Multi-level fingerprinting and immune activity evaluation for polysaccharides from Dioscorea opposita Thunb.

To establish the quality control method of Dioscorea opposita Thunb., the multi-level fingerprinting of polysaccharides was established and the relationship between fingerprint and immune activity was analyzed. The two molecular weight segments Mw1 (1.38 × 105-1.63 × 106 Da) and Mw2 (3.27 × 103-4.37 × 103 Da), thirteen infrared absorption peaks (3399.26 cm-1, 2929.32 cm-1, 1631.78 cm-1, 1400.39 cm-1, 1351.80 cm-1, 1123.58 cm-1, 1024.76 cm-1, 931.53 cm-1, 854.76 cm-1, 760.43 cm-1, 708.14 cm-1, 616.47 cm-1, and 526.78 cm-1), and four monosaccharides (Man, Rha, GalA, and Glc) were used to evaluate the quality of Dioscorea opposita Thunb. The molecular weight fragments of Mw1, FT-IR absorption peaks of 1631.78 cm-1, and two monosaccharides (Man and Glc) would be used to identify Dioscorea opposita Thunb. polysaccharide (DOP) from different origins. The relationship of spectrum-effect showed that polysaccharides with features such as higher Mw1, a lower peak height of 1631.78 cm-1, higher content of Man, and lower content of Glc exerted stronger immune activity. In conclusion, this study established a polysaccharide-based quality evaluation method for Dioscorea opposita Thunb. and explored the relationship between polysaccharide fingerprints and in vitro immune activity, which provided a basis for further research on Dioscorea opposita Thunb.

A Frontier Review of Nutraceutical Chinese Yam.

Yams are the edible subterranean rhizomes, or tubers, of plants from the genus Dioscorea. There are approximately 600 species of yam plants in the world, with more than 90 of these growing in East Asia. One particular species, Dioscorea opposita Thunb., is highly praised as "the Chinese yam". This distinction arises from millennia of storied history, both as a nutritional food source and as a principal ingredient in traditional Chinese medicine. Among the many cultivars of Dioscorea opposita Thunb., Huai Shanyao has been widely regarded as the best. This review surveyed the historical background, physiochemical composition, applications as food and medicine, and research prospects for the Chinese yam. Modern science is finally beginning to confirm the remarkable health benefits of this yam plant, long-known to the Chinese people. Chinese yam promises anti-diabetic, anti-oxidative, anti-inflammatory, immunomodulatory, anti-hyperlipidemic, anti-hypertensive, anti-cancer, and combination treatment applications, both as a functional food and as medicine.

Molecular Insights into the Defense of Dioscorea opposita Cultivar Tiegun Callus Against Pathogenic and Endophytic Fungal Infection Through Transcriptome Analysis.

Dioscorea opposita cultivar Tiegun is an economically important crop with high nutritional and medicinal value. Plants can activate complex and diverse defense mechanisms after infection by pathogenic fungi. Moreover, endophytic fungi can also trigger the plant immune system to resist pathogen invasion. However, the study of the effects of endophytic fungi on plant infection lags far behind that of pathogenic fungi, and the underlying mechanism is not fully understood. Here, the black spot pathogen Alternaria alternata and the endophytic fungus Penicillium halotolerans of Tiegun were identified and used to infect calli. The results showed that A. alternata could cause more severe membrane lipid peroxidation, whereas P. halotolerans could rapidly increase the activity of the plant antioxidant enzymes superoxide dismutase, peroxidase, and catalase; thus, the degree of damage to the callus caused by P. halotolerans was weaker than that caused by A. alternata. RNA sequencing analysis revealed that various plant defense pathways, such as phenylpropanoid biosynthesis, flavonoid biosynthesis, plant hormone signal transduction, and the mitogen-activated protein kinase signaling pathway, play important roles in triggering the plant immune response during fungal infection. Furthermore, the tryptophan metabolism, betalain biosynthesis, fatty acid degradation, flavonoid biosynthesis, tyrosine metabolism, and isoquinoline alkaloid biosynthesis pathways may accelerate the infection of pathogenic fungi, and the ribosome biogenesis pathway in eukaryotes may retard the damage caused by endophytic fungi. This study lays a foundation for exploring the infection mechanism of yam pathogens and endophytic fungi and provides insight for effective fungal disease control in agriculture.

