| [role of the digestive microflora and of the crystalline structure of starch in digestion and dietary efficiency in the chicken. study of tropical tubers]. | the influence of microflora in the utilization of starches, the x ray pattern which was of a or b type, was studied by balances and carcasses analysis with growing axenic or holoxenic chickens, put in isolators. five tropical tubers were used : manihot utilissima and dioscorea dumetorum of a-type, dioscorea cayenensis and alata and canna edulis of b-type. they were introduced in isoenergetic (4,460 kcal/g d.m.) and isoproteic (18 p. 100) diets. the a-type starches are entirely digested (95 p. 10 ... | 1979 | 496174 |
| effect of yam (dioscorea cayenensis) and dasheen (colocassia esculenta) extracts on the kidney of streptozotocin-induced diabetic rats. | streptozotocin-induced diabetic wistar rats were maintained for 4 weeks on a supplement of extracts of yam (dioscorea cayenensis) or dasheen (colocassia esculenta). the activities of malic enzyme, nadp+ isocitrate dehydrogenase, glucose 6-p-dehydrogenase and the transaminases were determined to assess any degree of metabolic alteration caused by diabetic nephropathy. diabetic rats fed normal diet and those fed yam extract, dasheen extract and commercial linamarin respectively lost weight signifi ... | 2001 | 11517735 |
| antifungal steroid saponins from dioscorea cayenensis. | from the rhizomes of dioscorea cayenensis lam.-holl (dioscoreaceae), the new 26- o- beta- d-glucopyranosyl-22-methoxy-3 beta,26-dihydroxy-25( r)-furost-5-en-3- o- alpha- l-rhamnopyranosyl-(1-->4)- alpha- l-rhamnopyranosyl-(1-->4)-[ alpha- l-rhamnopyranosyl-(1-->2)]- beta- d-glucopyranoside ( 1) was isolated together with the known dioscin ( 2) and diosgenin 3- o- alpha- l-rhamnopyranosyl-(1-->4)- alpha- l-rhamnopyranosyl-(1-->4)-[ alpha- l-rhamnopyranosyl-(1-->2)]- beta- d-glucopyranoside ( 3). ... | 2004 | 14765305 |
| a new steroidal saponin from dioscorea cayenensis. | the new 26-o-beta-d-glucopyranosyl-3beta,26-dihydroxy-20,22-seco-25(r)-furost-5-en-20,22-dione-3-o-alpha-l-rhamnopyranosyl-(1-->4)-alpha-l-rhamnopyranosyl-(1-->4)-[alpha-l-rhamnopyranosyl-(1-->2)]-beta-d-glucopyranoside (1), along with the known methyl protodioscin (2), asperoside (3) and prosapogenin a of dioscin (4) were isolated from the rhizomes of dioscorea cayenensis lam.-holl (dioscoreaceae). their structures were established mainly on the basis of 600 mhz 2d-nmr spectral data. 4 exhibite ... | 2004 | 15516762 |
| food processing methods influence the glycaemic indices of some commonly eaten west indian carbohydrate-rich foods. | glycaemic index (gi) values for fourteen commonly eaten carbohydrate-rich foods processed by various methods were determined using ten healthy subjects. the foods studied were round leaf yellow yam (dioscorea cayenensis), negro and lucea yams (dioscorea rotundata), white and sweet yams (dioscorea alata), sweet potato (solanum tuberosum), irish potato (ipomoea batatas), coco yam (xanthosoma spp.), dasheen (colocasia esculenta), pumpkin (cucurbita moschata), breadfruit (artocarpus altilis), green ... | 2006 | 16925852 |
| removal of potassium from tuberous root vegetables by leaching. | to determine analytically the amount of potassium in raw tuberous root vegetables (trv); to estimate the amount of potassium that can be leached from raw trv by soaking in water; and to determine whether the duration of soaking and the cooking method selected affect potassium extraction. | 2006 | 17046614 |
| molecular marker based taxonomy and phylogeny of guinea yam (dioscorea rotundata - d. cayenensis). | four different molecular techniques were used to assess relationships among 21 accessions of guinea yam (dioscorea rotundata and dioscorea cayenensis) and 21 accessions belonging to seven putative progenitor species. random amplified polymorphic dna (rapd) and microsatellite-primed pcr (mp-pcr) analysis yielded 246 informative characters that were transformed into a matrix of pairwise distances and analyzed by neighbor joining or split decomposition. both methods gave congruent results. well-sep ... | 1997 | 18464876 |
| origin and phylogeny of guinea yams as revealed by rflp analysis of chloroplast dna and nuclear ribosomal dna. | the origin and phylogeny of the guinea yams, consisting of the white yam (dioscorea rotundata poir.) and the yellow yam (d. cayenensis lamk.), has been investigated. fourteen cultivars of guinea yams were sampled with 12 accessions from seven wild yam species. a total of 26 accessions were surveyed for restriction fragment length polymorphisms (rflp) in chloroplast dna (cpdna) and nuclear ribosomal dna (rdna) using seven restriction endonucleases and various heterologous probes. chloroplast dna ... | 1992 | 24202749 |
