Juglans Mandshurica Research Articles

Allometric biomass equations for 12 tree species in coniferous and broadleaved mixed forests, Northeastern China.

Understanding forest carbon budget and dynamics for sustainable resource management and ecosystem functions requires quantification of above- and below-ground biomass at individual tree species and stand levels. In this study, a total of 122 trees (9–12 per species) were destructively sampled to determine above- and below-ground biomass of 12 tree species (Acer mandshuricum, Acer mono, Betula platyphylla, Carpinus cordata, Fraxinus mandshurica, Juglans mandshurica, Maackia amurensis, P. koraiensis, Populus ussuriensis, Quercus mongolica, Tilia amurensis and Ulmus japonica) in coniferous and broadleaved mixed forests of Northeastern China, an area of the largest natural forest in the country. Biomass allocation was examined and biomass models were developed using diameter as independent variable for individual tree species and all species combined. The results showed that the largest biomass allocation of all species combined was on stems (57.1%), followed by coarse root (21.3%), branch (18.7%), and foliage (2.9%). The log-transformed model was statistically significant for all biomass components, although predicting power was higher for species-specific models than for all species combined, general biomass models, and higher for stems, roots, above-ground biomass, and total tree biomass than for branch and foliage biomass. These findings supplement the previous studies on this forest type by additional sample trees, species and locations, and support biomass research on forest carbon budget and dynamics by management activities such as thinning and harvesting in the northeastern part of China.

The results of the introduction of Juglans mandshurica Maxim. into the oak-woods of the Khopyor region

An analysis of the results of the introduction of Juglans mandshurica Maxim. into the flood-plain oak-woods of the Khopyor is conducted. The total bioecological assessment and prospects of the introduction into the natural flood-plain oak-woods of the Middle Khopyor region for the enrichment of their species composition with the aim of enhancing the sustainability of these ecosystems and optimization of their ecological functions are given. The compliance of the environmental conditions of the growth of introduced stands in the middle reaches of the Khopyor River, original within the natural distribution area is found. Alongside with the identified typical directions of reduction in the indicators of the stability and productivity of this breed in introduced centres in comparison with the natural areas there detected trends in increasing the resistance of the species in the succeeding generations, as a result of clone variability, a selection of species with a high vital potential and adaptive capacity.

Antifatigue, Antioxidant and Immunoregulatory Effects of Peptides Hydrolyzed from Manchurian Walnut (Juglans mandshurica Maxim.) on Mice

Abstract: The Manchurian walnut (Juglans mandshurica Maxim.) is rich in proteins, whereas this resource has not been used efficiently. The antifatigue, antioxidative and immunoregulatory effects of Manchurian walnut hydrolysate peptides (MWHPs) were evaluated in this study. MWHPs with a degree of hydrolysis of 32.23% were ultrafiltered and divided into three fractions, namely, high (> 10 kDa), medium (3–10 kDa), and low molecular weight ( Supported by National High Technology Research and Development Program (No. 2013AA102206-2)

Protein Hydrolyzates from Changbai Mountain Walnut (Juglans mandshurica Maxim.) Boost Mouse Immune System and Exhibit Immunoregulatory Activities.

The Changbai Mountain walnut (Juglans mandshurica Maxim.) is a rich source of essential amino acids. Walnut dregs are byproducts of edible oil production and primarily used as fodder and fertilizers. We systematically examined the effect of three types of walnut protein hydrolyzates—albumin, glutelin, and globin—on the immune system of mice and aimed to provide the theoretical basis for developing and utilizing J. mandshurica Maxim. protein resources. In comparison with the normal control mice, those treated with different doses of walnut proteins showed improved immune indices, including organ index, spleen lymphocyte proliferation, macrophage activity, number of CD4+ and CD8+ T cells, immunoglobulin A (IgA) and secretory IgA content, and mRNA and protein expression levels of cytokine factors. Our results indicated that these walnut proteins may have positive effects on the immune system and perform their immunomodulatory functions by inducing splenic enlargement. These findings support the use of walnut proteins as nutritional sources to boost the immune system.

