Dissertations / Theses on the topic 'Dioscorea alata L'
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Némorin, Alice. "Acquisition de connaissances sur la génétique de l'espèce Dioscorea alata L. pour la production de variétés polyploïdes." Thesis, Antilles-Guyane, 2012. http://www.theses.fr/2012AGUY0519/document.
Full textWe studied polyploidisation phenomena in the yam Dioscorea alata that includes three cytotypes -diploid (2n=40), triploid (2n=60) and tetraploid (2n=80) -in order to optimise polyploid hybrid production strategies. In this complex polyploid, the increase in ploidy is correlated with an increase in vigour and higher and more stable yields. We first showed the autotetraploidy of tetraploid varieties using three different approaches: heredity analyses of microsatellite markers, the observation of double reduction phenomena, and the study of meiosis of pollen mother cells. We then determined the mechanisms most likely to be at the origin of natural polyploids through the study of the transmission of parental heterozygoty using microsatellites and the study of incompatibilities at the endosperm level at the time of different intracytotypic and intercytotypic crosses using flow cytometry. The results obtained reveal that the polyploids of D. alata probably appeared through the formation of non-reduced gametes of diploid clones. The triploid pool would then have been constituted and diversified through the female pathway as a result of the non-viability of intercytotypic crosses and the sterility of female and male triploids. The tetraploid pool would have appeared as a result of the union of two non-reduced gametes of diploid clones (bilateral sexual polyploidisation). This pool would then have diversified through intercytotypic crosses with the formation of 2n gamètes through both the female and the male pathway, as well as by intracytotypic crosses within the 4X pool
Twyford, Cedric T. "Somatic embryogenesis in the food yam Dioscorea alata L., cultivar Oriental Lisbon." Thesis, University of London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324906.
Full textKandasamy, Kodi Isparan. "Tissue culture studies on the interactions between the yam anthracnose pathogen and Dioscorea alata L." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321759.
Full textBorgès, Garcìa Misterbino. "Caractérisation de la diversité génétique et diagnostic viral de Dioscorea alata L. En vue de sa micropropagation et conservation à Cuba." Antilles-Guyane, 2011. http://www.theses.fr/2011AGUY0446.
Full textThe yam is an important culture in the mountainous zones of the oriental region of Cuba, where exist the biggest diversity ofDioscorea spp. The factor limiting major of the local production is the lack of quality seeds. The production development required a better knowledge of the biodiversity ofthe cultivated clones and viruses associated, and by the development of a methodology of micropropagation permitting to provide the healthy material to the agricultural production. In this study, the characterizing of the D. Alata germoplasm in the Eastern region of Cuba, the realisation a virus diagnosis through the most recent molecular techniques, and production the material healthy of the Caraquefio clone by methods of micropropagation and conservation were carried out. Ten representative accessions were characterized using morphological and agronomical indicators and five molecular markers corresponding to Dioscorea genera-derived micro satellites. The Coating - PCR method to detect badnavirus and the method Coating RT-PCR to detect the potexvirus, potyvirus (YMV and YMMV) and universal potyvirus were used. For the first time to Cuba, the existence of badnavirus has been detected. The mopho-agronomic analyses put in evidence the existence of six different phenotypes while the molecular analysis revealed the existence of four different genotypes. A complete methodology for the propagation and conservation the material healthy of the Caraquefio clone, in in vitro culture and to the field was finalized. This methodology is successfully validated in relation to the morpho-agronomical, histological and molecular studies for its application at a commercial scale. This methodology also assured the good state phytosanitaire of the plant material, so that this methodology can be applied in conditions similar to another clones
Bazabakana, Romain. "Contribution à l'effet de l'acide jasmonique exogène sur la tubérisation, la dormance et la germination dezs microtubercules chez Dioscorea alata L. (Dioscoreaceae)." Doctoral thesis, Universite Libre de Bruxelles, 2001. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211655.
Full textMuñoz, Cuervo Ismael. "Évaluation de la diversité du contenu phytochimique de trois espèces à racines et tubercules amylacées tropicales, le taro, la grande igname et le manioc." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10099.
Full textTaro (Colocasia esculenta L.), the greater yam (Dioscorea alata L.) and cassava (Manihot esculenta Crantz) are three important staple crop species from tropical and subtropical regions. In order to evaluate the diversity in bioactive molecules of these three species, we have developed medium throughput HPLC/DAD and GC/MSbased analytical methodologies to estimate the contents of 129 carotenoids and phenolic/indolic compounds and 16 organic/fatty acids in the consumed underground tissues. The contents of these substances have then been quantified for the first time in a large sampling representative of the agro-morphological biodiversity of these three species (respectively 173, 113 and 79 landraces of taro, greater yam and cassava that were cultivated on a common site). Results demonstrate the existence of a large qualitative and quantitative diversity of chemical traits and the absence of clear-cut chemotype. Most secondary metabolites have only been detected in few landraces in agreement with results from previous studies on the diversity, and distribution, of neutral genetic alleles in these plants. Though well appreciated by consumers, colored and mouth-perceivable substances have not been subjected to major content improvement through targeted selection and are in fact only detectable in a limited number of landraces. As a whole, these results support the importance of participatory selection by small farmers in the creation, and maintaining, of a large chemical diversity in these species. They also offer novel tools and perspectives for the improvement of the nutritional value of these species by plant breeders
Malapa, Roger. "Description de la diversité de Dioscorea alata L. Du Vanouatou à l’aide de marqueurs agro-morphologiques et moléculaires (AFLP) : Relations avec les autres espèces de la section Enanthiophyllum." Rennes, Agrocampus Ouest, 2005. http://www.theses.fr/2005NSARC078.
