山药与穿龙薯蓣中尿囊素成分研究

… Significant differences in allantoin contents were observed between interspecific and intraspecific yam varieties, and allantoin contents in the four varieties of D. polystachya were …

Dioscorea polystachya, named Chinese yam, is widely cultivated as a functional food and natural medicine in China. There is currently little information about the chemical characteristics of Dioscorea polystachya in different organs (tuber cortex and tuber flesh) and at various ages. In this study, an ultra‐high‐performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry (UPLC‐QTOF/MS) was used to profile chemical compounds in Dioscorea polystachya. As a result, thirty‐eight compounds were detected in yam tuber cortex and tuber flesh. More compounds were detected in yam tuber cortex than in tuber flesh. Compounds such as dehydroepiandrosterone, allantoin and flavonoids were selected as biomarker candidates. Dehydroepiandrosterone was found more abundant in tuber flesh, while allantoin and flavonoids showed higher levels in tuber cortex. Furthermore, the levels of dioscin, malvalic acid and sucrose differed significantly among age groups and were highest in the tubers at 2 years. While the levels of allantoin, adenosine and glutamine increased with the growing years and were highest at 4 years. Thus, 2‐year old Dioscorea polystachya tubers could be harvested to prepare dioscin, malvalic acid and sucrose supplements. The 4‐year‐old Dioscorea polystachya tubers would be the best choice for obtaining a large amount of allantoin and adenosine in industrial production.

Dioscorea spp. belongs to the Dioscoreaceae family, known as “yams”, and contains approximately 600 species with a wide distribution. It is a major food source for millions of people in tropical and subtropical regions. Dioscorea has great medicinal and therapeutic capabilities and is a potential source of bioactive substances for the prevention and treatment of many diseases. In recent years, increasing attention has been paid to the phytochemicals of Dioscorea, such as steroidal saponins, polyphenols, allantoin, and, in particular, polysaccharides and diosgenin. These bioactive compounds possess anti-inflammatory activity and are protective against a variety of inflammatory diseases, such as enteritis, arthritis, dermatitis, acute pancreatitis, and neuroinflammation. In addition, they play an important role in the prevention and treatment of metabolic diseases, including obesity, dyslipidemia, diabetes, and non-alcoholic fatty liver disease. Their mechanisms of action are related to the modulation of a number of key signaling pathways and molecular targets. This review mainly summarizes recent studies on the bioactive compounds of Dioscorea and its treatment of inflammatory and metabolic diseases, and highlights the underlying molecular mechanisms. In conclusion, Dioscorea is a promising source of bioactive components and has the potential to develop novel natural bioactive compounds for the prevention and treatment of inflammatory and metabolic diseases.

… the highest level of threonine and glutamine,Wenxian sandy soil yam (WS) had the highest level of alanine and malate,and Wuzhi sandy soil yam(ZS) had the highest level of allantoin.…

This study compared the effects of cooking processes (including steaming, boiling, hot-air roasting and microwaving) on the nutrients of Dioscorea opposita planting in sandy soil (SSCY) and loessial soil (LSCY). The contents of crude fiber and reducing sugar increased significantly during cooking for SSCY, whereas those of LSCY remained unchanged. A significant decline in allantoin content was observed in boiled yams (approximately 6.0% for SSCY and 14.1% for LSCY, respectively). Moreover, the differences in chemical compositions between SSCY and LSCY were compared using non-targeted metabolomics. Totally, 656 differential metabolites of LSCY were identified, including lipids, nucleotides, amino acids and derivatives, and organic acids, which might be the key reason why LSCY exhibits higher nutritional values than SSCY. This research contributed to understanding the systematic metabolic changes during planting and the molecular mechanisms influencing the quality formation, providing the theoretical references for the more scientific consumption of Chinese yam.