Identification of WRKY gene family in Dioscorea opposita Thunb. reveals that DoWRKY71 enhanced the tolerance to cold and ABA stress.

WRKY transcription factors constitute one of the largest plant-specific gene families, regulating various aspects of plant growth, development, physiological processes, and responses to abiotic stresses. This study aimed to comprehensively analyze the WRKY gene family of yam (Dioscorea opposita Thunb.), to understand their expression patterns during the growth and development process and their response to different treatments of yam and analyze the function of DoWRKY71 in detail. A total of 25 DoWRKY genes were identified from the transcriptome of yam, which were divided into six clades (I, IIa, IIc, IId, IIe, III) based on phylogenetic analysis. The analysis of conserved motifs revealed 10 motifs, varying in length from 16 to 50 amino acids. Based on real-time quantitative PCR (qRT-PCR) analysis, DoWRKY genes were expressed at different stages of growth and development and responded differentially to various abiotic stresses. The expression level of DoWRKY71 genes was up-regulated in the early stage and then down-regulated in tuber enlargement. This gene showed responsiveness to cold and abiotic stresses, such as abscisic acid (ABA) and methyl jasmonate (MeJA). Therefore, further study was conducted on this gene. Subcellular localization analysis revealed that the DoWRKY71 protein was localized in the nucleus. Moreover, the overexpression of DoWRKY71 enhanced the cold tolerance of transgenic tobacco and promoted ABA mediated stomatal closure. This study presents the first systematic analysis of the WRKY gene family in yam, offering new insights for studying WRKY transcription factors in yam. The functional study of DoWRKY71 lays theoretical foundation for further exploring the regulatory function of the DoWRKY71 gene in the growth and development related signaling pathway of yam.

Structural characterization and immunomodulatory activity of a polysaccharide from Dioscotea opposita.

The purified polysaccharides fraction, DOP-2, was prepared from Dioscorea opposita Thunb (D. opposita). This study combined in vitro and in vivo experiments to comprehensively investigate the index changes in RAW264.7 cells and immunocompromised mice under DOP-2 intervention, aiming to elucidate the potential mechanisms of immunomodulatory effects of DOP-2. DOP-2 (10 âˆ¼ 500 µg/mL) significantly elevated the levels of NO, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) factors secreted by RAW264.7 cells, and restored the body weight of immunosuppressed mice and improve the degree of injury to the immune organ index, resulting in significant immunomodulatory effects. Notably, DOP-2 promoted the production of short-chain fatty acids (SCFAs) in immunosuppressed mice and modulated the composition of their gut microflora. These findings highlight the potential benefits of DOP-2 therapy in improving immune function and gut health, and will provide a theoretical basis for the application of D. opposita polysaccharides as an immunomodulatory adjuvant.

Unveiling the impact of harvest time on Dioscorea opposita Thunb. cv. Tiegun maturity by NMR-based metabolomics and LC-MS/MS analysis.