Alkaloids from Juglans Mandshurica maxim induce distinctive cell death in hepatocellular carcinoma cells

The aim of this work was to further investigate the anticancer potential of Juglans mandshurica Maxim, including the separation of active constituents and their anti-proliferative effects with underlying mechanism of action. Five alkaloids (1–5) were isolated from the bark of J. mandshurica. Among them, 1 showed the highest cytotoxic activities against Hep3B and HepG2 cells with an IC50 values of 61.80 and 56.24 μM, respectively. Therefore, the cellular mechanism involved 1 was subsequently studied. Our results showed that 1 markedly caused apoptosis and autophagy, but without cell cycle arrest in HepG2 cells. Interestingly, only autophagic cell death was induced in 1-treated Hep3B cells. It is concluded that the isolated alkaloids exerted a certain anti-hepatoma potential, and our results may provide a basis for the further investigation of the alkaloids extracted from J. mandshurica.

A new diarylheptanoid and a new diarylheptanoid glycoside isolated from the roots of Juglans mandshurica and their anti-inflammatory activities

A new diarylheptanoid, (2S,3S,5S)-2,3,5-trihydroxy-1,7-bis(4-hydroxy- 3-methoxyphenyl)heptane (1), and a new diarylheptanoid glycoside, (2S,3S,5S)-2,3-dihydroxy-5-O-β-d-xylopyranosyl-7-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)heptane (2), together with three known compounds, rhoiptelol C (3), rhoiptelol B (4) and 3′,4″-epoxy-2-O-β-d-glucopyanosyl-1-(4-hydroxyphenyl)- 7-(3-methoxyphenyl)heptan-3-one (5) were isolated from the roots of Juglans mandshurica (Juglandaceae). The structures of compounds 1 and 2 were identified based on HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Compounds 1–5 were assayed for their inhibitory effects on the production of NO, TNF-α and IL-6 in LPS-stimulated RAW264.7 cells.

Fabrication and characterization of reversible thermochromic wood veneers

Leuco dyes are widely used as functional materials for their thermosensitive chromogenic nature. The influences of thermochromic compounds and impregnation processing conditions on thermochromic wood veneer properties were investigated in this paper. The thermochromic compounds included thermochromic dye (ODB-2), color developer (bisphenol A) and solvent (1-tetradecanol). To achieve the maximum color change, the optimum mixing ratio of ODB-2 to bisphenol A to 1-tetradecanol was 1:2:60. Juglans mandshurica veneers were ultrasonically impregnated with reversible thermochromic compound suspensions. Analysis of variance showed that the influences of impregnation parameters on veneer color change were significant at the 0.05 level. The optimum thermochromic wood veneer can be obtained by impregnating with a thermochromic compound suspension for 2.0 min at 65 °C. In this paper, the thermochromic properties of wood veneers were evaluated, and functional thermochromic veneers exhibited excellent properties and thermostability.

Temporal and Spatial Variations of Active Ingredients in Juglans mandshurica Maxim and Their Anti-tumor Activity

Temporal and Spatial Variations of Active Ingredients in Juglans mandshurica Maxim and Their Anti-tumor Activity

The effect of low-temperature event on the survival and growth of Juglans mandshurica seedlings within forest gaps

In forest ecosystems, gap formation changes the allocation of abiotic resources and thus affects the survival and growth of understory plants. However, how tree seedling survival and growth respond to low-temperature events and the influencing mechanisms remain unclear. To clarify how low-temperature event limits the survival and growth of tree seedlings in the montane regions of eastern Liaoning Province, northeast China, we investigated temperature and light intensity within secondary forest gaps, and the survival and growth of Juglans mandshurica seedlings after a low-temperature event in the spring of 2014. Damage to seedlings due to low temperature significantly varied in different aspects. Seedlings in gaps on southeast-facing slopes were the most seriously damaged, followed by those in gaps on northeast-facing slopes. In contrast, seedlings in west-facing gaps and in control plots without slope aspect were not damaged. The freezing injury index for seedlings was negatively correlated with minimum temperature (r = − 0.608, P 0.05). The extent of seedling damage was directly related to slope aspect. Low temperature and high light intensity were found to be the dominant factors affecting extent of damage to seedlings on southeast- and northeast-facing slopes.

