A review of "plant gold" Eucommia ulmoides Oliv.: A medicinal and food homologous plant with economic value and prospect

Comparison of Anti-Renal Fibrosis Activity of Eucommiae cortex Extract and Its Microbial Fermentation Products

Background: Renal fibrosis is a common pathological feature of all progressive chronic kidney disease (CKD). Eucommiae cortex (EC) is a valuable economic tree species endemic to China. The microbial fermentation of Chinese medicines can release their active ingredients as effectively as possible or produce new active ingredients with enhanced efficacy and reduced toxic side effects; Methods: The microbial fermentation of EC can produce pinoresinol (Pin) and dehydrodiconiferyl alcohol (DA). In this study, C57 BL/6 mice were fed a diet containing 0.2% adenine, resulting in a model of chronic kidney disease. The effects of EC and EC ferment (ECF) on CKD were explored by the exogenous supplementation of EC and ECF; Results: The results of the study showed that exogenous supplementation with EC and ECF suc-cessfully reduced creatinine and urea nitrogen levels, down-regulated the expression levels of TGF-β1, α-SMA, Smad3, and phospho-Smad3 in the TGF-β1/Smad signaling pathway, and ameliorated renal fibrosis; Conclusions: Both EC and ECF may have reno-protective effects and provide a reference for relevant clinical drug development.

The Role of Ferroptosis in Osteoporosis and Advances in Chinese Herbal Interventions

OP, a systemic bone disorder marked by reduced bone mass and heightened fracture risk, poses a significant global health burden, particularly among aging populations. Current treatments, including bisphosphonates and calcium supplementation, are limited by adverse effects and incomplete efficacy. Emerging research highlights ferroptosis-an iron-dependent cell death driven by lipid peroxidation-as a critical contributor to OP pathogenesis, characterized by dysregulated iron metabolism, oxidative stress, and lipid peroxide accumulation, which disrupt bone remodeling by impairing osteoblast function and enhancing osteoclast activity. This review elucidates the mechanistic interplay between ferroptosis and OP subtypes (diabetic osteoporosis (DOP), glucocorticoid-induced (GIOP), and postmenopausal osteoporosis (PMOP)) and evaluates the efficacy of Chinese herbal interventions in mitigating ferroptosis-driven bone loss. Key findings reveal that excess iron exacerbates lipid peroxidation via the Fenton reaction, while glutathione peroxidase 4 (GPX4) inactivation and system Xc- inhibition amplify oxidative damage. In DIOP, hyperglycemia-induced ROS and advanced glycation end products suppress osteogenesis, countered by melatonin and naringenin via nuclear factor -related factor 2 (Nrf2)/GPX4 activation. GIOP involves dexamethasone-mediated GPX4 downregulation, mitigated by exosomes and melatonin through phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling. PMOP driven by estrogen deficiency-induced iron overload is alleviated by aconitine and icariin (ICA) via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and signal transducer and activator of transcription 3 (STAT3) pathways. Chinese herbs, including active compounds (quercetin, gastrodin, ICA, etc.) and formulations (Bugu Shengsui Capsule, Erxian Decoction (EXD), etc.), regulate iron metabolism, enhance antioxidant defenses (Nrf2/heme oxygenase 1(HO-1)), and inhibit lipid peroxidation, effectively restoring bone homeostasis. These findings underscore ferroptosis as a pivotal mechanism in OP progression and highlight the therapeutic promise of Chinese herbs in bridging traditional medicine with modern mechanistic insights. Future research should prioritize elucidating precise molecular targets, optimizing formulations, and validating clinical efficacy to address current therapeutic gaps.