Full textThis thesis, which’s goal is to describe the diversity of cultivated yam (Dioscorea alata L. ) cultivars and their relation with D. Nummularia Lam. , was conducted between Montpellier (France) and Vanuatu. The plant material that was studied came from the Vanuatu National Collection, and, in the case of D. Nummularia, was completed by material stemming from prospections. Elite accessions of D. Alata originating from Melanesia and Asia were also used in this comparative study. Traditional knowledge shows that D. Alata and D. Nummularia comprise a number of cultivars. These are used for consumption, as well as to acquire prestige. The evaluation of the diversity of 331 accessions of D. Alata using 26 agromorphological descriptors confirms the great phenotypical diversity of this species. The study of ploidy level reveals that this diversity also posses a cytological basis, with ploidy levels ranging from 2n = 4x, 6x and 8x for D. Alata, and 2n = 6x, 8x, 10 to 12x for D. Nummularia. Ceremonial cultivars are essentially hexa- and octaploids. The diversity was also studied at the molecular level using AFLPs. D. Nummularia appears to be heterogeneous taxon, which could include four distinct species, although sharing a common genetic background. The results of this study are discussed within the perspective of the genetic improvement of cultivated yam, D. Alata
Pan, Chia-rue, and 潘嘉如. "Preparation of Hydrolysates from Tuber of Yam (Dioscorea alata L.)." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/46265956979187683708.
Full text國立中興大學
食品科學系
88
The tuber of yam contains sufficient of amino acid, proteins, mucin, allantoin, choline, fiber, vitamin A, B1, B2, C, and Ca, P, Fe, I, and etc. It is a good nutrient source for human being. Protein hydrolysates is a product from chemical or enzymatic hydrolytic reaction as macro protein molecular are hydrolyzed to an increasing degree, they form aggregates with lower average molecular weights, including proteoses, peptones, peptide, amino acid mixtures, and free amino acid mixture. From a nutritional point of view, the demand for protein or more amino acid can be fulfilled equally well either by intake of free amino acid, protein hydrolysates, or by intact protein assuming the bioavailability is the same. The objective of this investigation was to study the production and composition of hydrolysates from tuber of yam (Dioscorea alata L.) using hydrochloric acid. The characteristics of the yam hydrolysates were examined including, total nitrogen (TN%), formol nitrogen (FN%), degree of hydrolysis (DH%), dextrose equivalent (DE%), analysis of amino acid compositions, the amount of soluble solid, reducing sugar, total sugar, and salt content. Besides, the color and sensory evaluation analysis were investigated. Results showed that as the acid concentration and hydrolysis time were increased, FN% and DH% of the hydrolysates were increased, and color became darker. Amino acid compositions of the yam hydrolysates were mainly glutamic acid (Glu) and aspartic acid (Asp) which contribute to its flavor attribute. When acid concentration was increased, the soluble solid and salt content were also increased, but the hydrolysis time and acid concentration were not significantly affected by TN%. When acid concentration and hydrolysis time increased, reducing sugar, total sugar, and DE% of the hydrolysates were decreased, which explain that in the presence of sugar and protein in yam tuber, Maillard reaction and caramelization reaction did occur. Sugar in the hydrolysate was also affected by acid and heat. Because the sugar was used for Maillard reaction, the DE% value cannot mean the true status. When acid concentration, hydrolysis time, and pH of the hydralysate were increased, the hydrolysates color was even darker. Results of the sensory experiment showed that the hydrolysates of the yam tuber is a promising ingredient for addition in sport drinks. In conclusion, the higher acid concentration and longer hydrolysis time demonstrated efficient hydrolysis to obtain small molecular yam tuber hydrolysates. In the future, the yam hydrolysates will be used as a functional food, additive for designing new formulation in soft drink products. In the mean that, sure this product can be commercialized and its overall acceptability could be even higher.
Chien, Hsu-Chi, and 簡旭祺. "Study of color and texture changes of yam(Dioscorea alata L.)." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/78404872237071962110.
Full text國立臺灣大學
園藝學系研究所
86
Color and texture changes of minimally processed yam (Dioscorea alata L.) slices during storage were studied. When unpackaged yam slicesstored at room temperature (25*2oC) for 48hrs., the Hunter''s L value of all three yam cultivars, Tsun, Chang, and Huang, were decreased as the storage time increase d. The increases of Hunter''s +a value with time in Tsun and Huang yam slices are correlated with the degree of browning. The polyphenol oxidase (PPO) activ ities of three cultivar yam slices are increased with storage time within 24hr s. The highest PPO activity of Tsun yam slices demonstrate the most severe br owning of the samples. The peroxidase (PO) activities of three cultivar yam slices also increase within 12hrs at room temperature storage. Although the PO activities of Chang yam slices are the highest among cultivars, less sever ebrowning than Tsun yam slices demonstrates that PO play little role on thebro wning of yam slices.All three cultivars of yam slices, vacuum packaged in polypropylene (PP) bags and stored at 3oC for 14days, show little browning occurred. The results of Texture Profile Analysis (TPA) indicate that,amongthree yam cultivars, the hardness and adhesiveness of fresh yam slices aresiming yam . However, Tsun and Chang yam slices present better fracturability than Hua ng yam slices; and Huang yam slices present better springness,cohesiveness, gu mminess, and chewiness than Tsun and Chang yam slices. When stored yam slices at room temperature without packaging, loss of moi- sture and decrease of starch content resulted in the increase of yam slice hardnesses. This is especially true in the Tsun and Chang yams. The increase in reducing sugar content , which probably due to the concentration effect of moisture loss and the starch hydrolysis, have correla tion coefficient of0.66- 0.70 with the increase of yam hardnesses.
