Search Results (208)

The objective of this study was to determine the total color change and mass loss that heat treatment with six different combinations of temperature and time induces in ash (Fraxinus excelsior L.), oak (Quercus robur L.) and walnut (Juglans regia L.) wood. As a result, a color palette was established for the three hardwood species, which are of interest for the furniture industry. Each color was associated with the obtained mass loss to present valuable information on how much the mechanical strength of the heat-treated material was affected. This study is of potential interest for furniture designers, as it promotes the color versatility of wood species without the addition of chemical substances. Full article

Ancient walnut trees (Juglans regia L.), revered as “cultural heritage in motion,” have coexisted harmoniously with dense clusters of Tibetan traditional villages for centuries. However, accelerating climate change and expanding human activities along the middle reaches of the Yarlung Tsangpo River have increasingly threatened their survival. To quantitatively evaluate the health of these ancient trees and identify the underlying driving mechanisms, this study developed a remote sensing-enhanced Structural Equation Model (SEM) that integrated satellite-derived ecological indices, land-use intensity, and field-measured morphological and physiological indicators. A total of 135 ancient walnut trees from villages such as Gamai in Jiacha County, Tibet, were examined. Key findings: (1) The SEM demonstrated an excellent model–data fit (Minimum Discrepancy Divided by Degrees of Freedom (CMIN/DF) = 1.372, Root Mean Square Error of Approximation (RMSEA) = 0.053, Tucker–Lewis Index (TLI) = 0.956, and Comparative Fit Index (CFI) = 0.962), confirming its robustness. (2) Among the latent variables, overall condition exerted the strongest influence (weight = 0.360), whereas foliage condition contributed least (0.289). (3) Approximately 35.56% of trees were healthy or sub-healthy, while 61.48% showed varying levels of decline. (4) Tree health was jointly shaped by intrinsic and extrinsic factors, with intrinsic drivers exhibiting stronger explanatory power. Externally, human disturbance negatively affected health, whereas ecological quality was positively associated. These results highlight the effectiveness of integrating remote sensing and SEM for ancient tree assessment and underscore the urgent need for long-term monitoring and adaptive conservation strategies to enhance ecological resilience. Full article

Tannins are key compounds determining the astringency of walnuts. Elucidating the structural characteristics of tannin cells in walnut inner seed coats and the accumulation patterns of esterified catechins (e.g., EGCG and ECG) is of significant importance for both quality regulation of walnuts and the high-value utilization of tannin resources. However, the enzymatic properties and biological functions of walnut tannases (JrTAs) have not been systematically investigated. Thus, the enzymatic characteristics of walnut tannase and its hydrolytic function on tannin-like substances were analyzed. It showed that tannin accumulation in the inner seed coat of ‘Nonghe 1’ walnut was closely associated with the development of tannin cells. During seed coats development, the total tannin content initially decreased and then increased, while the levels of monomeric phenolics related to tannin synthesis (GC, EGC and EC) continuously increased. Two walnut tannase genes, JrTA1 and JrTA2, were cloned and the recombinant proteins were purified. In vitro enzymatic activity tests confirmed that both enzymes effectively hydrolyzed ester-type catechins ECG and EGCG after 20 min of reaction at 40 °C and pH 7.0. Moreover, the transgenic Arabidopsis systems and green tea infusion study demonstrated that JrTA1 and JrTA2 retained their ability to specifically cleave the ester bonds of ester-type catechins in heterologous systems, achieving efficient tannin degradation. This study systematically elucidates the enzymatic functions of JrTAs, which provides a theoretical foundation for the further development and application of walnut tannases. Full article