| high genetic diversity, distant phylogenetic relationships and intraspecies recombination events among natural populations of yam mosaic virus: a contribution to understanding potyvirus evolution. | to evaluate the genetic diversity and understand the evolution of yam mosaic virus (ymv), a highly destructive pathogen of yam (dioscorea sp.), sequencing was carried out of the c-terminal part of the replicase (nib), the coat protein (cp) and the 3'-untranslated region (3'-utr) of 27 ymv isolates collected from the three main cultivated species (dioscorea alata, the complex dioscorea cayenensis-dioscorea rotundata and dioscorea trifida). ymv showed the most variable cp relative to eight other p ... | 2000 | 10640564 |
| relationship between the physicochemical properties of starches and the glycemic indices of some jamaican yams (dioscorea spp.). | starch granules from round leaf yellow yam (ry), lucea yam (ly), white yam (wy), and chinese yam (cy) grown in jamaica were isolated and the relationship between starch amylose content, crystallinity, microscopic properties, in vitro digestibility, and the glycemic index (gi) of the tubers was investigated. the results indicate that ry had the highest amylose content (265.30 +/- 0.09 g/kg starch) while cy the lowest (111.44 +/- 0.03 g/kg starch). a corresponding variation in starch digestibility ... | 2008 | 18727011 |
| the interplay between yam (dioscorea sp.) starch botanical source, micromeritics and functionality in paracetamol granules for reconstitution. | a comparative investigation of the interplay between starch botanical source, micromeritics and their functionality in formulated paediatric paracetamol granules for reconstitution was conducted using starches extracted from five local yam (dioscorea spp.) species. significant differences were observed in the physicochemical properties of the different starches studied (p<0.05). the observed differences in paracetamol dissolution correlated well with the physicochemical properties of the starche ... | 2008 | 18423995 |
| isolation and characterization of microsatellites for the yam dioscorea cayenensis (dioscoreaceae) and cross-amplification in d. rotundata. | dioscorea cayenensis and dioscorea rotundata are among the most important yam species for the humid and sub-humid tropics. we isolated nine polymorphic microsatellite markers using a microsatellite-enriched genomic library technique. the nine primer pairs were validated in 22 d. cayenensis accessions, and were tested for transferability in 26 d. rotundata accessions. the number of bands ranged from 2 to 4, with a mean of 3.11. d. cayenensis gave primer polymorphism information content values ran ... | 2014 | 24782090 |
| promiscuous arbuscular mycorrhizal symbiosis of yam (dioscorea spp.), a key staple crop in west africa. | yam (dioscorea spp.) is a tuberous staple food crop of major importance in the sub-saharan savannas of west africa. optimal yields commonly are obtained only in the first year following slash-and-burn in the shifting cultivation systems. it appears that the yield decline in subsequent years is not merely caused by soil nutrient depletion but might be due to a loss of the beneficial soil microflora, including arbuscular mycorrhizal fungi (amf), associated with tropical "tree-aspect" savannas and ... | 2009 | 19343374 |
| use of cpssrs for the characterisation of yam phylogeny in benin. | the dioscorea cayenensis - dioscorea rotundata species complex is the most widely cultivated yam in west africa. this species complex has been described as deriving from wild yams belonging to the enanthiophyllum section through domestication by african farmers. to study patterns of yam evolution and to establish phylogenetic relationships existing between wild and cultivated species sampled in benin, we investigated changes in chloroplast dna simple sequence repeats (cpssr) in 148 yam accession ... | 2005 | 16094435 |
| high-quality draft whole-genome sequences of three strains of enterobacter isolated from jamaican dioscorea cayenensis (yellow yam). | here we report the whole-genome sequences of three endophytic bacteria, enterobacter sp. strain dc1, enterobacter sp. strain dc3, and enterobacter sp. strain dc4, from root tubers of the yellow yam plant, dioscorea cayenensis. preliminary analyses suggest that the genomes of the three bacteria contain genes involved in acetoin and indole-3-acetic acid metabolism. | 2014 | 24625871 |