Hsin-Yu, Chen, and 陳信宇. "Studies on the genomic and the regulatory sequence of the storage protein dioscorin genes of yam(Dioscorea alata L.)." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/79971342597236672358.
Full text國立嘉義大學
生物科技研究所
94
Dioscorin is the major storage protein in yam (Dioscorea alata L.)。In this study, four fragments of the genomic sequences of the storage protein dioscorin genes were cloned by nested PCR and TAIL-PCR(Thermal asymmetric interlaced PCR)with several primer pairs designed according to the dioscorin A mRNA sequences published in NCBI Genbank. The dioscorin gene should be comprised of 7 exons and 6 introns. In the intron assay, we cloned 17 different introns totally. The 1st intron has 2 different kinds, the 2nd has 2, the 3rd has 3, the 4th has 3, the 5th has 3, and the 6th has 3. We concluded that there are at least 6 members of dioscorin A in the dioscorin gene family according the 6 cloned fragments combined with the 3rd and the 4th different introns. Furthermore, the 5’-upstream sequence of the yam storage protein dioscorin gene was isolated by TAIL-PCR from the genomic DNA. The product was 491 bp with the 466 bp upstream to the translation start site of the dioscorin gene and 74 bp 5’-UTR. After the sequence alignment and identification analysis in the database, the putative promoter and several putative cis-acting elements were predicted. The sequence was used to generate 7 fragments of 5’ serial deleted sequence and fused with GUS gene of Ti-plasmid. The agroinfiltration method was applied for transient expression in the leaves of tobacco seedlings to rapidly examine its transcriptional activity and confirm the cis-acting elements .
Yu, Chi-Chun, and 游惠君. "Studies on regulatory region of a storge protein gene in Dioscorea alata L. bulbil." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/60738893036642325585.
Full text國立嘉義大學
生物科技研究所
92
Yam is one of five types tuber crops in the world. Its tuber contains about 6-8﹪crude protein. According to previous studies, the predominant protein is a storage protein, namely dioscorin. Which represents more than 85﹪of total protein. As compared with other storage proteins from various tuber crops, such as potato storage protein (i.e. patatin, about 40~45﹪of the total protein), the considerably higher yield has made the studies of the regulation of dioscorin gene greatly interested. cDNA sequence encoding dioscorin has been reported previously. In our study, we have shot for two objectives. One is to establish yam tissue culture system. And, the other one is to investigate the dioscorin regulator region. In tissue culture study, we have been able to induce bulbil growth from stem nodal, and grow the suspension culture by using the bulbil cell. We expect this bulbil cell would be a suitable material used later in the genetic transformation studies. In the dioscorin regulator region study, we have isolated the bulbil’s total protein from D. alata, analyzed the proteins by SDS-PAGE, and isolated the most abundant protein from the gel for sequencing. Based on the results from LC-MASS sequencing, the primary sequence of the isolated protein is highly homologous to the dioscorin A from D.alata (tainong 1) and D.cayenensis. In addition, the isolated bulbil’s protein (~95% total protein) was further confirmed by histochemistry to be dioscorin. Another attempt has been taken to isolate the regulatory sequence of dioscorin gene according to the published cDNA sequence. By using intron assay method, we have obtained a short intron, 168 bp, located near the 5’ end of cDNA. Furthermore, by using inverse PCR method, we have obtained a 265 bp regulatory sequence upstream of the known 5’ end of cDNA. Based on the alignment with plant promoter database, the putative TATA box and transcription start site were located at 106 bp and 120 bp, respectively, from the 5’-end of isolated regulatory region..
Fan, Lir-Wan, and 范鸝婉. "Studies on Anthocyanin Production in Tissue Culture of Dioscorea alata L. var. purpurea M. Pouch." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/51107362206635068000.
Full text東海大學
食品科學系
82
Effects of plant growth regulators on initiation of purple calli from explants of Dioscorea alata L. var. purpurea M. Pouch were studied. Results showed that tuber explants initiated more purple calli than others. The addition of 10 μM 2,4-D and 0.1μM kinetin to the MS medium induced more purple calli than that of other combinations. The fractional factorial experiments were used to investi- gate the effects of cultural conditions on the initiation of purple calli from the explants of yams. Results proved that ranges over the tested, charaoal, type of container, sucrose, nitrogen, phosphate, 2,4-D and kinetin significantly affected the initiation of calli. From the results, a response surface methodology was used to search for the optimum composition of media. The 2,4-D affected very significantly and sucrose affected significantly the initiation of purple calli. The tuber explants of yams were cultured on MF-1 basal medium under different lightings. Results showed that the degree of purple callusing under the sun light was the highest. The optimum temperature for culturing explants was 23.6 ℃. The absorption spectrum of pigments from tubers and purple calli was similar to each other at various pH''s. The number of absorption peaks changed from one to two with the increase of pH. The change of color was from red to violet to blue. Consequently, the pigments of purple calli were tentatively identified as anthocyanins. The retention of anthocyanins extracted from purple calli was 91.8 % after 60 minutes at 95 ℃. The O. D. value was 0.148 for 100 ml 0.1 % HCl-CH3COH extracted from 1 g fresh purple calli. It was 2.11 times to that of tubers. Thus, it is possible to produce anthocyanins by the tissue culture from yams.
Liu, Lien-Shum, and 劉蓮順. "Studies on the purification and properties of polyphenol oxidase from Darsan yam tubers (Dioscorea alata L.)." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/91166130407936681432.