Abstract Wild yams (Dioscorea spp.) are medicinal plants rich in secondary metabolites of pharmacological interest, mostly allantoin and steroidal saponins. Their natural populations are overexploited and endangered. Cultivated yams could represent an alternative source of metabolites if interesting varieties could be selected. The objectives of the present study were to develop an HPTLC protocol for the simultaneous quantification of allantoin and steroidal saponins in dried yam powders, to compare species and varieties originating from distant geographical origins and to assess their potential as a source of secondary metabolites. Overall, 1151 accessions belonging to six cultivated species were analysed (1000 acc. from Nigeria, and 146 acc. from Vanuatu) and were compared to five commercial powders of wild yam (D. villosa). Allantoin, dioscin, gracillin, protodioscin, protogracillin and five unknown saponins were quantified. Dioscorea villosa powders varied in content and composition, with allantoin ranging from 0.23 to 22.35 mg/g (DW) and total saponins from 37.36 to 129.97 mg/g. Allantoin was present in the six species, with highest values in D. bulbifera bulbils (20.38 mg/g) and D. cayenensis tubers (17.12 mg/g). Steroidal saponins were quantified in three species, D. cayenensis, D. esculenta and D. rotundata, but were absent in D. alata, D. bulbifera and D. dumetorum. Mean total saponins contents were 42.15 mg/g in D. cayenensis, 17.65 mg/g in D. esculenta and 17/44 mg/g in D. rotundata, with accessions presenting very high values in D. cayenensis (78.31 mg/g) and D. rotundata (69.65 mg/g). For both allantoin and saponins, variation was observed within tubers and the tuber peel was richer than the flesh. Cultivated yam species represent a sustainable source of allantoin and steroidal saponins which could be further increased through conventional breeding.

… are to analyze the contents of allantoin and allantoic acid in D. … allantoin and allantoic acid from the mucilage. The total amount of allantoin and allantoic acid of the following Dioscorea (…

… The quantitablity of the NMR method was validated with allantoin, the characteristic metabolite of DA-9801. Similarity analyses of 1 H NMR fingerprints were done based on correlation …

… Dioscorea species contain various saponins, these compounds in D. japonica have been rarely investigated, and allantoin … Quantitative determination of allantoin is difficult due to its …

Abstract China is an important domestication center of yams, and two main yam species of Dioscorea opposita and D. alata are commonly cultivated in China. However, the differences of nutritional and medicinal characteristics between the two species and their subgroups remain unclear, which would greatly affect the resource conservation and commercial utilization of yams. In this study, typical yam resources including the species of D. opposita (wild and cultivated Ruichang yam from southern China, and Tiegun yam from northern China) and two landraces of D. alata (Longyan yam and Anyuan yam from southern China) were selected as materials. Nutritional traits and medicinal characteristics were determined and analyzed respectively. The results showed that there was no significant differences in the content of most nutrients between D. opposita and D. alata, but most cultivated Ruichang yam of D. opposita showed higher levels of starch, soluble sugar, sucrose, and ascorbate in tuber than that in yam from D. alata. Moreover, an UPLC-MS method was developed for identification and determination of medicinal characteristics in the two species. The results showed that allantoin can be detected in all selected samples. Cultivated Ruichang yam of D. opposita possessed the highest allantoin content among the tested materials, and was significantly different with that in Tiegun yam and D. alata. Dioscin was not detected in D. alata. Overall, there was little difference in nutritional composition between D. opposita and D. alata, but the medicinal quality of D. opposita was better than that of D. alata. Due to the outstanding comprehensive quality, the local variety of cultivated Ruichang yam can be further developed and utilized.

… However, studies on the allantoin content of Chinese yams and changes … 1, the allantoin content changed in volatility after 45 day of storage. At the end of the storage period, the content …

Saline-alkali stress (SAS) significantly impairs crop growth, yield and quality, while allantoin plays a crucial role in enhancing plant tolerance to this stress. Yam (Dioscorea opposita Thunb.) has substantial nutritional and medicinal value. However, the regulatory mechanism of allantoin in regulating yam growth and nutritional quality under SAS remains largely unclear. In this study, we found that SAS severely inhibited the growth and root development of yam bulbil seedlings. Specifically, in leaves, the contents of osmotic regulators (e.g., proline, soluble sugar) and malondialdehyde (MDA), along with the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), were significantly increased. Additionally, leaf Na+ content was increased, K+ content was decreased, and the Na+/K+ ratio was significantly elevated. Meanwhile, the contents of allantoin, diosgenin, and polysaccharides in tubers were significantly increased. Overexpression of the allantoin synthase gene DoAS in Arabidopsis thaliana further enhanced its tolerance to SAS. Furthermore, compared with the SAS-only group, allantoin treatment significantly improved yam seedling growth, reduced leaf proline and MDA contents, enhanced SOD and POD activities, decreased the Na+/K+ ratio, increased tuber yield and contents of major active components, and lowered tuber Na+ content. Taken together, allantoin significantly improves ionic balance and antioxidant capacity in yam bulbil seedlings under SAS, thereby promoting seedling growth and nutrient accumulation in tubers. This study thus highlights the critical role of allantoin in regulating the growth and nutrient accumulation in tuber crops under SAS.