Background/Objectives: Understanding how plant-derived extracts influence the rheological and sensory behavior of emulsions is crucial for developing stable and consumer-appealing formulations. Although walnut leaf extract (Juglans regia L.) is recognized for its bioactive properties, its structural impact on cosmetic emulsions has not been systematically characterized. This study aimed to investigate the effect of increasing walnut leaf extract concentration on the rheological profile, mechanical integrity during application, and sensory performance of oil-in-water creams. Methods: Four emulsion formulations (F1–F4) containing 0%, 1%, 3%, and 5% walnut leaf extract were prepared using Olivem 1000 and Olivem 300 as emulsifiers. Rheological measurements included amplitude sweep, flow curve, frequency sweep, and thixotropy tests to assess viscoelasticity, flow behavior, and recovery. A sensory evaluation was conducted by trained panelists to correlate rheological parameters with perceived product attributes. Results: All formulations exhibited pseudoplastic, shear-thinning behavior in well-structured cosmetic emulsions during application. The addition of walnut extract significantly modified rheological responses: at 1% concentration, an increase in storage modulus (G′) and shear-thinning ratio (η₀/η∞) indicated structural reinforcement and improved spreadability, whereas higher concentrations (3–5%) led to structural softening and faster thixotropic recovery. The frequency sweep revealed a concentration-dependent shift from elastic- to viscous-dominant behavior. Sensory analysis confirmed these trends, with higher extract levels reducing stickiness and greasiness while enhancing absorption. Conclusions: Walnut leaf extract shows a concentration-dependent influence on the rheological behavior of the emulsions, strengthening the network structure at low levels while promoting softening and faster structural recovery at higher concentrations. The strong correlation between rheological and sensory parameters underscores the potential of walnut extract as a multifunctional ingredient for designing well-structured, non-greasy, and consumer-preferred cosmetic creams. Full article

Walnut (Juglans regia L.) is an important economic and oil-bearing tree species, and the nutritional quality of its kernels is influenced by multiple environmental factors. Elevation is an ecological gradient that integratively reflects variations in environmental conditions such as temperature and light availability and shows a certain degree of correlation with kernel nutritional quality. The aim of this study was to clarify the regulatory effect of elevation on the nutritional quality of walnut kernels in Chongqing and to optimize the layout of high-quality walnut production areas. This study used 181 walnut germplasm resources collected from 16 natural populations (production areas) in Chongqing. Six elevation ranges were defined (I: 200–600 m, II: 600–900 m, III: 900–1200 m, IV: 1200–1400 m, V: 1400–1600 m, VI: 1600–1800 m), and twelve nutritional traits of walnut kernels were systematically analyzed, including total fat, protein, soluble sugar, tannin, saturated fatty acids (stearic acid, palmitic acid, arachidic acid), and unsaturated fatty acids (oleic acid, palmitoleic acid, cis-11-eicosenoic acid, linoleic acid, α-linolenic acid). The results showed that the fat content of walnut kernels was generally higher than 60%, with the highest value in zone VI (62.93%). The protein content was the highest in zone III (17.71%) and the lowest in zone VI (16.06%). Soluble sugar and tannin contents were relatively low, both peaking in zone II (3.10% and 10.85%, respectively). The overall content of saturated fatty acids was low, being slightly higher in zone II, with little variation among components across elevations. Among monounsaturated fatty acids, oleic acid was dominant, showing a decreasing–increasing trend with rising elevation, with the lowest value in zone II (20.98%) and the highest in zone VI (26.93%), while palmitoleic acid and cis-11-eicosenoic acid were maintained at low levels. Polyunsaturated fatty acids were dominated by linoleic acid, ranging from 51.22% to 61.04%, with the highest content in zone II and the lowest in zone VI. Comprehensive evaluation and cluster analysis grouped the six elevation zones into three categories, with zone II showing the best nutritional quality, particularly in terms of soluble sugar, stearic acid, and linoleic acid, while zone I had the lowest score. These findings provide a theoretical basis for the selection of high-quality walnut production areas and the precision cultivation of nutrient-rich walnut fruits, as well as important data support for the scientific planning and high-quality development of the walnut industry in Chongqing. Full article

Scientific research, within the framework of a circular and sustainable economy, has increasingly focused on wild plants and agricultural by-products as valuable sources of bioactive compounds for innovative applications. In this study, the plant species selected for extract preparation and evaluation of their dyeing properties included Isatis tinctoria L., Castanea sativa, Juglans regia L., Rumex crispus L., Arbutus unedo L., and Punica granatum L. Each extract was analyzed to assess its dyeing performance on cotton and other cellulosic fabrics. Cellulose pads dyed with peels of P. granatum extract (PPGE) proved to be versatile and effective, showing potential for use in extending the shelf life of various fruits such as strawberries, apples, cherries, and persimmons. The optimum dyeing condition for cellulose and cotton fabrics was found to be 6% w/v dye. These findings support the development of natural, multifunctional materials suitable for food packaging applications aimed at preserving fresh produce, as well as for sustainable textile dyeing. Full article

