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Sample records for yuca manihot esculenta

  1. Cassava (Manihot esculenta Crantz).

    PubMed

    Bull, Simon E

    2015-01-01

    Genetic transformation of plants is an indispensable technique used for fundamental research and crop improvement. Recent advances in cassava (Manihot esculenta Crantz) transformation have facilitated the effective generation of stably transformed cassava plants with favorable traits. Agrobacterium-mediated transformation of friable, embryogenic callus has evolved to become the most widely used approach and has been adopted by research laboratories in Africa. This procedure utilizes axillary meristem tissue (buds) to produce primary and secondary somatic embryos and subsequently friable, embryogenic callus. Agrobacterium harboring a binary expression cassette is used to transform this tissue, which is regenerated via cotyledons and shoot organogenesis to produce rooted in vitro plantlets. This chapter details each step of the procedure using the model cultivar 60444 and provides supplementary notes to successfully produce transgenic cassava. PMID:25416250

  2. Two new terpenoids from the stems of Manihot esculenta.

    PubMed

    Zeng, Yan-Bo; Li, Shan-Shan; Mei, Wen-Li; Dong, Wen-Hua; Li, Kai-Mian; Dai, Hao-Fu

    2015-01-01

    A new eremophilane sesquiterpene, sporogen AO-2 (1), and a new beyerane diterpene, thecacorin C (2), together with two known compounds, longifoamide-B (3) and methylcholestane-3β,5α,6β-triol (4), were isolated from the stems of Manihot esculenta. The structures of the two new compounds were determined by spectroscopic techniques (UV, IR, MS, 1D, and 2D NMR). Antimicrobial assay showed that compound 3 possessed modest inhibitory effects on Saphylococcus aureus and methicillin-resistant S.aureus, diameters of inhibition zones of which were 7.5 and 8.0 mm, respectively. Compound 4 possessed modest inhibitory effect on S. aureus, the diameter of inhibition zone of which was 6.8 mm. PMID:25492303

  3. Household utilization of Manioc (Manihot esculenta Crantz) in Northern Mozambique.

    PubMed

    Muoki, Penina N; Maziya-Dixon, Bussie

    2010-01-01

    Mozambique is ranked ninth of top manioc (Manihot esculenta Crantz) producing countries in the world. Manioc roots are a staple to people living in the northern part of the country. Despite this, information on production, utilization, postharvest handling, and marketing is scarce. The purpose of this baseline study was to document selected information on manioc, from the production to marketing stage. To gather this information, 70 focus groups consisting of 1,724 participants purposely sampled from 10 districts were engaged in discussions using a questionnaire. The results show that manioc is the most important crop in terms of contribution to household food security and income in the region. Both men and women participate in the delivery of manioc production chain. Typically, 5 to 15 varieties identified by local language can be found on most farms in the study area. Manioc leaves and roots are the parts of the plant used as human food. Sun dried manioc roots are principally marketed within the locality of production by individual farmers. This baseline study suggests the need for location-targeted interventions as the farmers reported varied challenges along the manioc production chain. PMID:21888575

  4. Gene-based Microsatellites for Cassava (Manihot esculenta Crantz): Prevalence, Polymorphisms, and Cross-taxa Utility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 large...

