on nutritional content, mainly improving protein accumulation in lower densities. Overall, U. dioica demonstrated a stable nutritional profile and high mineral content, therefore supporting its potential as a sustainable dual-purpose crop for food and feed systems. The findings of the present study indicate that proper crop management can significantly improve the nutrient content of nettle plants and seeds. Full article

Continuous nettle fiber-reinforced PLA composites were fabricated using a custom-designed fused deposition modeling (FDM) 3D printer equipped with an in-nozzle fiber impregnation system. The influence of hatch spacing and layer thickness on fiber volume fraction, tensile strength, and fracture surface morphology was systematically examined. Fiber content increased from 7.94 vol.% to 12.21 vol.% when hatch spacing was reduced from 1.0 mm to 0.6 mm at a constant 0.4 mm layer thickness, and from 12.21 vol.% to 24.43 vol.% when layer thickness was decreased from 0.4 mm to 0.2 mm at a fixed 0.6 mm hatch spacing. When compared to neat PLA, tensile strength was improved by 18.69% for the configuration of 1_04 and 75.83% for the configuration of 06_02. SEM analysis revealed orderly fiber deposition in all samples, with 3D-printing-induced voids and fiber pull-out observed on fracture surfaces. Reduced hatch spacing and layer thickness resulted in denser fiber packing, consistent with mechanical performance trends. The results highlight the strong influence of printing parameters on the microstructural and mechanical behavior of continuous natural fiber composites produced by FDM. Full article

Kefir is a historic dairy-fermented beverage produced using lactic acid bacteria and yeast as a starter culture and is considered nutritious with a good taste. Many studies have been conducted to incorporate various possible functional materials into kefir to enhance its nutritional value. This study aims to enrich kefir with 0.25% and 0.5% of Stinging nettle (Sn) powder before fermentation to improve its nutritional value. Stinging nettle (Urtica dioica) is a nutritious and multifunctional herb with a variety of healthful components such as fibers and polyphenols; it has significant potential as a useful food functional ingredient. The physicochemical, microbial, and nutritional properties of kefir fortified with Sn were examined weekly during refrigerated storage for 21 days. The results showed that adding Stinging nettle significantly (p < 0.05) increased the probiotic counts from 7.90 ± 0.22 log to 8.46 ± 0.19 log CFU/g, antioxidant activity (4%), and total polyphenol contents (5%) in kefir yogurt after 12 days of refrigerated storage. The addition of Sn also had a positive effect on the acidity of kefir and increased the viscosity and the syneresis to a certain extent. Furthermore, adding Sn increased lactic acid bacteria counts and the production of short-chain fatty acids after in vitro digestion and colonic fermentation. The results of this study indicated the potential use of Sn powder as a functional ingredient in kefir yogurt and other similar products. Full article

The utilization of nettle (Urtica cannabina) as feed is restricted by its material properties (antibacterial activity and high buffering capacity). This study hypothesized that the use of lactic acid bacteria (LAB) attached to nettles can improve these problems. Lactococcus garvieae (LG), Pediococcus pentosaceus (PP), and LG + PP (LP) isolated from nettles were inoculated into nettle silage to explore nutrient retention and the microbial community structure. The results showed that inoculation significantly delayed dry matter and crude protein loss, inhibited neutral detergent fiber and acid detergent fiber degradation, and reduced ammonia nitrogen (NH₃-N) accumulation. There was a significant increase in Firmicutes abundance after inoculation, and the dominant genus, Aerococcus, was negatively correlated with NH₃-N accumulation. In the later stages of the PP treatment, Atopistipes synergistically inhibited Clostridia with acetic acid. However, the high buffering capacity and antibacterial components of raw nettle led to increased pH values during the later fermentation stages, limiting sustained acid production by LAB. These results confirm that nettle-derived LAB can effectively improve the quality of silage by regulating the microbial community and the acidification process; however, they must be combined with pretreatment strategies or optimized composite microbial agents to overcome raw material limitations. This study provides a theoretical basis and technical support for the utilization of nettle as feed. Full article