BACKGROUND: Dioscorea opposita Thunb. cv. Tiegun maturity (DM) is an important factor influencing its quality. However, there are few studies on the impact of harvest time on its maturation. In the present study, a NMR-based metabolomics approach was applied to investigate the dynamic metabolic changes of D. opposita Thunb. cv. Tiegun at six different harvest stages: stage 1 (S1), stage 2 (S2), Stage 3 (S3), stage 4 (S4), stage 5 (S5) and stage 6 (S6). RESULTS: Principal component analysis showed distinct segregation of samples obtained from S1, S2 and S3 compared to those derived from S4, S5 and S6. Interestingly, these samples from the two periods were obtained before and after frost, indicating that frost descent might be important for DM. Eight differential metabolites responsible for good separation of different groups were identified by the principal component analysis loading plot and partial least squares-discriminant analysis. In addition, quantitative analysis of these metabolites using liquid chromatography-tandem mass spectrometry determined the effects of harvest time on these metabolite contents, two of which, sucrose and allantoin, were considered as potential biomarkers to determine DM. CONCLUSION: The present study demonstrated that NMR-based metabolomics approach could serve as a powerful tool to identify differential metabolites during harvesting processes, also offering a fresh insight into understanding the DM and the potential mechanism of quality formation. © 2024 Society of Chemical Industry.

Comprehensive widely targeted metabolomics to decipher the molecular mechanisms of Dioscorea opposita thunb. cv. Tiegun quality formation during harvest.

Dioscorea opposita Thumb. cv. Tiegun is commonly consumed as both food and traditional Chinese medicine, which has a history of more than two thousand years. Harvest time directly affects its quality, but few studies have focused on metabolic changes during the harvesting process. Here, a comprehensive metabolomics approach was performed to determine the metabolic profiles during six harvest stages. Thirty eight metabolites with significant differences were determined as crucial participants. Related metabolic pathways including phenylalanine, tyrosine and tryptophan biosynthesis, stilbenoid, diarylheptanoid and gingerol biosynthesis, phenylpropanoid biosynthesis, flavonoid biosynthesis and tryptophan metabolism were the most active pathways during harvest. The results revealed that temperature has a significant impact on quality formation, which suggested that Dioscorea opposita thumb. cv. Tiegun harvested after frost had higher potential value of traditional Chinese medicine. This finding not only offered valuable guidance for yam production, but also provided essential information for assessing its quality.

Anti-obesity effects exerted by Dioscorea opposita Thunb. polysaccharides in diet-induced obese mice.

Obesity is characterized by chronic inflammation, insulin resistance, and gut microbiota dysbiosis. Dioscorea opposita Thunb. is a traditional food and medicine homolog from China. In the present study, polysaccharides isolated from a water extract of Dioscorea opposita Thunb. (DOTPs) were prepared. We showed that DOTPs reduced body weight, accumulation of fat tissues, insulin resistance, and inflammation in high-fat diet (HFD)-fed mice. Further experiments showed that DOTPs could regulate the composition of the gut microbiota in HFD mice. DOTPs supplementation in HFD-fed mice resulted in the reduction of the Firmicutes-to-Bacteroidetes ratio. We further demonstrated that DOTPs supplementation enhanced bacterial levels of Akkermansia and reduced levels of Ruminiclostridium_9. A significant reduction of glycolysis metabolism related to obesity and gut microbiota dysbiosis was also observed upon administration of DOTPs. Our results suggest that DOTPs can produce significant anti-obesity effects, by inhibiting systematic inflammation and ameliorating gut microbiota dysbiosis in diet-induced obese mice.

Dioscoreae Rhizoma starch improves chronic diarrhea by regulating the gut microbiotas and fecal metabolome in rats.

Chinese yam (Dioscorea opposite Thunb.) has been used as food and medicine to treat diarrhea for thousands of years. This article aimed to elucidate the potential mechanism of Dioscoreae Rhizoma starch in alleviating chronic diarrhea induced by rhubarb based on gut microbiotas and fecal metabolome. The administration of the Dioscoreae Rhizoma aqueous extracts, crude polysaccharides, and starch could improve diarrhea and alleviate intestinal injury in chronic diarrhea rats. The Dioscoreae Rhizoma starch displayed the most apparent effect on regulating intestinal microbiotas by increasing the abundance and diversity of microbiotas. At the genus level, there were 17 changed intestinal microbiotas in model rats, and the treatment with Dioscoreae Rhizoma starch regulated 11 microbiotas. Metabolomics analysis revealed that Dioscoreae Rhizoma starch could regulate abnormal fecal metabolites to alleviate diarrhea, and these metabolites are involved in phenylalanine, tyrosine, and tryptophan biosynthesis; tyrosine metabolism; vitamin B6 metabolism; and purine metabolism. This study will contribute to the further research and development of Dioscoreae Rhizoma starch.