  5. Unveiling the Micronome of Cassava (Manihot esculenta Crantz)

    PubMed Central

    2016-01-01

    MicroRNAs (miRNAs) are an important class of endogenous non-coding single-stranded small RNAs (21–24 nt in length), which serve as post-transcriptional negative regulators of gene expression in plants. Despite the economic importance of Manihot esculenta Crantz (cassava) only 153 putative cassava miRNAs (from multiple germplasm) are available to date in miRBase (Version 21), and identification of a number of miRNAs from the cassava EST database have been limited to comparisons with Arabidopsis. In this study, mature sequences of all known plant miRNAs were used as a query for homologous searches against cassava EST and GSS databases, and additional identification of novel and conserved miRNAs were gleaned from next generation sequencing (NGS) of two cassava landraces (T200 from southern Africa and TME3 from West Africa) at three different stages post explant transplantation and acclimatization. EST and GSS derived data revealed 259 and 32 miRNAs in cassava, and one of the miRNA families (miR2118) from previous studies has not been reported in cassava. NGS data collectively displayed expression of 289 conserved miRNAs in leaf tissue, of which 230 had not been reported previously. Of the 289 conserved miRNAs identified in T200 and TME3, 208 were isomiRs. Thirty-nine novel cassava-specific miRNAs of low abundance, belonging to 29 families, were identified. Thirty-eight (98.6%) of the putative new miRNAs identified by NGS have not been previously reported in cassava. Several miRNA targets were identified in T200 and TME3, highlighting differential temporal miRNA expression between the two cassava landraces. This study contributes to the expanding knowledge base of the micronome of this important crop. PMID:26799216

  6. Unveiling the Micronome of Cassava (Manihot esculenta Crantz).

    PubMed

    Rogans, Sarah Jane; Rey, Chrissie

    2016-01-01

    MicroRNAs (miRNAs) are an important class of endogenous non-coding single-stranded small RNAs (21-24 nt in length), which serve as post-transcriptional negative regulators of gene expression in plants. Despite the economic importance of Manihot esculenta Crantz (cassava) only 153 putative cassava miRNAs (from multiple germplasm) are available to date in miRBase (Version 21), and identification of a number of miRNAs from the cassava EST database have been limited to comparisons with Arabidopsis. In this study, mature sequences of all known plant miRNAs were used as a query for homologous searches against cassava EST and GSS databases, and additional identification of novel and conserved miRNAs were gleaned from next generation sequencing (NGS) of two cassava landraces (T200 from southern Africa and TME3 from West Africa) at three different stages post explant transplantation and acclimatization. EST and GSS derived data revealed 259 and 32 miRNAs in cassava, and one of the miRNA families (miR2118) from previous studies has not been reported in cassava. NGS data collectively displayed expression of 289 conserved miRNAs in leaf tissue, of which 230 had not been reported previously. Of the 289 conserved miRNAs identified in T200 and TME3, 208 were isomiRs. Thirty-nine novel cassava-specific miRNAs of low abundance, belonging to 29 families, were identified. Thirty-eight (98.6%) of the putative new miRNAs identified by NGS have not been previously reported in cassava. Several miRNA targets were identified in T200 and TME3, highlighting differential temporal miRNA expression between the two cassava landraces. This study contributes to the expanding knowledge base of the micronome of this important crop. PMID:26799216

  7. Nutritional composition of "gari" analog produced from cassava (Manihot esculenta) and cocoyam (Colocasia esculenta) tuber.

    PubMed

    Bamidele, Oluwaseun P; Ogundele, Femi G; Ojubanire, Basirat A; Fasogbon, Mofoluwaso B; Bello, Olayide W

    2014-11-01

    Physicochemical properties ofgari analog produced from coprocessing of Cassava (Manihot esculenta Crantz) and Cocoyam (Colocasia esculenta) were investigated. Cassava tuber and cocoyam were coprocessed at different percentages before frying separately. Proximate composition, mineral content, antinutritional factors, and sensory evaluation of various samples were determined. The results showed that the moisture content of all the samples was in the same range (7.28 ± 0.30 to 7.78 ± 0.14%). The protein content (1.57 ± 0.14 to 4.43 ± 0.16), ash (1.89 ± 0.10 to 2.15 ± 0.30), and crude fiber (1.53 ± 0.50 to 2.19 ± 0.10%) showed a significant increase with increase in the level of cocoyam substitution. The fat and carbohydrate content decreased with an increase in cocoyam level. The mineral contents of the samples increased with an increase in cocoyam content with sample F having the highest value of potassium, followed by samples E and D (68 mg/100 g, 35 mg/100 g, and 24 mg/100 g). The antinutritional factors of all the samples were at very low concentration while samples B, C, and D competed favorably with sample A (control) in sensory evaluation. In conclusion, coprocessing of cassava and cocoyam improved the nutritional quality of thegari produced with high level of acceptance from the taste panelist. PMID:25493189

  8. Reprogramming of cassava (Manihot esculenta) microspores towards sporophytic development

    PubMed Central

    Perera, P. I. P.; Ordoñez, C. A.; Dedicova, B.; Ortega, P. E. M.

