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1

The origin of Manihot esculenta Crantz (Euphorbiaceae)  

Microsoft Academic Search

Contrary to views that cassava (Manihot esculenta) is only known in cultivation an argument is made that wild accessions of the species grow over much of the American neotropics, in Brazil, Bolivia, Peru, Venezuela, Guyana, and Surinam. Three subspecies are recognized. M. esculenta subsp. esculenta is the domesticate and includes all cultivars known in cultivation. The wild M. esculenta subsp.

Antonio C. Allem

1994-01-01

2

Evidence on the origin of cassava: Phylogeography of Manihot esculenta  

Microsoft Academic Search

Cassava (Manihot esculenta subsp. esculenta )i s a staple crop with great economic importance worldwide, yet its evolutionary and geographical origins have remained unresolved and controversial. We have investigated this crop's domestica- tion in a phylogeographic study based on the single-copy nuclear gene glyceraldehyde 3-phosphate dehydrogenase (G3pdh). The G3pdh locus provides high levels of noncoding sequence variation in cassava and

KENNETH M. OLSEN; BARBARA A. SCHAAL

1999-01-01

3

Microsatellites in Cassava (Manihot esculenta Crantz): discovery, inheritance and variability  

Microsoft Academic Search

Fourteen microsatellites containing GA-repeats were isolated and characterized in cassava (Manihot esculenta Crantz, Euphorbiaceae). Microsatellite heterozygosity (h) was estimated in 48 accessions using (32P)-end-labeled primers and in more than 500 accessions using fluorescence-based genotyping. Heterozygosity values ranged from\\u000a 0.00 to 0.88 and the number of alleles detected varied from 1 to 15. The reproducibility of allele sizing was also assessed

P. P. Chavarriaga-Aguirre; M. M. Maya; M. W. Bonierbale; S. Kresovich; M. A. Fregene; J. Tohme; G. Kochert

1998-01-01

4

Evidence on the origin of cassava: Phylogeography of Manihot esculenta  

PubMed Central

Cassava (Manihot esculenta subsp. esculenta) is a staple crop with great economic importance worldwide, yet its evolutionary and geographical origins have remained unresolved and controversial. We have investigated this crop’s domestication in a phylogeographic study based on the single-copy nuclear gene glyceraldehyde 3-phosphate dehydrogenase (G3pdh). The G3pdh locus provides high levels of noncoding sequence variation in cassava and its wild relatives, with 28 haplotypes identified among 212 individuals (424 alleles) examined. These data represent one of the first uses of a single-copy nuclear gene in a plant phylogeographic study and yield several important insights into cassava’s evolutionary origin: (i) cassava was likely domesticated from wild M. esculenta populations along the southern border of the Amazon basin; (ii) the crop does not seem to be derived from several progenitor species, as previously proposed; and (iii) cassava does not share haplotypes with Manihot pruinosa, a closely related, potentially hybridizing species. These findings provide the clearest picture to date on cassava’s origin. When considered in a genealogical context, relationships among the G3pdh haplotypes are incongruent with taxonomic boundaries, both within M. esculenta and at the interspecific level; this incongruence is probably a result of lineage sorting among these recently diverged taxa. Although phylogeographic studies in animals have provided many new evolutionary insights, application of phylogeography in plants has been hampered by difficulty in obtaining phylogenetically informative intraspecific variation. This study demonstrates that single-copy nuclear genes can provide a useful source of informative variation in plants.

Olsen, Kenneth M.; Schaal, Barbara A.

1999-01-01

5

Abstracts on Cassava (Manihot esculenta' Crantz). Vol. 12, Numbers 1-3, 1986,  

National Technical Information Service (NTIS)

Presented here are the three volumes of the 1986 edition of CIAT's journal of analytical abstracts on cassava 'Manihot esculenta' Crantz. A total of 654 abstracts are included providing condensed information from journal articles, booklets, mimeographed r...

M. Vargas de West

1986-01-01

6

Microsatellite Variation in Cassava (Manihot esculenta, Euphorbiaceae) and Its Wild Relatives: Further Evidence for a Southern Amazonian Origin of Domestication  

Microsoft Academic Search

Genetic variation at five microsatellite loci was used to investigate the evolutionary and geographical origins of cassava (Manihot esculenta subsp. esculenta) and the population structure of cassava's wild relatives. Two hundred and twelve individuals were sampled, representing 20 crop accessions, 27 populations of cassava's closest wild relative ( M. esculenta subsp. flabellifolia ), and six populations of a potentially hybridizing

Kenneth M. Olsen; Barbara A. Schaal

2001-01-01

7

Optimization of Enzymatic Hydrolysis of Manihot Esculenta Root Starch by Immobilized ?-Amylase Using Response Surface Methodology  

Microsoft Academic Search

Enzymatic hydrolysis of starch from natural sources finds potential application in commercial production of alcoholic beverage and bioethanol. In this study the effect of starch concentration, temperature, time and enzyme concentration were studied and optimized for hydrolysis of cassava (Manihot esculenta) starch powder (of mesh 80\\/120) into glucose syrup by immobilized (using Polyacrylamide gel) ?-amylase using central composite design. The

G. Baskar; C. Muthukumaran; S. Renganathan

2008-01-01

8

Biodiesel production from algal oil using cassava ( Manihot esculenta Crantz) as feedstock  

Microsoft Academic Search

As a potential source of biomass supplies, cassava (Manihot esculenta Crantz) has been studied for bioethanol production, but not for the production of biodiesel. In this study, we used cassava\\u000a hydrolysate as an alternative carbon source for the growth of microalgae (Chlorella protothecoides) which accumulated oil in vivo, with high oil content up to 53% by dry mass under a

Yue Lu; Yan Zhai; Minsheng Liu; Qingyu Wu

2010-01-01

9

Gene-based microsatellites for cassava (Manihot esculenta Crantz): prevalence, polymorphisms, and cross-taxa utility  

Microsoft Academic Search

BACKGROUND: Cassava (Manihot esculenta Crantz), a starchy root crop grown in tropical and subtropical climates, is the sixth most important crop in the world after wheat, rice, maize, potato and barley. The repertoire of simple sequence repeat (SSR) markers for cassava is limited and warrants a need for a larger number of polymorphic SSRs for germplasm characterization and breeding applications.

Adebola AJ Raji; James V Anderson; Olufisayo A Kolade; Chike D Ugwu; Alfred GO Dixon; Ivan L Ingelbrecht

2009-01-01

10

Genetic variation of cassava ( Manihot esculenta Crantz) cultivated by Chibchan Amerindians of Costa Rica  

Microsoft Academic Search

This study focuses on the genetic diversity of the cassava (Manihot esculenta Crantz) grown by the Chibchan Amerindians of Costa Rica. The authors collected cassava in various locations within two Amerindian\\u000a Reserves: Talamanca, inhabited by Cabecares and Bribris, and Coto Brus, inhabited by Guaymi. Through the use of isozyme electrophoretic\\u000a techniques we found variation for six out of nine systems

Maria E. Zaldivar; Oscar J. Rocha; Gabriel Aguilar; Luis Castro; Emilio Castro; Ramiro Barrantes

2004-01-01

11

Cyanide content of cassava ( Manihot esculenta , Euphorbiaceae) cultivars used by Tukanoan Indians in Northwest Amazonia  

Microsoft Academic Search

Cassava (Manihot esculenta) is a cyanide-containing food crop used by many indigenous peoples in Amazonia. Tukanoan Indians in Northwest Amazonia utilize\\u000a both “bitter” and “sweet” cassava cultivars. Those classified as “bitter” are the dietary staple. Analysis of 13 commonly\\u000a used “bitter” cultivars indicates that they are high in cyanide in comparison to values reportedin the literature. The Tukanoan\\u000a practice of

Darna L. Dufour

1988-01-01

12

Mining EST-Derived SSR Markers to Assess Genetic Diversity in Cassava ( Manihot esculenta Crantz)  

Microsoft Academic Search

Cassava (Manihot esculenta Crantz) is a very important staple and industrial crop in tropical and subtropical regions of the world. The paucity of markers\\u000a is a serious limitation in marker-assisted breeding. A total of 35,992 expressed sequence tags (ESTs) from cassava, which\\u000a were clustered in 13,173 unigenes, were used in this study. A total of 1,889 microsatellites were identified, with

Meiling Zou; Zhiqiang Xia; Peng Ling; Yang Zhang; Xin Chen; Zusheng Wei; Weiping Bo; Wenquan Wang

13

Microsatellite variation of cassava ( Manihot esculenta Crantz) in home gardens of Chibchan Amerindians from Costa Rica  

Microsoft Academic Search

We used 13 microsatellite marker loci to determine the genetic diversity of cassava (Manihot esculenta Crantz) grown in home gardens in two Chibchan Amerindian reserves in Costa Rica. We compared the levels of genetic diversity\\u000a in the reserves with that of commercial varieties typically cultivated in Costa Rica. We found high levels of genetic diversity\\u000a among cassava plants. Overall, 12

Oscar J. Rocha; Maria E. Zaldivar; Luis Castro; Emilio Castro; Ramiro Barrantes

2008-01-01

14

Selection for perceptual distinctiveness: Evidence from aguaruna cultivars of Manihot esculenta  

Microsoft Academic Search

This paper presents evidence that cultivars of manioc (Manihot esculenta) have been selected for combinations of characters that allow them to be perceptually distinguished. This mode of selection\\u000a is proposed to explain why cultivars are so variable in perceptually salient taxonomic characters unrelated to the use or\\u000a survival of the plant. This paper reanalyzes published material on manioc and related

James Shilts Boster

1985-01-01

15

In vitro effects of Cassava (Manihot esculenta) leaf extracts on four development stages of Haemonchus contortus.  

PubMed

Three extracts (aqueous, methanolic and dichloromethane) of Manihot esculenta (Cassava) leaf were tested in vitro on four development stages of Haemonchus contortus using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI) and adult worm motility assay (AWM). Compared to the negative control, significant effects (P<0.0001) were observed for the methanolic extract of leaf against larval development (57.6% +/-7.6), with a dose dependent effect. These results suggest that Cassava possess anthelmintic activity against H. contortus. The active principles responsible for the activity could be the terpenoids and condensed tannin compounds present in the leaf. PMID:20638799

Marie-Magdeleine, C; Udino, L; Philibert, L; Bocage, B; Archimede, H

2010-06-26

16

Microevolution in agricultural environments: how a traditional Amerindian farming practice favours heterozygosity in cassava (Manihot esculenta Crantz, Euphorbiaceae)  

Microsoft Academic Search

We demonstrate a novel case of selection for heterozygosity in nature, involving inadvertent human selection on a population of domesticated plants. Amerindian farmers propagate cassava (Manihot esculenta) clonally by cuttings. Seedlings also appear spontaneously in fields, and farmers allow them to grow, later using some for cuttings. These volunteers contribute new genotypes. However, many are inbred, whereas multiplied clones are

Benoit Pujol; Patrice David; Doyle McKey

2005-01-01

17

Construction of a genetic linkage map using simple sequence repeat markers from expressed sequence tags for cassava ( Manihot esculenta Crantz)  

Microsoft Academic Search

Cassava (Manihot esculenta) is an economically important crop that is grown in tropical and sub-tropical regions. Use of molecular technology for genetic\\u000a improvement of cassava has been limited by the lack of a large set of DNA markers and a genetic map. Therefore, the aims here\\u000a were to develop additional simple sequence repeat (SSR) markers from the public expressed sequence

S. Kunkeaw; T. Yoocha; S. Sraphet; A. Boonchanawiwat; O. Boonseng; D. A. Lightfoot; K. Triwitayakorn; S. Tangphatsornruang

2011-01-01

18

Characterization of an 18,166 EST dataset for cassava ( Manihot esculenta Crantz) enriched for drought-responsive genes  

Microsoft Academic Search

Cassava (Manihot esculenta Crantz) is a staple food for over 600 million people in the tropics and subtropics and is increasingly used as an industrial\\u000a crop for starch production. Cassava has a high growth rate under optimal conditions but also performs well in drought-prone\\u000a areas and on marginal soils. To increase the tools for understanding and manipulating drought tolerance in

Y. Lokko; J. V. Anderson; S. Rudd; A. Raji; D. Horvath; M. A. Mikel; R. Kim; L. Liu; A. Hernandez; A. G. O. Dixon; I. L. Ingelbrecht

2007-01-01

19

Effect of Cassava (Manihot esculenta) Foliage Supplementation to Calves on the Viability and Egg Count of Haemonchus contortus Nematodes  

Microsoft Academic Search

Thirty early-weaned 5±3 month-old calves with an average body weight of 96±23 kg were used; 24 were artificially infested with 90 larvae (L3), of H. contortus per kilogram body weight. Calves grazed on African Star Grass (Cynodon plectostachyus) from 0600 to 1300 hours. Grazing was supplemented with lucerne hay (Medicago sativa) or cassava foliage (Manihot esculenta), and 500 g 1

Juan López; Esteban Machín; Arturo Zentella; Victor Vázquez; Irma Tejada; Armando Shimada

2007-01-01

20

Substrate specificity of mutants of the hydroxynitrile lyase from Manihot esculenta.  

PubMed

Several tryptophan128-substituted mutants of the hydroxynitrile lyase from Manihot esculenta (MeHNL) are constructed and applied in the MeHNL-catalyzed addition of HCN to various aromatic and aliphatic aldehydes as well as to methyl and ethyl ketones to yield the corresponding cyanohydrins. The mutants (especially MeHNL-W128A) are in most cases superior to the wild-type (wt) enzyme when diisopropyl ether is used as the solvent. Substitution of tryptophan128 by an alanine residue enlarges the entrance channel to the active site of MeHNL and thus facilitates access of sterically demanding substrates to the active site, as clearly demonstrated for aromatic aldehydes, especially 3-phenoxybenzaldehyde. These experimental results are in accordance with the X-ray crystal structure of MeHNL-W128A. Aliphatic aldehydes, surprisingly, do not demonstrate this reactivity dependence of mutants on substrate bulkiness. Comparative reactions of 3-phenoxybenzaldehyde with wtMeHNL and MeHNL-W128A in both aqueous citrate buffer and a two-phase system of water/methyl tert-butyl ether again reveal the superiority of the mutant enzyme: 3-phenoxybenzaldehyde was converted quantitatively into a cyanohydrin nearly independently of the amount of enzyme present, with a space-time yield of 57 g L(-1) h(-1). PMID:12616635

Bühler, Holger; Effenberger, Franz; Förster, Siegfried; Roos, Jürgen; Wajant, Harald

2003-03-01

21

Transgenic Biofortification of the Starchy Staple Cassava (Manihot esculenta) Generates a Novel Sink for Protein  

PubMed Central

Although calorie dense, the starchy, tuberous roots of cassava provide the lowest sources of dietary protein within the major staple food crops (Manihot esculenta Crantz). (Montagnac JA, Davis CR, Tanumihardjo SA. (2009) Compr Rev Food Sci Food Saf 8:181–194). Cassava was genetically modified to express zeolin, a nutritionally balanced storage protein under control of the patatin promoter. Transgenic plants accumulated zeolin within de novo protein bodies localized within the root storage tissues, resulting in total protein levels of 12.5% dry weight within this tissue, a fourfold increase compared to non-transgenic controls. No significant differences were seen for morphological or agronomic characteristics of transgenic and wild type plants in the greenhouse and field trials, but relative to controls, levels of cyanogenic compounds were reduced by up to 55% in both leaf and root tissues of transgenic plants. Data described here represent a proof of concept towards the potential transformation of cassava from a starchy staple, devoid of storage protein, to one capable of supplying inexpensive, plant-based proteins for food, feed and industrial applications.

Abhary, Mohammad; Siritunga, Dimuth; Stevens, Gene; Taylor, Nigel J.; Fauquet, Claude M.

2011-01-01

22

Size asymmetry in intraspecific competition and the density-dependence of inbreeding depression in a natural plant population: a case study in cassava (Manihot esculenta Crantz, Euphorbiaceae)  

Microsoft Academic Search

The effects of competition on the genetic composition of natural populations are not well understood. We combined demography and molecular genetics to study how intraspecific competition affects microevolution in cohorts of volunteer plants of cassava (Manihot esculenta) originating from seeds in slash- and-burn fields of Palikur Amerindians in French Guiana. In this clonally propagated crop, genotypic diversity is enhanced by

B. PUJOL; D. MCKEY

2006-01-01

23

Evolution of cassava ( Manihot esculenta Crantz) after recent introduction into a South Pacific Island system: the contribution of sex to the diversification of a clonally propagated crop  

Microsoft Academic Search

Cassava (Manihot esculenta Crantz) is a clonally propagated crop that was introduced into the South Pacific archipelago of Vanuatu in the 1850s. Based on a survey conducted in 10 different villages throughout the archipelago, we present here a study of its diversity. Farmers' knowledge about cultivation cycle and sexual reproduction of cassava was recorded during group interviews in each village.

J. Sardos; D. McKey; M. F. Duval; R. Malapa; J. L. Noyer; V. Lebot

2008-01-01

24

An EST-derived SNP and SSR genetic linkage map of cassava (Manihot esculenta Crantz).  

PubMed

Cassava (Manihot esculenta Crantz) is one of the most important food security crops in the tropics and increasingly being adopted for agro-industrial processing. Genetic improvement of cassava can be enhanced through marker-assisted breeding. For this, appropriate genomic tools are required to dissect the genetic architecture of economically important traits. Here, a genome-wide SNP-based genetic map of cassava anchored in SSRs is presented. An outbreeder full-sib (F1) family was genotyped on two independent SNP assay platforms: an array of 1,536 SNPs on Illumina's GoldenGate platform was used to genotype a first batch of 60 F1. Of the 1,358 successfully converted SNPs, 600 which were polymorphic in at least one of the parents and was subsequently converted to KBiosciences' KASPar assay platform for genotyping 70 additional F1. High-precision genotyping of 163 informative SSRs using capillary electrophoresis was also carried out. Linkage analysis resulted in a final linkage map of 1,837 centi-Morgans (cM) containing 568 markers (434 SNPs and 134 SSRs) distributed across 19 linkage groups. The average distance between adjacent markers was 3.4 cM. About 94.2% of the mapped SNPs and SSRs have also been localized on scaffolds of version 4.1 assembly of the cassava draft genome sequence. This more saturated genetic linkage map of cassava that combines SSR and SNP markers should find several applications in the improvement of cassava including aligning scaffolds of the cassava genome sequence, genetic analyses of important agro-morphological traits, studying the linkage disequilibrium landscape and comparative genomics. PMID:22419105

Rabbi, Ismail Yusuf; Kulembeka, Heneriko Philbert; Masumba, Esther; Marri, Pradeep Reddy; Ferguson, Morag

2012-03-15

25

Toxic effects of prolonged administration of leaves of cassava (Manihot esculenta Crantz) to goats.  

PubMed

Cassava (Manihot esculenta Crantz) is a major source of dietary energy for humans and domestic animals in many tropical countries. However, consumption of cassava is limited by its characteristic content of cyanogenic glycosides. The present work aimed to evaluate the toxic effects of ingestion of cassava leaves by goats for 30 consecutive days, and to compare the results with the toxic effects of cyanide in goats, which have been described previously. Eight Alpine cross-bred female goats were divided into two equal groups, and were treated with ground frozen cassava leaves at a target dose of 6.0mg hydrogen cyanide (HCN)/kg/day (treated animals), or with ground hay and water only (control group) by gavage for 30 consecutive days. Blood samples were collected on days 0, 7, 15, 21, and 30 for biochemical panel and cyanide determination. At the end of the experiment, fragments of pancreas, thyroid gland, liver, kidney, lungs, heart, spleen, and the whole central nervous system were collected for histopathological examination. Clinical signs were observed in all goats treated with cassava on the first day of the experiment. From the second day the dose of cassava leaves was reduced to 4.5mgHCN/kg/day. No changes were found in the blood chemical panel. A mild increase in the number of resorption vacuoles in the thyroid follicular colloid, slight vacuolation of periportal hepatocytes, and spongiosis of the mesencephalon were found in goats treated with cassava. The pattern of lesions seen in the present goats was similar to what has been described previously in cyanide-dosed goats. Thus, the toxic effects of the ingestion of cassava leaves by goats can be attributed to the action of cyanide released from cyanogenic glycosides, and none of the effects was promoted by these glycosides directly. PMID:19559583

Soto-Blanco, Benito; Górniak, Silvana Lima

2009-06-25

26

Proteome characterization of cassava (Manihot esculenta Crantz) somatic embryos, plantlets and tuberous roots  

PubMed Central

Background Proteomics is increasingly becoming an important tool for the study of many different aspects of plant functions, such as investigating the molecular processes underlying in plant physiology, development, differentiation and their interaction with the environments. To investigate the cassava (Manihot esculenta Crantz) proteome, we extracted proteins from somatic embryos, plantlets and tuberous roots of cultivar SC8 and separated them by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Results Analysis by liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS) yielded a total of 383 proteins including isoforms, classified into 14 functional groups. The majority of these were carbohydrate and energy metabolism associated proteins (27.2%), followed by those involved in protein biosynthesis (14.4%). Subsequent analysis has revealed that 54, 59, 74 and 102 identified proteins are unique to the somatic embryos, shoots, adventitious roots and tuberous roots, respectively. Some of these proteins may serve as signatures for the physiological and developmental stages of somatic embryos, shoots, adventitious roots and tuberous root. Western blotting results have shown high expression levels of Rubisco in shoots and its absence in the somatic embryos. In addition, high-level expression of ?-tubulin was found in tuberous roots, and a low-level one in somatic embryos. This extensive study effectively provides a huge data set of dynamic protein-related information to better understand the molecular basis underlying cassava growth, development, and physiological functions. Conclusion This work paves the way towards a comprehensive, system-wide analysis of the cassava. Integration with transcriptomics, metabolomics and other large scale "-omics" data with systems biology approaches can open new avenues towards engineering cassava to enhance yields, improve nutritional value and overcome the problem of post-harvest physiological deterioration.

2010-01-01

27

Isolation and characterization of a cDNA encoding granule-bound starch synthase in cassava (Manihot esculenta Crantz) and its antisense expression in potato  

Microsoft Academic Search

A tuber-specific cDNA library of cassava (Manihot esculenta Crantz) was constructed and a full-length cDNA for granule-bound starch synthase (GBSS, also known as waxy protein), the enzyme responsible for the synthesis of amylose in reserve starch, was cloned. Sequencing of the cloned cDNA showed that it has 74% identity with potato GBSS and 60–72% identity with GBSS from other plant

S. N. I. M. Salehuzzaman; E. Jacobsen; R. G. F. Visser

1993-01-01

28

Assessment of genetic variability in a traditional cassava (Manihot esculenta Crantz) farming system, using AFLP markers  

Microsoft Academic Search

Despite the urgent need to conserve domesticated plant genetic resources, and developing ‘on farm’ strategies of conservation, the impact of traditional farming practices and of their interaction with ecological factors on the structure and evolutionary dynamics of the genetic variability of crop populations has been little documented. We assessed the genetic variability of 31 varieties of cassava (M. esculenta Crantz)

M Elias; O Panaud; T Robert

2000-01-01

29

Comparative morphology, biology and histology of reproductive development in three lines of Manihot esculenta Crantz (Euphorbiaceae: Crotonoideae)  

PubMed Central

Background and aims Cassava (Manihot esculenta), a major food staple in the tropics and subtropics, thrives even in environments undergoing threatening climate change. To satisfy the increasing demand for crop improvement and overcome the limitations of conventional breeding, the introduction of inbreeding techniques such as the production of doubled haploid lines via androgenesis or gynogenesis offers advantages. However, comprehensive studies on cassava flower bud biology or structural development are lacking and precise structural and biological information is a prerequisite to enhance the efficiency of these techniques. Methodology The floral biology of three selected cassava lines was studied, focusing on morphology, phenology and pollen biology (quantity, viability and dimorphism). Histological studies were also conducted on microsporogenesis/microgametogenesis and megasporogenesis/megagameto-genesis to generate precise developmental data for these lines. Principal results Male and female cyathia have distinct developmental phases. Pollen viability was high during immature stages of plant development; however, pollen mortality was common at later stages. Pollen trimorphism in male gametophytes towards the larger or smaller pollen size, as compared with normal size, was observed. Ten characteristic events were identified in male gametogenesis and six in female gametogenesis that were correlated with flower bud diameter. Male gametophyte diameter at different developmental stages was also determined. Conclusions Results indicate that the three lines did not differ significantly, except regarding a few morphological aspects such as plant height, flower colour and number of male cyathia. Pollen grains were initially viable, but viability decreased drastically at later stages of growth. Abnormal meiosis or mitosis triggered pollen trimorphism. The demonstrated sequential events of reproductive development generated valuable information at the cellular level, which will help close the current information gap for cassava improvement via breeding programmes and doubled haploid plant production.

Perera, P. I. P.; Quintero, M.; Dedicova, B.; Kularatne, J. D. J. S.; Ceballos, H.

2013-01-01

30

Quantitative trait loci and candidate genes associated with starch pasting viscosity characteristics in cassava (Manihot esculenta Crantz).  

PubMed

Starch pasting viscosity is an important quality trait in cassava (Manihot esculenta Crantz) cultivars. The aim here was to identify loci and candidate genes associated with the starch pasting viscosity. Quantitative trait loci (QTL) mapping for seven pasting viscosity parameters was carried out using 100 lines of an F1 mapping population from a cross between two cassava cultivars Huay Bong 60 and Hanatee. Starch samples were obtained from roots of cassava grown in 2008 and 2009 at Rayong, and in 2009 at Lop Buri province, Thailand. The traits showed continuous distribution among the F1 progeny with transgressive variation. Fifteen QTL were identified from mean trait data, with Logarithm of Odds (LOD) values from 2.77-13.01 and phenotype variations explained (PVE) from10.0-48.4%. In addition, 48 QTL were identified in separate environments. The LOD values ranged from 2.55-8.68 and explained 6.6-43.7% of phenotype variation. The loci were located on 19 linkage groups. The most important QTL for pasting temperature (PT) (qPT.1LG1) from mean trait values showed largest effect with highest LOD value (13.01) and PVE (48.4%). The QTL co-localised with PT and pasting time (PTi) loci that were identified in separate environments. Candidate genes were identified within the QTL peak regions. However, the major genes of interest, encoding the family of glycosyl or glucosyl transferases and hydrolases, were located at the periphery of QTL peaks. The loci identified could be effectively applied in breeding programmes to improve cassava starch quality. Alleles of candidate genes should be further studied in order to better understand their effects on starch quality traits. PMID:23614826

Thanyasiriwat, T; Sraphet, S; Whankaew, S; Boonseng, O; Bao, J; Lightfoot, D A; Tangphatsornruang, S; Triwitayakorn, K

2013-04-24

31

Enzymatic enantioselective transcyanation of silicon-containing aliphatic ketone with (S)-hydroxynitrile lyase from Manihot esculenta.  

PubMed

(S)-Hydroxynitrile lyase from Manihot esculenta (MeHNL) was shown for the first time to be able to catalyze the enantioselective transcyanation of acetyltrimethylsilane (ATMS) with acetone cyanohydrin to form (S)-2-trimethylsilyl-2-hydroxyl-propionitrile in an aqueous/organic biphasic system. To better understand the reaction, various influential variables were examined. The most suitable organic phase, optimal buffer pH, aqueous phase content, shaking rate, temperature, concentration of ATMS, acetone cyanohydrin and crude enzyme were diisopropyl ether (DIPE), 5.4, 13% (v/v), 190 rpm, 40 degrees C, 10 mM, 20 mM, and 35 U/ml, respectively, under which the initial reaction rate, substrate conversion and product enantiomeric excess (e.e.) were 19.5 mM/h, 99.0% and 93.5%, respectively. A comparative study demonstrated that silicon atoms in the substrate had a great effect on the reaction, and that ATMS was a much better substrate for MeHNL than its carbon analogue 3,3-dimethyl-2-butanone (DMBO) with respect to the initial reaction rate, substrate conversion and product e.e. MeHNL has greater affinity towards ATMS than its carbon analogue as indicated by the much lower K(m). The activation energy of MeHNL-catalyzed transcyanation of ATMS was also markedly lower than that of DMBO. The silicon effect on the reaction was rationalized on the basis of the special characteristics of silicon atoms and the catalytic mechanism of MeHNL. PMID:15309340

Xu, Ruo; Zong, Min-Hua; Liu, Yu-Ying; He, Jun; Zhang, Yuan-Yuan; Lou, Wen-Yong

2004-08-12

32

Characterization of an 18,166 EST dataset for cassava (Manihot esculenta Crantz) enriched for drought-responsive genes.  

PubMed

Cassava (Manihot esculenta Crantz) is a staple food for over 600 million people in the tropics and subtropics and is increasingly used as an industrial crop for starch production. Cassava has a high growth rate under optimal conditions but also performs well in drought-prone areas and on marginal soils. To increase the tools for understanding and manipulating drought tolerance in cassava, we generated expressed sequence tags (ESTs) from normalized cDNA libraries prepared from dehydration-stressed and control well-watered tissues. Analysis of a total of 18,166 ESTs resulted in the identification of 8,577 unique gene clusters (5,383 singletons and 3,194 clusters). Functional categories could be assigned to 63% of the unigenes, while another approximately 11% were homologous to hypothetical genes with unclear functions. The remaining approximately 26% were not significantly homologous to sequences in public databases suggesting that some may be novel and putatively specific to cassava. The dehydration-stressed library uncovered numerous ESTs with recognized roles in drought-responses, including those that encode late-embryogenesis-abundant proteins thought to confer osmoprotective functions during water stress, transcription factors, heat-shock proteins as well as proteins involved in signal transduction and oxidative stress. The unigene clusters were screened for short tandem repeats for further development as microsatellite markers. A total of 592 clusters contained 646 repeats, representing 3.3% of the ESTs queried. The ESTs presented here are the first dehydration stress transcriptome of cassava and can be utilized for the development of microarrays and gene-derived molecular markers to further dissect the molecular basis of drought tolerance in cassava. PMID:17541599

Lokko, Y; Anderson, J V; Rudd, S; Raji, A; Horvath, D; Mikel, M A; Kim, R; Liu, L; Hernandez, A; Dixon, A G O; Ingelbrecht, I L

2007-05-31

33

Inhibition of chemically induced inflammation and pain by orally and topically administered leaf extract of Manihot esculenta Crantz in rodents.  

PubMed

The aqueous leaf extract of Manihot esculenta Crantz (MELE) is being used orally and topically in traditional African medicine for the treatment of inflammation and pain, and claimed to be safe. The anti-inflammatory effects of MELE (100-400 mg/kg, p.o. or 1-4%, w/w in petroleum jelly, topically) were tested against carrageenan-induced paw oedema in rats as well as against xylene-induced ear oedema in mice. The analgesic effect of MELE (100-400 mg/kg, p.o. or 1-4%, w/w in petroleum jelly, topically) was tested against acetic acid-induced (20 microl, 0.6%, v/v in normal saline, i.p.) and acetylcholine-induced (8.3 mg/kg, i.p.) mouse writhing models. At 100-400 mg/kg, p.o. and 1-4% (w/w), topically, MELE produced significant inhibitions of carrageenan-induced rat paw oedema and xylene-induced ear swelling in mice. Effects produced by MELE were significantly higher than those produced by indomethacin (10 mg/kg, s.c. or 1%, w/w in petroleum jelly) in the anti-inflammatory models. For the analgesic effect, MELE (100-400 mg/kg, orally) and (1-4%, w/w, topically), like aspirin (100 mg/kg, i.p.) exhibited significant (P<0.05) inhibition of acetic acid- and acetylcholine-induced mouse writhing tests, compared to untreated control. Effects produced by MELE were significantly lower than those produced by aspirin (100 mg/kg, i.p.) in the analgesic models, except for the topically administered extract on acetylcholine-induced pain. Acute oral administration up to 10 g/kg did not cause death within 14 days, but mortalities were produced in i.p. administered extract with LD(50) of 2.5+/-0.3 g/kg. Based on these, the extract may contain orally safe, topically and orally effective anti-inflammatory and analgesic principles, which justify its use in traditional African medicine. PMID:18675525

Adeyemi, Olufunmilayo O; Yemitan, Omoniyi K; Afolabi, Lateef

2008-05-28

34

Daniel W. Gade - Names for Manihot esculenta: Geographical Variations and Lexical Clarification - Journal of Latin American Geography 1:1  

Microsoft Academic Search

This study elucidates the derivations, distensions and distortions of the names for a major world crop domesticated in tropical America. In addition to the several Latin binomials, English speakers have used one or mare of six vernacular terms far this plant. Two of these words are straight borrowings (yuca from Spanish, mandioca from Portuguese and Spanish); one (yucca) implies and

Daniel W. Gade

2003-01-01

35

Provitamin A Accumulation in Cassava (Manihot esculenta) Roots Driven by a Single Nucleotide Polymorphism in a Phytoene Synthase Gene[W  

PubMed Central

Cassava (Manihot esculenta) is an important staple crop, especially in the arid tropics. Because roots of commercial cassava cultivars contain a limited amount of provitamin A carotenoids, both conventional breeding and genetic modification are being applied to increase their production and accumulation to fight vitamin A deficiency disorders. We show here that an allelic polymorphism in one of the two expressed phytoene synthase (PSY) genes is capable of enhancing the flux of carbon through carotenogenesis, thus leading to the accumulation of colored provitamin A carotenoids in storage roots. A single nucleotide polymorphism present only in yellow-rooted cultivars cosegregates with colored roots in a breeding pedigree. The resulting amino acid exchange in a highly conserved region of PSY provides increased catalytic activity in vitro and is able to increase carotenoid production in recombinant yeast and Escherichia coli cells. Consequently, cassava plants overexpressing a PSY transgene produce yellow-fleshed, high-carotenoid roots. This newly characterized PSY allele provides means to improve cassava provitamin A content in cassava roots through both breeding and genetic modification.

Welsch, Ralf; Arango, Jacobo; Bar, Cornelia; Salazar, Bertha; Al-Babili, Salim; Beltran, Jesus; Chavarriaga, Paul; Ceballos, Hernan; Tohme, Joe; Beyer, Peter

2010-01-01

36

Effects of high energy milling on some functional properties of jicama starch ( Pachyrrhizus erosus L. Urban) and cassava starch ( Manihot esculenta Crantz)  

Microsoft Academic Search

In this study, the effect of high energy milling using a Spex ball mixer mill on some functional properties of cassava starch (Manihot utilissima) and jicama starch (Pachyrrisus erosus) were investigated. The properties of individual granules were strongly influenced by the high moisture of ball milling (friction and heat) and physicochemical properties of their amorphous and crystalline zones. High energy

F. Martínez-Bustos; M. López-Soto; E. San Martín-Martínez; J. J. Zazueta-Morales; J. J. Velez-Medina

2007-01-01

37

The complete nucleotide sequence of the cassava (Manihot esculenta) chloroplast genome and the evolution of atpF in Malpighiales: RNA editing and multiple losses of a group II intron.  

PubMed

The complete sequence of the chloroplast genome of cassava (Manihot esculenta, Euphorbiaceae) has been determined. The genome is 161,453 bp in length and includes a pair of inverted repeats (IR) of 26,954 bp. The genome includes 128 genes; 96 are single copy and 16 are duplicated in the IR. There are four rRNA genes and 30 distinct tRNAs, seven of which are duplicated in the IR. The infA gene is absent; expansion of IRb has duplicated 62 amino acids at the 3' end of rps19 and a number of coding regions have large insertions or deletions, including insertions within the 23S rRNA gene. There are 17 intron-containing genes in cassava, 15 of which have a single intron while two (clpP, ycf3) have two introns. The usually conserved atpF group II intron is absent and this is the first report of its loss from land plant chloroplast genomes. The phylogenetic distribution of the atpF intron loss was determined by a PCR survey of 251 taxa representing 34 families of Malpighiales and 16 taxa from closely related rosids. The atpF intron is not only missing in cassava but also from closely related Euphorbiaceae and other Malpighiales, suggesting that there have been at least seven independent losses. In cassava and all other sequenced Malphigiales, atpF gene sequences showed a strong association between C-to-T substitutions at nucleotide position 92 and the loss of the intron, suggesting that recombination between an edited mRNA and the atpF gene may be a possible mechanism for the intron loss. PMID:18214421

Daniell, Henry; Wurdack, Kenneth J; Kanagaraj, Anderson; Lee, Seung-Bum; Saski, Christopher; Jansen, Robert K

2008-01-24

38

The complete nucleotide sequence of the cassava (Manihot esculenta) chloroplast genome and the evolution of atpF in Malpighiales: RNA editing and multiple losses of a group II intron  

PubMed Central

The complete sequence of the chloroplast genome of cassava (Manihot esculenta, Euphorbiaceae) has been determined. The genome is 161,453 bp in length and includes a pair of inverted repeats (IR) of 26,954 bp. The genome includes 128 genes; 96 are single copy and 16 are duplicated in the IR. There are four rRNA genes and 30 distinct tRNAs, seven of which are duplicated in the IR. The infA gene is absent; expansion of IRb has duplicated 62 amino acids at the 3? end of rps19 and a number of coding regions have large insertions or deletions, including insertions within the 23S rRNA gene. There are 17 intron-containing genes in cassava, 15 of which have a single intron while two (clpP, ycf3) have two introns. The usually conserved atpF group II intron is absent and this is the first report of its loss from land plant chloroplast genomes. The phylogenetic distribution of the atpF intron loss was determined by a PCR survey of 251 taxa representing 34 families of Malpighiales and 16 taxa from closely related rosids. The atpF intron is not only missing in cassava but also from closely related Euphorbiaceae and other Malpighiales, suggesting that there have been at least seven independent losses. In cassava and all other sequenced Malphigiales, atpF gene sequences showed a strong association between C-to-T substitutions at nucleotide position 92 and the loss of the intron, suggesting that recombination between an edited mRNA and the atpF gene may be a possible mechanism for the intron loss.

Wurdack, Kenneth J.; Kanagaraj, Anderson; Lee, Seung-Bum; Saski, Christopher; Jansen, Robert K.

2008-01-01

39

Diversity in oil content and fatty acid profile in seeds of Manihot species  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cassava (Manihot esculenta) is the only commercial species of the genus, cultivated mainly for its starchy tuber roots. Cassava seeds are known to be rich in oils and fats. However, there are very scant reports on the content and properties of oil from cassava seeds and its wild relatives, which usu...

40

Antioxidant phenolic compounds of cassava (Manihot esculenta) from Hainan.  

PubMed

An activity-directed fractionation and purification process was used to isolate antioxidant components from cassava stems produced in Hainan. The ethyl acetate and n-butanol fractions showed greater DPPH?and ABTS?+ scavenging activities than other fractions. The ethyl acetate fraction was subjected to column chromatography, to yield ten phenolic compounds: Coniferaldehyde (1), isovanillin (2), 6-deoxyjacareubin (3), scopoletin (4), syringaldehyde (5), pinoresinol (6), p-coumaric acid (7), ficusol (8), balanophonin (9) and ethamivan (10), which possess significant antioxidant activities. The relative order of DPPH? scavenging capacity for these compounds was ascorbic acid (reference) > 6 > 1 > 8 > 10 > 9 > 3 > 4 > 7 > 5 > 2, and that of ABTS?+ scavenging capacity was 5 > 7 > 1 > 10 > 4 > 6 > 8 > 2 > Trolox (reference compound) > 3 > 9. The results showed that these phenolic compounds contributed to the antioxidant activity of cassava. PMID:22157579

Yi, Bo; Hu, Lifei; Mei, Wenli; Zhou, Kaibing; Wang, Hui; Luo, Ying; Wei, Xiaoyi; Dai, Haofu

2011-12-07

41

A molecular genetic map of cassava (Manihot esculenta Crantz)  

Microsoft Academic Search

A genetic linkage map of cassava has been constructed with 132 RFLPs, 30 RAPDs, 3 microsatellites, and 3 isoenzyme markers\\u000a segregating from the heterozygous female parent of an intraspecific cross. The F1 cross was made between ‘TMS 30572’ and ‘CM?2177-2’, elite cassava cultivars from Nigeria and Colombia, respectively. The\\u000a map consists of 20 linkage groups spanning 931.6?cM or an estimated

M. Fregene; F. Angel; R. Gomez; F. Rodriguez; P. Chavarriaga; W. Roca; J. Tohme; M. Bonierbale

1997-01-01

42

The primary gene pool of cassava (Manihot esculenta Crantz subspecies esculenta, Euphorbiaceae)  

Microsoft Academic Search

The primary gene pool (GP-1) of a crop is composed of gene reservoirs that cross easily with the domesticated, while the crosses\\u000a regularly produce fertile offspring. The GP-1 is further subdivided into cultivated and wild gene pools. The cultivated gene\\u000a pool encompasses commercial stocks of the crop, as well as landraces. The wild GP-1 of the crop comprises putative ancestors

A. C. Allem; R. A. Mendes; A. N. Salomão; M. L. Burle

2001-01-01

43

Conservación y Acondicionamiento de las Raíces Frescas  

Microsoft Academic Search

La yuca (Manihot esculenta) es un alimento importante porque es fuente económica de calorías, especialmente para las gentes de pocos recursos económicos que habitan las regiones tropicales del mundo. Por tal razón, los científicos han hecho grandes esfuerzos para desarrollar variedades de mayor rendimiento y para diseñar tecnologías apropiadas de bajos insumos que mejoren la producción del cultivo. La aplicación

Teresa Sánchez; Lisímaco Alonso

44

Starch granule size and the domestication of manioc ( Manihot esculenta ) and sweet potato (Ipomoea batatas)  

Microsoft Academic Search

Archaeological studies of plant remains have indicated that an increase in seed size is frequently correlated with both intensive\\u000a cultivation and domestication of seed crop plants. To test if starch granules of domesticated root crops are significantly\\u000a larger than those of wild or less intensively cultivated plants, archaeological and modern specimens of manioc and sweet potato\\u000a were sampled for starch

Linda Perry; Economu Botany

2002-01-01

45

Retention of total carotenoid and ?-carotene in yellow sweet cassava (Manihot esculenta Crantz) after domestic cooking  

PubMed Central

Background Over the last decade, considerable efforts have been made to identify cassava cultivars to improve the vitamin A nutritional status of undernourished populations, especially in northeast Brazil, where cassava is one of the principal and essentially only nutritional source. Objectives The aim of this study was to evaluate the total carotenoid, ?-carotene, and its all-E-, 9-, and 13-Z-?-carotene isomers content in seven yellow sweet cassava roots and their retention after three boiling cooking methods. Design The total carotenoid, ?-carotene, and its all-E-, 9-, and 13-Z-?-carotene isomers in yellow sweet cassava samples were determined by ultraviolet/visible spectrometry and high-performance liquid chromatography, respectively, before and after applying the cooking methods. All analyses were performed in triplicate. Results The total carotenoid in raw roots varied from 2.64 to 14.15 µg/g and total ?-carotene from 1.99 to 10.32 µg/g. The ?-carotene predominated in all the roots. The Híbrido 2003 14 08 cultivar presented the highest ?-carotene content after cooking methods 1 and 3. The 1153 – Klainasik cultivar presented the highest 9-Z-?-carotene content after cooking by method 3. The highest total carotenoid retention was observed in cultivar 1456 – Vermelhinha and that of ?-carotene for the Híbrido 2003 14 11 cultivar, both after cooking method 1. Evaluating the real retention percentage (RR%) in sweet yellow cassava after home cooking methods showed differences that can be attributed to the total initial carotenoid contents. However, no cooking method uniformly provided a higher total carotenoid or ?-carotene retention in all the cultivars. Conclusion Differences were found in the cooking methods among the samples regarding total carotenoid or ?-carotene retention, suggesting that the different behaviors of the cultivars need to be further analyzed. However, high percentages of total carotenoid or ?-carotene retention were observed and can minimize vitamin A deficiency in low-income populations.

Carvalho, Lucia M. J.; Oliveira, Alcides R. G.; Godoy, Ronoel L. O.; Pacheco, Sidney; Nutti, Marilia R.; de Carvalho, Jose L. V.; Pereira, Elenilda J.; Fukuda, Wania G.

2012-01-01

46

Characterization and genetic distance analysis of cassava ( Manihot esculenta Crantz) germplasm from Mozambique using RAPD fingerprinting  

Microsoft Academic Search

Twenty-eight cassava genotypes from Mozambique, along with seven genotypes from Angola, Madagascar, Nigeria, Togo, Columbia,\\u000a and Thailand for comparison, were fingerprinted using random amplified polymorphic DNA (RAPD) analysis. The Mozambican material\\u000a represented a wide range of landraces. A total of 311 scored RAPD loci were used to calculate genetic distances between the\\u000a genotypes. This revealed an average genetic distance of

A. M. Zacarias; A.-M. Botha; M. T. Labuschagne; I. R. M. Benesi

2004-01-01

47

An ordered EST catalogue and gene expression profiles of cassava ( Manihot esculenta ) at key growth stages  

Microsoft Academic Search

A cDNA library was constructed from the root tissues of cassava variety Huanan 124 at the root bulking stage. A total of 9,600\\u000a cDNA clones from the library were sequenced with single-pass from the 5?-terminus to establish a catalogue of expressed sequence\\u000a tags (ESTs). Assembly of the resulting EST sequences resulted in 2,878 putative unigenes. Blastn analysis showed that 62.6%

You-Zhi Li; Ying-Hua Pan; Chang-Bin Sun; Hai-Tao Dong; Xing-Lu Luo; Zhi-Qiang Wang; Ji-Liang Tang; Baoshan Chen

2010-01-01

48

Cloning and characterization of a tuberous root-specific promoter from cassava (Manihot esculenta Crantz).  

PubMed

In order to obtain a tuberous root-specific promoter to be used in the transformation of cassava, a 1,728 bp sequence containing the cassava granule-bound starch synthase (GBSSI) promoter was isolated. The sequence proved to contain light- and sugar-responsive cis elements. Part of this sequence (1,167 bp) was cloned into binary vectors to drive expression of the firefly luciferase gene. Cassava cultivar Adira 4 was transformed with this construct or a control construct in which the luciferase gene was cloned behind the 35S promoter. Luciferase activity was measured in leaves, stems, roots and tuberous roots. As expected, the 35S promoter induced luciferase activity in all organs at similar levels, whereas the GBSSI promoter showed very low expression in leaves, stems and roots, but very high expression in tuberous roots. These results show that the cassava GBSSI promoter is an excellent candidate to achieve tuberous root-specific expression in cassava. PMID:23132522

Koehorst-van Putten, Herma J J; Wolters, Anne-Marie A; Pereira-Bertram, Isolde M; van den Berg, Hans H J; van der Krol, Alexander R; Visser, Richard G F

2012-11-07

49

A simple and low-cost strategy for micropropagation of cassava (Manihot esculenta Crantz)  

Microsoft Academic Search

With the aim of transferring micropropagation techniques to cassava seed producers, a simple and low- cost medium for in vitro micropropagation was developed. CM6740-7 cassava cultivar from CIAT was used as planting material. Commercially available nutrients were used in order to substitute the propagation media components. A Hydro Agris fertilizer (12-11-18\\/3 (MgO-EDTA)) was used as a substitute for Murashige and

M. A. Santana; G. Romay; J. Matehus; J. L. Vicente-Villardón; J. R. Demey

2009-01-01

50

Molecular and supra-molecular structure of waxy starches developed from cassava (Manihot esculenta Crantz).  

PubMed

The aim of this work was to characterize the amylopectin of low amylose content cassava starches obtained from transgenesis comparatively with a natural waxy cassava starch (WXN) discovered recently in CIAT (International Center for Tropical Agriculture). Macromolecular features, starch granule morphology, crystallinity and thermal properties of these starches were determined. M¯(w) of amylopectin from the transgenic varieties are lower than WXN. Branched and debranched chain distributions analyses revealed slight differences in the branching degree and structure of these amylopectins, principally on DP 6-9 and DP>37. For the first time, a deep structural characterization of a series of transgenic lines of waxy cassava was carried out and the link between structural features and the mutated gene expression approached. The transgenesis allows to silenced partially or totally the GBSSI, without changing deeply the starch granule ultrastructure and allows to produce clones with similar amylopectin as parental cassava clone. PMID:23399176

Rolland-Sabaté, Agnès; Sanchez, Teresa; Buléon, Alain; Colonna, Paul; Ceballos, Hernan; Zhao, Shan-Shan; Zhang, Peng; Dufour, Dominique

2012-10-27

51

Exploring the African cassava (Manihot esculenta Crantz) germplasm for somatic embryogenic competence  

Microsoft Academic Search

Somatic-embryogenic competence of eleven cassava genotypes was determined in induction media containing 8 and 12 mg\\/l of the auxin picloram, using axillary meristems and leaf lobes as explants. There were significant differences (p<0.01) among the cassava genotypes for ability to form somatic embryos. Proembryo formation took between 27 to 35 days and ranged between 34.5% for TME 596 and 0%

J. Atehnkeng; V. O. Adetimirin; S. Y. C. Ng

52

Bio-ethanol production from non-food parts of cassava (Manihot esculenta Crantz).  

PubMed

Global climate issues and a looming energy crisis put agriculture under pressure in Sub-Saharan Africa. Climate adaptation measures must entail sustainable development benefits, and growing crops for food as well as energy may be a solution, removing people from hunger and poverty without compromising the environment. The present study investigated the feasibility of using non-food parts of cassava for energy production and the promising results revealed that at least 28% of peels and stems comprise dry matter, and 10 g feedstock yields >8.5 g sugar, which in turn produced >60% ethanol, with pH ? 2.85, 74-84% light transmittance and a conductivity of 368 mV, indicating a potential use of cassava feedstock for ethanol production. Thus, harnessing cassava for food as well as ethanol production is deemed feasible. Such a system would, however, require supportive policies to acquire a balance between food security and fuel. PMID:22535425

Nuwamanya, Ephraim; Chiwona-Karltun, Linley; Kawuki, Robert S; Baguma, Yona

2011-10-11

53

Isolation and characterization of amylase from fermented cassava (Manihot esculenta Crantz) waste- water  

Microsoft Academic Search

The processing of cassava tubers for the production of nutrient enriched cassava flour, gari and farinha madioca, is usually accompanied with the production of stinking wastewater which usually constitute nuisance to both terrestrial and aquatic life. Thus, this study sought to assess the potential utilization of the wastewater as a source of industrial amylase. Wastewater from cassava mash fermented with

Ganiyu Oboh

54

Response of cassava (Manihot esculenta Crantz) to water stress and fertilization  

Microsoft Academic Search

Experiments done in Santander de Quilichao (Cauca, Colombia) on two cassava cultivars indicated that cassava had at least\\u000a three defence mechanisms against water deficit, enabling it to assimilate and store photosynthates in roots, even during prolonged\\u000a droughts. These mechanisms include partial stomatal closure, ability of leaves to maintain reasonable net photosynthetic rate\\u000a for long periods of water stress, reduced leaf

S. M. De Tafur; M. A. El-Sharkawy; L. F. Cadavid

1997-01-01

55

Sensory characteristics of fufu prepared with cassava roots (Manihot esculenta Crantz) stored in polyethylene sacks  

Microsoft Academic Search

AbstractThis study was carried out to assess the effect of storage of cassava roots in polyethylene sacks for periods of 2, 4, 6 and 8?weeks on the sensory characteristics of cassava fufu, a popular Ghanaian dish. Freshly harvested cassava roots were dipped in tap water and packed into polyethylene sacks in 2-kg batches and stored at room temperature (25°C?±?1°C). Samples

Clara Opare-Obisaw; Isaac Kojo Asante; Ekua Koba Annan

2004-01-01

56

Sequestering of Cu(II) from aqueous solution using cassava peel (Manihot esculenta).  

PubMed

Cassava peel is a prospective cheap biosorbent for metal ions sequestration. In this research, the ability of cassava peel to remove Cu(II) from aqueous solution was evaluated. Its physical characteristics were probed by nitrogen adsorption measurements and scanning electron microscopy while its biosorption mechanism was studied by Fourier Transform Infrared (FTIR), Scanning Electron Microscopy/Energy Dispersive using X-ray analysis-(SEM/EDX), X-ray mapping and X-ray Photoelectron Spectroscopy (XPS). Biosorption experiments were carried out isothermally at three different temperatures (30 degrees C, 45 degrees C and 60 degrees C) in a static mode. The maximum adsorption capacity (41.77 mg g(-1)) was attained at the highest temperature. The pH and particle size effects in relation to biosorption capacity were also discussed. In addition, Langmuir, Freundlich, Sips and Toth equations were tested for data correlation. Langmuir and Freundlich models were the best choices since they contained less parameter with equally good fitting performance in comparison to the other three parameters equations. For kinetic studies, sorption rates were better represented using a pseudo second-order expression in comparison to a more commonly used pseudo first-order equation. Also, thermodynamic variables showed that the process was spontaneous (DeltaG<0), endothermic (DeltaH>0) and irreversible (DeltaS>0). PMID:20471169

Kosasih, Aline Natasia; Febrianto, Jonathan; Sunarso, Jaka; Ju, Yi-Hsu; Indraswati, Nani; Ismadji, Suryadi

2010-04-24

57

CARACTERIZAÇÃO DA SILAGEM DO TERÇO SUPERIOR DA RAMA DE MANDIOCA Manihot esculenta CRANTZ  

Microsoft Academic Search

The objective of experiment was determine the chemical composition of the superior third of the cassava foliage silage. The experiment was conducted at Iguatemi Experimental Farm of the State University of Maringá in Brazil. Cassava was ensiled in laboratory silos. The ensiled material was removed randomly according to used of silos. Silage samples were collected at eight different periods and

ELISA CRISTINA MODESTO; DUARTE VILELA; JOSIANE FAUSTINO; JÚLIO CESAR DAMASCENO; EDENIO DETMANN

58

Computational identification of microRNAs and their targets in cassava (Manihot esculenta Crantz.).  

PubMed

MicroRNAs (miRNAs) are a newly discovered class of noncoding endogenous small RNAs involved in plant growth and development as well as response to environmental stresses. miRNAs have been extensively studied in various plant species, however, only few information are available in cassava, which serves as one of the staple food crops, a biofuel crop, animal feed and industrial raw materials. In this study, the 169 potential cassava miRNAs belonging to 34 miRNA families were identified by computational approach. Interestingly, mes-miR319b was represented as the first putative mirtron demonstrated in cassava. A total of 15 miRNA clusters involving 7 miRNA families, and 12 pairs of sense and antisense strand cassava miRNAs belonging to six different miRNA families were discovered. Prediction of potential miRNA target genes revealed their functions involved in various important plant biological processes. The cis-regulatory elements relevant to drought stress and plant hormone response were identified in the promoter regions of those miRNA genes. The results provided a foundation for further investigation of the functional role of known transcription factors in the regulation of cassava miRNAs. The better understandings of the complexity of miRNA-mediated genes network in cassava would unravel cassava complex biology in storage root development and in coping with environmental stresses, thus providing more insights for future exploitation in cassava improvement. PMID:22388699

Patanun, Onsaya; Lertpanyasampatha, Manassawe; Sojikul, Punchapat; Viboonjun, Unchera; Narangajavana, Jarunya

2013-03-01

59

Molecular Evolution and Functional Divergence of Soluble Starch Synthase Genes in Cassava (Manihot Esculenta Crantz)  

PubMed Central

Soluble starch synthases (SSs) are major enzymes involved in starch biosynthesis in plants. Cassava starch has many remarkable characteristics, which should be influenced by the evolution of SS genes in this starchy root crop. In this work, we performed a comprehensive phylogenetic and evolutionary analysis of the soluble starch synthases in cassava. Genome-wide identification showed that there are 9 genes encoding soluble starch synthases in cassava. All of the soluble starch synthases encoded by these genes contain both Glyco_transf_5 and Glycos_transf_1 domains, and a correlation analysis showed evidence of coevolution between these 2 domains in cassava SS genes. The SS genes in land plants can be divided into 6 subfamilies that were formed before the origin of seed plants, and species-specific expansion has contributed to the evolution of this family in cassava. A functional divergence analysis for this family provided statistical evidence for shifted evolutionary rates between the subfamilies of land plant soluble starch synthases. Although the main selective pressure acting on land plant SS genes was purifying selection, our results also revealed that point mutation with positive selection contributed to the evolution of 2 SS genes in cassava. The remarkable cassava starch characteristics might be the result of both the duplication and adaptive selection of SS genes.