Stinging nettles (Urtica dioica) have a long history of association with human civilization, having been used as a source of textile fibers, food and medicine. Here, we present a chromosome-level, phased genome assembly for a diploid female clone of Urtica dioica from Romania. Using a combination of PacBio HiFi, Oxford Nanopore, and Illumina sequencing, as well as Hi-C long-range interaction data (using a novel Hi-C protocol presented here), we assembled two haplotypes of 574.9 Mbp (contig N50 = 10.9 Mbp, scaffold N50 = 44.0 Mbp) and 521.2 Mbp (contig N50 = 13.5 Mbp, scaffold N50 = 48.0 Mbp), with assembly BUSCO scores of 92.6% and 92.2%. We annotated 20,333 and 20,140 genes for each haplotype, covering over 90% of the complete BUSCO genes and including two copies of a gene putatively encoding the neurotoxic peptide urthionin, which could contribute to nettle’s characteristic sting. Despite its relatively small size, the nettle genome displays very high levels of repetitiveness, with transposable elements comprising more than 60% of the genome, as well as considerable structural variation. This genome assembly represents an important resource for the nettle community and will enable the investigation of the genetic basis of the many interesting characteristics of this species. Full article

This paper provides an interdisciplinary overview of nettle bioactive compounds and processing, and ir also explores its role in the circular bioeconomy. Urtica dioica L. is sometimes referred to as a multipurpose herbaceous species that has been used historically in food, textiles, and medicine owing its rich profile of biological compounds. This study synthesizes the recent literature to examine nettle’s applications across various industries, from nutritional supplements to eco-friendly fiber materials. In addition, it highlights nettle’s potential in sustainable production chains, aligning with the EU’s bioeconomy directives. The methods involve a comprehensive literature review and data analysis, with a focus on bioactive compounds and eco-sustainable applications. The results of this review underscore the plant’s unique adaptability to low-input farming and its contributions to reducing resource dependency. The findings position nettle as a valuable resource for sustainable innovation, emphasizing its relevance within circular economic models. Full article

Marginal lands have been proposed to produce non-food crop biomass for energy or green materials. For this purpose, the selection, implementation, and growth optimization of plant species on such lands are key elements to investigate to achieve relevant plant yields. Stinging nettle (Urtica dioica) is a herbaceous perennial that grows spontaneously on contaminated lands and was described as suitable to produce fibers for material applications. Two mercury-contaminated soils from industrial wastelands with different properties (grassland soil and sediment landfill) were used in this study to assess the potential growth of stinging nettle in a greenhouse mesocosm experiment. Two organic amendments were studied for their impact on nettle growth. The solid digestate from organic food wastes significantly doubled plant biomass whereas the compost from green wastes had a lower impact. The highest doses of organic amendments significantly increased the number of fibers, which doubled following digestate application, while reducing leaf Hg concentration. Both amendments significantly improved soil respiration and enzymatic activities linked to the microbial biomass in the soil from the sediment landfill by the end of the experiment. In the context of a phytomanagement scenario, solid digestate would be a preferred amendment resource to improve nettle production on industrial wastelands. Full article

Noise pollution is often overlooked and invisible, but it significantly impacts the quality of human life. One of the most straightforward solutions to mitigate noise pollution is by using sound-absorbing materials. Recently, research trends to develop sound absorbing green materials, typically derived from agricultural by-products, have witnessed an uptick. This paper summarizes the sound-absorbing properties of various green materials found in the literature, including coconut fiber, kenaf fiber, rice bran, rice husk, rice straw, Hanji (a traditional Korean paper), tea-leaf fiber, mandarin peel, pineapple-leaf fiber, corn husk, peanut shell, sugar palm trunk, Yucca gloriosa fiber, fruit stones, wood barks, flax fiber, and nettle fiber. Natural fibers can be made by compressing the raw material or manufacturing them into fibrous materials or composites. The key variables that determine sound absorption performance are the thickness and density of the green material, as well as the presence of an air back cavity. Generally, thicker materials exhibit better sound absorption performance in the low- and mid-frequency range. Moreover, higher density is associated with better sound absorption performance at the same thickness. Additionally, increasing the distance between the sound-absorbing material and the air back cavity enhances sound absorption performance at low frequencies. Thus, these physical variables, rather than the specific materials used, primarily influence sound absorption capabilities. Therefore, various green materials, such as fibers, granules, and porous materials, can be effective sound absorbers if their thickness, density, and air back cavity are properly controlled. Full article