Astragulus embranaceus (Fisch.) Bge-Dioscorea opposita Thunb herb pair ameliorates sarcopenia in senile type 2 diabetes mellitus through Rab5a/mTOR-mediated mitochondrial dysfunction.

ETHNOPHARMACOLOGICAL RELEVANCE: The combination of Astragulus embranaceus (Fisch.) Bge (Huangqi) and Dioscorea opposita Thunb (Shanyao) are one of the most widely accepted herb pairs in traditional Chinese medicine prescriptions for treating sarcopenia. However, the mechanisms underlying the combination of these herbs for anti-sarcopenia treatment are not yet fully understood. AIM OF THE STUDY: To investigate the potential effect of the Astragulus embranaceus (Fisch.) Bge and Dioscorea opposita Thunb herb pair (Ast-Dio) on sarcopenia in mice that have been induced with senile type 2 diabetes mellitus, as well as to explore the underlying mechanisms related to the Rab5a/mTOR signaling pathway and mitochondrial quality control. MATERIALS AND METHODS: Network pharmacology was utilized to identify the main active ingredients of Ast-Dio and potential therapeutic targets for sarcopenia. Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were conducted to explore the underlying mechanisms of Ast-Dio in treating sarcopenia. The high-performance liquid chromatography method coupled with triple-quadrupole tandem mass spectrometry was developed to quantify the major constituents of Ast-Dio. Male C57/BL6 mice, aged 12 months, induced with type 2 diabetes mellitus via streptozotocin were divided into three groups for 8 weeks: the model group, Ast-Dio treatment group (7.8 g/kg), and metformin treatment group (100 mg/kg). Normal control groups included mice aged 3 and 12 months, respectively. The study monitored changes in fasting blood glucose levels, grip strength, and body weight during 8 weeks of intragastric administration. Liver and kidney function in mice was evaluated by measuring the levels of serum creatinine, alanine transaminase, and aspartate transaminase. Skeletal muscle mass condition was evaluated by muscle weight, and hematoxylin and eosin staining. Protein and mRNA expressions related to muscle atrophy, mitochondrial quality control, and the Rab5a/mTOR signaling pathway were detected using immunofluorescence staining, immunohistochemical staining, Western blotting, and quantitative real-time polymerase chain reaction. In addition, transmission electron microscopy was employed to investigate the condition of mitochondria in the groups. RESULTS: Through the prediction analysis of network pharmacology, we identified mTOR as one of the primary targets for Ast-Dio therapy of sarcopenia. Gene Ontology functional enrichment analysis revealed that mitochondrial control quality is crucial in the treatment of sarcopenia with Ast-Dio. Our findings showed that senile type 2 diabetes mellitus induced muscle mass loss and a reduction in grip strength, both of which were dramatically restored by Ast-Dio treatment. Notably, Ast-Dio increased Myogenin expression while decreasing Atrogin-1 and MuRF-1 expression. Additionally, Ast-Dio activated Rab5a/mTOR and its downstream effector AMPK. Moreover, Ast-Dio modulated mitochondrial quality control by decreasing Mitofusin-2 expression while increasing the expression of TFAM, PGC-1α, and MFF. CONCLUSIONS: Our results suggest that Ast-Dio treatment may alleviate sarcopenia in mice with senile type 2 diabetes mellitus through its effects on the Rab5a/mTOR pathway and mitochondrial quality control.

A sesquiterpene isolated from the stems and leaves of Dioscorea opposita thunb. Transforms the composition of immune cells through ERß in a mouse model of LPS-induced lung injury.