Converting larch plantations to mixed stands: Effects of canopy treatment on the survival and growth of planted seedlings with contrasting shade tolerance

Larch (Larix spp.) plantations are important for timber production in Northeast China, but this monoculture practice has led to problems such as decreased soil fertility and water-holding capacity. To examine the possibility of gradually converting pure larch plantations to mixed stands by small-scale canopy regulation, we planted seedlings of two species with contrasting shade tolerance, light-demanding Manchurian walnut (Juglans mandshurica Maxim.) and shade-tolerant Korean spruce (Picea koraiensis Nakai), in larch plantations with four different canopy retention intensities (larger gap, 160 m2; smaller gap, 45 m2; thinning, 25% intensity based on basal area; and control, forest understory). After two growing seasons, we found that both species had higher survival rates and growth rates in larger gaps than in forest understories, but the detailed responses to treatments differed between species. Manchurian walnut responded strongly to larger gaps but insensitively to other treatments, especially with respect to biomass accumulation. In contrast, Korean spruce responded gradually with increasing canopy openness. However, canopy treatments had almost no effect on non-structural carbohydrate (NSC) concentration, biomass allocation, and NSC pool allocation, which only differed between species. Our findings indicated that the two species of contrasting shade-tolerance were able to survive and grow in larch plantations, and a small-scale canopy treatment, especially creating gaps of ∼160 m2 in size, could significantly improve seedling survival and growth during the first two years. Therefore, enrichment planting in conjunction with a low-intensity canopy regulation may play an effective role in converting larch plantations to mixed stands while maintaining continuous stand functions during the conversion process.

Cytotoxic lignans from the barks of Juglans mandshurica

Phytochemical investigation of the barks of Juglans mandshurica Maxim led to the isolation, purification, and identification of one new lignan named Juglansol A (1), along with nine known compounds (2–10). Their structures were determined by the results of UV, IR, CD, HRESIMS, 1D, and 2D NMR spectroscopic analysis. Compounds 1–10 were evaluated for their cytotoxicities against A549, HepG2, Hep3B, Bcap-37, and MCF-7 cell lines. The results showed that compound 2 possessed stronger cytotoxicities against the tested tumor cell lines compared with positive control 5-fluorouracil.

A self-assembled polyjuglanin nanoparticle loaded with doxorubicin and anti-Kras siRNA for attenuating multidrug resistance in human lung cancer

Lung cancer is a leading cause of cancer-associated mortality worldwide, which has a low survival rate. Multidrug resistance (MDR) is a major obstacle that hinders the treatment of lung cancer. Doxorubicin (DOX) is an anthracycline glycoside antibiotic, having a broad spectrum of anticancer activity against various solid tumors. Juglanin is a natural production, mainly extracted from green walnut husks of Juglans mandshurica, exhibiting various bioactivities. Here, we demonstrated that the combination of drug, gene and nanoparticle overcame MDR, inhibiting lung cancer progression. A novel nanoparticular pre-chemosensitizer was applied to develop a self-assembled nanoparticle formula of amphiphilic poly(juglanin (Jug) dithiodipropionic acid (DA))-b-poly(ethylene glycol) (PEG)-siRNA Kras with DOX in the core (DOX/PJAD-PEG-siRNA). The formed nanoparticles, appeared spherical shape, had mean particle size of 81.8 nm, and the zeta potential was −18.62 mV. The in vitro drug release results suggested that a sustained release was observed in DOX/PJAD-PEG-siRNA nanoparticles compared to the free DOX. Jug could improve the cytotoxicity of DOX to cancer cells with MDR. Oncogene, Kras, was dose-dependently reduced by treatment of DOX/PJAD-PEG-siRNA nanoparticles. Additionally, P-glycoprotein (MDR1) and c-Myc, contributing to tumor progression, were suppressed by the nanoparticles, while p53 was improved in drug-resistant cells. Colony formation analysis suggested that DOX/PJAD-PEG-siRNA nanoparticles showed the most effective role in reducing cancer cell proliferation. In vivo, DOX/PJAD-PEG-siRNA nanoparticles reduced tumor growth compared to the free DOX, accompanied with reduced KI-67 and enhanced TUNEL positive levels in drug-resistant xenografted nude mice. Thus, the findings above indicated that juglanin, as a chemosensitizer, potentiate the anti-cancer role of DOX in drug-resistant cancer cells. And the nanoparticles exhibited stronger antitumor efficiency, suggesting potential value in the treatment of lung cancer.