Yang, Zefeng; Wang, Yifan; Xu, Shuhui; Xu, Chenwu; Yan, Changjie

2013-01-01

60

Resistance to the Whitefly, Aleurotrachelus socialis, in Wild Populations of Cassava, Manihot Tristis  

PubMed Central

The levels of resistance in the wild species of cassava, Manihot tristis Muell-Arg. (Malpighiales: Euphorbiaceae), to the whitefly, Aleurotrachelus socialis Bondar (Hemiptera: Alelyrodidae), the most important economic pest in cassava, Manihot esculenta Crantz (Malpighiales: Euphorbiaceae) crops in South America, were estimated under glasshouse conditions. The parameters of the life history of A. socialis were studied on TST-26 and TST-18 accessions of the wild parent and compared with the susceptible (CMC-40) and resistant (MEcu-72) cultivars. The average longevity on the wild accessions (TST-26, 4.1; TST-18, 4.6 days) and oviposition rates (TST-26, 2.0; TST-18, 1.6 eggs/female/2 days) of the A. socialis females were not significantly different from those of MEcu-72 (5.1 days and 3.4 eggs/female/2days). The longevity and oviposition rates on CMC-40 were highest (11 days and 8.6 eggs/female/2days). Analyses of the demographic parameters (Ro, rm; DT) showed a significant impact of the M. tristis accessions on the potential growth of A. socialis. The average survival time of adults that fed on TST-26, TST-18, and MEcu-72 were significantly different from those recorded on the susceptible genotype. Results from this study revealed important levels of resistance to the whitefly A. socialis on the TST-26 and TST-18 accessions due to the marked differences found for longevity and reproduction, which influenced and were consistent with the differences found in the net reproduction rate (Ro), intrinsic growth rate (rm) and population doubling time (DT). The combined effect of these parameters indicated that M. tristis accessions were inappropriate hosts for A. socialis.

Carabali, A.; Bellotti, A. C.; Montoya-Lerma, J.; Fregene, Martin

2010-01-01

61

Growth performance of Alaria esculenta off helgoland  

Microsoft Academic Search

Alaria esculenta (L.) Grev. sporophytes, raised in culture and originating from the North of Iceland were immersed in the sea near Helgoland (North Sea) for the period from February to August. Notable growth of the thalli was found between February and May, when the water temperature was similar to that of their original habitat in Iceland. Less conspicuous growth but

I. M. Munda; K. Lüning

1977-01-01

62

Production of Microconidia by Cercospora henningsii Allesch, Cause of Brown Leaf Spot of Cassava ( Manihot esculenta Crantz) and Tree Cassava ( Manihot glaziovii Muell.Arg.)  

Microsoft Academic Search

Sporulation ofCercospora henningsiiAllesch has been examined under various relative humidities, and in the presence of free water in lesions on leaves of cassava and tree cassava. Mature conidia of the fungus on both cassava and tree cassava do not germinate in lesions but accumulate, and under the optimum conditions of 25–32 °C and in the presence of free water, they

E. N. AYESU-OFFEI; C. ANTWI-BOASIAKO

1996-01-01

63

Method for producing Abelmoschus manihot medicus flower perfumed product  

US Patent & Trademark Office Database

A producing method of Abelmoschus manihot Medicus flower perfumed products comprises steps of choosing a carrier from one of Abelmoschus manihot Medicus oil, vegetable oil with unsaturated fatty acid more than 60% and acid value less than 4.0, and cosmetic base oil grade high purity mineral oil; choosing Abelmoschus manihot Medicus flowers as main ingredient flowers; immersing the main ingredient flowers in the carrier by immersing the main ingredient flowers below a liquid level of the carrier; and placing stationarily the carrier with the main ingredient flowers immersed therein in dark places and keeping the carrier out of any direct sunlight under an environment with a temperature between 18 degrees centigrade and 48 degrees centigrade for more than 6 hours, or a temperature below 18 degrees centigrade for more than 180 hours.

2013-01-01

64

Bacterial artificial chromosome (BAC) library resource for positional cloning of pest and disease resistance genes in cassava ( Manihot esculenta Crantz)  

Microsoft Academic Search

Pest and disease problems are important constraints of cassava production and host plant resistance is the most efficient method of combating them. Breeding for host plant resistance is considerably slowed down by the crop’s biological constraints of a long growth cycle, high levels of heterozygosity and a large genetic load. More efficient methods such as gene cloning and transgenesis are

J. Tomkins; M. Fregene; D. Main; H. Kim; R. Wing; J. Tohme

2004-01-01

65

The area of origin of Manihot esculenta as a crop plant—a review of the evidence  

Microsoft Academic Search

Conclusion  It has been suggested by Mangelsdorf and his co-workers (1964) that the two subdivisions (according to toxicity) into which\\u000a cultivated manioc falls “had a separate and local history of cultivation,” and an examination of the evidence presented above\\u000a makes it possible to elaborate on this suggestion.\\u000a \\u000a It may be proposed that sweet manioc was first domesticated in Mesoamerica as one

Barbara S. Renvoize

1972-01-01

66

Identification of actively filling sucrose sinks. [Solanum tuberosum; Phaseolus lunatus; Manihot esculenta; Liquidambar styraciflua L. ; Carya illinoinensis  

SciTech Connect

Certain actively filling plant sucrose sinks such as a seed, a tuber, or a root can be identified by measuring the uridine diphosphate and pyrophosphate-dependent metabolism of sucrose. Sucrolysis in both active and quiescent sucrose sinks was tested and sucrose synthase was found to be the predominant sucrose breakdown activity. Sucrolysis via invertases was low and secondary in both types of sinks. Sucrose synthase activity dropped markedly, greater than fivefold, in quiescent sinks. The test are consistent with the hypothesis that the sucrose filling activity, i.e. the sink strength, of these plant sinks can be measured by testing the uridine diphosphate and pyrophosphate-dependent breakdown of sucrose. Measuring the initial reactions of sucrolysis shows much promise for use in agriculture crop and tree improvement research as a biochemical test for sink strength.

Sung, Shijean S.; Xu, Dianpeng; Black C.C. (Univ. of Georgia, Athens (USA))

1989-04-01

67

An efficient mass propagation system for cassava (Manihot esculenta Crantz) based on nodal explants and axillary bud-derived meristems  

Microsoft Academic Search

Nodes from 3- to 5-week-old in vitro plants of different cassava cultivars were cultured for 2-3 days on solid Murashige and Skoog basal medium supplemented with cytokinin to induce the enlargement of axillary buds. Subculture of these buds on the same medium resulted in multiple shoot formation within 4-6 weeks. Of the four cytokinins tested (6-benzylaminopurine (BAP), thidiazuron (TDZ), zeatin,

N. K. Konan; C. Schöpke; R. Cárcamo; R. N. Beachy C. Fauquet

1997-01-01

68

Variations in the chemical composition of cassava ( Manihot esculenta Crantz) leaves and roots as affected by genotypic and environmental variation.  

PubMed

The purpose of this study was to assess the quality of cassava cultivars, in terms of cyanogenic potential and composition of macro- and micronutrients, sampled from different locations in rural Mozambique. Total cyanide concentrations in fresh cassava tissues were measured using portable cyanide testing kits, and elemental nutrients were later analyzed from dried plant tissue. Variation in cyanogenic potential and nutrient composition occurred both among cultivars and across locations. The majority of cultivars contained >100 ppm total cyanide, fresh weight, and are therefore considered to be dangerously poisonous unless adequately processed before consumption. Leaf cyanogenic and nutrient content varied with plant water status, estimated using carbon isotope discrimination (?(13)C). The colonization of roots of all cultivars by arbuscular mycorrhizal fungi was also quantified and found to be high, indicating that mycorrhizas could play a key role in plant nutrient acquisition in these low-input farming systems. PMID:22515684

Burns, Anna Elizabeth; Gleadow, Roslyn Margaret; Zacarias, Anabela M; Cuambe, Constantino Estevão; Miller, Rebecca Elizabeth; Cavagnaro, Timothy Richard

2012-05-04

69

Mercury in the surface soil and cassava, Manihot esculenta (flesh, leaves and peel) near goldmines at Bogoso and Prestea, Ghana.  

PubMed

Mercury amalgamation is used indiscriminately in the recovery of gold by small-scale native gem winners in Ghana. Mercury is released into the environment in the form of wastewater, tailing and vapor from the roasting of amalgam to separate gold. The study looked at the levels of total mercury concentration in surface soil and cassava crop from farms located within the vicinities of Bogoso and Prestea Goldmines. The surface soil total mercury concentrations ranged between 125.29 and 352.52 ?g/kg whiles cassava had between 66.60 and 195.47 ?g/kg. The results showed proportionately more deposits at higher distances in 15-30 cm soil zone and less deposits at higher distances on leaves with relatively high uptake of the metal occurred at higher distances from the mines into the peels. These results suggest serious mercury pollution to the surface soil and the cassava crop but the speciation exercise showed that mercury is not in the free state, rather bound to hydroxides and organic compounds as complexes. PMID:23052587

Adjorlolo-Gasokpoh, A; Golow, A A; Kambo-Dorsa, J

2012-10-07

70

Chlorophyll Fluorescence Analysis for Assessing Water Deficit and Arbuscular Mycorrhizal Fungi (AMF) Inoculation in Cassava (Manihot esculenta Crantz)  

Microsoft Academic Search

Arbucsular Mycorrhizal Fungi (AMF) are implicated as phyto-stimulators of various physiological processes of its symbiotic plants. The influences of AM fungi and water deficit on quantum yield of photochemistry (Fv\\/Fm) of photo-system II of cassava leaves were therefore investigated. Field experiment was conducted at Ajibode village while the semi-controlled experiment was conducted at the International Institute of Tropical Agriculture (IITA),

O. J. Oyetunji; I. J. Ekanayake; O. Osonubi

71

Utilization of unpeeled cassava (Manihot esculenta Crantz) root meal supplemented with or without charcoal by broiler chickens.  

PubMed

A 42-day feeding trial was conducted using 480-day-old, male Marshall broilers to study the utilization of unpeeled cassava root meal (UCRM) supplemented with or without 6 g/kg charcoal. The experimental design was laid out in a 3 × 2 factorial arrangement of treatments having three inclusion levels of UCRM (0, 100 and 200 g/kg) with or without 6 g/kg charcoal supplementation. Each treatment consisted of 80 birds replicated eight times with 10 birds per replicate. Main effect of inclusion level of UCRM and supplementation of charcoal showed reduced (p < 0.05) final live weight, weight gain, feed intake and apparent crude protein digestibility of the birds with increasing inclusion levels of UCRM. Birds fed diets supplemented with charcoal showed higher (p < 0.05) final live weight, weight gain and feed intake than birds fed diets without charcoal. Supplementation of charcoal in diet containing 100 g/kg UCRM resulted in improved (p < 0.05) weight gain when compared with birds fed similar diet but not supplemented with charcoal. Broilers fed diet containing no UCRM but supplemented with charcoal had the highest overall (p < 0.05) final live weight and weight gain, while birds fed diet containing 200 g/kg UCRM supplemented with charcoal recorded the poorest (p < 0.05) final live weight and weight gain. Serum glutamate oxaloacetate transaminase (SGOT) and serum thiocyanate concentration increased (p < 0.05) with increasing dietary inclusion levels of UCRM. Dietary supplementation of charcoal resulted in increased (p < 0.05) concentration of serum glucose and cholesterol and reduced (p < 0.05) SGOT concentration. Birds fed diets containing UCRM had high (p < 0.05) serum thiocyanate concentration irrespective of dietary supplementation or not with 6 g/kg charcoal. In conclusion, supplementation of diet containing up to 100 g/kg UCRM with 6 g/kg charcoal showed improved weight gain without any deleterious effect on serum metabolites. PMID:23721067

Oso, A O; Akapo, O; Sanwo, K A; Bamgbose, A M

2013-05-31

72

Effects of Plant Growth Regulators and Saccharide on In Vitro Plant and Tuberous Root Regeneration of Cassava ( Manihot esculenta Crantz)  

Microsoft Academic Search

A faster system to get tuberous roots from in vitro cultured cassava plants may enhance the process of exploring the function\\u000a and practical application of some root-specific expressed genes. The effects of cytokinin, auxin, sucrose, maltose, and glucose\\u000a on development of shoots and tuberous roots and plantlet regeneration of in vitro cultured cassava were investigated in this\\u000a study. The cytokinin

Mingxia Fan; Zaochang Liu; Liguo Zhou; Tian Lin; Yunhua Liu; Lijun Luo

2011-01-01

73

Effect of resistant starch on the cooking quality of yam (Dioscorea spp.) and cassava (Manihot esculenta) based paste products.  

PubMed

Total starch (TS) and resistant starch (RS) contents in pasty edible product of mealy and hard cooking tubers of three yam varieties and four cassava varieties were determined to evaluate their contribution in their cooking quality. TS and RS contents appeared as the main components in determining yam cooking quality. Mealy cooking yam varieties were characterized by a significant higher TS content (75.2 ± 7.7 g/100 g d.m.) and lower RS content (13.8 ± 3.4 g/100 g d.m.) than hard cooking yam varieties, which, in contrast, contained less TS (61.7 ± 12.1 g/100 g d.m.) and particularly high RS (21.8 ± 9.9 g/100 g d.m.), possibly as a consequence of the prevalence of large granules (35-40 ?m) observed by light microscope. Conversely, TS and RS contents appeared not determinant on the cooking quality of cassava. Moreover, higher amylose contents were associated with substantially elevated percentages of RS in yam and cassava, and high RS content in samples modulates their pasting properties by reducing the peak viscosity and the breakdown and requiring higher temperature and longer time to the peak. PMID:23215529

Kouadio, Olivier Kouadio; N'dri, Denis Yao; Nindjin, Charlemagne; Marti, Alessandra; Casiraghi, Maria Cristina; Faoro, Franco; Erba, Daniela; Bonfoh, Bassirou; Amani, N'guessan Georges

2012-12-07

74

Production of transgenic cassava ( Manihot esculenta Crantz) plants by particle bombardment using luciferase activity as selection marker  

Microsoft Academic Search

Cassava embroids derived from friable embryogenic callus of the genotype TMS60444 were bombarded with DNA of the constructs pJIT100 or pJIT64. Both constructs contain the non-invasive reporter gene luciferase from firefly driven by the CaMV 35S promoter. The influence of several particle gun machine parameters and pretreatment of plant material on transient luciferase activity were studied to determine the most

C. J. J. M. Raemakers; E. Sofiari; N. Taylor; G. Henshaw; E. Jacobsen; R. G. F. Visser

1996-01-01

75

AFLP analysis of relationships among cassava and other Manihot species  

Microsoft Academic Search

Despite the worldwide importance of cultivated cassava (M. esculenta Crantz) its origin and taxonomic relationships with other species in the genus have not been clearly established. We evaluated\\u000a a representative sample of the crop’s diversity and six wild taxa with AFLPs to estimate genetic relationships within the\\u000a genus. Groupings of accessions of each species by data analysis corresponded largely with

A. C. Roa; M. M. Maya; M. C. Duque; J. Tohme; A. C. Allem; M. W. Bonierbale

1997-01-01

76

[Absorption of flavonoids from Abelmoschus manihot extract by in situ intestinal perfusion].  

PubMed

To explore the mechanism of the absorption of flavonoids from Abelmoschus manihot flowers, in situ intestinal recirculation was performed to study the effect of the absorption at different concentrations and different intestinal regions. To evaluate the conditions of the absorption of six flavonoids from Abelmoschus manihot flowers, the concentrations of Abelmoschus manihot in the perfusion solution were determined by HPLC at predesigned time. And we have investigated the inhibitory effect of six flavonoids from Abelmoschus manihot flowers on P-glycoprotein (P-gp) drug efflux pump. The results demonstrated that the absorption rates of flavonoids from Abelmoschus manihot flowers are not significantly different (P > 0.05) at various drug concentrations, the absorption of flavonoids from Abelmoschus manihot flowers is a first-order process with the passive diffusion mechanism. The absorption rates of each of flavonoids are significantly different. The absorption rate of flavonoid glycoside was lower than that of aglycone; the flavonoids from Abelmoschus manihot flowers could be absorbed in all of the intestinal segments. The best parts of intestine to absorb hyperoside and myricetin are jejunum and duodenum, separately. Verapamil could enhance the absorption of isoquercitrin, hyperoside, myricetin and quercetin-3'-O-glucoside by inhibiting P-glycoprotein (P-gp) drug efflux pump. PMID:21751500

Xue, Cai-fu; Guo, Jian-ming; Qian, Da-wei; Duan, Jin-ao; Shu, Yan

2011-04-01

77

Antimetastatic activity isolated from Colocasia esculenta (Taro)  

PubMed Central

Breast cancer mortality is primarily due to the occurrence of metastatic disease. We have identified a novel potential therapeutic agent derived from an edible root of the plant Colocasia esculenta, commonly known as taro, that has demonstrable activity in a preclinical model of metastatic breast cancer and that should have minimal toxicity. We have shown for the first time that a water-soluble extract of taro (TE) potently inhibits lung colonizing ability as well as spontaneous metastasis from mammary gland-implanted tumors, in a murine model of highly metastatic ER, PR and Her-2/neu negative breast cancer. TE modestly inhibits proliferation of some, but not all, breast and prostate cancer cell lines. Morphologic changes including cell rounding were observed. Tumor cell migration was completely blocked by TE. TE treatment also inhibited prostaglandin E2 (PGE2) synthesis and downregulated cyclooxygenase (COX) 1 and 2 mRNA expression. We purified the active compound(s) to near homogeneity with antimetastatic activity comparable to stock TE. The active compound with a native size of approximately 25 kD contains two fragments of nearly equal size. The N-terminal amino acid sequencing of both fragments reveals that the active compound is highly related to three taro proteins; 12 kD storage protein, tarin and lectin. All are similar in terms of amino acid sequence, post-translational processing and all contain a carbohydrate-binding domain. This is the first report describing a compound(s) derived from taro, that potently and specifically inhibits tumor metastasis.

Kundu, Namita; Campbell, Patricia; Hampton, Brian; Lin, Chen-Yong; Ma, Xinrong; Ambulos, Nicholas; Zhao, X. Frank; Goloubeva, Olga; Holt, Dawn; Fulton, Amy M.

2013-01-01

78

Biogene Amine im Gehirn vom Frosch ( Rana esculenta )  

Microsoft Academic Search

The distribution of biogenic amines in the central nervous system of Rana esculenta was investigated by means of the fluorescence-microscopical detection of catecholand tryptamines. The nucleus reticularis mesencephali was found to contain numerous neurones rich in catechol- and tryptamines. Apart from this nucleus nerve cells in the organon vasculosum hypothalami and in the area praeoptica were found to contain catecholamines.

H. Braak

1970-01-01

79

Makomotindoline from Makomotake, Zizania latifolia infected with Ustilago esculenta.  

PubMed

Makomotindoline (1) was isolated from Makomotake, Zizania latifolia infected with Ustilago esculenta. The structure was determined by the interpretation of spectroscopic data and synthesis. Makomotindoline (1), its l-Glc isomer (2) and its aglycon (3) were synthesized and their effects on rat glioma cells showed adverse effects on the cell growth. PMID:22672800

Suzuki, Tomohiro; Choi, Jae-Hoon; Kawaguchi, Takumi; Yamashita, Kimiko; Morita, Akio; Hirai, Hirofumi; Nagai, Kaoru; Hirose, Tomoyasu; Omura, Satoshi; Sunazuka, Toshiaki; Kawagishi, Hirokazu

2012-05-17

80

Genetic control of LDH isozymes in the Rana esculenta complex  

Microsoft Academic Search

Summary Studies of LDH isozymes in the European green frogs showed that the synthesis of the B subunits is controlled by 3 alleles at a single genetic locus. The genetic evidence supports the hypothesis thatRana esculenta is the hybrid ofR. lessonae x R. ridibunda.

P. Vogel; P. S. Chen

1976-01-01

81

Male vocalization and female choice in the hybridogenetic Rana lessonae\\/Rana esculenta complex  

Microsoft Academic Search

In many species, females can improve their fitness by preferring particular males over others. In Palaearctic water frogs of the Rana lessonae\\/R.esculenta complex the consequences of such mate choice are particularly pronounced. To produce viable offspring, the hybrid R.esculenta (genotype RL) must mate with the parental species R.lessonae (LL); but R.lessonae should avoid mating withR.esculenta , because the resulting hybrid

Marzia Roesli; Heinz-Ulrich Reyer

2000-01-01

82

Evolutionary history of the hybridogenetic hybrid frog Rana esculenta as deduced from mtDNA analyses.  

PubMed

mtDNA of the hybridogenetic hybrid frog Rana esculenta from Switzerland, Austria, and Poland was compared to mtDNA of the parental species R. ridibunda and R. lessonae using electrophoretic analysis of restriction enzyme fragments. Two mtDNA phenotypes, with 3.4% sequence divergence, are present in R. lessonae: type C is found in Poland, and type D is found in Switzerland. Rana ridibunda from Poland has either of two mtDNA phenotypes: type A is the typical ridibunda mtDNA, and type B is a lessonae mitochondrial genome, introgressed into R. ridibunda, that differs from type C mtDNA of R. lessonae by only 0.3%. Each of the three lessonae genomes differs from A, the typical ridibunda mtDNA, by approximately 8%. All four types of mtDNA (A and B of R. ridibunda, C and D of R. lessonae) are found in R. esculenta. Of 62 R. esculenta from Poland, 58 had type C, three had type A, and one had type B mtDNA. All nine R. esculenta from Switzerland had type D mtDNA. All three R. esculenta from Austria, from a population in which males of R. esculenta are rare, had ridibunda mtDNA, two having type B and one having type A. Both field observations and studies of mating preference indicate that the primary hybridizations that produce R. esculenta are between R. ridibunda females and R. lessonae males; thereafter, R. esculenta lineages are usually maintained by matings of R. esculenta females with R. lessonae males. The presence of ridibunda mtDNA in the three R. esculenta sampled from Austria, its occasional presence in R. esculenta populations in Poland, and its absence from R. esculenta in Switzerland support both the direction of the original hybridization and the rarity of formation of new R. esculenta lineages. The preponderance of R. esculenta individuals with lessonae mtDNA in our samples from central Europe suggests that most lineages have gone through at least one mating between an R. lessonae female and an R. esculenta male. This reveals a greater reproductive role for R. esculenta males than their partial sterility and infrequent matings would suggest. PMID:2832687

Spolsky, C; Uzzell, T

1986-01-01

83

Joint toxicity of methamidophos and cadmium acting on Abelmoschus manihot.  

PubMed

Joint toxicity of methamidophos and cadmium (Cd) on the ornamental Abelmoschus manihot was firstly examined and compared with single-factor effects of the two pollutants using ecotoxicological indexes including the inhibitory rate of seed germination, root elongation and inhibitory concentration 50% (IC50). The results indicated that methamidophos and Cd had unobvious( p > 0.05) effects on seed germination of the ornamental. There were significant( p < 0.05) inhibitory effects of Cd on root elongation of the tested plant. When the concentration of added Cd was low( < 20 mg/L), significant antagonistic effects on root elongation were observed. And synergic effects were observed when Cd was added in high dose( > 20 mg/L). However, the analysis of joint effects indicated that there were antagonistic effects between Cd and methamidophos under all the treatments. At the high concentration of Cd, joint toxicity of methamidophos and Cd was more dependent on concentration of Cd. PMID:16083107

Wang, Xiao-Fei; Zhou, Qi-Xing

2005-01-01

84

Kinetic characteristics of photoassimilate translocation in Alaria esculenta (Laminariales, Phaeophyceae)  

Microsoft Academic Search

The kinetics of translocation of 14C-labeled photoassimilate were studied in the kelp, Alaria esculenta (L.) Grev., using a Geiger-Müller detector-probe to measure radioactivity in the source and sink regions of dumbbell-shaped explants cut from blades. Rapid tracer efflux from the source occurred for 4 days following a pulse of [14C]bicarbonate, with 40–60% of the initial activity remaining in the source

Richard G. Buggeln; Steven Lucken

1979-01-01

85

Identification, cloning, and characterization of ?-glucosidase from Ustilago esculenta  

Microsoft Academic Search

Hydrolytic enzymes responsible for laminarin degradation were found to be secreted during growth of Ustilago esculenta on laminarin. An enzyme involved in laminarin degradation was purified by assaying release of glucose from laminaribiose.\\u000a Ion-exchange chromatography of the culture filtrate followed by size-exclusion chromatography yielded a 110-kDa protein associated\\u000a with laminaribiose hydrolysis. LC\\/MS\\/MS analysis of the 110-kDa protein identified three peptide

Masahiro Nakajima; Tetsuro Yamashita; Machiko Takahashi; Yuki Nakano; Takumi Takeda

86

Zizania latifolia and Ustilago esculenta , a Grass-Fungus Association  

Microsoft Academic Search

Zizania latifolia (Manchurian wild rice), native to eastern Asia, is often infected by the smut fungus, Ustilago esculenta, causing culm enlargement\\u000a and failure to produce flowers. The enlarged infected culms have been used as a vegetable (gau sun) in China since the 10th century. The occasionally-used nameZ. Caduciflora is shown to be only a synonym. To facilitate identification of the

E. E. Terrell; L. R. Batra

1982-01-01

87

Identification, cloning, and characterization of ?-glucosidase from Ustilago esculenta.  

PubMed

Hydrolytic enzymes responsible for laminarin degradation were found to be secreted during growth of Ustilago esculenta on laminarin. An enzyme involved in laminarin degradation was purified by assaying release of glucose from laminaribiose. Ion-exchange chromatography of the culture filtrate followed by size-exclusion chromatography yielded a 110-kDa protein associated with laminaribiose hydrolysis. LC/MS/MS analysis of the 110-kDa protein identified three peptide sequences that shared significant similarity with a putative glucoside hydrolase family (GH) 3 ?-glucosidase in Ustilago maydis. Based on the DNA sequence of the U. maydis GH3 ?-glucosidase, a gene encoding a putative GH3 ?-glucosidase in U. esculenta (Uebgl3A) was cloned by PCR. Based on the deduced amino acid sequence, the protein encoded by Uebgl3A has a molecular mass of 91 kDa and shares 90% identity with U. maydis GH3 ?-glucosidase. Recombinant UeBgl3A expressed in Aspergillus oryzae released glucose from ?-1,3-, ?-1,4-, and ?-1,6-linked oligosaccharides, and from 1,3-1,4-?-glucan and laminarin polysaccharides, indicating that UeBgl3A is a ?-glucosidase. Kinetic analysis showed that UeBgl3A preferentially hydrolyzed laminaritriose and laminaritetraose. These results suggest that UeBgl3A is a key enzyme that produces glucose from laminarioligosaccharides during growth of U. esculenta on laminarin. PMID:21850431

Nakajima, Masahiro; Yamashita, Tetsuro; Takahashi, Machiko; Nakano, Yuki; Takeda, Takumi

2011-08-18

88

Patterns of protein synthesis in oocytes and early embryos of Rana esculenta complex  

Microsoft Academic Search

We have used isotopic labelling and both one-and two-dimensional electrophoretic procedures to analyse the protien synthesis patterns in oocytes and early embryos of three phenotypes of the European green frogs. The results demonstrated that protein patterns of Rana ridibunda and R. esculenta are identical, but that they differ from those of R. lessonae. Progeny of the lethal cross R. esculenta

P. S. Chen; E. Stumm-Zollinger

1986-01-01

89

Are North Atlantic Alaria esculenta and A. grandifolia (Alariaceae, Phaeophyceae) conspecific?  

Microsoft Academic Search

Alaria (Alariaceae, Phaeophyceae) is a common genus of kelps in the northern hemisphere. Fourteen species are currently recognized, of which three, Alaria esculenta (L.) Greville, A. pylaii (Bory de Saint-Vincent) Greville and A. grandifolia J. Agardh, are reported for the coldtemperate North Atlantic Ocean. Alaria esculenta, the type species described originally from the North Atlantic, exhibits a range of biogeographically

Stefan Kraan; Jan Rueness; Michael Guiry

2001-01-01

90

Cytology and ultrastructure of interactions between Ustilago esculenta and Zizania latifolia  

Microsoft Academic Search

Ustilago esculenta is a biotrophic smut fungus that parasitizes Zizania latifolia, an edible aquatic vegetable of the southern China region. Infection results in swelling of the upper parts of the Z. latifolia culm which are called jiaobai and have a unique flavor and delicacy and are popular among Chinese. The infection process of Z. latifolia by U. esculenta was investigated

Jing-Ze Zhang; Fu-Qiang Chu; De-Ping Guo; Kevin D. Hyde; Guang-Lin Xie

91

Preventive effect of Abelmoschus manihot (L.) Medik. on bone loss in the ovariectomised rats.  

PubMed

Because the biggest culprit in pathogenesis of osteoporosis is oestrogen deficiency, hormone replacement therapy remained the mainstay for prevention. However most of postmenopausal women are more inclined to use natural alternative. We thus investigated the ability of Abelmoschus manihot, a herbal medicine to prevent bone loss in ovariectomised rats. Female Wistar rats were sham operated (SH: 8) or ovariectomised (OVX: 24). On day 0, OVX rats were randomly assigned to groups as follows: eight received 10% Abelmoschus manihot leaves in their diet, eight were given 15% Abelmoschus manihot leaves and eight were untreated (OVX). Compounds were mixed with a soy protein-free diet and given orally for 3 months. At necropsy, bone mineral density (BMD) in the femur and in its metaphyseal zone was lower in OVX than SH (p<0.05). This osteopenia was prevented by consumption of the highest dose of Abelmoschus manihot leaves. Bone mineral content (BMC) in the total femur and its metaphyseal and diaphyseal subregions was improved, as well (p<0.05). This could be explained by a trend towards decreased bone resorption. The lowest dose did not elicit any significant effect. In conclusion, Abelmoschus manihot consumption, at the dose of 15% in the diet, provided bone-sparing effects by improving both BMD and BMC. PMID:15848020

Puel, C; Mathey, J; Kati-Coulibaly, S; Davicco, M J; Lebecque, P; Chanteranne, B; Horcajada, M N; Coxam, V

2005-05-13

92

Determination of molecular weights and monosaccharide compositions in Abelmoschus manihot polysaccharides  

NASA Astrophysics Data System (ADS)

Abelmoschus manihot polysaccharide, AMP-1, AMP-2, AMP-3, and AMP-4, were purified from four kinds of Abelmoschus manihot gum (AMG). The molecular weights and monosaccharide compositions of AMP-1, AMP-2, AMP-3 and AMP-4 were characterized by gel permeation chromatography, Fourier transform-infrared spectroscopy and high performance anion-exchange chromatography with pulsed amperometric detection. Results indicated that the molecular weights of AMP-1, AMP-2, AMP-3, and AMP-4 were approximately 3.91 × 103, 5.36 × 105, 3.87 × 103, and 5.12 × 105 Da, respectively. The Abelmoschus manihot polysaccharide was mainly composed of galactose, glucose and mannose with the molar ratios at 0.29: 1.00: 0.41 (AMP-1), 0.56: 0.13: 1.00 (AMP-2), 0.10: 1.00: 0.11 (AMP-3) and 0.55: 0.17: 1.00 (AMP-4), respectively.

Wang, Xuemei; Wang, Yingying; Wu, Mimi; Zhang, Xiuzhen

2012-09-01

93

Morphological and molecular differences in two strains of Ustilago esculenta.  

PubMed

Ustilago esculenta is a fungal endophyte of Zizania latifolia that plays an important agricultural role in this vegetable crop. The purpose of this study was to characterize sporidial (T) and mycelial (M-T) strains of U. esculenta isolated from sporulating and non-sporulating galls on plants growing in Zhejiang province, China. Morphological comparisons of the T strain and M-T strain were made by optical and scanning electron microscope observation. Genetic differences were examined by sequencing the ITS region of the fungus and examining differential protein expression by two-dimensional gel electrophoresis and MALDI-TOF-MS/MS. The sporidial (T) and mycelial (M-T) strains differed in morphological characteristics of their in vitro single colony formations and in cell shape. Alignment of ITS sequences of the T strain and M-T strain revealed a single mutation between the T strain and M-T strain, but the sequences were the same within strains. A total of 146 proteins were only expressed in the M-T strain, and 242 proteins were only expressed in the T strain isolated from infected plants. A total of 222 proteins were up-regulated or down-regulated in the T strain when compared with the M-T strain. Of these, 18 proteins were identified and eight were associated with processes involving energy metabolism and the cytoskeleton. Two morphology-related proteins, MAP kinase kinase and actin, were differentially expressed. The differences noted in the T strain and M-T strain may lead to a better understanding of the life cycle and morphogenesis in U. esculenta. PMID:20495805

You, Wenyu; Liu, Qian; Zou, Keqin; Yu, Xiaoping; Cui, Haifeng; Ye, Zihong

2010-05-21

94

Feeding potential of cassava (Manihot esculenta Crantz) peels ensiled with Leucaena leucocephala and Gliricidia sepium assessed with West African dwarf goats.  

PubMed

Cassava peels (CaPe) were ensiled in mixtures with Gliricidia sepium and Leucaena leucocephala, and the utilization of the mixed silages by West African dwarf (WAD) goats was assessed. Five silages were composed, comprising of 100% ensiled CaPe (control), CaPe + G. sepium 2:1 (w/w; 2CGS), CaPe + G. sepium 1:1 (w/w; CGS), CaPe + L. leucocephala 2:1 (w/w; 2CLL) and CaPe + L. leucocephala 1:1 (w/w; CLL). All diets were supplemented with molasses (40 g/kg) before ensiling which lasted 3 months. Fifteen WAD goats (8.01 ± 0.12 kg body weight) were fed one of the experimental diets (50 g/kg body weight) for 8 weeks. The control had the lowest hydrocyanic acid content (0.05 mg/kg DM), while others ranged from 6.2 to 81.3 mg/kg. Condensed tannin concentration ranged from 1.7 to 8.4 mg/kg DM, while mimosine levels were 11.6 and 12.4 mg/kg DM in 2CLL and CLL, respectively. After fermentation, all silages showed low pH (<4.5) and were different (P < 0.05) in the lactic, acetic and butyric acid concentrations. Ratio of foliage supplementation influenced DM intake (P < 0.05). Daily weight gains ranged from 17 (CLL) to 24 g/day in control. The digestibility coefficients of nutrients and fibre fractions differed (P < 0.05) among diets. The values for packed cell volume, haemoglobin, red blood cells, neutrophils, lymphocytes and monocytes were also different (P < 0.05) across the dietary treatments. Ensiling CaPe with foliages of G. sepium and L. leucocephala can be recommended for feeding WAD goats especially during the dry spells when there is little or no available forage for the animals. PMID:23397521

Oduguwa, Bamidele Omonuwa; Oni, Adebayo Olusoji; Arigbede, Oluwasanmi Moses; Adesunbola, Julius Olukunle; Sudekum, Karl Heinz

2013-02-10

95

Spatial patterns of diversity and genetic erosion of traditional cassava ( Manihot esculenta Crantz) in the Peruvian Amazon: An evaluation of socio-economic and environmental indicators  

Microsoft Academic Search

This study evaluates quantitatively the suitability of the use of site-specific socio-economic and environmental data as indicators\\u000a to rapidly assess patterns of diversity and genetic erosion risk in cassava. Socio-economic data as well as farmers’ estimation\\u000a of genetic erosion were collected in the study area, the Ucayali region of the Peruvian Amazon, through interviews with 285\\u000a cassava farmers in 50

Louise Willemen; Xavier Scheldeman; Víctor Soto Cabellos; Simón Rafael Salazar; Luigi Guarino

2007-01-01

96

Germination ecology of Cassava ( Manihot esculenta Crantz, Euphorbiaceae) in traditional agroecosystems: Seed and seedling biology of a vegetatively propagated domesticated plant  

Microsoft Academic Search

Cassava is clonally propagated, but Amerindian farmers also use plants from volunteer seedlings to prepare stem cuttings.\\u000a Although sexual reproduction plays a role in cassava’s evolution it is poorly studied. We examined one aspect of cassava reproductive\\u000a ecology, seed dormancy and germination. Volunteer seedlings emerge from a soil bank of seeds produced during the previous\\u000a cycle of cultivation that remain

Benoît Pujol; Guillaume Gigot; Gérard Laurent; Marina Pinheiro-Kluppel; Marianne Elias; Martine Hossaert-McKey; Doyle McKey

2002-01-01

97

Expression pattern conferred by a glutamic acid-rich protein gene promoter in field-grown transgenic cassava (Manihot esculenta Crantz).  

PubMed

A major constraint for incorporating new traits into cassava using biotechnology is the limited list of known/tested promoters that encourage the expression of transgenes in the cassava's starchy roots. Based on a previous report on the glutamic-acid-rich protein Pt2L4, indicating a preferential expression in roots, we cloned the corresponding gene including promoter sequence. A promoter fragment (CP2; 731 bp) was evaluated for its potential to regulate the expression of the reporter gene GUSPlus in transgenic cassava plants grown in the field. Intense GUS staining was observed in storage roots and vascular stem tissues; less intense staining in leaves; and none in the pith. Consistent with determined mRNA levels of the GUSPlus gene, fluorometric analyses revealed equal activities in root pulp and stems, but 3.5 times less in leaves. In a second approach, the activity of a longer promoter fragment (CP1) including an intrinsic intron was evaluated in carrot plants. CP1 exhibited a pronounced tissue preference, conferring high expression in the secondary phloem and vascular cambium of roots, but six times lower expression levels in leaf vascular tissues. Thus, CP1 and CP2 may be useful tools to improve nutritional and agronomical traits of cassava by genetic engineering. To date, this is the first study presenting field data on the specificity and potential of promoters for transgenic cassava. PMID:20336312

Beltrán, J; Prías, M; Al-Babili, S; Ladino, Y; López, D; Beyer, P; Chavarriaga, P; Tohme, J

2010-03-25

98

Studies on variation of carotenoid-proteins content in Cassava (Manihot esculenta Crantz) storage root reveal implications for breeding and the use of induced mutations  

Technology Transfer Automated Retrieval System (TEKTRAN)

Protein content in storage roots of cassava is low but variable and characterization of this variability is lacking. Total buffer extractable proteins (TBEP) content in pigmented cassava landraces varied from 0.9-7.5 (mg/gDWt.) and correlated with total carotenoid content (R2=0.4757). More than 3x T...

99

Simple sequence repeat (SSR) markers survey of the cassava (Manihot esculenta Crantz) genome: towards an SSR-based molecular genetic map of cassava  

Microsoft Academic Search

The development of PCR-based, easily automated molecular genetic markers, such as SSR markers, are required for realistic\\u000a cost-effective marker-assisted selection schemes. This paper describes the development and characterization of 172 new SSR\\u000a markers for the cassava genome. The placement of 36 of these markers on the existing RFLP framework map of cassava is also\\u000a reported. Two similar enrichment methods were

P. Stephenson; K. Edwards; S. Melzer; J. Nkumbira; U. Gullberg; K. Apel; M. Gale; J. Tohme; M. Fregene

2001-01-01

100

Unmanaged sexual reproduction and the dynamics of genetic diversity of a vegetatively propagated crop plant, cassava (Manihot esculenta Crantz), in a traditional farming system  

Microsoft Academic Search

Occurrence of intervarietal or interspecific natural crosses has been reported for many crop plants in traditional farming systems, underlining the potential importance of this source of genetic exchange for the dynamics of genetic diversity of crop plants. In this study, we use microsatellite loci to investigate the role of volunteer seedlings (plants originating from unmanaged sexual reproduction) in the dynamics

M. Elias; L. Penet; P. Vindry; D. McKey; O. Panaud; T. Robert

2001-01-01

101

Anti-allergic Activity of Stem Bark of Myrica esculenta Buch.-Ham. (Myricaceae)  

PubMed Central

Allergic diseases, such as allergic asthma, are hypersensitivity reactions initiated by immunological mechanisms. Myrica esculenta (M. esculenta) is known traditionally in Ayurveda to possess anti-asthmatic activity. The present investigation was undertaken to evaluate the effect of crude extract of stem bark of M. esculenta (Family Myricaceae, commonly known as Kaiphal) on experimental allergic reactions. Experimental models studied were allergic pleurisy and vascular permeability induced by acetic acid in mice. Pretreatment with M. esculenta (75 mg/kg and 150 mg/kg, p.o.) significantly inhibited the eosinophil accumulation (P < 0.01) respectively in the pleural cavity. M. esculenta (75 and 150 mg/kg, p.o.) significantly inhibited the rise in plasma exudation (57.12% and 59.77%, P < 0.01) induced by acetic acid in mice. These findings demonstrate that the crude extract from the stem bark of M. esculenta possesses antiallergic activity. This activity may be mediated by reducing the release of mediators such as histamine, inhibition of mast cell degranulation, and inhibition of eosinophil accumulation thereby preventing the release of cytokines and chemokines.

Patel, KG; Rao, NJ; Gajera, VG; Bhatt, PA; Patel, KV; Gandhi, TR

2010-01-01

102

Anti-allergic Activity of Stem Bark of Myrica esculenta Buch.-Ham. (Myricaceae).  

PubMed

Allergic diseases, such as allergic asthma, are hypersensitivity reactions initiated by immunological mechanisms. Myrica esculenta (M. esculenta) is known traditionally in Ayurveda to possess anti-asthmatic activity. The present investigation was undertaken to evaluate the effect of crude extract of stem bark of M. esculenta (Family Myricaceae, commonly known as Kaiphal) on experimental allergic reactions. Experimental models studied were allergic pleurisy and vascular permeability induced by acetic acid in mice. Pretreatment with M. esculenta (75 mg/kg and 150 mg/kg, p.o.) significantly inhibited the eosinophil accumulation (P < 0.01) respectively in the pleural cavity. M. esculenta (75 and 150 mg/kg, p.o.) significantly inhibited the rise in plasma exudation (57.12% and 59.77%, P < 0.01) induced by acetic acid in mice. These findings demonstrate that the crude extract from the stem bark of M. esculenta possesses antiallergic activity. This activity may be mediated by reducing the release of mediators such as histamine, inhibition of mast cell degranulation, and inhibition of eosinophil accumulation thereby preventing the release of cytokines and chemokines. PMID:21331196

Patel, Kg; Rao, Nj; Gajera, Vg; Bhatt, Pa; Patel, Kv; Gandhi, Tr

2010-01-01

103

[Mechanisms and effects of Abelmoschus manihot preparations in treating chronic kidney disease].  

PubMed

Abelmoschus manihot (AM) is a medicinal plant rich in twenty kinds of separated active bio-components including flavones, polysaccharides, trannic acid, and long chain hydrocarbons. Among these, total flavones of A. manihot (TFA) are the major active component. In this review, the mechanisms of Huangkui capsule will be discussed as a preparation of AM to treat chronic kidney disease (CKD) by improving immunological reaction, inflammation, renal fibrosis, and renal tubular epithelial injury. Additionally, it has been reported that Huangkui capsule can ameliorate some clinical symptoms, proteinuria, hematuria, and renal function in patients with common CKD, such as nephrotic syndrome, diabetic nephropathy, Henoch-Schönlein purpura nephritis, IgA nephropathy, and membranous nephropathy. PMID:23189729

Chen, Ping; Wan, Yigang; Wang, Chaojun; Zhao, Qing; Wei, Qingxue; Tu, Yue; Yin, Xuejiao

2012-08-01

104

An Acid Phosphatase from Manihot glaziovii as an Alternative to Alkaline Phosphatase for Molecular Cloning Experiments  

Microsoft Academic Search

An acid phosphatase, free of deoxyribonuclease activity, was isolated from Manihot glaziovii leaves. It had a Mr of 78 kDa and was optimally active at pH 4.3 and 52 °C. It was inactivated at 65 °C over 15 min. It had a broad substrate specificity with strongest activity towards p-nitrophenyl phosphate. The enzyme dephosphorylated linearized pUC18 DNA and preventing self-ligation under the same conditions

S. C. Tham; S. H. Lim; H. H. Yeoh

2005-01-01

105

Simultaneous determination of seven active flavonols in the flowers of Abelmoschus manihot by HPLC.  

PubMed

A high-performance liquid chromatography method is developed for the simultaneous quantification of seven flavonols, namely quercetin-3-O-robinobioside, hyperin, isoquercetin, hibifolin, myricetin, quercetin-3'-O-glucoside, and quercetin, in the flower of Abelmoschus manihot. These seven flavonols are selected as chemical markers because they are the major pharmacologically active constituents in the flower. The method involves the use of a Thermo ODS-2HYEPRSIL reversed-phase column (5 microm, 250 x 4.6 mm) at 25 degrees C with a mixture of acetonitrile and aqueous H(3)PO(4) as the mobile phase and detection at 370 nm. The recovery of the method is 94.31-107.08% with an RSD < or = 3.14% and the linearity (r(2) > 0.9996) is obtained for all the flavonoids. The current assay method can be readily utilized for the determination of the flavonols present in the flower and is considered to be suitable for the quality control of A. manihot samples. The comparison of flowers collected from nine locations shows that flavonoid glucoside is more stable than aglycon in the flower. This is the first study that analyzes the stability of flavonoids in the flower of A. manihot. This research also provides important evidence that the flower is a potentially abundant resource for obtaining hibifolin. PMID:19298707

Lai, Xianyin; Liang, Hong; Zhao, Yuying; Wang, Bin

2009-03-01

106

Atrazine increases the sodium absorption in frog (Rana esculenta) skin.  

PubMed

The presence of atrazine in agricultural sites has been linked to the decline in amphibian populations. The efforts of the scientific community generally are directed toward investigating the long-term effect of atrazine on complex functions (reproduction or respiration), but in the present study, we investigated the short-term effect on the short-circuit current (I(sc)), a quantitative measure of the ion transport operated by frog (Rana esculenta) skin. Treatment with 5 microM atrazine (1.08 mg/L) does not affect the transepithelial outfluxes of [14C]mannitol or [14C]urea; therefore, atrazine does not damage the barrier properties of frog skin. Atrazine causes a dose-dependent increase in the short-circuit current, with a minimum of 4.64 +/- 0.76 microA/cm2 (11.05% +/- 1.22%) and a maximum of 12.7 +/- 0.7 microA/cm2 (35% +/- 2.4%) measured at 10 nM and 5 microM, respectively. An increase in Isc also is caused by 5 microM ametryne, prometryn, simazine, terbuthylazine, or terbutryn (other atrazine derivatives). In particular, atrazine increases the transepithelial 22Na+ influx without affecting the outflux. Finally, stimulation of Isc by atrazine is suppressed by SQ 22536, H89, U73122, 2-aminoethoxydiphenyl borate, and W7 (blockers of adenylate cyclase, protein kinase A, phospholipase C, intracellular Ca2+ increase, and calmodulin, respectively), whereas indomethacin and calphostin C (inhibitors of cyclooxygenase and protein kinase C, respectively) have no effect. PMID:16519313

Cassano, Giuseppe; Bellantuono, Vito; Ardizzone, Concetta; Lippe, Claudio

2006-02-01

107

Survival in adults of the water frog Rana lessonae and its hybridogenetic associate Rana esculenta  

Microsoft Academic Search

Using recent developments in capture-mark-recapture modelling, I analysed survival rates of adults of two species of water frogs, the parent species Rana lessonae and its sexual parasite, the hybrid Rana esculenta. Frogs were caught in four different breeding ponds between 1995 and 1998 and the effects of genotype (= species), sex, pond, and time on survival rates and recapture probabilities

Anna-Katherina Holenweg Peter

2001-01-01

108

Biosynthesis of Indole3Acetic Acid by the Gall-inducing Fungus Ustilago esculenta  

Microsoft Academic Search

Ustilago esculenta incites the formation of an edible gall and prevents inflorescence and seed production in the aquatic perennial grass, Zizania latifolia. As compared to the healthy tissues, the edible galls had higher amounts of indole-3-acetic acid (IAA), which could be synthesized from the host plant and\\/or the fungal pathogen. In this study we investigated the ability for IAA production

2004-01-01

109

NADPH-diaphorase-positive neurons and pathways in the brain of the frog Rana esculenta  

Microsoft Academic Search

We described the NADPH-diaphorase-containing neurons and fibres in the brain of the frog Rana esculenta. In the telencephalon stained cells occurred in the olfactory bulb, all subdivisions of the pallium, the diagonal band, the medial septum and the striatum. The olfactory glomeruli showed the most intense enzyme reaction. The neuropil of the accessory olfactory bulb was also heavily stained and

G. Lázár; Attila Losonczy

1999-01-01

110

Arsenic, cadmium, and mercury in cocoyam (Xanthosoma sagititolium) and watercocoyam (Colocasia esculenta) in Tarkwa a mining community.  

PubMed

Cocoyam (Xanthosoma sagititolium) and Watercocoyam (Colocasia esculenta) have gained increased importance in the diets of majority of people in developing countries such as Ghana. The concentration levels of arsenic, cadmium, and mercury in Cocoyam (X. sagititolium) and Watercocoyam (C. esculenta) in Tarkwa and its surrounding villages a mining community in Ghana were measured in this study. From the results of the study, the levels of arsenic, cadmium and mercury in X. sagititolium and C. esculenta were higher than the WHO recommended levels. These root tubers absorb or uptake toxic chemicals from the soil as a result of the mining operations. This means that, the consumption of X. sagititolium and C. esculenta by humans from such environments may pose a serious health risk. There is therefore the need for a concerted effort by all to minimize the negative impact of gold mining in the study area. PMID:17673943

Essumang, D K; Dodoo, D K; Obiri, S; Yaney, J Y

2007-08-03

111

[Clinical observation on diabetic nephropathy treated with alcohol of Abelmoschus manihot].  

PubMed

Sixty-eight cases of non-insulin dependent diabetes mellitus (NIDDM) complicated with nephropathy were randomly divided into two groups: treated group, 35 cases treated with alcohol extraction of Abelmoschus manihot, Gliclazide and Captopril tablets; control group, 33 cases treated with Gliclazide and Captopril tablets, over a period of 8 weeks. The total effective rate in treated and control group were 83.87% and 31.03%(P < 0.01), urinary micro-albumin were 31.7 mg/L and 76.3 mg/L (P < 0.05), proteinuria were 0.41 g/24h and 0.77 g/24h (P < 0.01), blood beta 2-microglobulin were 3317.8 ng/ml and 3473.1 ng/ml (P < 0.05), urinary beta 2-microglobulin were 367.2 ng/ml and 641.5 ng/ml (P < 0.01), urinary N-acetyl-beta-glucosaminidase (NAG) were 26.3 u/L and 66.7 u/L (P < 0.01), plasma lipid peroxide (LPO) were 6.13 nmol/L and 8.78 nmol/L (P < 0.05), and plasma superoxide anion were 8.36 kcpm and 10.42 kcpm respectively (P < 0.05). It was suggested that Abemoschus manihot alcohol extraction could eliminate oxygen free radicals, alleviate renal tubular-interstitial diseases, improve renal function and reduce proteinuria. PMID:7640495

Yu, J Y; Xiong, N N; Guo, H F

1995-05-01

112

Interactive effects of radiation, temperature and salinity on different life history stages of the Arctic kelp Alaria esculenta (Phaeophyceae)  

Microsoft Academic Search

To estimate the potential effects of climate change on polar marine macroalgae, studies on interactive stress effects of multiple\\u000a climate-related parameters are essential. Interactions of temperature, radiation and salinity on two different life history\\u000a stages of Alaria esculenta (L.) Greville from the Kongsfjord (Spitsbergen) were investigated for the first time within this study. Adult macroscopic\\u000a sporophytes of A. esculenta were

Jana Fredersdorf; Ruth Müller; Susanne Becker; Christian Wiencke; Kai Bischof

2009-01-01

113

[A case of hypersensitivity pneumonitis caused by smut spores of Ustilago esculenta].  