Acute lung injury (ALI) is a common critical disease with a high mortality rate. Natural products have marked efficacy in the prevention and treatment of ALI, in addition, estrogen and its receptors are involved in the pathogenesis and development of lung injury. Our previous research shows that sesquiterpenes isolated from the stems and leaves of Dioscorea opposita Thunb. have anti-inflammatory and estrogenic-like activity. In the present study, sesquiterpene (A1) is a natural extract from the stems and leaves of Dioscorea opposita Thunb. with a view to determining whether A1 can improve lung function in a mouse model of LPS-induced ALI and exploring the involvement of the estrogen receptor ß (ERß) pathway. A1 (20 or 40 mg/kg, i. g., 2 times/day) was administered for 3 d, followed by the induction of ALI via an intratracheal LPS drip (5 mg/kg/2 h). The lung function and levels of inflammation, immune cells, apoptosis, and ERß expression were examined. The antagonistic activity of specific ERß blocker (THC, 1 µM) against A1 (20 µM) in co-cultured BEAS-2B cells and splenic lymphocytes induced with LPS (1 µg/mL, 24 h) was also investigated to assess whether the observed effects of A1 were mediated by ERß. A1 improved lung function, regulated the immune system, and decreased inflammation and apoptosis. Moreover, A1 increased the expression of ERß in LPS-induced mice, and antagonism of ERß decreased the protective effects of A1 in a co-culture system. A1 had anti-ALI effects that might partially mediated through ERß signaling. Our data provide molecular justification for the use of A1 in the treatment of ALI.

A Dioscorea opposita Thunb Polysaccharide-Based Dual-Responsive Hydrogel for Insulin Controlled Release.

A novel hydrogel (DOP/PEI-PBA) based on the "three-component" reaction of 2-formylphenylboric acid (2-FPBA), the primary amine group of polyethyleneimine (PEI) and the cis-o-dihydroxy groups of Dioscorea opposita Thunb polysaccharide (DOP) was designed in this work. The hydrogel can be easily prepared by simply mixing the three reactants at room temperature. The hydrogel had dual responsiveness to glucose and pH, and can realize the controllable release of insulin. Moreover, the hydrogel combining insulin and DOP can inhibit the reactive oxygen species (ROS) level and malondialdehyde (MDA) content, and promote glucose consumption as well as the level of superoxide dismutase (SOD), in high-glucose-induced injury in HL-7702 cells, which reflects the synergistic effect of insulin and DOP to protect hepatocytes from oxidative stress at the same time. Further in vitro cytotoxicity studies showed that the hydrogel had good biocompatibility and no obvious toxicity to cells. These indicate that the prepared hydrogel (DOP/PEI-PBA) can be expected to be applied in the clinical treatment of insulin deficiency in diabetes.

A galacturonan from Dioscorea opposita Thunb. regulates fecal and impairs IL-1 and IL-6 expression in diarrhea mice.

Antibiotic-associated diarrhea (AAD) is a common side-effect of antibiotic treatment resulting from an imbalance in the colonic bacteria. The hypothesis of this study is to ask whether polysaccharide from the rhizome of Dioscorea opposita which is recorded as conventional herbs and food for diarrhea treatment in Southeast Asia, may be an active compound against diarrhea induced by antibiotics. To address, firstly, a homogenous polysaccharide, DOP0.2-S-3 was characterized as a homogalacturonan containing linear repeating units of → 4)-α-D-GalAp(1 → 4)-α-D-GalAp(1 → with the average molecular weight of 14 kDa. DOP0.2-S-3 significantly reduced the water content and defecation times caused by AAD in mice, while it also remarkably attenuated the cytokines of IL-1ß and IL-6 expression in mice colon tissues. DOP0.2-S-3 decreased potential pathogen and increased Bacteroidetes in the mice gut. These results suggested DOP0.2-S-3 might be a new leading compound for the functional foods or drug candidate development against AAD partially through regulating gut flora.

Isolation and structure characterization of a low methyl-esterified pectin from the tuber of Dioscorea opposita Thunb.