Eucommiae cortex Comprehensive Phytochemical Analysis Connected with Its In Vitro Anti-Inflammatory Activity in Human Immune Cells

Eucommia ulmoides Oliv., commonly known as "plant gold", is a species of the Eucommiaceae family, native to East Asia and widely utilized in medicine, food, and the chemical industry. In Traditional Chinese Medicine, the bark of E. ulmoides plays a special role, used to nourish the liver and kidneys and to strengthen tendons and bones. Due to its extensive pharmacological profile, including anti-inflammatory, antioxidant, hypoglycemic, hypotensive, and cardio- and neuroprotective effects, there has been growing interest in elucidating the molecular mechanisms underlying its biological effects. However, many of these mechanisms remain poorly understood to date. This study analyzed the phytochemical composition of E. ulmoides bark infusions and tinctures and their dominant compounds using the HPLC-DAD-MS/MS method, and evaluated their anti-inflammatory effects in human immune cell models. The analysis identified lignans, iridoids, and caffeic acid derivatives as the dominant constituents of the tested samples. The extracts significantly inhibited the secretion of pro-inflammatory cytokines (TNF-α, IL-6, IL-8, MCP-1) in neutrophils, PBMC-derived monocytes/macrophages, and THP-1 cells. The results presented herein offer significant insights into the detailed phytochemical composition of E. ulmoides bark, and contribute to a deeper understanding of its anti-inflammatory mechanisms in human immune cells.

Eucommia folium can be Prepared as a Tea with the Ability to Prevent and Treat Hyperuricaemia

The aim of this study was to investigate the antihyperuricaemic (HUA) effect of Eucommia folium after preparing a tea made from its leaves (abbreviated as DZ) which has the ability to prevent and treat HUA. In this study, a mouse HUA model was established via gavage of potassium oxonate and hypoxanthine, and this HUA model was treated with DZ to investigate the therapeutic effect of DZ on HUA. This study recruited 30 HUA volunteers, who drank 10 g of DZ daily for four consecutive weeks. The serum HUA levels of UA volunteers were measured once per week to observe the anti-HUA efficacy of DZ at the clinical level. Animal experiments have shown that DZ has therapeutic effects on HUA. DZ effectively reduces the levels of uric acid (UA), creatinine (Cr), and urea nitrogen (BUN) in the serum of HUA mice; decreases xanthine oxidase (XOD) activity in the serum; and alleviates damage to kidney tissues and glomeruli. Metabolomic analysis revealed that DZ affects multiple metabolites, such as orotidine, orotic acid, ureidosuccinic acid, 1-methylhistidine, and other metabolites, and these metabolites are involved mainly in pyrimidine metabolism, histidine metabolism, and riboflavin metabolism. Clinical research revealed that, after DZ was consumed, the UA levels in the HUA volunteers significantly decreased. Our research findings suggest that DZ may have a protective effect against HUA. and is in the same class of traditional Chinese medicines used in medicine and food, with extremely low toxicity and high safety. Therefore, DZ may be suitable for preparation as a functional food with anti HUA effects. CLINICAL TRIAL NUMBER: Not applicable.

Total flavonoids isolated from Eucommia ulmoides can alleviate bone loss and regulate intestinal microbiota in ovariectomized rats

Ethnopharmacological relevance

Eucommia ulmoides, recognized as a traditional Chinese medicinal herb, can tonify liver and kidney and strengthen bones and muscles. Modern pharmacological research has proved that E. ulmoides could prohibit the occurrence of osteoporosis and arthritis.

Aim

To investigate the effect and action mechanism of total flavonoids isolated from the leaves of E. ulmoides (TFEL) on bone loss in ovariectomized (OVX) rats, and to study its effect on intestinal flora.

Materials and methods

The 3-month-old female rats were randomly divided into six groups: sham operation group, OVX model group, estradiol group, TFEL low (TFEL-L) (50), mid (-M) (100) and high (-H) (200 mg/kg/d) dose groups. After 13 weeks of treatment, the rats were sacrificed to measure bone turnover markers, related tissue biochemical indices, microstructure parameters, and osteoclastogenesis promotor RANKL and inhibitor OPG expression levels. Additionally, fecal samples were obtained for high-throughput sequencing to analyze the intestinal flora.