    2014-01-01

    Gametes have the unique potential to enter the sporophytic pathway, called androgenesis. The plants produced are usually haploid and recombinant due to the preceding meiosis and they can double their chromosome number to form doubled haploids, which are completely homozygous. Availability of the doubled haploids facilitates mapping the genes of agronomically important traits, shortening the time of the breeding process required to produce new hybrids and homozygous varieties, and saving the time and cost for inbreeding. This study aimed to test the feasibility of using isolated and in vitro cultured immature cassava (Manihot esculenta) microspores to reprogramme and initiate sporophytic development. Different culture media and different concentrations of two ion components (Cu2+ and Fe2+) were tested in two genotypes of cassava. External structural changes, nuclear divisions and cellular changes during reprogramming were analysed by scanning electron microscopy, by staining with 4′,6-diamidino-2-phenylindole, and through classical histology and transmission electron microscopy. In two cassava genotypes, different developmental stages of microspores were found to initiate sporophytic cell divisions, that is, with tetrads of TMS 60444 and with mid or late uni-nucleate microspores of SM 1219-9. In the modified NLN medium (NLNS), microspore enlargements were observed. The medium supplemented with either sodium ferrous ethylene-diamine-tetraacetic acid (NaFeEDTA) or CuSO4·5H2O induced sporophytic cell division in both genotypes. A low frequency of the reprogramming and the presence of non-responsive microspores among the responsive ones in tetrads were found to be related to the viability and exine formation of the microspores. The present study clearly demonstrated that reprogramming occurs much faster in isolated microspore culture than in anther culture. This paves the way for the development of an efficient technique for the production of homozygous lines in cassava. This is the first ever detailed report of microspore reprogramming at the tetrad stage and the first report of microspore embryogenesis induction in cassava with detailed evidence. PMID:24887001

  9. Reprogramming of cassava (Manihot esculenta) microspores towards sporophytic development.

    PubMed

    Perera, P I P; Ordoñez, C A; Dedicova, B; Ortega, P E M

    2014-01-01

    Gametes have the unique potential to enter the sporophytic pathway, called androgenesis. The plants produced are usually haploid and recombinant due to the preceding meiosis and they can double their chromosome number to form doubled haploids, which are completely homozygous. Availability of the doubled haploids facilitates mapping the genes of agronomically important traits, shortening the time of the breeding process required to produce new hybrids and homozygous varieties, and saving the time and cost for inbreeding. This study aimed to test the feasibility of using isolated and in vitro cultured immature cassava (Manihot esculenta) microspores to reprogramme and initiate sporophytic development. Different culture media and different concentrations of two ion components (Cu(2+) and Fe(2+)) were tested in two genotypes of cassava. External structural changes, nuclear divisions and cellular changes during reprogramming were analysed by scanning electron microscopy, by staining with 4',6-diamidino-2-phenylindole, and through classical histology and transmission electron microscopy. In two cassava genotypes, different developmental stages of microspores were found to initiate sporophytic cell divisions, that is, with tetrads of TMS 60444 and with mid or late uni-nucleate microspores of SM 1219-9. In the modified NLN medium (NLNS), microspore enlargements were observed. The medium supplemented with either sodium ferrous ethylene-diamine-tetraacetic acid (NaFeEDTA) or CuSO4·5H2O induced sporophytic cell division in both genotypes. A low frequency of the reprogramming and the presence of non-responsive microspores among the responsive ones in tetrads were found to be related to the viability and exine formation of the microspores. The present study clearly demonstrated that reprogramming occurs much faster in isolated microspore culture than in anther culture. This paves the way for the development of an efficient technique for the production of homozygous lines in cassava. This is the first ever detailed report of microspore reprogramming at the tetrad stage and the first report of microspore embryogenesis induction in cassava with detailed evidence. PMID:24887001

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 so...