PubMed

A 49-year-old woman was admitted with cough, general fatigue, and dyspnea on effort. Her hobby was the Japanese traditional handicraft of lacquer-carving. She sometimes used smut spores of Ustilago esculenta, pronounced as "Makomozumi"on lacquer ware. The chest radiographs showed diffuse ground-glass opacities and small centrilobular nodules. Bronchoalveolar lavage yielded a marked number of lymphocytes as well as total cell counts and a low CD4 +/CD8 + ratio. The transbronchial lung biopsy specimen revealed lymphocytic alveolitis and non-necrotizing epithelioid cell granulomas. The results of provocation test by Makomozumi were positive. Serum tests of the specific antibody against extracted soluble antigens of smut spores were positive. The peripheral lymphocyte proliferation test, performed with Mokomozumi antigens was also positive. The final diagnosis was hypersensitivity pneumonitis induced by smut spores of fungus Ustilago esculenta. PMID:17491314

Fujii, Yumi; Usui, Yutaka; Konno, Kazunori; Atarashi, Kenichi; Ohtani, Yoshio; Inase, Naohiko; Tanaka, Takehiko; Yoshizawa, Yasuyuki

2007-04-01

114

Genetic diversity in Taro ( Colocasia esculenta Schott, Araceae) in China: An ethnobotanical and genetic approach  

Microsoft Academic Search

Taro,Colocasia esculenta (Araceae), is a widely distributed and important food crop in the humid tropics and subtropics. Relatively neglected by science,\\u000a much knowledge of genetic diversity in taro is with farmers. Taro genetic resources managed by five ethnic communities and\\u000a Han farming villages in diverse ecosystems were sampled and characterized in Yunnan Province, southwest China. This study\\u000a documented a new

Xu Jianchu; Yang Yongping; Pu Yingdong; W. G. Ayad; P. B. Eyzaguirre

2001-01-01

115

Distribution of somatostatin-like immunoreactivity in the brain of the frog, Rana esculenta, during development  

Microsoft Academic Search

The anatomical distribution of somatostatin-like immunoreactivity in the central nervous system of the frog, Rana esculenta, during development and in juvenile specimens was investigated by indirect immunofluorescence. Soon after hatching, at stages II-III, somatostatin-like immunoreactive structures were found in the preoptic-median eminence complex. In stage VI tadpoles, new groups of immunopositive perikarya and nerve fibers appeared in the diencephalon, within

Mauro Vallarino; Maura Mathieu; Biagio D'Aniello; Rakesh K Rastogi

1998-01-01

116

Detection and Identification of Dasheen mosaic virus Infecting Colocasia esculenta in India  

Microsoft Academic Search

Reverse transcription polymerase chain reaction of the infected leaf samples of Colocasia esculenta plants showing severe whitish feathery symptoms were carried out using Potyvirus group specific primers, resulting in an amplicon of 327 bp, encoding the core region of the coat protein gene. Sequencing\\u000a and BLAST analysis showed that the virus is distinct, closely related to Dasheen mosaic virus (DsMV). Sequence

Binoy Babu; Vinayaka Hegde; T. Makeshkumar; M. L. Jeeva

2011-01-01

117

The generic position of Ustilago maydis, Ustilago scitaminea , and Ustilago esculenta (Ustilaginales)  

Microsoft Academic Search

Three species of smut fungi (Ustilaginales, Basidiomycota) of economic importance, Ustilago maydis on corn, U. scitaminea on sugar cane, and U. esculenta on Zizania latifolia, were investigated in order to define their systematic position using morphological characteristics of the sori, ultrastructure\\u000a of teliospore walls, and molecular data of the LSU rDNA. LSU rDNA suggests that U. maydis and U. scitaminea

Meike Piepenbring; Matthias Stoll; Franz Oberwinkler

2002-01-01

118

Immunoreactive mammalian and chicken-II GnRHs in Rana esculenta brain during development  

Microsoft Academic Search

Two forms of gonadotropin-releasing hormone (mammalian, mGnRH and chicken-II, cGnRH-II) were measured by radioimmunoassay in the nasal area (containing peripheral terminal nerve), brain and pituitary of Rana esculenta during larval development, metamorphosis, and until prior to becoming reproductively active. Small amounts of both forms of GnRH were first detected in the brain extract of early tadpoles (stage 26–27, when hindlimbs

Maria M. Di Fiore; Judy A. King; Biagio D'Aniello; Rakesh K. Rastogi

1996-01-01

119

Alcuni aspetti delle cellule follicolari e della nuvola mitocondriale nell'ovogenesi di Rana synklepton esculenta  

Microsoft Academic Search

In this paper the presence of a novel protein, p27BBP and of cytokeratin were studied with an immunocytochemical approach in Rana synklepton esculenta oogenesis. It has been shown in mammals that p27BBP, is a constituent of the plasma membrane of malignant and normal epithelial cells, associated with the cytoplasmic tail of integrin ?4 and\\/or bound to intermediate filaments. p27BBP is

CAROTENUTO ROSA

120

Distribution of FMRFamide-like immunoreactivity in the brain and pituitary of Rana esculenta during development  

Microsoft Academic Search

Developmental aspects of the distribution of FMRFamide (Phe-Met-Arg-Phe-NH2) immunoreactivity (ir) were investigated by indirect immunofluorescence in the brain, pituitary and terminal nerve of the frog, Rana esculenta. Soon after hatching, FMRFamide neurons were found in the proximal terminal nerve, mediobasal olfactory bulb, caudal dorsolateral pallium, diagonal band of Broca, anterior preoptic area, suprachiasmatic area, thalamus, infundibulum, and developing pituitary. FMRFamide

Biagio D'Aniello; Maria Fiorentino; Claudia Pinelli; Maria di Meglio; Mauro Vallarino; Rakesh K. Rastogi

1996-01-01

121

Evidence of Batrachochytrium dendrobatidis Infection in Water Frogs of the Rana esculenta Complex in Central Italy  

Microsoft Academic Search

Batrachochytrium dendrobatidis (phylum Chytridiomycota, order Chytridiales) is the causative organism of chytridiomycosis in amphibians, a disease associated\\u000a with their population decline worldwide. In this work, we report a cutaneous infection in water frogs of the Rana esculenta complex in agricultural areas of Umbria, central Italy. Histological, immunohistochemical, ultrastructural, and molecular\\u000a analyses demonstrated for the first time the presence of the

Francesca Simoncelli; Anna Fagotti; Raffaele Dall’Olio; Daniela Vagnetti; Rita Pascolini; Ines Di Rosa

2005-01-01

122

Interactive effects of radiation, temperature and salinity on different life history stages of the Arctic kelp Alaria esculenta (Phaeophyceae).  

PubMed

To estimate the potential effects of climate change on polar marine macroalgae, studies on interactive stress effects of multiple climate-related parameters are essential. Interactions of temperature, radiation and salinity on two different life history stages of Alaria esculenta (L.) Greville from the Kongsfjord (Spitsbergen) were investigated for the first time within this study. Adult macroscopic sporophytes of A. esculenta were exposed to different temperatures between 4 and 21 degrees C combined with artificial irradiation conditions [photosynthetically active radiation, ultraviolet (UV) radiation: UV-A/UV-B, first experiment] and with different salinities [34, 28, 20 practical salinity units (p.s.u.) second experiment]. Effects of photosynthetic activity were determined by measuring variable chlorophyll fluorescence of photosystem II. Germination success of young microscopic zoospores of A. esculenta was studied under multifactorial stress. Zoospore suspensions were exposed to the three different salinities and irradiation conditions at four temperatures between 2 and 16 degrees C. Overall, A. esculenta exhibited a highly stage-specific susceptibility towards the experimental treatments. In both experiments using sporophytes, photosynthetic activity showed significant temperature effects and only very few significant radiation and salinity effects. Microscopic stages of A. esculenta were shown to be more sensitive than the adult macroscopic stages, since germination capacity of zoospores was significantly affected by temperature and salinity changes, and interactions of both. These results suggest that multiple stress factors interact synergistically. Temperature seems to be a predominant environmental parameter for the kelp A. esculenta. Overall, A. esculenta proved to be relatively tolerant and adaptable to increasing temperature and UV radiation, as well as to diluted salinities, but only up to a specific limit. PMID:19330357

Fredersdorf, Jana; Müller, Ruth; Becker, Susanne; Wiencke, Christian; Bischof, Kai

2009-03-29

123

Composition of oxalates in baked taro ( Colocasia esculenta var. Schott) leaves cooked alone or with additions of cows milk or coconut milk  

Microsoft Academic Search

Taro (Colocasia esculenta var. Schott) is a major staple food crop in parts of Asia and the Pacific Islands and two different cultivars of taro plants Taro Tonga (C. esculenta) and Taro Futuna (Xanthosoma sagittifolium), known respectively as Maori and Japanese, are grown as a minor crop in New Zealand. The leaves are either boiled or baked before they are

G. P. Savage; L. Mårtensson; J. R. Sedcole

2009-01-01

124

Some roles of methanol-soluble fraction of rubber from Manihot glaziovii. Part 1. Sitosterol and fatty acids  

Microsoft Academic Search

Summary  \\u000a \\u000a Manihot glaziovii rubber was dissolved in purified chloroform and coagulated with methanol. An oily like material (ACM) remaining from the\\u000a coagulation process was isolated and submitted to column chromatography over silica gel yielding several fractions. The components\\u000a of the major fraction, denoted collectively as F-GH, were isolated and characterised by FTIR, 1H and 13C NMR spectroscopies and GC\\/MS as

N. M. P. S. Ricardo; J. P. A. Feitosa; E. R. Silveira; M. Almeida Neto

2001-01-01

125

Anticonvulsant, antidepressant-like activity of Abelmoschus manihot ethanol extract and its potential active components in vivo.  

PubMed

Depression is the most common psychiatric comorbidity in patients with epilepsy. Searching for antiepileptic (anticonvulsant) and antidepressant-like medicines from natural products is very important for the treatment of this disease. The flower of Abelmoschus manihot (Linn.) Medicus has been reported to have neuroprotective effect against cerebral ischemia injury. In order to further explore the activity of Abelmoschus manihot on the central nervous system, the anticonvulsant and antidepressant-like effects of Abelmoschus manihot ethanol extract (AMEE) as well as its potential active components in vivo was investigated in the present study. It was found that AMEE could protect mice against PTZ-induced clonic convulsions and mortality. AMEE could also decrease immobility time in the FST in mice. Furthermore, the potential active components of AMEE in rat brain were identified by ultra performance liquid chromatography-mass spectrometer (UPLC-MS). Five parent components including isoquercitrin, hyperoside, hibifolin, quercetin-3'-O-glucoside, quercetin and three metabolites were detected in rat brain after administration of AMEE. In conclusion, eight flavonoids were identified in rat brain after administration of AMEE; meanwhile, these flavonoids might represent the potential bioactive components of AMEE and contribute to its anticonvulsant and antidepressant-like activity in vivo. PMID:21784623

Guo, Jianming; Xue, Caifu; Duan, Jin-ao; Qian, Dawei; Tang, Yuping; You, Yi

2011-07-23

126

Topological analysis of the brain stem of the frogs Rana esculenta and Rana catesbeiana.  

PubMed

The ventricular sulcal pattern and the cytoarchitectonic organization of the brain stem of the frogs Rana esculenta and Rana catesbeiana have been studied in transversely cut, Nissl stained serial sections. Four longitudinal sulci, the sulcus medianus inferior, the sulcus intermedius ventralis, the sulcus limitans and the sulcus medianus superior could be distinguished in both species. A fifth longitudinal groove, the sulcus intermedius dorsalis, was found only in Rana esculenta. With the aid of the usual cytoarchitectonic criteria 25 cell masses have been delineated in Rana esculenta and 27 in Rana catesbeiana. These cell masses can be distributed over the following categories (numbers added in brackets for Rana catesbeiana, if different from those in Rana esculenta): primary efferent or motor, 8; primary afferent or sensory, 4(6); "relay" centers, 7. Contrary to statements in the literature the reticular formation can be divided into six separate cell groups. The majority of the nuclei form part of the central gray, which constitutes a rather wide zone in anurans; three reticular nuclei lie partly within the stratum griseum and partly within the stratum album; six nuclei are entirely embedded in the stratum album. The morphological pattern of the cell masses and their relationship to the ventricular sulci were studied with the aid of a graphical reconstruction procedure termed topological analysis (cf. Nieuwenhuys, '74 and figs. 15, 16). This analysis yielded the following results: The sulcus limitans extends throughout the rhombencephalon, dividing this brain part into a basal plate and an alar plate. The cell masses in the basal plate fit into two longitudinal zones, a medial area ventralis and a lateral area intermedioventralis. The area ventralis contains three somatic motor nuclei (IV, VI and XII) and the rhombencephalic medial reticular zone. The latter may be primarily considered as a somatic motor coordinating center. The area intermedioventralis contains the visceral motor nuclei of V, VII, IX and X. However, the basal plate also contains a number of non-motor centers, for example the superior olive. The alar plate contains visceral sensory, general somatic sensory and special somatic sensory centers. Two cell masses, the nucleusfasciculi solitarii and the nucleus visceralis secundarius, represent together a discontinuous visceral sensory zone. Both of these nuclei are situated immediately dorsal to the sulcus limitans. The special somatic sensory area, i.e., the area of termination of the eighth nerve, occupies a considerable part of the alar plate. This area comprises, apart from a large zone of diffuse gray, three distinct cell masses... PMID:1083857

Opdam, R; Kemali, M; Nieuwenhuys, R

1976-02-01

127

Cytological changes in the pars distalis of pituitary of the green frog, Rana esculenta L., during the reproductive cycle  

Microsoft Academic Search

The cytological changes in the pars distalis of pituitary of male and female green frog, Rana esculenta during the reproductive cycle have been studied by examining the form, cytoplasmic granulation and numerical proportions of the different cell types. Some sex differences were recorded, particularly in relative total number of cells in a median sagittal section of the pars distalis. No

Rakesh K. Rastogi; G. Chieffi

1970-01-01

128

The function of fat bodies in relation to the hypothalamo-hypophyseal-gonadal axis in the frog, Rana esculenta  

Microsoft Academic Search

In this study the authors have tried to furnish experimental support for the importance of fat bodies in the normal functioning of the hypothalamo-hypophyseal-gonadal system of the male frog, Rana esculenta. These experiments have shown a hypothalamohypophyseal control of the mobilization of fat body contents, directly involved in the control of testicular activity. Furthermore it is proposed that the fat

G. Chieffi; R. K. Rastogi; L. Iela; M. Milone

1975-01-01

129

Nature of taro ( Colocasia esculenta (L.) Schott) genetic diversity prevalent in a Pacific Ocean island, Vanua Lava, Vanuatu  

Microsoft Academic Search

Taro (Colocasia esculenta (L.) Schott), cultivated in Vtuboso, a village of northern Vanuatu, Melanesia, was surveyed to: (1) assess the extent of morphological and molecular variation being maintained by growers at the village level and, (2) compare this diversity with the diversity found in the crops in Vanuatu. Ethnobotanical data were combined with AFLP analysis to elucidate possible sources of

S. Caillon; J. Quero-Garcia; J.-P. Lescure; V. Lebot

2006-01-01

130

Acetylcholinesterase-containing nerve cells in the pineal complex and subcommissural area of the frogs, Rana ridibunda and Rana esculenta  

Microsoft Academic Search

In Rana esculenta and Rana ridibunda the frontal organ and the pineal organ (epiphysis cerebri) form a pineal complex. Approximately 60 nerve cells of the frontal organ and 220–320 nerve cells of the pineal organ display a positive acetylcholinesterase reaction (Karnovsky and Roots, 1964). The dorsal wall of the pineal organ is considerably richer in acetylcholinesterase-positive neurons than the ventral

Kenjiro Wake; Manfred Ueck; Andreas Oksche

1974-01-01

131

Direct microtuber formation and enhanced growth in the acclimatization of in vitro plantlets of taro ( Colocasia esculenta spp.) using hydroponics  

Microsoft Academic Search

This paper describes an effective procedure for the acclimatization of in vitro produced plantlets of taro (Colocasia esculenta spp.) in a hydroponic system. In vitro taro plantlets, 5cm in height, were derived from mass propagation by shoot tip culture on MS medium. Plantlets with well-developed roots were used for the experiments. Comparisons of growth were made for in vitro taro

Duong Tan Nhut; Nguyen Thi Dieu Huong; Dinh Van Khiem

2004-01-01

132

Effects of temperature fluctuations on cuttlebone formation of cuttlefish Sepia esculenta  

NASA Astrophysics Data System (ADS)

The morphological characteristics and the cuttlebone formation of Sepia esculenta exposed to different water temperature fluctuations were investigated under laboratory conditions. Temperature fluctuation cycles (15 cycles, 60 d in total) consisted of the following three regimes of 4 d duration: keeping water temperature in 26°C for 3 d (Group A), 2 d (Group B), 0 d (Group C, control); then keeping water temperature in 16°C for the next 1, 2, 4 d. No significant difference in the survival rate was observed between the control and temperature fluctuation groups ( P >0.05). Lamellar depositions in a temperature fluctuation cycle were 2.45±0.02 for Group A, 2.00±0.02 for Group B, and 1.78±0.02 for Group C ( P< 0.05). The relationship between age and number of lamellas in the cuttlebone of S. esculenta under each water temperature fluctuation could be described as the linear model and the number of lamellas in the cuttlebone did not correspond to actual age. Group A had the highest cuttlebone growth index (CGI), the lowest locular index (LI), and inter-streak distances comparing with those of control group. However, the number of lamellas and LI or CGI showed a quadratic relationship for each temperature fluctuation group. In addition, temperature fluctuations caused the breakage of cuttlebone dark rings, which was considered a thermal mark. The position of the breakage in the dark rings was random. This thermal mark can be used as supplementary information for marking and releasing techniques.

Lei, Shuhan; Zhang, Xiumei; Liu, Songlin; Chen, Siqing

2012-07-01

133

Characterization of a saccharide-binding protein from Talisia esculenta seeds with trypsin inhibitory activity.  

PubMed

Some proteins exhibit characteristics that suggest they have a primary, if not an exclusive role in nutrient reserve storage. The best studied examples are the storage proteins that accumulate specifically in developing seeds. Some of these protein demonstrate biological activities that could contribute to resistance to pest, pathogens or abiotic stresses. In this study we present the biochemical characterization and cloning of the major protein from seeds of T. esculenta (Talisin), a member of the Sapindaceae family. The N-terminal sequence of the protein isolated was used to produce a degenerated primer. This primer allowed the amplification of the Talisin cDNA by RTPCR from mRNA of the T. esculenta seeds protein. The sequence analysis of the cloned cDNA, demonstrated a 756 bp sequence encoding a peptide of 198 amino acids. The deduced peptide presented high similarity to a typical VSP, the 22-kDa protein in lychee (73 %) and 50.0 % identity to Theobroma bicolor reserve protein. Identities of 52.0 % and 44.0 % to trypsin inhibitors from Treobroma mammosum and Populus tremula respectively. In conclusion, we may suggest that Talisin could be a seed storage protein with affinity properties, i.e. interacts with carbohydrates and trypsin enzyme. PMID:20001918

Freire, Maria das Graças M; Vasconcelos, Ilka Maria; Oliveira, Marcos Vinïcius; Filho, Gonçalo Apolinário de Souza; Macedo, Maria Lïgia R

2009-01-01

134

Cassava tissue culture and long-term preservation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cassava (Manihot esculenta Crantz) is cultivated mainly for its starchy roots as an important staple food for the tropics. M. esculenta is the only cultivated species in the genus Manihot, which contains 98 species, mostly native to Brazil. In recent years several research groups have reported metho...

135

Effect of including fresh Stylo (Stylosanthes guianensis, CIAT 184) and cassava foliage (Manihot esculenta, Crantz), fed separately or in a mixture on digestibility, intake, and N retention in growing pigs  

Microsoft Academic Search

Eight individually housed crossbred (Large White x Mong Cai) castrated male pigs of 26 to 30 kg were used to study the effect of fresh stylo (Stylosanthes guianensis, CIAT 184) (ST) and cassava foliage (CL), fed alone or in a mixture (MIX), together with a basal diet (Ctrl), on the intake, nutrient digestibility and nitrogen balance. The basal diet and

Bounlieng Khoutsavang; Bounthong Bouahom; Brian Ogle

136

Screening for in vitro metabolites of Abelmoschus manihot extract in intestinal bacteria by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry.  

PubMed

Abelmoschus manihot has drawn much attention recently due to its potential beneficial health effects after oral administration. However, the metabolic fate of A. manihot in intestinal flora is not well understood. In this paper, we describe a strategy using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS) with automated data analysis software (MetaboLynx™) for fast analysis of the metabolic profile of flavonoids from A. manihot in intestinal flora. The human and rat incubated samples collected 72 h in the anaerobic incubator were analyzed by UPLC-Q-TOF MS within 10 min. A total of 14 metabolites were identified in human and rat incubated solution compared with blank samples. The results indicated that hydrolysis, hydroxylation and acetylation were the major metabolic pathways of flavonoids in A. manihot extract in vitro. MS(E) was used for simultaneous acquisition of precursor ion information and fragment ion data at high and low collision energy in one analytical run, which facilitated the fast structural characterization of metabolites. This work demonstrated the potential of the UPLC-Q-TOF MS approach using Metabolynx for fast and automated identification of metabolites of natural product in intestinal flora. PMID:22119023

Xue, Caifu; Jiang, Shu; Guo, Jianming; Qian, Dawei; Duan, Jin-ao; Shang, Erxin

2011-11-07

137

Inhibition of human lanosterol synthase by the constituents of Colocasia esculenta (taro).  

PubMed

Ethanol extracts of lyophilized vegetables were tested for inhibition of human lanosterol synthase (hOSC) in order to find the compounds to suppress cholesterol biosynthesis. Of 130 samples tested, twelve samples showed significant inhibition. Among them, Colocasia esculenta (taro) showed the highest inhibition (55% inhibition at 300 microg/ml). Examination of activity variation among eight taro cultivars indicated that "Aichi-wase" and "Yatsugashira" had the most potent activity for hOSC inhibition. In order to identify the active constituent of taro, ethanol extracts of "Aichi-wase" were partitioned with hexane and aqueous methanol, and fractionated by silica gel column chromatography. Inhibitory activity was concentrated in two major active fractions. Further purification of these fractions by preparative HPLC gave three monogalactosyldiacylglycerols and five digalactosyldiacylglycerols as active compounds that showed 28 to 67% inhibitory activities at the concentration 300 microg/ml. PMID:15684488

Sakano, Yuichi; Mutsuga, Motoh; Tanaka, Rie; Suganuma, Hiroyuki; Inakuma, Takahiro; Toyoda, Masatake; Goda, Yukihiro; Shibuya, Masaaki; Ebizuka, Yutaka

2005-02-01

138

The amino acid sequence of cytochrome f from the brown alga Alaria esculenta (L.) Grev.  

PubMed

Cytochrome f was isolated from the brown alga Alaria esculenta and the amino acid sequence was determined. The native haemoprotein has a molecular weight of 9800 and consists of a single polypeptide chain of 86 amino acid residues with a haem group bonded to cysteine residues at positions 14 and 17. The N-terminus is not acetylated and no methylated lysines were found. Sequences of three other algal cytochromes f were compared with that of Alaria and 22 out of 92 positions were common to the four sequences. One-half of these conserved sites occur between positions 49 and 63. Detailed evidence for the amino acid sequence of Alaria cytochrome has been deposited as Supplementary Publication SUP 50048 (6 pages) at the British Library (Lending Division), Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1975) 145, 5. PMID:1191259

Laycock, M V

1975-07-01

139

The amino acid sequence of cytochrome f from the brown alga Alaria esculenta (L.) Grev.  

PubMed Central

Cytochrome f was isolated from the brown alga Alaria esculenta and the amino acid sequence was determined. The native haemoprotein has a molecular weight of 9800 and consists of a single polypeptide chain of 86 amino acid residues with a haem group bonded to cysteine residues at positions 14 and 17. The N-terminus is not acetylated and no methylated lysines were found. Sequences of three other algal cytochromes f were compared with that of Alaria and 22 out of 92 positions were common to the four sequences. One-half of these conserved sites occur between positions 49 and 63. Detailed evidence for the amino acid sequence of Alaria cytochrome has been deposited as Supplementary Publication SUP 50048 (6 pages) at the British Library (Lending Division), Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1975) 145, 5.

Laycock, M V

1975-01-01

140

Talisia esculenta lectin and larval development of Callosobruchus maculatus and Zabrotes subfasciatus (Coleoptera: Bruchidae).  

PubMed

Bruchid larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil and the Mexican bean weevil, are pests that damage stored seeds. Plant lectins have been implicated as antibiosis factors against insects, particularly the cowpea weevil, Callosobruchus maculatus. Talisia esculenta lectin (TEL) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae. TEL produced ca. 90% mortality to these bruchids when incorporated in an artificial diet at a level of 2% (w/w). The LD(50) and ED(50) for TEL was ca. 1% (w/w) for both insects. TEL was not digested by midgut preparations of C. maculatus and Z. subfasciatus. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. PMID:12049788

Macedo, Maria Ligia R; das Graças Machado Freire, Maria; Novello, José Camillo; Marangoni, Sérgio

2002-06-01

141

Mechanisms of the insecticidal action of TEL (Talisia esculenta lectin) against Callosobruchus maculatus (Coleoptera: Bruchidae).  

PubMed

Plant lectins have insecticidal activity that is probably mediated through their ability to bind carbohydrates. To examine the influence of sugars on the insecticidal activity of a lectin from Talisia esculenta seeds (TEL), the lectin was mixed with mannose, glucose, or mannose plus glucose. Mannose abolished the insecticidal activity. Affinity chromatography showed that TEL bound to midgut proteins of the insect Callosobruchus maculatus. Immunoblotting showed that TEL recognized some proteins, probably glycoproteins, present in the midgut membrane of this insect. The principal proteases responsible for digestive proteolysis in fourth instar larvae of C. maculatus were purified by chromatography on activated thiol-Sepharose. These purified proteases were unable to digest TEL after a 15-h incubation. These results suggest that the insecticidal activity of TEL involves a specific carbohydrate-lectin interaction with glycoconjugates on the surface of digestive tract epithelial cells, as well as binding to assimilatory glycoproteins present in midgut extracts and resistance to enzymatic digestion by cysteine proteinases. PMID:15146543

Macedo, Maria Lígia Rodrigues; de Castro, Márcia Mota; Freire, Maria das Graças Machado

2004-06-01

142

Organization of atrial natriuretic factor-like immunoreactive system in the brain of the frog Rana esculenta during development  

Microsoft Academic Search

Immunocytochemical distribution of the atrial natriuretic factor (ANF) has been studied in the brain and pituitary of the\\u000a anuran Rana esculenta during development and in juvenile animals. Using human ANF and rat ?-ANF antisera, immunoreactive cell bodies and nerve\\u000a fibers were revealed in stage II–III tadpoles and in successive larval stages. Soon after hatching, stages II–III, the ANF-like-immunoreactive\\u000a elements were

Mauro Vallarino; Maura Mathieu; Claudia Pinelli; Rakesh K. Rastogi

1998-01-01

143

Caffeine-evoked contractures in single slow (tonic) muscle fibres of the frog ( Rana temporaria and R. esculenta )  

Microsoft Academic Search

Single slow (tonic) muscle fibres were dissected from cruralis muscles of Rana temporaria and R. esculenta. Increasing concentrations of caffeine were applied in Ringer solution, and contractures were measured isometrically. Sigmoid\\u000a caffeine concentration-response curves were obtained, the threshold value being near 1.2mmol\\/l, and maximum contractures being\\u000a obtained with 10 to 20 mmol\\/1 concentrations of caffeine. Contracture solutions were modified by

C. Hoock; J. Steinmetz; H. Schmidt

1996-01-01

144

Dry matter, nutrient composition and palatability\\/acridity of eight exotic cultivars of cocoyams–taro ( Colocassia esculenta ) in Samoa  

Microsoft Academic Search

Dry matter (DM) content, nutrient composition and palatability\\/acridity test on eight exotic cocoyams–taro (Colocassia esculenta) cultivars in Samoa were carried out. The exotic taro cultivars investigated were Pwetepweta and Palau 3a (Saliemoa), Pwetepwetb, Pastora and Palau 1, 3b 10, and 20 (Safaatoa). These taro cultivars were obtained from two farms (Saliemoa and Safaatoa) in Samoa and similar cultivars from the

E. M. Aregheore; D. Perera

2003-01-01

145

The edible brown seaweed Alaria esculenta (Phaeophyceae, Laminariales): hybridization, growth and genetic comparisons of six Irish populations  

Microsoft Academic Search

Alaria esculenta populations from six differentgeographical locations on the Irish coast wereexamined for hybridization abilities, growth rates andgenetic make-up with a view towards identifying afast-growing strain suitable for aquaculture.Hybridization experiments under laboratory conditionswith the three most geographically dispersedpopulations showed that all cross combinations wereinterfertile, although differences were found insurvival, and in blade and hapteron morphology. Acomparison of relative growth rates

Stefan Kraan; Adriana Verges Tramullas; Michael D. Guiry

2000-01-01

146

Physicochemical, thermal properties and microstructure of six varieties of taro ( Colocasia esculenta L. Schott) flours and starches  

Microsoft Academic Search

Taro (Colocasia esculenta L. Schott) flours were prepared from six varieties of taro corms coded as RIN, RIE, CN, CE, KW1 and KW2. Starch yields prepared from the flours varied between 66.5% for KW2 to 86.6% for RIE. The proteins content varied from 2.9% for KW1 to 4.9% for CN in the flours. Taro starch had irregular, polygonal shapes and

Aboubakar; Y. N. Njintang; J. Scher; C. M. F. Mbofung

2008-01-01

147

Distribution of gonadotropin-releasing hormone-like peptides in the brain during development of juvenile male Rana esculenta  

Microsoft Academic Search

The distribution and density of cell bodies and fibers immunoreactive to GnRH-like peptides were investigated in the brain of male juvenile frogs (Rana esculenta) during postmetamorphic development. An immunohistochemical technique was used, involving antisera raised against 4 variants of GnRH: mammalian GnRH, chicken GnRH-I, chicken GnRH-II and salmon GnRH. A comparison of the immunohistochemical distribution at 8 different developmental stages

B. D'Aniello; M. Masucci; M. di Meglio; G. Ciarcia; R. K. Rastogi

1991-01-01

148

Protective effect of total flavones of Abelmoschus manihot L. Medic against poststroke depression injury in mice and its action mechanism.  

PubMed

Total flavones of Abelmoschus manihot L. Medic (TFA) is the major active component isolated from the traditional Chinese herb Abelmoschus manihot L. Medic. We investigated the protective effect of TFA against poststroke depression (PSD) injury in mice and its action mechanism. A mouse model of PSD was induced by middle cerebral artery occlusion (MACO) 30 min/reperfusion, followed by isolation feeding and chronic unpredictable mild stress for 2 weeks. Treatment groups received TFA at three different doses (160, 80, and 40 mg/kg, p.o.) or fluoxetine (Flu, 2.5 mg/kg, p.o.) daily for 24 days. Change in behavior, brain tissue malondialdehyde (MDA) levels, and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured. The expression of brain-derived neurotrophic factor (BDNF) was detected by immunohistochemistry, and mRNA expression of BDNF and cAMP response element-binding protein (CREB) analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Treatment with TFA (160, 80, and 40 mg/kg) significantly ameliorated mice escape-directed behavioral impairment induced by PSD, markedly reduced MDA levels, and increased the activity of SOD, GSH-Px close to normal levels. TFA administration also attenuated PSD-induced neuronal death/losses, upregulated expression of BDNF both at mRNA and protein levels, as well as CREB mRNA levels. TFA had a protective effect against PSD injury in mice. Cardioprotection involves the inhibition of lipid peroxidation and upregulation of BDNF-CREB levels in the hippocampus, which may also be important mechanism of its antidepressants. This potential protection makes TFA a promising therapeutic agent for the PSD. PMID:19248161

Liu, Mei; Jiang, Qiu-Hong; Hao, Ji-Li; Zhou, Lan-Lan

2009-03-01

149

A voltage-dependent and pH-sensitive proton current in Rana esculenta oocytes.  

PubMed

Voltage clamp technique was used to study macroscopic ionic currents in Rana esculenta oocytes. Depolarization steps led to the activation of a single type of outward current (Iout) when contaminant potassium and calcium-dependent chloride currents were pharmacologically inhibited. The voltage threshold of Iout activation was 10 mV and this current, which did not inactivate, presented a deactivation the time constant of 73 +/- 21 msec (n = 26) corresponding to a membrane voltage of -60 mV. Its reversal potential (Erev) was dependent on the magnitude of the depolarization and also on pulse duration. These changes in Erev were thought to reflect intracellular ion depletion occurring during activation of the remaining outward current. Furthermore, the activation threshold of Iout was clearly affected by modifications in extracellular and intracellular H+ concentrations. Indeed, intracellular alkalinization (evoked by external application of ammonium chloride) or extracellular acidification induced a rightward shift in the activation threshold while intracellular acidification (evoked by external application of sodium acetate) or extracellular alkalinization shifted this threshold toward a more negative value. Lastly, Iout was dramatically reduced by divalent cations such as Cd2+, Ni2+ or Zn2+ and was strongly decreased by 4 Aminopyridine (4-AP), well-known H+ current antagonists already described in many cell types. Therefore, it was suggested that the outward current was prominently carried by H+ ions, which may play a key role in the regulation of intracellular pH and subsequent pH dependent processes in Rana oocyte. PMID:8568856

Humez, S; Fournier, F; Guilbault, P

1995-09-01

150

Binding effectiveness of Colocassia esculenta gum in poorly compressible drugs-paracetamol and metronidazole tablet formulations.  

PubMed

The effectiveness of a polysaccharide gum obtained from the cormels of Colocassia esculenta was evaluated comparatively with acacia and methylcellulose as binders in the formulation of poorly compressible drugs. The granules of these drugs produced by wet massing method using colocassia and acacia gums as binders have high compressibility index indicating poor flow. Based on this parameter, the granules produced with methylcellulose as binder seem to flow better. The properties of tablets evaluated include breaking strength, friability, disintegration time and dissolution rate. The new polysaccharide gum showed better concentration-strength profile than acacia while methylcellulose yielded mechanically more stable tablets than the two binders. The resistance of tablets to abrasion was poor in metronidazole tablets formulated with colocassia gum. The in vitro availability characteristics showed that tablets produced with the new gum show acceptable disintegration time and release profile within a certain range of its concentration in tablets. At 4% w/w nominal concentration of colocassia gum in metronidazole tablets and 6% w/w in paracetamol, tablets show very long disintegration time and prolonged release profile. The binders used for comparison yielded tablets that show better in vitro release characteristics. PMID:10920535

Chukwu, K I; Udeala, O K

151

Response of renal parenchyma and interstitium of Rana snk. esculenta to environmental pollution.  

PubMed

The mesonephroi of two groups of Rana esculenta collected from two rice fields near Pavia, one relatively unpolluted and one polluted, were morphologically and histochemically investigated. Light and electron microscopy analyses were performed and certain enzyme activities studied (succinic dehydrogenase, SDH, alkaline phosphatase, AlkPase, acid phosphatase, AcPase, catalase, CAT, and NOS-related nicotinamide adenine dinucleotide phosphatase, NOS/NADPHd). The expression of the inducible NOS (iNOS) was evaluated through immunohistochemistry. In the renal parenchyma of the polluted group some structural modifications, mainly in the glomeruli and the proximal tubule epithelium, were observed. Peritubular inflammatory foci in most polluted samples were often found to be in combination with parasitic cysts. However, no necrotic processes were found in the renal parenchyma. Compared to controls, the histochemical studies on contaminated frogs evidenced an increase of the AcPase, NOS and CAT activities, and of the iNOS immunoexpression as well. All the results showed a good correspondence between the biomarkers responses and the environmental stress conditions. Overall, we can state that studying the sub-lethal effects of contamination in amphibians naturally exposed to toxicants has shown to be significant for the assessment of site-specific risk and potential hazards behind the phenomenon of progressive amphibian decline. PMID:21497903

Fenoglio, C; Albicini, F; Milanesi, G; Barni, S

2011-04-16

152

Cyclosporin A stimulates Na+ transport across the isolated skin of Rana esculenta.  

PubMed

Cyclosporin A (Cs A), added to the fluid bathing the internal surface of the isolated skin of Rana esculenta, increased short-circuit current (SCC) with a maximal effect at 5 microM. This effect was completely inhibited by amiloride (0.2 mM in the fluid bathing the external surface). By measuring both transepithelial fluxes of 22Na+ across symmetrical parts of the short circuited skin, Cs A was found to increase the net absorption of Na+. Naproxen (10 microM), a cyclooxygenase inhibitor, decreased the stimulation by Cs A of SCC, suggesting that in this stimulation prostaglandins are involved. The Cs A effect on Na+ transport could be caused by an inhibition of a Ca2+/calmodulin-dependent protein phosphatase, i.e. calcineurin, since: a) it is mimicked by another inhibitor of calcineurin, i.e. fenvalerate: b) the action of Cs A and fenvalerate on SCC are decreased by the calmodulin inhibitor W7. PMID:9587652

Lippe, C; Bellantuono, V; Quaranta, A; Castronuovo, G; Cassano, G; Ardizzone, C

1997-10-01

153

Effect of calcitonin gene-related peptide on sodium absorption through isolated skin of Rana esculenta.  

PubMed

Calcitonin gene-related peptide (CGRP) added to the internal fluid bathing the isolated skin of Rana esculenta strongly stimulates the active sodium absorption. This action is dose-dependent, the dose eliciting the maximal effect being 2 . 10(-7) M; alpha and beta CGRP exhibit the same potency. The CGRP action on sodium transport is mainly due to its interaction with CGRP1 receptors, since it is inhibited by CGRP8-37, its specific antagonist. The second messengers probably involved in the action of CGRP are cAMP and Ca+2, since this action is reduced by SQ22536 and W7, which are inhibitors of adenyl cyclase and calmodulin respectively. On the contrary, inhibitors of protein kinase C (1-O-hexadecyl-2-O-methyl-sn-glycerol) and nitric oxide synthase (L-NAME) do not modify the action on sodium transport. ETYA, an inhibitor of all the metabolic pathways of arachidonic acid, decreases the CGRP action by 38%. In order to search for the arachidonic acid metabolites involved in the CGRP action, the effect of the following inhibitors was tested: aspirin and naproxen (for cyclooxygenases), NDGA (for cyclooxygenases), NDGA (for lipoxygenases) clotrimazole (for epoxygenases). None of these substances is able to inhibit the CGRP action on sodium transport. Moreover, adding arachidonic acid inhibits the CGRP action, but this effect was also obtained by another unsaturated fatty acid, oleic acid. Since unsaturated fatty acids are able to inhibit the protein kinase A, these results indirectly support the role of cAMP as a second messenger of the CGRP action on sodium transport. PMID:8818196

Castronuovo, G; Lippe, C; Bellantuono, V; Calzaretti, G; Ardizzone, C

1996-01-01

154

DNA polymorphism in morels: complete sequences of the internal transcribed spacer of genes coding for rRNA in Morchella esculenta (yellow morel) and Morchella conica (black morel).  

PubMed Central

The internal transcribed spacer (ITS) of the gene coding for rRNA was sequenced in both directions with the gene walking technique in a black morel (Morchella conica) and a yellow morel (M. esculenta) to elucidate the ITS length discrepancy between the two species groups (750-bp ITS in black morels and 1,150-bp ITS in yellow morels.

Wipf, D; Munch, J C; Botton, B; Buscot, F

1996-01-01

155

Variation in fertilisation abilities between hemiclonal hybrid and sexual parental males of sympatric water frogs ( Rana lessonae , R. esculenta , R. ridibunda )  

Microsoft Academic Search

In many species, males and females mate with multiple partners, which gives rise to sperm competition and multiple paternity. The experiments on water frogs presented here demonstrate that such sperm competition can affect the structure and dynamics of mixed-species communities. The hybrid frog Rana esculenta ( LR) mates with one of its parental species, usually R. lessonae ( LL), although

Heinz-Ulrich Reyer; Bettina Niederer; Attila Hettyey

2003-01-01

156

Assessment of Antioxidant Properties in Fruits of Myrica esculenta: A Popular Wild Edible Species in Indian Himalayan Region  

PubMed Central

Crude extract of Myrica esculenta fruits, a wild edible species of Indian Himalayan Region, was evaluated for phenolic compounds and antioxidant properties. Results revealed significant variation in total phenolic and flavonoid contents across populations. Among populations, total phenolic content varied between 1.78 and 2.51?mg gallic acid equivalent/g fresh weight (fw) of fruits and total flavonoids ranged between 1.31 and 1.59?mg quercetin equivalent/g fw. Antioxidant activity determined by 2,2?-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging, 1,1-diphenyl-2-picrylhydrazyl radical scavenging and ferric reducing antioxidant power (FRAP) exhibited considerable antioxidant potential and showed significant positive correlation with total phenolic and total flavonoids content. High performance liquid chromatography analysis revealed significant variation (P esculenta fruits while providing relished taste would also help in reduction of free radicals. Therefore, this wild edible species deserves promotion in the region through horticulture and forestry interventions.

Rawat, Sandeep; Jugran, Arun; Giri, Lalit; Bhatt, Indra D.; Rawal, Ranbeer S.

2011-01-01

157

Inhibitory effects of flavonoids from Abelmoschus manihot flowers on triglyceride accumulation in 3T3-L1 adipocytes.  

PubMed

The 95% EtOH extract from the flowers of Abelmoschus manihot (L.) Medic showed inhibitory activity on TG accumulation in 3T3-L1 preadipocyte. Chemical studies on the active fraction led to the isolation of 14 flavonoids (1-14). To clarify the multi-mechanism of the isolates on preadipocyte differentiation, the levels of TG and FFA and the related role transcription factors (PPAR?, CEBP/?, and ap2) expression were evaluated. At the concentration of 30 ?M, compounds 1-6 and 10-14 showed inhibitory activity on TG accumulation significantly in mature 3T3-L1 cells. 1, 2, 4-7, 9, 10, 13, and 14 reduced the level of FFA. At the molecular level, the mRNA expressions of PPAR?, CEBP/?, and ap2 were down-regulated by compounds 1, 5, 9, 12, 13; 1-8, 10-14; and 1-4, 6, 8-12, 14, respectively. The structure-activity relationships of the 14 flavonoids were also discussed. PMID:21281705

An, Yating; Zhang, Yi; Li, Chunmei; Qian, Qian; He, Wei; Wang, Tao

2011-01-31

158

Inhibitory effect of total flavone of Abelmoschus manihot L. Medic on NMDA receptor-mediated current in cultured rat hippocampal neurons.  

PubMed

The modulatory effect of Total Flavone of Abelmoschus manihot L. Medic (TFA) on NMDA-activated current (I(NMDA)) was investigated in cultured rat hippocampal neurons using the whole-cell patch-clamp technique. TFA rapidly and reversibly inhibited the I(NMDA) in a concentration-dependent manner. Furthermore, TFA non-competitively inhibited the I(NMDA) by enhancement of the NMDA receptor desensitization. In addition, intracellular application of TFA did not alter the TFA inhibition of I(NMDA). These results suggest that the inhibition of the NMDA receptor response by TFA could be one of the mechanisms for TFA-mediated neuroprotective actions. PMID:16616791

Cheng, Xin-Ping; Qin, Song; Dong, Liu-Yi; Zhou, Jiang-Ning

2006-04-17

159

Fast and automated characterization of major constituents in rat biofluid after oral administration of Abelmoschus manihot extract using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry and MetaboLynx.  

PubMed

In drug metabolism research, the setting up of a complex series of mass spectrometry experiments and the subsequent analysis of the large amounts of data produced are often time-consuming. In this paper, we describe a strategy using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/QTOFMS) with automated data analysis software (MetaboLynx) for fast analysis of the metabolic profile of flavonoids in Abelmoschus manihot. Rat plasma and urine samples collected 1 h and 0-12 h after oral administration of Abelmoschus manihot were analyzed by UPLC/QTOFMS within 15 min. The post-acquisition data were processed using MetaboLynx. With key parameters carefully set, MetaboLynx is able to show the presence of a wide range of metabolites with only a limited requirement for manual intervention and data interpretation time. A total of 16 and 38 metabolites were identified in plasma and urine compared with blank samples. The results indicated that methylation and glucuronidation after deglycosylation were the major metabolic pathways of flavonoid glycosides in Abelmoschus manihot. The present study provided important information about the metabolism of flavonoid glycosides in Abelmoschus manihot which will be helpful for fully understanding the mechanism of action of this herb. Furthermore, this work demonstrated the potential of the UPLC/QTOFMS approach using MetaboLynx for fast and automated identification of metabolites from Chinese herbal medicines. PMID:20069688

Guo, Jianming; Shang, Er-Xin; Duan, Jin-Ao; Tang, Yuping; Qian, Dawei; Su, Shulan

2010-02-01

160

Role of pCeMT, a putative metallothionein from Colocasia esculenta, in response to metal stress.  

PubMed

Metallothioneins (MTs) play a major role in metal homeostasis and/or detoxification in plants. In this study, a novel gene, pCeMT, was isolated from Colocasia esculenta and characterized. Our results indicate that Escherichia coli cells expressing pCeMT exhibited enhanced Cd, Cu, and Zn tolerance and accumulation compared with control cells. Furthermore, pCeMT-overexpressing tobacco seedlings displayed better growth under Cd, Cu, and Zn stresses and accumulated more Cd and Zn compared with the wild type. Interestingly, transgenic tobacco displayed markedly decreased hydrogen peroxide (H(2)O(2)) and lipid peroxidation levels under Cd, Cu, and Zn treatments. These results suggest that pCeMT could play an important role in the protection of plant cells from oxidative stress by reactive oxygen species (ROS) scavenging and in the detoxification of free metals by metal binding, leading to improved plant metal tolerance. PMID:23344478

Kim, Yeon-Ok; Jung, Sera; Kim, Kyounghyoun; Bae, Hyeun-Jong

2013-01-03

161

Effect of cooking on the proximate composition of seven accessions of Colocasia esculenta (L.) Schott tubers growing in South Africa.  

PubMed

Colocasia esculenta (L.) Schott (cocoyam) is cultivated mainly for its edible tubers. The effect of cooking the tubers on the proximate composition of seven accessions (UFCe1-UFCe7) of the crop growing in South Africa was investigated. When compared with the uncooked, the ash and crude fibre contents of the accessions significantly decreased after cooking. The moisture content, crude protein, crude lipid, carbohydrate and caloric contents increased with cooking in all the accessions, except UFCe1 and UFCe5 where the crude lipid content reduced. The results indicate that cooking enhanced the carbohydrate, energy and protein contents of the tubers. They further showed that the tubers could be used for allergic infants, old people and invalids since the fibre contents were still appreciably high despite the slight reduction after cooking the tubers. PMID:19468953

Lewu, Muinat N; Adebola, Patrick O; Afolayan, Anthony J

2009-01-01

162

A Novel Glycosylphosphatidylinositol-Anchored Glycoside Hydrolase from Ustilago esculenta Functions in ?-1,3-Glucan Degradation  

PubMed Central

A glycoside hydrolase responsible for laminarin degradation was partially purified to homogeneity from a Ustilago esculenta culture filtrate by weak-cation-exchange, strong-cation-exchange, and size-exclusion chromatography. Three proteins in enzymatically active fractions were digested with chymotrypsin followed by liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis, resulting in the identification of three peptide sequences that shared significant similarity to a putative ?-1,3-glucanase, a member of glucoside hydrolase family 16 (GH16) from Sporisorium reilianum SRZ2. A gene encoding a laminarin-degrading enzyme from U. esculenta, lam16A, was isolated by PCR using degenerate primers designed based on the S. reilianum SRZ2 ?-1,3-glucanase gene. Lam16A possesses a GH16 catalytic domain with an N-terminal signal peptide and a C-terminal glycosylphosphatidylinositol (GPI) anchor peptide. Recombinant Lam16A fused to an N-terminal FLAG peptide (Lam16A-FLAG) overexpressed in Aspergillus oryzae exhibited hydrolytic activity toward ?-1,3-glucan specifically and was localized both in the extracellular and in the membrane fractions but not in the cell wall fraction. Lam16A without a GPI anchor signal peptide was secreted extracellularly and was not detected in the membrane fraction. Membrane-anchored Lam16A-FLAG was released completely by treatment with phosphatidylinositol-specific phospholipase C. These results suggest that Lam16A is anchored in the plasma membrane in order to modify ?-1,3-glucan associated with the inner cell wall and that Lam16A is also used for the catabolism of ?-1,3-glucan after its release in the extracellular medium.

Nakajima, Masahiro; Yamashita, Tetsuro; Takahashi, Machiko; Nakano, Yuki

2012-01-01

163

A novel glycosylphosphatidylinositol-anchored glycoside hydrolase from Ustilago esculenta functions in ?-1,3-glucan degradation.  

PubMed

A glycoside hydrolase responsible for laminarin degradation was partially purified to homogeneity from a Ustilago esculenta culture filtrate by weak-cation-exchange, strong-cation-exchange, and size-exclusion chromatography. Three proteins in enzymatically active fractions were digested with chymotrypsin followed by liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis, resulting in the identification of three peptide sequences that shared significant similarity to a putative ?-1,3-glucanase, a member of glucoside hydrolase family 16 (GH16) from Sporisorium reilianum SRZ2. A gene encoding a laminarin-degrading enzyme from U. esculenta, lam16A, was isolated by PCR using degenerate primers designed based on the S. reilianum SRZ2 ?-1,3-glucanase gene. Lam16A possesses a GH16 catalytic domain with an N-terminal signal peptide and a C-terminal glycosylphosphatidylinositol (GPI) anchor peptide. Recombinant Lam16A fused to an N-terminal FLAG peptide (Lam16A-FLAG) overexpressed in Aspergillus oryzae exhibited hydrolytic activity toward ?-1,3-glucan specifically and was localized both in the extracellular and in the membrane fractions but not in the cell wall fraction. Lam16A without a GPI anchor signal peptide was secreted extracellularly and was not detected in the membrane fraction. Membrane-anchored Lam16A-FLAG was released completely by treatment with phosphatidylinositol-specific phospholipase C. These results suggest that Lam16A is anchored in the plasma membrane in order to modify ?-1,3-glucan associated with the inner cell wall and that Lam16A is also used for the catabolism of ?-1,3-glucan after its release in the extracellular medium. PMID:22685137

Nakajima, Masahiro; Yamashita, Tetsuro; Takahashi, Machiko; Nakano, Yuki; Takeda, Takumi

2012-06-08

164

Estradiol-induced mitogen-activated protein kinase (extracellular signal-regulated kinase 1 and 2) activity in the frog (Rana esculenta) testis  

Microsoft Academic Search

Several lines of evidence support a key role of estradiol- 17 (E2) in male fertility. We have used a non-mammalian vertebrate model, the frog Rana esculenta, to investigate the regulation of extracellular signal-regulated kinase 1 and 2 (ERK1\\/2) activity in the testis during the annual sexual cycle and to study whether E2 exerts a role in sperma- togenesis through the

P Chieffi; G L Colucci-D' Amato; S Staibano; R Franco; L. Califano; G. Salvatore

2000-01-01

165

Tillage and plastic mulch effects on soil properties and growth and yield of cocoyam ( Colocasia esculenta) on an ultisol in southeastern Nigeria  

Microsoft Academic Search

Protected cultivation, mainly represented by plastic-film mulching, has greatly improved crop production worldwide since the 1950s. However, despite its widespread use in tropical USA, Europe and China, its use in sub-Saharan Africa is not widespread. A field experiment was conducted using cocoyam (Colocasia esculenta L. Schott) to evaluate the effects of two tillage systems (tilled and no-till) and plastic-film mulch

M. A. N. Anikwe; C. N. Mbah; P. I. Ezeaku; V. N. Onyia

2007-01-01

166

Morphological and Molecular Characterization of Common Bean Landraces and Cultivars from the Caribbean  

Microsoft Academic Search

bean on its introduction from South America, include cassava (Manihot esculenta Crantz subsp. esculenta), Little information is available regarding the relationship of Carib- pineapple (Ananas comosus (L.) Merr.), and peanuts bean bean landraces with the Andean and Mesoamerican gene pools of common bean (Phaseolus vulgaris L.) While small-seeded Meso- (Arachis hypogaea L.) (Rouse, 1992). Historical refer- american black beans are

L. A. Durán; M. W. Blair; M. C. Giraldo; R. Macchiavelli; E. Prophete; J. C. Nin; J. S. Beaver

2005-01-01

167

Sex and reproductive status related brain content of mammalian and chicken-II GnRHs in Rana esculenta.  

PubMed

Mammalian and chicken-II forms of gonadotropin-releasing hormone (mGnRH and cGnRH-II, respectively) have been measured simultaneously in the brain, pituitary, and peripheral terminal nerves (nasal area tissue) of adult males and females of a representative amphibian, Rana esculenta, during the annual reproductive cycle. Whereas in the male, brain concentrations of both GnRH forms showed significant reproductive status-related fluctuations, in the female brain only cGnRH-II content showed significant changes. The highest GnRH levels were recorded just prior to breeding in both sexes. In the pituitary both GnRHs were present in all seasons. In the peripheral terminal nerves, instead, only mGnRH was detected in all seasons confirming our previous immunohistochemical data. In both sexes furthermore, the brain and pituitary mGnRH levels were consistently much higher than those of cGnRH-II and there were no sex-related differences in the brain and pituitary content of GnRHs. Seasonal changes in brain GnRH levels may correlate with plasma sex steroid levels reinforcing the postulate that sex steroids affect GnRH neuronal systems. PMID:15305569

Rastogi, R K; King, J A; Di Fiore, M M; D'Aniello, B; Pinelli, C

1997-07-01

168

Validated HPTLC method for quantitative determination of gallic acid in stem bark of Myrica esculenta Buch.-Ham. ex D. Don, myricaceae.  

PubMed

A simple, rapid, and precise HPTLC method was developed for quantitative estimation of gallic acid in stem bark of Myrica esculenta, family Myricaceae. Separation was performed on silica gel 60F254 HPTLC plates using toluene-ethyl acetate-formic acid-methanol (3 + 3 + 0.6 + 0.4, v/v/v/v) mobile phase for separation of the extracted components. The determination was carried out in the UV densitometric absorbance-reflection mode at 280 nm. The amount of gallic acid in free and combined form in the stem bark powder was found to be 0.276 and 0.541%, respectively, on a dry weight basis. The method was validated in terms of linearity, accuracy, precision, and specificity according to International Conference on Harmonization guidelines. Gallic acid response was found to be linear over a broad concentration range of 0.4-2.0 microg/band. LOD and LOQ were 0.103 and 0.312 microg/spot, respectively. The developed method is capable of quantifying amounts of gallic acid in stem bark powder of M. esculenta. PMID:21140652

Patel, Kalpana G; Patel, Vandana G; Patel, Kirti V; Gandhi, Tejal R

169

Utilization of chicken feather hydrolysate as a novel fermentation substrate for production of exopolysaccharide and mycelial biomass from edible mushroom Morchella esculenta.  

PubMed

This study was performed to investigate the usability of chicken feather hydrolysate (Chicken feather peptone (CFP)) as substrate for mycelial biomass and extracellular polysaccharides (EPS) production from edible mushroom Morchella esculenta. The ability of CFP to support biomass and EPS production in edible mushroom M. esculenta was compared to those of two commercial peptones (Tryptone peptone (TP) and Fish peptone (FP)). The maximum biomass (16.3 g/l) and EPS (4.8 g/l) concentrations were achieved with TP. Second, high biomass (15.9 g/l) and EPS (4.6 g/l) concentrations were obtained with CFP. Also, biomass and EPS concentrations in CFP medium were statistically near to those in the TP medium. CFP and TP resulted in not only uniform pellets with smaller size (5 mm) but also faster mycelial growth compared to FP. This study showed for the first time that CFP could be effectively used as a novel EPS production substrate. PMID:22136136

Taskin, Mesut; Ozkan, Behzat; Atici, Okkes; Aydogan, Mehmet Nuri

2011-12-05

170

Phlorotannin production and lipid oxidation as a potential protective function against high photosynthetically active and UV radiation in gametophytes of Alaria esculenta (Alariales, Phaeophyceae).  

PubMed

Radiation damage can inter alia result in lipid peroxidation of macroalgal cell membranes. To prevent photo-oxidation within the cells, photoprotective substances such as phlorotannins are synthesized. In the present study, changes in total fatty acids (FA), FA composition and intra/extracellular phlorotannin contents were determined by gas chromatography and the Folin-Ciocalteu method to investigate the photoprotective potential of phlorotannins to prevent lipid peroxidation. Alaria esculenta juveniles (Phaeophyceae) were exposed over 20 days to high/low photosynthetically active radiation (PAR) in combination with UV radiation (UVR) in the treatments: PAB (low/high PAR + UV-B + UV-A), PA (low/high PAR + UV-A) or low/high PAR only. While extracellular phlorotannins increased after 10 days, intracellular phlorotannins increased with exposure time and PA and decreased under PAB. Interactive effects of time:radiation wavebands, time:PAR dose as well as radiation wavebands:PAR dose were observed. Low FA contents were detected in the PA and PAB treatments; interactive effects were observed between time:high PAR and PAB:high PAR. Total FA contents were correlated to extra/intracellular phlorotannin contents. Our results suggest that phlorotannins might play a role in intra/extracellular protection by absorption and oxidation processes. Changes in FA content/composition upon UVR and high PAR might be considered as an adaptive mechanism of the A. esculenta juveniles subjected to variations in solar irradiance. PMID:21958385

Steinhoff, Franciska S; Graeve, Martin; Bartoszek, Krzysztof; Bischof, Kai; Wiencke, Christian

2011-11-03

171

Pretreatment with the total flavone glycosides of Flos Abelmoschus manihot and hyperoside prevents glomerular podocyte apoptosis in streptozotocin-induced diabetic nephropathy.  