Results

Oral administration of TFEL for 13 weeks increased the serum level of bone formation marker PINP and decreased the level of bone resorption marker NTX-I. The femoral microstructure parameters of the TFEL-M and TFEL-H groups were significantly improved compared with the OVX group, which were also confirmed by H&E histological staining. High-throughput sequencing indicated that TFEL may regulate the composition of intestinal flora and intestinal microecology.

Conclusion

TFEL can prevent osteoporosis in OVX rats and has no toxic side effects. Meanwhile, TFEL can increase the diversity and improve the composition of intestinal flora in OVX rats.

Integrated proteomic and metabolomic analysis reveals the potential therapeutic mechanism of Quanduzhong capsule in rats with spontaneous hypertension and knee osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Quanduzhong capsule (QDZ), derived from Eucommia ulmoides Oliv., has been traditionally used in Chinese medicine for its beneficial effects on musculoskeletal health. Its clinical application has extended to conditions such as spontaneous hypertension combined with knee osteoarthritis (SKOA). However, the specific mechanisms by which QDZ alleviates symptoms and improves outcomes in this complex condition remain to be fully elucidated.

AIM OF THE STUDY

This study aims to evaluate the therapeutic potential of QDZ in treating SKOA. By performing serum proteomics and metabolomics, we seek to explore the related biological pathways and elucidate the mechanisms underlying QDZ's effects on SKOA.

MATERIALS AND METHODS

Serum samples from control, spontaneous hypertension (SHR), SKOA, and SKOA treated with QDZ groups were analyzed using data-independent acquisition-based proteomics to identify differentially expressed proteins. Serum levels of angiotensin II, norepinephrine, endothelin-1, classical pro-inflammatory factors such as macrophage colony-stimulating factor, tumor necrosis factor-alpha, and interleukin-1 beta were measured. Additionally, serum metabolomics was performed to examine the changes in metabolite profiles. Correlation analysis was conducted to link changed proteins and metabolites with key pathways affected by QDZ.

RESULTS

Proteomics analysis revealed significant alterations in serum protein expression between control, SHR, and SKOA groups, with changes in pathways related to immune regulation and vascular function. KEGG enrichment analysis highlighted pathways such as endocytosis, synaptic vesicle cycling, and immune responses were enriched in SKOA group compared with control group. QDZ treatment significantly modulated above pathways and reduced inflammatory and cardiovascular markers which were upregulated in SKOA group. Metabolomics analysis showed that QDZ reversed SKOA-induced changes in amino acid and organic acid metabolism, affecting pathways including valine, leucine, and isoleucine metabolism, as well as the TCA cycle. Correlation analysis revealed significant relationships between key proteins and metabolites, underscoring the integrated role of immune and metabolic pathways in QDZ's effects.

CONCLUSIONS

Our results indicate QDZ has a significant therapeutic potential for SKOA by modulating both protein and metabolite profiles associated with inflammation, vascular dysfunction, and metabolic imbalance. Our findings provide insights into the mechanisms through which QDZ exerts its effects and support its use as a promising treatment for SKOA. This study highlights the impact of QDZ on proteomic and metabolomic alterations, offering a basis for its broader application in treating SKOA.

Toxic effects and safety assessment of Xanthoceras sorbifolium bunge seed kernels

ETHNOPHARMACOLOGICAL RELEVANCE

Xanthoceras sorbifolium Bunge (X. sorbifolia), an oil crop native to northern China, is valued for both its edible and medicinal uses. It has various applications, including the production of edible and bioactive oils, and is used in traditional medicine for its antioxidant and anti-inflammatory properties. However, the toxicity of X. sorbifolia, particularly its widely used seed kernels, remains unclear.

AIM OF THE STUDY

This study aimed to evaluate the acute toxicity and safety risks of X. sorbifolia seed kernels based on human-recommended doses by in vitro or in vivo experiments, and integrating network analysis.