Walnut (Juglans regia L.), a critical economic species, experiences substantial declines in fruit quality and yield due to Walnut Leaf Scorch (WLS). This issue is particularly severe in the Xinjiang Uygur Autonomous Region (XUAR)—one of Asia’s leading walnut-producing regions. To mitigate the disease, timely and efficient monitoring approaches for detecting infected trees and quantifying their disease severity are in urgent demand. In this study, we explored the feasibility of developing a predictive model for the precise quantification of WLS severity. First, five 4-mu (1 mu = 0.067 ha) sample plots were established to identify infected individual trees, from which the WLS Disease Index (DI) was calculated for each tree. Concurrently, hyperspectral data of individual trees were acquired via an unmanned aerial vehicle (UAV) platform. Second, DI estimation models were developed based on the Random Forest (RF) and Support Vector Machine (SVM) algorithms, with each algorithm optimized using either Grid Search (GS) or a Genetic Algorithm (GA). Finally, four integrated models (GS-RF, GA-RF, GS-SVM, and GA-SVM) were constructed and systematically compared. The results showed that the Genetic Algorithm-optimized SVM model (GA-SVM) exhibited the highest predictive accuracy and robustness, achieving a coefficient of determination (R²) of 0.6302, a Root Mean Square Error (RMSE) of 0.0629, and a Mean Absolute Error (MAE) of 0.0480. Our findings demonstrate the great potential of integrating UAV-based hyperspectral remote sensing with optimized machine learning algorithms for WLS monitoring, thus offering a novel technical approach for the macroscopic, rapid, and non-destructive surveillance of this disease. Full article

Walnut male flowers (WMFs) are important by-products of walnut production. Studies on the nutritional quality of WMFs have predominantly focused on a single variety or region, and scientific information on different varieties is limited. In this study, ten walnut male flower (WMF) samples were evaluated and compared to assess their nutritional composition, bioactive contents, and antioxidant capacity. All WMF varieties were rich in protein, minerals, and amino acids, with leucine being the most abundant amino acid. All varieties exhibited low fat content and a favorable Na/K ratio. Additionally, they contained high levels of polyphenols and flavonoids, which were associated with strong antioxidant capacity. The variety seemed to exert a greater influence than the region on the nutritional composition and bioactive contents of WMFs. Moreover, polysaccharide, starch, soluble sugar, polyphenol, and fat might serve as potential markers for distinguishing different WMF varieties. This study provides a reference for the development and utilization of WMFs. Full article

The sustainable valorisation of agro-industrial by-products offers a promising pathway to address global protein demand while supporting circular food systems. This study explored the biotechnological potential of pumpkin (Cucurbita pepo), sunflower (Helianthus annuus), and walnut (Juglans regia L.) oilseed cakes as substrates for developing vegan yoghurt-like fermented beverages. Each formulation was fermented with Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, and comprehensively evaluated for composition, functionality, sensory properties, and bioactivity. The oilseed-based beverages exhibited protein levels between 3.7–4.6%, fibre content up to 1.9%, and reduced syneresis (14–18%) compared with the commercial almond-based product (21.5%). The walnut-based variant (WOCY) showed the highest total polyphenol content (1108.97 mg GAE kg⁻¹) and antioxidant activity (412.54 mg Trolox kg⁻¹ DPPH; 51.5 mg TE g⁻¹ DW ABTS), surpassing both the almond-based vegan yoghurt (238.82 mg GAE kg⁻¹) and dairy reference (96.10 mg GAE kg⁻¹). Preliminary sensory profiling through the Check-All-That-Apply (CATA) method indicated that pumpkin- and walnut-based samples were most associated with “creamy texture,” “nutty aroma,” and “very pleasant” descriptors, achieving acceptance comparable to or higher than conventional yoghurts. Microbiological analyses confirmed product safety and high viable cell counts (<10⁸ CFU mL⁻¹) after 14 days of storage. Oilseed cakes serve as efficient substrates for producing nutrient-dense, antioxidant-rich, and sensorially appealing plant-based fermented beverages, supporting functional food innovation and promoting circular bioeconomy through the sustainable valorisation of agro-industrial by-products. Full article