PubMed

Diabetic nephropathy (DN) is an important diabetic complication, and podocyte apoptosis plays a critical role in the development of DN. In the present study, we examined the preventive effect of the total flavone glycosides of Flos Abelmoschus manihot (TFA) on urinary microalbumin and glomerular podocyte apoptosis in experimental DN rats. The preliminary oral administration of TFA (200 mg/kg/day) for 24 weeks significantly decreased the urinary microalbumin to creatinine ratio and 24-h urinary total protein in streptozotocin-induced DN rats. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay indicated glomerular cell apoptosis in DN rats was significantly improved by pretreatment with TFA. Furthermore, fluorescence-activated cell sorting and Hoechst 33342 staining suggested preincubation with hyperoside (50 and 200 ?g/mL), the major active constituent of TFA, could significantly mitigate cultured podocyte apoptosis induced by the advanced glycation end-products (AGEs). Western blot analysis showed that increased caspase-3 and caspase-8 expressions induced by AGEs were also inhibited by pretreatment with hyperoside at both doses. Our results demonstrate that TFA pretreatment can decrease urinary albumin excretion in early-stage DN, which might be accomplished by preventing renal damage and podocyte apoptosis. PMID:22439874

Zhou, Lei; An, Xiao-Fei; Teng, Shi-Chao; Liu, Jing-Shun; Shang, Wen-Bin; Zhang, Ai-Hua; Yuan, Yang-Gang; Yu, Jiang-Yi

2012-03-22

172

Pretreatment with the Total Flavone Glycosides of Flos Abelmoschus manihot and Hyperoside Prevents Glomerular Podocyte Apoptosis in Streptozotocin-Induced Diabetic Nephropathy  

PubMed Central

Abstract Diabetic nephropathy (DN) is an important diabetic complication, and podocyte apoptosis plays a critical role in the development of DN. In the present study, we examined the preventive effect of the total flavone glycosides of Flos Abelmoschus manihot (TFA) on urinary microalbumin and glomerular podocyte apoptosis in experimental DN rats. The preliminary oral administration of TFA (200?mg/kg/day) for 24 weeks significantly decreased the urinary microalbumin to creatinine ratio and 24-h urinary total protein in streptozotocin-induced DN rats. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay indicated glomerular cell apoptosis in DN rats was significantly improved by pretreatment with TFA. Furthermore, fluorescence-activated cell sorting and Hoechst 33342 staining suggested preincubation with hyperoside (50 and 200??g/mL), the major active constituent of TFA, could significantly mitigate cultured podocyte apoptosis induced by the advanced glycation end-products (AGEs). Western blot analysis showed that increased caspase-3 and caspase-8 expressions induced by AGEs were also inhibited by pretreatment with hyperoside at both doses. Our results demonstrate that TFA pretreatment can decrease urinary albumin excretion in early-stage DN, which might be accomplished by preventing renal damage and podocyte apoptosis.

Zhou, Lei; Teng, Shi-Chao; Liu, Jing-Shun; Shang, Wen-Bin; Yuan, Yang-Gang; Yu, Jiang-Yi

2012-01-01

173

Antioxidant and Hepatoprotective Activities of Ethanolic Extracts of Leaves of Premna esculenta Roxb. against Carbon Tetrachloride-Induced Liver Damage in Rats  

PubMed Central

Premna esculenta Roxb. (family Verbenaceae) is a shrub used by the ethnic people of Chittagong Hill Tracts of Bangladesh for the treatment of hepatocellular jaundice. The present study was done to evaluate the hepatoprotective and the in vivo antioxidant activity of ethanolic extracts of leaves of the plant in carbon tetrachloride-induced liver damage in rats. Hepatotoxicity was induced in rats by i.p. injection of CCl4 diluted with olive oil (1:1 v/v; 1 mL/kg body weight) on alternate days for 7 days. After 7 days of pretreatment of test extracts, the biochemical markers such as Serum Glutamate Oxaloacetate Transaminase (SGOT), Serum Glutamate Pyruvate Transaminase (SGPT), Alkaline Phosphatase (ALP), total protein, and albumin were estimated followed by the measurement of liver cytosolic antioxidant enzymes such as superoxide dismutase, catalase, and peroxidase. The data were analyzed using one-way analysis of variance (ANOVA) followed by Dunnett's t-test. The extract both at the doses of 200 and 400 mg/kg p.o. significantly (P < 0.001) reduced the elevated levels of SGPT, SGOT, ALP and increased the reduced levels of total protein and albumin compared to the CCl4-treated animals. The extracts also showed a significant (P < 0.001) increase in the reduced levels of superoxide dismutase (SOD), catalase, and peroxidase. The effects of the extracts on these parameters were comparable with those of the standard, silymarin. The findings of the study indicate that the leaf extract of P. esculenta showed a potential hepatoprotective activity and the protective action might have manifested by restoring the hepatic SOD, catalase, and peroxidase levels. The results justify the traditional use of this plant in liver disorders.

Mahmud, ZA; Bachar, SC; Qais, N

2012-01-01

174

Antioxidant and Hepatoprotective Activities of Ethanolic Extracts of Leaves of Premna esculenta Roxb. against Carbon Tetrachloride-Induced Liver Damage in Rats.  

PubMed

Premna esculenta Roxb. (family Verbenaceae) is a shrub used by the ethnic people of Chittagong Hill Tracts of Bangladesh for the treatment of hepatocellular jaundice. The present study was done to evaluate the hepatoprotective and the in vivo antioxidant activity of ethanolic extracts of leaves of the plant in carbon tetrachloride-induced liver damage in rats. Hepatotoxicity was induced in rats by i.p. injection of CCl4 diluted with olive oil (1:1 v/v; 1 mL/kg body weight) on alternate days for 7 days. After 7 days of pretreatment of test extracts, the biochemical markers such as Serum Glutamate Oxaloacetate Transaminase (SGOT), Serum Glutamate Pyruvate Transaminase (SGPT), Alkaline Phosphatase (ALP), total protein, and albumin were estimated followed by the measurement of liver cytosolic antioxidant enzymes such as superoxide dismutase, catalase, and peroxidase. The data were analyzed using one-way analysis of variance (ANOVA) followed by Dunnett's t-test. The extract both at the doses of 200 and 400 mg/kg p.o. significantly (P < 0.001) reduced the elevated levels of SGPT, SGOT, ALP and increased the reduced levels of total protein and albumin compared to the CCl4-treated animals. The extracts also showed a significant (P < 0.001) increase in the reduced levels of superoxide dismutase (SOD), catalase, and peroxidase. The effects of the extracts on these parameters were comparable with those of the standard, silymarin. The findings of the study indicate that the leaf extract of P. esculenta showed a potential hepatoprotective activity and the protective action might have manifested by restoring the hepatic SOD, catalase, and peroxidase levels. The results justify the traditional use of this plant in liver disorders. PMID:23493235

Mahmud, Za; Bachar, Sc; Qais, N

2012-10-01

175

SPE-HPLC method for the determination of four flavonols in rat plasma and urine after oral administration of Abelmoschus manihot extract.  

PubMed

A SPE-HPLC method was developed and validated for the simultaneous determination of flavonols, isoquercitrin (1), hibifolin (2), myricetin (3), quercetin-3'-O-d-glucoside (4) and quercetin (5) in rat plasma and urine after oral administration of the total flavonoids from Abelmoschus manihot (TFA). The astragalin (6) and kaempferol (7) were used as internal standards (IS). Plasma and urine samples were pretreated by solid-phase extraction using Winchem C(18) reversed-phase cartridges. Analysis of the plasma and urinary extract was performed on YMC-Pack ODS-A C(18) and Thermo ODS-2HYEPRSIL C(18) reversed-phase column, respectively and a mobile phase of acetonitrile-0.1% phosphoric acid was employed. HPLC analysis was conducted with different elution gradients. The flow rate was 1.0 mL/min and the detection wavelength was set at 370 nm. Calibration ranges in plasma for flavonols 2-5 were at 0.011-2.220, 0.014-2.856, 0.022-4.320, and 0.028-5.600 microg/mL, respectively. In urine calibration ranges for flavonols 1, 2, 4 and 5 were at 2.00-16.00, 8.56-102.72, 2.70-21.60, and 3.00-24.00 microg/mL, respectively. The RSD of intra- and inter-day was less than 5.40% and 4.89% in plasma, and less than 3.96% and 6.85% in urine for all the analyses. A preliminary experiment to investigate the plasma concentration and urinary excretion of the flavonols after oral administration of TFA to rats demonstrated that the present method was suitable for determining the flavonols in rat plasma and urine. PMID:17258944

Lai, Xianyin; Zhao, Yuying; Liang, Hong; Bai, Yanjing; Wang, Bin; Guo, Dean

2007-01-10

176

Identification of selenium species in selenium-enriched Lens esculenta plants by using two-dimensional liquid chromatography-inductively coupled plasma mass spectrometry and [ 77Se]selenomethionine selenium oxide spikes  

Microsoft Academic Search

Selenium speciation in Se-enriched Lens esculenta grown in hydroponic culture containing inorganic selenium as Na2SeO3 and Na2SeO4 was performed. After 16 days of growth, the plants were collected and divided in two parts, roots and stems and then analysed to identify and quantify selenium species. Speciation studies of the enzymatic extracts were carried out by using anion-exchange (PRP–X100) and size-exclusion\\/ion-exchange

Zoyne Pedrero; Jorge Ruiz Encinar; Yolanda Madrid; Carmen Cámara

2007-01-01

177

Rhabdias esculentarum n. sp. (Nematoda: Rhabdiasidae) from green frogs of the Rana esculenta species complex in Italy: molecular evidence, morphological description and genetic differentiation from its congeners in frogs and toads.  

PubMed

A new taxon, Rhabdias esculentarum n. sp., is described based on DNA sequence analysis at multiple loci (i.e. mtDNA cox-1, 12S rRNA, ITS-1 and partial ITS-2 regions of the nuclear rDNA) and morphometric analysis carried out on specimens collected from the green frogs of the Rana esculenta species complex in Italy (i.e. R. lessonae Camerano and R. esculenta Linnaeus, identified genetically by diagnostic allozyme loci). Rhabdias esculentarum n. sp. was differentiated genetically, at both mitochondrial and nuclear levels, from Rh. bufonis (Schrank, 1788) (sensu Hartwich, 1972) and Rh. sphaerocephala Goodey, 1924 recovered from the toad Bufo bufo Linnaeus collected sympatrically with the specimens of Rana lessonae and R. esculenta examined in the present study. Moreover, the new taxon proved to be different from the other species of Rhabdias from anurans, which had previously been sequenced using the same genes and deposited in GeneBank. Phylogenetic analyses (MP and ML) inferred from mitochondrial (mtDNA cox-1 and 12S ribosomal RNA) and nuclear (ITS-1 and ITS-2 of the rDNA regions) sequences datasets were congruent in depicting Rh. esculentarum n. sp. as forming a highly supported clade distinct from the sympatric species Rh. bufonis, as well as from Rh. sphaerocephala, characterised on the basis of the same loci. Morphometric analysis and the differential diagnosis of genetically characterised specimens of the new species have revealed differences in several features in comparison with the type-species, Rh. bufonis. Material of the latter species included voucher specimens from Germany deposited by Hartwich (1972) and other specimens collected from B. bufo in Italy. Among the diagnostic characters, the particular cup-shaped buccal capsule characterising Rh. esculentarum is clearly different from the tear-shaped buccal capsule observed in material of R. bufonis obtained from Berlin Museum and collected in the same geographical area as the green frogs under study. Rh. esculentarum was also found to differ in some measurements and allometric characters from Rh. bufonis (sensu Moravec et al., 1997). The data so far collected appear to indicate a host-preference of Rh. esculentarum for Rana lessonae and R. esculenta, which belong to the R. esculenta hybridogenetic species complex in Italy. PMID:22581250

Cipriani, Paolo; Mattiucci, Simonetta; Paoletti, Michela; Santoro, Mario; Nascetti, Giuseppe

2012-05-13

178

Developmental plasticity and biomechanics of treelets and lianas in Manihot aff. quinquepartita (Euphorbiaceae): a branch-angle climber of French Guiana  

PubMed Central

Background and Aims Most tropical lianas have specialized organs of attachment such as twining stems, hooks or tendrils but some do not. Many climbers also have an early self-supporting phase of growth and in some species this can produce treelet-sized individuals. This study focuses on how a liana can climb without specialized attachment organs and how biomechanical properties of the stem are modulated between self-supporting treelets and canopy-climbing lianas. Methods Biomechanics and stem development were investigated in self-supporting to climbing individuals of Manihot aff. quinquepartita (Euphorbiaceae) from tropical rain forest at Saül, central French Guiana. Bending tests were carried out close to the site of growth. Mechanical properties, including Young's elastic modulus, were observed with reference to habit type and changes in stem anatomy during development. Key Results This liana species can show a remarkably long phase of self-supporting growth as treelets with stiff, juvenile wood characterizing the branches and main stem. During the early phase of climbing, stiff but unstable stem segments are loosely held in a vertical position to host plants via petiole bases. The stiffest stems – those having the highest values of Young's modulus measured in bending – belonged to young, leaning and climbing stems. Only when climbing stems are securely anchored into the surrounding vegetation by a system of wide-angled branches, does the plant develop highly flexible stem properties. As in many specialized lianas, the change in stiffness is linked to the development of wood with numerous large vessels and thin-walled fibres. Conclusions Some angiosperms can develop highly effective climbing behaviour and specialized flexible stems without highly specialized organs of attachment. This is linked to a high degree of developmental plasticity in early stages of growth. Young individuals in either open or closed marginal forest conditions can grow as substantial treelets or as leaning/climbing plants, depending on the availability of host supports. The species of liana studied differs both in terms of development and biomechanics from many other lianas that climb via twining, tendrils or other specialized attachment organs.

Menard, Lea; McKey, Doyle; Rowe, Nick

2009-01-01

179

InsP3-dependent Ca2+ oscillations linked to activation of voltage-dependent H+ conductance in Rana esculenta oocytes.  

PubMed

In normal medium supplemented with 10 mM tetraethylammonium chloride (TEACl), membrane depolarizations of immature Rana esculenta oocytes elicited an oscillatory outward current associated with a voltage-dependent H+ current (IH+). The voltage threshold of these oscillations was 22 +/- 5 (n = 10). The oscillations were blocked by intracellular injection of ethylene glycol-O,O'-bis-(2-acetaminoethyl)-N,N,N',N'-tetraacetic acid (EGTA), by application of 1 mM of 4-acetamido-4'-isocyanatostilbene-2,2'-disulfonic acid (SITS), by caffeine (1 mM), and by the intracellular injection of heparin, suggesting that they arose from calcium release from inositol trisphosphate (InsP3)-sensitive stores, monitored by a calcium-dependent chloride current (IClCa2+). The oscillations were independent of the external calcium concentration, and the depolarizations did not affect the InsP3 level. Ni2+, a IH+ inhibitor, blocked the oscillations. Extracellular alkalinization, which lowered the voltage threshold of IH+ and increased its amplitude, also lowered the voltage threshold of the oscillations and increased their amplitude, whereas extracellular acidification produced opposite effects. We suggest that the oscillations are linked to activation of IH+ through a pH-dependent sensitization of InsP3 receptors. PMID:8911687

Humez, S; Collin, T; Matifat, F; Guilbault, P; Fournier, F

1996-08-01

180

Melanosome transfer evaluation by quantitative measurement of Pmel 17 in human normal melanocyte-keratinocyte co-cultures: effect of an Alaria esculenta extract.  

PubMed

Numerous strategies have been proposed to evaluate melanosome transfer. Methods allowing quantitative measurements of this transfer in human normal cellular models, however, are very few and often require extremely specialized devices that are expensive and difficult to use. As a part of the melanosome-specific membrane-bound glycoprotein, Pmel 17 is released from the melanosome membrane by ectodomain shedding. We reasoned, therefore, that it should be possible to evaluate melanosome transfer by quantifying this "soluble" Pmel 17. The Pmel 17 ELISA assay developed permits a detection of 10 to 1000 ng/ml of this glycoprotein in human normal melanocyte-keratinocyte co-culture media. As expected, niacinamide, a well-known melanosome transfer inhibitor, significantly reduced the Pmel 17 quantities found in the culture media. This validated our experimental design. We then used our model to show that a whitening cosmetic active compound, i.e., an Alaria esculenta extract, can (at least in part) enable a significant decrease in the melanosome transfer to produce a lightening effect without affecting melanin production. This research provides a simple and efficient method to quantify melanosome transfer in a human normal co-culture model. It is a particularly useful tool with which to facilitate the development of new active whitening compounds. PMID:23193692

Verdy, Clotilde; Branka, Jean-Eric; Mekideche, Nicole

181

Quantitative assessment of lactate and progerin production in normal human cutaneous cells during normal ageing: effect of an Alaria esculenta extract.  

PubMed

Anti-ageing products are of a great importance in cosmetic fields. However, even if numerous strategies have been proposed to fight against skin ageing or to minimize its aesthetic impact since the beginning of the 'scientific cosmetology' era, the products basing their efficacy on the observation of pathological situations are rare. The most obvious pathology linked to the ageing of skin (notably) consists in the Hutchinson-Gilford Progeria Syndrome (HGPS), a rare disorder characterized by accelerated ageing and early death. In this disease the lamin A, a protein participating (with others lamins) in the formation of the nuclear lamina and implicated in nuclear stability, chromatin structure and gene expression, is present in a truncated version called progerin. In this study, we have examined the lactate and the progerin production of human normal cutaneous cells issued from subjects of different ages. Using a sensitive and specific progerin ELISA assay developed in house, we so provide the first quantitative demonstration of an increased progerin expression and lactate production in skin during ageing. Moreover, we have also demonstrated that in the selected experimental conditions, it was possible to down-regulate the progerin production of aged cells by using an algae extract. As this extract, an Alaria esculenta extract, could be used in cosmetic formulations, we suggest that a better understanding of the skin pathologies could be a useful tool in developing efficient active compounds, attractive for but not limited to cosmetic purposes. PMID:21535442

Verdy, C; Branka, J-E; Mekideche, N

2011-05-03

182

Agrobacterium tumefaciens-mediated transformation of taro (Colocasia esculenta (L.) Schott) with a rice chitinase gene for improved tolerance to a fungal pathogen Sclerotium rolfsii.  

PubMed

Taro (Colocasia esculenta) is one of the most important crops in the Pacific Islands, however, taro yields have been declining in Hawaii over the past 30 years partly due to diseases caused by oomycete and fungal pathogens. In this study, an efficient Agrobacterium tumefaciens-mediated transformation method for taro is first reported. In total, approximately 200 pieces (8 g) of embryogenic calluses were infected with the super-virulent A. tumefaciens strain EHA105 harboring the plant transformation plasmid pBI121/ricchi11 that contains the rice chitinase gene ricchi11. The presence and expression of the transgene ricchi11 in six independent transgenic lines was confirmed using polymerase chain reaction (PCR) and reverse transcription-PCR (RT-PCR). Southern blot analysis of the six independent lines indicated that three out of six (50%) had integrated a single copy of the transgene, and the other three lines had two or three copies of the transgene. Compared to the particle bombardment transformation of taro method, which was used in the previous studies, the Agrobacterium-mediated transformation method obtained 43-fold higher transformation efficiency. In addition, these six transgenic lines via Agrobacterium may be more effective for transgene expression as a result of single-copy or low-copy insertion of the transgene than the single line with multiple copies of the transgene via particle bombardment. In a laboratory bioassay, all six transgenic lines exhibited increased tolerance to the fungal pathogen Sclerotium rolfsii, ranging from 42 to 63% reduction in lesion expansion. PMID:18301900

He, Xiaoling; Miyasaka, Susan C; Fitch, Maureen M M; Moore, Paul H; Zhu, Yun J

2008-02-27

183

Effects of maturation and acidosis on the chaos-like complexity of the neural respiratory output in the isolated brainstem of the tadpole, Rana esculenta  

PubMed Central

Human ventilation at rest exhibits mathematical chaos-like complexity that can be described as long-term unpredictability mediated (in whole or in part) by some low-dimensional nonlinear deterministic process. Although various physiological and pathological situations can affect respiratory complexity, the underlying mechanisms remain incompletely elucidated. If such chaos-like complexity is an intrinsic property of central respiratory generators, it should appear or increase when these structures mature or are stimulated. To test this hypothesis, we employed the isolated tadpole brainstem model [Rana (Pelophylax) esculenta] and recorded the neural respiratory output (buccal and lung rhythms) of pre- (n = 8) and postmetamorphic tadpoles (n = 8), at physiologic (7.8) and acidic pH (7.4). We analyzed the root mean square of the cranial nerve V or VII neurograms. Development and acidosis had no effect on buccal period. Lung frequency increased with development (P < 0.0001). It also increased with acidosis, but in postmetamorphic tadpoles only (P < 0.05). The noise-titration technique evidenced low-dimensional nonlinearities in all the postmetamorphic brainstems, at both pH. Chaos-like complexity, assessed through the noise limit, increased from pH 7.8 to pH 7.4 (P < 0.01). In contrast, linear models best fitted the ventilatory rhythm in all but one of the premetamorphic preparations at pH 7.8 (P < 0.005 vs. postmetamorphic) and in four at pH 7.4 (not significant vs. postmetamorphic). Therefore, in a lower vertebrate model, the brainstem respiratory central rhythm generator accounts for ventilatory chaos-like complexity, especially in the postmetamorphic stage and at low pH. According to the ventilatory generators homology theory, this may also be the case in mammals.

Samara, Ziyad; Fiamma, Marie-Noelle; Bautin, Nathalie; Ranohavimparany, Anja; Le Coz, Patrick; Golmard, Jean-Louis; Darre, Pierre; Zelter, Marc; Poon, Chi-Sang; Similowski, Thomas

2011-01-01

184

Simple sequence repeat marker diversity in cassava landraces: genetic diversity and differentiation in an asexually propagated crop  

Microsoft Academic Search

Cassava ( Manihot esculenta) is an allogamous, vegetatively propagated, Neotropical crop that is also widely grown in tropical Africa and Southeast Asia. To elucidate genetic diversity and differentiation in the crop's primary and secondary centers of diversity, and the forces shaping them, SSR marker variation was assessed at 67 loci in 283 accessions of cassava landraces from Africa (Tanzania and

M. A. Fregene; M. Suarez; J. Mkumbira; H. Kulembeka; E. Ndedya; A. Kulaya; S. Mitchel; U. Gullberg; H. Rosling; A. G. O. Dixon; R. Dean; S. Kresovich

2003-01-01

185

Cassava green mites: A challenge for experts in biological control  

Microsoft Academic Search

Portuguese traders introduced cassava (Manihot esculenta Crantz) from South America to Africa in the 16th century. Since then, it has become an increasingly important food source in an area ranging from 15 ° N to 20 ° S, the so-called cassava belt. Nowadays, its storage roots form an important source of carbohydrates for over 200 million people (Herren and Bennett,

A. Janssen; J. S. Yaninek

1993-01-01

186

Mercury and arsenic pollution in soil and biological samples around the mining town of Obuasi, Ghana  

Microsoft Academic Search

Samples of soils, plantain (Musa paradisiaca), water fern (Ceratopteris cornuta), elephant grass (Pennisetum purpureum), cassava (Manihot esculenta) and mud fish (Heterobranchus bidorsalis) were collected from Obuasi and its environs, which is the most active gold mining town in Ghana. The distribution of mercury and arsenic in these samples from fourteen sampling sites was determined. The annual average surficial soil concentrations

E. H. Amonoo-Neizer; David Nyamah; S. B. Bakiamoh

1996-01-01

187

Productivity of an Intercropped Sweet Orange Orchard in Southwestern Nigeria  

Microsoft Academic Search

At Ibadan southwestern Nigeria, juvenile Agege 1 sweet orange (Citrus sinensis) trees were intercropped with cassava (Manihot esculenta Crantz) + maize (Zea mays L.), egusi melon (Citrullus lanatus L.) followed by soyabeans (Glycine max (L.) Meril), or chilli pepper Capsicum frutescence L.) + amaranthus (Amaranthus caudatus L.) for four consecutive years. The aim was to determine an intercropping option which

I. O. O. Aiyelaagbe

2001-01-01

188

Effect of heat–moisture treatment on the structure and physicochemical properties of tuber and root starches  

Microsoft Academic Search

Starch from tubers potato (Solanum tuberosum), taro (Alocassia indica), new cocoyam (Xanthosoma sagitifolium), true yam (Dioscorea alata), and root cassava, (Manihot esculenta) crops was isolated and its morphology, composition and physicochemical properties were investigated before and after heat–moisture treatment (HMT) (100°C, for 10h at a moisture content of 30%). Native starch granules were round to oval to polygonal with smooth

A Gunaratne; R Hoover

2002-01-01

189

Recent progress in the characterization of molecular determinants in the Xanthomonas axonopodis pv. manihotis –cassava interaction  

Microsoft Academic Search

Cassava bacterial blight, caused by Xanthomonas axonopodis pv. manihotis (Xam), is a widespread disease that affects cassava (Manihot esculenta Crantz). Studies on the pathogen population structure, pathogen diagnosis, identification and expression of plant genes involved in resistance have been carried out. Different molecular techniques were developed to assess the genetic diversity among the Xampopulations. Characterization of Xam population dynamics over

Valérie Verdier; Silvia Restrepo; Gloria Mosquera; Véronique Jorge; Camilo Lopez

2004-01-01

190

Leaf retention and cassava productivity  

Microsoft Academic Search

Increased longevity of leaves, or improved leaf retention, has been suggested as a possible means to increase productivity of cassava (Manihot esculenta Crantz). This study evaluated variation in leaf retention and its relation to cassava productivity under irrigated and stressed conditions. In the first trial 1350 clones were evaluated on the North Coast of Colombia with a 5-month dry period

J. I. Lenis; F. Calle; G. Jaramillo; J. C. Perez; H. Ceballos; J. H. Cock

2006-01-01

191

Photosynthesis in Drought-Adapted Cassava  

Microsoft Academic Search

After 45 d of limited water supply, cassava (Manihot esculenta Crantz) exhibited pronounced reduction in shoot growth, high leaf fall, and decreased stomatal conductance. However, the water status of the remaining leaves was unaffected. This was combined with an amplified heliotropic response and drooping which minimises radiant energy interception at mid-day, suggesting that leaves are sensitive to high irradiance (I).

P.-A. Calatayud; E. Llovera; J. F. Bois; T. Lamaze

2000-01-01

192

Development and application of transgenic technologies in cassava  

Microsoft Academic Search

The capacity to integrate transgenes into the tropical root crop cassava (Manihot esculenta Crantz) is now established and being utilized to generate plants expressing traits of agronomic interest. The tissue culture and gene transfer systems currently employed to produce these transgenic cassava have improved significantly over the past 5 years and are assessed and compared in this review. Programs are

Nigel Taylor; Paul Chavarriaga; Krit Raemakers; Dimuth Siritunga; Peng Zhang

2004-01-01

193

Cassava brown streak disease: A review of present knowledge and research needs  

Microsoft Academic Search

Cassava (Manihot esculenta) is an important subsistence food crop in Africa where it is affected by two main virus diseases, cassava mosaic disease (CMD) and cassava brown streak disease (CBSD). CMD occurs in all the cassava-growing countries on the continent and it has been much researched. CBSD occurs mainly on the East African coast, and although the disease was first

RJ Hillocks; DL Jennings

2003-01-01

194

Transmission studies with Cassava brown streak Uganda virus ( Potyviridae: Ipomovirus) and its interaction with abiotic and biotic factors in Nicotiana benthamiana  

Microsoft Academic Search

Cassava brown streak disease (CBSD), caused by two distinct species, Cassava brown streak Uganda virus (CBSUV) and Cassava brown streak virus (CBSV), is a major constraint to cassava (Manihot esculenta Crantz) production in Africa. Absence of infectious clones of CBSUV or CBSV and the lack of efficient means of mechanical transmission of CBSD has hampered laboratory studies of this disease.

Emmanuel Ogwok; Basavaprabhu L. Patil; Titus Alicai; Claude M. Fauquet

2010-01-01

195

An EST resource for cassava and other species of Euphorbiaceae  

Microsoft Academic Search

Cassava (Manihot esculenta) is a major food staple for nearly 600 million people in Africa, Asia, and Latin America. Major losses in yield result from biotic and abiotic stresses that include diseases such as Cassava Mosaic Disease (CMD) and Cassava Bacterial Blight (CBB), drought, and acid soils. Additional losses also occur from deterioration during the post-harvest storage of roots. To

James V. Anderson; Michel Delseny; Martin A. Fregene; Veronique Jorge; Camilo Lopez; Silvia Restrepo; Mauricio Soto; Benoit Piegu; Valerie Verdier; Richard Cooke; Joe Tohme; David P. Horvath

2004-01-01

196

Impact of water stress on yield and quality of cassava starch  

Microsoft Academic Search

Cassava (Manihot esculenta Crantz) is an important source of industrial raw materials. Products obtained from cassava include chip\\/pellets for animal feed and starch. Important for major industrial uses are the amount and quality of starch obtained from this crop. Production efficiency, including yield and quality of starch, from cassava is markedly influenced by environmental conditions, especially water stress during early

Vilai Santisopasri; Kanjana Kurotjanawong; Sunee Chotineeranat; Kuakoon Piyachomkwan; Klanarong Sriroth; Christopher G Oates

2001-01-01

197

Response of Cassava Leaf Area Expansion to Water Deficit: Cell Proliferation, Cell Expansion and Delayed Development  

Microsoft Academic Search

Background and Aims Cassava (Manihot esculenta) is an important food crop in the tropics that has a high growth rate in optimal conditions, but also performs well in drought-prone climates. The objectives of this work were to determine the effects of water deficit and rewatering on the rate of expansion of leaves at different developmental stages and to evaluate the

ALFREDO A. C. ALVES; TIM L. SETTER

2004-01-01

198

Response of Cassava Leaf Area Expansion to Water Deficit: Cell Proliferation, Cell Expansion and Delayed Development  

Microsoft Academic Search

Background and Aims Cassava (Manihot esculenta) is an important food crop in the tropics that has a high growth rate in optimal conditions, but also performs well in drought-prone climates. The objectives of this work were to determine the effects of water deficit and rewatering on the rate of expansion of leaves at different developmental stages and to evaluate the

ALFREDO A. C. A LVES; L. S ETTER

199

ANALYSIS OF BIOLOGICAL CONTROL OF CASSAVA PESTS IN AFRICA. 111. CASSAVA GREEN MITE MONONYCHELLUS TANAJOA  

Microsoft Academic Search

SUMMARY (1) The interactions of cassava green mite, Mononychellus tanajoa (Bondar) s.l., and cassava, Manihot esculenta Crantz, under West African weather and soil conditions were examined using a simulation model. (2) Field studies had demonstrated the effects of plant and leaf age and rainfall-induced mortality on M. tanajoa population growth. In the absence of effective natural enemies, the model explains,

A. P. GUTIERREZ; J. S. YANINEK; B. WERMELINGER; H. R HERREN; C. K. ELLIS

200

Growth Responses of Micropropagated Cassava Clones as Affected by Glomus Intraradices Colonization  

Microsoft Academic Search

This study reports the effectiveness of an arbuscular mycorrhizal (AM) fungus Glomus intraradices on three clones (SOM-1, 05 and 50) of cassava (Manihot esculenta). Arbuscular mycorrhizal inoculation increased plant resistance to transplant stress from “in vitro” to “ex vitro” conditions and plant biomass (shoot and root) production was greatly enhanced by AM-colonization. The magnitude of AM growth stimulation over control

Carlos Luis Carretero; Manuel Cantos; José Luis García; Rosario Azcón; Antonio Troncoso

2009-01-01

201

Abscisic acid accumulation and osmotic adjustment in cassava under water deficit  

Microsoft Academic Search

Three cassava (Manihot esculenta) genotypes were grown in greenhouse conditions and subjected to water deficit treatments to: (a) assess the extent to which abscisic acid (ABA) and osmotically active solutes accumulate in cassava leaves during water deficit and solute contributions to osmotic adjustment (OA), and (b) determine whether cassava leaves substantially increase their content of dehydrin-like polypeptides during water deficit.

Alfredo A. C Alves; Tim L Setter

2004-01-01

202

Leaf gas exchange of cassava as affected by quality of planting material and water stress  

Microsoft Academic Search

Field trial was conducted to study the effects of quality of planting material and prolonged water stress on leaf gas exchange of the cassava (Manihot esculenta Crantz) cultivar M Col 1684. Nutrient contents of planting material affected rootlet formation, but not leaf gas exchange. Net photosynthetic rate (PN), stomatal conductance (gs), and intercellular CO2 concentration (Ci) were significantly reduced by

M. G. Cayón; M. A. El-Sharkawy; L. F. Cadavid

1997-01-01

203

Plant productivity in cassava-based mixed cropping systems in Colombian hillside farms  

Microsoft Academic Search

In the Colombian hillsides cassava (Manihot esculenta Crantz) is cultivated because of its ability to produce high yields on acidic soils poor in nutrients. Farmers often plant mixtures of cassava cultivars, while bush-beans or maize are traditionally grown as cassava-intercrops. The objectives of this study were: (a) to determine if cassava or overall production can be improved by planting cassava

G. C. Daellenbach; P. C. Kerridge; M. S. Wolfe; E. Frossard; M. R. Finckh

2005-01-01

204

Relative uptake of 32 P by cassava, banana, elephant foot yam and groundnut in intercropping systems  

Microsoft Academic Search

Absorption of applied32P by the treated as well as neighbouring plants in two- and three-crop intercropping systems involving cassava (Manihot esculenta Crantz), banana (Musa (AAB) ‘Mysore’), elephant foot yam (Amorphophallus campanulatus Blume) and groundnut (Arachis hypogaea L.) was studied in field trials. Radiophosphorus applied to the root zone of one of the component species in the mixed systems was found

P. K. Ashokan; P. A. Wahid; C. Sreedharan

1988-01-01

205

Carbon from Cassava peel, an agricultural waste, as an adsorbent in the removal of dyes and metal ions from aqueous solution  

Microsoft Academic Search

Cassava (Manihot esculenta) is a short lived erect perennial shrub, planted vegetatively from hard wood stem cuttings. It is an important crop across a wide range of tropical environments and is a significant component of cropping systems. Cassava peel is an agricultural waste from the food processing industry. Activated carbons prepared from waste cassava peel employing physical and chemical methods

S Rajeshwarisivaraj; S Sivakumar; P Senthilkumar; V Subburam

2001-01-01

206

Isolation and expression in transgenic tobacco and rice plants, of the cassava vein mosaic virus (CVMV) promoter  

Microsoft Academic Search

The cassava vein mosaic virus (CVMV) is a double stranded DNA virus which infects cassava plants (Manihot esculenta Crantz) and has been characterized as a plant pararetrovirus belonging to the caulimovirus subgroup. Two DNA fragments, CVP1 of 388 nucleotides from position -368 to +20 and CVP2 of 511 nucleotides from position -443 to +72, were isolated from the viral genome

Bertrand Verdaguer; Alexandre de Kochko; Roger N. Beachy; Claude Fauquet

1996-01-01

207

Improvement of somatic embryogenesis and plant recovery in cassava  

Microsoft Academic Search

Methods for improving the efficiency of plant recovery from somatic embryos of cassava (Manihot esculenta Crantz) were investigated by optimizing the maturation regime and incorporating a desiccation stage prior to inducing germination. Somatic embryos were induced from young leaf lobes of in vitro grown shoots of cassava on Murashige and Skoog medium with 2,4-dichlorophenoxy acetic acid. After 15 to 20

Helena Mathews; C. Schopke; R. Carcamo; P. Chavarriaga; C. Fauquet; R. N. Beachy

1993-01-01

208

Cassava: a basic energy source in the tropics  

Microsoft Academic Search

Cassava (Manihot esculenta) is the fourth most important source of food energy in the tropics. More than two-thirds of the total production of this crop is used as food for humans, with lesser amounts being used for animal feed and industrial purposes. The ingestion of high levels of cassava has been associated with chronic cyanide toxicity in parts of Africa,

J. H. Cock

1982-01-01

209

Identification of the potential active components of Abelmoschus manihot in rat blood and kidney tissue by microdialysis combined with ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry.  

PubMed

In this paper, microdialysis combining with ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was applied to simultaneously identify components in blood and kidney dialysis after oral administration of Abelmoschus manihot extract. Microdialysis probe was implanted in the jugular vein and the kidney medulla, respectively; microdialysis samples were collected continuously, transferred to microtubes and analyzed by UPLC-Q-TOF/MS. The components in microdialysis samples were separated by an UPLC HSS T3 column and eluted with acetonitrile and water (containing 0.1% formic acid) at a flow rate of 0.4 mL/min. The results showed that unbound constituents in blood circulation of the rat include hyperoside, isoquercitrin, quercetin monoglucuronide, quercetin-3'-O-glucoside, quercetin, myricetin, and hibifolin while unbound constituents in kidney are hyperoside, isoquercitrin, quercetin monoglucuronide, which might be the potential active components in vivo. The developed method was simple and reliable, and could be adopted to rapidly screen and identify potential active components contributing to pharmacological effects of TCM and to better clarify its action mechanism. PMID:21247814

Xue, Caifu; Guo, Jianming; Qian, Dawei; Duan, Jin-ao; Shang, Erxin; Shu, Yan; Lu, Yuwei

2010-12-28

210

Identification of selenium species in selenium-enriched Lens esculenta plants by using two-dimensional liquid chromatography-inductively coupled plasma mass spectrometry and [77Se]selenomethionine selenium oxide spikes.  

PubMed

Selenium speciation in Se-enriched Lens esculenta grown in hydroponic culture containing inorganic selenium as Na(2)SeO(3) and Na(2)SeO(4) was performed. After 16 days of growth, the plants were collected and divided in two parts, roots and stems and then analysed to identify and quantify selenium species. Speciation studies of the enzymatic extracts were carried out by using anion-exchange (PRP-X100) and size-exclusion/ion-exchange (Shodex Asahipak) columns coupled to inductively coupled plasma mass spectrometry (ICP-MS). The need of using two independent chromatographic mechanisms for unambiguous species identification is demonstrated. Moreover, the use of a [(77)Se]selenomethionine selenium oxide spike turned out to be critical to discriminate between selenium selenomethioine selenium oxide and selenocysteine. PMID:17140591

Pedrero, Zoyne; Encinar, Jorge Ruiz; Madrid, Yolanda; Cámara, Carmen

2006-11-30

211

Synthesis of periclinal chimera in cassava.  

PubMed

We provide the first report on the synthesis of a very productive interspecific periclinal chimera of cassava, with large and edible roots. The epidermal tissue of the chimera was formed by the cultivated species Manihot esculenta (E), and the subepidermis and internal tissue were formed by the wild species, Manihot fortalezensis (F). We used cytogenetics and morphological analyses to determine the origins of all tissues. These results may offer potential for the development of new lines for crop improvement based on the use of chimera composed of different combinations of wild species and cultivars. PMID:23512678

Nassar, N M A; Bomfim, N

2013-02-27

212

Oral Presentation Effects of Ultraviolet Radiation and Temperature on Characteristics of Modified Cassava Starch  

Microsoft Academic Search

Cassava starch ( Manihot esculenta ) was soaked in 1% lactic acid solution and distilled water at 30°C for 16 hours. The suspensio ns then were drained, divided into 5 portions and treated for 6 hours under following co nditions: a 60°C hot air oven, artificial ultraviolet (UV, lamda = 254 nm), sun-drying, sun-d rying with double-layer glasses, and a

Suthaya Phimphilai; Oratai Chumnan; Kajorndaj Phimphilai; A. Sansai

213

Five native tree species and manioc under slash-and-mulch agroforestry in the eastern Amazon of Brazil: plant growth and soil responses  

Microsoft Academic Search

Throughout the Amazon of Brazil, manioc (Manihot esculenta) is a staple crop produced through slash-and-burn agriculture. Nutrient losses during slash-and-burn can be large and nutrient\\u000a demand by food crops so great that fields are often abandoned after two years. In recent decades, farmers have reduced the\\u000a fallow phase from 20 to ~5 years, limiting plant nutrient accumulation to sustain crop yields.

Aaron H. Joslin; Daniel Markewitz; Lawrence A. Morris; Francisco DeAssis Oliveira; Ricardo O. Figueiredo; Oswaldo R. Kato

2011-01-01

214

Comparison of NAA and 2,4-D induced somatic embryogenesis in Cassava  

Microsoft Academic Search

NAA and 2,4-D were compared for their ability to induce somatic embryogenesis in cassava (Manihot esculenta Crantz). In all seven cultivars tested, only 2,4-D had the capacity to induce primary somatic embryos from leaf explants,\\u000a however, both NAA and 2,4-D were capable of inducing secondary somatic embryos. More secondary somatic embryos were formed\\u000a in NAA than in 2,4-D medium. Furthermore,

E. Sofiari; C. J. J. M. Raemakers; E. Kanju; K. Danso; A. M. van Lammeren; E. Jacobsen; R. G. F. Visser

1997-01-01

215

Kinetics of thermal softening of cassava tubers and rheological modeling of the starch  

Microsoft Academic Search

Cassava or tapioca (Manihot esculenta Crantz) tubers having high amount of carbohydrate are utilized after boiling or processing into starch and flour. Textural\\u000a properties of raw and cooked tubers depend on variety, maturity, growing environment, physico-chemical and starch properties.\\u000a Starch is used in food preparations as gelling and thickening agent, stabilizer and texture modifier. This study aims at analyzing\\u000a and

Moothandassery Sankarakutty Sajeev; J. Sreekumar; M. Unnikrishnan; S. N. Moorthy; S. Shanavas

2010-01-01

216

Identification and Characterization of the Cassava Core-Clock Gene EARLY FLOWERING 4  

Microsoft Academic Search

The angiosperm circadian clock has been well established from molecular-genetic studies in a temperate plant model. Conservation\\u000a of clock function is less explored in plants from the tropics. Cassava (Manihot esculenta) is a staple crop grown in the tropics that has been of limited research interest, and more generally, research on photoperiod\\u000a and clock genes has been sparse. EARLY FLOWERING

Oluwabusayo Sarah Adeyemo; Elsebeth Kolmos; Joe Tohme; Paul Chavariaga; Martin Fregene; Seth J. Davis

2011-01-01

217

PIG-mediated cassava transformation using positive and negative selection  

Microsoft Academic Search

In order to develop new selection systems for production of transgenic cassava (Manihot esculenta Crantz), two different selection regimes were assessed for their efficiency on regeneration of transgenic cassava plants:\\u000a positive selection using mannose and negative selection using hygromycin. Explants from somatic cotyledons and embryogenic\\u000a suspensions were used as target tissues in the transformation experiments and bombarded using the particle

P. Zhang; J. Puonti-Kaerlas

2000-01-01

218

Multiplex RT-PCR assays for the simultaneous detection of both RNA and DNA viruses infecting cassava and the common occurrence of mixed infections by two cassava brown streak viruses in East Africa  

Microsoft Academic Search

Uniplex and multiplex reverse transcription-polymerase chain reaction (RT-PCR) protocols were developed for the detection of cassava brown streak viruses (CBSVs) in single and mixed infections with cassava mosaic begomoviruses (CMBs) in a tropical crop plant, cassava (Manihot esculenta). CMBs contain ssDNA as their genome (genus Begomovirus, family Geminiviridae) while CBSVs are made up of positive sense ssRNA (genus Ipomovirus, family

M. M. Abarshi; I. U. Mohammed; S. C. Jeremiah; J. P. Legg; P. Lava Kumar; R. J. Hillocks; M. N. Maruthi

219

Occurrence of lace bug Vatiga illudens and Vatiga manihotae (Hemiptera: Tingidae) in Mato Grosso do Sul, midwestern Brazil.  

PubMed

Nymphs and adults of the lace bug (Hemiptera: Tingidae) have been found in cassava crops (Manihot esculenta) in Mato Grosso do Sul State, Brazil. The insects were collected in the field and taken to the laboratory where they were identified based on some morphological traits of the species Vatiga manihotae (Drake) and V. illudens (Drake), which are first reported in the aforementioned state. PMID:22886161

Bellon, Patrícia P; Wengrat, Ana P G S; Kassab, Samir O; Pietrowski, Vanda; Loureiro, Elisângela S

2012-09-01

220

The Performance of Viruliferous and Non-Viruliferous Cassava Biotype Bemisia tabaci on Amino Acid Diets  

Microsoft Academic Search

\\u000a The role of amino acids is examined through a determination of their ­influence on Bemisia tabaci survival, honeydew secretion and oviposition. B. tabaci\\u000a showed better performance when feeding on a diet of 20 amino acids more mimicking cassava host plants (Manihot esculenta Crantz.) as opposed to elevated levels of the amino acids. On a concentration range, 80% survival was observed

Winston M. O. Thompson

221

Broad Spectrum Resistance to ssDNA Viruses Associated with Transgene-Induced Gene Silencing in Cassava  

Microsoft Academic Search

Geminiviruses are ssDNA viruses that infect a range of economically important crop species. We have developed a pathogen-derived\\u000a transgenic approach to generate high levels of resistance against these pathogens in a susceptible cultivar of cassava (Manihot esculenta). Integration of the AC1 gene (which encodes the replication-associated protein) from African cassava mosaic virus imparted resistance against the\\u000a homologous virus and provided

Padmanabhan Chellappan; Munyaradzi V. Masona; Ramachandran Vanitharani; Nigel J. Taylor; Claude M. Fauquet

2004-01-01

222

Preparation and characterization of blends of recycled polystyrene with cassava starch  

Microsoft Academic Search

Secondary recycling is an alternative to solve at least part of the worldwide pollution problem caused by persistence of petrochemical\\u000a plastic materials in the environment. In this work we report the secondary recycling of disposable polystyrene (PS) using\\u000a cassava starch (Manihot esculenta Crantz) and a natural plasticizer extracted from a palm tree of the Amazon: Buriti (Mauritia flexuosa L.) oil.

Tais A. P. F. Pimentel; Jussara A. Durães; Adriana L. Drummond; Daniela Schlemmer; Rosana Falcão; Maria José Araújo Sales

2007-01-01

223

Response of cassava to water stress  

Microsoft Academic Search

Summary  Cassava (Manihot esculenta Crantz) is a staple food for a large sector of human population in the tropics. It is widely produced for its starchy roots\\u000a by small farmers over a range of environments on poor infertile soils with virtually no inputs. It is highly productive under\\u000a favorable conditions and produces reasonably well under adverse conditions where other crops fail.

Mabrouk A. El-Sharkawy; James H. Cock

1987-01-01

224

Carotenoid Bioavailability of Vegetables and Carbohydrate-containing Foods Measured by Retinol Accumulation in Rat Livers  

Microsoft Academic Search

Cassava (Manihot esculenta), water convolvulus (Ipomea reptans) and brassica (Brassica juncea L) leaves, carrot (Daucus carrota L), and sweet potato (Ipomea batata) were cooked imitating local household preparation while banana (Musa paradisiaca L) was freeze-dried. The prepared foods, each containing 180 ?g ? -carotene, were fed to vitamin A-depleted rats in addition to their vitamin A-depleted diet for 14 days.

Fransiska Zakaria-Rungkat; M. Djaelani; Setiana; E. Rumondang; Nurrochmah

2000-01-01

225

Breeding cassava for resistance to cassava mosaic disease  

Microsoft Academic Search

Cassava mosaic disease (CMD) is one of the most serious and widespread diseases throughout cassava growing areas in Africa, causing yield reductions of up to 90%. Early research on breeding of cassava (Manihot esculentaCrantz) for resistance to CMD in Africa is reviewed. Changes in population size and in activity of the white-fly vector to CMD (Bemisia tabaciGenn.) in relation to

S. K. Hahn; E. R. Terry; K. Leuschner

1980-01-01

226

Indigenous diversity of Cassava: Generation, maintenance, use and loss among the Amuesha, Peruvian upper Amazon  

Microsoft Academic Search

For cassava (Manihot esculenta Euphorbiaceae), results from field collection, semistructured interviews, phenetic and cluster analyses, and Global Information\\u000a Systems (G1S) indicate that cassava phenotypes vary with elevation and topography, but less with soils or pests and diseases.\\u000a Amuesha women with a sense of tradition maintain many cassava varieties along with associated myths, songs, names and indigenous\\u000a production. The shaman plays

Jan Salick; Nicoletta Cellinese; Sandra Knapp

1997-01-01

227

Gourd and squash artifacts yield starch grains of feasting foods from preceramic Peru.  

PubMed

In a study of residues from gourd and squash artifacts, we recovered starch grains from manioc (Manihot esculenta), potato (Solanum sp.), chili pepper (Capsicum spp.), arrowroot (Maranta arundinacea), and algarrobo (Prosopis sp.) from feasting contexts at the Buena Vista site, a central Peruvian preceramic site dating to approximately 2200 calendar years B.C. This study has implications for the study of plant food use wherever gourds or squashes are preserved, documents the earliest evidence for the consumption of algarrobo and arrowroot in Peru, and provides insights into foods consumed at feasts. PMID:19633184

Duncan, Neil A; Pearsall, Deborah M; Benfer, Robert A

2009-07-24

228

Constituents and secondary metabolite natural products in fresh and deteriorated cassava roots.  

PubMed

A phytochemical analysis of cassava (Manihot esculenta Crantz) fresh roots and roots suffering from post-harvest physiological deterioration (PPD) has been carried out. The first isolation and identification of galactosyl diacylglycerides from fresh cassava roots is reported, as well as beta-carotene, linamarin, and beta-sitosterol glucopyranoside. The hydroxycoumarin scopoletin and its glucoside scopolin were identified from cassava roots during PPD, as well as trace quantities of esculetin and its glucoside esculin. There is no isoscopoletin in cassava roots during PPD. PMID:20137795

Bayoumi, Soad A L; Rowan, Michael G; Beeching, John R; Blagbrough, Ian S

2010-04-01

229

Gourd and squash artifacts yield starch grains of feasting foods from preceramic Peru  

PubMed Central

In a study of residues from gourd and squash artifacts, we recovered starch grains from manioc (Manihot esculenta), potato (Solanum sp.), chili pepper (Capsicum spp.), arrowroot (Maranta arundinacea), and algarrobo (Prosopis sp.) from feasting contexts at the Buena Vista site, a central Peruvian preceramic site dating to ?2200 calendar years B.C. This study has implications for the study of plant food use wherever gourds or squashes are preserved, documents the earliest evidence for the consumption of algarrobo and arrowroot in Peru, and provides insights into foods consumed at feasts.

Duncan, Neil A.; Pearsall, Deborah M.; Benfer, Robert A.

2009-01-01

230

The effects of arbuscular mycorrhizal fungal inoculation and mulch of contrasting chemical composition on the yield of cassava under humid tropical conditions.  

PubMed

The influence of arbuscular mycorrhizal fungus (AMF), Glomus deserticola, and leaf mulch from Gliricidia sepium and Senna siamea on the yield of cassava (Manihot esculenta) in a degraded alfisol of southwestern Nigeria was investigated. Inoculation in conjunction with mulching increased cassava tuber yield by 40-278% over the control. The highest yield was obtained with G. sepium and S. siamea mulch applied together in equal proportions. The results are explained in the light of the growth-enhancing effects of AMF, encouraged by the ameliorating effects of mulch on the soil structure and nutrient contents. PMID:20364236

Okon, Iniobong E; Solomon, Marian G; Osonubi, Oluwole

2010-04-01

231

Cassava genetic transformation and its application in breeding.  

PubMed

As a major source of food, cassava (Manihot esculenta Crantz) is an important root crop in the tropics and subtropics of Africa and Latin America, and serves as raw material for the production of starches and bioethanol in tropical Asia. Cassava improvement through genetic engineering not only overcomes the high heterozygosity and serious trait separation that occurs in its traditional breeding, but also quickly achieves improved target traits. Since the first report on genetic transformation in cassava in 1996, the technology has gradually matured over almost 15 years of development and has overcome cassava genotype constraints, changing from mode cultivars to farmer-preferred ones. Significant progress has been made in terms of an increased resistance to pests and diseases, biofortification, and improved starch quality, building on the fundamental knowledge and technologies related to planting, nutrition, and the processing of this important food crop that has often been neglected. Therefore, cassava has great potential in food security and bioenergy development worldwide. PMID:21564542

Liu, Jia; Zheng, Qijie; Ma, Qiuxiang; Gadidasu, Kranthi Kumar; Zhang, Peng

2011-06-22

232

Cassava: an appraisal of its phytochemistry and its biotechnological prospects.  

PubMed

The present state of knowledge of the phytochemistry of small molecules isolated from the roots and leaves of cassava, Manihot esculenta Crantz (Euphorbiaceae), is reviewed. Cassava roots are an important source of dietary and industrial carbohydrates, mainly eaten as a source of starch, forming the staple food to over 500 million; additionally, the roots have value as a raw material for industrial starch production and for animal feed giving the crop high economic value, but it suffers markedly from post-harvest physiological deterioration (PPD). The hydroxycoumarins scopoletin and its glucoside scopolin as well as trace quantities of esculetin and its glucoside esculin are identified from cassava roots during PPD. The biotechnological prospects for cassava are also reviewed including a critical appraisal of transgenic approaches for crop improvement, together with its use for bioethanol production, due to cassava's efficient ability to fix carbon dioxide into carbohydrate. PMID:20943239

Blagbrough, Ian S; Bayoumi, Soad A L; Rowan, Michael G; Beeching, John R

2010-10-11

233

Utilizacion de la Harina de Yuca en Panificacion (Utilization of Yucca Flour in the Making of Bread).  

National Technical Information Service (NTIS)

A plan for substituting up to 20% of wheat flour for yucca flour is explained in this report. A description is given of the equipment, methods, and nutritional characteristics of the final product using yucca flour. Many tables are included for clarity.

O. A. Gordilla

1974-01-01

234

Domestication and defence: Foliar tannins and C/N ratios in cassava and a close wild relative  

NASA Astrophysics Data System (ADS)

Plant domestication is accompanied by shifts in resource allocation, as a result of farmer selection for genotypes that give high yields in agricultural habitats. Relaxed natural selection for chemical and physical defences in these habitats could facilitate resource allocation to yield. We compared the concentrations of tannins, and C/N ratios, which are often correlated with investment in cell-wall compounds, in leaves of landraces of domesticated cassava ( Manihot esculenta) and a close wild relative in French Guiana. Foliar concentrations of tannins were about 1.9 times higher in the wild relative than in domesticated cassava. Histochemical analyses showed that tannins were present in nearly all palisade and spongy parenchyma cells of the wild taxon, but in only some cells of these tissues in M. esculenta. C/N ratios were also 1.9 times higher in leaves of the wild relative than in those of domesticated cassava. Tannins accounted for only a small proportion of total carbon, and the higher C/N ratio in wild than in domesticated cassava may reflect higher investment in carbon-containing compounds additional to tannins, such as cell-wall compounds. The divergence in these traits between cassava and this close wild relative mirrors a broad pattern observed in wild plant species across habitats varying in resource availability. One explanation for our results is that domestication in cassava may have favoured a shift from a resource conservation strategy to a resource acquisition strategy.

Mondolot, Laurence; Marlas, Amandine; Barbeau, Damien; Gargadennec, Annick; Pujol, Benoît; McKey, Doyle

2008-09-01

235

Cassava interspecific hybrids with increased protein content and improved amino acid profiles.  