| genetic structure and diversity in the dioscorea cayenensis/d. rotundata complex revealed by morphological and isozyme markers. | of the 600 known yam species, only 10 are utilized as food, and the dioscorea cayenensis/d. rotundata species complex is among the most cultivated. in brazil, these species are commercially cultivated in the northeast region and are cultivated in the south and southeast regions as subsistence crops by traditional agriculturists. this study aimed to evaluate the genetic diversity of 21 local varieties of d. cayenensis and 2 d. rotundata accessions using 7 isozymic loci and 24 morphological marker ... | 2014 | 24535869 |
| characterizing genotypic variation in biochemical composition, anti-nutritional and mineral bioavailability of some nigerian yam (dioscorea spp.) land races. | the aim of this study was to characterize 43 genotypes from five yam species [dioscorea rotundata (poir), dioscorea alata (linn), dioscorea bulbifera (linn), dioscorea cayenensis (lam) and dioscorea dumetorum (kunith) pax] which are major land races in nigeria in terms of their chemical composition, nutritional, anti-nutritional and mineral bioavailability. findings showed that there was genotypic variation in terms of chemical composition, mineral profile and bioavailability of the minerals amo ... | 2018 | 29358812 |
| effects of processing methods on nutrient and antinutrient composition of yellow yam (dioscorea cayenensis) products. | there is dearth of documented information on nutrient retention of dioscorea cayenensis products. this study was carried out to evaluate effects of processing methods on nutrient and antinutrient retention of yellow yam products. fresh dioscorea cayenensis tubers were purchased from bodija market in ibadan, peeled, cut into small pieces, divided into nine portions. one portion was treated as raw sample, and others processed into local delicacies. all nine samples were analysed for proximate, min ... | 2018 | 28867088 |
| nutrient and antinutrient composition of yellow yam (dioscorea cayenensis) products. | the data presented in this article are related to research article titled "effects of processing methods on nutrient and antinutrient composition of yellow yam (dioscorea cayenensis) products" (adepoju et al., 2016) [1]. this article documented information on nutrient and antinutrient composition as well as nutrient retention of dioscorea cayenensis products. fresh dioscorea cayenensis tubers obtained from bodija market were prepared into raw sample and local delicacies and analysed for proximat ... | 2017 | 28280763 |
| the genome of african yam (dioscorea cayenensis-rotundata complex) hosts endogenous sequences from four distinct badnavirus species. | several endogenous viral elements (eves) have been identified in plant genomes, including endogenous pararetroviruses (eprvs). here, we report the first characterization of eprv sequences in the genome of african yam of the dioscorea cayenensis-rotundata complex. we propose that these sequences should be termed 'endogenous dioscorea bacilliform viruses' (edbvs). molecular characterization of edbvs shows that they constitute sequences originating from various parts of badnavirus genomes, resultin ... | 2014 | 24605894 |
| the prevalence of badnaviruses in west african yams (dioscorea cayenensis-rotundata) and evidence of endogenous pararetrovirus sequences in their genomes. | yam (dioscorea spp.) is an important vegetatively-propagated staple crop in west africa. viruses are pervasive in yam worldwide, decreasing growth and yield, as well as hindering the international movement of germplasm. badnaviruses have been reported to be the most prevalent in yam, and genomes of some other badnaviruses are known to be integrated in their host plant species. however, it was not clear if a similar scenario occurs in dioscorea yam. this study was conducted to verify the prevalen ... | 2014 | 24457074 |
| functional, thermal and molecular behaviours of ozone-oxidised cocoyam and yam starches. | ozone-oxidised starches were prepared from the native starches isolated from white and red cocoyam, and white and yellow yam cultivars. the native and oxidised starches were evaluated for functional, thermal and molecular properties. the correlations between the amount of reacted ozone and carbonyl and carboxyl contents of the starches were positive, as ozone generation time (ogt) increased. significant differences were obtained in terms of swelling power, solubility, pasting properties and text ... | 2013 | 23790933 |