MATERIALS AND METHODS

In this study, rats and mice were employed as model organisms to investigate the acute toxicity of X. sorbifolia seed kernels. The experiments included the Salmonella typhimurium reverse mutation test, red blood cell micronucleus test, spermatocyte chromosome aberration test in mice, and a 90-day exposure study in rats to assess the potential toxicity and safety risks of the seed kernels. Based on this, combined with The Comparative Toxicogenomics Database (CTD), the biological functions of the main active ingredients of X. sorbifolia were further explored through integrated network analysis, and the anti-inflammatory effect of X. sorbifolia was explored through cotton ball granuloma inflammation experiment.

RESULTS

During the experimental period, animals in all treatment groups demonstrated normal growth and development. Although some detection indicators showed significant differences in different treatment groups, the results were still within a reasonable range. In addition, by screening the CTD, 120 target genes with potential interactions of the main active ingredients in the kernel of X. sorbifolia were obtained for analysis, and it was found that these genes were involved in important biological processes such as response to oxidative stress, response to reactive oxygen species, and regulation of inflammatory response. The cotton ball granuloma inflammation experiment in rats also suggested that X. sorbifolia tended to inhibit the proliferation of granulomas, indicating that the kernel of X. sorbifolia has potential anti-inflammatory and antioxidant properties.

CONCLUSION

The findings suggested that X. sorbifolia seed kernels were safe within the recommended dosage range. As a traditional Chinese medicine prescription, it has certain anti-inflammatory and antioxidant effects. This study provides valuable reference guidelines for the clinical application of X. sorbifolia seed kernels and encourages further research into its potential uses and safety.

Leveraging AI technology for distinguishing Eucommiae Cortex processing levels and evaluating anti-fatigue potential

Eucommiae Cortex (ECO) is a traditional medicinal and edible plant endemic to China, highly prized for its numerous health benefits. It typically undergoes special processing before application. The efficacy of ECO is influenced by processing techniques, necessitating the assurance of stability and consistency in its effects. However, existing methods for identifying ECO are cumbersome, thus, there is an urgent need to develop an accurate, rapid, and non-invasive assessment method. Deep learning techniques employing ResNet and Vision Transformer (ViT) models were employed to classify ECO images at various processing levels. Concurrently, the anti-fatigue properties of ECO were assessed through swimming time, pole climbing experiments, and biochemical analyses including SDH, LDH, ATP content, Na+-K+-ATPase, and Ca2+-Mg2+-ATPase indices. We demonstrated the efficacy of using image analysis to automatically classify ECO with a high degree of accuracy. The results indicated that the Vision Transformer model performed exceptionally well, achieving an accuracy rate exceeding 95 % in grading ECO images. Additionally, our study revealed that mice treated with moderately processed ECO displayed enhanced fatigue mitigation compared to other processing levels, as evidenced by multiple assessments.

Exogenous application of Eucommia ulmoides β-1, 4-glucanase promotes propagation by increasing the expression of wound healing genes

Eucommia ulmoides (E. ulmoides) is a valuable gum-producing plant and traditional Chinese medicine. The utilization value of E. ulmoides varies according to the sex of the plant, and due to its perennial characteristics, the identification of male and female is challenging. To meet production demands, gender selection through grafting has been employed. The fusion of rootstock and scion cells in grafted plants can be enhanced by β-1, 4-glucanase, thus improving the grafting survival rate. However, extracting β-1, 4-glucanase in vivo poses difficulties. In this study, the β-1, 4-glucanase gene of E. ulmoides was cloned, and the total length of the gene was 1917 bp, encoding 638 amino acids. Pichia pastoris engineering bacteria were used to express β-1, 4-glucanase. The optimal fermentation conditions included a pH of 6, a temperature of 28 ℃, a methanol content of 1.5%, and a fermentation period of 96 hours. After purification, the enzyme activity of the target protein was measured to be 286.35 U/mL. Protein concentrations of 5 mg/mL, 10 mg/mL, and 15 mg/mL were tested for E. ulmoides grafting. The results showed that the protein could promote wound healing and improve the survival rate of E. ulmoides grafting. In conclusion, this study successfully developed an enzyme that improves the survival rate of E. ulmoides grafting, and provides valuable insights for the breeding of male and female E. ulmoides grafts.