Full text國立嘉義大學
食品科學系碩士班
90
The properties of polyphenol oxidase were studied in this thesis. First of all, polyphenol oxidase (PPO) was isolated and purified from acetone-pretreated Darsan yam powder by salting, ionic exchange and gel chromatography. Subjecting to 5 - 12.5 % gradient polyacrylamide gel electrophoresis, PPO was shown to consist of three subunits with molecular weight 66.9, 86.0 and 91.6 KDa, respectively. Upon testing with 13 different phenolic substrates including monophenolic, diphenolic, and triphenolic compounds such as p-cresol, L-DOPA, and pyrogallol et al., only o-diphenolic compound exhibited enzymatically active to PPO while mono- and triphenolic compounds being inactive. The optimal condition for PPO reacting with L-DOPA was pH 6.5-6.8 at 40 oC or pH 5.0-8.0 at 30 oC. Under this condition, kinetic studies showed that the Km value for L-DOPA and pyrocatechol was 4.3 mM and 1.6 mM, respectively. Both synthetic and natural inhibitants were applied to inhibit PPO activity. It showed that the activity of PPO was inhibited effectively in the presence of salts, organic acids, metallic chelating compounds, aromatic acids, and reducing agents at limited concentration; for instance, DEDTC (0.1 mM), thiourea (5.1 mM),β-mecarptoethanol (3.5 mM), dithiothreital (1.1 mM), Na2S2O5 (1.9 mM), NaHSO3 (2.7 mM), and ascorbic acid (0.08 mM). Interestingly, the natural antioxidant such as 4-hexylresorcinol, kojic acid, and nordihydroguaiaretic acid exhibited apparent inhibition on PPO activity suggesting that natural inhibitants, particularly 4-hexylresorcinol, kojic acid, and nordihydroguaiaretic acid were potential agents for lessoning yam’s browning.
Tseng, Ching-Yuan, and 曾慶元. "Production of Anthocyanins by Different Lines of Dioscorea alata L. var. purpurea M. Pouch Tissue Cultures." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/97142064978122331096.
Full text東海大學
食品科學系
88
The initiation, growth and subculturing of calli from tuber explants of different lines of Dioscorea alata L. var. purpurea M. Pouch were studied. The stability and quality of the pigments in the tuber explants and the initiated calli were also investigated. The addition of 30μM 2,4-D induced more calli than other combinations from the tubers of different lines of Dioscorea alata L. var. purpurea M. Pouch. The addition of kinetin or BA did not significantly affect the percentage or the degree of callusing. The addition of 1.01﹪sucrose to the MF-1 media initiated the highest percentage or the degree of callusing. However, adding GA3 to the MF-1 media did inhibit the initiation and growth and subculturing of calli. Different basic media such as Heller, B-5, WPM, and White did not initiate calli. The MS or its modified one, the MF-1 did initiate calli, however, the calli became brown after subculturing. The absorption spectrums of anthocyanins from different lines of Dioscorea alata L. var. purpurea M. Pouch and at various pH were similar to one another. With the increase of pH, the number of absorption peaks increased from one to two. The change of color was from yellow-red to red to red-violet to violet and to blue-violet. After the tuber anthocyanins were heated under 95 ℃ for 60 minutes, its retention was 91%. For the anthocyanins from the calli the retention was 80% . The anthocyanins from tuber and calli showed good UV stability with the retention of 85% .
Yu, Pei-Ching, and 余珮菁. "Effects of yam (Dioscorea alata L.) mucoploysaccharide on human skin fibroblasts proliferation, Migration, and extracellular matrix production." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/60458365445831493589.
Full text國立臺灣海洋大學
食品科學系
94
The purpose of this study is to explore the effects of yam mucopolysaccharide from Dioscorea alata L. on wound healing. The thesis includes three parts : 1. The effects of yam mucopolysaccharide on human skin fibroblasts proliferation in vitro. 2. The effects of yam mucopolysaccharide on human skin fibroblasts migration in vitro. 3. The effects of yam mucopolysaccharide on the extracellular matrices production by the fibroblasts in vitro. The results obtained might shed the light of the effects of yam mucopolysaccharide on skin wound healing. The results show that yam mucopolysaccharide enhanced human skin fibroblasts proliferation. The higher the concentrations of yam mucopolysaccharide (ranged between 1.56~25 μg/ ml) in 10% serum medium, the better the results on the skin fibroblasts proliferation. The effects of yam mucopolysaccharide on fibroblasts proliferation are more significant for the skin fibroblasts cultured in 1% serum medium at concentrations range between 0.39~200μg/ ml. The enhancement is dose-dependent between 0.39~100μg/ ml on 1% serum medium. The optimal concentration is 100μg/ ml. Yam mucopolysaccharide can also promote migration of human skin fibroblasts. The cells in 200 × times microscopic fields were counted. The beneficial effect of yam mucopolysaccharide on skin fibroblasts migration was dose-dependent. The effects of yam mucopolysaccharide on the fibroblasts migration is significantly different from the control when concentrations are 6.25 μg/ ml and 50 μg/ ml. The results of the effects of yam mucopolysaccharide on the extracellular matrices excretion by the fibroblasts, showed that yam mucopolysaccharide facilitated fibroblasts to secrete either collagen or fibronectin. At a concentration of 12.5μg/ ml of yam mucopolysaccharide, the collagen secretion by the skin fibroblasts is significantly higher than the control. So as the enhancement on the secretion of fibronectin at the slightly higher concentrations (over 12.5μg/ ml).
Hsu, Tien-Ken, and 徐添根. "Environmental Conditions Affecting the Anthocyanin Production by Tissue Culture of Dioscorea alata L. var. purpurea M. Pouch." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/93471007754327593052.