PubMed

Cassava (Manihot esculenta) is a principal food for large populations of poor people in the tropics and subtropics. Its edible roots are poor in protein and lack several essential amino acids. Interspecific hybrids may acquire high protein characteristics from wild species. We analyzed 19 hybrids of M. esculenta with its wild relative, M. oligantha, for crude protein, amino acid profile, and total cyanide. Some hybrids produced roots with high protein content of up to 5.7%, while the common cultivar that we examined had just 2.3% crude protein. The essential amino acids alanine, phenylalanine, and valine were detected in the hybrids. The sulfur-containing amino acids cysteine and methionine were found at relatively high concentrations in the roots of 4 hybrids. The proportion of lysine in one hybrid was 20 times higher than in the common cultivar. The levels of total cyanide ranged from 19.73 to 172.56 mg/kg and most of the roots analyzed were classified as "non-toxic" and "low toxic". Furthermore, 2 progenies showed reasonable levels of cyanide, but higher protein content and amino acid profile more advantageous than the common cassava. PMID:23661446

Gomes, P T C; Nassar, N M A

2013-04-12

236

Dependency of cassava ( Manihot esculanta Crantz) on vesicular-arbuscular mycorrhizal fungi  

Microsoft Academic Search

Cassava plants were started in the greenhouse either from small cuttings (2.0 mg P\\/cutting) or large cuttings (20.2 mg P\\/cutting) in a subsurface Oxisol not inoculated or inoculated with Glomus aggregatum at target soil solution P concentrations of 0.003–0.2 mg l-1. Vesicular-arbuscular mycorrhizal (VAM) fungal colonization levels in excess of 60% were attained on cassava roots irrespective of the size

M. Habte; M. N. Byappanahalli

1994-01-01

237

Biogas production from blends of cassava (Manihot utilissima) peels with some animal wastes  

Microsoft Academic Search

Cassava peels (CP) obtained after peeling cassava roots were anaerobically digested using 50L capacity fermentor and in blends with some animal wastes. The peels were blended with cow dung (CD), poultry droppings (PD) and swine dung (SD), in the ratio of 1:1. The mean flammable biogas yield of the cassava peels alone was 2.29 ± 0.97L \\/total mass of slurry.

A. U. Ofoefule; E. O. Uzodinma

238

Ontogeny of PAC1-R and VPAC1-R in the frog, Rana esculenta  

Microsoft Academic Search

The distribution of pituitary adenylate cyclase-activating polypeptide (PACAP) and PACAP receptors in the brain of amphibians has been previously described. In the present study, we have investigated the ontogeny of the selective PACAP receptor, PAC1-R, and the PACAP-vasoactive intestinal polypeptide (VIP) mutual receptor, VPAC1-R, in frog embryos by whole-mount in situ hybridization histochemistry. At stage 20, expression of PAC1-R and\\/or

Monica Ciarlo; Federica Bruzzone; Cristiano Angelini; Mauro Vallarino; Hubert Vaudry

2007-01-01

239

Incidence and distribution of viruses of Taro ( Colocasia esculenta ) in Pacific Island countries  

Microsoft Academic Search

Four viruses have been reported from taro; Dasheen mosaic virus (DsMV), Taro bacilliform virus (TaBV) and two putative rhabdoviruses, Colocasia bobone disease virus (CBDV) and Taro vein chlorosis virus (TaVCV). A fifth virus, tentatively named Taro reovirus (TaRV),\\u000a has also been recently identified. The distribution of these viruses throughout the Pacific Islands, and the symptoms associated\\u000a with their infection, are

P. A. Revill; G. V. H. Jackson; G. J. Hafnerc; I. Yang; M. K. Maino; M. L. Dowling; L. C. Devitt; J. L. Dale; R. M. Harding

2005-01-01

240

Variation in Sex Ratio and Evolutionary Rate of Hemiclonal Rana esculenta Populations  

Microsoft Academic Search

In many plant and animal taxa mutation rates are higher in males than in females. As a result, the evolutionary speed of genes\\u000a depends on how much time they spend in either sex. Usually, this time differs between genes located on sex chromosomes but\\u000a not between those on autosomes. Here we present an unusual system with a partially sex-linked inheritance

Christian Som; Heinz-Ulrich Reyer

2006-01-01

241

Action of capsaicin and related peptides on the ionic transport across the skin of Rana esculenta.  

PubMed

Capsaicin at low concentrations increases the short circuit current (SCC) across frog skin. Simultaneous measurements of both transepithelial fluxes of 22Na or 36Cl demonstrate that the SCC increase is due to stimulation of sodium active absorption. Capsaicin acts through the liberation of several peptides; thus these peptides were tested on the SCC across frog skin. Those more active are, in order of potency: Cyclic Calcitonin Gene Related Peptide (CGRP), Kassinin and Eledoisin, Substance P (SP) and Neurokinin A. Neurokinin B and Vasoactive Intestinal Peptide (VIP) have no effect. Also the actions of SP and CGRP are due mainly to stimulation of Na+ active absorption. A strict parallelism regarding the sensitivity to inhibitors (Naproxen, SQ22536 and CP96345) between SP, CGRP and Capsaicin strengthens the hypothesis that SP and CGRP are liberated by Capsaicin in this tissue. PMID:7516733

Lippe, C; Bellantuono, V; Castronuovo, G; Ardizzone, C; Cassano, G

242

Correlation Between Transepithelial Na + Transport and Transepithelial Water Movement Across Isolated Frog Skin ( Rana esculenta )  

Microsoft Academic Search

.   In the present work the coupling under short-circuited conditions between the net Na+-influx across isolated frog skin and the transepithelial transport of water was examined i.e., the short-circuit current\\u000a (I\\u000a \\u000a \\u000a \\u000a sc\\u000a \\u000a ) and the transepithelial water movement (TEWM) were measured simultaneously. It has been shown repeatedly that the I\\u000a \\u000a \\u000a \\u000a sc\\u000a \\u000a across isolated frog skin is equal to the net

R. Nielsen

1997-01-01

243

Análisis Físico-Químico y Morfológico de Almidones de Ñame, Yuca y Papa y Determinación de la Viscosidad de las Pastas  

Microsoft Academic Search

The physicochemical properties, morphology and the viscoamilogrames of yam, potato and cassava native starches were studied. Previous the determinations, the samples were dried up to constant weight. Ash and amylose content, gelatinization temperature and viscosity were lower in cassava; fat showed differences between cassava and potato; water absorption index in yam, potato and cassava showed significant differences. Cooking facility was

Armando Alvis; Carlos A. Vélez; Héctor S. Villada; Maite Rada-Mendoza

2008-01-01

244

Effect of biocontrol agents and biofertilizers on root rot, yield, harvest index and nutrient uptake of cassava (Manihot esculanta Crantz)  

Microsoft Academic Search

Cassava is an important subsidiary food and industrial raw material in the tropics. Root rot disease, caused by Phytophthora palmivora, poses a serious threat to cassava cultivation in Tamil Nadu, India. Field experiments (2008–09) were conducted to study the effect of biocontrol agents (Trichoderma spp. and Pseudomonas fluorescens) and biofertilizers (Azospirillum, vesicular–arbuscular mycorrhizal fungi and phosphorus-solubilizing bacteria) on root rot,

A. C. Hridya; G. Byju; Raj Sekhar Misra

2012-01-01

245

Starch grain evidence for the preceramic dispersals of maize and root crops into tropical dry and humid forests of Panama.  

PubMed

The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800-7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400-5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture. PMID:17360697

Dickau, Ruth; Ranere, Anthony J; Cooke, Richard G

2007-02-21

246

Starch grains reveal early root crop horticulture in the Panamanian tropical forest.  

PubMed

Native American populations are known to have cultivated a large number of plants and domesticated them for their starch-rich underground organs. Suggestions that the likely source of many of these crops, the tropical forest, was an early and influential centre of plant husbandry have long been controversial because the organic remains of roots and tubers are poorly preserved in archaeological sediments from the humid tropics. Here we report the occurrence of starch grains identifiable as manioc (Manihot esculenta Crantz), yams (Dioscorea sp.) and arrowroot (Maranta arundinacea L.) on assemblages of plant milling stones from preceramic horizons at the Aguadulce Shelter, Panama, dated between 7,000 and 5,000 years before present (BP). The artefacts also contain maize starch (Zea mays L.), indicating that early horticultural systems in this region were mixtures of root and seed crops. The data provide the earliest direct evidence for root crop cultivation in the Americas, and support an ancient and independent emergence of plant domestication in the lowland Neotropical forest. PMID:11057665

Piperno, D R; Ranere, A J; Holst, I; Hansell, P

2000-10-19

247

Genome-Wide Discovery and Information Resource Development of DNA Polymorphisms in Cassava  

PubMed Central

Cassava (Manihot esculenta Crantz) is an important crop that provides food security and income generation in many tropical countries, and is known for its adaptability to various environmental conditions. Its draft genome sequence and many expressed sequence tags are now publicly available, allowing the development of cassava polymorphism information. Here, we describe the genome-wide discovery of cassava DNA polymorphisms. Using the alignment of predicted transcribed sequences from the cassava draft genome sequence and ESTs from GenBank, we discovered 10,546 single-nucleotide polymorphisms and 647 insertions and deletions. To facilitate molecular marker development for cassava, we designed 9,316 PCR primer pairs to amplify the genomic region around each DNA polymorphism. Of the discovered SNPs, 62.7% occurred in protein-coding regions. Disease-resistance genes were found to have a significantly higher ratio of nonsynonymous-to-synonymous substitutions. We identified 24 read-through (changes of a stop codon to a coding codon) and 38 premature stop (changes of a coding codon to a stop codon) single-nucleotide polymorphisms, and found that the 5 gene ontology terms in biological process were significantly different in genes with read-through single-nucleotide polymorphisms compared with all cassava genes. All data on the discovered DNA polymorphisms were organized into the Cassava Online Archive database, which is available at http://cassava.psc.riken.jp/.

Yoshida, Takuhiro; Akiyama, Kenji; Ishitani, Manabu; Seki, Motoaki; Shinozaki, Kazuo

2013-01-01

248

The BioCassava plus program: biofortification of cassava for sub-Saharan Africa.  

PubMed

More than 250 million Africans rely on the starchy root crop cassava (Manihot esculenta) as their staple source of calories. A typical cassava-based diet, however, provides less than 30% of the minimum daily requirement for protein and only 10%-20% of that for iron, zinc, and vitamin A. The BioCassava Plus (BC+) program has employed modern biotechnologies intended to improve the health of Africans through the development and delivery of genetically engineered cassava with increased nutrient (zinc, iron, protein, and vitamin A) levels. Additional traits addressed by BioCassava Plus include increased shelf life, reductions in toxic cyanogenic glycosides to safe levels, and resistance to viral disease. The program also provides incentives for the adoption of biofortified cassava. Proof of concept was achieved for each of the target traits. Results from field trials in Puerto Rico, the first confined field trials in Nigeria to use genetically engineered organisms, and ex ante impact analyses support the efficacy of using transgenic strategies for the biofortification of cassava. PMID:21526968

Sayre, Richard; Beeching, John R; Cahoon, Edgar B; Egesi, Chiedozie; Fauquet, Claude; Fellman, John; Fregene, Martin; Gruissem, Wilhelm; Mallowa, Sally; Manary, Mark; Maziya-Dixon, Bussie; Mbanaso, Ada; Schachtman, Daniel P; Siritunga, Dimuth; Taylor, Nigel; Vanderschuren, Herve; Zhang, Peng

2011-01-01

249

Investigation of biosynthetic pathways to hydroxycoumarins during post-harvest physiological deterioration in Cassava roots by using stable isotope labelling.  

PubMed

Cassava (Manihot esculenta Crantz) is an important starch-rich crop, but the storage roots only have a short shelf-life due to post-harvest physiological deterioration (PPD), which includes the over-production and polymerisation of hydroxycoumarins. Key aspects of coumarin secondary-metabolite biosynthesis remain unresolved. Here we exploit the accumulation of hydroxycoumarins to test alternative pathways for their biosynthesis. Using isotopically labelled intermediates (p-coumarate-2-(13)C, caffeate-2-(13)C, ferulate-2-(13)C, umbelliferone-2-(18)O and esculetin-2-(18)O), we show that the major biosynthetic pathway to scopoletin and its glucoside, scopolin, in cassava roots during PPD is through p-coumaric, caffeic and then ferulic acids. An alternate pathway through 2',4'-dihydroxycinnamate and umbelliferone leads to esculetin and esculin. We have used C(18)O(2)-carboxylate-labelled cinnamic and ferulic acids, and feeding experiments under an atmosphere of (18)O(2), to investigate the o-hydroxylation and cyclisation steps. We demonstrate that the major pathway is through o-hydroxylation and not via a proposed spirolactone-dienone intermediate. PMID:19035613

Bayoumi, Soad A L; Rowan, Michael G; Beeching, John R; Blagbrough, Ian S

2008-12-15

250

The time and energy expenditure of indigenous women horticulturalists in the northwest Amazon.  

PubMed

The energy cost of subsistence activities and the daily time and energy budgets of Tatuyo women were assessed as part of a village energy flow study. The Tatuyo are swidden horticulturalists relying on bitter manioc (Manihot esculenta) as a staple crop. Except for the actual felling of new gardens, women are responsible for most of the horticultural work and food preparation. Time budgets were assessed using 24-hour activity diaries. Rates of energy expenditure in typical activities were measured by indirect calorimetry using a Max-Planck respirometer. Daily energy expenditure was calculated using these rates in conjunction with the activity diaries. Rates of energy expenditure in standard activities were moderate and broadly comparable to published values for other populations living in tropical environments. The mean daily energy expenditure was 2,133 kcal (8.9 MJ). This value is similar to that reported for other subsistence horticulturalists and close to the FAO recommendation for energy intake for moderately active individuals. PMID:6496659

Dufour, D L

1984-09-01

251

Monosaccharide composition of sweetpotato fiber and cell wall polysaccharides from sweetpotato, cassava, and potato analyzed by the high-performance anion exchange chromatography with pulsed amperometric detection method.  

PubMed

The cell wall materials (CWMs) from sweetpotato (Ipomoea batatas cv. Kokei 14), cassava (Manihot esculenta), and potato (Solanum tuberosum cv. Danshaku) and commercial sweetpotato fiber as well as their polysaccharide fractions were analyzed for sugar composition by the high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) method. The separation of arabinose and rhamnose, and xylose and mannose, by this method has been improved using a CarboPac PA 10 column. Pretreatment of the CWMs and cellulose fractions with 12 M H(2)SO(4) was required for complete hydrolysis to occur. Commercial sweetpotato fiber was found to be mainly composed of glucose (88.4%), but small amounts of other sugars were also detected. Among the root crops, sweetpotato CWM had the highest amount of pectin and galacturonic acid. Fucose was detected only in cassava CWM and its hemicellulose fraction, while galactose was present in the highest amount in potato CWM. Among the polysaccharide fractions, it was only in the hemicellulose fraction where significant differences in the sugar composition, especially in the galactose content, were observed among the root crops. PMID:10956132

Salvador, L D; Suganuma, T; Kitahara, K; Tanoue, H; Ichiki, M

2000-08-01

252

Determination of cyanide and cyanogenic compounds in biological systems.  

PubMed

A survey of methods for the qualitative and quantitative determination of cyanide and cyanogenic compounds is presented. Particular attention is paid to determination in complex matrices. Chromatographic methods able to separate mixtures of closely related structures, such as glycosides of enantiomeric hydroxynitriles or lipids with slightly differing fatty acid spectra, are included, as are highly selective methods of detection, such as enzymic post-column cleavage combined with electrochemical detection as used in high-performance liquid chromatography. Details of thin-layer chromatography, including methods for detection, are given for both straight-phase and reverse-phase systems. The survey includes simple field methods as well as automated laboratory methods for the determination of 'free', 'bound' and 'total' cyanide, for example in processed food products from Manihot esculenta Cranz. Sources of enzymes are listed and attention is given to problems of sample storage and preparation. References are given to review articles which include data from methods such as ultraviolet, infrared and proton and carbon-13 nuclear magnetic resonance spectroscopies. PMID:3073056

Brimer, L

1988-01-01

253

Acromyrmex octospinosus (Hymenoptera: Formicidae) management: effects of TRAMILs fungicidal plant extracts.  

PubMed

Leaf-cutting ants, Acromyrmex octospinosus (Reich), are considering among the most important pest species of the New World. Until now, the main insecticides used for controlling these ants were synthetic chemicals. Leaf-cutting ants live in obligate symbiosis with abasidiomycete fungus, Leucocoprinus gongylophorus (Heim) Moeller. The crucial role of this symbiotic partner in the nest of leaf-cutting ants has prompted us to focus on A. octospinosus management through the use of fungicides in our study. Five parts of plants identified for their antifungal potential through TRAMIL ethnopharmacological surveys were tested: 1) bulbs of Allium cepa L.; 2) seed pods of Allium sativum L.; 3) green fruits of Lycopersicon esculentum L.; 4) leaves of Manihot esculenta Crantz; and 5) leaves of Senna alata (L.) Roxburgh. One plant extract with strong fungicidal activity (S. alata) against L. gongylophorus was found. The other extracts had lesser fungistatic or fungicidal effects depending on the concentrations used. The data presented in this study showed that TRAMILs fungicidal plant extracts have potential to control the symbiotic fungus of leaf cutting ants, in particular a foliage extract of S. alata. PMID:22928301

Boulogne, Isabelle; Ozier-Lafontaine, Harry; Germosén-Robineau, Lionel; Desfontaines, Lucienne; Loranger-Merciris, Gladys

2012-08-01

254

Tuber storage proteins.  

PubMed

A wide range of plants are grown for their edible tubers, but five species together account for almost 90 % of the total world production. These are potato (Solanum tuberosum), cassava (Manihot esculenta), sweet potato (Ipomoea batatus), yams (Dioscorea spp.) and taro (Colocasia, Cyrtosperma and Xanthosoma spp.). All of these, except cassava, contain groups of storage proteins, but these differ in the biological properties and evolutionary relationships. Thus, patatin from potato exhibits activity as an acylhydrolase and esterase, sporamin from sweet potato is an inhibitor of trypsin, and dioscorin from yam is a carbonic anhydrase. Both sporamin and dioscorin also exhibit antioxidant and radical scavenging activity. Taro differs from the other three crops in that it contains two major types of storage protein: a trypsin inhibitor related to sporamin and a mannose-binding lectin. These characteristics indicate that tuber storage proteins have evolved independently in different species, which contrasts with the highly conserved families of storage proteins present in seeds. Furthermore, all exhibit biological activities which could contribute to resistance to pests, pathogens or abiotic stresses, indicating that they may have dual roles in the tubers. PMID:12730067

Shewry, Peter R

2003-04-09

255

Nutrient content of young cassava leaves and assessment of their acceptance as a green vegetable in Nigeria.  

PubMed

Cassava (Manihot esculenta Crantz) leaves contained a high level of crude protein (29.3-32.4% dry weight) compared to a conventional vegetable, Amaranthus (19.6%). Ash was 4.6-6.4% in cassava leaf samples but 13.1% dry weight in Amaranthus. Dietary fibre was very high in all samples (26.9-39% dry weight) while HCN-potential was low (5.1-12.6 mg/100 g dry weight). Tannin was the highest in IITA red cassava leaves (29.7 mg/g) and the lowest in Amaranthus vegetable. In vitro digestibility was very low in oven dried samples (15.6-22.7%). Blanching increased protein content (except Amaranthus) and in vitro protein digestibility but decreased ash, minerals, dietary fibre and tannin, while HCN-potential was unchanged. Grinding reduced both HCN-potential and tannin by 84 and 71% respectively while oven drying only reduced the HCN content marginally. Preference studies showed that the highest percentage of respondents (25.3%) preferred Amaranthus vegetable, followed by Celosia (17.5%), Talinum (12.4%), garden egg (11.5%), with cassava leaves as the least (0.5%). Organoleptic evaluation rated cassava leaf soup inferior to Amaranthus in terms of appearance, colour and texture but equal in terms of taste and flavour and overall acceptability. PMID:7784394

Awoyinka, A F; Abegunde, V O; Adewusi, S R

1995-01-01

256

RNAi-mediated resistance to Cassava brown streak Uganda virus in transgenic cassava.  

PubMed

Cassava brown streak disease (CBSD), caused by Cassava brown streak Uganda virus (CBSUV) and Cassava brown streak virus (CBSV), is of new epidemic importance to cassava (Manihot esculenta Crantz) production in East Africa, and an emerging threat to the crop in Central and West Africa. This study demonstrates that at least one of these two ipomoviruses, CBSUV, can be efficiently controlled using RNA interference (RNAi) technology in cassava. An RNAi construct targeting the near full-length coat protein (FL-CP) of CBSUV was expressed constitutively as a hairpin construct in cassava. Transgenic cassava lines expressing small interfering RNAs (siRNAs) against this sequence showed 100% resistance to CBSUV across replicated graft inoculation experiments. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed the presence of CBSUV in leaves and some tuberous roots from challenged controls, but not in the same tissues from transgenic plants. This is the first demonstration of RNAi-mediated resistance to the ipomovirus CBSUV in cassava. PMID:21726367

Yadav, Jitender S; Ogwok, Emmanuel; Wagaba, Henry; Patil, Basavaprabhu L; Bagewadi, Basavaraj; Alicai, Titus; Gaitan-Solis, Eliana; Taylor, Nigel J; Fauquet, Claude M

2011-02-17

257

Transmission studies with Cassava brown streak Uganda virus (Potyviridae: Ipomovirus) and its interaction with abiotic and biotic factors in Nicotiana benthamiana.  

PubMed

Cassava brown streak disease (CBSD), caused by two distinct species, Cassava brown streak Uganda virus (CBSUV) and Cassava brown streak virus (CBSV), is a major constraint to cassava (Manihot esculenta Crantz) production in Africa. Absence of infectious clones of CBSUV or CBSV and the lack of efficient means of mechanical transmission of CBSD has hampered laboratory studies of this disease. Mechanical transmission, achieved mainly by plant sap inoculation, is a widely used technique for characterizing plant viruses. Efficient sap transmission of CBSUV/CBSV to the common laboratory host Nicotiana benthamiana is essential for both basic and applied studies of the virus. We report here the development of an efficient protocol for sap transmission of CBSUV to N. benthamiana and N. debneyi. Several factors affecting transmission efficiency were identified such as the effects of buffer composition, antioxidants, inoculum concentration, plant age and temperature. Higher temperatures (30 °C) favored rapid symptom initiation compared to lower temperatures (21 °C) when sap prepared in phosphate buffer of pH 7.0 was applied on the leaves of N. benthamiana dusted with the abrasive (carborundum). We demonstrated the usefulness of the transmission method in transient evaluation of CBSUV[UG:Nam:04]-derived RNA interference constructs for CBSD resistance and also in studying the interaction of CBSUV[UG:Nam:04] with cassava mosaic geminiviruses, another important group of viruses infecting cassava. PMID:20691215

Ogwok, Emmanuel; Patil, Basavaprabhu L; Alicai, Titus; Fauquet, Claude M

2010-08-04

258

Whole-Plant Water use and Canopy Conductance of Cassava Under Iimited Available Soil Water and Varying Evaporative Demand  

Microsoft Academic Search

Cassava (Manihot esculenta Crantz), a perennial woody shrub, is known to be highly productive under favourable conditions and produce reasonably well\\u000a under adverse conditions where other crops fail. Using constant heat sap flow sensors, sap flow density (F\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009d\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009) of cassava was monitored for 10 days in December 2002. Sap flow was highly correlated (R\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u00092\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009=0.72, PR\\u000a \\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009\\u0009s) than

Philip G. Oguntunde

2005-01-01

259

Cassava: a basic energy source in the tropics  

SciTech Connect

Cassava (Manihot esculenta) is the fourth most important source of food energy in the tropics. More than two-thirds of the total production of this crop is used as food for humans, with lesser amounts being used for animal feed and industrial purposes. The ingestion of high levels of cassava has been associated with chronic cyanide toxicity in parts of Africa, but this appears to be related to inadequate processing of the root and poor overall nutrition. Although cassava is not a complete food it is important as a cheap source of calories. The crop has a high yield potential under good conditions, and compared to other crops it excels under suboptimal conditions, thus offering the possibility of using marginal land to increase total agricultural production. Breeding programs that bring together germ plasm from different regions coupled with improved agronomic practices can markedly increase yields. The future demand for fresh cassava may depend on improved storage methods. The markets for cassava as a substitute for cereal flours in bakery products and as an energy source in animal feed rations are likely to expand. The use of cassava as a source of ethanol for fuel depends on finding an efficient source of energy for distillation or an improved method of separating ethanol from water. 7 figures, 8 tables.

Cock, J.H.

1982-11-19

260

Moisture-pressure combination treatments for cyanide reduction in grated cassava.  

PubMed

Several cyanide-associated health disorders have been linked with frequent consumption of mildly toxic cassava (Manihot esculenta crantz) products in individuals on a low-protein diet. Production of bread from cassava often involves application of prolonged physical pressure (pressing) to the freshly grated root for several hours. This study aimed to determine effects of pressure and wetting on grated cassava. Six treatments were applied: confining pressure for 12 h, wetting for 4 h at 25 °C, 2 h at 25 °C, 2 h at 40 °C, and 2 h at 50 °C, or each of the above followed by pressure for 12 h. Treatments released cyanide from samples in the order: 2-h wet at 50 °C + pressing >4-h wet at 25 °C + pressing = 2-h wet at 40 °C + pressing >2-h wet at 25 °C + pressing = 4-h wet at 25 °C >12-h pressing. Wetting for 2 h at 50 °C followed by pressure for 12 h reduced cyanide levels by at least 20% more than that of any other treatment. The combination of moisture and pressure enhanced the contact time between linamarin and linamarase to increase the release of hydrogen cyanide. PMID:21535726

Harris, Mark Anglin; Koomson, Charles Kofi

2011-01-06

261

Production and characterization of a plant alpha-hydroxynitrile lyase in Escherichia coli.  

PubMed

The coding sequence of the cyanogenic alpha-hydroxynitrile lyase gene of Manihot esculenta Crantz (cassava) was cloned in the plasmid vector pMal-c2 and expressed in Escherichia coli strain JM105. DNA sequencing showed that the recombinant plasmid contained the same sequence as the cDNA clone pHNL10. Peptide sequencing of the recombinant protein showed that the N-terminus was heterogeneous, with either four or six additional amino acid residues compared with the native protein. Circular dichroism spectra indicated similar secondary structure contents for both proteins. Enzyme assays showed that specific activity of native and recombinant proteins were 0.24 and 0.26 mmol CN(-)/mg/min, respectively; that both proteins had optimal activity at 40 degrees C and pH 5.5; and that both proteins were inhibited by the serine protease inhibitor phenyl-methane sulfonyl flouride (PMSF). Isoelectric focusing of native and recombinant protein revealed multiple isoforms for both proteins; the recombinant protein had a more basic mean isoelectric point (pl) (5.1) than the native protein (4.5). PMID:18633988

Hughes, J; Lakey, J H; Hughes, M A

1997-02-01

262

Cassava starch as a stabilizer of soy-based beverages.  

PubMed

Soy-based beverages are presented as healthy food alternatives for human nutrition. Cassava (Manihot esculenta, Crantz) starch is relatively inexpensive, widely available in Brazil and is broadly used by the food industry due to its desired properties that result from pasting. The objective of this study was to develop soy-based beverages with good sensory quality using native cassava starch as a stabilizer and maintaining the nutritional value that makes this product a functional food. The developed formulations featured a range of cassava starch and soybean extract concentrations, which were tested in a 2² experimental design with three central points. The results of sensory analysis showed that the studied variables (cassava starch and soybean extract concentrations) did not have a significant effect with respect to a 5% probability level. When considering the apparent viscosity, on the other hand, the variables had a significant effect: the increase in soybean extract and cassava starch concentrations caused an increase in the viscosity of the final product. The profile of isoflavones in the tested formulations was similar to the profiles reported in other papers, with a predominance of the conjugated glycosides over the aglycone forms. PMID:23144242

Drunkler, Northon Lee; Leite, Rodrigo Santos; Mandarino, José Marcos Gontijo; Ida, Elza Iouko; Demiate, Ivo Mottin

2012-10-01

263

Relative contribution of biotic and abiotic factors to the population density of the cassava green mite, Mononychellus tanajoa (Acari: Tetranychidae).  

PubMed

The cassava green mite, Mononychellus tanajoa, is a key pest of cassava, Manihot esculenta Crantz (Euphorbiaceae), and it may be kept in check by naturally occurring predatory mites of the family Phytoseiidae. In addition to predatory mites, abiotic factors may also contribute to regulate pest mite populations in the field. Here, we evaluated the population densities of both M. tanajoa and the generalist predatory mite Euseius ho DeLeon (Acari: Phytoseiidae) over the cultivation cycle (11 months) of cassava in four study sites located around the city of Miranda do Norte, Maranhão, Brazil. The abiotic variables rainfall, temperature and relative humidity were also recorded throughout the cultivation cycle of cassava. We determined the relative importance of biotic (density of E. ho) and abiotic (rainfall, temperature and relative humidity) factors to the density of M. tanajoa. The density of M. tanajoa increased whereas the density of E. ho remained constant throughout time. A hierarchical partitioning analysis revealed that most of the variance for the density of M. tanajoa was explained by rainfall and relative humidity followed by E. ho density and temperature. We conclude that abiotic factors, especially rainfall, were the main mechanisms driving M. tanajoa densities. PMID:23417702

Rêgo, Adriano S; Teodoro, Adenir V; Maciel, Anilde G S; Sarmento, Renato A

2013-02-17

264

Determination of the specific growth of molds on semi-solid cultures  

SciTech Connect

The determination of growth constants of Aspergillus niger were obtained for semisolid cultures on cassava flour, Manihot esculenta, as a sole carbon source. As a consequence, a technique was developed that consisted of the use of a packed-bed microfermentor with a working volume of 16 cubic centimetres. The bed consisted of gelatinized and granulated cassava flour containing material nutrients and mold spores. The carbon dioxide produced during the respiration was drawn off with a current of air and then absorbed in a solution of sodium hydroxide. The absorption of CO/sub 2/, P, was correlated with the specific growth rate mu by means of the equation P equals Kemut, where t is time and K is a constant. Ammonium nitrogen was used as a limiting substrate and its concentration was varied from 0.039 to 2.5% in dry base. The maximum growth rate, mu maximum, and the saturation constant, Ks, were 0.31/hour and 0.065 mmol (N/sub 4/)/sub 2/SO/sub 4//g total dry solids. The proposed method is highly recommended for the evaluation of the semisolid fermentation of molds and for strictly aerobic bacteria and yeasts. It can be used especially in the evaluation of the growth of microorganisms on peanut shells, coffee residues, sugar cane bagasse, and other agricultural wastes.

Carrizalez, V.; Rodriguez, H.; Sardina, I.

1981-02-01

265

Genome-wide discovery and information resource development of DNA polymorphisms in cassava.  

PubMed

Cassava (Manihot esculenta Crantz) is an important crop that provides food security and income generation in many tropical countries, and is known for its adaptability to various environmental conditions. Its draft genome sequence and many expressed sequence tags are now publicly available, allowing the development of cassava polymorphism information. Here, we describe the genome-wide discovery of cassava DNA polymorphisms. Using the alignment of predicted transcribed sequences from the cassava draft genome sequence and ESTs from GenBank, we discovered 10,546 single-nucleotide polymorphisms and 647 insertions and deletions. To facilitate molecular marker development for cassava, we designed 9,316 PCR primer pairs to amplify the genomic region around each DNA polymorphism. Of the discovered SNPs, 62.7% occurred in protein-coding regions. Disease-resistance genes were found to have a significantly higher ratio of nonsynonymous-to-synonymous substitutions. We identified 24 read-through (changes of a stop codon to a coding codon) and 38 premature stop (changes of a coding codon to a stop codon) single-nucleotide polymorphisms, and found that the 5 gene ontology terms in biological process were significantly different in genes with read-through single-nucleotide polymorphisms compared with all cassava genes. All data on the discovered DNA polymorphisms were organized into the Cassava Online Archive database, which is available at http://cassava.psc.riken.jp/. PMID:24040164

Sakurai, Tetsuya; Mochida, Keiichi; Yoshida, Takuhiro; Akiyama, Kenji; Ishitani, Manabu; Seki, Motoaki; Shinozaki, Kazuo

2013-09-11

266

Characterization of kappa 1 and kappa 2 opioid binding sites in frog (Rana esculenta) brain membrane preparation  

SciTech Connect

The distribution and properties of frog brain kappa-opioid receptor subtypes differ not only from those of the guinea pig brain, but also from that of the rat brain. In guinea pig cerebellum the kappa 1 is the dominant receptor subtype, frog brain contains mainly the kappa 2 subtype, and the distribution of the rat brain subtypes is intermediate between the two others. In competition experiments it has been established that ethylketocyclazocine and N-cyclopropylmethyl-norazidomorphine, which are nonselective kappa-ligands, have relatively high affinities to frog brain membranes. The kappa 2 ligands (Met5)enkephalin-Arg6-Phe7 and etorphine also show high affinities to the frog brain. Kappa 1 binding sites measured in the presence of 5 microM/D-Ala2-Leu5/enkephalin represent 25-30% of (3H)ethylketocyclazocine binding in frog brain membranes. The kappa 2 subtype in frog brain resembles more to the mu subtype than the delta subtype of opioid receptors, but it differs from the mu subtype in displaying low affinity toward beta-endorphin and /D-Ala2-(Me)Phe4-Gly5-ol/enkephalin (DAGO). From our data it is evident that the opioid receptor subtypes are already present in the amphibian brain but the differences among them are less pronounced than in mammalian brain.

Benyhe, S.; Varga, E.; Hepp, J.; Magyar, A.; Borsodi, A.; Wollemann, M.

1990-09-01

267

Inhibitory effect of onion extract on polyphenol oxidase and enzymatic browning of taro ( Colocasia antiquorum var. esculenta)  

Microsoft Academic Search

The inhibitory effect of onion extract on polyphenol oxidase and enzymatic browning of taro was investigated. The polyphenol oxidase from taro was strongly inhibited by various reducing agents, such as l-ascorbic acid, l-cysteine, dithiothreitol, glutathione and sodium pyrosulfite. The enzyme was also inhibited by addition of onion extract. Regardless of substrates used, the addition of heated onion extract at 100°C

Min Young Lee; Min Kyung Lee

2007-01-01

268

The edible brown seaweed Alaria esculenta (Phaeophyceae, Laminariales): hybridization, growth and genetic comparisons of six Irish populations  

Microsoft Academic Search

Alaria esculentapopulations from six different geographical locations on the Irish coast were examined for hybrid- ization abilities, growth rates and genetic make-up with a view towards identifying a fast-growing strain suitable for aquaculture. Hybridization experiments under laboratory conditions with the three most geographically dispersed populations showed that all cross combinations were interfertile, although differences were found in survival, and in

Stefan Kraan; Adriana Verges Tramullas; Michael D. Guiry

2000-01-01

269

Characterization of kappa 1 and kappa 2 opioid binding sites in frog (rana esculenta) brain membrane preparation  

Microsoft Academic Search

The distribution and properties of frog brain kappa-opioid receptor subtypes differ not only from those of the guinea pig brain, but also from that of the rat brain. In guinea pig cerebellum the kappa1 is the dominat receptor subtype, frog brain contains mainly the kappa2 subtype, and the distribution of the rat brain subtypes is intermediate between the two others.

Sandor Benyhe; Eva Varga; Jozsef Hepp; Anna Magyar; Anna Borsodi; Maria Wollemann

1990-01-01

270

A close phylogenetic relationship between Sipuncula and Annelida evidenced from the complete mitochondrial genome sequence of Phascolosoma esculenta  

Microsoft Academic Search

BACKGROUND: There are many advantages to the application of complete mitochondrial (mt) genomes in the accurate reconstruction of phylogenetic relationships in Metazoa. Although over one thousand metazoan genomes have been sequenced, the taxonomic sampling is highly biased, left with many phyla without a single representative of complete mitochondrial genome. Sipuncula (peanut worms or star worms) is a small taxon of

Xin Shen; Xiaoyin Ma; Jianfeng Ren; Fangqing Zhao

2009-01-01

271

Aural Myiasis in Children and Literature Review  

Microsoft Academic Search

YUCA, K., ÇAKSEN, H., SAKIN, Y.F., YUCA, S.A., KIRIS ¸, M., YILMAZ, H. and ÇANKAYA, H. Aural Myiasis in Children and Literature Review. Tohoku J. Exp. Med., 2005, 206 (2), 125-130 ?? Myiasis is a disease caused by fly larvae. The term \\

Köksal Yuca; Hüseyin Çaksen; Yunus Feyyat Sakin; Sevil Ari Yuca; Muzaffer Kiris; Hasan Yilmaz; Hakan Çankaya

2005-01-01

272

Extending cassava root shelf life via reduction of reactive oxygen species production.  

PubMed

One of the major constraints facing the large-scale production of cassava (Manihot esculenta) roots is the rapid postharvest physiological deterioration (PPD) that occurs within 72 h following harvest. One of the earliest recognized biochemical events during the initiation of PPD is a rapid burst of reactive oxygen species (ROS) accumulation. We have investigated the source of this oxidative burst to identify possible strategies to limit its extent and to extend cassava root shelf life. We provide evidence for a causal link between cyanogenesis and the onset of the oxidative burst that triggers PPD. By measuring ROS accumulation in transgenic low-cyanogen plants with and without cyanide complementation, we show that PPD is cyanide dependent, presumably resulting from a cyanide-dependent inhibition of respiration. To reduce cyanide-dependent ROS production in cassava root mitochondria, we generated transgenic plants expressing a codon-optimized Arabidopsis (Arabidopsis thaliana) mitochondrial alternative oxidase gene (AOX1A). Unlike cytochrome c oxidase, AOX is cyanide insensitive. Transgenic plants overexpressing AOX exhibited over a 10-fold reduction in ROS accumulation compared with wild-type plants. The reduction in ROS accumulation was associated with a delayed onset of PPD by 14 to 21 d after harvest of greenhouse-grown plants. The delay in PPD in transgenic plants was also observed under field conditions, but with a root biomass yield loss in the highest AOX-expressing lines. These data reveal a mechanism for PPD in cassava based on cyanide-induced oxidative stress as well as PPD control strategies involving inhibition of ROS production or its sequestration. PMID:22711743

Zidenga, Tawanda; Leyva-Guerrero, Elisa; Moon, Hangsik; Siritunga, Dimuth; Sayre, Richard

2012-06-18

273

Anopheles gambiae feeding and survival on honeydew and extra-floral nectar of peridomestic plants.  

PubMed

It is widely believed that the malaria vector Anopheles gambiae Giles (Diptera: Culicidae) rarely or never feeds on sugar in nature. If so, the need for supplemental blood-feeding may be increased and this would help to explain why it is such an efficient malaria vector. Nonetheless, both sexes of this mosquito species readily imbibe and digest sugar solutions, and sugar is a staple of laboratory colonies. In this study, we investigated whether An. gambiae will feed on the extra-floral nectar of three common peridomestic plants in Africa, and on honeydew of the mealybug Pseudococcus longispinus (Targioni-Tozetti) (Hemiptera: Homoptera: Pseudococcidae), and how this affects survivorship. We found that both males and females of An. gambiae provided with vegetative parts of cassava (Manihot esculenta Crantz) survived as well (x = 26.3 and 19.2 days, respectively) as they did on 50% sucrose solution (x = 29.7 and 24.3 days, respectively) and much longer than they did on water alone (x = 1.8 days, both sexes). Females provided with mealybug honeydew also lived substantially longer (x = 16.5 days) than those on water alone. Males and females provided with vegetative parts of castorbean (Ricinus communis L.) also survived much longer (x = 12.7 and 7.8 days, respectively) than on water, but those provided with flowering lantana (Lantana camara L.) did not. Anthrone tests of females after one night of exposure to these potential energy sources confirmed that they obtained fructose from cassava, from mealybug honeydew, and from non-flowering castorbean, but not from lantana or from castorbean lacking its petiolar nectaries. Previous laboratory studies had shown that sugar availability affects the survival and biting frequency of An. gambiae. It now appears that this mosquito can locate natural sources of plant sugar readily and utilize them effectively. Nectar-producing plants in the domestic environment may play a significant role in this mosquito's energy budget and malaria vectorial capacity. PMID:15189234

Gary, R E; Foster, W A

2004-06-01

274

Conversion of Sterically Demanding ?,?-Disubstituted Phenylacetonitriles by the Arylacetonitrilase from Pseudomonas fluorescens EBC191  

PubMed Central

The nitrilase from Pseudomonas fluorescens EBC191 converted 2-methyl-2-phenylpropionitrile, which contains a quaternary carbon atom in the ?-position toward the nitrile group, and also similar sterically demanding substrates, such as 2-hydroxy-2-phenylpropionitrile (acetophenone cyanohydrin) or 2-acetyloxy-2-methylphenylacetonitrile. 2-Methyl-2-phenylpropionitrile was hydrolyzed to almost stoichiometric amounts of the corresponding acid. Acetophenone cyanohydrin was transformed to the corresponding acid (atrolactate) and amide (atrolactamide) at a ratio of about 3.4:1. The (R)-acid and the (S)-amide were formed preferentially from acetophenone cyanohydrin. A homology model of the nitrilase suggested that steric hindrance with amino acid residue Tyr54 could impair the binding or conversion of sterically demanding substrates. Therefore, several enzyme variants that carried mutations in the respective residues were generated and subsequently analyzed for the substrate specificity and enantioselectivity of the reactions. Enzyme variants that demonstrated increased relative activities for the conversion of acetophenone cyanohydrin were identified. The chiral analysis of these reactions demonstrated peculiar reaction kinetics, which suggested that the enzyme variants converted the nonpreferred (S)-enantiomer of acetophenone cyanohydrin with a higher reaction rate than that of the (preferred) (R)-enantiomer. Recombinant whole-cell catalysts that simultaneously produced the nitrilase from P. fluorescens EBC191 and a plant-derived (S)-oxynitrilase from cassava (Manihot esculenta) converted acetophenone plus cyanide at pH 4.5 to (S)-atrolactate and (S)-atrolactamide. These recombinant cells are promising catalysts for the synthesis of stable chiral quaternary carbon centers from ketones.

Baum, Stefanie; Williamson, Dael S.; Sewell, Trevor

2012-01-01

275

Introduction of East African cassava mosaic Zanzibar virus to Oman harks back to "Zanzibar, the capital of Oman".  

PubMed

Cassava mosaic disease (CMD) is the most devastating disease of the subsistence crop cassava (Manihot esculenta) across Africa and the Indian subcontinent. The disease is caused by viruses of the genus Begomovirus (family Geminiviridae)-seven species have been identified so far. The Sultanate of Oman is unusual among countries in Arabia in growing cassava on a small scale for local consumption. During a recent survey in A'Seeb wilayat of Muscat governorate, Oman, cassava plants were identified with symptoms typical of CMD. A begomovirus, East African cassava mosaic Zanzibar virus (EACMZV), was isolated from symptomatic plants. This virus was previously only known to occur in Zanzibar and Kenya. During the 19th Century, Zanzibar was governed by Oman and was so important that the Sultan of Oman moved his capital there from Muscat. After a period of colonial rule, the governing Arab elite was overthrown, following independence in the 1960s, and many expatriate Omanis returned to their homeland. Having gained a liking for the local Zanzibar cuisine, it appears that returning Omanis did not wish to do without dishes made from one particular favorite, cassava. Consequently, they carried planting material back to Oman for cultivation in their kitchen gardens. The evidence suggests that this material harbored EACMZV. Recently, Oman has been shown to be a nexus for geminiviruses and their associated satellites from diverse geographic origins. With their propensity to recombine, a major mechanism for evolution of geminiviruses, and the fact that Oman (and several other Arabian countries) is a major hub for trade and travel by air and sea, the possibility of onward spread is worrying. PMID:23085885

Khan, Akhtar J; Akhtar, Sohail; Al-Matrushi, Abdulrahman M; Fauquet, Claude M; Briddon, Rob W

2012-10-20

276

Biofortification of essential nutritional compounds and trace elements in rice and cassava.  

PubMed

Plant biotechnology can make important contributions to food security and nutritional improvement. For example, the development of 'Golden Rice' by Professor Ingo Potrykus was a milestone in the application of gene technology to deliver both increased nutritional qualities and health improvement to wide sections of the human population. Mineral nutrient and protein deficiency as well as food security remain the most important challenges for developing countries. Current projects are addressing these issues in two major staple crops, cassava (Manihot esculenta Crantz) and rice. The tropical root crop cassava is a major source of food for approximately 600 million of the population worldwide. In sub-Saharan Africa >200 million of the population rely on cassava as their major source of dietary energy. The nutritional quality of the cassava root is not sufficient to meet all dietary needs. Rice is the staple food for half the world population, providing approximately 20% of the per capita energy and 13% of the protein for human consumption worldwide. In many developing countries the dietary contributions of rice are substantially greater (29.3% dietary energy and 29.1% dietary protein). The current six most popular 'mega' rice varieties (in terms of popularity and acreage), including Chinese hybrid rice, have an incomplete amino acid profile and contain limited amounts of essential micronutrients. Rice lines with improved Fe contents have been developed using genes that have functions in Fe absorption, translocation and accumulation in the plant, as well as improved Fe bioavailability in the human intestine. Current developments in biotechnology-assisted plant improvement are reviewed and the potential of the technology in addressing human nutrition and health are discussed. PMID:16672076

Sautter, C; Poletti, S; Zhang, P; Gruissem, W

2006-05-01

277

Conservation and divergence of microRNAs and their functions in Euphorbiaceous plants  

PubMed Central

MicroRNAs (miRNAs) are ?21 nt non-coding RNAs which regulate post-transcriptional gene expression. miRNAs are key regulators of nearly all essential biological processes. Aiming at understanding miRNA’s functions in Euphorbiaceae, a large flowering plant family, we performed a genome-scale systematic study of miRNAs in Euphorbiaceae, by combining computational prediction and experimental analysis to overcome the difficulty of lack of genomes for most Euphorbiaceous species. Specifically, we predicted 85 conserved miRNAs in 23 families in the Castor bean (Ricinus communis), and experimentally verified and characterized 58 (68.2%) of the 85 miRNAs in at least one of four Euphorbiaceous species, the Castor bean, the Cassava (Manihot esculenta), the Rubber tree (Hevea brasiliensis) and the Jatropha (Jatropha curcas) during normal seedling development. To elucidate their function in stress response, we verified and profiled 48 (56.5%) of the 85 miRNAs under cold and drought stresses as well as during the processes of stress recovery. The results revealed some species- and condition-specific miRNA expression patterns. Finally, we predicted 258 miRNA:target partners, and identified the cleavage sites of six out of ten miRNA targets by a modified 5? RACE. This study produced the first collection of miRNAs and their targets in Euphorbiaceae. Our results revealed wide conservation of many miRNAs and diverse functions in Euphorbiaceous plants during seedling growth and in response to abiotic stresses.

Zeng, Changying; Wang, Wenquan; Zheng, Yun; Chen, Xin; Bo, Weiping; Song, Shun; Zhang, Weixiong; Peng, Ming

2010-01-01

278

Informal "Seed" Systems and the Management of Gene Flow in Traditional Agroecosystems: The Case of Cassava in Cauca, Colombia  

PubMed Central

Our ability to manage gene flow within traditional agroecosystems and their repercussions requires understanding the biology of crops, including farming practices' role in crop ecology. That these practices' effects on crop population genetics have not been quantified bespeaks lack of an appropriate analytical framework. We use a model that construes seed-management practices as part of a crop's demography to describe the dynamics of cassava (Manihot esculenta Crantz) in Cauca, Colombia. We quantify several management practices for cassava—the first estimates of their kind for a vegetatively-propagated crop—describe their demographic repercussions, and compare them to those of maize, a sexually-reproduced grain crop. We discuss the implications for gene flow, the conservation of cassava diversity, and the biosafety of vegetatively-propagated crops in centers of diversity. Cassava populations are surprisingly open and dynamic: farmers exchange germplasm across localities, particularly improved varieties, and distribute it among neighbors at extremely high rates vis-à-vis maize. This implies that a large portion of cassava populations consists of non-local germplasm, often grown in mixed stands with local varieties. Gene flow from this germplasm into local seed banks and gene pools via pollen has been documented, but its extent remains uncertain. In sum, cassava's biology and vegetative propagation might facilitate pre-release confinement of genetically-modified varieties, as expected, but simultaneously contribute to their diffusion across traditional agroecosystems if released. Genetically-modified cassava is unlikely to displace landraces or compromise their diversity; but rapid diffusion of improved germplasm and subsequent incorporation into cassava landraces, seed banks or wild populations could obstruct the tracking and eradication of deleterious transgenes. Attempts to regulate traditional farming practices to reduce the risks could compromise cassava populations' adaptive potential and ultimately prove ineffectual.

Dyer, George A.; Gonzalez, Carolina; Lopera, Diana Carolina

2011-01-01

279

Cassava For Space Diet  

NASA Astrophysics Data System (ADS)

Space agriculture is an advanced life support enginnering concept based on biological and ecological system ot drive the materials recycle loop and create pleasant life environment on distant planetary bodies. Choice of space diet is one of primary decision required ot be made at designing space agriculture. We propose cassava, Manihot esculenta and, for one major composition of space food materials, and evaluate its value and feasibility of farming and processing it for space diet. Criteria to select space crop species could be stated as follows. 1) Fill th enutritional requirements. There is no perfect food material to meet this requirements without making a combination with others. A set of food materials which are adopted inthe space recipe shall fit to the nutritional requirement. 2) Space food is not just for maintaining physiological activities of human, but an element of human culture. We shall consider joy of dining in space life. In this context, space foos or recipe should be accepted by future astronauts. Food culture is diverse in the world, and has close relatioship to each cultural background. Cassava root tuber is a material to supply mainly energy in the form of carbohydrate, same as cereals and other tuber crops. Cassava leaf is rich in protein high as 5.1 percents about ten times higher content than its tuber. In the food culture in Africa, cassava is a major component. Cassava root tuber in most of its strain contains cyanide, it should be removed during preparation for cooking. However certain strain are less in this cyanogenic compound, and genetically modified cassava can also aboid this problem safely.

Katayama, Naomi; Yamashita, Masamichi; Njemanze, Philip; Nweke, Felix; Mitsuhashi, Jun; Hachiya, Natumi; Miyashita, Sachiko; Hotta, Atuko

280

Bioinformatic identification of cassava miRNAs differentially expressed in response to infection by Xanthomonas axonopodis pv. manihotis  

PubMed Central

Background microRNAs (miRNAs) are short RNA molecules that control gene expression by silencing complementary mRNA. They play a crucial role in stress response in plants, including biotic stress. Some miRNAs are known to respond to bacterial infection in Arabidopsis thaliana but it is currently unknown whether these responses are conserved in other plants and whether novel species-specific miRNAs could have a role in defense. Results This work addresses the role of miRNAs in the Manihot esculenta (cassava)-Xanthomonas axonopodis pv. manihotis (Xam) interaction. Next-generation sequencing was used for analyzing small RNA libraries from cassava tissue infected and non-infected with Xam. A full repertoire of cassava miRNAs was characterized, which included 56 conserved families and 12 novel cassava-specific families. Endogenous targets were predicted in the cassava genome for many miRNA families. Some miRNA families' expression was increased in response to bacterial infection, including miRNAs known to mediate defense by targeting auxin-responding factors as well as some cassava-specific miRNAs. Some bacteria-repressed miRNAs included families involved in copper regulation as well as families targeting disease resistance genes. Putative transcription factor binding sites (TFBS) were identified in the MIRNA genes promoter region and compared to promoter regions in miRNA target genes and protein coding genes, revealing differences between MIRNA gene transcriptional regulation and other genes. Conclusions Taken together these results suggest that miRNAs in cassava play a role in defense against Xam, and that the mechanism is similar to what's known in Arabidopsis and involves some of the same families.

2012-01-01

281

Putative storage root specific promoters from cassava and yam: cloning and evaluation in transgenic carrots as a model system.  

PubMed

A prerequisite for biotechnological improvements of storage roots is the availability of tissue-specific promoters enabling high expression of transgenes. In this work, we cloned two genomic fragments, pMe1 and pDJ3S, controlling the expression of a gene with unknown function from cassava (Manihot esculenta) and of the storage protein dioscorin 3 small subunit gene from yam (Dioscorea japonica), respectively. Using beta-glucuronidase as a reporter, the activities of pMe1 and pDJ3S were evaluated in independent transgenic carrot lines and compared to the constitutive CaMV35S and the previously described cassava p15 promoters. Activities of pMe1 and pDJ3S in storage roots were assessed using quantitative GUS assays that showed pDJ3S as the most active one. To determine organ specificities, uidA transcript levels in leaves, stems and roots were measured by real-time RT-PCR analyses showing highest storage root specificity for pDJ3S. Root cross sections revealed that pMe1 was highly active in secondary xylem. In contrast, pDJ3S was active in all root tissues except for the central xylem. The expression patterns caused by the cassava p15 promoter in carrot storage roots were consistent with its previously described activities for the original storage organ. Our data demonstrate that the pDJ3S and, to a lesser extent, the pMe1 regulatory sequences represent feasible candidates to drive high and preferential expression of genes in carrot storage roots. PMID:20369359

Arango, Jacobo; Salazar, Bertha; Welsch, Ralf; Sarmiento, Felipe; Beyer, Peter; Al-Babili, Salim

2010-04-06

282

Cassava Plants with a Depleted Cyanogenic Glucoside Content in Leaves and Tubers. Distribution of Cyanogenic Glucosides, Their Site of Synthesis and Transport, and Blockage of the Biosynthesis by RNA Interference Technology1  

PubMed Central

Transgenic cassava (Manihot esculenta Crantz, cv MCol22) plants with a 92% reduction in cyanogenic glucoside content in tubers and acyanogenic (<1% of wild type) leaves were obtained by RNA interference to block expression of CYP79D1 and CYP79D2, the two paralogous genes encoding the first committed enzymes in linamarin and lotaustralin synthesis. About 180 independent lines with acyanogenic (<1% of wild type) leaves were obtained. Only a few of these were depleted with respect to cyanogenic glucoside content in tubers. In agreement with this observation, girdling experiments demonstrated that cyanogenic glucosides are synthesized in the shoot apex and transported to the root, resulting in a negative concentration gradient basipetal in the plant with the concentration of cyanogenic glucosides being highest in the shoot apex and the petiole of the first unfolded leaf. Supply of nitrogen increased the cyanogenic glucoside concentration in the shoot apex. In situ polymerase chain reaction studies demonstrated that CYP79D1 and CYP79D2 were preferentially expressed in leaf mesophyll cells positioned adjacent to the epidermis. In young petioles, preferential expression was observed in the epidermis, in the two first cortex cell layers, and in the endodermis together with pericycle cells and specific parenchymatic cells around the laticifers. These data demonstrate that it is possible to drastically reduce the linamarin and lotaustralin content in cassava tubers by blockage of cyanogenic glucoside synthesis in leaves and petioles. The reduced flux to the roots of reduced nitrogen in the form of cyanogenic glucosides did not prevent tuber formation.

J?rgensen, Kirsten; Bak, S?ren; Busk, Peter Kamp; S?rensen, Charlotte; Olsen, Carl Erik; Puonti-Kaerlas, Johanna; M?ller, Birger Lindberg

2005-01-01

283

Effect of soil acidity factors on yields and foliar composition of tropical root crops  

SciTech Connect

Tropical root crops, a major source of food for subsistence farmers, varied in their sensitivity to soil acidity factors. Tolerance to soil acidity is an important characteristic of crops for the humid tropics where soils are often very acid and lime-scarce and expensive. Experiments on two Ultisols and an Oxisol showed that three tropical root crops differed markedly in sensitivity to soil acicity factors. Yams (Dioscorea alata L.) were very sensitive to soil acidity with yields on a Ultisol decreasing from 70% of maximum when Al saturation of the effective cation exchange capacity of the soil was 10 to 25% of maximum when Al saturation was 40%. On the other hand, cassava (Manihot esculenta Crantz) was very tolerant to high levels of soil acidity, yielding about 85% of maximum with 60% Al saturation. Taniers (Xanthosoma sp.) were intermediate between yams and cassava in their tolerance to soil acidity yielding about 60% of maximum with 50% Al saturation of the soil. Foliar composition of cassava was not affected by soil acidity levels and that of yams and taniers was also unaffected except for Ca content which decreased with decreasing soil pH and increasing Al saturation.Response of these tropical root crops to soil acidity components was far more striking on Ultisols than on the Oxisol. For yams, soils should be limed to about pH 5.5 with essentially no exhangeable Al/sup 3 +/ present whereas high yields of taniers can be obtained at about pH 4.8 with 20% exchangeable Al/sup 3 +/ and of cassava at pH as low as 4.5 with 60% exchangeable Al/sup 3 +/.

