• Journal of Nutrition and Health
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• v.33 no.2
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• pp.115-123
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• 2000

This study evaluates the effect of Dioscorea japonica Thunb subfractions on hyperglycemia and the composition of energy metabolites in diabetic rats. Diabetes emllitus was induced in male Sprague-Dawley rats by an injection of streptozotocin(STZ) dissolved in a citrate buffer into the tail vein at a dose of 45㎎/㎏ of body weight. Diabetic rats were assigned to 6 groups; STZ-control, subfraction A, B , C, D and E groups. All groups were fed an AIN-76 diet. The second butanol fraction of Dioscorea administered orally with carboxymethyl cellucose for 10 days after the STZ injection Body weight gain, diet intake and organ weights were monitored Levels of hematocrit, blood glucose, liver and muscle glycogen were measured. Levels of cholesterol, triglycerides and free fatty acids were also assayed. Body weight losses were observed by subfraction A group. Liver and kidney weights were not affected in any of the subgractioned groups. The decrease of blood glucose in daibetic rats which were fed Dioscorea japonica Thunb was significantly greater than the dicrease of blood glucose in the STZ-control group. cholesterol plasma level was not influenced in any subfraction of Dioscorea japonica Thunb. Liver triglyceride levels were significantly lowered in subfraction A compared with the STZ-control group. This study's results suggest that oral administration of subfraction C of Dioscorea japonica Thunb frction is capabl of reducing blood glucose, plasma triglyceride and free fatty acid levels, and therefore Dioscorea japonica Thunb may contain antihyperglycemic compounds.

• Journal of Nutrition and Health
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• v.31 no.7
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• pp.1093-1099
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• 1998

Dioscorea japonica Thunb its effects has been used in f31k remedies f9r various purposes including treatment of diabetes, on hypoglycemic actiity and energy metabolism were investigated. The plant was extracted with methanol(MeOH) and fractionated into four layers hexane, chloroform(CHCI$_3$), butanol(BuOH), and $H_2O$. Diabetes mellitus was induced in male Sprague-Dawley rats by the injection of streptozotocin(STZ) into tail vein at a dose of 45mg/kg body weight(BW). Sprague-Dawley male rats weighing 160-200g were divided into five groups a diabetic control and four experimental groups such as hexane group, CHCl$_3$ group, BuOH group, and $H_2O$ group. The rats of all groups were fed on a AIN-76 diet and the four experimental groups were orally administered each fraction(500mg/kg BW) for 12 days. The diabetic control group was orally administered 5% carboxymethyl cellulose. The body weights were monitored and the concentrations of blood glucose were determined. The levels of glycogen and protein in liver were also measured. The plasma levels of cholesterol, triglyceride (TG), and fee fatty acid(FFA) were also analysed. The body weight gain was higher in the $H_2O$ group than in the control group. Heart weight was significantly reduced by administrations of Dioscorea japonica Thunb. The extents of blood glucose decrement in BuOH and $H_2O$ group were greater than that found in the control group. The muscle protein levels showed significantly higher amounts in all experimental groups. Glycogen levels were higher in the BuOH group than in the control group. The levels of TG were decreased in all experimental groups and the levels of plasma FFA were lower in the BuOH group. The plasma cholesterol levels were not influenced by these four fractions in diabetic rats. These results suggest that the orally administered H2O fraction of Dioscorea japonica Thunb exhibited hypoglycemic effects in STZ induced diabetic rats. (Korean J Nutrition 31(7) : 1093-1099, 1998)

• Natural Product Sciences
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• v.25 no.3
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• pp.261-267
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• 2019