Full text東海大學
食品科學系
83
The explants illuminated under blue light、sun light、green light and egg and white induced more purple calli than those irradiated under other light sources. The explants irradiated under blue light induced the most purple calli among all treatments after 4 week culturing. While the explants irradiated under UV light only induced a few calli and the calli turned brown after 2 week culturing. The addition of 1 μM 、3μM and 5 μM of concentration of GA3 to the MF-1 media did inhibit the degree of callusing of tuber explants. The purple calli subcultured to the MF-1 media containing GA3 induced the growth of white calli while the original purple calli turned brown and died. The effects of concentration of agar on the degree of callusing initiated by tuber explants of Dioscorea alata were also studied. The results proved that agar concentration (w/v) of 0.6 % and 0.8 % induced more calli than those of 0.4 % and 1.0%. The explants treated by pressures of 1000 atm and higher did not initiate calli. The tuber explants treated by 500 atm did initiate calli but the degree of callusing was lower than those without pressure treatments. The tuber explants and calli initiated on MF-1 media by these explants contained two major anthocyanins. One of these is the alatanin C. The anthocyanins of tuber and calli are cyanidin derivatives substituted at position 3 with sugars.
Liang, Yuan-ching, and 梁元菁. "The Preliminary Study of β-Amylase Activity of Dioscorea alata L. var. purpurea M. Pouch and Thermostable-Amylase." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/30350524559228478519.
Full text東海大學
食品科學系
89
There were two parts in this research. The part one was to study the β-amylase activity from Dioscorea alata L. var. purpurea M. Pouch and part two was to study the thermostable β-amylase activity in trans- genic potatos. In part one, it was difficult to purify β-amylase because the crude extract contained sticky substances. After sequentially adding 2% cetylpyridinium and methanol, we were successful to remove the sticky substances. The pH and temperature optima for theβ-amylase activities were pH 6.0 and 60 ℃; the Km and Vmax values were 1.786 % and 357.1 μmole / μL / min separately. The β-amylase was specifically activated by Zn2+ , PMSF and EDTA, but was strongly inhibited by urea. The catalytic efficiency of β-amylase was siguificautly affected by using different substrates. In part two, characteristics of the original thermostable β-amylase expressed in E. coli BL21 was investigated. The temperature optium for this thermostable β-amylase activity was 60 ℃, the Km and Vmax values were 3.2% and 137.0 μmole / μL / min separately. Several transgenic potato lines conferred with thermostable β-amylase gene were obtained. In order to confirm the successful transformation and expression of β-amylase in potatos, a method to determine thermostable β-amylase activies was established. This included dialysis of crudeβ-amylase extract from transgenic potatos for 4 hrs followed by heating under 60 ℃ for 20 mins to denature the endogenousβ-amylase. Using this method to assay all available transgenic potato lines, only ptAmy-sp 1E、ptAmy 2A、ptAmy 5B and ptAmy 7F showed β-amylase activities .
Chang, Shan-Yu, and 張珊瑜. "Dioscorea alata L. reverses renal interstitial cellular fibrosis by regulating Smad- and epithelial-mesenchymal transition related signaling pathway." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/4udqem.
Full text中華醫事科技大學
生物醫學研究所
98
Renal interstitial fibrosis (RIF) is one of the major complications of diabetic nephropathy and the pathology of RIF consists of accumulation of extracellular matrix protein, proliferation of fibroblasts, and epithelial-to-mesenchymal transition (EMT) that leading to renal fibrosis and end-stage renal disease. Transforming growth factor beta1 (TGF-β1) has been implicated as an inducer of cell proliferation and EMT. It is also known as a potent fibrogenic growth factor in renal fibrosis. Recent studies suggest that yam, an agricultural and medicinal plant, is an important herb in Chinese medicine widely used for the treatment of clinical diabetes mellitus. However, the molecular mechanism of Dioscorea alata (DA) on antagonizing renal interstitial fibrosis has never been fully investigated. Thus, this study aims to investigate the modulatory effect of water extract of DA in NRK-49F cells (a rat fibroblasts cell line) under renal fibrosis model, which was induced by β-hydroxybutyrate (β-HB). Western blotting was used to examine protein expression in TGF-β-related signal proteins (type I and type II TGF-β receptor, Smads2/3, pSmad2/3, Smads4, Smads7) and EMT marker (E-cadherin, α-SMA, MMP-2). In addition, Enzyme-linked immunosorbent assay was used to analyze levels of bioactive TGF-β and fibronectin in the culture media. Expression of Fibronectin and transcription factor Snail, a transcription factor that modulates EMT, was also assessed by immunofluorescence staining. DA extract inhibited β-HB-induced expression of fibronectin in NRK-49F cells (P<0.05) concomitantly with dose-dependent inhibition of Smad2/3, pSmad2/3, Smad4. However, Smad7 was significant increased by DA extract. Mesenchymal marker (α-SMA and MMP-2) was significantly decreased and epithelial marker (E-cadherin) was increased by DA extract. These results suggest that DA extract might down-regulate TGF-β/Smad and modulate EMT. In conclusion, we proposed that DA extract might act as a novel renal fibrosis antagonist for treating diabetic nephropathy.
張宏任. "Physicochemical properties and antioxidant activity of land race of yam (dioscorea alata L.) affected by different package and solution treatmant." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/95022924668864621647.
Full textSu, Ting-Ya, and 蘇莛雅. "The effects of Dioscorea alata L. Var. purpurea (M.) Pouch on learning,memory ability and antioxidant status in senescence accelerated mice." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/72207541276191336269.