A low methyl-esterified pectin (33.2% methyl-esterification degree) was isolated from the tuber of Dioscorea opposita Thunb., which was an edible and medicinal material in China. This pectin (Mw of 1.3 × 104 g/mol) contained the ~59.1% homogalacturonan (HG) and ~38.1% highly branched rhamnogalacturonan I (RG-I) region with possible side chains embracing arabinogalactan II, arabinan or arabinogalactan I. The fragments including HG backbone consisting of â†’ 4)-α-GalpA-(1 â†’ and â†’ 4)-α-GalpA-6-O-methyl-(1 â†’ with molar ratio of ~2:1, and repeating unit of arabinogalactan II side chain composed of α-Araf-(1 â†’ and â†’ 3,6)-ß-Galp-(1→, were speculated through methylation analysis and NMR spectra. However, the linkage pattern for RG-I backbone and side chains were indiscernible due to limited resolution of NMR spectra. Besides, the pectin adopted a flexible chain conformation in 0.1 M NaNO3 solution. These results provided a structural basis for study on polysaccharide from D. opposite, which was benefit for development of functional food of yam.

The cold-soaking extract of Chinese yam (Dioscorea opposita Thunb.) protects against erectile dysfunction by ameliorating testicular function in hydrocortisone-induced KDS-Yang rats and in oxidatively damaged TM3 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Clinical applications and pharmacological research suggest that Dioscorea opposita Thunb. (Chinese yam), a well-known traditional Chinese medicine which has been used for more than 2000 years to nourish kidney-yang and protect the male reproductive system, might be efficacious for the treatment of erectile dysfunction (ED). AIM OF THE STUDY: This study aimed to investigate the active component extract of Chinese yam, determine its effectiveness in hydrocortisone-induced "kidney-yang deficiency syndrome" (KDS-Yang) rats and in oxidatively damaged TM3 cells and explore the underlying mechanism on restoring erectile function. MATERIALS AND METHODS: We clarified the Chinese yam cold-soaking extract (CYCSE) as the main active extract of Chinese yam by a CCK8 assay and further identified its composition. The KDS-Yang rats were induced by intragastric administration of hydrocortisone. After 10 d of CYCSE intervention, cavernous and testis morphology were stained with hematoxylin and eosin. Inducible nitric oxide synthase (iNOS), cyclic guanosine monophosphate (cGMP), testosterone, 8-hydroxy-2-deoxyguanosine (8-OHdG) and superoxide dismutase (SOD) levels were detected by enzyme-linked immunosorbent assay kits. Leydig cells were performed using immunohistochemistry. Reactive oxygen species were measured using a DCFH-DA fluorescent probe, and testicular collagenous fibers were stained with a Masson kit. Detection of testicular apoptosis was performed by a TUNEL assay. Nrf2 and NQO1 mRNA expression levels were measured by qRT-PCR. The protein expression levels of Nrf2, HO-1, TGF-ß1 and SMAD2/3 were analyzed by Western blot. RESULTS: We demonstrated in KDS-Yang rats and oxidatively damaged TM3 cells that CYCSE successfully restored erectile function through ameliorating testicular function. Our data suggested that CYCSE can stimulate the NO/cGMP pathway and restore the cavernous morphology to protect against KDS-Yang-induced ED. It also protected testis morphology, increased Leydig cell proliferation and stimulated testosterone secretion. In the damaged testes, excessive increases in 8-OHdG and inhibition of SOD activity were ameliorated, and the Nrf2/HO-1 signaling pathway was enhanced after treatment with CYCSE, indicating that the antioxidant defense system was activated. These findings were also validated in vitro. Additionally, fibrosis of the testes and TM3 cells was reversed by CYCSE through the TGF-ß1/SMAD2/3 pathway. CONCLUSION: CYCSE has a therapeutic effect on KDS-Yang-induced ED, and the mechanism includes stimulation of testosterone secretion, resistance to oxidative stress and prevention of fibrosis. These findings provide a new scientific verification for the application of Chinese yam in the treatment of KDS-Yang-induced ED.