  11. Nutritional composition of “gari” analog produced from cassava (Manihot esculenta) and cocoyam (Colocasia esculenta) tuber

    PubMed Central

    Bamidele, Oluwaseun P; Ogundele, Femi G; Ojubanire, Basirat A; Fasogbon, Mofoluwaso B; Bello, Olayide W

    2014-01-01

    Physicochemical properties ofgari analog produced from coprocessing of Cassava (Manihot esculenta Crantz) and Cocoyam (Colocasia esculenta) were investigated. Cassava tuber and cocoyam were coprocessed at different percentages before frying separately. Proximate composition, mineral content, antinutritional factors, and sensory evaluation of various samples were determined. The results showed that the moisture content of all the samples was in the same range (7.28 ± 0.30 to 7.78 ± 0.14%). The protein content (1.57 ± 0.14 to 4.43 ± 0.16), ash (1.89 ± 0.10 to 2.15 ± 0.30), and crude fiber (1.53 ± 0.50 to 2.19 ± 0.10%) showed a significant increase with increase in the level of cocoyam substitution. The fat and carbohydrate content decreased with an increase in cocoyam level. The mineral contents of the samples increased with an increase in cocoyam content with sample F having the highest value of potassium, followed by samples E and D (68 mg/100 g, 35 mg/100 g, and 24 mg/100 g). The antinutritional factors of all the samples were at very low concentration while samples B, C, and D competed favorably with sample A (control) in sensory evaluation. In conclusion, coprocessing of cassava and cocoyam improved the nutritional quality of thegari produced with high level of acceptance from the taste panelist. PMID:25493189

  12. A geographic distribution database of Mononychellus mites (Acari, Tetranychidae) on cassava (Manihot esculenta)

    PubMed Central

    Vásquez-Ordóñez, Aymer Andrés; Parsa, Soroush

    2014-01-01

    Abstract The genus Mononychellus is represented by 28 herbivorous mites. Some of them are notorious pests of cassava (Manihot esculenta Crantz), a primary food crop in the tropics. With the exception of Mononychellus tanajoa (Bondar), their geographic distribution is not widely known. This article therefore reports observational and specimen-based occurrence data of Mononychellus species associated with cassava. The dataset consists of 1,513 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT’s Arthropod Reference Collection (CIATARC). Most of the records are from the genus’ native range in South America and were documented between 1980 and 2000. Approximately 61% of the records belong to M. tanajoa, 25% to M. caribbeanae (McGregor), 10% to M. mcgregori (Flechtmann and Baker) and 2% to M. planki (McGregor). The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF). PMID:24899828

  13. Pathological and Molecular Characterization of Xanthomonas campestris Strains Causing Diseases of Cassava (Manihot esculenta)

    PubMed Central

    Verdier, Valérie; Boher, Bernard; Maraite, Henri; Geiger, Jean-Paul

    1994-01-01

    Fifty-one strains representing Xanthomonas campestris pv. manihotis and cassavae and different pathovars occurring on plants of the family Euphorbiaceae were characterized by ribotyping with a 16S+23S rRNA probe of Escherichia coli and by restriction fragment length polymorphism analysis with a plasmid probe from X. campestris pv. manihotis. Pathogenicity tests were performed on cassava (Manihot esculenta). Histological comparative studies were conducted on strains of two pathovars of X. campestris (vascular and mesophyllic) that attack cassava. Our results indicated that X. campestris pv. manihotis and cassavae have different modes of action in the host and supplemented the taxonomic data on restriction fragment length polymorphism that clearly separate the two pathovars. The plasmid probe could detect multiple restriction fragment length polymorphisms among strains of the pathovar studied. Ribotyping provides a useful tool for rapid identification of X. campestris pathovars on cassava. Images PMID:16349463

  14. Inter-retrotransposon-amplified polymorphism markers for germplasm characterization in Manihot esculenta (Euphorbiaceae).