Synthetic anthelmintic drugs not only contribute to the development of pathogen resistance and environmental pollution but also to the development of pathogen resistance. Therefore, identifying the anthelmintic properties of widely used medicinal plants could be of great practical interest to veterinary and human medicine. In our experiment, we evaluated the in vitro survivability of the noninvasive and invasive (L_1–2 and L_3, respectively) larvae of Strongyloides papillosus and Haemonchus contortus subject to aqueous solutions of ethanolic tinctures of traditional medicinal plants (46 species). Most of the plant species we studied belonged to the families Asteraceae (Achillea millefolium, Arctium lappa, Artemisia absinthium, Bidens tripartita, Calendula officinalis, Cynara cardunculus var. scolymus, Echinacea purpurea, Helichrysum arenarium, Inula helenium, Matricaria chamomilla, Silybum marianum, Tanacetum vulgare, Taraxacum officinale, Tragopogon porrifolius), Rosaceae (Agrimonia eupatoria, Fragaria vesca, Sanguisorba officinalis), and Lamiaceae (Leonurus cardiaca, Mentha × piperita, Origanum vulgare, Salvia officinalis, Thymus vulgaris). Other plant families were represented by 1–3 species: Fabaceae (Glycyrrhiza glabra, Hedysarum alpinum, Trifolium pratense), Salicaceae (Populus nigra, P. tremula, Salix alba), Fagaceae (Quercus robur), Betulaceae (Betula pendula), Juglandaceae (Juglans regia), Rhamnaceae (Frangula alnus), Acoraceae (Acorus calamus), Apiaceae (Foeniculum vulgare), Caprifoliaceae (Valeriana officinalis), Cucurbitaceae (Cucurbita pepo), Equisetaceae (Equisetum arvense), Ericaceae (Vaccinium vitis-idaea), Gentianaceae (Centaurium erythraea), Hypericaceae (Hypericum perforatum), Malvaceae (Althaea officinalis), Plantaginaceae (Linaria vulgaris, Plantago major), Poaceae (Zea mays), Polygonaceae (Polygonum aviculare), and Ranunculaceae (Nigella sativa). We determined Artemisia absinthium, Inula helenium, Matricaria chamomilla, Salvia officinalis, and Populus nigra, whose aqueous solutions of alcohol tinctures demonstrated nematocidal properties. The other plants we studied did not affect the viability of parasitic nematode larvae. Full article

Plants are a valuable source of natural compounds with diverse applications. Recently, increased attention has focused on waste products from the agricultural industry, including walnut husk. Given its potential as a sustainable source of bioactives, this work characterizes the alcoholic Juglans regia “Sorrento” walnut husk extract (WHE). The extract’s phenolic content, antioxidant activity, and phytochemical composition were evaluated using spectrophotometry and UHPLC-HRMS-based untargeted metabolomics analysis. WHE exhibited a high total phenolic content (TPC = 1.45 ± 0.03 mg GAE/g dry extract) and a rich profile of phenolic acids, flavonoids, and tannins. Given this composition, WHE’s biological activity was further tested in an in vitro human keratinocyte (HaCaT) model. At the concentration of 10 μg/mL, WHE showed no cytotoxicity and displayed significant antioxidant properties by modulating detoxifying proteins such as Nrf2. WHE also influenced mitochondrial metabolism, increased maximum respiration, preserved barrier integrity, and activated pathways for epithelial homeostasis. Overall, this study highlights the bioactivity of the J. regia “Sorrento” walnut husk extract. These findings support the valorization of walnut husk as a sustainable source of bioactives for dermatological and cosmetic products. Full article

The green husk of Juglans regia L. is rich in bioactive phytochemicals and exhibits various biological activities. This study aimed to investigate the skin anti-aging potential of the green husk of J. regia by determining the optimal extraction conditions using a Box–Behnken Design (BBD), targeting elastase inhibition, and by correlating variations in phenolic compounds identified through metabolomic analyses with changes in the extraction conditions. Ultrasonic-assisted extraction was employed along with natural deep eutectic solvents (NADES). Three levels of three independent variables (NADES/H₂O ratio, temperature, and extraction time) were incorporated into the BBD. Phenolic compounds were determined semi-quantitatively using liquid chromatography–quadrupole time-of-flight mass spectrometry (LC-q-TOF/MS), while elastase inhibition was evaluated by spectroscopic methods. Quadratic response surface models were proposed based on the BBD model adequacy test using multiple regression analysis. It was determined that the optimum conditions for maximizing phenolic content and elastase inhibition were 99.79% ethanol, 51.30 °C temperature, and 49.58 min, in which case the desirability score was 1. Metabolomic analysis identified 41 phenolic compounds across 27 ontological groups, with 24 compounds showing a semi-quantitative increase. Consequently, the waste green husk of J. regia demonstrated enhanced anti-aging potential due to the higher content and diversity of phenolic compounds. Full article