| two spirostan steroid glycoside fatty esters from dioscorea cayenensis. | two new fatty acid-spirostan steroid glycoside esters, progenin iii palmitate (1) and progenin iii linoleate (2), were isolated from the meoh extract of dioscorea cayenensis rhizomes. the extract also yielded seven previously known spirostan and furostan steroid glycosides (3-9). the structures of the new compounds were established as (25r)-spirost-5-en-3beta-yl o-alpha-l-rhamnopyranosyl-(1 --> 2)-[6-o-palmitoyl]-o-beta-d-glucopyranoside (1) and (25r)-spirost-5-en-3beta-yl o-alpha-l-rhamnopyrano ... | 2013 | 23678801 |
| effect of bauxite mineralized soil on residual metal levels in some post harvest food crops in jamaica. | the concentrations of nine residual metals in some jamaican foods were determined using inductively coupled plasma mass spectrometry technique. cadmium concentration was highest in yellow yam (0.21 mg/kg). sweet potato had the highest concentrations of lead (0.31 mg/kg), arsenic (0.70 mg/kg) and mercury (0.35 mg/kg). samples from grove place exceeded the regulatory limits of 0.1 mg/kg for cadmium, lead and arsenic and 0.05 mg/kg for mercury. significant correlations were found between soil and a ... | 2012 | 22864633 |
| effects of storage conditions on sprouting of microtubers of yam (dioscorea cayenensis-d. rotundata complex). | the control of field tuber dormancy in the yam (dioscorea cayenensis-d. rotundata complex) is poorly understood. although studies have examined single environmental factors and chemical treatments that might prolong tuber dormancy and storage, only a few were focused on further tuber sprouting. the present study concerns microtubers obtained by in vitro culture. when microtubers were harvested (after 9 months of culture) and directly transferred on a new medium without hormones, the tubers rapid ... | 2010 | 20176333 |
| in vitro availability of some essential minerals in commonly eaten processed and unprocessed caribbean tuber crops. | the levels of three essential minerals ca, fe and mg and the extent of their availability were assessed in four commonly eaten caribbean tuber crops [dasheen (xanthosoma spp.), irish potato (solanum tuberosum), sweet potato (ipomoea batatas) and yellow yam (dioscorea cayenensis)] in their processed and unprocessed states. calcium was highest in cooked dasheen (5150+/-50 mg/kg) while magnesium was highest in uncooked irish potato (3600+/-200 mg/kg). there was no significant loss of calcium from t ... | 2007 | 16758116 |
| isolation and characterisation of cdna clones representing the genes encoding the major tuber storage protein (dioscorin) of yam (dioscorea cayenensis lam.). | cdna clones encoding dioscorins, the major tuber storage proteins (m(r) 32,000) of yam (dioscorea cayenesis) have been isolated. two classes of clone (a and b, based on hybrid release translation product sizes and nucleotide sequence differences) which are 84.1% similar in their protein coding regions, were identified. the protein encoded by the open reading frame of the class a cdna insert is of m(r) 30,015. the difference in observed and calculated molecular mass might be attributed to glycosy ... | 1995 | 7632909 |
| first controlled progenies checked by isozymic markers in cultivated yams dioscorea cayenensis-rotundata. | as tested progeny have never been obtained, breeding studies on african yams (dioscorea cayenensisrotundata) are scarce. we report here the first progenies checked by isoenzyme markers. this was made possible by the choice of well-known genitors [one male (cv zrezrou) and three females (cvs 'sopéré', 'dahomey' and 'c 20')] and special hybridization conditions. six enzymatic systems [esterase (est), isocitrate dehydrogenase (icd), malate dehydrogenase (mdh), 6-phosphogluconate dehydrogenase (6pgd ... | 1994 | 24186255 |
| variability, repeatability, character correlation and path coefficient analyses in yellow yam. | phenotypic variances, genetic coefficients of variation, repeatability, expected genetic advance, correlation coefficients and path coefficients were estimated for seven agronomic traits in yellow yam. plant leafiness, leaf virus infection, number of tubers per hill and tuber yield showed higher expected genetic advances associated with higher repeatability. positive and highly significant correlations of tuber yield with plant leafiness, shoot height and vine dry weight were observed. correlati ... | 1984 | 24253715 |