Abruna-Rodriguez, F.; Vicente-Chandler, J.I. Rivera, E.; Rodriguez, J.

1982-09-01

284

Enhanced reactive oxygen species scavenging by overproduction of superoxide dismutase and catalase delays postharvest physiological deterioration of cassava storage roots.  

PubMed

Postharvest physiological deterioration (PPD) of cassava (Manihot esculenta) storage roots is the result of a rapid oxidative burst, which leads to discoloration of the vascular tissues due to the oxidation of phenolic compounds. In this study, coexpression of the reactive oxygen species (ROS)-scavenging enzymes copper/zinc superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) in transgenic cassava was used to explore the intrinsic relationship between ROS scavenging and PPD occurrence. Transgenic cassava plants integrated with the expression cassette p54::MeCu/ZnSOD-35S::MeCAT1 were confirmed by Southern-blot analysis. The expression of MeCu/ZnSOD and MeCAT1 was verified by quantitative reverse transcription-polymerase chain reaction and enzymatic activity analysis both in the leaves and storage roots. Under exposure to the ROS-generating reagent methyl viologen or to hydrogen peroxide (H2O2), the transgenic plants showed higher enzymatic activities of SOD and CAT than the wild-type plants. Levels of malondialdehyde, chlorophyll degradation, lipid peroxidation, and H2O2 accumulation were dramatically reduced in the transgenic lines compared with the wild type. After harvest, the storage roots of transgenic cassava lines show a delay in their PPD response of at least 10 d, accompanied by less mitochondrial oxidation and H2O2 accumulation, compared with those of the wild type. We hypothesize that this is due to the combined ectopic expression of Cu/ZnSOD and CAT leading to an improved synergistic ROS-scavenging capacity of the roots. Our study not only sheds light on the mechanism of the PPD process but also develops an effective approach for delaying the occurrence of PPD in cassava. PMID:23344905

Xu, Jia; Duan, Xiaoguang; Yang, Jun; Beeching, John R; Zhang, Peng

2013-01-23

285

Visualizing metabolite distribution and enzymatic conversion in plant tissues by desorption electrospray ionization mass spectrometry imaging.  

PubMed

In comparison with the technology platforms developed to localize transcripts and proteins, imaging tools for visualization of metabolite distributions in plant tissues are less well developed and lack versatility. This hampers our understanding of plant metabolism and dynamics. In this study, we demonstrate that desorption electrospray ionization mass spectrometry imaging (DESI-MSI) of tissue imprints on porous Teflon may be used to accurately image the distribution of even labile plant metabolites such as hydroxynitrile glucosides, which normally undergo enzymatic hydrolysis by specific ?-glucosidases upon cell disruption. This fast and simple sample preparation resulted in no substantial differences in the distribution and ratios of all hydroxynitrile glucosides between leaves from wild-type Lotus japonicus and a ?-glucosidase mutant plant that lacks the ability to hydrolyze certain hydroxynitrile glucosides. In wild-type, the enzymatic conversion of hydroxynitrile glucosides and the concomitant release of glucose were easily visualized when a restricted area of the leaf tissue was damaged prior to sample preparation. The gene encoding the first enzyme in hydroxynitrile glucoside biosynthesis in L. japonicus leaves, CYP79D3, was found to be highly expressed during the early stages of leaf development, and the hydroxynitrile glucoside distribution in mature leaves reflected this early expression pattern. The utility of direct DESI-MSI of plant tissue was demonstrated using cryo-sections of cassava (Manihot esculenta) tubers. The hydroxynitrile glucoside levels were highest in the outer cell layers, as verified by LC-MS analyses. The unexpected discovery of a hydroxynitrile-derived di-glycoside shows the potential of DESI-MSI to discover and guide investigations into new metabolic routes. PMID:23551340

Li, Bin; Knudsen, Camilla; Hansen, Natascha Krahl; Jørgensen, Kirsten; Kannangara, Rubini; Bak, Søren; Takos, Adam; Rook, Fred; Hansen, Steen H; Møller, Birger Lindberg; Janfelt, Christian; Bjarnholt, Nanna

2013-05-06

286

Research on motor neuron diseases konzo and neurolathyrism: trends from 1990 to 2010.  

PubMed

Konzo (caused by consumption of improperly processed cassava, Manihot esculenta) and neurolathyrism (caused by prolonged overconsumption of grass pea, Lathyrus sativus) are two distinct non-infectious upper motor neurone diseases with identical clinical symptoms of spastic paraparesis of the legs. They affect many thousands of people among the poor in the remote rural areas in the central and southern parts of Africa afflicting them with konzo in Ethiopia and in the Indian sub-continent with neurolathyrism. Both diseases are toxico-nutritional problems due to monotonous consumption of starchy cassava roots or protein-rich grass pea seeds as a staple, especially during drought and famine periods. Both foods contain toxic metabolites (cyanogenic glycosides in cassava and the neuro-excitatory amino acid ?-ODAP in grass pea) that are blamed for theses diseases. The etiology is also linked to the deficiency in the essential sulfur amino acids that protect against oxidative stress. The two diseases are not considered reportable by the World Health Organization (WHO) and only estimated numbers can be found. This paper analyzes research performance and determines scientific interest in konzo and neurolathyrism. A literature search of over 21 years (from 1990 to 2010) shows that in terms of scientific publications there is little interest in these neglected motorneurone diseases konzo and neurolathyrism that paralyze the legs. Comparison is made with HTLV-1/TSP, an infectious disease occurring mainly in Latin America of which the clinical manifestation is similar to konzo and neurolathyrism and requires a differential diagnosis. Our findings emphasize the multidisciplinary nature of studies on these neglected diseases, which however have not really captured the attention of decision makers and project planners, especially when compared with the infectious HTLV-1/TSP. Konzo and neurolathyrism can be prevented by a balanced diet. PMID:22860149

Ngudi, Delphin Diasolua; Kuo, Yu-Haey; Van Montagu, Marc; Lambein, Fernand

2012-07-31

287

Differential Effects of Cooked Common Bean (Phaseolus vulgaris) and Lentil (Lens esculenta puyensis) Feeding on Protein and Nucleic Acid Contents in Intestines, Liver and Muscles in Rats  

Microsoft Academic Search

Aim: Our aim was to investigate the influence of legume feeding on the protein and nucleic acid content of intestinal tissues and muscles. Methods: Growing male Wistar rats were fed ad libitum on balanced diets containing cooked common bean or lentil as the unique protein source (180 g·kg–1 dry matter) for 20 days. The control group was pair-fed with an

Tatjana Pirman; Etiennette Combe; Philippe Patureau Mirand; Jasna Stekar; Andrej Orešnik

2004-01-01

288

Morphological correlates of aquatic and terrestrial locomotion in a semi-aquatic frog, Rana esculenta: no evidence for a design conflict  

Microsoft Academic Search

Semi-aquatic frogs are faced with an unusual locomotory challenge. They have to swim and jump using the same apparatus, i.e. the hind limbs. Optimization of two tasks that require mutually incompatible morphologies or physiologies cannot occur simultaneously. In such cases, natural selection will result in some compromise, i.e. an inter- mediate phenotype that can perform both tasks reasonably well, but

Sandra Nauwelaerts; Jason Ramsay; Peter Aerts

2007-01-01

289

Premitotic DNA synthesis in the brain of the adult frog (Rana esculenta L. ): An autoradiographic sup 3 H-thymidine study  

SciTech Connect

Replicative synthesis of DNA in the brain of the adult frog was studied by light microscope autoradiography. Animals collected during the active period (May-June) and in hibernation (January) were used. In active frogs, 3H-thymidine labelling occurred mainly in the ependymal cells which line the ventricles. The mean labelling index (LI%) was higher in the ependyma of the lateral and fourth ventricles than in the ependyma of the lateral diencephalon and tectal parts of the mesencephalon. In the recessus infundibularis and preopticus the number of labelled cells (LCs) was several times greater than in the lateral parts of the third ventricle. LCs were seen subependymally only occasionally. The incidence of LCs in the parenchyma of the brain was much lower in most regions than in the ventricular ependyma; LCs were mainly small and, from their nuclear morphology, they were glial cells. The LI% reached the highest value in the septum hippocampi and in the nucleus entopeduncularis. In these locations, LCs were larger and closer in size to the nerve cells of these regions. From comparison with data obtained earlier in the brain of mammals, it is evident that the distribution of proliferating cells in the olfactory and limbic system is phylogenetically conservative. The occurrence of pyknotic cells in the same areas which contain LCs, suggests that cell division reflects in part the process of cell renewal observed in mammals. However, proliferating cells could also be linked to the continuous growth observed in non-mammalian vertebrates. In hibernating frogs, LCs and pyknoses were not seen or were found occasionally, which further indicates the functional significance of both processes.

Bernocchi, G.; Scherini, E.; Giacometti, S.; Mares, V. (Univ. of Pavia (Italy))

1990-12-01

290

A comparative study on the secretory activity of the subcommissural organ in the European green frogs: Rana esculenta, rana lessonae and Rana ridibunda  

Microsoft Academic Search

1. 1. The subcommissural organ (SCO), present in all vertebrates, is situated in the roof of the third brain ventricle, and secretes into this ventricle a glycoproteinaceous, fibre-like structure, the liquor fibe (LF).\\u000a\\u000a2. 2. The three forms of European green frogs diner from each other in the three parameters used to measure the secretory activity of the SCO: the

J. H. B. Diederen; H. G. B. Vullings

1980-01-01

291

Food supply modifies the trade-off between past and future reproduction in a sexual parasite–host system ( Rana esculenta, Rana lessonae )  

Microsoft Academic Search

Life history theory is concerned with the costs of survival, growth and reproduction under different ecological conditions\\u000a and the allocation of resources to meet these costs. Typical approaches used to address these topics include manipulation\\u000a of food resources, followed by measures of subsequent reproductive traits, and measures of the relationship between current\\u000a and future reproductive investment. Rarely, however, do studies

Marc Olivier Waelti; Heinz-Ulrich Reyer

2007-01-01

292

Effect of replacing soybean protein by taro leaf (Colocasia esculenta (L.) Schott) protein on growth performance of exotic (Landrace × Yorkshire) and native (Moo Lath) Lao pigs.  

PubMed

The impact of replacing soybean crude protein (CP) with CP from ensiled taro leaves (ET) on growth performance, carcass traits, and organ weights in Landrace × Yorkshire (LY) and Moo Lath (ML) Lao pigs was studied. Twenty-four castrated male pigs, 12 of each breed, were allocated to the treatments according to a completely randomized 3 × 2 factorial (three levels of ET × two breeds) arrangement with four pigs per treatment. The pigs were kept in individual pens and were fed at 4 % dry matter of body weight for 105 days. The control diet (ET0) was formulated with soybean meal as the main CP source, and in the other two diets, soybean CP was replaced to 25 % (ET25) and 50 % (ET50), respectively, with CP from ensiled taro leaves. Calculated metabolizable energy intake decreased with increasing replacement of soybean CP in the diet, while dry matter intake (DMI), CP intake (CPI), average daily gain (ADG), and feed conversion ratio (FCR) were unaffected. Carcass weight, back fat thickness, and dressing percentage were unaffected by soybean CP replacement, while organ weights (except for spleen) increased (P < 0.001) when soybean CP was replaced by CP from ensiled taro leaves in the diet. LY pigs had higher (P < 0.001) DMI, CPI, and ADG and better (P < 0.001) FCR than ML pigs. LY pigs had higher carcass weight (P < 0.001), lower back fat thickness (P < 0.001), and higher organ weights (P < 0.05-0.001) than the ML pigs. In conclusion, taro leaf silage can replace up to 50 % of soybean CP in the diet of growing Lao LY and ML pigs without negative effects on performance and carcass traits. PMID:22610600

Kaensombath, Lampheuy; Lindberg, Jan Erik

2012-05-21

293

Ca Salts of the Saccus Endolymphaticus and Processes of Calcification of Bones During Normal and Experimental Metamorphosis in Tadpoles of Bufo Vulgaris, Rana Dalmatina and Rana Esculenta.  

National Technical Information Service (NTIS)

The feeding of tadpoles with thymus was found to have no significant effect on the size of the animals, the development of the saccus endolymphaticus, its Ca salt content or bone calcification. Experiments on exposure to thyroxine seem to indicate that th...

A. Guardabassi

1975-01-01

294

Simultaneous virus-specific detection of the two cassava brown streak-associated viruses by RT-PCR reveals wide distribution in East Africa, mixed infections, and infections in Manihot glaziovii  

Microsoft Academic Search

The expanding cassava brown streak disease (CBSD) epidemic in East Africa is caused by two ipomoviruses (genus Ipomovirus; Potyviridae), namely, Cassava brown streak virus (CBSV), and Ugandan cassava brown streak virus (UCBSV) that was described recently. A reverse transcription polymerase chain reaction (RT-PCR) based diagnostic method was developed in this study for simultaneous virus-specific detection of the two viruses. Results

D. R. Mbanzibwa; Y. P. Tian; A. K. Tugume; S. B. Mukasa; F. Tairo; S. Kyamanywa; A. Kullaya; J. P. T. Valkonen

2011-01-01

295

Quality changes in dehydrated dasheen leaves: effects of blanching pre-treatments and drying conditions  

Microsoft Academic Search

The quality of dasheen leaves (Colocasia esculenta Linn Schott var. esculenta) dried at temperatures ranging from 40 to 70 ° C and under both natural and forced convection conditions was studied, in an attempt to develop a dehydrated product from this popular vegetable, often used in soups and commonly called ‘callaloo’. The effects of various pre-treatments on the quality of

Vashti Maharaj; Clement K. Sankat

1996-01-01

296

Linked basin sedimentation and orogenic uplift: The Neogene Barinas basin sediments derived from the Venezuelan Andes  

NASA Astrophysics Data System (ADS)

The Venezuelan Andes are an asymmetric, doubly vergent orogen that is flanked on its southeastern side by the Barinas basin. Analyses of sedimentary facies, sandstone petrography, apatite fission-tracks, and magnetostratigraphy were completed on a 1750-m section of the syn-orogenic Neogene Parángula and Río Yuca formations in the Barinas side foothills of the Venezuelan Andes. Our sedimentary facies analyses record a progression of sedimentary environments from floodplain and floodplain channel deposits through the 560-m thick Parángula Formation transitioning to distal alluvial fan deposits in the lower Río Yuca Formation and finally to an alternation of distal alluvial fan and two, ˜100-m thick organic-rich lacustrine deposits in the upper third of the section. Major- and minor-mineral petrographic analysis reveals unroofing of the Venezuelan Andes, with quartz arenite composition low in the section succeeded by metamorphic and igneous clasts and potassium feldspar appearing near the base of the Río Yuca Formation. Apatite fission-track (AFT) analysis of sandstones and pebbles generated ages of 11.2 ± 1.3 - 13.8 ± 2.0 Ma over ˜1100 m of stratigraphic section. Thermal modeling of the detrital AFT and vitrinite data from the lower Río Yuca Formation indicates exhumation of the source area was occurring by 12-13 Ma, surface exposure at 10-9 Ma, maximum burial by 4-2 Ma and exhumation of the sedimentary package starting 3-2 Ma. Accumulation of the Río Yuca Formation is contemporaneous with a basinward migration of the deformation front. Regional considerations indicate that the Venezuelan Andes evolved from a primarily singly vergent orogen to its current double vergence over the interval of Neogene-Quaternary sedimentation.

Erikson, Johan P.; Kelley, Shari A.; Osmolovsky, Peter; Verosub, Kenneth L.

2012-11-01

297

Estimation of proximate composition, micronutrients and phytochemical compounds in traditional vegetables from Andaman and Nicobar Islands.  

PubMed

In present study, 10 preferred traditional vegetables from Andaman and Nicobar Islands, India, were analysed for nutritional profiles. Moisture content in their edible parts ranged from 83.43 to 94.78%. Maximum ash content was recorded in Portulaca oleracea, crude protein in Colocasia esculenta, crude fibre in Eryngium foetidum and fat in E. foetidum. Phosphorus was maximum in Ipomea aquatica, potassium in C. esculenta, zinc, calcium and manganese in Centella asiatica, copper in Sauropus androgynous, sodium and iron in P. oleracea, magnesium in Amaranthus viridi and cobalt in C. esculenta. Maximum polyphenol was recorded in Hibiscus sabdariffa, carotenoids in A. viridi, ascorbic acid in Saursops androgynus, anthocyanin in C. esculenta and chlorophyll in S. androgynus. Antioxidant activity was maximum in P. oleracea. Positive correlation was observed between polyphenol and tannin content and also between antioxidant activity and photochemicals. The developed nutritional profiles is being used in health and nutrition related schemes in Islands. PMID:21615278

Singh, Shrawan; Singh, D R; Salim, K M; Srivastava, Amit; Singh, L B; Srivastava, R C

2011-05-26

298

Bad Bug Book Symptomatic diagnoses of mushroom ...  

Center for Food Safety and Applied Nutrition (CFSAN)

... and related hydrazones from Gyromitra esculenta and its relatives, Complete recovery within 2-6 days; may require correction of metabolic acidosis ... More results from www.fda.gov/food/foodborneillnesscontaminants/causesofillnessbadbugbook

299

Experimental culture of Alaria in a sub-arctic, free-flowing sea water system  

Microsoft Academic Search

Kurzfassung Zur Zeit kennt man in Neufundland drei Arten der Braunalgen-GattungAlaria: A. esculenta (L.)Grev.,A. grandifolia.J. Ag. undA. pylaii (Bory)J. Ag. Da neuere Untersuchungen jedoch gezeigt haben, daß viele der neufundländischenAlaria-Exemplare nicht mit Sicherheit zu identifizieren sind, muß die Artbestimmung experimentell erfolgen. Es wird eine Tankkultur von Sporophyten derAlaria esculenta in fließendem und filtriertem Meerwasser bei künstlicher Beleuchtung beschrieben. Die Algen,

G. R. South

1970-01-01

300

Distribution of mRNA encoding the FA-CHIP water channel in amphibian tissues: Effects of salt adaptation  

Microsoft Academic Search

A water channel, the frog aquaporin-CHIP (FA-CHIP) was recently cloned from Rana esculenta urinary bladder. The 28.9 kDa encoded protein shows 78.8%, 77.4%, 42.4% and 35.6% identity with rat CHIP28, human CHIP28, rat WCH-CD and ?-TIP, other members of the new transmembrane water channel family (Aquaporin-CHIP). We have now studied membranes from different frog (R. esculenta) organs employing semiquantitative PCR

L. Abrami; C. Capurro; C. Ibarra; M. Parisi; J.-M. Buhler; P. Ripoche

1995-01-01

301

MODELING OF WATER ACTIVITY AND ENTHALPY OF WATER SORPTION IN CASSAVA CHIPS  

Microsoft Academic Search

The Guggenheim-Anderson-de Boer (G.A.B.) and modified Henderson equations adjusted by linear and non-linear regression were used for mathematical description of sorption isotherms of yuca. The highest result of generalized correlation coefficient was obtained by the G.A.B. direct nonlinear regression. Weighted linear regression of results for isosteric heat sorption must be employed to fit the Clausius-Clapeyron equation.

M. Salgado Cervantes; M. A. Garcia Alvarado; K. N. Waliszewski; Kubiak

1994-01-01

302

Evaluation of cryogenic procedures for cryopreservation of Cassava genotypes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cassava (Manihot esculent Crantz) is a perennial plant widely grown in many tropical countries as one of the most important commercial crops. The global cassava production in 2009 was at 242 million tons. Because of its economic importance to a large number of developing world, the application of ad...

303

Solar dryer for yam flakes and cassava chips  

Microsoft Academic Search

A solar dryer was designed for drying yam (Dioscorea rotundata) flakes and cassava (Manihot utilissima) chips and constructed from locally available materials. The performance of the dryer was tested and yielded very promising results. One major factor considered in the design was to ensure ease of fabrication with readily available local materials. Details of the design features and construction are

M. A. Onilude; O. A. Oloso

1988-01-01

304

Molecular genetic evidence for the transfer of Oerskovia species into the genus Cellulomonas  

Microsoft Academic Search

A close genetic relationship among strains of Oerskovia turbata, O. xanthineolytica and various coryneforms is indicated by DNA-DNA reassociation studies. O. xanthineolytica shares high homology values (over 60%) with Cellulomonas cartae, Nocardia cellulans, Brevibacterium fermentans and Corynebacterium manihot. O. turbata and other cellulomonads show lower DNA homology values (20–25%) which are still high enough, however, to indicate a relationship at

Erko Stackebrandt; Mathias Hfiringer; Karl-Heinz Schleifer

1980-01-01

305

Ecotoxicological effects of cadmium on three ornamental plants.  

PubMed

Ecotoxicological effects of cadmium (Cd) on three ornamental plants African marigold (Tagetes erecta), scarlet sage (Salvia splendens) and sweet hibiscus (Abelmoschus manihot) were investigated. Seeds of these plants were exposed to five different concentrations of Cd (0-50 mgl(-1)). Ecotoxicological indexes based on inhibition rate (IC) of seed germination, root and shoot elongation, biomass (fresh weight and dry weight), as well as IC50 (Cd concentration when 50% plants show inhibition) and tolerance indexes (the ratio of maximum root length in an experimental group to that in a control group) were determined. The results indicated that Cd had little effects (p>0.05) on seed germination of the three plants and shoot elongation of scarlet sage (S. splendens). Cadmium had significant (p<0.05) inhibitory effects on root elongation of the three plants and shoot elongation of African marigold (T. erecta). The fresh weight biomass of scarlet sage (S. splendens) was most sensitive to Cd, while that of sweet hibiscus (A. manihot) was least sensitive. On a dry weight basis, African marigold (T. erecta) was the least sensitive, and scarlet sage (S. splendens) was the most sensitive to Cd. Based on IC50 of seed germination, sweet hibiscus (A. manihot) was the most insensitive plant with an IC50 value as high as 428.0 gl(-1). According to Cd-tolerance indexes under the same Cd concentration, sweet hibiscus (A. manihot) was the most tolerant plant whereas scarlet sage (S. splendens) was the most sensitive one. PMID:15910897

Wang, Xiao-Fei; Zhou, Qi-Xing

2005-06-01

306

AN EST RESOURCE FOR CASSAVA AND OTHER SPECIES OF EUPHORBIACEAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cassava (Manihot esuculenta) is a major food staple for over 600 million people in Africa, Asia, and Latin America. Major losses in yield result from biotic and abiotic stresses that include diseases such as Cassava Mosaic Disease (CMD) and Cassava Bacterial Blight (CBB), drought, and acid soils. A...

307

Seed oil and Fatty acid content in okra (Abelmoschus esculentus) and related species  

Technology Transfer Automated Retrieval System (TEKTRAN)

Approximately 1100 genebank accessions of okra (Abelmoschus esculentus) and 540 additional accessions that included six of its related species were evaluated for seed oil content using TD-NMR. Species evaluated included; A. caillei, A. crinitis, A. esculentus, A. ficulneus, A. manihot, A. moschat...

308

Expression of 5S rDNA in the oocytes of water frogs  

PubMed Central

Background We report the expression pattern of 5S rDNA in the eggs of water frogs Rana lessonae, Rana ridibunda and Rana esculenta using the quantitative real-time PCR. This kind of research had never been performed before. Results 5S rDNA relative expression of the Rana ridibunda oocytes is approximately six times higher in comparison to the Rana lessonae oocytes. The oocytes of the investigated Rana esculenta frogs, in respect of 5S rDNA relative expression ratio, were very similar to the Rana ridibunda oocytes. Conclusion We suggest the possibility of using 5S rDNA as the internal control gene, in the studies of relative mRNA quantitative assays in water frog oocytes, because of its characteristic specific expression pattern in the Rana lessonae, Rana ridibunda and Rana esculenta oocytes.

Czarniewska, Elzbieta; Plewa, Robert

2009-01-01

309

Ricerche morfologiche ed istochimiche sulla glia del nevrasse di vertebrati  

Microsoft Academic Search

Con metodi istochimici e con metodi di colorazione e di impregnazione per il tessuto gliale fu studiato il materiale intercellulare interposto ai neuroni e fibre nervose nel nevrasse di anfibi urodeli ed anuri (Triton taeniatus, Triton cristatus, Amblystoma mexicanum, Xenopus laevis, Bufo vulgaris, Rana esculenta).

A. Bairati; G. Tripoli

1954-01-01

310

Adrenergic receptors of the frog myocardium as iron-containing complexes  

Microsoft Academic Search

METHOD The hearts of winter frogs (Rana esculenta), isolated by Straub's method and perfused with Ringer's solution, were used in the experiments. The positive in, tropic effect of the substances used was assessed from the increase in amplitude of cardiac contractions above the initial value, taken as 100%. The mean value of the effect was determined by averaging the results

I. V. Komissarov; G. I. Reutskaya

1969-01-01

311

Effect of Aspergillus niger on shoot emergence and vine development in field-sown yams ( Dioscorea spp.) and rot development under long-term storage conditions  

Microsoft Academic Search

The effects of infection of seed yam by Aspergillus niger on shoot emergence and vine development were investigated in three yam species. Shoot emergence was particularly poor in D. esculenta; this was attributed to a greater susceptibility to A. niger due to the relatively smaller size of the tuber, less compact inner tissue and thinner periderm in the species. Reductions

M. O. Otusanya; M. J. Jeger

1996-01-01

312

Scyphozoan jellyfish venom metalloproteinases and their role in the cytotoxicity  

Microsoft Academic Search

The present study, for the first time, comparatively investigated the enzymatic activities (proteases and hyaluronidases) in the venoms of four Scyphozoan jellyfish species, including Nemopilema nomurai, Rhopilema esculenta, Cyanea nozakii, and Aurelia aurita. For this, various zymographic analyses were performed using assay specific substrates. Interestingly, all the four jellyfish venoms showed gelatinolytic, caseinolytic, and fibrinolytic activities, each of which contains

Hyunkyoung Lee; Eun-sun Jung; Changkeun Kang; Won Duk Yoon; Jong-Shu Kim; Euikyung Kim

2011-01-01

313

Development of Gocken Multiplication Technology for Cocoyam  

Microsoft Academic Search

Low multiplication ratio of cocoyam {Colocasia esculenta (taro) and Xanthosoma mafafa (tannia)} and scarcity of planting materials are major constraints militating against sustainable cocoyam production. During harvesting and processing of cocoyam, very small cormels weighing about 7.0 g (micro cormels) and less are discarded as wastes. These ‘wastes’ usually sprout in the wet season to constitute environmental problem. The Gocken

G. O Chukwu; K. I Nwosu; E. N. A Mbanaso; O Onwubiko; B. C Okoye; T. U Madu; H Ogbonye; S. U Nwoko

2009-01-01

314

Temporal variation in community interfaces: kelp-bed boundary dynamics adjacent to persistent urchin barrens  

Microsoft Academic Search

We examined, over 2 years, factors affecting the temporal stability of the lower limit of kelp beds ( Alaria esculenta) at five subtidal sites in the Mingan Islands, northern Gulf of St. Lawrence. The position of the lower limit of the beds varied markedly among sites and over time and was largely controlled by the green sea urchin, Strongylocentrotus droebachiensis, which

P. Gagnon; J. H. Himmelman; L. E. Johnson

2004-01-01

315

Susceptibility of zoospores to UV radiation determines upper depth distribution limit of Arctic kelps: evidence through field experiments  

Microsoft Academic Search

Summary 1 The UV susceptibility of zoospores of the brown seaweeds Saccorhiza dermatodea , Alaria esculenta and Laminaria digitata (Laminariales) was determined in field experi- ments in June 2004 on Spitsbergen (78 ° 55 ' N, 11 ° 56 ' E). 2 Freshly released zoospores were exposed for 1 or 2 days at various water depths to ambient solar radiation,

CHRISTIAN WIENCKE; MICHAEL Y. ROLEDA; ANSGAR GRUBER; MARGARET N. CLAYTON; KAI BISCHOF

2006-01-01

316

Exposure to ultraviolet radiation delays photosynthetic recovery in Arctic kelp zoospores  

Microsoft Academic Search

Seasonal reproduction in some Arctic Laminariales coincides with increased UV-B radiation due to stratospheric ozone depletion and relatively high water temperatures during polar spring. To find out the capacity to cope with different spectral irradiance, the kinetics of photosynthetic recovery was investigated in zoospores of four Arctic species of the order Laminariales, the kelps Saccorhiza dermatodea, Alaria esculenta, Laminaria digitata,

Michael Y. Roleda; Dieter Hanelt; Christian Wiencke

2006-01-01

317

Do sulphuric acid and the brown alga Desmarestia viridis support community structure in Arctic kelp patches by altering grazing impact, distribution patterns, and behaviour of sea urchins?  

Microsoft Academic Search

Macrobenthic community structure and the distribution of the green sea urchin (Strongylocentrotus droebachiensis) were recorded inside and outside (=barrens) of kelp patches (Alaria esculenta) at Kongsfjordneset, Svalbard between August 2002 and October 2006. In manipulative field experiments, conducted at Kongsfjordneset,\\u000a Svalbard in August 2002, the effect of the presence of the brown seaweed Desmarestia viridis on sea urchin distribution and

Markus Molis; Hendrik Wessels; Wilhelm Hagen; Ulf Karsten; Christian Wiencke

2009-01-01

318

Foods and predators of the green sea urchin Strongylocentrotus droebachiensis in Newfoundland waters  

Microsoft Academic Search

Gut analyses of the green sea urchin Strongylocentrotus droebachiensis (O. F. Müller) demonstrated that perennial phaeophytes, mostly fucoids and Alaria esculenta, were predominant in the diet. Ephemeral species, coralline algae and animals, were consumed in smaller amounts when available. Grazing by the urchins is evidently responsible for the dearth of non-coralline sublittoral algae in Newfoundland waters. Lobsters, rock crabs, purple

J. H. Himmelman; D. H. Steele

1971-01-01

319

Green urchin as a significant source of fecal particulate organic matter within nearshore benthic ecosystems  

Microsoft Academic Search

The role of green sea urchin Strongylocentrotus droebachiensis as a source of fecal particulate organic matter (POM) for the benthic nearshore ecosystems has been studied over a 3.5-month period. Three macroalgae were tested as food sources: Alaria esculenta, Laminaria longicruris and Ulvaria obscura. Urchins were fed ad libitum with either a single alga species or a mixture of all three

Jean Mamelona; Émilien Pelletier

2005-01-01

320

Sexual hybridization experiments and phylogenetic relationships as inferred from rubisco spacer sequences in the genus alaria (phaeophyceae)  

Microsoft Academic Search

Alaria (Alariaceae, Phaeophyceae) is a common genus of kelps generally found in the lower intertidal and shallow subtidal regions of rocky shores subject to strong wave exposure. Fourteen species are cur- rently recognized, of which 11 are found in the cold- temperate North Pacific Ocean. Alaria esculenta (L.) Greville, the type species described from the North Atlantic, exhibits a range

Stefan Kraan; Michael D. Guiry

2000-01-01

321

Effect of photon irradiance and photoperiod on young sporophytes of four species of the Laminariales  

Microsoft Academic Search

Four kelp species (Alaria esculenta, Laminaria digitata, L. hyperborea and L. saccharina) were cultured in the laboratory and pretreated so that gametophytes became mature and sporophytes were produced. Young sporophytes less than 3 weeks old were exposed to various light conditions and their survival or relative growth rate in length (RL), and width (RW) in one experiment, determined. Sporophytes of

Taejun Han; Joanna M. Kain

1996-01-01

322

Fauna associated with detached kelp in different types of subtidal habitats of the White Sea  

Microsoft Academic Search

The fauna, associated with Laminaria and other largebrown macroalgae was studied by using SCUBA anddredging in two different types of underwater habitatsof the White Sea.In shallow water fjords and bays, with a depth of nomore than 30–40 m, detached kelp (mainly Laminaria saccharina, L. digitata and Alaria esculenta) formed large accumulations. One ofthese benthic accumulations, which has existed morethan 20

A. B. Tzetlin; V. O. Mokievsky; A. N. Melnikov; M. V. Saphonov; T. G. Simdyanov; I. E. Ivanov

1997-01-01

323

Oat Smut as an Artist's Pigment  

Microsoft Academic Search

WITH regard to Prof. Marshall Ward's note under this heading (p. 389, ante), I may add that, according to Mr. K. Miyabe, the olive-brown spores of Ustilago esculenta (``Makomo-zumi'' in Japanese), besides its application to the painting of the ladies' eyebrows in Japan, are mixed up with oil and smeared on the scalp and hairs by older women who have

Kumagusu Minakata

1898-01-01

324

New plant disease records in New Zealand: Miscellaneous fungal pathogens II  

Microsoft Academic Search

Ten fungi, Cladosporium colocasiae Sawada (on Colocasia esculenta (L.) Schott), Colletotrichum malvarum (Braun et Casp.) Southworth (on Lavatera sp.), Frommeella duchesneae (Arthur) Yohem, Cummins etGilbertson (on Duchesnea indica (Andrews) Focke), Hyalopsora polypodii (Diet.) Magnus (on Deparia petersenii (Kunze) Kato ssp. congrua (Brackenr.) Kato), Mycocentrospora cladosporioides (Sacc.) P. Costa ex Deighton (on Olea europaea L.), Phaeoramularia eupatorii-odorati (Yen) Liu et Guo

E. H. C. McKenzie

1990-01-01

325

Nitrogen requirements of taro  

Microsoft Academic Search

Taro [Colocasia esculenta (L.) Schott] is an important root crop in the tropics. Under optimum conditions, the crop develops a large leaf area and accumulates substantial amounts of dry matter in the corms. To support this high biomass production, the crop requires large amounts of nitrogen (N). Excessive N fertilization, however, favors top growth, reduces the proportion of dry matter

Luis A. Manrique

1994-01-01

326

Medicinal Plant Resources in Chhakinal Watershed in the Northwestern Himalaya  

Microsoft Academic Search

Traditional knowledge, uses, monetary costs, and benefits associated with medicinal plants were analyzed in the Chhakinal watershed of Northwestern Himalaya. Of 29 plant species used in folk medicine, only 3 species, Juglans regia, Picrorrhiza kurrooa, and Morchella esculenta were noted to have market value. The medicinal value of four species, Dioscorea deltoidea, Podophyllum hexandrum, Valeriana jatamansi, and Jurinea macrocephala, were

R. M. Dobriyal; G. S. Singh; K. S. Rao; K. G. Saxena

1997-01-01

327

Temporal Resource Switching by Ants between Honeydew Produced by the Fivespotted Gama Grass Leafhopper (Dalbulus quinquenotatus) and Nectar Produced by Plants with Extrafloral Nectaries  

Microsoft Academic Search

A field study was conducted in Jalisco, Mexico, to quantify temporal resource switching by ants between honeydew produced by the fivespotted gama grass leafhopper, Dalbulus quinquenotatus, and nectar produced by plants with extrafloral nectaries (EFNs). Four plant taxa (Acacia pennatula, Leucaena esculenta, Lobelia laxiflora and Lysilona sp.) which produced nectar from EFNs were monitored for ants during the dry and

GUSTAVO MOYA-RAYGOZA; KIRK J. LARSEN

2001-01-01

328

DEVELOPMENT OF A GENETIC TRANSFORMATION AND REGENERATION SYSTEM FOR TARO  

Technology Transfer Automated Retrieval System (TEKTRAN)

Taro (Colocasia esculenta) is an important staple crop in the Pacific Islands. To improve resistance of taro to fungal pathogens, a genetic transformation and regeneration system has been developed. Highly regenerative taro calli of cv. Bun Long were obtained in a Murashige and Skoog (MS) medium wit...

329

Distribution of carbonic anhydrase in British marine macroalgae  

Microsoft Academic Search

Thirty-four species of marine macroalgae from around St. Andrews, Scotland, have been assayed for their external activity and thirty-three species for their total activity of carbonic anhydrase. Activity was detected in all the Rhodophyta tested apart from Chondrus crispus, but was absent in Codium fragile, Enteromorpha sp. and Monostroma fuscum (Chlorophyta), and Alaria esculenta, Laminaria digitata, L. saccharina and L.

M. Giordano; S. C. Maberly

1989-01-01

330

Comparative studies on the nutrition of two species of abalone, Haliotis tuberculata L. and Haliotis discus hannai Ino. V. The role of polyunsaturated fatty acids of macroalgae in abalone nutrition  

Microsoft Academic Search

This study was undertaken to evaluate the nutritional role of polyunsaturated fatty acids (PUFA) in dietary macroalgae for the abalone, Haliotis tuberculata and Haliotis discus hannai. The effects of five species of macroalgae (Alarla esculenta, Laminaria digitata, Laminaria saccharina, Palmaria palmata and Ulva lactuca) on specific growth rates (SGR) of the abalone and, the relationship between abalone SGR and fatty

Kangsen Mai; John P. Mercer; John Donlon

1996-01-01

331

Antioxidant activity of the mycelium of 21 wild mushroom species  

Microsoft Academic Search

In this study, the antioxidant activity of mycelia from 21 wild mushrooms – Agaricus bresadolanus, Auricularia auricula-judae, Chroogomphus rutilus, Fomes fomentarius, Ganoderma lucidum, Gloeophyllum trabeum, Gymnopus dryophilus, Infundibulicybe geotropa, Inocybe flocculosa var. crocifolia, Inocybe catalaunica, Lentinula edodes, Lentinus sajor-caju, Lycoperdon excipuliforme, Macrolepiota excoriata, Morchella esculenta var. rigida, Morchella intermedia, Omphalotus olearius, Pleurotus djamor, Postia stiptica, Rhizopogon roseolus and Stropharia inuncta

Fatih Kalyoncu; Mustafa Oskay; Hüsniye Kayalar

2010-01-01

332

Mechanical Transmission of Cassava Brown Streak Virus  

Microsoft Academic Search

BROWN streak virus disease of cassava (Manihot utilissima Pohl.) is important in all the cassava-growing areas on the coasts of Kenya and Tanganyika, because necrosis of the starch storage tissues of the roots and stems of infected plants results in serious losses in yield1,2. Transmission of the virus by a white fly (Bemisia sp.) is suspected but has not been

R. M. Lister

1959-01-01

333

Cyanide content of cassava mash and gari flour and influence of water activity (a w ) during storage  

Microsoft Academic Search

Cyanide occurs in many plants mainly in the form of cyanogenetic glycosides (Montgomery 1969). The lethal dose of HCN for man is in the order 0.5-3.5 mg\\/kg body weight (Wogan 1976). Diseases such as tropical ataxic neuropathy and goitre have been associated with cyanide intakes ~suntokun 1968; Osuntokun 1969). Cassava (Manihot) and gari fleur obtained from cassava mash by-- e~-œ

Mark E. Ukhun; Edward N. Dibie

1989-01-01

334

Tetraploids, triploids, and 2n pollen from diploid interspecific crosses with cassava  

Microsoft Academic Search

Interspecific crosses of five cultivated cassava varieties (2n=36) were made with two related Manihot species, M. epruinosa (2n=36) and M. glaziovii (2n=36). From these diploid interspecific crosses, four spontaneous tetraploids (2n=4x=72) and two triploids (2n=3x=54) were isolated for the first time in cassava. Occurrence of relatively high frequencies (0.1%–35.6%) of 2n pollen and of apomixis seems to be associated with

S. K. Hahn; K. V. Bai; R. Asiedu

1990-01-01

335

Weitere Untersuchungen über Chromosomenverhältnisse und DNS-Gehalt bei Anuren (Amphibia)  

Microsoft Academic Search

The karyotypes of the toad Bufo marinus L. (2n=22) and the frogs Limnodynastes tasmaniensisGthr. (2n=24), Rana temporaria L., R. esculenta L. (both 2n=26) and R. arvalisNills. (2n=24) were analysed in colchicine treated leukocyte and spermatogonial metaphases and\\/or embryonic and larval mitoses. The DNA content of Feulgen stained erythrocyte nuclei was measured microspectrophotometrically. Heteromorphic sex chromosomes are absent in all species.

Fritz-Helmut Ullerich

1967-01-01

336

Crossed effects on central vestibular neurons in the horizontal canal system of the frog  

Microsoft Academic Search

Summary  \\u000a1. \\u000aNeuronal discharges were recorded extracellularly in curarized frogs (Rana esculenta) with glassmicropipettes. Vestibular neurons, which were activated by ipsilateral horizontal angular acceleration and suppressed during deceleration (type 1) were found mainly in the medial part of the ventral vestibular nucleus.\\u000a2. \\u000aIn contrast to type 1 vestibular neuron of the cat, this type of neuron in the frog

S. Ozawa; W. Precht; H. Shimazu

1974-01-01

337

Aluminium localization in amphibian skin with the electron microprobe and ion microanalyzer.  

PubMed

EMP and IMA studies show the presence of A1 in the epidermis of larvae and young adults of Discoglossus pictus and Rana esculenta, which disappears during later stages of development. A1 is practically absent in the epidermis of Xenopus laevis and Pleurodeles waltlii. The localization of A1 with EMP and IMA supports the biochemical results. The function of A1 in the epidermis is not known at present. PMID:1083571

Hourdry, J; Truchet, M

1976-01-01

338

Effects of a synthetic cationic polymer on sodium and potassium currents of frog nerve fibres  

Microsoft Academic Search

(1) Voltage-clamped nerve fibres of the frogRana esculenta were treated with the synthetic cationic polymer hexadimethrine bromide (HDM) [Polybrene]. (2) 1 ?M HDM irreversibly reducedI\\u000a Na to about 65% of its original size. The time to peak remained almost unaffected, while the decaying phase of the currents\\u000a (for pulse potentials I\\u000a Na was hardly reduced further even with a 1,000-fold

Michael Rack; Gisela Drews

1989-01-01

339

Microelectrode studies of the effect of lanthanum on the electrical potential and resistance of outer and inner cell membranes of isolated frog skin  

Microsoft Academic Search

Summary Microelectrodes were used to investigate the effect of 0.5mm mucosal lanthanum (La3+) on the intracellular potential and the resistance of outer and inner isolated frog skin (Rana esculenta) cell membranes. Under short-circuit conditions, the transapical membrane potentialVosc (mean value=-65.4±3.2 mV, inside negative) hyperpolarized to -108.7±2.3 mV in control skins, after addition of the sodium blocker amiloride. Current-voltage curves for

H. Goudeau; J. Wietzerbin; E. Mintz; M. P. Gingold; W. Nagel

1982-01-01

340

Above-ground earthworm casts affect water runoff and soil erosion in Northern Vietnam  

Microsoft Academic Search

This manuscript focuses on the effects of above-ground earthworm casts on water runoff and soil erosion in steep-slope ecosystems in Northern Vietnam. We investigated the effects of Amynthas khami, an anecic species producing above-ground casts of prominent size, on water infiltration and soil detachment along a land-use intensification gradient: a cultivation of cassava (Mahinot esculenta; CAS), a plantation of Bracharia

Pascal Jouquet; Pascal Podwojewski; Nicolas Bottinelli; Jérôme Mathieu; Maigualida Ricoy; Didier Orange; Toan Duc Tran; Christian Valentin

2008-01-01

341

Testing the shade tolerance of selected crops under Parkia biglobosa (Jacq.) Benth. in an agroforestry parkland in Burkina Faso, West Africa  

Microsoft Academic Search

In Western Africa, interactions between trees and agricultural crops are a key element in determining parkland management\\u000a in an agricultural environment that is rapidly changing. Eggplant (Solanum melongena), chilli pepper (Capsicum annuum), taro (Colocasia esculenta) and pearl millet (Pennisetum glaucum) were tested for their shade tolerance under Parkia biglobosa trees in south-central Burkina Faso using a split-plot design. Soil characteristics,

Mariève Pouliot; Jules Bayala; Anders Ræbild

342

Search for alternative hosts of banana bunchy top virus in Australia  

Microsoft Academic Search

A range of plant species that are either cultivated, naturalised or indigenous to sub-tropical eastern Australia and are also\\u000a able to sustain feeding by Pentalonia nigronervosa, the vector of banana bunchy top virus (BBTV), were investigated as possible hosts of the virus. Alocasia brisbanensis, Alpinia arundelliana. Alpinia caerulea, Alpinia zerumbet, Canna indica, Colocasia esculenta, Hedychiumcoronarium and Heliconia psittacorum cv. Red

A. D. W. Geering; J. E. Thomas

1997-01-01

343

Effects of water motion on propagule release from algae with complex life histories  

Microsoft Academic Search

Reproductive marine algae with complex life histories may respond differently to water motion depending upon whether the spore-producing or gamete-producing phase is considered. Two such species, the kelp Alaria esculenta (L.) Greville (Phaeophyceae) and Ulva lactuca L. (Chlorophyta), were examined experimentally in the laboratory. The kelp was collected in April–June 2000 and U. lactuca was collected in July–August 2000, from

R. Gordon; S. H. Brawley

2004-01-01

344

Sensitivity and acclimation to UV radiation of zoospores from five species of Laminariales from the Arctic  

Microsoft Academic Search

Spores of five Laminariales from Arctic Spitsbergen were exposed in the laboratory to photosynthetically active radiation (PAR; 400–700 nm), PAR+UVA radiation (UVAR; 320–400 nm) and PAR+UVAR+UVB radiation (UVBR; 280–320 nm). Subsequently, germination was monitored over periods of 3, 6 and 9 days. The investigated species were the upper sublittoral Saccorhiza dermatodea, the upper to mid-sublittoral Alaria esculenta and Laminaria digitata, the mid-sublittoral L. saccharina

C. Wiencke; M. N. Clayton; M. Schoenwaelder

2004-01-01

345

Expression of ?SM actin in terrestrial ectothermic vertebrates  

Microsoft Academic Search

a-Smooth muscle (aSM) actin of endothermic vertebrates is selectively recognized by the monoclonal antibody anti-aSM-1. Immunoreactivity to this antibody has been shown to be localized in the NH2-terminal sequence Ac-EEED (Chaponnier et al. 1994). Among terrestrial ectothermic vertebrates, two amphibian (Triturus vulgaris, Rana esculenta) and three reptilian species (Pseudemys scripta elegans, Natrix natrix, Podarcis sicula) were screened to investigate if

Ines Di Rosa; Fausto Panara; Anna Fagotti; Francesca Simoncelli; Christine Chaponnier; Giulio Gabbiani; Rita Pascolini I

1995-01-01

346

The impact of LED illumination on antioxidant properties of sprouted seeds  

Microsoft Academic Search

The objective of this study was to evaluate the effect of the light emitting diode (LED) spectra on the antioxidant properties\\u000a of sprouted wheat (Triticum aestivum L.), radish (Raphanus sativus L.), and lentil (Lens esculenta Moenh.) seeds. Lighting experiments were performed under controlled conditions (PPFD - 100 ?mol m?2 s?1; 12 h photoperiod; 27°C). The LED conditions used were: L1

Giedr? Samuolien?; Akvil? Urbonavi?i?t?; Aušra Brazaityt?; Gintar? Šabajevien?; Jurga Sakalauskait?; Pavelas Duchovskis

2011-01-01

347

The neural retina of the frog contributes a slow cornea-positive potential to the electroretinogram  

Microsoft Academic Search

A c-wave-like cornea-positive potential in the isolated rabbit retina has been described. In this study, frog retinas were investigated to see if the neural retina contributes a slow cornea-positive component to the c-wave of the electroretinogram. The eye cups of both Rana esculenta and Rana temporaria exhibited a normal electroretinogram with c-wave, a larger proximal light-induced extracellular potassium increase, a

Renate Hanitzsch; Christian Zeumer; Wolf-Ulrich Mättig

1992-01-01

348

Asymmetrical displacement currents in the membrane of frog myelinated nerve: Early time course and effects of membrane potential  

Microsoft Academic Search

1.Asymmetrical displacement currents were studied in myelinated nerve fibres fromRana esculenta with a voltage clamp technique.2.For brief pulses symmetrical with respect to a holding potential of -97 mV, the asymmetry current flowing during pulses (on-response) exhibited a rising phase to a peak followed by an approximately exponential decline. After the pulses the rising phase in the off-response could not be

W. Nonner; E. Rojas; R. Stämpfli

1978-01-01

349

Heterozygous fitness effects of clonally transmitted genomes in waterfrogs  

Microsoft Academic Search

The European waterfrog Rana esculenta (RL-genotype) is a natural hybrid between R. ridibunda (RR) and R. lessonae (LL) and reproduces by hybrido- genesis, i.e. it eliminates the L-genome from the germline and produces gametes only containing the clonally transmitted R-genome. Because of the lack of recombination, R-genomes are prone to accumulate spontaneous deleterious mutations. The homozygous effects of such mutations

C. V ORBURGER

2001-01-01

350

Effects of ultraviolet radiation on photosynthesis and related enzyme reactions of marine macroalgae  

Microsoft Academic Search

.  ?Changes in physiological parameters related to photosynthesis were studied in five macroalgal species from Spitsbergen (Monostroma arcticum, Laminaria solidungula, Alaria esculenta, Palmaria palmata, Phycodrys rubens) during a 72-h exposure to UV radiation. Maximal quantum yield of photochemistry (Fv\\/Fm) and maximal electron transport rate\\u000a (ETRmax) were measured with a pulse-amplitude-modulated fluorometer; the activity of the Calvin cycle enzymes ribulose-1,5-bisphosphate\\u000a carboxylase\\/oxygenase (Rubisco)

Kai Bischof; Dieter Hanelt; Christian Wiencke

2000-01-01

351

Secondary somatic embryogenesis and plant regeneration in cassava  

Microsoft Academic Search

Somatic embryos isolated from mature seed-derived cotyledon cultures of cassava (Mannihot esculenta Crantz) underwent direct secondary somatic embryogenesis or plant development under appropriate incubation conditions. Isolated somatic embryos were subjected to a two-stage culture procedure similar to that which induced their development on cotyledon explants. This involved incubation for 24–30 days on Murashige and Skoog basal medium supplemented with 2–8

James A. Stamp; Graham G. Henshaw

1987-01-01

352

Effects of ultraviolet radiation on photosynthesis and related enzyme reactions of marine macroalgae.  

PubMed

Changes in physiological parameters related to photosynthesis were studied in five macroalgal species from Spitsbergen (Monostroma arcticum, Laminaria solidungula, Alaria esculenta, Palmaria palmata, Phycodrys rubens) during a 72-h exposure to UV radiation. Maximal quantum yield of photochemistry (Fv/Fm) and maximal electron transport rate (ETRmax) were measured with a pulse-amplitude-modulated fluorometer; the activity of the Calvin cycle enzymes ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and glyceraldehyde-3-phosphate dehydrogenase (G3PDH) were estimated using a photometric test. Proteins of crude extracts were separated by SDS gel electrophoresis and changes in cellular concentrations of Rubisco were determined. Moreover, the concentration of chlorophyll a (Ch1 a), and protein content, were measured photometrically. In all species, Ch1 a content, maximal quantum yield as well as ETRmax decreased during the UV treatment. Changes in ETRmax were related to the changes in the overall activity of Rubisco. Analysis of SDS gels showed that in P. rubens, L. solidungula, M. arcticum and A. esculenta decreasing Rubisco activity partly resulted from a degradation of the enzyme. However, in A. esculenta, the formation of a high-molecular-weight polypeptide was observed. In all species, the activity of Rubisco was more strongly impaired than that of G3PDH. Exposure to UV resulted in loss of total protein only in the deepwater species L. solidungula and P. rubens. The different sensitivities to UV exposure of the species tested reflect their zonation pattern in the field. PMID:11030555

Bischof, K; Hanelt, D; Wiencke, C

2000-09-01

353

Removal of furanocoumarins in grapefruit juice by edible fungi.  

PubMed

Furanocoumarins (FCs) in the human diet irreversibly inhibit human cytochrome P450 3A4 (CYP 3A4) and are responsible for the "grapefruit/drug"interaction phenomenon. Previously, we reported that FCs in grapefruit juice (GFJ) bind to autoclaved Aspergillus niger, and this binding reduced the GFJ inhibition of CYP 3A4. However, A. niger is not an edible fungus, and thus, potentially similar binding by edible fungi was also characterized. In this study, autoclaved Morchella esculenta, an edible ascomycete, removed much of the FC content in GFJ, resulting in decreased inhibition of CYP 3A4 activity by the GFJ. Three other edible fungi, Monascus purpureus, Pleurotus sapidus, and Agaricus bisporus, were evaluated for their binding with two of the major FCs in GFJ, 6',7'-dihydroxybergamottin (DHB) and bergamottin (BM). These autoclaved edible fungi removed these FCs from GFJ, similar to M. esculenta, indicating that binding is a general, passive interaction between FCs and fungal hyphae. The removal of FCs was independent of pH in GFJ. Dried fungal material of M. esculenta was also effective in removing FCs from GFJ and occurred with GFJ samples prepared from both fresh grapefruit and GFJ concentrate. PMID:19012403

Myung, Kyung; Narciso, Jan A; Manthey, John A

2008-12-24

354

Widespread unidirectional transfer of mitochondrial DNA: a case in western Palaearctic water frogs.  

PubMed

Interspecies transfer of mitochondrial (mt) DNA is a common phenomenon in plants, invertebrates and vertebrates, normally linked with hybridization of closely related species in zones of sympatry or parapatry. In central Europe, in an area north of 48 degrees N latitude and between 8 degrees and 22 degrees E longitude, western Palaearctic water frogs show massive unidirectional introgression of mtDNA: 33.7% of 407 Rana ridibunda possessed mtDNA specific for Rana lessonae. By contrast, no R. lessonae with R. ridibunda mtDNA was observed. That R. ridibunda with introgressed mitochondrial genomes were found exclusively within the range of the hybrid Rana esculenta and that most hybrids had lessonae mtDNA (90.4% of 335 individuals investigated) is evidence that R. esculenta serves as a vehicle for transfer of lessonae mtDNA into R. ridibunda. Such introgression has occurred several times independently. The abundance and wide distribution of individuals with introgressed mitochondrial genomes show that R. lessonae mt genomes work successfully in a R. ridibunda chromosomal background despite their high sequence divergence from R. ridibunda mtDNAs (14.2-15.2% in the ND2/ND3 genes). Greater effectiveness of enzymes encoded by R. lessonae mtDNA may be advantageous to individuals of R. ridibunda and probably R. esculenta in the northern parts of their ranges. PMID:18373588

Plötner, J; Uzzell, T; Beerli, P; Spolsky, C; Ohst, T; Litvinchuk, S N; Guex, G-D; Reyer, H-U; Hotz, H

2008-03-27

355

Screening of medicinal plants from Trinidad and Tobago for antimicrobial and insecticidal properties.  