Branch canker and dieback, caused by Botryosphaeriaceae and Diaporthaceae, is a major disease of walnut (Juglans regia L.) worldwide. In Chile, the impact of pruning wound age and timing on susceptibility to these pathogens in walnut trees remains poorly understood. During June–July (2023) and June–July (2024), this study assessed the effect of pruning wound age of the walnut cv. Chandler on infection by seven fungal species and simultaneously tracked seasonal conidial release of Botryosphaeriaceae spp. in the Maule Region, Chile. Lignified twigs were artificially inoculated at 1, 15, 30, and 45 days after pruning, and necrotic lesion lengths were measured six months post-inoculation. All fungal isolates caused significantly longer lesions than the control (p < 0.0001), with Diplodia mutila, Neofusicoccum nonquaesitum, and N. parvum being the most aggressive. At the same time, Dothiorella sarmentorum and Diaporthe species (Diaporthe australafricana, Di. foeniculina, and Di. patagonica) produced the smallest lesions. Susceptibility decreased with increasing wound age, with a significant interaction between fungal species and pruning wound age. Spore trapping of Botryosphaeriaceae revealed that dispersal was positively associated with rainfall (r = 0.81, p < 0.0001), relative humidity (r = 0.51 to 0.61, p < 0.05) and average temperature (r = 0.32 to 0.58, p < 0.05), but negatively or not significantly correlated with maximum temperature (r = −0.59 to −0.79, p > 0.05). These results demonstrate that rainfall or relative humidity, moderate conditions, and favor conidial release. At the same time, infection risk declines with wound age, underscoring the need to adjust pruning schedules and preventive strategies to reduce disease risk in walnut orchards. Full article

Walnut (Juglans regia L.) is a significant nut crop in the southern regions of Kazakhstan; however, its productivity is substantially limited by fungal and bacterial diseases. Therefore, a phytopathological investigation was conducted in 2023–2024 in the Almaty and Turkestan regions, including field monitoring, pathogen isolation, molecular identification, and pathogenicity testing. Field monitoring revealed that symptoms of brown spot, walnut canker, walnut blight, bacterial blight, and crown gall were widespread. The overall disease incidence ranged from 8% to 30%, while the disease severity index varied from 15% to 70% across the surveyed sites. Pure cultures of pathogens were isolated from 69 samples, and their morphology was characterized. Molecular identification through sequencing of universal genetic loci (the internal transcribed spacer for fungi and 16S ribosomal RNA for bacteria) revealed the presence of the fungal species Alternaria alternata and Fusarium incarnatum, as well as the bacterial species Pantoea agglomerans and Xanthomonas arboricola pv. juglandis. Pathogenicity testing confirmed the virulence of the identified pathogens, which induced characteristic symptoms of brown spot, walnut canker, and walnut blight, consistent with those observed in the field. These findings have considerable practical significance for improving phytosanitary monitoring and protection systems in walnut plantations, thereby facilitating disease outbreak prediction and the development of effective quarantine measures. Full article

Walnuts (Juglans regia L.) are an economically important woody crop, but spring frost poses a serious threat to their growth and productivity. However, the molecular mechanisms underlying walnut responses to freezing stress remain largely unknown. In this study, transcriptome analyses were performed on cold-tolerant and cold-sensitive walnut varieties subjected to freezing stress. A total of 9611 differentially expressed genes (DEGs) responsive to freezing stress were obtained, of which 2853 were common up-regulated and 2880 were common down-regulated in both varieties. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed 15 significantly enriched pathways in both varieties, including flavonoid biosynthesis. A simplified walnut flavonoid biosynthesis pathway was constructed, encompassing 36 DEGs encoding 13 key enzymes, demonstrating that flavonoid biosynthesis in walnut is significantly activated under freezing stress. Furthermore, weighted gene co-expression network analysis (WGCNA) identified a regulatory network centered on the JrCBF genes and uncovered 34 potential interacting genes. Collectively, these findings provide novel insights into the molecular responses of walnut to freezing stress and establish a foundation for elucidating the mechanisms underlying walnut cold tolerance. Full article