The global demand for packaging materials and energy is constantly increasing, requiring the exploration of new concepts. In this work, we presented a bioeconomic concept that uses steam explosion and phase separation to simultaneously generate fibers for the packaging industry and biogas substrate for the energy sector. The concept focused on fiber-rich residues and fiber-rich ecological energy crops from agriculture. Feasibility of the concept in the laboratory using feedstocks, including Sylvatic silphia silage, Nettle silage, Miscanthus, Apple pomace, Alfalfa stalks, and Flax shives was confirmed. Our results showed that we were able to separate up to 26.2% of the methane potential while always extracting a smaller percentage of up to 17.3% of organic dry matter (ODM). Specific methane yields of 297–486 L_CH4 kg_ODM⁻¹ in the liquid and 100–286 L_CH4 kg_ODM⁻¹ in the solid phase were obtained. The solid phases had high water absorption capacities of 216–504% due to the steam explosion, while the particle size was not significantly affected. The concept showed high potential, especially for undried feedstock. Full article

Natural fibers are increasingly being used to make nonwoven fabrics, substituting synthetic materials for environmental and economic reasons. In this study, a series of needle-punched nonwoven fabrics were made by extracting fibers from coffee husks and blending them with a proportion of spinning waste consisting of cotton fibers and another five different natural fibers. This work investigates the coefficient of sound absorption, thermal conductivity, areal density, thickness, and air permeability. Overall, the sound absorption properties of the produced nonwoven fabric depend on the blend proportion and the number of layers. The results from the fabric containing nettle and banana fibers demonstrate a much-improved sound absorption coefficient. These results have been compared with those of commercially available nonwoven fabrics that are manufactured from polyester and polyurethane foam. The thermal conductivities of the fabrics made with nettle and coir were the highest and lowest, respectively. This is because of the fiber linear density, but all in all, fibers extracted from coffee husks show significantly promising potential for scaling up to replace existing synthetic fibers. Full article

Within the framework of the environmental policies which tend toward new ecological materials, without the use of petroleum-based materials, the objective of this work is to develop a composite 100% natural associating fibers of European nettles (Urtica Dioica) and PLA (Poly-Lactic Acid). After having determined the properties of both components of the new composite, a methodology was implemented to maximize the PLA/nettle association. Then, tensile tests with standardized specimens were carried out to assess the mechanical characteristics of this new composite, which are ultimately very dependent on its manufacturing process. Experimental results demonstrated that the manufacturing process results in a material with enhanced overall mechanical properties, compared to those found in the literature (Young’s modulus: 5.41 ± 0.23 GPa vs. 1.2 to 4.37 ± 0.14 GPa). Our findings suggest widespread use of this PLA/nettle composite, although its properties clearly stem from the quality of the nettle fiber, which is itself highly dependent on variable parameters linked to the growing conditions of the plant. The possible applications of this eco-friendly material seem to be very wide, as long as they do not have to undergo too important structural loads, as for example the sector of interior furniture, packaging, or even interior elements in the automotive sector. Full article

Growing environmental concerns are becoming significant challenges for large-scale applications in the automotive industry. Replacing and hybridizing glass fibers with natural fibers for non-structural applications is one effective way to address this challenge, while retaining the useful properties of both. This paper investigates the mechanical and damping performance of four types of compression-molded materials: polyester matrix (reference), nettle (6% by weight), hybrid 1 (6% glass and 6% nettle by weight), and hybrid 2 (12% glass and 6% nettle by weight), with polyester matrix at an ambient temperature. The tensile tests using digital image correlation (DIC) showed that by adding 6% by weight nettle fibers for polymer matrix tensile modulus increases by 21%. For the hybrid 1 two-layer composite (6% by weight glass and 6% by weight nettle) and the hybrid 2 three-layer composite (12% by weight glass and 6% by weight nettle), it increases by 80% and 101%, respectively. On the other hand, dynamic mechanical analysis (DMA) has been used to assess the damping properties of the materials. The results showed that the loss factor increased by 6~14% for nettle reinforced composite, by 8~25% for hybrid 1 glass-nettle reinforced composite and by 2~15% for hybrid 2 glass-nettle reinforced composite for frequencies around 1.0~2.0 Hz and around 12 Hz corresponding to vehicle body and suspension natural frequencies, respectively. These results showed that glass fibers can be replaced by nettle fibers without compromising performance. Full article