Integrated mRNA and miRNA transcriptome analysis reveals a regulatory network for tuber expansion in Chinese yam (Dioscorea opposita).

BACKGROUND: Yam tuber is a storage organ, derived from the modified stem. Tuber expansion is a complex process, and depends on the expressions of genes that can be influenced by environmental and endogenous factors. However, little is known about the regulatory mechanism of tuber expansion. In order to identify the genes and miRNAs involved in tuber expansion, we examined the mRNAs and small RNAs in Dioscorea opposita (Chinese yam) cv. Guihuai 16 tuber during its initiation and expansion stages. RESULTS: A total of 14,238 differentially expressed genes in yam tuber at its expansion stage were identified by using RNA sequencing technology. Among them, 5723 genes were up-regulated, and 8515 genes were down-regulated. Functional analysis revealed the coordination of tuber plant involved in processes of cell events, metabolism, biosynthesis, and signal transduction pathways at transcriptional level, suggesting that these differentially expressed genes are somehow involved in response to tuber expansion, including CDPK, CaM, CDL, SAUR, DELLA, SuSy, and expansin. In addition, 541 transcription factor genes showed differential expression during the expansion stage at transcriptional level. MADS, bHLH, and GRAS were involved in cell differentiation, division, and expansion, which may relate to tuber expansion. Noteworthy, data analysis revealed that 22 known tuber miRNAs belong to 10 miRNA families, and 50 novel miRNAs were identified. The integrated analysis of miRNA-mRNA showed that 4 known miRNAs and 11 genes formed 14 miRNA-target mRNA pairs were co-expressed in expansion stage. miRNA160, miRNA396, miRNA535 and miRNA5021 may be involved in complex network to regulate cell division and differentiation in yam during its expansion stage. CONCLUSION: The mRNA and miRNA datasets presented here identified a subset of candidate genes and miRNAs that are putatively associated with tuber expansion in yam, a hypothetical model of genetic regulatory network associated with tuber expansion in yam was put forward, which may provide a foundation for molecular regulatory mechanism researching on tuber expansion in Dioscorea species.

Analysis of the N-Glycoforms and Immunoactivity of Chinese Yam (Dioscorea opposita Thunb.) Glycoprotein 30CYGP.

The major protein in Chinese yam (Dioscorea opposita Thunb.) glycoprotein, 30CYGP, exhibits strong immunomodulatory activities. Research has identified the sequence and structure of 30CYGP; however, 30CYGP N-glycoform composition and immunoactivity remain unknown. We isolated and purified 30CYGP from Chinese yam and used that material to release the N-glycans contained within. The N-glycans were labeled with 1-phenyl-3-methyl-5-pyrazolone and analyzed via ESI-MS and online LC-MS. Additionally, the immunoactivities of 30CYGP and de-glycosylated 30CYGP in the RAW264.7 cell line were investigated. Six 30CYGP N-glycans were observed in total, in which three were modified with xylose (XM: 40%) and three with xylose and fucose (XFM: 60%). Furthermore, de-glycosylated 30CYGP had significantly weaker immunoactivity than 30CYGP. This study demonstrated that novel N-glycoforms may enhance 30CYGP immunoactivity. Further research on the role of varied glycosylation patterns in immunoactivity is needed.