Full text靜宜大學
食品營養研究所
92
Yam has been used as a tonic agent for centuries in China. Many chemical compounds in yam, such as polyphenol, mucin, diosgenin and dioscorin, have been demonstrated to have healthy effects due to the antioxidant activity. The aim of this study was to evaluate the effects of yam tuber material ( Dioscorea alata L. Var. purpurea (M.) Pouch.) on the learning and memory ability and the antioxidant status of male senescence accelerated mice (SAMP8). In experiment 1, the mice were fed with three different diets for 12 weeks; a casein diet (control group) and either a casein diet supplemented with 10% lyophilized or with hot-air dried yam. Results showed the mice fed with the diet containing yam had significantly better learning and memory ability, and lower brain β-amyloid accumulations than the control group. The malondialdehyde (MDA) concentration of the hippocampus and the monoamine oxidase-B (MAO-B) activity of brain in the group fed lyophilized yam were significantly lower than the control and also the group fed a diet containing hot-air dried yam, whereas the spongy degeneration and the lipofuscin percentage tended to be lower but not significantly different. In experiment 2, the mice were fed with either a casein diet (control group) or a casein diet supplemented with 10%, 20% or 40% lyophilized yam for 12 weeks. Results of passive and active shuttle avoidance tests showed the mice fed with the diet containing 20% and 40% lyophilized yam had significantly better learning and memory ability than the control and 10% yam diet groups. The MDA concentration of the hippocampus and the brain β-amyloid accumulations in the three groups fed with yam were significantly lower than the control group, whereas no differences were found among three yam diet groups. The total thiol concentration and superoxide dismutase activity of 40 % yam diet group were significantly higher than the control group, whereas the brain MAO-B activity and spongy degeneration were lower, and the lipofuscin percentage showed no significant differences. In conclusion, we suggested that the lyophilized yam was more effective than hot-air dried yam in reducing the the deterioration in the learning and memory ability, lipid peroxidation, MAO-B activity and brain pathological changes in mice, and the effects showed dose-dependent.
Ling-Tiao and 洪菱窕. "Effects of Dioscorea alata L. cv. Tainung No. 2 on lumbar, femur and on gut function in ovariectomized female Balb/c mice." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/34740750868887133858.
Full text中山醫學大學
營養學研究所
94
The main purpose of this study was to investigate the effects of Dioscorea alata L. cv. Tainung No. 2 on lumbar and femur bone density, and on gut function in ovariectomized female Balb/c mice. Mice were sham-operated or ovariectomized (OVX) at age of 8 weeks and were fed experimental diets after 3 days. Sham-operated mice (sham) were fed control diet (AIN-93G with corn oil) while OVX mice were randomly allocated into OVX (control diet), E2 (2 mg 17 beta-Estradiol /100 g diet), yam (63 g yam powder/100 g diet) or genistein (200 mg/100 g diet) group. After 12 wk of experiment, mice were decapitalized. Blood, femur, lumbar bones and cecal contents were collected for further analyses. There was no significant difference in food efficiency between groups. Supplementation of E2 completely restored the mineral density (g/cm2) of lumbar and femur bones, respectively, to the level of sham group. Mineral density of lumbar bone and femur, calcium to ash ratio, and calcium content of femur and concentration of serum calcium were restored by both yam and genistein to the levels of sham group. Dry weight and ash content of lumbar bones of yam group tended to increase as compared to the OVX group. The fecal weight and moisture, short chain fatty acid concentrations of cecal content and its daily fecal output were the greatest in mice fed the yam diet. In summary, Tainung No. 2 yam that is well-fermented in the large bowel could effectively delay the postmenopausal bone loss.
Tang, Chian-Wen, and 唐千雯. "Effects of methionine, vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 on testicular/renal antioxidative defense system and histology in adult rats." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/90144187296063905013.
Full text國立成功大學
生物學系碩博士班
92
Homocysteine (Hcy) is a sulfur-containing amino acid whose metabolism stands at the intersection of two pathways including remethylation to methionine (Met) which requires folate and vitamin B12, and transsulfuration to cystathionine which requires vitamin B6.Hyperhomocysteinemia (HHcy) arises from impairment of Hcy metabolism resulting from the deficiency of vitamin B6, B12 or folic acid and has been shown to induce oxidative stress. Studies showed that HHcy treated with vitamin B6、B12 or folic acid could effectively lower plasma Hcy levels. Recently, Hcy has been found to production of reactive oxygen species (ROS) leading to oxidative stress that induce was reported to damage the polyunsaturated fatty acids (PUFA) on the cell membrane, causing the impairment of cellular functions. Studies also showed that HHcy was associated with renal diseases including stages of renal dialysis, renal failure and end-stage renal disease. Testicular membranes are rich in PUFA and highly susceptible to oxidative stress which is implicated in male infertility. In our previous study, we found that Dioscorea alata L. cv. Tainong 2 could decrease plasma Hcy concentration. The present work was undertaken to investigate the oxidative, antioxidative indicators and histology of testis and kidney in HHcy rats supplemented with Met, Met plus vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 simultaneously. HHcy was induced by i.p injection of Met at dose 300 mg/KgBW daily for 8 weeks. Oxidative (Hcy, ROS, MDA) and antioxidative (CAT, SOD, GSH, GSSG, GPx and GR) indicators, and histology of HHcy rats were investigated. Results of oxidative indicators showed that Met group significantly increased Hcy and MDA levels in plasma (p<0.01), ROS and MDA levels in the testis and kidney compare to the control (p<0.01). Vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 significantly decreased Hcy and MDA levels in plasma (p<0.01), folic acid or Dioscorea alata L. cv. Tainong 2 significantly decreased testicular ROS levels (p<0.01), folic acid significantly decreased but Dioscorea alata L. cv. Tainong 2 significantly increased renal ROS levels (p<0.01), vitamin B12 or folic acid significantly decreased testicular MDA levels (p<0.01), vitamin B6, B12 or Dioscorea alata L. cv. Tainong 2 significantly decreased renal MDA levels (p<0.01). Histological examinations showed that Met group had rare of spermatogenic cells and spermatozoa in the seminiferous tube of testis, over-proliferation of mesangial cell, glomerular extracellular matrix was increased in the kidney. The glomerular mesangium was expanded with hypercellularity and capillary collapse in the kidney of the Met group. Vitamin B6, folic acid or Dioscorea alata L. cv. Tainong 2 reversed the