The stinging nettle Urticadioica L. is a perennial crop with low fertilizer and pesticide requirements, well adapted to a wide range of environmental conditions. It has been successfully grown in most European climatic zones while also promoting local flora and fauna diversity. The cultivation of nettle could help meet the strong increase in demand for raw materials based on plant fibers as a substitute for artificial fibers in sectors as diverse as the textile and automotive industries. In the present review, we present a historical perspective of selection, harvest, and fiber processing features where the state of the art of nettle varietal selection is detailed. A synthesis of the general knowledge about its biology, adaptability, and genetics constituents, highlighting gaps in our current knowledge on interactions with other organisms, is provided. We further addressed cultivation and processing features, putting a special emphasis on harvesting systems and fiber extraction processes to improve fiber yield and quality. Various uses in industrial processes and notably for the restoration of marginal lands and avenues of future research on this high-value multi-use plant for the global fiber market are described. Full article

Nettle is most often studied as a spinning plant, as a source of biochemicals and environmentally safe fungicides. Major studies are mostly conducted on natural samples and plant populations. Prospects for the use of plant biological resources of stinging nettle (Urtica dioica L.) from the Cretaceous south of the Central Russian Upland to create cultivars for a wide range of applications are considered. The aim of the study is to investigate the productivity of fresh weight and its biochemical composition in the variety of stinging nettle Avicenna, created on the basis of the initial material selected in the Belgorod region of Russia and patented in 2019, and new promising cultivars UD 32/06 and UD 12/16. The experiments were carried out by the split plot method with full randomization in four replicates. The cultivars UD 32/06 and UD 12/16 reliably surpass the Avicenna cultivar in the collection of fresh mass weight by 16.6–22.7% and 23.1 to 27.8%, dry weight by 11.4–28.7% and 1.9–32.7%, and seeds by 19.7–32.0% and 23.2–40.0% accordingly. Analysis of variance showed a significant effect of the factor “Cultivar” on the productive traits “Fresh weight yield” (strength influence 87.2%), “Dry weight yield” (strength influence 43.9%), and “Seed yield” (h²x = 61.6%). The content of crude protein in dry weight of the Avicenna and new varieties is 21.1–24.2%, crude fat: 2.5–4.2%, fiber: 12.0–14.8%. High content of ascorbic acid, calcium, phosphorus, iron, and zinc were observed in all material tested. It is concluded that the biological resources of the wild-growing forms of Urtica dioica L. from the European south of Russia are a valuable source material for obtaining varieties, and varieties with high productivity of the aboveground mass and stable seed productivity. The obtained research results prove the usefulness of nettle cultivation. Full article

Stinging nettle (Urtica dioica L.) is a good source of biologically active compounds with proven beneficial health effects. This study aimed to investigate the effect of nettle herb supplementation on chemical composition, including the content of selected minerals and pigments, the in vitro glycemic response, and the cooking and sensory quality of extruded pasta. Tagliatelle-shaped pasta was produced under semi-technical scale by partial replacement of durum wheat semolina with 0, 1, 2, 3, 4, and 5% of lyophilized nettle. The partial substitution with freeze-dried nettle caused a statistically significant (p ≤ 0.05) increase in the content of minerals, especially calcium, iron, potassium, and magnesium in the products. The calcium content in the pasta fortified with 5%-addition of stinging nettle was 175.9 mg 100 g⁻¹ and this concentration was 5.8 times higher than in the control sample. At the same time, high content of chlorophylls and carotenoids (237.58 µg g⁻¹ and 13.35 µg g⁻¹, respectively) was noticed. Enriching pasta with a 0–5% addition of stinging nettle resulted in a statistically significant (p ≤ 0.05) increase in the content of the total dietary fiber (TDF) (from 5.1 g 100 g⁻¹ to 8.82 g 100 g⁻¹) and the insoluble dietary fiber (IDF) (from 2.29 g 100 g⁻¹ to 5.63 g 100 g⁻¹). The lowest hydrolysis index of starch (HI = 17.49%) and the lowest glycemic index (GI = 49.31%) were noted for the pasta enriched with 3% nettle. Full article