Chemical constituents and antitumor activity from stems and leaves of Dioscorea opposita / 中草药

Objective: To investigate the chemical constituents from the stems and leaves of Dioscorea opposita. Methods: The compounds were isolated and purified by various column chromatographies, and their structures were identified by physiochemical properties and spectroscopic data. The effects of the compounds on the proliferation of human breast cancer MCF-7 cells and human liver cancer HepG2 cells were investigated. Results: Twenty compounds were isolated from the 50% acetone extract of the stems and leaves of D. opposita, which were identified as 1H-indazole (1), 1H-indole-3-carboxaldehyde (2), 1H-indole-3- carboxylic acid (3), 3-(2-oxopropyl)-3-hydroxy-indolin-2-one (4), thymidine (5), uridine (6), 3-hydroxy-3-(2-oxopropyl)-2,4-(1H,3H)- quinolinedione (7), hematinic acid (8), allantoin (9), 2-ethyl-3-methyl-maleimide-N-β-D-glucopyranoside (10), paulownin (11), (+)-8-hydroxypinoresinol (12), (+)-syringaresinol (13), (-)-dihydrodehydrodiconiferyl alcohol (14), (7R,8S)-dihydrodehydro- diconiferyl alcohol-4-O-β-D-glucopyranoside (15), (2E,6S)-6,7-dihydroxy-3,7-dimethyl-2-octenoic acid (16), (2E,4S)-4-hydroxy-2- nonenoic acid (17), (2E,6S)-6-hydroxy-2,6-dimethyl-2,7-dienoic acid (18), amarantholidoside IV (19), (9Z,11E)-13-methoxy- 9,11-octadecadienoic acid methyl ester (20), and their effects on proliferation of MCF-7 cells and HepG2 cells were investigated. compounds 1, 4, 8, 11-15, 18, 20 at a dose of 25μmol/L inhibited the proliferation of MCF-7 cells, and compounds 1, 4, 8, 12-14, 18, 20 at a dose of 25 μmol/L inhibited the proliferation of HepG2 cells. Conclusion: Compounds 1, 3-5, 10-12 and 15-20 are isolated from this plant for the first time, compounds 1, 4,8, 11-15, 18, 20 inhibited the the proliferation of MCF-7 and HepG2 cellssignificantly at certain concentration, showing protent antitumor activity.

Composition and Physicochemical Properties of Three Chinese Yam (Dioscorea opposita Thunb.) Starches: A Comparison Study.

The aim of this work was to compare the composition and physicochemical properties (SEM, XRD, solubility, swelling power, paste clarity, retrogradation, freeze-thaw stability, thermal property, and pasting property) of three Chinese yam (Dioscorea opposita Thunb.) starches (CYYS-1, CYYS-2, and CYYS-3) in Yunlong town, Haikou, Hainan Province, China. Our results show that all the CYYS gave a typical C-type X-ray diffraction pattern. The swelling power of CYYS varied from 10.79% to 30.34%, whereas solubility index was in the range of 7.84-4.55%. The freeze-thaw stability of each CYYS showed a contrary tendency with its amylose content. In addition, CYYS-3 showed the highest To (81.1 °C), Tp (84.8 °C), Tc (91.2 °C), and ΔH (14.1 J/g). The pasting temperature of CYYS-1 increased significantly with sucrose addition. NaCl could inhibit the swelling power of CYYS. There were significant decreases in pasting temperature and pasting time of CYYS when pH decreased.

NMR-based metabolomics approach to investigate the distribution characteristics of metabolites in Dioscorea opposita Thunb. cv. Tiegun.

Dioscorea opposita Thunb. cv. Tiegun (DTT), a type of homologous medicinal plant, is commonly used as food in daily life. However, there has always been confusion regarding removal of the peel, as the nutrient metabolite composition of the peel is unclear. Here, a nuclear magnetic resonance (NMR)-based metabolomics approach was used to determine the metabolite distribution in DTT exclude-peel and peel. Thirteen characteristic metabolites with statistical significance were identified and compared using multivariate, univariate and cluster analyses. The results demonstrated that the peel contained the higher levels of α-glucose, batatasin IV, batatasin I, asparagine, ß-glucose, protodioscin, threonine, protogracillin, dioscin, and ß-sitosteryl acetate, and the samples without the peel had the higher levels of leucine, glutamine and alanine. This study provided scientific data for understanding the distribution characteristics of metabolites in DTT samples, promoting reasonable consumption of DTT.