With the aging process, a loss of skeletal muscle mass and dysfunction related to metabolic syndrome is observed in older people. Yams are commonly use in functional foods and medications with various effects. The present study was conducted to investigate the effects of rhizome extract of Dioscorea batatas (Dioscoreae Rhizoma, Chinese yam) and its bioactive compound, allantoin, on myoblast differentiation and mitochondrial biogenesis in skeletal muscle cells. Yams were extracted in water and allantoin was analyzed by high performance liquid chromatography (HPLC). The expression of myosin heavy chain (MyHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), sirtuin-1 (Sirt-1), nuclear respiratory factor-1 (NRF-1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) or western blot. The glucose levels and total ATP contents were measured by glucose consumption, glucose uptake and ATP assays, respectively. Treatment with yam extract (1 mg/mL) and allantoin (0.2 and 0.5 mM) significantly increased MyHC expression compared with non-treated myotubes. Yam extract and allantoin significantly increased the expression of PGC-1α, Sirt-1, NRF-1 and TFAM, as well as the phosphorylation of AMPK and ACC in C2C12 myotubes. Furthermore, yam extract and allantoin significantly increased glucose uptake levels and ATP contents. Finally, HPLC analysis revealed that the yam water extract contained 1.53% of allantoin. Yam extract and allantoin stimulated myoblast differentiation into myotubes and increased energy production through the upregulation of mitochondrial biogenesis regulators. These findings indicate that yam extract and allantoin can help to prevent skeletal muscle dysfunction through the stimulation of the energy metabolism.

The objective of this study was to investigate the therapeutic efficacies of crude yam (Dioscorea batatas) powder (PY), water extract of yam (EY), and allantoin (the active constituent of yam) in streptozotocin (STZ)-induced diabetic rats with respect to glucose, insulin, glucagon-like peptide-1 (GLP-1), C-peptide, glycated hemoglobin (HbAlc), lipid metabolism, and oxidative stress. For this purpose, 50 rats were divided into five groups: normal control (NC), diabetic control (STZ), and STZ plus treatment groups (STZ + PY, STZ + EY, and STZ + allantoin). After treatment for one-month, there was a decrease in blood glucose: 385 ± 7 in STZ, 231 ± 3 in STZ + PY, 214 ± 11 in STZ + EY, and 243 ± 6 mg/dL in STZ + allantoin, respectively. There were significant statistical differences (p < 0.001) compared to STZ (100%): 60% in STZ + PY, 55% in STZ + EY, and 63% in STZ + allantoin. With groups in the same order, there were significant decreases (p < 0.001) in HbAlc (100% as 24.4 ± 0.6 ng/mL, 78%, 75%, and 77%), total cholesterol (100% as 122 ± 3 mg/dL, 70%, 67%, and 69%), and low-density lipoprotein (100% as 29 ± 1 mg/dL, 45%, 48%, and 38%). There were also significant increases (p < 0.001) in insulin (100% as 0.22 ± 0.00 ng/mL, 173%, 209%, and 177%), GLP-1 (100% as 18.4 ± 0.7 pmol/mL, 160%, 166%, and 162%), and C-peptide (100% as 2.56 ± 0.10 ng/mL, 129%, 132%, and 130%). The treatment effectively ameliorated antioxidant stress as shown by a significant decrease (p < 0.001) in malondialdehyde (100% as 7.25 ± 0.11 nmol/mL, 87%, 86%, and 85%) together with increases (p < 0.01) in superoxide dismutase (100% as 167 ± 6 IU/mL, 147%, 159%, and 145%) and reduced glutathione (100% as 167 ± 6 nmol/mL, 123%, 141%, and 140%). The results indicate that yam and allantoin have antidiabetic effects by modulating antioxidant activities, lipid profiles and by promoting the release of GLP-1, thereby improving the function of β-cells maintaining normal insulin and glucose levels.

Yams (Dioscorea spp.) are widely cultivated as edible resources and medical materials in China. Characterizing chemical compositions in yam germplasm is crucial to determine their diversity and suitability for food and medicine applications. In this study, a core germplasm containing 25 yam landraces was used to create an effective classification of usage by characterizing their nutritive and medicinal compositions. All studied landraces exhibited high contents of starch from 60.7% to 80.6% dry weight (DW), protein (6.3–12.2% DW), minerals (especially Mg 326.8–544.7 mg/kg DW), and essential amino acids. Allantoin and dioscin varied considerably, with values of 0.62–1.49% DW and 0.032–0.092% DW, respectively. The quality variability of 25 yam landraces was clearly separated in light of UPGMA clustering and principal component analysis (PCA). Using an eigenvalue ≥1 as the cutoff, the first three principal components accounted for most of the total variability (62.33%). Classification was achieved based on the results of the measured parameters and principal component analysis scores. The results are of great help in determining appropriate application strategies for yam germplasm in China.