Non-targeted metabolomics and explainable artificial intelligence: Effects of processing and color on coniferyl aldehyde levels in Eucommiae cortex

Eucommia ulmoides, a plant native to China, is valued for its medicinal properties and has applications in food, health products, and traditional Chinese medicine. Processed Eucommiae Cortex (EC) has historically been a highly valued medicine. Ancient doctors had ample experience processing EC, especially with ginger juice, as documented in traditional Chinese medical texts. The combination of EC and ginger juice helps release and transform the active ingredients, strengthening the medicine's effectiveness and improving its taste and shelf life. However, the lack of quality control standards for Ginger-Eucommiae Cortex (G-EC), processed from EC and ginger, presents challenges for its industrial and clinical use. This study optimized G-EC processing using the CRITIC and Box-Behnken methods. Metabolomics showed 517 chemical changes between raw and processed G-EC, particularly an increase in coniferyl aldehyde (CFA). Explainable artificial intelligence techniques revealed the feasibility of using color to CFA content, providing insights into quality indicators.

Nutraceuticals as Modulators of Molecular Placental Pathways: Their Potential to Prevent and Support the Treatment of Preeclampsia

Preeclampsia (PE) is a serious condition characterized by new-onset hypertension and proteinuria or organ dysfunction after the 20th week of gestation, making it a leading cause of maternal and fetal mortality worldwide. Despite extensive research, significant gaps remain in understanding the mechanisms underlying PE, contributing to the ineffectiveness of current prevention and treatment strategies. Consequently, premature cesarean sections often become the primary intervention to safeguard maternal and fetal health. Emerging evidence indicates that placental insufficiency, driven by molecular disturbances, plays a central role in the development of PE. Additionally, the maternal microbiome may be implicated in the pathomechanism of preeclampsia by secreting metabolites that influence maternal inflammation and oxidative stress, thereby affecting placental health. Given the limitations of pharmaceuticals during pregnancy due to potential risks to fetal development and concerns about teratogenic effects, nutraceuticals may provide safer alternatives. Nutraceuticals are food products or dietary supplements that offer health benefits beyond basic nutrition, including plant extracts or probiotics. Their historical use in traditional medicine has provided valuable insights into their safety and efficacy, including for pregnant women. This review will examine how the adoption of nutraceuticals can enhance dysregulated placental pathways, potentially offering benefits in the prevention and treatment of preeclampsia.

Community assembly and potential function analysis of the endophyte in Eucommia ulmoides

Endophytes play a pivotal role in protecting host plants from both biotic and abiotic stresses, promoting the production of active components (AC) and plant growth. However, the succession of the endophyte community in Eucommia ulmoides (E. ulmoides), particularly the community assembly and function, has not been extensively investigated. In this study, we employed high-throughput sequencing and bioinformatics tools to analyze endophyte diversity across different tree ages, parts, and periods. We examined the population differences, correlations, community assembly mechanisms, and functional roles of these endophytes. Functional predictions via PICRUSt2 revealed that most endophytic fungal functions were linked to biosynthesis, with significant differences in biosynthetic functional abundance across parts and periods. In contrast, the metabolic activity of endophytic bacteria remained stable across different periods and parts. Correlation analysis further confirmed a strong positive relationship between ACs and certain endophytic fungi. Among them, the fungal phyla Ascomycota and Basidiomycota were identified as key contributors to the metabolism of chlorogenic acid (CA), while Aucubin was significantly positively correlated with several endophytic bacteria. These findings provide valuable insights into the functional roles and community assembly mechanism of E. ulmoides endophytes, as well as their symbiotic relationships.

The role of Chinese herbal medicine in the regulation of oxidative stress in treating hypertension: from therapeutics to mechanisms

BACKGROUND

Although the pathogenesis of essential hypertension is not clear, a large number of studies have shown that oxidative stress plays an important role in the occurrence and development of hypertension and target organ damage.