    PubMed

    Oliveira-Silva, A M; Silva, G F; Dias, M C; Clement, C R; Sousa, N R

    2014-01-01

    Manioc, Manihot esculenta, is economically important in many tropical and subtropical countries. The genetic variability of the species has not been fully explored, and new information may help expand its use. Molecular markers based on retrotransposons have good potential for analysis of genetic diversity given their abundance in the genome. Eight long terminal repeat retrotransposons were selected for the development of inter-retrotransposon-amplified polymorphism markers. To test these primers, we analyzed 32 varieties from Anori, 30 from Manicoré and 10 Mandiocabas from the Manioc Germplasm Bank at Embrapa Western Amazonia. The six informative primer pairs yielded 20- 60 polymorphic bands, averaging 92% polymorphism (51.7-98.4) and 0.37 heterozygosity (0.17 to 0.40), with a Shannon information index of 0.54 (0.26-0.59). These markers can be used to explore the genetic diversity of manioc. PMID:24938466

  15. Cassava (Manihot esculenta Krantz) genome harbors KNOX genes differentially expressed during storage root development.

    PubMed

    Guo, D; Li, H L; Tang, X; Peng, S Q

    2014-01-01

    In plants, homeodomain proteins play a critical role in regulating various aspects of plant growth and development. KNOX proteins are members of the homeodomain protein family. The KNOX transcription factors have been reported from Arabidopsis, rice, and other higher plants. The recent publication of the draft genome sequence of cassava (Manihot esculenta Krantz) has allowed a genome-wide search for M. esculenta KNOX (MeKNOX) transcription factors and the comparison of these positively identified proteins with their homologs in model plants. In the present study, we identified 12 MeKNOX genes in the cassava genome and grouped them into two distinct subfamilies based on their domain composition and phylogenetic analysis. Furthermore, semi-quantitative reverse transcription polymerase chain reaction analysis was performed to elucidate the expression profiles of these genes in different tissues and during various stages of root development. The analysis of MeKNOX expression profiles of indicated that 12 MeKNOX genes display differential expressions either in their transcript abundance or expression patterns. PMID:25526192

  16. Genetic characterization of cassava (Manihot esculenta) landraces in Brazil assessed with simple sequence repeats

    PubMed Central

    2009-01-01

    Based on nine microsatellite loci, the aim of this study was to appraise the genetic diversity of 42 cassava (Manihot esculenta) landraces from selected regions in Brazil, and examine how this variety is distributed according to origin in several municipalities in the states of Minas Gerais, São Paulo, Mato Grosso do Sul, Amazonas and Mato Grosso. High diversity values were found among the five above-mentioned regions, with 3.3 alleles per locus on an average, a high percentage of polymorphic loci varying from 88.8% to 100%, an average of 0.265 for observed heterozygosity and 0.570 for gene diversity. Most genetic diversity was concentrated within the regions themselves (HS = 0.52). Cluster analysis and principal component based scatter plotting showed greater similarity among landraces from São Paulo, Mato Grosso do Sul and Amazonas, whereas those from Minas Gerais were clustered into a sub-group within this group. The plants from Mato Grosso, mostly collected in the municipality of General Carneiro, provided the highest differentiation. The migration of human populations is one among the possible reasons for this closer resemblance or greater disparity among plants from the various regions. PMID:21637653

  17. Structure determinants of substrate specificity of hydroxynitrile lyase from Manihot esculenta

    PubMed Central

    Lauble, Hanspeter; Miehlich, Burkhard; Förster, Siegfried; Kobler, Christoph; Wajant, Harald; Effenberger, Franz