The rhizomes of Dioscorea japonica Thunb. are widely consumed as food and also used to treat diabetes and polyuria in Korea. This study was undertaken to study the anti-atopic dermatitis effects of a 95% ethanolic extract (DJE) of D. japonica in an oxazolone-stimulated murine model of atopic dermatitis (AD). The therapeutic effects of DJE on AD-like skin lesions were assessed on both ears. DJE (1%) or dexamethasone (0.5%; the positive control) were applied to skin lesions for three weeks. Serum levels of IgE and IL-4 were assessed by ELISA (enzyme-linked immunosorbent assay). Histopathological examinations were performed by hematoxylin and eosin (H&E) and toluidine blue staining and revealed DJE significantly reduced dermal thickness and inflammatory cell infiltration when applied to oxazolone-treated ear skin. DJE-treated AD mice also showed lower serum levels of IgE and IL-4 than oxazolone-stimulated controls. Our findings demonstrate DJE might be a useful safe, topical agent for the treatment of atopic diseases.

• Korean journal of food and cookery science
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• v.11 no.3
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• pp.267-273
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• 1995

Twenty five cooking recipe with yam (Dioscorea japonica Thunb) have been developed and their hypoglycemic effects on diabetic patients were investigated. The results of the sensory evaluations revealed that the tested recipe were in good scores (overall acceptability scores 3.30-4.33) except Chojuli. The 10-panel members indicated that the yam cookings were more acceptable when they were cooked with other vegetables. Twenty seven diabetic patients were entered in a general hospital during the 2-month experimental period and they were allowed to consume the diet with yam cooking dish, 75 g of yam a day. The fasting blood glucose and 2-hour postprandial blood glucose levels were determined. The diabetic patients who consumed yam showed the lower blood glucose levels than those patients who were controlled with the hospital diet only. The hypoglycemic effects of the yam were more evident in the patients who were injected with insulin. The constant lowering effects of blood glucose levels were observed in the normal subjects who had taken the yam cookery, leading to that one subject who started with a low blood glucose level must stop the yam consumption after 10 days.

• Korean Journal of Pharmacognosy
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• v.21 no.4
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• pp.274-283
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• 1990

This study was conducted to further characterize mucilages from Dioscoreae Rhizoma, which have been known to be proteoglycans. We chose the two types of yams, Dioscorea batatas Dec. (club-like) and D. japonica Thunb. (cane-like). Repeated gel filtration of a dialyzed water extract of each fresh yam on Bio-gel P-100 and then Sephadex G-150 columns completely separated the mucilage from protein. Furthermore, gel filtration of a water extract from each yam processed by steaming and drying on the Bio-gel P-100 column gave only one polysaccharide peak without protein. These results revealed that the mucilages of yams were only composed of polysaccharide. Then we assessed some properties of the mucilages under three kinds of criteria: a complex-forming capacity between mucilage and alcian blue, mannose content in the mucilage, and viscosity. The complex-forming capacities of two types of fresh yams were closely similar with each other, but the processing of two types of the fresh yams greatly lowered the complex-forming capacity and viscosity.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 1995.05a
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• pp.212-212
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• 1995

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.297-300
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• 2002

Endogenous ABA and batatasins were first quantified in the stored tubers and bulbils of the Chinese yam, Dioscorea opposita Thunb. cv. 'Tsukune' by GC-MS with comparison of internal standard, and sugar content was also analyzed by HPLC with comparison of external standard. Endogenous ABA content in stored tubers and bulbils was rapidly decreased as storage period prolonged. ABA content of the bulbils was always higher than that of tuber during storage periods. All batatasins of stored tubers and bulbils at 30 days after storage decreased steadily compared to 120 days after storage. On the contrary, batatasin-Ⅲ of the stored tuber and bulbils was only decreased at 60 days after storage. In Dioscorea opposita Thunb. cv. 'Tsukune' like D. japonica, D. alata, and D. bulbifera, may be controlled by endogenous batatasins and ABA, In these compounds, batatasins rather than ABA might be closely related to dormancy-inducing compound during dormancy of the Chinese yam, Dioscorea opposita Thunb. cv. Tsukune.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.540-543
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• 2007