The PCA index for measuring functional diversity and its application to Juglans mandshurica communities in the Beijing mountains, China

Methods for measuring functional diversity are essential for functional studies of plant communities. A useful method, the PCA index, based on principal component analysis ordination of functional trait data was introduced and applied to functional diversity analysis of Juglans mandshurica communities in the Beijing Mountains. Thirty-five [Formula: see text] quadrats were established in Juglans mandshurica communities. Species composition, functional traits and environmental factors were measured and recorded. The four common indices, FAD, MFAD, FDp and FDc, were used and compared with the PCA index in the analysis. The results showed that the PCA index was successful in quantifying functional diversity and describing its relationships with environmental variables; therefore, it was an effective index in functional diversity analyses. Functional diversity in Juglans mandshuricacommunities varied widely. Elevation and aspect were the key factors affecting functional diversity in communities. Functional diversity increased with elevation increases and with the change in aspect from North to South. Functional diversity was significantly correlated with species richness and heterogeneity.

Phenotypic Plasticity and Respond of Juglans mandshurica Seedling under Different Light Environments

Phenotypic Plasticity and Respond of Juglans mandshurica Seedling under Different Light Environments

One new 1,4-napthoquinone derivative from the roots of Juglans mandshurica

A new 1,4-napthoquinone derivative, namely (S)-(-)-3-(8-hydroxy-1,4-dioxo-1,4-dihydro-naphthalen-2-yl)-3-(4-hydroxy-3-methoxyphenyl)-propionic acid methyl ester (1), was isolated from the roots of Juglans mandshurica Maxim. The structure was identified based on HR-ESI-MS, 1D and 2D NMR spectroscopic methods.

Comparative study of the leaf transcriptomes and ionoms of Juglans regia and its wild relative species Juglans cathayensis

Juglans regia ‘Yuanfeng’ is an elite walnut cultivar in China. Juglans cathayensis, a close relative species of Juglans regia originated from China, possesses some superior traits such as strong disease resistance and high fruit number per branch. So far, transcriptomes of either J. regia or J. cathayensis have not been studied and made available to public yet. In the present study, the transcriptomes of J. regia and J. cathayensis leaves were profiled using Illumina HiSeq 2000 platform. A total of 41,914 unigenes were obtained from the combined clean reads of J. regia and J. cathayensis with an average length of 1363 bp and 2529 differentially expressed genes (DEGs) were detected. Gene annotation analyses revealed that 38,483 unigenes (91.81%) were annotated in at least one of the five databases such as Gene Ontology (GO), etc. Meanwhile, the Ca, Mg, Fe, Zn, K and protein contents in the leaves of J. regia and J. cathayensis were compared and significant differences between J. regia and J. cathayensis in terms of the Ca, Mg, Fe and protein contents were discovered. In addition, DEGs associated with the Ca, Mg and Fe content variations between J. regia and J. cathayensis were investigated. Our comparative transcriptomes’ analysis between J. regia and J. cathayensis could provide a useful resource for genetic characterization and improvements of J. regia.

Multiconstituent identification in root, branch, and leaf extracts of Juglans mandshurica using ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry

As a traditional medicinal plant, Juglans mandshurica has been used for the treatment of cancer. Different organs of this plant showed anti-tumor activity in clinic and laboratory. Comparative identification of constituents in different plant organs is essential for investigation of the relationship between chemical constituents and pharmacological activities. For this aim, the roots, branches, and leaves of J. mandshurica were extracted with 50% v/v methanol and then subjected to ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry analysis conducted under low and high energy. As a result, we have to date identified 111 compounds consisting of 56 tannins, 29 flavonoids, 13 organic acids, 8 naphthalene derivatives, and 5 anthracenes. Five compounds, namely, diquercetin trihydroxy-truxinoyl-glucoside, two quercetin kaempferol dihydroxy-truxinoyl-glucosides, syringoyl-tri-galloyl-O-glucose, and dihydroxy-naphthalene syringoyl-glucoside, were tentatively identified as new compounds. Of the compounds identified, 76 were found in the root extract, 67 in the branch extract, and 37 in the leaf extract. Only six compounds including four organic acids and two tannins were found in all three extracts. We developed a rapid and sensitive ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry approach to identify multiple constituents of complex extracts without separation and ion selection. The results presented provide useful information on further research of the bioactive compounds of J. mandshurica.

Identification of Polar Constituents in the Decoction of Juglans mandshurica and in the Medicated Egg Prepared with the Decoction by HPLC-Q-TOF MS².