development of spermatogenic cells and spermatogenesis in the testis, glomerular structure in the kidney but except vitamin B12 in the kidney. The antioxidative indicators of our data showed that Met group significantly decreased testicular SOD and increased CAT (p<0.01), significantly decreased renal CAT, GR and increased GPx compare to the control group (p<0.01). Folic acid significantly increased testicular and renal CAT (p<0.01), vitamin B12 or folic acid significantly decreased testicular GSH and GSSG levels (p<0.01), vitamin B6 or B12 significantly decreased but Dioscorea alata L. cv. Tainong 2 significantly increased renal GSH levels (p<0.01), vitamin B12 or folic acid significantly decreased but Dioscorea alata L. cv. Tainong 2 significantly increased renal GSSG levels (p<0.01). Vitamin B12 or folic acid significantly increased testicular GPx (p<0.01), vitamin B12 significantly increased but folic acid significantly decreased renal GPx (p<0.01). Vitamin B12 or Dioscorea alata L. cv. Tainong 2 significantly increased but folic acid could significantly decreased testicular GR (p<0.01);vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 significantly decreased renal GR (p<0.01). In summary, (I) methionine injection intraperitoneally (i.p.) could stably induce high Hcy concentrations for a period of time, (II) intraperitoneally injection of Met could induce oxidative stress in the testis and kidney, (III) vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 could significantly decrease oxidative damage induced by Met in the plasma, testis and kidney, (IV) vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 did not furthur induce antioxidative activity, which might be due to the use up of the antioxidative enzymes for scavenging the ROS induced by the Met. In conclusion, vitamin B6, B12, folic acid or Dioscorea alata L. cv. Tainong 2 could protect testis and kidney against the oxidative stress of HHcy induced by Met in this study.
Lu, Fun-Chi, and 呂芳舉. "Study on Arbuscular Mycorrhizal Fungi (AMF) Inoculation on the Growth and Development, Tuber Weight, Allantoin Content and Antioxidant Ability in Yam (Dioscorea alata L.) Cultivated in Taiwan." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/98230614425969659146.
Full text國立屏東科技大學
農園生產系所
104
The symbiotic association between arbuscular mycorrhizal fungi (AMF) and the roots of plants is widespread in the natural environment. AMF benefit their host plant principally by increasing the uptake of macronutrients and some micronutrients, resistance to soil pathogens, tolerance to salinity, heavy metals, and drought stress; maintenance of soil aggregate stability and influence the secondary metabolism levels of plants. The yam (Dioscorea spp.) tubers are edible, medicinal, and used as health foods, they have received considerable attention among the medicinal plants. Yam tubers can produce considerable amounts of antioxidant namely, polyphenols, flavonoids and anthocyanins. They also contained high levels of allantoin that is playing an important role in present skin inflammation and ulcers of the human body; thus, the secondary metabolites that exist in yam tubers have value for development and utilization in medicine practice and health care. In this study, five commercial species and line of yams (Dioscorea alata L.) were inoculated with six species of AMF, Glomus clarum, G. etunicatum, G. fasciculatum, Gigaspora sp., G. mosseae, and Acaulospora sp., in field cultivation conditions to investigate the influence of AMF inoculation on mycorrhizae formation rates, physiological components of leaves, nutrition analysis, tuber weights, secondary metabolite content and antioxidant ability in yam tubers. The results showed that all six AMF species were able to form mycorrhizae relationship with the host yams, and mycorrhizae formation rates ranged from 63.33% to 90%, indicating that these AMF present high compatibility with the host yams. In this research, the majority of the yam plants with AMF inoculation had substantially higher chlorophyll content as well as soluble carbohydrate and protein compared with those non-inoculation control group. The amount of chlorophyll content in yam leaves inoculated with AMF the control group were 1.93/1.73, 2.30 /2.10, 2.12/1.86, 1.93/1.62 and 1.93 /1.66 mg/g for Tainung No. 1, Tainung No. 2, Zihyuxieshu , Ercih and Tainung No. 5 respectively; and the maximum increased amount of both the soluble protein and carbohydrate were 76.55/60.83, 98.99/73.70, 147.33/120.80, 74.06/51.37 and 92.91/ 59.41 mg/g; 140.75/105.75, 104.62/81.73, 129.88/103.54, 158.13/110.28 and 157.90/134.27 mg/g respectively. The root colonization by AMF enabled the leaves of host yam presented high concentrations of nitrogen and potassium than those of the controls. However, yams inoculated with six of AMF for six weeks did not increase the content of soluble phosphorus. Our study showed that AMF inoculation can improve the tuber weights of five yams. G. etunicatum inoculation treatment increased the yam tuber weights by 39%, 35%, 20%, 56%, and 40% for Tainung No. 1, Tainung No. 2, Ercih, Zihyuxieshu, and Tainung No. 5 compared with the control group, respectively. The content of secondary metabolites, such as polyphenols, flavonoids, and anthocyanin, was significantly increased by the AMF treatment in tuber flesh and peel of the tested yam. Specifically, the maximums exchange of secondary metabolite contents increased to 40%, 42%, and 106% for polyphenols, flavonoids and anthocyanin respectively in the tuber fresh. Moreover, those ample functional ingredients, involving polyphenols, flavonoids and anthocyanins can be extracted from the peel of tuber, thereby increasing the potency and utilization of yam tubers. The AMF inoculation boost the secondary metabolites antioxidant compounds, thus enhancing the antioxidant ability of yams. The allantoin analysis experiments showed that the yam tuber peels was with higher allantoin content than the yam tuber flesh. The peels of per gram of tuber are 159%, 209%, 64%, 99% and 97% higher than those of the fresh of Tainung No. 1, Tainung No. 2, Ercih, Zihyuxieshu, and Tainung No. 5, respectively. Compared with the non-inoculated yams, the allantoin levels in tubers presented that in both the fresh and peels were 10.7%, 8.3%, 7.6%, 3.2% and 12.3%; 15.4%, 18.0%, 15.2%, 4.0% and 22.5% for Tainung No. 1, Tainung No. 2, Ercih, Zihyuxieshu, and Tainung No. 5 respectively. In this study, the data showed that Tainung No. 1, Tainung No. 2 and Ercih three white flesh yams species treated with G. etunicatum and G. mosseae enhanced the yam tuber yield and polyphenols and flavonoids content. The two species of purple yams, Zihyuxieshu and Tainung No. 5, treated with G. etunicatum and Gigaspora sp. enhance the yam tuber yield and polyphenols, flavonoids and anthocyanins content. The inoculation of yams with AMF can expedite plant growth and increase the tuber weight, antioxidants, allantoin content of secondary metabolites in tubers. Therefore, AMF can be used as a microbial fertilizer and developed for yam cultivation and production.