We have investigated the vegetation in the peninsula located in Ongjeong-Li Seomyeon in Youngweol-gun. Since this is a limestone area, boxtrees, Abelia mosanensis T. H. Chung ex Nakai, and Selaginella stauntoniana Spring were abundant, as these are types of vegetation characteristic of limestone areas. Pinus densiflora S. et Z. was the most dominant woody plant, but vegetational changes, such as the dominance of Quercus variabilis Blume, Quercus dentata Thunb, and Quercus mongolica Fischer, were observed in spots. In particular, the growth of nursery plants of pinus densiflora S. et Z. was not observed, and young trees like Quercus mongolica Fischer grow as low vegetation of Pinus densiflora S. et Z.. Thus, the ecological succession of Quercus mongolica Fischer is predicted. Outside the investigation area, as herbaceous plants, various vegetations were observed, including Selaginella stauntoniana Spring, Thalictrum coreanum H. Lev., Mukdenia rossii(Oliv.) Koidz., Platanthera freynii Kraenzl., Cephalanthera longibracteata Blume, Potentilla dickinsii Franch., Patrinia rupestris(Pall.) Juss., Swertia pseudochinensis H. Hara, Vicia venosa(Willd.) Maxim., Pyrola japonica Klenze ex Alef., Disporum smilacinum A. Gray, Artemisia stolonifera(Maxim.) Kom. for. Stolonifera, Smilax nipponica Miq., Adenophora triphylla var. japonica(Regel) H. Hara, Isodon inflexus(Thunb.) Kudo, Gentiana scabra Bunge for. Scabra, Polygonatum odoratum var. pluriflorum(Miq.) Ohwi, Dioscorea quinqueloba Thunb., Syneilesis palmata(Thunb.) Maxim., Asparagus schoberioides Kunth, Eupatorium japonicum Thunb. ex Murray, Galium kinuta Nakai & Hara, Saxifraga fortunei var. incisolobata, Lilium amabile Palib., Siberian iris, Dictamnus dasycarpus Turcz., Atractylodes ovata(Thunb.) DC., and Lysimachia clethroides Duby.

• KSBB Journal
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• v.31 no.1
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• pp.58-65
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• 2016

In this study, Arthrobacter scleromae SYE-3, which was isolated from indigenous plant in a subtropical region, Neigeria, with plant growth promoting activity was evaluated to determine the optimal culture condition. A bacterial strain SYE-3 had the IAA productivity ($89.15{\pm}0.36mg/L$) and ACC deaminase activity ($0.20{\pm}0.06$ at 72 hours). Also, optimal culture conditions such as temperature and pH of strain SYE-3 were $20^{\circ}C$ and 10 in LB medium, respectively. Strain SYE-3 had up to 3% salt tolerance in the LB medium. Plant growth promoting ability of strain SYE-3 using yam (Dioscorea japonica Thunb.) was evaluated. As a result, strain SYE-3 had showed very powerful effect on the increase of the shoot length and root biomass of yam (190.0% and 282.41% increase for 112 days, respectively). These results indicated that Arthrobacter scleromae SYE-3 can serve as a promising microbial resource for the biofertilizers of subtropical crops.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.108-113
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• 1999

Natural products derived from not only medicinal but edible plants have been used as sources of folk remedies and other useful materials, like as appetizers, health supplements and food additives. A short-term in vitro biomarker assay was accompilshed to assess cytotoxic activity on the human lung and ovary adeno cancer cell lines based on sulforhodamine B (SRB) method. As a result, the EtOAc soluble fractions from Trichosanthes kirilowii Max. and Dioscorea japonica Thunb. showed potent cytotoxicity as a below 30% of growth ratio of cancer cell at a concentration of 40 $\mu\textrm{g}$/ml on lung and ovary adeno cancer cell lines, and lung cancer cell line, respectively. Cytotoxic activity present in plant extracts appear to be promising candidates as functional foods among Korean wild edible plants, and further studies are warranted.