ETHNOPHARMACOLOGICAL RELEVANCE Dysfunction of glucose metabolism is associated with the occurrence of metabolic syndromes, including type 2 diabetes mellitus (T2DM). In this study, we investigated the anti-diabetic effects of yam extract and allantoin in high-fat-diet (HFD) and streptozotocin (STZ)-induced diabetic mice and the mechanism of action on the dysfunction of the liver, pancreas, and skeletal muscle. MATERIALS AND METHODS Male C57BL/6 mice were induced into a diabetic condition by HFD for 16 weeks and a single injection of STZ (120 mg/kg) and then orally administered yam extract (500 and 1000 mg/kg) or allantoin (20 and 50 mg/kg) once daily for 4 weeks. The changes in physiological parameters, serological parameters, and morphology of tissues were investigated. The expression levels of antioxidant enzymes, biogenetic proteins, and myogenetic proteins were determined in the liver, pancreas and skeletal muscle tissues of mice. RESULTS The administration of yam extract and allantoin at high doses in HFD-/STZ-induced diabetic mice compared with the control group significantly decreased the increase in body weight, caloric intake, and water intake. Yam extract and allantoin significantly decreased high glucose and leptin, total cholesterol, triglyceride, low-density lipoprotein-cholesterol, aspartate transaminase, alanine aminotransferase levels and increased insulin and albumin levels in the plasma of mice. Yam extract and allantoin inhibited the structural damage of the liver with regard to fat accumulation, the pancreas with regard to hyperplasia of Langerhans' islets, and skeletal muscle with regard to atrophy and significantly increased the expression of antioxidant enzymes and mitochondria-mediated biogenetic factors in the liver, pancreas, and muscle tissues. In addition, yam extract and allantoin significantly increased the expression of myogenetic proteins in skeletal muscle tissues. CONCLUSION Our results indicated that yam extract and allantoin improve diabetic symptoms through the regulation of oxidation and glucose imbalance in liver, pancreas, and skeletal muscle tissues in mice. These findings suggest that yam extract and allantoin can be used as antidiabetic factors in supplementary foods and medications for T2DM patients.

… Dioscorea rhizome contains ureides, including allantoin, used for the prevention of inflammation and ulcers (4). Moreover, the Dioscorea species accumulate allantoin … Protein content …

… The only other report of the occurrence of allantoin in Dioscorea species is in a note on its … Following the discovery of allantoin in the acetone extracts and characterization by mass …

… Dioscorea Rhizome is commonly used in traditional herbal … Allantoin, as the principle active compound, is abundant in D. … present study confirmed the presence of allantoin in DRWE. …

… HPLC analysis was performed for the quantitative determination of dioscin and allantoin, the marker components of DJ and DN, in DA-9801. As shown in Fig. 1A and B, DA-9801 …

Objective. Allantoin is the primary active compound in yams (Dioscorea spp.). Recently, allantoin has been demonstrated to activate imidazoline 3 (I3) receptors located in pancreatic tissues. Thus, the present study aimed to investigate the role of allantoin in the effect to improve damage induced in pancreatic β-cells by streptozotocin (STZ) via the I3 receptors. Research Design and Methods. The effect of allantoin on STZ-induced apoptosis in pancreatic β-cells was examined using the ApoTox-Glo triplex assay, live/dead cell double staining assay, flow cytometric analysis, and Western blottings. The potential mechanism was investigated using KU14R: an I3 receptor antagonist, and U73122: a phospholipase C (PLC) inhibitor. The effects of allantoin on serum glucose and insulin secretion were measured in STZ-treated rats. Results. Allantoin attenuated apoptosis and cytotoxicity and increased the viability of STZ-induced β-cells in a dose-dependent manner; this effect was suppressed by KU14R and U73112. Allantoin decreased the level of caspase-3 and increased the level of phosphorylated B-cell lymphoma 2 (Bcl-2) expression detected by Western blotting. The improvement in β-cells viability was confirmed using flow cytometry analysis. Daily injection of allantoin for 8 days in STZ-treated rats significantly lowered plasma glucose and increased plasma insulin levels. This action was inhibited by treatment with KU14R. Conclusion. Allantoin ameliorates the damage of β-cells induced by STZ. The blockade by pharmacological inhibitors indicated that allantoin can activate the I3 receptors through a PLC-related pathway to decrease this damage. Therefore, allantoin and related analogs may be effective in the therapy for β-cell damage.

… is the final product of purine catabolism, and is a common constituent of Dioscorea species … The optimized solidphase extraction procedure was applied to separate allantoin from …

… A new CE method has been developed for the separation and determination of allantoin, … , which has been successfully used for determination of allantoin, choline and arginine in some …