Yu-Ju and 楊玉如. "Effects of Taiwanese yam (Dioscorea alata L. cv. Tainung No. 2) and its ethyl-acetate extract on the morphology of intestinal mucosa cells in ovariectomized female Balb/c mice." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/43986197604669221198.
Full text中山醫學大學
營養學研究所
96
The main purpose of this study was to investigate the effects of Dioscorea alata L. cv. Tainung No. 2 and its ethyl-acetate extract on the morphology of villi and proliferation of intestinal mucosa cells in ovariectomized female Balb/c mice. Mice were sham-operated or ovariectomized (OVX) at age of 8 weeks and were fed experimental diets after 3 days. Sham-operated mice (sham) were fed control diet (AIN-93G with corn oil) while OVX mice were randomly allocated into OVX (control diet), yam (63 g yam powder/100 g diet), yam extract (2 mg/g diet), genistein (200 mg/100 g diet), E2 (2 mg 17β-Estradiol /100 g diet) group. Animals were fed ad libitum fro 12 wk. Eighteen h before sacrifice, mice were injected with 0.69~0.75 mg 5-bromo-2''-deoxyuridine. The fundus, stomach body, duodenum, jejunum, ileum, cecum and distal colon were dissected and processed for immunohistochemical analyses. OVX reduced the sizes of gastric gland in the stomach body and villous in duodenum. Yam group reversed the OVX effect in the stomach body; while supplement with yam, yam extract, genistein or E2 completely restored the villous morphology in the duodenums to the level of sham group. OVX reduced the thickness of longitudinal and circular muscle in the stomach body, and in the jejunum, respectively, but increased the thickness of the distal colon. Estradiol diet increased the muscular thickness in stomach, duodenum and jejunum. On the other hand, yam diet tended to increase the muscular thickness in the ileum, cecum and distal colon. Yam extract did not exert significant effect in most intestinal region. These results suggest that Tainung No. 2 yam and its ethyl-acetate extracts may beneficially protect mucosa linings in the stomach and duodenum in postmenopausal women.
Yi, Chen Jie, and 陳傑易. "Effect the water extract from of Tainug No1.(TGNl) (Dioscoera alafa L.) and Mingjian (Dioscoera alafa L. var. purpurea M Pouch) on the antioxidant enzyme activities in mouse liver cell and liver cancer cell." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/01874745559893865641.
Full text亞洲大學
生物科技學系碩士班
93
Recently, there is increasing interest in finding natural antioxidants from plants to protect human body against damage due to oxidative stress. The purposes of this study were to evaluate the effects of water extracts from two species of Taiwanese yams, Tainung No.1 (TNG1)(Dioscoera alata L.) and Mingjian (Dioscoera alata L. var. purpurea M. Pouch) on the activities of antioxidant enzymes in the cells. The influences of oxidant agents, tert-Butyihydrogen peroxide (t-BHP) and sodium mtreprusside (SNP), on the activities of antioxidant enzymes were also determined.The results showed that the water extracts from TNG1 and Mingjian could raise the activities of SOD and CAT in mouse liver cell FL83B. The water extract from Mingjian increased the activity of CAT in mouse liver cancer cell Hepa 1-6.In FL83B, the induce of t-BHP increased the activity of GPx When FL83B was incubated with the water extract from TNG1, the CAT and GPx activities increased after the induction of t-BHP. But the addition of the water extract from Mmgjian increased the activity of GPx after the induction of t-BHP In Hepa 1-6, the induce of t-BHP increased the activity Of CAT. When Hepa 1-6 was incubated with the water extract from Mingjian, the CAT activity was also increased FL83B had lower CAT and SOD activities when induced with SNP With the addition of the extract from TNG1, FL83B showed lower CAT and SOD activities after the induction of SNP But with the addition of the extract from Mmgjian, the activity of CAT decreased after the induction of SNP For Hepa 1-6, only Hepa 1-6 incubated with the water extract from Mmgjian showed lower SOD activities after the induction of SN?. After all, yam could increase the activities of antioxidant enzymes When the cells were induced by oxidant agents, the influence of oxidant agents on the activities of antioxidant enzymes might be different because they might involve m differint oxidative pathway.