PubMed

Antibacterial activity in 51 extracts from 29 plant species currently used in traditional medicine in Trinidad and the neighbouring Caribbean islands was tested for by the agar dilution streak method using six bacteria: Escherichia coli, Pseudomonas aeruginosa. Salmonella tophimurium, Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis. The extracts from eight of the plants tested showed significant activity against one or more micro-organisms and the most susceptible bacterium was Staphylococcus aureus. In the bioassays for toxicity towards the Aedes aegypti mosquito the most effective plant extracts were from Justicia pectoralis, Manihot utilissima and Stachytarpheta jamaicensis. PMID:10363843

Chariandy, C M; Seaforth, C E; Phelps, R H; Pollard, G V; Khambay, B P

1999-03-01

356

Photosynthetic response of Arctic kelp zoospores exposed to radiation and thermal stress.  

PubMed

Zoospores of Arctic kelp species, Alaria esculenta, Laminaria digitata and Saccharina latissima were exposed to different temperature (2 degrees C to 19 degrees C) and radiation (photosynthetically active radiation (PAR=P), PAR+UV-A (PA), and PAR+UV-A+UV-B (PAB)) conditions in the laboratory. Species-specific responses to the combined effect of light and temperature stress showed sensitivity in the order S. latissima>L. digitata>A. esculenta. The optimum temperature range for photosynthesis in different Arctic kelp species' zoospores was between 7-13 degrees C, temperatures higher than in the natural environment. Short-term response to increasing temperature was non-lethal while moderate temperature increase had an ameliorating effect on the overall biological effect of UVR; where the lowest photoinhibition was observed at 13 degrees C under PAB and higher photosynthetic recovery was observed in UVR-pre-exposed zoospores at 7-13 degrees C compared to 2 degrees C. Above the temperature optima, continued cultivation under high temperature had a negative impact on the recovery of photoinhibition. The higher capacity for non-photochemical quenching (NPQ) in A. esculenta and L. digitata helped to regulate and protect photosynthesis under light and temperature stress compared to S. latissima. The investigated Arctic kelp species may be able to locally survive under the influence of UVR at a certain range of temperature increase but the southernmost distribution range of the species may shift to higher latitudes; although natural selection may result in genotypes adapted to stressful environment. PMID:19707618

Roleda, Michael Y

2009-03-19

357

Mitochondrial DNA reveals formation of nonhybrid frogs by natural matings between hemiclonal hybrids.  

PubMed

The European water frog Rana esculenta (RL), a natural hybrid between R. ridibunda (RR) and R. lessonae (LL), reproduces by hybridogenesis: haploid gametes usually contain an intact chromosome set of R. ridibunda (R); the lessonae nuclear genome (L) is lost from the germ line. Hybridity is restored in the next generation, via fertilization by syntopic R. lessonae. Matings between two hybrids (RL x RL) usually give inviable R. ridibunda (RR) progeny. The adult R. ridibunda subpopulation of Trubeschloo, a gravel pit in northern Switzerland, consists only of females. Fragment patterns for mitochondrial DNA (mtDNA) of these R. ridibunda were identical with those of syntopic R. esculenta and of local populations of R. lessonae; they differed from the patterns in eastern European populations of R. lessonae and of R. ridibunda mtDNAs (3.7% and 9.3% estimated sequence divergence, respectively). In contrast, mtDNAs of two R. ridibunda from an introduced Swiss population with both sexes, although different (2.7% divergence) from each other, were typical R. ridibunda rather than R. lessonae mtDNAs. These data, together with unisexuality, demonstrate conclusively that the all-female R. ridibunda population at Trubeschloo originated from matings between two R. esculenta. The formation of independently reproducing R. ridibunda populations via such hybrid x hybrid matings is precluded because progeny of these matings are unisexual. Recombination in the regenerated fertile R. ridibunda females, followed by matings with R. lessonae, nevertheless provides a mechanism for meiotic reshuffling of genetic material in ridibunda haplotypes that is not typically available in hemiclonal lineages. PMID:1352842

Hotz, H; Beerli, P; Spolsky, C

1992-07-01

358

Endocannabinoids and Endovanilloids: A Possible Balance in the Regulation of the Testicular GnRH Signalling  

PubMed Central

Reproductive functions are regulated both at central (brain) and gonadal levels. In this respect, the endocannabinoid system (eCS) has a very influential role. Interestingly, the characterization of eCS has taken many advantages from the usage of animal models different from mammals. Therefore, this review is oriented to summarize the main pieces of evidence regarding eCS coming from the anuran amphibian Rana esculenta, with particular interest to the morphofunctional relationship between eCS and gonadotropin releasing hormone (GnRH). Furthermore, a novel role for endovanilloids in the regulation of a testicular GnRH system will be also discussed.

Ciaramella, Vincenza; Scarpa, Donatella; Fasano, Silvia; Pierantoni, Riccardo

2013-01-01

359

Proton pump activity is required for active uptake of chloride in isolated amphibian skin exposed to freshwater  

Microsoft Academic Search

Net proton secretion and unidirectional chloride fluxes were measured in isolated skin of toads (Bufo bufo) and frogs (Rana esculenta) mounted in an Ussing chamber and exposed to a Ringer's solution on the serosal side and a freshwater-like solution (1-3 mM Cl-) on the external side. Active proton secretion was 34.2DŽ.0 pmol·cm-2·s-1 (n=18) in frog skin, and 16.7ǃ.7 pmol·cm-2·s-1 (n=10)

L. J. Jensen; N. J. Willumsen; E. H. Larsen

2002-01-01

360

Selected emerging diseases of amphibia.  

PubMed

This review summarizes the most recent updates on emerging infectious diseases of amphibia. A brief summary of Batrachochytrium dendrobatidis history, epidemiology, pathogenesis, life cycle, diagnosis, treatment, and biosecurity is provided. Ambystoma tigrinum virus, common midwife toad virus, frog virus 3, Rana grylio virus, Rana catesbeiana ranavirus, Mahaffey Road virus, Rana esculenta virus, Bohle iridovirus, and tiger frog virus ranaviruses are extensively reviewed. Emerging bacterial pathogens are discussed, including Flavobacter sp, Aeromonas sp, Citrobacter freundii, Chlamydophila sp, Mycobacterium liflandii, Elizabethkingia meningoseptica, and Ochrobactrum anthropi. Rhabdias sp, Ribeiroia sp, and Spirometra erinacei are among several of the parasitic infections overviewed in this article. PMID:23642863

Latney, La'Toya V; Klaphake, Eric

2013-03-15

361

[Isolation of active gonadotropin fractions from sturgeon hypophysis and procurement of specific immune sera to them].  

PubMed

The proteins of sturgeon hypophysis form 12 fractions when being separated by disc-electrophoresis. The maturation of the Rana esculenta or Bufo viridis oocytes in vitro served as a criterion of gonadotropic activity of fractions. The gonadotropic activity was shown to reside in two glycoprotein fractions with the mobilities 0.26 and 0.34. The immune serum to the former fraction is monospecific under immunodiffusion and suppresses the oocyte maturation in vitro. The immune serum to the latter fraction is characterized by the antigonadotropic activity as well, but expressed to a lesser extent. PMID:814521

Apekin, V S

1975-01-01

362

EPR investigation of some desiccated Ascomycota and Basidiomycota gamma-irradiated mushrooms  

NASA Astrophysics Data System (ADS)

The suitability of the EPR spectroscopy for detection of ?-irradiation in five species of dried mushroom, currently used in gastronomy: yellow morel—Morchella esculenta, (L.) Pers. (Phylum Ascomycota), button mushroom—Agaricus bisporus (J.E.Lange), Agaricus haemorrhoidarius Fr., golden chantarelle—Cantharellus cibarius Fr., as well as oyster mushroom—Pleurotus ostreatus (Jacq. ex Fr.) (Phylum Basidiomycota) is presented and discussed. Although after irradiation at doses up to 11 kGy, all specimens presented well defined EPR spectra, only A. bisporus EPR signal was enough stable to make detection possible after 18 months.

Bercu, V.; Negut, C. D.; Duliu, O. G.

2010-12-01

363

Screening of the wormicidal Chinese raw drugs on Clonorchis sinensis.  

PubMed

The wormicidal effect on Clonorchis sinensis in boiled water extracts of 223 species (vegetable origin 206, animal origin 10, mineral origin 7) of raw drugs prescribed in Oriental medicine was observed in vitro. The wormicidal substances were detected from 31 of the above-mentioned species. The wormicidal substances extracted from Platycodon grandiflorum (radix), Schizandra chinensis (fruit), Polygala tenuifolia (herb) and Aster tataricus (radix) were most effective. Those from Smilax glabra (radix), Pueraria thunbergiana (flower, radix), Polygala tenuifolia (radix), Scutellaria baicalensis (radix), Prunus mume (fruit), Glycyrrhiza uralensis (radix), Angelica koreana (radix), Phytolacca esculenta (radix) and Cyrtomium fortunei (rhizoma) were effective. The rest of the raw drugs were less effective. PMID:6764091

Rhee, J K; Woo, K J; Baek, B K; Ahn, B J

1981-01-01

364

Dasheen mosaic potyvirus in Hawaiian taro  

Microsoft Academic Search

Indirect enzyme-linked immunosorbant assay (ELISA) procedures were developed to detect dasheen mosaic potyvirus (DsMV) in\\u000a Hawaiian taro (Colocasia esculenta) plantings. This virus was detected from samples equivalent to 0.01 mg taro leaf tissue using either DsMV-specific polyclonal\\u000a antiserum or a commercially available monoclonal broad-spectrum potyvims antibody. The distribution of DsMV within taro plants\\u000a was examined. DsMV titres were higher in

J. S. Hu; S. Meleisea; M. Wang; M. A. Shaarawy; F. W. Zettler

1995-01-01

365

Nutritional values and antioxidant potential of some edible mushrooms of Kashmir valley.  

PubMed

Mushrooms are considered rich in proteins, carbohydrates and other nutrients. The present study was carried out to evaluate some edible mushrooms of Kashmir valley for their protein, carbohydrate and lipid contents. The highest protein content was found in Boletus edulis (2.20g) followed by Agaricus bisporus (1.80g), Pleurotus ostreatus (1.68g), Morchella esculenta (1.62g) and Pleurotus sajor caju (1.6g). Carbohydrate content also showed variation in all the five tested edible mushroom species, the highest carbohydrate content observed in Boletus edulis (6.0g) followed by Agaricus bisporus (4.85g), Pleurotus ostreatus (4.30g), Morchella esculenta (4.25g) and Pleurotus sajor caju (3.35g) respectively. Similar results were observed for lipid content. The present study was also investigated for the antioxidant potential of aqueous extract of mushroom species by the methods of DPPH radical scavenging activity, hydroxyl radical scavenging activity and superoxide radical scavenging activity. All these in vitro antioxidant activities were concentration dependent, which were compared with standard antioxidant Catechin. PMID:22713951

Boda, Rouf Hamza; Wani, Abdul Hamid; Zargar, Mohammad Afzal; Ganie, Bashir Ahmad; Wani, Bilal Ahmad; Ganie, Showkat Ahmad

2012-07-01

366

Scyphozoan jellyfish venom metalloproteinases and their role in the cytotoxicity.  

PubMed

The present study, for the first time, comparatively investigated the enzymatic activities (proteases and hyaluronidases) in the venoms of four Scyphozoan jellyfish species, including Nemopilema nomurai, Rhopilema esculenta, Cyanea nozakii, and Aurelia aurita. For this, various zymographic analyses were performed using assay specific substrates. Interestingly, all the four jellyfish venoms showed gelatinolytic, caseinolytic, and fibrinolytic activities, each of which contains a multitude of enzyme components with molecular weights between 17 and 130 kDa. These four jellyfish venoms demonstrated a huge variation in their proteolytic activities in quantitative and qualitative manner depending on the species. Most of these enzymatic activities were disappeared by the treatment of 1,10-phenanthroline, suggesting they might be belonged to metalloproteinases. Toxicological significance of these venom proteases was examined by comparing their proteolytic activity and the cytotoxicity in NIH 3T3 cells. The relative cytotoxic potency was C. nozakii > N. nomurai > A. aurita > R. esculenta. The cytotoxicity of jellyfish venom shows a positive correlation with its overall proteolytic activity. The metalloproteinases appear to play an important role in the induction of jellyfish venom toxicities. In conclusion, the present report proposes a novel finding of Scyphozoan jellyfish venom metalloproteinases and their potential role in the cytotoxicity. PMID:21718715

Lee, Hyunkyoung; Jung, Eun-sun; Kang, Changkeun; Yoon, Won Duk; Kim, Jong-Shu; Kim, Euikyung

2011-06-23

367

In vitro mycorrhization and acclimatization of Amanita caesareoides and its relatives on Pinus densiflora.  

PubMed

Amanita caesareoides is a sister species of Amanita caesarea, also known as Caesar's mushroom and one of the most desirable edible mycorrhizal mushrooms. However, cultivation of Caesar's mushrooms has not yet been successful due to the difficulties involved in establishing pure cultures. In this study, we established pure cultures of four Asian Caesar's mushroom species, i.e., A. caesareoides, Amanita javanica, Amanita esculenta, and Amanita similis, which were identified by sequence analysis of their rDNA internal transcribed spacer (ITS) region. Five selected isolates in A. caesareoides, A. javanica, and A. esculenta were tested for ectomycorrhizal syntheses with axenic Pinus densiflora seedlings in vitro. Ectomycorrhizal tips of each fungal isolate tested were observed on pine lateral roots within 5 months of inoculation. Seventeen pine seedlings that formed ectomycorrhizas in vitro with these three Amanita species were acclimatized under non-sterile conditions. Seven months following acclimatization, ectomycorrhizal colonization by A. caesareoides was observed on newly grown root tips, which was confirmed by polymerase chain reaction restriction fragment length polymorphism analysis of the fungal rDNA ITS region. Two other Amanita species also survived during ectomycorrhizal acclimatization. These results suggest that the cultivation of A. caesareoides and its relatives can be attempted through mycorrhizal synthesis using P. densiflora as a host. This is the first report of in vitro mycorrhization of Asian Caesar's mushrooms and their acclimatization under non-sterile conditions. PMID:23242587

Endo, Naoki; Gisusi, Seiki; Fukuda, Masaki; Yamada, Akiyoshi

2012-12-15

368

Permanent genetic resources added to Molecular Ecology Resources Database 1 October 2010-30 November 2010.  

PubMed

This article documents the addition of 277 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Ascochyta rabiei, Cambarellus chapalanus, Chionodraco hamatus, Coptis omeiensis, Cynoscion nebulosus, Daphnia magna, Gerbillus nigeriae, Isurus oxyrinchus, Lates calcarifer, Metacarcinus magister, Oplegnathus fasciatus, Pachycondyla verenae, Phaethon lepturus, Pimelodus grosskopfii, Rotylenchulus reniformis, Scomberomorus niphonius, Sepia esculenta, Terapon jarbua, Teratosphaeria cryptica and Thunnus obesus. These loci were cross-tested on the following species: Austropotamobius italicus, Cambarellus montezumae, Cambarellus puer, Cambarellus shufeldtii, Cambarellus texanus, Chionodraco myersi, Chionodraco rastrospinosus, Coptis chinensis, Coptis chinensis var. brevisepala, Coptis deltoidea, Coptis teeta, Orconectes virilis, Pacifastacus leniusculus, Pimelodus bochii, Procambarus clarkii, Pseudopimelodus bufonius, Rhamdia quelen, Sepia andreana, Sepiella maindroni, Thunnus alalunga, Thunnus albacares, Thunnus maccoyii, Thunnus orientalis, Thunnus thynnus and Thunnus tonggol. PMID:21429157

Agostini, Cecilia; Agudelo, P A; Bâ, K; Barber, P A; Bisol, Paolo Maria; Brouat, C; Burgess, Treena I; Calves, I; Carrillo Avila, Mauricio; Chow, S; Cordes, Lisa; Da Silva, D; Dalecky, A; De Meester, L; Doadrio, Ignacio; Dobigny, G; Duplantier, J M; Evison, Sophie E F; Ford, Rebecca; Fresneau, Dominique; Galetti, Pedro M; Gauthier, P; Geldof, S; Granjon, L; Guérin, F; St J Hardy, Giles E; Hernandez Escobar, Carlos; Hima, K; Hu, Juan; Huang, Luqi; Humeau, L; Jansen, B; Jaquemet, S; Jiang, Zhi-Qiang; Jung, Sung-Ju; Kim, Bong-Seok; Kim, Cheol-Hee; Kim, Jong-Oh; Lai, Choay-Hoong; Laroche, J; Lavergne, E; Lawton-Rauh, A; Le Corre, M; Leach, M M; Lee, Jehee; Leo, Audrey E; Lichtenzveig, Judith; Lin, Lin; Linde, Celeste C; Liu, Shu-Fang; Marino, Ilaria A M; McKeown, Niall J; Nohara, K; Oh, Myung-Joo; Okamoto, H; Oliver, Richard; Olivera Angel, Martha; Ornelas-García, Claudia Patricia; Orsini, L; Ostos Alfonso, Henry; Othman, A S; Papetti, Chiara; Patarnello, Tomaso; Pedraza-Lara, Carlos; Piller, Kyle R; Poteaux, Chantal; Requier, J-B; Roziana, M K; Semba, Y; Sembene, M; Shah, Ramisah M; Shahril, A R; Shao, Aijuan; Shaw, Paul W; Song, Liangke; Souza Ferreira, Ronara; Su, Yong-Quan; Suzuki, N; Tatard, C; Taylor, Katherine M; Taylor, Paul W J; Thiam, M; Valbuena, Ruben; Wang, He; Yang, Byung-Gyoo; Yuan, Qingjun; Zajonz, U; Zane, Lorenzo; Zhu, Ling; Zhuang, Zhi-Meng; Zulaiha, A R

2011-01-21

369

[Trematodes (trematoda) of amphibia from the Middle Volga region. 1. Orders Fasciolida, Hemiurida, Paramphistomida and Strigeida].  

PubMed

Data on trematodes of the orders Fasciolida, Hemiurida, Paramphistomida and Strigeida from 11 amphibian species of the Middle Volga region are given. Literature data for the last 30 years are reviewed for the first time; these data are supplemented by our own material. Reliable recordings are confirmed for 23 trematode species. Two of these species are new for amphibian trematode fauna of Russia. New hosts were revealed for 12 trematode species. Trematodes of the new for the region amphibian species, the edible frog Rana esculenta Linnaeus, 1758, are recorded for the first time. Two trematodes from freshwater fishes are shown to be temporary or occasional parasites of amphibians. The following characteristics are given for each parasite: it's systematic position, the spectrum of hosts, localization, collecting site, biology, geographical range, and the degree of host specificity. The morphological description and original figures are given for 9 species of parasites. PMID:23082495

Chikhliaev, I V; Kirillov, A A; Kirillova, N Iu

370

[Trematodes (Trematoda) of amphibia from the Middle Volga region. Report 2. Order Plagiorchiida].  

PubMed

Data on trematodes of the order Plagiorchiida from 11 species of amphibians from the Middle Volga region are given. Literary data of the last 30 years, combined with the results of our own research are presented together for the first time. Finds of 17 trematode species are reliable. From them, metacercaria of Astiotrema monticelli is recorded from amphibians of the fauna of Russia for the first time; Dolichosaccus rastellus and Paralepoderma cloacicola are recorded for the first time from amphibians of the Middle Volga region. New hosts are mentioned for 8 species of parasites. Trematodes of edible frog Rana esculenta Linnaeus, 1758, a new species to the region, are described for the first time. The following characteristics are given for each trematode species: its taxonomic position, set of hosts, localization, places of detection, biology, geographical distribution, and the degree of host specificity. Morphological descriptions and original figures are given for 12 trematode species. PMID:23285742

Chikhliaeva, I V; Kirillov, A A; Kirillova, N Iu

371

Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro  

SciTech Connect

Oxymorphazone was found to be a relatively weak antinociceptive drug in intact frog (Rana esculenta) when acetic acid was used as pain stimulus. Frogs remained analgesic for at least 48 hrs following oxymorphazone administration. The ligand increased the latency of wiping reflex in spinal frogs too. There effects were blocked by naloxone. In equilibrium binding studies (/sup 3/H)oxymorphazone had high affinity to the opioid receptors of frog brain and spinal cord as well. Kinetic experiments show that only 25% of the bound (/sup 3/H)oxymorphazone is readily dissociable. Preincubation of the membranes with labeled oxymorphazone results in a washing resistant inhibition of the opioid binding sites. At least 70% of the (/sup 3/H)oxymorphazone specific binding is apparently irreversible after reaction at 5 nM ligand concentration, and this can be enhanced by a higher concentration of tritiated ligand.

Benyhe, S.; Hoffman, G.; Varga, E.; Hosztafi, S.; Toth, G.; Borsodi, A.; Wollemann, M.

1989-01-01

372

Bacterial Communities of Two Parthenogenetic Aphid Species Cocolonizing Two Host Plants across the Hawaiian Islands ?  

PubMed Central

Aphids (Hemiptera: Aphididae) have been the focus of several studies with respect to their interactions with inherited symbionts, but bacterial communities of most aphid species are still poorly characterized. In this research, we used bar-coded pyrosequencing to characterize bacterial communities in aphids. Specifically, we examined the diversity of bacteria in two obligately parthenogenetic aphid species (the melon aphid, Aphis gossypii, and the cardamom aphid, Pentalonia caladii) cocolonizing two plant species (taro, Colocasia esculenta, and ginger, Alpinia purpurata) across four Hawaiian Islands (Hawaii, Kauai, Maui, and Oahu). Results from this study revealed that heritable symbionts dominated the bacterial communities for both aphid species. The bacterial communities differed significantly between the two species, and A. gossypii harbored a more diverse bacterial community than P. caladii. The bacterial communities also differed across aphid populations sampled from the different islands; however, communities did not differ between aphids collected from the two host plants.

Jones, Ryan T.; Bressan, Alberto; Greenwell, April M.; Fierer, Noah

2011-01-01

373

Constructed wetland as an ecotechnological tool for pollution treatment for conservation of Ganga river.  

PubMed

With aim to develop an efficient and ecofriendly approach for on-site treatment of sewage, a sub-surface flow constructed wetland (CW) has been developed by raising potential aquatic macrophytes; Typha latifolia, Phragmites australis, Colocasia esculenta, Polygonum hydropiper, Alternanthera sessilis and Pistia stratoites in gravel as medium. Sewage treatment potential of CW was evaluated by varying retention time at three different stages of plant growth and stabilization. After 6months, monitoring of fully established CW indicated reduction of 90%, 65%, 78%, 84%, 76% and 86% of BOD, TSS, TDS, NO3-N, PO4-P and NH4-N, respectively in comparison to inlet after 36h of retention time. Sewage treatment through CW also resulted in reduction of heavy metal contents. Thus, CW proved an effective method for treatment of wastewater and may be developed along river Ganga stretch as an alternative technology. Treated water may be drained into river to check further deterioration of Ganga water quality. PMID:24080292

Rai, U N; Tripathi, R D; Singh, N K; Upadhyay, A K; Dwivedi, S; Shukla, M K; Mallick, S; Singh, S N; Nautiyal, C S

2013-09-11

374

An amphibian antimicrobial peptide variant expressed in Nicotiana tabacum confers resistance to phytopathogens.  

PubMed Central

Esculentin-1 is a 46-residue antimicrobial peptide present in skin secretions of Rana esculenta. It is effective against a wide variety of micro-organisms, including plant pathogens with negligible effects on eukaryotic cells. As a possible approach to enhance plant resistance, a DNA coding for esculentin-1, with the substitution Met-28Leu, was fused at the C-terminal end of the leader sequence of endopolygalacturonase-inhibiting protein, under the control of the cauliflower mosaic virus 35S promoter region, and introduced into Nicotiana tabacum. The antimicrobial peptide was isolated from the intercellular fluids of healthy leaves of transgenic plants, suggesting that it was properly processed, secreted outside cells and accumulated in the intercellular spaces. The morphology of transgenic plants was unaffected. Challenging these plants with bacterial or fungal phytopathogens demonstrated enhanced resistance up to the second generation. Moreover, transgenic plants displayed insecticidal properties.

Ponti, Donatella; Mangoni, M Luisa; Mignogna, Giuseppina; Simmaco, Maurizio; Barra, Donatella

2003-01-01

375

Studies on lectins. XL. O-glycosyl derivatives of Spheron in affinity chromatography of lectins.  

PubMed

Free monosaccharides can be used for direct glycosylation of Spheron, a spherical macroporous hydroxyalkyl methacrylate-ethylene dimethacrylate copolymer, in a reaction that proceeds at room temperature in dioxane medium under catalysis of dry HCl or BF3. Derivatives of L-fucose, D-galactose, D-glucose, D-mannose, N-acetyl-D-galactosamine and N-acetyl-D-glucosamine thus prepared from Spheron beads have been shown to be efficient affinity carriers in isolation of lectins from seeds of Canavalia ensiformis D.C. (concanavalin A), Dolichos biflorus L., Glycine soja (L.) Sieb. et Zucc., Lens esculenta Moench, Ricinus communis L., Ulex europaeus L. and from albumin glands of the garden snail Helix pomatia L. PMID:638203

Filka, K; Coupek, J; Kocourek, J

1978-04-01

376

Fluorine-tagged 5-hydroxytryptophan to investigate amino Acid metabolism in vivo.  

PubMed

Auxin a plant growth hormone, has a metabolic pathway that includes molecules and enzymes like those in animal brains. In this study, tomato plant seedlings (Lycopersicon esculenta) were used to investigate the fate of fluorine-tagged 5-hydroxytryptophan (PF-5-HTP) being developed for fluorine spectroscopy and imaging. Seedlings were treated with high or low concentrations of 5-HTP or PF-5-HTP and compared with controls. Metabolites of the PF-5-HTP were quantified using a custom immunoassay for the tag. Serotonin (5-HT) levels were measured with spectrofluorometry and thin-layer chromatography. Plants in treatment conditions had serotonin levels five to six times higher than controls. PF-5-HTP served as a precursor for serotonin in a biosynthetic pathway in this plant model, providing evidence for the bioavailability of the novel molecule. The increase in serotonin in plants grown in media culture supplemented with 5-HTP or PF-5-HTP might have useful applications in pharmacology. PMID:22331995

Gagnon, Zofia E; Dingman, Sherry; Thomas, Rhys N

2010-05-19

377

Fluorine-Tagged 5-Hydroxytryptophan to Investigate Amino Acid Metabolism In Vivo  

PubMed Central

Auxin a plant growth hormone, has a metabolic pathway that includes molecules and enzymes like those in animal brains. In this study, tomato plant seedlings (Lycopersicon esculenta) were used to investigate the fate of fluorine-tagged 5-hydroxytryptophan (PF-5-HTP) being developed for fluorine spectroscopy and imaging. Seedlings were treated with high or low concentrations of 5-HTP or PF-5-HTP and compared with controls. Metabolites of the PF-5-HTP were quantified using a custom immunoassay for the tag. Serotonin (5-HT) levels were measured with spectrofluorometry and thin-layer chromatography. Plants in treatment conditions had serotonin levels five to six times higher than controls. PF-5-HTP served as a precursor for serotonin in a biosynthetic pathway in this plant model, providing evidence for the bioavailability of the novel molecule. The increase in serotonin in plants grown in media culture supplemented with 5-HTP or PF-5-HTP might have useful applications in pharmacology.

Gagnon, Zofia E.; Dingman, Sherry; Thomas, Rhys N.

2010-01-01

378

[The peripheral blood of frogs in the genus Rana as a test system for assessing environmental pollution].  

PubMed

Differential analysis of leukocytes was carried out peripheral blood smears of the frogs from four localities in the territory adjacent to a chemical plant in the Novgorod District (Rana temporaria) and two localities with an increased radiation background in the Bryansk District (R. lessonae and R. esculenta). Marked and similar changes in the content of neutrophilic and eosinophilic granulocytes were found in the frogs from all studied localities. A pronounced neutropenia was noted, which was often accompanied by the appearance of immature forms of the neutrophilic series. We propose that these changes are due selective damage of the entire series of differentiation of neutrophilic granulocytes, including the precursor cells. The increased percentage of eosinophilic granulocytes and appearance, in some cases, of immature cells are considered as signs of protective (antitoxic and antimicrobial) response. PMID:7987204

Chernyshova, E V; Starostin, V I

379

Antimicrobial and antioxidant activities of mycelia of 10 wild mushroom species.  

PubMed

Antimicrobial and antioxidant activities of mycelia obtained from 10 wild edible mushrooms-Armillaria mellea, Meripilus giganteus, Morchella costata, Morchella elata, Morchella esculenta var. vulgaris, Morchella hortensis, Morchella rotunda, Paxillus involutus, Pleurotus eryngii, and Pleurotus ostreatus-were investigated. For determination of antimicrobial activities of these mushrooms, ethanol extracts were examined with 11 test microorganisms by the agar well diffusion method. P. ostreatus and M. giganteus were the most active species against both bacteria and yeast. Antioxidant properties of ethanol extracts were studied by the 1,1-diphenyl-2-picrylhydrazyl free radical scavenging method. Among the mushroom extracts, M. elata showed the most potent radical scavenging activity. This research has shown that these 10 wild macrofungi have potential as natural antioxidants and antibiotics. PMID:20192845

Kalyoncu, Fatih; Oskay, Mustafa; Sa?lam, Hüsniye; Erdo?an, Tu?çe Fafal; Tamer, A Usame

2010-04-01

380

Floral thermogenesis of three species of Hydnora (Hydnoraceae) in Africa  

PubMed Central

Background and Aims Floral thermogenesis occurs in at least 12 families of ancient seed plants. Some species show very high rates of respiration through the alternative pathway, and some are thermoregulatory, with increasing respiration at decreasing ambient temperature. This study assesses the intensity and regulation of respiration in three species of African Hydnora that represent the Hydnoraceae, an unusual family of holoparasitic plants from arid environments. Methods Long-term respirometry (CO2 production) and thermometry were carried out on intact flowers of H. africana, H. abyssinica and H. esculenta in the field, and short-term measurements were made on floral parts during the protogynous flowering sequence. Key Results For H. africana, there was no temperature elevation in either the osmophores or the gynoecial chamber in any phase, and mass-specific respiration rates of the flower parts were low (maximum 8·3 nmol CO2 g?1 s?1 in osmophore tissue). Respiration tracked ambient and floral temperatures, eliminating the possibility of the inverse relationship expected in thermoregulatory flowers. Hydnora abyssinica flowers had higher respiration (maximum 27·5 nmol g?1 s?1 in the osmophores) and a slight elevation of osmophore temperature (maximum 2·8 °C) in the female stage. Respiration by gynoecial tissue was similar to that of osmophores in both species, but there was no measurable elevation of gynoecial chamber temperature. Gynoecial chamber temperature of H. esculenta could reach 3·8 °C above ambient, but there are no respiration data available. Antheral tissue respiration was maximal in the male phase (4·8 nmol g?1 s?1 in H. africana and 10·3 nmol g?1 s?1 in H. abyssinica), but it did not raise the antheral ring temperature, which showed that thermogenesis is not a by-product of pollen maturation or release. Conclusions The exceptionally low thermogenesis in Hydnora appears to be associated with scent production and possibly gynoecial development, but has little direct benefit to beetle pollinators.

Seymour, Roger S.; Maass, Erika; Bolin, Jay F.

2009-01-01

381

Distribution of mRNA encoding the FA-CHIP water channel in amphibian tissues: effects of salt adaptation.  

PubMed

A water channel, the frog aquaporin-CHIP (FA-CHIP) was recently cloned from Rana esculenta urinary bladder. The 28.9 kDa encoded protein shows 78.8%, 77.4%, 42.4% and 35.6% identity with rat CHIP28, human CHIP28, rat WCH-CD and gamma-TIP, other members of the new transmembrane water channel family (Aquaporin-CHIP). We have now studied membranes from different frog (R. esculenta) organs employing semiquantitative PCR using FA-CHIP specific primers and an internal standard to quantify the PCR products. The FA-CHIP mRNA was abundantly expressed in the frog urinary bladder, skin, lung and gall bladder, while a lower expression was detected in the colon, liver and oviduct. FA-CHIP mRNA was not detected in the frog kidney, erythrocytes and brain but its expression was observed in the toad (Bufo arenarum) urinary bladder and skin, showing that FA-CHIP is probably a general amphibian water channel. Salt acclimation is known to increase the water permeability of frog and toad epithelia. We have now observed that salt acclimation for 1, 3, 4 or 5 days markedly increased skin and urinary bladder FA-CHIP mRNA expression. It is generally accepted that water permeability is controlled in these tissues by the rate of water channel transfer from subapical vesicles (aggrephores) to the apical membrane. Our results indicate that water permeability is also regulated at the level of the FA-CHIP transcription. PMID:7539499

Abrami, L; Capurro, C; Ibarra, C; Parisi, M; Buhler, J M; Ripoche, P

1995-02-01

382

Successful drilling of the first horizontal well in a mature field  

SciTech Connect

This paper discusses how the decision to drill the first horizontal well of a reservoir was taken, based on Production acceleration and the incremental economy of cash flow. The reservoir is located in the Guafita-Norto Field in Western Venezuela, contiguous to the La Yuca-Cano Limon Fields in Colombia. Guafita-Norte has 183 million stb of remaining oil reserves with 26 production wells on electrical submergible pumps. The STOIP of this under saturated reservoir (bubble point pressure is 36 psi) is 160 million stb with an initial GOR of 10 stf/stb, having a permeability between 1.5-12 darcies with a strong water drive, water coning and sanding problems due to fines migration. During 1995, it was decided to drill the first horizontal well in the reservoir based on a 3-D numerical simulation with radial flow (for water coning) and local grid refinement (for horizontal wells) coupled to an economic analysis. The simulation predetermines an initial production rate for a horizontal well 2.5 times greater than for a vertical one, and the incremental cash flow for the horizontal well is 4.5 MM$ larger for the vertical one in four (4) years, with a ROR of 200%. The horizontal well was drilled with oil-based mud to avoid hole collapse, and it was completed open hole with a single screen pack. The well is currently producing between 2000 and 3500 stb/d, clean, on natural flow. This study has clearly shown that the ultimate and decisive parameter to be weighed before undertaking this type of project, is the economic analysis, which must be performed as extensively as the technical analysis.

Marruffo, I.; Achong, C. [Corpoven, S.A., Puerto La Cruz, Anzoategui (Venezuela)

1996-08-01

383

Anti-sickling effect of dietary thiocyanate in prophylactic control of sickle cell anemia.  

PubMed

As a clinical entity, sickle cell anemia (SCA) is known to be relatively rarer in Africans than in the African-American population of the United States. Paradoxically, sickle cell trait (SCT), the non-anemic, heterozygous condition, is about three times more common among indigenous Africans than in African-Americans. The ratio of SCA to SCT is 1:50 for African-Americans, and less than 1:1,000 for tropical Africans. This etiological disparity is attributed to an anti-sickling agent, thiocyanate, (SCN-) found abundantly in staple African foods, such as the African yam (Dioscorea sp) and cassava (Manihot utilissima). Staple American foods have negligible SCN-concentrations. Nonstaple foods in the American diet, such as carrots, cabbage, and radishes, have SCN- levels far below the African yam and cassava. This finding explains the high incidence of SCA among African-Americans and its rarity in Africans.The author concludes that SCA is a congenital deficiency anemia, ameliorable by prophylactic diets of foods with high SCN- contents. Thus, "thiocyanate deficiency anemia" is nutritionally a more correct clinical status for those born with the homozygous sickle hemoglobin genome. Just as any iron undernourished person can suffer from iron deficiency anemia, sickle hemoglobin homozygotes suffer from "thiocyanate deficiency anemia" when they subsist on SCN-deficient foods. This article reviews the role of dietary SCN- in SCA control. PMID:3795284

Agbai, O

1986-11-01

384

Purification and properties of new ribosome-inactivating proteins with RNA N-glycosidase activity.  

PubMed

Ribosome-inactivating proteins (RIPs) similar to those already known (Stirpe & Barbieri (1986) FEBS Lett. 195, 1-8) were purified from the seeds of Asparagus officinalis (two proteins, asparin 1 and 2), of Citrullus colocynthis (two proteins, colocin 1 and 2), of Lychnis chalcedonica (lychnin) and of Manihot palmata (mapalmin), from the roots of Phytolacca americana (pokeweed antiviral protein from roots, PAP-R) and from the leaves of Bryonia dioica (bryodin-L). The two latter proteins can be considered as isoforms, respectively, of previously purified PAP, from the leaves of P. americana, and of bryodin-R, from the roots of B. dioica. All proteins have an Mr at approx, 30,000, and an alkaline isoelectric point. Bryodin-L, colocins, lychnin and mapalmin are glycoproteins. All RIPs inhibit protein synthesis by a rabbit reticulocyte lysate and phenylalanine polymerization by isolated ribosomes and alter rRNA in a similar manner as the A-chain of ricin and related toxins (Endo et al. (1987) J. Biol. Chem. 262, 5908-5912). PMID:2248976

Bolognesi, A; Barbieri, L; Abbondanza, A; Falasca, A I; Carnicelli, D; Battelli, M G; Stirpe, F

1990-11-30

385

Cassava; African perspective on space agriculture  

NASA Astrophysics Data System (ADS)

Looking on African perspective in space agriculture may contribute to increase diversity, and enforce robustness for advanced life support capability. Cassava, Manihot esculentaand, is one of major crop in Africa, and could be a candidate of space food materials. Since resource is limited for space agriculture in many aspects, crop yield should be high in efficiency, and robust as well. The efficiency is measured by farming space and time. Harvest yield of cassava is about 41 MJ/ m2 (70 ton/ha) after 11 months of farming. Among rice, wheat, potato, and sweet potato, cassava is ranked to the first place (40 m2 ) in terms of farming area required to supply energy of 5 MJ/day, which is recommended for one person. Production of cassava could be made under poor condition, such as acidic soil, shortage of fertilizer, draught. Laterite, similar to Martian regolith. Propagation made by stem cutting is an advantage of cassava in space agriculture avoiding entomophilous or anemophilous process to pollinate. Feature of crop storage capability is additional factor that determines the efficiency in the whole process of agriculture. Cassava root tuber can be left in soil until its consumption. Cassava might be an African contribution to space agriculture.

Katayama, Naomi; Njemanze, Philip; Nweke, Felix; Space Agriculture Task Force, J.; Katayama, Naomi; Yamashita, Masamichi

386

Permanent Genetic Resources added to Molecular Ecology Resources Database 1 August 2009-30 September 2009.  

PubMed

This article documents the addition of 238 microsatellite marker loci and 72 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Adelges tsugae, Artemisia tridentata, Astroides calycularis, Azorella selago, Botryllus schlosseri, Botrylloides violaceus, Cardiocrinum cordatum var. glehnii, Campylopterus curvipennis, Colocasia esculenta, Cynomys ludovicianus, Cynomys leucurus, Cynomys gunnisoni, Epinephelus coioides, Eunicella singularis, Gammarus pulex, Homoeosoma nebulella, Hyla squirella, Lateolabrax japonicus, Mastomys erythroleucus, Pararge aegeria, Pardosa sierra, Phoenicopterus ruber ruber and Silene latifolia. These loci were cross-tested on the following species: Adelges abietis, Adelges cooleyi, Adelges piceae, Pineus pini, Pineus strobi, Tubastrea micrantha, three other Tubastrea species, Botrylloides fuscus, Botrylloides simodensis, Campylopterus hemileucurus, Campylopterus rufus, Campylopterus largipennis, Campylopterus villaviscensio, Phaethornis longuemareus, Florisuga mellivora, Lampornis amethystinus, Amazilia cyanocephala, Archilochus colubris, Epinephelus lanceolatus, Epinephelus fuscoguttatus, Symbiodinium temperate-A clade, Gammarus fossarum, Gammarus roeselii, Dikerogammarus villosus and Limnomysis benedeni. This article also documents the addition of 72 sequencing primer pairs and 52 allele specific primers for Neophocaena phocaenoides. PMID:21565018

Abdoullaye, Doukary; Acevedo, I; Adebayo, Abisola A; Behrmann-Godel, Jasminca; Benjamin, R C; Bock, Dan G; Born, Céline; Brouat, Carine; Caccone, Adalgisa; Cao, Ling-Zhen; Casado-Amezúa, P; Catanéo, J; Correa-Ramirez, M M; Cristescu, Melania E; Dobigny, Gauthier; Egbosimba, Emmanuel E; Etchberger, Lianna K; Fan, Bin; Fields, Peter D; Forcioli, D; Furla, P; Garcia de Leon, F J; García-Jiménez, R; Gauthier, Philippe; Gergs, René; González, Clementina; Granjon, Laurent; Gutiérrez-Rodríguez, Carla; Havill, Nathan P; Helsen, P; Hether, Tyler D; Hoffman, Eric A; Hu, Xiangyang; Ingvarsson, Pär K; Ishizaki, S; Ji, Heyi; Ji, X S; Jimenez, M L; Kapil, R; Karban, R; Keller, Stephen R; Kubota, S; Li, Shuzhen; Li, Wansha; Lim, Douglas D; Lin, Haoran; Liu, Xiaochun; Luo, Yayan; Machordom, A; Martin, Andrew P; Matthysen, E; Mazzella, Maxwell N; McGeoch, Mélodie A; Meng, Zining; Nishizawa, M; O'Brien, Patricia; Ohara, M; Ornelas, Juan Francisco; Ortu, M F; Pedersen, Amy B; Preston, L; Ren, Qin; Rothhaupt, Karl-Otto; Sackett, Loren C; Sang, Qing; Sawyer, G M; Shiojiri, K; Taylor, Douglas R; Van Dongen, S; Van Vuuren, Bettine Jansen; Vandewoestijne, S; Wang, H; Wang, J T; Wang, L E; Xu, Xiang-Li; Yang, Guang; Yang, Yongping; Zeng, Y Q; Zhang, Qing-Wen; Zhang, Yongping; Zhao, Y; Zhou, Yan

2010-01-01

387

Analytical characterization of beet root vacuole membrane  

SciTech Connect

Vacuoles from beet root (Beta vulgaris L. var. esculenta Gurke) isolated by a mechanical procedure were osmotically lysed to separate the membrane and sap components for analysis. Approximately 62% of the vacuole proteins, 70% of the nondialyzable carbohydrates and almost all of the phospholipids and sterols were recovered in the membrane fraction. The vacuole membrane had a phospholipid:protein ratio of 0.68 and a sterol:phospholipid ratio of 0.21. Seventeen complex polar lipids including phosphatides ad glycolipids have been tentatively identified. Phosphatidylcholine (54%) and phosphatidylethanolamine (24%) were the most prominant phosphoglycerides besides phosphatidylserine, phosphatidylglycerol, phosphatidylinositol, and phosphatidic acid (1, 4, 5, and 12%, respectively. A putative sulfoglycoside and two major ceramide glycoside-like lipids, resembling those of animal lysosomes, were identified by thin-layer chromatography. High-resolution SDS-acrylamide gel electrophoresis of the polypeptides from the vacuole revealed 15 major bands with apparent molecular weights ranging from 91,000 to 12,000. Selective elution experiments delineated those polypeptides that were peripheral membrane proteins or sap proteins adsorbed to the membrane, and those that exhibited hydrophobic interaction with the lipid core. Lectin labeling results indicated that most of the polypeptides from the membrane and from the sap were glycoproteins probably of the high-mannose type characteristic of lysosomal enzymes that have undergone several stages of posttranslational modification.

Marty, F.; Branton, D.

1980-10-01

388

Localization, Concentration, and Transmission Efficiency of Banana bunchy top virus in Four Asexual Lineages of Pentalonia aphids  

PubMed Central

Banana bunchy top virus (BBTV) is the most destructive pathogenic virus of banana plants worldwide. The virus is transmitted in a circulative non-propagative manner by the banana aphid, Pentalonia nigronervosa Coquerel. In this work, we examined the localization, accumulation, and transmission efficiency of BBTV in four laboratory-established lineages of Pentalonia aphids derived from four different host plants: taro (Colocasia esculenta), heliconia (Heliconia spp.), red ginger (Alpinia purpurata), and banana (Musa sp.). Mitochondrial sequencing identified three and one lineages as Pentalonia caladii van der Goot, a recently proposed species, and P. nigronervosa, respectively. Microsatellite analysis separated the aphid lineages into four distinct genotypes. The transmission of BBTV was tested using leaf disk and whole-plant assays, both of which showed that all four lineages are competent vectors of BBTV, although the P. caladii from heliconia transmitted BBTV to the leaf disks at a significantly lower rate than did P. nigronervosa. The concentration of BBTV in dissected guts, haemolymph, and salivary glands was quantified by real-time PCR. The BBTV titer reached similar concentrations in the guts, haemolymph, and salivary glands of aphids from all four lineages tested. Furthermore, immunofluorescence assays showed that BBTV antigens localized to the anterior midguts and the principal salivary glands, demonstrating a similar pattern of translocations across the four lineages. The results reported in this study showed for the first time that P. caladii is a competent vector of BBTV.

Watanabe, Shizu; Greenwell, April M.; Bressan, Alberto

2013-01-01

389

Multi-host ectomycorrhizal fungi are predominant in a Guinean tropical rainforest and shared between canopy trees and seedlings.  

PubMed

The diversity of ectomycorrhizal (ECM) fungi on adult trees and seedlings of five species, Anthonotha fragrans, Anthonotha macrophylla, Cryptosepalum tetraphyllum, Paramacrolobium coeruleum and Uapaca esculenta, was determined in a tropical rain forest of Guinea. Ectomycorrhizae were sampled within a surface area of 1600 m(2), and fungal taxa were identified by sequencing the rDNA Internal Transcribed Spacer region. Thirty-nine ECM fungal taxa were determined, of which 19 multi-hosts, 9 single-hosts and 11 singletons. The multi-host fungi represented 92% (89% when including the singletons in the analysis) of the total abundance. Except for A. fragrans, the adults of the host species displayed significant differentiation for their fungal communities, but their seedlings harboured a similar fungal community. These findings suggest that there was a potential for the formation of common mycorrhizal networks in close vicinity. However, no significant difference was detected for the ?(13)C and ?(15)N values between seedlings and adults of each ECM plant, and no ECM species exhibited signatures of mixotrophy. Our results revealed (i) variation in ECM fungal diversity according to the seedling versus adult development stage of trees and (ii) low host specificity of ECM fungi, and indicated that multi-host fungi are more abundant than single-host fungi in this forest stand. PMID:21966915

Diédhiou, Abdala Gamby; Selosse, Marc-André; Galiana, Antoine; Diabaté, Moussa; Dreyfus, Bernard; Bâ, Amadou Moustapha; De Faria, Sergio Miana; Béna, Gilles

2010-03-03

390

Effect of Temperature on Starch Synthesis in Potato Tuber Tissue and in Amyloplasts  

PubMed Central

A sharp temperature optimum is observed at 21.5°C when the incorporation of [14C]sucrose into starch is measured with discs cut from developing tubers of potato (Solanum tuberosum L. cv Desirée). By contrast, increasing temperatures over the range 9 to 31°C only enhance release of 14C to respiratory CO2 and incorporation of 14C into the ethanolsoluble fraction. By comparison, starch synthesis in discs from developing corms of cocoyam (Colocasia esculenta L. Schott) is increased by raising the temperature from 15 to 35°C. The significance of a relatively low temperature optimum for starch synthesis in potato is discussed in relation to the yield limitations imposed by continuously high soil temperatures. Amyloplasts isolated from protoplasts prepared from developing potato tubers contain activities of alkaline pyrophosphatase, NAD-dependent glyceraldehyde-3-phosphate dehydrogenase, fructose-1,6-bisphosphatase, and phosphoglucomutase in addition to ADP-glucose-pyrophosphorylase, starch phosphorylase and starch synthase. Cell-free amyloplasts released by thinly slicing developing potato tubers synthesize starch from [14C]triose-phosphate generated from [14C]fructose-1,6-bisphosphate in the reaction medium. This starch synthesis is inhibited by addition of 10 millimolar inorganic phosphate and requires amyloplast integrity, suggesting the operation of a triose-phosphate/inorganic phosphate exchange carrier at the amyloplast membrane. The temperature optimum at 21.5°C observed with tissue discs is not observed with amyloplasts.

Mohabir, Gangaram; John, Philip

1988-01-01

391

Invariants in the ipsilateral retinotectal visual projection of frogs.  

PubMed

We determined whether the sensitivity of the ipsilateral type II units of Rana esculenta to prey (W/H-oriented bars) and non-prey (A/V-oriented bars)-like targets remains invariant under various experimental conditions. We show that the shape of the 'discrimination' curve is largely unaffected by the level of general illumination and by the background texture. An increase in the stimulus velocity and in the width of the bars moderately affects the salient points (negative peak and preference reversal) of the curve, but does not alter the overall configurational preference of these units. As for retinal ganglion cells: (i) this curve expresses better a 'contrast' between two vertically oriented edges of different dimensions than a 'contrast' between two edges of equal dimension but of different orientation; and (ii) the experimentally induced variations can be explained on the basis of the spatial and temporal properties of the neuronal elements forming the antagonistic center-surround arrangement of the receptive field. PMID:10216935

Beauquin, C; Gaillard, F

1999-01-01

392

Reclassification of Rhizobium tropici type A strains as Rhizobium leucaenae sp. nov.  

PubMed

Rhizobium tropici is a well-studied legume symbiont characterized by high genetic stability of the symbiotic plasmid and tolerance to tropical environmental stresses such as high temperature and low soil pH. However, high phenetic and genetic variabilities among R. tropici strains have been largely reported, with two subgroups, designated type A and B, already defined within the species. A polyphasic study comprising multilocus sequence analysis, phenotypic and genotypic characterizations, including DNA-DNA hybridization, strongly supported the reclassification of R. tropici type A strains as a novel species. Type A strains formed a well-differentiated clade that grouped with R. tropici, Rhizobium multihospitium, Rhizobium miluonense, Rhizobium lusitanum and Rhizobium rhizogenes in the phylogenies of the 16S rRNA, recA, gltA, rpoA, glnII and rpoB genes. Several phenotypic traits differentiated type A strains from all related taxa. The novel species, for which the name Rhizobium leucaenae sp. nov. is proposed, is a broad host range rhizobium being able to establish effective root-nodule symbioses with Leucaena leucocephala, Leucaena esculenta, common beans (Phaseolus vulgaris) and Gliricidia sepium. Strain CFN 299(T) (?=?USDA 9039(T)?=?LMG 9517(T)?=?CECT 4844(T)?=?JCM 21088(T)?=?IAM 14230(T)?=?SEMIA 4083(T)?=?CENA 183(T)?=?UMR1026(T)?=?CNPSo 141(T)) is designated the type strain of Rhizobium leucaenae sp. nov. PMID:21742822

Ribeiro, Renan Augusto; Rogel, Marco A; López-López, Aline; Ormeño-Orrillo, Ernesto; Barcellos, Fernando Gomes; Martínez, Julio; Thompson, Fabiano Lopes; Martínez-Romero, Esperanza; Hungria, Mariangela

2011-07-08

393

Availability of in vitro vitellogenin assay for screening of estrogenic and anti-estrogenic activities of environmental chemicals.  

PubMed

Vitellogenin (VTG) protein, VTG mRNA, other egg yolk proteins, vitelline envelope proteins and their mRNAs are produced in the liver of oviparous species by stimulation of endogenous estrogen and exogenous estrogenic chemicals. The VTG assay based on enzyme-linked immunosorbent assay (ELISA) has been widely used for many fish species to screen estrogenic and anti-estrogenic activities of chemicals and sewage effluents using immature fish and/or male fish. In order to reduce the number of fish for screening of estrogenicity and anti-estrogenicity of chemicals, primary cultured fish hepatocytes can be used. In fact, primary cultured hepatocytes have been successfully used for the detection of estrogenic and anti-estrogenic activities of environmental chemicals in selected OECD fish species, e.g., medaka (Oryzias latipes) and rainbow trout (Oncorhynchys mykiss) together with other fish species such as Atlantic salmon (Salmo salar L.), Siberian sturgeon (Acipenser baeri), tilapia (Oreochromis mossambicus), carp (Cyprinus carpio), bream (Abramis brama), Carassius auratus, silver eel (Anguilla anguilla L.), and channel catfish (Ictalurus punctanus). In terms of hepatocyte assays relating to other taxa, these include frogs such as Xenopus laevis and the common green frog (Rana esculenta), chickens (Gallus domesticus) and herring gulls (Larus argentatus). VTG mRNA measurement by quantitative reverse transcription-polymerase chain reaction has also been successfully applied in the primary cultured hepatocytes of various species. PMID:16883298

Iguchi, Taisen; Irie, Fumi; Urushitani, Hiroshi; Tooi, Osamu; Kawashima, Yukio; Roberts, Mike; Norrgren, Leif; Hutchinson, Thomas

2006-01-01

394

Lipovitellin-phosvitin crystals with orthorhombic features: thin-section electron microscopy, gel electrophoresis, and microanalysis in teleost and amphibian yolk platelets and a comparison with other vertebrates.  

PubMed

Yolk-platelet crystals in the teleosts Pelvicachromis pulcher and Noemacheilus barbatulus and the amphibians Xenopus laevis, Rana temporaria, R. esculenta, and Triturus sp. have been studied by electron diffraction and imaging using a standardized processing (glutaraldehyde-osmium tetroxide fixation, glutaraldehyde-urea embedding, thin-section staining), by X-ray microanalysis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of their constituents. The crystal lattice is orthorhombic having--following standardized processing--in three amphibians a = 9.0 nm, b = 17.6 nm, c = 19.2 nm, and in the two teleosts a = 8.9 nm, b = 17.6 nm, c = 20.0 nm (averages). These values are very close to X-ray data from wet crystals (Xenopus laevis). Crystal images in the three axial projections point to the presence of space group P212121 (or an approximation of it since the lipovitellin dimers cannot be fully equivalent in some cases), to differences between the phosvitins of the two teleosts, and to a highly unusual stain exclusion from large crystal constituents interpreted as representing lipovitellin dimers. Microanalysis in ultrathin cryosections and other preparations revealed K and Cl to be the prominent ions in the crystals (and in the superficial layer of the platelet). Gel electrophoresis (including data of cyclostomes) showed considerable molecular variations despite a closely similar crystal architecture, emphasizing a physiological significance of the architecture, which may have remained conserved for nearly 400 million years according to paleontologic views. PMID:6602894

Lange, R H; Richter, H P; Riehl, R; Zierold, K; Trandaburu, T; Magdowski, G

1983-05-01

395

Propulsive force calculations in swimming frogs. II. Application of a vortex ring model to DPIV data.  

PubMed

Frogs propel themselves by kicking water backwards using a synchronised extension of their hind limbs and webbed feet. To understand this propulsion process, we quantified the water movements and displacements resulting from swimming in the green frog Rana esculenta, applying digital particle image velocimetry (DPIV) to the frog's wake. The wake showed two vortex rings left behind by the two feet. The rings appeared to be elliptic in planform, urging for correction of the observed ring radii. The rings' long and short axes (average ratio 1.75:1) were about the same size as the length and width of the propelling frog foot and the ellipsoid mass of water accelerated with it. Average thrust forces were derived from the vortex rings, assuming all propulsive energy to be compiled in the rings. The calculated average forces (F(av)=0.10+/-0.04 N) were in close agreement with our parallel study applying a momentum-impulse approach to water displacements during the leg extension phase. We did not find any support for previously assumed propulsion enhancement mechanisms. The feet do not clap together at the end of the power stroke and no "wedge-action" jetting is observed. Each foot accelerates its own water mantle, ending up in a separate vortex ring without interference by the other leg. PMID:15802668

Stamhuis, Eize J; Nauwelaerts, Sandra

2005-04-01

396

The Medicinal Uses of Poi  

PubMed Central

Poi is a pasty starch made from the cooked, mashed corm of the taro plant (Colocasia esculenta L.). Originating in Asia, this root crop is now found primarily in tropical and subtropical regions and was a major dietary staple in the Pacific islands. We hypothesize that poi has potential use as a probiotic—defined by FAO/WHO as, “live microorganisms which when administered in adequate amounts confer a health benefit to the host.” No scientific studies have explored the possibility of poi being used as a probiotic in medical nutrition therapy, however, an investigator determined that the predominant bacteria in poi are Lactococcus lactis (95%) and Lactobacilli (5%), both of which are lactic acid-producing bacteria. This investigator also reported that poi contains significantly more of these bacteria per gram than yogurt. To determine if poi is beneficial for certain health conditions, a literature search was conducted to find all available research studies in which poi was used as a complementary treatment. Documented evidence suggests that poi shows promise for use in infants with allergies or failure-to-thrive. However, to support previous findings, more research needs to be conducted with poi and its potential use as a probiotic.