As a folk medicinal plant, Juglans mandshurica has been used for the treatment of cancer in China and Korea. Traditionally, J. mandshurica is decocted together with chicken eggs. Both the decoction and medicated eggs possess anti-tumor properties. Clarifying the constituents of the decoction and absorbed by the medicated eggs is essential for the investigation of the active principles of J. mandshurica. Herein, the medicated eggs were prepared by decocting raw chicken eggs, having unbroken shells, with the decoction of J. mandshurica. A systematic investigation of the chemical profile of the J. mandshurica decoction and the medicated egg extraction was conducted by HPLC-Q-TOF-MS2. In total, 93 peaks, including 45 tannins, 14 naphthalene derivatives, 17 organic acids, 3 diarylheptanoids, 4 lignans, 3 anthraquinones, 1 flavonoid glycoside, 3 amino acids, and 3 nitrogenous compounds, were tentatively identified in the decoction. In the medicated egg extraction, 44 peaks including 11 organic acids, 3 amino acids, 3 nitrogenous compounds, 8 naphthalene derivatives, 3 diarylheptanoids, 15 tannins, and 1 lignan were tentatively identified. The chemical profile presented provided a detailed overview of the polar chemical constituents in J. mandshurica and useful information for the research of bioactive compounds of this plant.

Rodent-mediated seed dispersal of Juglans mandshurica regulated by gap size and within-gap position in larch plantations: Implication for converting pure larch plantations into larch-walnut mixed forests

Abstract Larch (Larix spp.) is planted extensively after clear-cut of secondary forests in Northeast China to satisfy the enormous timber demands. However, some serious problems arise in larch plantations (LPs) due to mono-species composition, such as a decline in soil fertility and acidification of surface runoff. Converting pure LPs into larch-broadleaf mixed forests would resolve these issues. Since larch-walnut mixed forests are mutually beneficial, it is crucial to promote the regeneration of Juglans mandshurica in LPs. Rodent-mediated seed dispersal of J. mandshurica determines the regeneration success or failure and is closely related to stand structure. Forest gaps are formed by an uneven thinning that changes stand structure in plantation management; the gap size and within-gap position are two key characteristics that affect tree regeneration by changing the micro-environment. We hypothesized that rodent-mediated walnut seed dispersal were strongly influenced by these two key factors. The field trial was conducted by releasing tagged J. mandshurica seeds in two sizes of artificial gaps in LPs (small and medium gaps) and at four positions (south, north, east and west) of the gap edges. The seed releases were conducted at three stages of seed rain (early, middle and final stages) during two continuous growing seasons. Our results showed that only the seed removal rate was significantly affected by gap size and within-gap position; the rate in medium gaps was significantly higher than that in small gaps (Wald = 24.57, df = 1, P

Genetic diversity and population structure in the narrow endemic Chinese walnut Juglans hopeiensis Hu: implications for conservation

The conservation of narrow endemic species relies on accurate information regarding their population structure. Juglans hopeiensis Hu (Ma walnut), found only in Hebei province, Beijing, and Tianjin, China, is a threatened tree species valued commercially for its nut and wood. Sequences of two maternally inherited mitochondrial markers and two maternally inherited chloroplast intergenic spacers, three nuclear DNA sequences, and allele sizes from 11 microsatellites were obtained from 108 individuals of J. hopeiensis, Juglans regia, and Juglans mandshurica. Haplotype networks were constructed using NETWORK. Genetic diversity, population differentiation, and analysis of molecular variance (AMOVA) were used to determine genetic structure. MEGA was used to construct phylogenetic trees. Genetic diversity of J. hopeiensis was moderate based on nuclear DNA, but low based on uniparentally inherited mitochondrial DNA and chloroplast DNA. Haplotype networks showed that J. hopeiensis haplotypes were different than haplotypes found in J. regia and J. mandshurica. Allelic variants in nuclear genes that were shared among J. hopeiensis populations were not found in J. regia or J. mandshurica. Sampled populations of J. hopeiensis showed clear genetic structure. The maximum parsimony (MP) tree showed J. hopeiensis to be distinct from J. mandshurica but threatened by hybridization with J. regia and J. mandshurica. J. hopeiensis populations are strongly differentiated from sympatric Juglans species, but they are threatened by small population sizes and hybridization.