PURPOSE

This paper systematically summarizes the relationship between oxidative stress and hypertension, and explores the potential mechanisms of Chinese herbal medicine (CHM) in the regulation of oxidative stress in hypertension, aiming to establish a scientific basis for the treatment of hypertension with CHM.

METHODS

To review the efficacy and mechanism by which CHM treat hypertension through targeting oxidative stress, data were searched from PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, the Chinese National Knowledge Infrastructure, the VIP Information Database, the Chinese Biomedical Literature Database, and the Wanfang Database from their inception up to January 2024. NPs were classified and summarized by their mechanisms of action.

RESULTS

In hypertension, the oxidative stress pathway of the body is abnormally activated, and the antioxidant system is inhibited, leading to the imbalance between the oxidative and antioxidative capacity. Meanwhile, excessive production of reactive oxygen species can lead to endothelial damage and vascular dysfunction, resulting in inflammation and immune response, thereby promoting the development of hypertension and damaging the heart, brain, kidneys, blood vessels, and other target organs. Numerous studies suggested that inhibiting oxidative stress may be the potential therapeutic target for hypertension. In recent years, the clinical advantages of traditional Chinese medicine (TCM) in the treatment of hypertension have gradually attracted attention. TCM, including active ingredients of CHM, single Chinese herb, TCM classic formula and traditional Chinese patent medicine, can not only reduce blood pressure, improve clinical symptoms, but also improve oxidative stress, thus extensively affect vascular endothelium, renin-angiotensin-aldosterone system, sympathetic nervous system, target organ damage, as well as insulin resistance, hyperlipidemia, hyperhomocysteinemia and other pathological mechanisms and hypertension related risk factors.

CONCLUSIONS

CHM display a beneficial multi-target, multi-component, overall and comprehensive regulation characteristics, and have potential value for clinical application in the treatment of hypertension by regulating the level of oxidative stress.

Extraction, Characterization, and Antioxidant Activity of Eucommia ulmoides Polysaccharides

Herein, the ultrasound-assisted extraction conditions affecting the yield of EUPS (Eucommia ulmoides polysaccharide) were analyzed using a Box-Behnken response surface design. The alleviation effect of EUPS on diquat-induced oxidative stress in mice was also studied. A maximum EUPS yield of 2.60% was obtained under the following optimized conditions: an extraction temperature of 63 °C, extraction time of 1 h, and ratio of liquid to raw materials of 22:1. EUPS exhibited strong 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging ability (87.05%), 2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical-scavenging ability (101.17%), and hydroxyl radical-scavenging ability (62.92%). The administration of EUPS increased the activities of superoxide dismutase, catalase, and glutathione peroxidase and decreased malondialdehyde levels in the livers of mice exposed to diquat. EUPS may inhibit the downregulation of NAD(P)H:quinoneoxidoreductase 1 and heme oxygenase 1 mRNA expression in the livers of diquat-administered mice through the Nrf2-Keap1 signaling pathway. Moreover, the abundance of Firmicutes and Ligilactobacillus was enhanced, whereas that of Helicobacter decreased in the gut of the remaining groups of mice compared with that of the diquat-treated mice. Therefore, EUPS exhibited an antioxidant effect and improved oxidative stress and intestinal flora abundance in mice.

Efficient plant regeneration through direct shoot organogenesis and two-step rooting in Eucommia ulmoides Oliver