Brown, Amy C.; Valiere, Ana

2006-01-01

397

Heat and mass transfer in deep-frying of pumpkin, sweet potato and taro.  

PubMed

Heat and mass transfer parameters, effective thermal diffusivity, heat transfer coefficient, effective moisture diffusivity and moisture transfer coefficient-for pumpkin (Cucurbita pepo), sweet potato (Ipomoea batatas) and taro (Colocasia esculenta) under deep-frying conditions were determined by fitting experimental data on transient values of temperature and moisture content to the solution of the standard diffusion equation in cylindrical coordinates as modified by Dincer (Heat Mass Transfer 32:109-113, 1996). A case of Biot number in the range of 0< B i <100 was considered in this study. Remarkably good agreement was found between estimated and calculated values as the root mean square error between the measured and calculated temperature and moisture content values were only 5.0% and 1.3%, respectively. The model can be easily and effectively used to determine effective diffusion coefficients as well as transfer coefficients for heat and mass transfer. The oil uptake values for the above vegetables were lower than the values reported for other deep fried products. PMID:23572697

Ahromrit, Araya; Nema, Prabhat K

2010-10-08

398

Trichoderma gamsii (NFCCI 2177): A newly isolated endophytic, psychrotolerant, plant growth promoting, and antagonistic fungal strain.  

PubMed

An endophytic fungus has been isolated from the lateral roots of lentil (Lens esculenta Moench), growing under mountain ecosystem of Indian Himalayan Region (IHR). While the fungus was observed as fast growing with white scanty mycelium turning to turmeric brown in 5 days of incubation at 25?°C, it also produced a unique odor. The fungus exhibited growth between 4 and 30?°C (optimum 25?°C) and tolerated pH between 2.0 and 13.5 (optimum 4-6). Based on phenotypic (colony morphology and microscopy) and genotypic (18S rRNA analysis) characters, the fungus was identified as Trichoderma gamsii (99% similarity). The fungus was evaluated for its plant growth promotion and biocontrol properties. The fungus was found to be positive for phosphate solubilization, chitinase activity, and production of ammonia and salicylic acid, while the results for production of IAA, HCN, and siderophores were negative. Out of the seven phytopathogenic fungi tested, it showed antagonism against six. Bioassays conducted under green house using four test crops (two cereals and two legumes) showed its potential in plant growth promotion. The fungus has potential to be developed as a bioformulation for application under mountain ecosystem. PMID:23564225

Rinu, K; Sati, Priyanka; Pandey, Anita

2013-04-01

399

Zoospores of three Arctic laminariales under different UV radiation and temperature conditions: exceptional spectral absorbance properties and lack of phlorotannin induction.  

PubMed

Phlorotannins have often been considered to act as UV-protective compounds in zoospores of brown algae. However, only the absorption characteristics of zoospores under UV exposure have been determined and no data are available on the actual content of phlorotannins or on temperature-UV interactions. Therefore, we determined the absorbance spectra and the phlorotannin contents in zoospore suspensions of three Arctic species (Saccharina latissima, Laminaria digitata, Alaria esculenta), and in the media surrounding zoospores after exposure to different radiation (400-700, 320-700, 295-700 nm) and temperature (2-18 degrees C) conditions for 8 h. Absorption typical of phlorotannins with a maximum at 276 nm was monitored in zoospore suspensions as well as in the media surrounding zoospores, but the results depended strongly on radiation treatments and on zoospore densities. Surprisingly, the content of UV-absorbing phlorotannins subsequent to different exposures did not change in any of the three species. The observed exceptional absorption properties could, therefore, not be related to phlorotannin contents. These findings are discussed in light of a strong phlorotannin investment from sporophytes during spore release and a minor UV-protective role of phlorotannins for zoospores of Arctic kelp species. PMID:19175751

Müller, Ruth; Wiencke, Christian; Bischof, Kai; Krock, Bernd

2009-01-23

400

Numerical analysis and the application of random amplified polymorphic DNA polymerase chain reaction to the differentiation of Vibrio strains from a seasonally cold ocean.  

PubMed

Eighty regional strains of Vibrio isolated from the seasonally cold waters of coastal Newfoundland, and a number of Vibrio reference cultures, were studied. The regional strains had been isolated from the brown macroalga Alaria esculenta and the giant scallop Placopecten magellanicus and were known to grow at 4 degrees C. The strains were grouped according to their arginine-dihydrolase reactions and examined by numerical analysis. According to phenotypic properties the arginine-dihydrolase positive strains closely resembled Vibrio splendidus biovar I. Most clusters of the arginine-dihydrolase negative strains appeared to be unique but the closest phenotypic resemblance among some strains was with Vibrio ordalii. Some strains were examined using the random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) technique for fingerprinting and it was shown that the regional strains were significantly different from either V. splendidus biovar I or V. ordalii. Generally, the strains from seaweed clustered separately from those that were from scallops. Strains in some clusters, especially those from the seaweed, were able to utilize most of the compounds that were tested as sole sources of carbon and energy. PMID:8050065

Martin-Kearley, J; Gow, J A; Péloquin, M; Greer, C W

1994-06-01

401

Studies on algal cytochromes. III. Amino acid sequence of cytochrome c-553 from a brown alga, Petalonia fascia.  

PubMed

The amino acid sequence of a photosynthetic cytochrome c-553 isolated from a brown alga, Petalonia fascia was determined by BrCN fragmentation and a solid phase Edman degradation. The cytochrome contains 85 amino acid residues, giving a molecular weight of 9,803. The complete amino acid sequence is as follows: Val-Asp-Ile-Asn-Asn-Gly-Glu-Ser-Val-Phe-Thr-Ala-Asn-Cys-Ser-Ala-Cys-His-Ala-Gly -Gly-Asn-Asn-Val-Ile-Met-Pro-Glu-Lys-Thr-Leu-Lys-Lys-Asp-Ala-Leu-Glu-Glu-Asn-Gl u-Met-Asn-Asn-Ile-Lys-Ser-Ile-Thr-Tyr-Gln-Val-Thr-Asn-Gly-Lys-Asn-Ala-Met-Pro-A la-Phe-Gly-Gly-Arg-Leu-Ser-Glu-Thr-Asp-Ile-Glu-Asp-Val-Ala-Asn-Phe-Val-Ile-Ser-Gln-Ser-Gln-Lys-Gly-Trp. The highest homology was found between the sequences of cytochromes c-553 of P. fascia and Alaria esculenta, the next between those of P. fascia and Porphyria tenera. PMID:6273394

Sugimura, Y; Hase, T; Matsubara, H; Shimokoriyama, M

1981-10-01

402

Seaweed and soy: companion foods in Asian cuisine and their effects on thyroid function in American women.  

PubMed

Seaweeds and soy are two commonly eaten foods in Asia. Both have been reported to affect thyroid function, seaweed because of its iodine content and soy because of its goitrogenic effect. Twenty-five healthy postmenopausal women (mean age 58 years) completed a double-blinded randomized crossover study. Ten capsules (5 g/day) of placebo or seaweed (Alaria esculenta), providing 475 microg of iodine/day, were consumed daily for 7 weeks. A powdered soy protein isolate (Solae Co., St. Louis, MO), providing 2 mg of isoflavones/kg of body weight, was given daily during the last week of each treatment arm. On average, this provided 141.3 mg of isoflavones/day and 67.5 g of protein/day. Blood samples and 48-hour urine samples were collected before and after each intervention period, and urinary I/C (microg of iodine/g of creatinine) and serum thyroxine, free thyroxine index, total triiodothyronine, and thyroid stimulating hormone (TSH) were measured. Seaweed ingestion increased I/C concentrations (P < .0001) and serum TSH (P < .0001) (1.69 +/- 0.22 vs. 2.19 +/- 0.22 microU/mL, mean +/- SE). Soy supplementation did not affect thyroid end points. Seven weeks of 5 g/day seaweed supplementation was associated with a small but statistically significant increase in TSH. Soy protein isolate supplementation was not associated with changes in serum thyroid hormone concentrations. PMID:17472472

Teas, Jane; Braverman, Lewis E; Kurzer, Mindy S; Pino, Sam; Hurley, Thomas G; Hebert, James R

2007-03-01

403

Localization, concentration, and transmission efficiency of Banana bunchy top virus in four asexual lineages of Pentalonia aphids.  

PubMed

Banana bunchy top virus (BBTV) is the most destructive pathogenic virus of banana plants worldwide. The virus is transmitted in a circulative non-propagative manner by the banana aphid, Pentalonia nigronervosa Coquerel. In this work, we examined the localization, accumulation, and transmission efficiency of BBTV in four laboratory-established lineages of Pentalonia aphids derived from four different host plants: taro (Colocasia esculenta), heliconia (Heliconia spp.), red ginger (Alpinia purpurata), and banana (Musa sp.). Mitochondrial sequencing identified three and one lineages as Pentalonia caladii van der Goot, a recently proposed species, and P. nigronervosa, respectively. Microsatellite analysis separated the aphid lineages into four distinct genotypes. The transmission of BBTV was tested using leaf disk and whole-plant assays, both of which showed that all four lineages are competent vectors of BBTV, although the P. caladii from heliconia transmitted BBTV to the leaf disks at a significantly lower rate than did P. nigronervosa. The concentration of BBTV in dissected guts, haemolymph, and salivary glands was quantified by real-time PCR. The BBTV titer reached similar concentrations in the guts, haemolymph, and salivary glands of aphids from all four lineages tested. Furthermore, immunofluorescence assays showed that BBTV antigens localized to the anterior midguts and the principal salivary glands, demonstrating a similar pattern of translocations across the four lineages. The results reported in this study showed for the first time that P. caladii is a competent vector of BBTV. PMID:23435241

Watanabe, Shizu; Greenwell, April M; Bressan, Alberto

2013-02-22

404

Bioremediation and Detoxification of Synthetic Wastewater Containing Triarylmethane Dyes by Aeromonas hydrophila Isolated from Industrial Effluent.  

PubMed

Economical and bio-friendly approaches are needed to remediate dye-contaminated wastewater from various industries. In this study, a novel bacterial strain capable of decolorizing triarylmethane dyes was isolated from a textile wastewater treatment plant in Greece. The bacterial isolate was identified as Aeromonas hydrophila and was shown to decolorize three triarylmethane dyes tested within 24?h with color removal in the range of 72% to 96%. Decolorization efficiency of the bacterium was a function of operational parameters (aeration, dye concentration, temperature, and pH) and the optimal operational conditions obtained for decolorization of the dyes were: pH 7-8, 35°C and culture agitation. Effective color removal within 24?h was obtained at a maximum dye concentration of 50?mg/L. Dye decolorization was monitored using a scanning UV/visible spectrophotometer which indicated that decolorization was due to the degradation of dyes into non-colored intermediates. Phytotoxicity studies carried out using Triticum aestivum, Hordeum vulgare, and Lens esculenta revealed the triarylmethane dyes exerted toxic effects on plant growth parameters monitored. However, significant reduction in toxicity was obtained with the decolorized dye metabolites thus, indicating the detoxification of the dyes following degradation by Aeromonas hydrophila. PMID:21808740

Ogugbue, Chimezie Jason; Sawidis, Thomas

2011-07-25

405

Analytical characterization of beetroot vacuole membrane  

PubMed Central

Vacuoles from beetroot (Beta vulgaris L. var. esculenta Gurke) isolated by a mechanical procedure were osmotically lysed to separate the membrane and sap components for analysis. Approximately 62% of the vacuole proteins, 70% of the nondialyzable carbohydrates and almost all of the phospholipids and sterols were recovered in the membrane fraction. The vacuole membrane had a phospholipid protein ratio of 0.68 and a sterol:phospholipid ratio of 0.21. 17 complex polar lipids including phosphatides and glycolipids have been tentatively identified. Phosphatidylcholine (54%) and phosphatidylethanolamine (24%) were the most prominent phosphoglycerides besides phosphatidylserine, phosphatidylglycerol, phosphatidylinositol, and phosphatidic acid (1, 4, 5, and 12%, respectively). A putative sulfoglycoside and two major ceramide glycoside-like lipids, resembling those of animal lysosomes, were identified by thin-layer chromatography. High-resolution SDS-acrylamide gel electrophoresis of the polypeptides from the vacuole revealed 15 major bands with apparent molecular weights ranging from 91,000 to 12,000. Selective elution experiments delineated those polypeptides that were peripheral membrane proteins or sap proteins adsorbed to the membrane, and those that exhibited hydrophobic interactions with the lipid core. Lectin labeling results indicated that most of the polypeptides from the membrane and from the sap were glycoproteins probably of the high-mannose type characteristic of lysosomal enzymes that have undergone several stages of posttranslational modification.

1980-01-01

406

Natural interspecies transfer of mitochondrial DNA in amphibians.  

PubMed

mtDNAs of two Central European water frog species, Rana ridibunda and Rana lessonae, were examined by electrophoresis of restriction enzyme fragments. Two types of mtDNA occur in R. ridibunda. One shares with mtDNA of R. lessonae 25.8% of 132 fragments generated by 19 enzymes, corresponding to a nucleotide sequence divergence of 8.1%; the other has diverged from R. lessonae mtDNA by only 0.3%. This latter type is a variant R. lessonae mtDNA that has been transferred into R. ridibunda; the introgression may have occurred via the hybridogenetic hybrid lineages collectively known as Rana esculenta. Of 37 R. ridibunda from Poland, 59% had the typical R. ridibunda mtDNA; 41% had the modified R. lessonae mtDNA as did a single individual from Switzerland (introduced). A single R. ridibunda from Turkey, outside the present range of R. lessonae, had the typical R. ridibunda mtDNA phenotype. Discordancies between inheritance of mitochondrial and nuclear genomes point up the danger of relying on a single molecular feature in reconstructing phylogeny. In addition, studies of mtDNA provide otherwise inaccessible information on complex evolutionary histories of closely related species. A knowledge of these complexities is important to an understanding of phylogenetic relationships and of the genetic processes that underlie the evolution of clonal taxa. PMID:6091109

Spolsky, C; Uzzell, T

1984-09-01

407

Natural interspecies transfer of mitochondrial DNA in amphibians.  

PubMed Central

mtDNAs of two Central European water frog species, Rana ridibunda and Rana lessonae, were examined by electrophoresis of restriction enzyme fragments. Two types of mtDNA occur in R. ridibunda. One shares with mtDNA of R. lessonae 25.8% of 132 fragments generated by 19 enzymes, corresponding to a nucleotide sequence divergence of 8.1%; the other has diverged from R. lessonae mtDNA by only 0.3%. This latter type is a variant R. lessonae mtDNA that has been transferred into R. ridibunda; the introgression may have occurred via the hybridogenetic hybrid lineages collectively known as Rana esculenta. Of 37 R. ridibunda from Poland, 59% had the typical R. ridibunda mtDNA; 41% had the modified R. lessonae mtDNA as did a single individual from Switzerland (introduced). A single R. ridibunda from Turkey, outside the present range of R. lessonae, had the typical R. ridibunda mtDNA phenotype. Discordancies between inheritance of mitochondrial and nuclear genomes point up the danger of relying on a single molecular feature in reconstructing phylogeny. In addition, studies of mtDNA provide otherwise inaccessible information on complex evolutionary histories of closely related species. A knowledge of these complexities is important to an understanding of phylogenetic relationships and of the genetic processes that underlie the evolution of clonal taxa. Images

Spolsky, C; Uzzell, T

1984-01-01

408

Potential of Trap Crops for Integrated Management of the Tropical Armyworm, Spodoptera litura in Tobacco  

PubMed Central

The tropical armyworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae), is an important pest of tobacco, Nicotiana tabacum L. (Solanales: Solanaceae), in South China that is becoming increasingly resistant to pesticides. Six potential trap crops were evaluated to control S. litura on tobacco. Castor bean, Ricinus communis L. (Malpighiales: Euphorbiaceae), and taro, Colocasia esculenta (L.) Schott (Alismatales: Araceae), hosted significantly more S. litura than peanut, Arachis hypogaea L. (Fabales: Fabaceae), sweet potato, Ipomoea batata Lam. (Solanales: Convolvulaceae) or tobacoo in a greenhouse trial, and tobacco field plots with taro rows hosted significantly fewer S. litura than those with rows of other trap crops or without trap crops, provided the taro was in a fast-growing stage. When these crops were grown along with eggplant, Solanum melongena L. (Solanales: Solanaceae), and soybean, Glycines max L. (Fabales: Fabaceae), in separate plots in a randomized matrix, tobacco plots hosted more S. litura than the other crop plots early in the season, but late in the season, taro plots hosted significantly more S. litura than tobacco, soybean, sweet potato, peanut or eggplant plots. In addition, higher rates of S. litura parasitism by Microplitis prodeniae Rao and Chandry (Hymenoptera: Bracondidae) and Campoletis chlorideae Uchida (Ichnumonidae) were observed in taro plots compared to other crop plots. Although taro was an effective trap crop for managing S. litura on tobacco, it did not attract S. litura in the seedling stage, indicating that taro should either be planted 20–30 days before tobacco, or alternative control methods should be employed during the seedling stage.

Zhou, Zhongshi; Chen, Zepeng; Xu, Zaifu

2010-01-01

409

Genetic variation and variation in aggressiveness to native and exotic hosts among Brazilian populations of Ceratocystis fimbriata.  

PubMed

Ceratocystis fimbriata is a complex of many species that cause wilt and cankers on woody plants and rot of storage roots or corms of many economically important crops worldwide. In Brazil, C. fimbriata infects different cultivated crop plants that are not native to Brazil, including Gmelina arborea, Eucalyptus spp., Mangifera indica (mango), Ficus carica (fig), and Colocasia esculenta (inhame). Phylogenetic analyses and inoculation studies were performed to test the hypothesis that there are host-specialized lineages of C. fimbriata in Brazil. The internal transcribed spacer region ribosomal DNA sequences varied greatly but there was little resolution of lineages based on these sequences. A portion of the MAT1-2 mating type gene showed less variation, and this variation corresponded more closely with host of origin. However, mango isolates were found scattered throughout the tree. Inoculation experiments on the five exotic hosts showed substantial variation in aggressiveness within and among pathogen populations. Native hosts from the same families as the exotic hosts tended to be less susceptible than the cultivated hosts, but there was little correlation between aggressiveness to the cultivated and native hosts of the same family. Cultivation and vegetative propagation of exotic crops may select for strains that are particularly aggressive on those crops. PMID:21190423

Harrington, Thomas C; Thorpe, Daniel J; Alfenas, Acelino C

2011-05-01

410

Identification of Drought-Responsive Universal Stress Proteins in Viridiplantae  

PubMed Central

Genes encoding proteins that contain the universal stress protein (USP) domain are known to provide bacteria, archaea, fungi, protozoa, and plants with the ability to respond to a plethora of environmental stresses. Specifically in plants, drought tolerance is a desirable phenotype. However, limited focused and organized functional genomic datasets exist on drought-responsive plant USP genes to facilitate their characterization. The overall objective of the investigation was to identify diverse plant universal stress proteins and Expressed Sequence Tags (ESTs) responsive to water-deficit stress. We hypothesize that cross-database mining of functional annotations in protein and gene transcript bioinformatics resources would help identify candidate drought-responsive universal stress proteins and transcripts from multiple plant species. Our bioinformatics approach retrieved, mined and integrated comprehensive functional annotation data on 511 protein and 1561 ESTs sequences from 161 viridiplantae taxa. A total of 32 drought-responsive ESTs from 7 plant genera Glycine, Hordeum, Manihot, Medicago, Oryza, Pinus and Triticum were identified. Two Arabidopsis USP genes At3g62550 and At3g53990 that encode ATP-binding motif were up-regulated in a drought microarray dataset. Further, a dataset of 80 simple sequence repeats (SSRs) linked to 20 singletons and 47 transcript assembles was constructed. Integrating the datasets on SSRs and drought-responsive ESTs identified three drought-responsive ESTs from bread wheat (BE604157), soybean (BM887317) and maritime pine (BX682209). The SSR sequence types were CAG, ATA and AT respectively. The datasets from cross-database mining provide organized resources for the characterization of USP genes as useful targets for engineering plant varieties tolerant to unfavorable environmental conditions.

Isokpehi, Raphael D.; Simmons, Shaneka S.; Cohly, Hari H.P.; Ekunwe, Stephen I.N.; Begonia, Gregorio B.; Ayensu, Wellington K.

2011-01-01

411

Identification of drought-responsive universal stress proteins in viridiplantae.  

PubMed

Genes encoding proteins that contain the universal stress protein (USP) domain are known to provide bacteria, archaea, fungi, protozoa, and plants with the ability to respond to a plethora of environmental stresses. Specifically in plants, drought tolerance is a desirable phenotype. However, limited focused and organized functional genomic datasets exist on drought-responsive plant USP genes to facilitate their characterization. The overall objective of the investigation was to identify diverse plant universal stress proteins and Expressed Sequence Tags (ESTs) responsive to water-deficit stress. We hypothesize that cross-database mining of functional annotations in protein and gene transcript bioinformatics resources would help identify candidate drought-responsive universal stress proteins and transcripts from multiple plant species. Our bioinformatics approach retrieved, mined and integrated comprehensive functional annotation data on 511 protein and 1561 ESTs sequences from 161 viridiplantae taxa. A total of 32 drought-responsive ESTs from 7 plant genera Glycine, Hordeum, Manihot, Medicago, Oryza, Pinus and Triticum were identified. Two Arabidopsis USP genes At3g62550 and At3g53990 that encode ATP-binding motif were up-regulated in a drought microarray dataset. Further, a dataset of 80 simple sequence repeats (SSRs) linked to 20 singletons and 47 transcript assembles was constructed. Integrating the datasets on SSRs and drought-responsive ESTs identified three drought-responsive ESTs from bread wheat (BE604157), soybean (BM887317) and maritime pine (BX682209). The SSR sequence types were CAG, ATA and AT respectively. The datasets from cross-database mining provide organized resources for the characterization of USP genes as useful targets for engineering plant varieties tolerant to unfavorable environmental conditions. PMID:21423406

Isokpehi, Raphael D; Simmons, Shaneka S; Cohly, Hari H P; Ekunwe, Stephen I N; Begonia, Gregorio B; Ayensu, Wellington K

2011-02-07

412

Isolation of terminal cisternae of frog skeletal muscle. Calcium storage and release properties.  

PubMed

Sarcoplasmic reticulum (SR) terminal cisternae (TC) of frog (Rana esculenta) fast-twitch skeletal muscle have been purified by isopycnic sucrose density gradient centrifugation. Biochemical characteristics and Ca2+ release properties have been investigated and compared to those of the homologous fraction of rabbit skeletal muscle TC. The frog SR fraction obtained at the 38/45% sucrose interface appears to be derived from the terminal cisternae region as judged by: (a) thin section electron microscopy showing vesicles containing electron opaque material and squarelike (feet) projections at the outer surface; (b) protein composition (Ca2+-ATPase, calsequestrin, and high Mr proteins); (c) Ca2+ fluxes properties. The content of calsequestrin was higher in frog TC by 50% and the Ca2+ binding capacity (624 or 45 nmol of Ca2+/mg of TC protein, depending upon experimental conditions) was 3-4 times that of rabbit TC. Species-specific antigenic differences were found between junctional SR proteins of frog and rabbit TC. After active Ca2+ preloading in the presence of pyrophosphate (Palade, P. (1987) J. Biol. Chem. 262, 6135-6141), caffeine and doxorubicin elicited Ca2+ release from either TC fraction but with much faster rates in frog TC than in rabbit TC (14 versus 3 mumol of Ca2+/min/mg of protein). The present results provide new evidence for the existence of marked differences in Ca2+ release properties between TC of amphibian and mammalian fast-twitch muscle. Higher Ca2+ binding capacity and faster release rates in frog TC might compensate for the comparably greater diffusion distance being covered by the released Ca2+ from the Z-line to the actomyosin cross-bridges in the A-I overlap region. PMID:2968342

Volpe, P; Bravin, M; Zorzato, F; Margreth, A

1988-07-15

413

Serum IGF-1 Concentrations Change With Soy and Seaweed Supplements in Healthy Postmenopausal American Women  

PubMed Central

Insulin-like growth factor 1 (IGF-1) is an anabolic hormone important for growth and development. However, high-circulating serum concentrations in adults are associated with increased risk of postmenopausal breast cancer. Nutritional status and specific foods influence serum IGF-1 concentrations. Breast cancer incidence is typically low in Asian countries where soy is commonly consumed. Paradoxically, soy supplement trials in American women have reported significant increases in IGF-1. Seaweed also is consumed regularly in Asian countries where breast cancer risk is low. We investigated the possibility that seaweed could modify soy-associated increases in IGF-1 in American women. Thirty healthy postmenopausal women (mean age 58 yr) participated in this 14-wk double-blinded, randomized, placebo-controlled crossover clinical trial. Participants consumed 5 g/day placebo or seaweed (Alaria esculenta) in capsules for 7 wk. During the 7th wk, a high-soy protein isolate powder was added (2 mg/kg body weight aglycone equivalent isoflavones). Overnight fasting blood samples were collected after each intervention period. Soy significantly increased serum IGF-1 concentrations compared to the placebo (21.2 nmol/L for soy vs. 16.9 nmol/L for placebo; P = 0.0001). The combination of seaweed and soy significantly reduced this increase by about 40% (21.2 nmol/L for soy alone vs. 19.4 nmol/L; P = 0.01). Concurrent seaweed and soy consumption may be important in modifying the effect of soy on IGF-1 serum concentrations.

Teas, Jane; Irhimeh, Mohammad R.; Druker, Susan; Hurley, Thomas G.; Hebert, James R.; Savarese, Todd M.; Kurzer, Mindy S.

2011-01-01

414

Serum IGF-1 concentrations change with soy and seaweed supplements in healthy postmenopausal American women.  

PubMed

Insulin-like growth factor 1 (IGF-1) is an anabolic hormone important for growth and development. However, high-circulating serum concentrations in adults are associated with increased risk of postmenopausal breast cancer. Nutritional status and specific foods influence serum IGF-1 concentrations. Breast cancer incidence is typically low in Asian countries where soy is commonly consumed. Paradoxically, soy supplement trials in American women have reported significant increases in IGF-1. Seaweed also is consumed regularly in Asian countries where breast cancer risk is low. We investigated the possibility that seaweed could modify soy-associated increases in IGF-1 in American women. Thirty healthy postmenopausal women (mean age 58 yr) participated in this 14-wk double-blinded, randomized, placebo-controlled crossover clinical trial. Participants consumed 5 g/day placebo or seaweed (Alaria esculenta) in capsules for 7 wk. During the 7th wk, a high-soy protein isolate powder was added (2 mg/kg body weight aglycone equivalent isoflavones). Overnight fasting blood samples were collected after each intervention period. Soy significantly increased serum IGF-1 concentrations compared to the placebo (21.2 nmol/L for soy vs. 16.9 nmol/L for placebo; P = 0.0001). The combination of seaweed and soy significantly reduced this increase by about 40% (21.2 nmol/L for soy alone vs. 19.4 nmol/L; P = 0.01). Concurrent seaweed and soy consumption may be important in modifying the effect of soy on IGF-1 serum concentrations. PMID:21711174

Teas, Jane; Irhimeh, Mohammad R; Druker, Susan; Hurley, Thomas G; Hébert, James R; Savarese, Todd M; Kurzer, Mindy S

2011-06-28

415

A promoter derived from taro bacilliform badnavirus drives strong expression in transgenic banana and tobacco plants.  

PubMed

Taro bacilliform virus (TaBV) is a pararetrovirus of the genus Badnavirus which infects the monocotyledonous plant, taro ( Colocasia esculenta). A region of the TaBV genome spanning nucleotides 6,281 to 12 (T1200), including the 3' end of open reading frame 3 (ORF 3) and the intergenic region to the end of the tRNA(met)-binding site, was tested for promoter activity along with four different 5' deletion fragments (T600, T500, T250 and T100). In transient assays, only the T1200, T600, T500 fragments were shown to have promoter activity in taro leaf, banana suspension cells and tobacco callus. When these three promoters were evaluated in stably transformed, in vitro-grown transgenic banana and tobacco plants, all were found to drive near-constitutive expression of either the green fluorescent protein or beta-glucuronidase (GUS) reporter gene in the stem (or pseudostem), leaves and roots, with strongest expression observed in the vascular tissue. In transgenic banana leaves, the T600 promoter directed four-fold greater GUS activity than that of the T1200, T500 and the maize polyubiquitin-1 promoters. In transgenic tobacco leaves, the levels of GUS expression directed by the three promoters was between four- and ten-fold lower than that of the double Cauliflower mosaic virus 35S promoter. These results indicate that the TaBV-derived promoters may be useful for the high-level constitutive expression of transgenes in either monocotyledonous or dicotyledonous species. PMID:12910370

Yang, I C; Iommarini, J P; Becker, D K; Hafner, G J; Dale, J L; Harding, R M

2003-05-15

416

Actinokineospora bangkokensis sp. nov., isolated from rhizospheric soil.  

PubMed

A novel actinomycete, strain 44EHW(T), was isolated from rhizospheric soil under an Elephant ear plant (Colocasia esculenta) in Bangkok, Thailand. Strain 44EHW(T) produced long branching hyphae and abundant aerial mycelia with chains of rod-shaped spores. Whole-cell hydrolysates contained galactose, glucose, arabinose, ribose, mannose and rhamnose as diagnostic sugars. meso-Diaminopimelic acid was the diamino acid and glycine, alanine and glutamic acid were present in the cell-wall peptidoglycan with the acyl type of the peptidoglycan being acetyl. Phospholipids consisted of phosphatidylethanolamine, phosphatidylethanolamine with hydroxy fatty acids and diphosphatidylglycerol, as well as other unknown phospholipids; however, no mycolic acids were detected. The predominant menaquinone observed was MK-9(H4) and major fatty acids were iso-C16 : 0 and 2-OH iso-C16 : 0. The G+C content of genomic DNA was 74 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that this isolate was most similar to Actinokineospora enzanensis NBRC 16517(T). However, DNA-DNA hybridization revealed a low relatedness between this isolate and A. enzanensis NBRC 16517(T), indicating that this isolate represented a novel species in the genus Actinokineospora. On the basis of 16S rRNA gene sequence analysis, phenotypic characteristics and DNA-DNA hybridization data, we propose that strain 44EHW(T) represents a novel species in the genus Actinokineospora, Actinokineospora bangkokensis. The type strain is 44EHW(T) ( = BCC 53155(T) = NBRC 108932(T)). PMID:23291892

Intra, Bungonsiri; Matsumoto, Atsuko; Inahashi, Yuki; Omura, Satoshi; Takahashi, Yoko; Panbangred, Watanalai

2013-01-04

417

Modulation of calcium current gating in frog skeletal muscle by conditioning depolarization.  

PubMed Central

1. Ca2+ inward currents were measured by voltage clamping cut skeletal muscle fibres of the frog (Rana esculenta) in a double-Vaseline-gap system. 2. In order to study the basis of the previously described fast gating mode induced in the Ca2+ inward current by a conditioning depolarization we quantitatively analysed the response to differing features of the conditioning prepulse. 3. The faster activation seen during the second of two depolarizations was confined to the component of the inward current which could be blocked by 5 to 10 microM nifedipine. 4. By applying depolarizing conditioning pulses of gradually increasing length the time course of the transition to the fast gating mode could be determined. 5. Both the transition to the fast gating mode (point 4) caused by a depolarization and the slow inward current activated during the same depolarization showed similar voltage-dependent kinetics. 6. The kinetic change of the test current appeared to be equal when the same fractional activation was achieved at the end of the conditioning pulse independent of its duration or amplitude. 7. Flash photolysis of nifedipine in the interval between conditioning and test pulse showed that the predepolarization causes a rate-enhancing effect even though the slow channels were blocked by nifedipine during the conditioning pulse. 8. We conclude that the transition of the calcium channel from its slow to its fast gating mode is determined by the slow voltage-dependent reaction which limits the rate of channel opening under control conditions. This reaction is apparently not prevented by the binding of nifedipine and the block of current flow through the channel.

Feldmeyer, D; Melzer, W; Pohl, B; Zollner, P

1992-01-01

418

Inhibition of proliferation by agricultural plant extracts in seven human adult T-cell leukaemia (ATL)-related cell lines.  

PubMed

Adult T-cell leukaemia (ATL) is caused by human T-cell leukaemia virus type I (HTLV-I) infection and is resistant to conventional chemotherapy. We evaluated the inhibitory effects of agricultural plants on the proliferation of seven ATL-related human leukaemia cells, using three ATL cell lines (ED, Su9T01 and S1T), two human T-cell lines transformed by HTLV-I infection (HUT-102 and MT-2) and two HTLV-I-negative human T-cell acute lymphoblastic leukaemia cell lines (Jurkat and MOLT-4). A total of 52 samples of 80% ethanol extracts obtained from 30 types of agricultural plants were examined. On the basis of IC(50) values, we selected samples with greater activity than genistein, which was used as a positive control. The highest inhibitory effect was observed with extracts from leaves of Vaccinium virgatum Aiton (blueberry) on four cell lines (ED, Su9T01, HUT-102 and Jurkat); seeds of Momordica charantia L. (bitter gourd) exhibited the second highest activity. The bitter gourd seeds suppressed the proliferation of three cell lines (Su9T01, HUT-102 and Jurkat). The extracts from edible parts of Ipomea batatas LAM. (sweet potato), edible parts of Colocasia esculenta (L.) Schott (taro), skin of taro and seeds of Prunus mume Sieb. et Zucc. (mume) showed markedly greater inhibitory effects on Su9T01 than genistein. These findings suggest that ATL-preventative bioactive compounds may exist in these agricultural plants, which are considered to be functional foods. PMID:21293936

Kai, Hisahiro; Akamatsu, Ena; Torii, Eri; Kodama, Hiroko; Yukizaki, Chizuko; Sakakibara, Yoichi; Suiko, Masahito; Morishita, Kazuhiro; Kataoka, Hiroaki; Matsuno, Koji

2011-02-04

419

Ranavirus phylogeny and differentiation based on major capsid protein, DNA polymerase and neurofilament triplet H1-like protein genes.  

PubMed

In this study, we developed new methods for differentiation of ranaviruses based on polymerase chain reaction and restriction enzyme analysis of DNA polymerase and neurofilament triplet H1-like (NF-H1) protein gene. Using these methods, we were able to differentiate the 6 known ranaviruses--Bohle iridovirus (BIV), European catfish virus (ECV), epizootic haematopoietic necrosis virus (EHNV), European sheatfish virus (ESV), frog virus 3 (FV3) and Singapore grouper iridovirus (SGIV)--with 3 less characterised virus isolates: short-finned eel ranavirus (SERV), Rana esculenta virus Italy 282/I02 (REV 282/I02) and pike-perch iridovirus (PPIV). Doctor fish virus (DFV) and guppy virus 6 (GV6) were distinguished as a group from the other viruses. In addition, all 11 isolates were analysed and compared based on nucleotide sequences from 3 different genomic regions: major capsid protein (MCP), DNA polymerase and NF-H1. The partial DNA polymerase gene was sequenced from all analysed viruses. The complete sequence of the MCP and a fragment of the NF-H1 gene were obtained from BIV, ECV, EHNV, ESV, FV3, PPIV, REV 282/I02 and SERV. With the exception of GV6, DFV and SGIV, the sequence analyses showed only a few variations within the analysed viruses. The sequence data suggest that PPIV, REV 282/I02 and SERV are new members of the genus Ranavirus. The methods developed in this study provide tools to differentiate between closely related ranaviruses of different host and geographical origin. PMID:19694168

Holopainen, R; Ohlemeyer, S; Schütze, H; Bergmann, S M; Tapiovaara, H

2009-06-10

420

Susceptibility of the European common frog Rana temporaria to a panel of ranavirus isolates from fish and amphibian hosts.  

PubMed

Ranaviruses are an emerging group of viruses and have been implicated in an increase of epidemics in susceptible species. They have a wide host range, infecting fish, amphibians and reptiles, with some isolates able to infect multiple species from different animal classes. Whilst some information exists on the pathogenicity of ranaviruses to novel hosts, there is none on the pathogenicity of fish ranaviruses to amphibians; this information is needed to develop measures to prevent the further spread of ranaviral disease in the aquatic environment. We undertook bath infection trials to assess the susceptibility of the European common frog Rana temporaria to 9 ranavirus isolates comprising doctor fish virus (DFV), European sheatfish virus (ESV), epizootic haematopoietic necrosis virus (EHNV), guppy virus 6 (GV6), pike-perch iridovirus (PPIV) and short-finned eel ranavirus (SERV) from fish hosts, and Bohle iridovirus (BIV), frog virus 3 (FV3) and Rana esculenta virus 282/I02 (REV) from amphibians. Animals were challenged as tadpoles at 15 and 20°C and as recent metamorphs at room temperature (20 ± 1°C) to investigate the effect of temperature and amphibian developmental stage on virus pathogenicity. Tadpoles were susceptible to FV3, PPIV and REV, but refractory to the other ranaviruses. Post-metamorphs were susceptible to FV3 and REV but refractory to BIV (the other ranaviruses were not tested). Significant mortality occurred in post-metamorphs and in tadpoles challenged at 20°C but was low in tadpoles challenged at 15°C. This study presents the first evidence of mortality in an amphibian species after challenge with ranavirus originally isolated from fish. PMID:23574703

Bayley, Amanda E; Hill, Barry J; Feist, Stephen W

2013-04-11

421

Conduction velocities in amphibian skeletal muscle fibres exposed to hyperosmotic extracellular solutions  

PubMed Central

Early quantitative analyses of conduction velocities in unmyelinated nerve studied in a constantly iso-osmotic volume conductor were extended to an analysis of the effects of varying extracellular osmolarities on conduction velocities of surface membrane action potentials in Rana esculenta skeletal muscle fibres. Previous papers had reported that skeletal muscle fibres exposed to a wide range of extracellular sucrose concentrations resemble perfect osmometers with increased extracellular osmolarity proportionally decreasing fibre volume and therefore diminishing fibre radius, a. However, classical electrolyte theory (Robinson and Stokes 1959, Electrolyte solutions 2nd edn. Butterworth & Co. pp 41–42) would then predict that the consequent increases in intracellular ionic strength would correspondingly decrease sarcoplasmic resistivity, Ri. An extension of the original cable analysis then demonstrated that the latter would precisely offset its expected effect of alterations in a on the fibre axial resistance, ri, and leave action potential conduction velocity constant. In contrast, other reports (Hodgkin and Nakajima J Physiol 221:105–120, 1972) had suggested that Riincreased with extracellular osmolarity, owing to alterations in cytosolic viscosity. This led to a prediction of a decreased conduction velocity. These opposing hypotheses were then tested in muscle fibres subject to just-suprathreshold stimulation at a Vaseline seal at one end and measuring action potentials and their first order derivatives, dV/dt, using 5–20 M?, 3 M KCl glass microelectrodes at defined distances away from the stimulus sites. Exposures to hyperosmotic, sucrose-containing, Ringer solutions then reversibly reduced both conduction velocity and maximum values of dV/dt. This was compatible with an increase in Ri in the event that conduction depended upon a discharge of membrane capacitance by propagating local circuit currents through initially passive electrical elements. Conduction velocity then showed graded decreases with increasing extracellular osmolarity from 250–750 mOsm. Action potential waveforms through these osmolarity changes remained similar, including both early surface and the late after-depolarisation events reflecting transverse tubular activation. Quantitative comparisons of reduced-? 2 values derived from a comparison of these results and the differing predictions from the two hypotheses strongly favoured the hypothesis in which Riincreased rather than decreased with hyperosmolarity. Electronic supplementary material The online version of this article (doi:10.1007/s10974-007-9115-8) contains supplementary material, which is available to authorized users.

Chen, Zhongbo; Hothi, Sandeep S.; Xu, Wei

2007-01-01

422

Exposure to ultraviolet radiation delays photosynthetic recovery in Arctic kelp zoospores.  

PubMed

Seasonal reproduction in some Arctic Laminariales coincides with increased UV-B radiation due to stratospheric ozone depletion and relatively high water temperatures during polar spring. To find out the capacity to cope with different spectral irradiance, the kinetics of photosynthetic recovery was investigated in zoospores of four Arctic species of the order Laminariales, the kelps Saccorhiza dermatodea, Alaria esculenta, Laminaria digitata, and Laminaria saccharina. The physiology of light harvesting, changes in photosynthetic efficiency and kinetics of photosynthetic recovery were measured by in vivo fluorescence changes of Photosystem II (PSII). Saturation irradiance of freshly released spores showed minimal I ( k ) values (photon fluence rate where initial slope intersects horizontal asymptote of the curve) values ranging from 13 to 18 micromol photons m(-2) s(-1) among species collected at different depths, confirming that spores are low-light adapted. Exposure to different radiation spectra consisting of photosynthetically active radiation (PAR; 400-700 nm), PAR+UV-A radiation (UV-A; 320-400 nm), and PAR+ UV-A+UV-B radiation (UV-B; 280-320 nm) showed that the cumulative effects of increasing PAR fluence and the additional effect of UV-A and UV-B radiations on photoinhibition of photosynthesis are species specific. After long exposures, Laminaria saccharina was more sensitive to the different light treatments than the other three species investigated. Kinetics of recovery in zoospores showed a fast phase in S. dermatodea, which indicates a reduction of the photoprotective process while a slow phase in L. saccharina indicates recovery from severe photodamage. This first attempt to study photoinhibition and kinetics of recovery in zoospores showed that zoospores are the stage in the life history of seaweeds most susceptible to light stress and that ultraviolet radiation (UVR) effectively delays photosynthetic recovery. The viability of spores is important on the recruitment of the gametophytic and sporophytic life stages. The impact of UVR on the zoospores is related to the vertical depth distribution of the large sporophytes in the field. PMID:16758269

Roleda, Michael Y; Hanelt, Dieter; Wiencke, Christian

2006-06-07

423

Cell proliferation and death in the brain of active and hibernating frogs  

PubMed Central

‘Binomial’ cell proliferation and cell death have been studied in only a few non-mammalian vertebrates, such as fish. We thought it of interest to map cell proliferation/apoptosis in the brain of the frog (Rana esculenta L.) as this animal species undergoes, during the annual cycle, physiological events that could be associated with central nervous system damage. Therefore, we compared the active period and the deep underground hibernation of the frog. Using western blot analysis for proliferating cell nuclear antigen (PCNA), we revealed a positive 36 kDa band in all samples and found higher optical density values in the hibernating frogs than in active frogs. In both active and hibernating frogs, we found regional differences in PCNA-immunoreactive cells and terminal transferase dUTP nick-end labelling apoptotic cells in the ventricular zones and parenchyma areas of the main encephalon subdivisions. During the active period of the frogs, the highest concentration of PCNA-immunoreactive cells was found in the ventricle dorsal zone of the cerebral hemispheres but only some of the cells were apoptotic. By contrast, the tectal and cerebellar ventricular zones had a small or medium amount of PCNA-immunoreactive cells, respectively, and a higher number of apoptotic cells. During hibernation, an increased PCNA-immunoreactive cell number was observed in both the brain ventricles and parenchyma compared with active frogs. This increase was primarily evident in the lateral ventricles, a region known to be a proliferation ‘hot spot’. Although differences existed among the brain areas, a general increase of apoptotic cell death was found in hibernating frogs, with the highest number of apoptotic cells being detected in the parenchyma of the cerebral hemispheres and optic tectum. In particular, the increased number of apoptotic cells in the hibernating frogs compared with active frogs in the parenchyma of these brain areas occurred when cell proliferation was higher in the corresponding ventricular zones. We suggest that the high number of dying cells found in the parenchymal regions of hibernating frogs might provide the stimulus for the ventricular zones to proliferate. Hibernating frogs could utilize an increased cell proliferation in the brain areas as a neuroprotective strategy to face cell death and the onset of neurological damages. Therefore, the hibernator promises to be a valuable model for studying the mechanisms naturally carried out by the central nervous system in order to adapt itself or survive adverse conditions.

Cerri, Silvia; Bottiroli, Giovanni; Bottone, Maria Grazia; Barni, Sergio; Bernocchi, Graziella

2009-01-01

424

Measurement of the conductance of the sodium channel from current fluctuations at the node of Ranvier.  

PubMed Central

Single myelinated nerve fibres of Rana esculenta were investigated under voltage clamp conditions at 13 degrees C. Fluctuations of steady-state membrane current were measured during the last 152 msec of 190-225 msec pulses depolarizing the membrane by 8-48 mV. Noise power spectral densities were calculated in the frequency range of 6-6-6757 Hz. 2. External application of 150 nM tetrodotoxin (TTX) and/or 10 mM tetraethylammonium (TEA) ion reduced the current fluctuations. The difference of current noise spectra measured in the presence and absence of TTX (TEA) was not changed by the presence of TEA (TTX) during both measurements, and was taken as the spectrum of the Na (K) current fluctuations. 3. Residual current noise during application of both TTX and TEA was, except for some excess noise at the low and high frequency ends of the spectrum, similar to the noise measured from a passive nerve model and could be understood in terms of Nyquist noise of the known resistances and the amplifier noise. 4. Na current fluctuation spectra were interpreted as the sum N/f+SNa(f) where SNa(F) represents the spectrum expected for a set of equal, independent Na channels with only two conductance states (open or closed) which follow Hodgkin-Huxley kinetics. With values of hinfinity, tauh and minfinity measured from macroscopic Na currents, the measured spectra were fitted well by optimizing N, SNa(0) and taum. Values of taum obtained by this method were in fair agreement with values found from macroscopic currents. 5. The 1/f component of Na current noise was roughly proportional to the square of the steady-state Na current, I2. The mean value of N/I2 was (1-1 +/- 0-3) X 10(-4). 6. The current carried by a single Na channel was calculated from fitted spectra and steady-state Na currents measured simultaneously with the current fluctuations. The single channel conductance gamma normalized to zero absolute membrane potential was calculated. The average gamma from twelve measurements at depolarizations of 8-40 mV was 7-9 +/- 0-9 pS (S.E. of mean). The apparent value of gamma was smallest with small depolarizations. Variations of the assumed kinetic properties of the model did not drastically affect the single channel conductance. 7. External application of 0-1 mM-Ni ion lengthened taum in the macroscopic currents and in the fluctuation spectra and enhanced both the steady-state Na current and the current fluctuations. In Ni-treated nodes gamma was smaller than in normal nodes.

Conti, F; Hille, B; Neumcke, B; Nonner, W; Stampfli, R

1976-01-01

425

Natural pesticides and bioactive components in foods.  

PubMed

In this review, some common food plants and their toxic or otherwise bioactive components and mycotoxin contaminants have been considered. Crucifers contain naturally occurring components that are goitrogenic, resulting from the combined action of allyl isothiocyanate, goitrin, and thiocyanate. Although crucifers may provide some protection from cancer when taken prior to a carcinogen, when taken after a carcinogen they act as promoters of carcinogenesis. The acid-condensed mixture of indole-3-carbinol (a component of crucifers) binds to the TCDD receptor and causes responses similar to those of TCDD. Herbs contain many biologically active components, with more than 20% of the commercially prepared human drugs coming from these plants. Onion and garlic juices can help to prevent the rise of serum cholesterol. Most herbs used in treatments may have many natural constituents that act oppositely from their intended use. Some herbs like Bishop's week seed contain carcinogens, and many contain pyrrolizidine alkaloids that can cause cirrhosis of the liver. The general phytoalexin response in plants (including potatoes, tomatoes, peppers, eggplant, celery, and sweet potatoes) induced by external stimuli can increase the concentrations of toxic chemical constituents in those plants. In potatoes, two major indigenous compounds are alpha-solanine and alpha-chaconine, which are human plasma cholinesterase inhibitors and teratogens in animals. Because of its toxicity, the potato variety Lenape was withdrawn from the market. Celery, parsley, and parsnips contain the linear furanocoumarin phytoalexins psoralen, bergapten, and xanthotoxin that can cause photosensitization and also are photomutagenic and photocarcinogenic. Celery field workers and handlers continually have photosensitization problems as a result of these indigenous celery furanocoumarins. A new celery cultivar (a result of plant breeding to produce a more pest-resistant variety) was responsible for significant incidences of phytophotodermatitis of grocery employees. Since there is no regulatory agency or body designated to oversee potential toxicological issues associated with naturally occurring toxicants, photodermatitis continues to occur from celery exposure. Sweet potatoes contain phytoalexins that can cause lung edema and are hepatotoxic to mice. At least one of these, 4-ipomeanol, can cause extensive lung clara cell necrosis and can increase the severity of pneumonia in mice. Some phytoalexins in sweet potatoes are hepatotoxic and nephrotoxic to mice. The common mushroom Agaricus bisporus contains benzyl alcohol as its most abundant volatile, and A. bisporus and Gyromitra esculenta both contain hydrazine analogues. Mycotoxins are found in corn, cottonseed, fruits, grains, grain sorghums, and nuts (especially peanuts); therefore, they also occur in apple juice, bread, peanut butter, and other products made from contaminated starting materials.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2404325

Beier, R C

1990-01-01

426

Use of Novel Whole Core Incubations to Measure the Fate of Fertilizer N in a Flooded Agricultural System  

NASA Astrophysics Data System (ADS)

We developed a new whole-core perfusion technique for tracking the fate of 15NH4+ added to intact vegetated cores. Taro plants (Colocasia esculenta) were field-grown in (20 cm diameter) cores for three months, which allowed exchange with natural porewater, then harvested. Following core extraction, surface and porewater were removed and 15NH4+ labeled porewater was slowly re-introduced to the core through a perfusion cap in the laboratory. Mini porewater equilibrators were placed in 1 cm increments through the sediment profile for porewater extraction during incubation. We also independently tested the ability of taro roots to oxygenate the subsurface by growing plants in nutrient agar and measuring O2 flux with a microelectrode. In the agar experiment, diurnal O2 transport was monitored and the application of wind across the taro leaves was found necessary to develop an oxygenated zone at the root tips. Using this information, the harvested taro were incubated in growth chambers after perfusion using three treatments: Vegetated without wind, vegetated with wind, and a non-vegetated control. Porewater was analyzed for 29+30N2, 15NH4+, 15NO3-, and unlabeled nitrate and ammonium species. Plant uptake of 15NH4+ was also determined. Quantitative PCR was performed on the sediment profiles of functional genes involved in nitrogen cycling for correlation to N transformations. The major pathway of N loss was root-mediated nitrification/denitrification followed by a flow of 29+30N2 through the aerenchyma. The vegetated wind treatment exhibited the highest concentrations of labeled N2 in the subsurface during all time periods. In contrast, the vegetated no wind treatment had much higher aerenchyma 29+30N2 concentration, accounting for ~100% of the subsurface N2 accumulation by day three of the incubation. Surface water N2 concentrations were also highest in the no wind treatment. After nine days the 29+30N2 concentrations dropped by ~70%, with little difference remaining among the treatments, indicating limitation by 15NH4+ diffusion. These results indicate that N2 is preferentially transported through the aerenchyma in taro and probably other plants grown in flooded agricultural fields. However, increased wind stress reduced transport through the aerenchyma and resulted in greater N2 accumulation in the subsurface, which indicates the importance of mass flow transport of air and its effect on oxygenation at the root tips. The results indicate that the complexity of N cycling in flooded agricultural systems may confound attempts to estimate in-situ N losses through porewater modeling, ‘classic’ isotope pairing techniques, or N flux chambers. The whole-core technique presented here allows for the measurement of multiple N pools and fates while minimizing system disturbance and more accurately representing field conditions.

Penton, C. R.; Bruland, G. L.; Popp, B. N.; Engstrom, P.; Tiedje, J.; Brown, G. A.; Deenik, J. L.

2010-12-01

427

Deleterious alleles and differential viability in progeny of natural hemiclonal frogs.  

PubMed

Abstract.-Spontaneous deleterious mutations are expected to accumulate through Muller's ratchet in clonally reproducing organisms and may lead to their extinction. We study deleterious mutations and their effects in a system of European frogs. Rana esculenta (RL), natural hybrids R. ridibunda (RR) X R. lessonae (LL), reproduce hemiclonally; both sexes exclude the L genome in the germ line and produce unrecombined R gametes; hybridity is restored each generation by matings of RL with coexisting LL. Different allozyme-defined hybrid hemiclones (R genome haplotypes) are thought to have originated independently from primary hybridizations RR x LL. Natural matings between two hybrids usually lead to inviable RR tadpoles. This inviability is thought to result from unmasked deleterious alleles on the clonally transmitted R genomes. Most simply it reflects homozygosity for recessive deleterious alleles at particular loci; alternatively (consistent with absence of RR adults in multiclonal populations) it may reflect hemiclone-specific sets of incompletely recessive deleterious mutations that cumulatively cause inviability when two such genomes are combined. If inviability results from the former, progeny of two hybrids of different hemiclones, whether allopatric or coexisting, should be viable, because it is improbable that their R genomes share recessive deleterious alleles at the same set of loci; if inviability results from the latter, progeny of hybrids of different hemiclones should be inviable, especially when hybrid lineages are old. We tested these hypotheses in artificial crosses, using frogs from three regions: hemiclonal hybrids outside R. ridibunda's range from northern Switzerland (two abundant coexisting allozyme-defined hemiclones; estimated lineage age < or = 5,000 generations) and from Sicily, Italy (one hemiclone; estimated age > or = 25,000 generations) and R. ridibunda from Poland. We generated RR progeny, which we reared under benign conditions in the laboratory, by crossing (1) two hybrids from the same region (H x H local); (2) two hybrids from different regions (H X H foreign); (3) hybrids and R. ridibunda (H X R); and (4) two R. ridibunda (R X R). Survival to metamorphosis was similar and high for R x R, H X H foreign, and H X R, whereas all tadpoles of H X H local died before metamorphosis. This supports the hypothesis that homozygosity for recessive deleterious mutations at particular loci causes inviability. Crosses within and between the two coexisting hemiclones from Switzerland were, however, equally inviable. This result may reflect episodic sexual recombination in RR progeny from exceptional successful interclonal hybrid X hybrid matings, followed by matings of such RR with LL. This process would both slow down or halt Muller's ratchet and disrupt genetic independence of coexisting hemiclones, so that the same remaining deleterious R alleles could exist in different allozyme-defined hemiclones. Whereas all data are consistent with the prediction of Muller's ratchet operating on clonally transmitted R genomes of natural hybrid lineages, they are insufficient to demonstrate such operation, because deleterious recessives that mutated after clone formation and those that preexisted in the R. ridibunda source populations that formed the hemiclonal lineages are not distinguished. The possibility of episodic sexual recombination must be carefully taken into account when studying Muller's ratchet in natural populations of this Rana system. PMID:12093017

Guex, Gaston-Denis; Hotz, Hansjurg; Semlitsch, Raymond D

2002-05-01