Eucommia ulmoides Oliver (E. ulmoides Oliver), a multipurpose woody plant, holds great economic significance due to its expansive medicinal, food and industrial applications. The rapid advancement of E. ulmoides in various fields has resulted in the inadequacy of existing breeding methods to meet its growth and annual production demands. Consequently, there is an urgent need for innovative propagation strategies. This study introduces an optimized micropropagation protocol for E. ulmoides, facilitating direct shoot organogenesis from nodal segments with axillary buds. We systematically examined the impact of basal medium composition, plant growth regulators, photosynthetic photon flux density, and sucrose concentration on bud sprouting. Employing cuttings with axillary buds as propagation material, we achieved a shortened cultivation period of merely 4 weeks for bud elongation and proliferation, marking a substantial enhancement in propagation efficiency. Notably, the Driver Kuniyuki Walnut medium, supplemented with 20.0 g L-1 sucrose and 2.0 mg L-1 trans-zeatin, induced shoots sprouting with a 100% success rate and an average length of 5.18 cm per nodal segment, equating to a great bud propagation rate of approximately 500%. Furthermore, a light source with an intensity of 80 μmol m-2 s-1 was shown the most economical choice. To address the primary challenge of inducing roots in regenerated plants, we employed a refined two-step rooting technique. This method yielded the optimal rooting frequency of 93.02%, producing an average of 5.90 adventitious roots per plantlet, each with an average length of 2.77 cm. The micropropagation program developed in this work will be the cornerstone for the preservation of the germplasm of E. ulmoides and its long-term use in medicinal and industrial applications.

Advances in Eucommia ulmoides polysaccharides: extraction, purification, structure, bioactivities and applications

Eucommia ulmoides (EU) is a precious tree species native to China originating during the ice age. This species has important economic value and comprehensive development potential, particularly in medicinal applications. The medicinal parts of EU are its bark (Eucommiae cortex) and leaves (Eucommiae folium) which have been successively used as a traditional Chinese medicine to treat diseases since the first century BC. During the last 2 decades, as natural polysaccharides have become of increasing interest in pharmacology, biomedicine, cosmetic and food applications, more and more scholars have begun to study polysaccharides derived from EU as well. EU polysaccharides have been found to have a variety of biological functions both in vivo and in vitro, including immunomodulatory, antioxidant, anti-inflammatory, anticomplementary, antifatigue, and hepatoprotective activities. This review aims to summarize these recent advances in extraction, purification, structural characteristics, pharmacological activities and applications in different fields of EU bark and leaf polysaccharides. It was found that both Eucommiae folium polysaccharides and Eucommiae cortex polysaccharides were suitable for medicinal use. Eucommiae folium may potentially be used to substitute for Eucommiae cortex in terms of immunomodulation and antioxidant activities. This study serves as a valuable reference for improving the comprehensive utilization of EU polysaccharides and further promoting the application of EU polysaccharides.

Cloning and functional characterization of the legumin A gene (EuLEGA) from Eucommia ulmoides Oliver

Legumin A is a seed storage protein that provides nutrients for seed germination. The purpose of this study was to describe the structure and expression pattern of the EuLEGA gene in Eucommia ulmoides Oliver (E. ulmoides) and to infer its functional role. The 1287 bp coding sequence of the EuLEGA CDS of the EuLEGA gene, encoding a protein containing 428 amino acid residues, was cloned. The structure predicted that the protein belonged to the RmlC (deoxythymidine diphosphates, dTDP)-4-dehydrorhamnose 3,5-epimerase)-like cupin conserved domain family, which contains both RmlC, a key enzyme for the synthesis of rhamnose and legumin A. The overexpression (OE) vector of the EuLEGA gene was constructed and genetically transformed into tobacco and E. ulmoides; the RNA interference (RNAi) vector of the EuLEGA gene was constructed and genetically transformed into E. ulmoides; and the contents of legumin A and rhamnose were detected. The results showed that the EuLEGA gene could significantly increase the content of legumin A in transgenic tobacco leaves and transgenic E. ulmoides regenerative buds, and the OE of this gene in E. ulmoides could promote an increase in rhamnose content. RNAi caused a significant decrease in the legumin A content in the regenerated buds of E. ulmoides. These was a significant increase in legumin A in the transgenic tobacco seeds, and these results indicate that the expression of the EuLEGA gene is closely related to the accumulation of legumin A. Subcellular localization studies revealed that EuLEGA is localized to the cytoplasm with the vacuolar membrane. Analysis of the EuLEGA gene expression data revealed that the expression level of the EuLEGA gene in the samaras was significantly greater than that in the leaves and stems. In addition, the study also demonstrated that GA3 can upregulate the expression levels of the EuLEGA gene, while ABA and MeJA can downregulate its expression levels.