    2002-01-01

    Tryptophan 128 of hydroxynitrile lyase of Manihot esculenta (MeHNL) covers a significant part of a hydrophobic channel that gives access to the active site of the enzyme. This residue was therefore substituted in the mutant MeHNL-W128A by alanine to study its importance for the substrate specificity of the enzyme. Wild-type MeHNL and MeHNL-W128A showed comparable activity on the natural substrate acetone cyanohydrin (53 and 40 U/mg, respectively). However, the specific activities of MeHNL-W128A for the unnatural substrates mandelonitrile and 4-hydroxymandelonitrile are increased 9-fold and ∼450-fold, respectively, compared with the wild-type MeHNL. The crystal structure of the MeHNL-W128A substrate-free form at 2.1 Å resolution indicates that the W128A substitution has significantly enlarged the active-site channel entrance, and thereby explains the observed changes in substrate specificity for bulky substrates. Surprisingly, the MeHNL-W128A–4-hydroxybenzaldehyde complex structure at 2.1 Å resolution shows the presence of two hydroxybenzaldehyde molecules in a sandwich type arrangement in the active site with an additional hydrogen bridge to the reacting center. PMID:11742123

  18. Evaluation of antioxidant activity of Manihot esculenta Crantz in wistar rats

    PubMed Central

    Bahekar, Satish Eknath; Kale, Ranjana Sushil

    2016-01-01

    Aims: The study aimed to explore the antioxidant activity of ethanolic leaf extract of Manihot esculenta Crantz leaves (MEC) in wistar rats. Materials and Methods: Ethanolic extract of MEC leaves in the doses of 50 mg/kg, 100 mg/kg, and 200 mg/kg were used in wistar rats of either sex. The oxidative stress was produced by overdose of acetaminophen and estimation of serum concentration of various enzymes such as malonaldehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), and catalase (CAT) were measured by standard biochemical methods. Silymarin (100 mg/kg) was used as a standard drug for assessment of antioxidant status. Statistical Analysis Used: Results were analyzed by one-way analysis of variance followed by Student's unpaired t-test. Results: When compared with the standard antioxidant silymarin, MEC extract did not exhibit antioxidant activity in terms of MDA level reduction. However, it significantly increased serum levels of the antioxidant enzymes (SOD, GSH, and CAT) exerting a potent antioxidant effect in a graded manner. Conclusions: The observed results suggest that MEC could be a potential source of antioxidants. However, further studies are required to explore this therapeutic property of plant. PMID:27134463

  19. Meristem micropropagation of cassava (Manihot esculenta) evokes genome-wide changes in DNA methylation

    PubMed Central

    Kitimu, Shedrack R.; Taylor, Julian; March, Timothy J.; Tairo, Fred; Wilkinson, Mike J.; Rodríguez López, Carlos M.

    2015-01-01

    There is great interest in the phenotypic, genetic and epigenetic changes associated with plant in vitro culture known as somaclonal variation. In vitro propagation systems that are based on the use of microcuttings or meristem cultures are considered analogous to clonal cuttings and so widely viewed to be largely free from such somaclonal effects. In this study, we surveyed for epigenetic changes during propagation by meristem culture and by field cuttings in five cassava (Manihot esculenta) cultivars. Principal Co-ordinate Analysis of profiles generated by methylation-sensitive amplified polymorphism revealed clear divergence between samples taken from field-grown cuttings and those recovered from meristem culture. There was also good separation between the tissues of field samples but this effect was less distinct among the meristem culture materials. Application of methylation-sensitive Genotype by sequencing identified 105 candidate epimarks that distinguish between field cutting and meristem culture samples. Cross referencing the sequences of these epimarks to the draft cassava genome revealed 102 sites associated with genes whose homologs have been implicated in a range of fundamental biological processes including cell differentiation, development, sugar metabolism, DNA methylation, stress response, photosynthesis, and transposon activation. We explore the relevance of these findings for the selection of micropropagation systems for use on this and other crops. PMID:26322052

  20. Meristem micropropagation of cassava (Manihot esculenta) evokes genome-wide changes in DNA methylation.

    PubMed

    Kitimu, Shedrack R; Taylor, Julian; March, Timothy J; Tairo, Fred; Wilkinson, Mike J; Rodríguez López, Carlos M

    2015-01-01

    There is great interest in the phenotypic, genetic and epigenetic changes associated with plant in vitro culture known as somaclonal variation. In vitro propagation systems that are based on the use of microcuttings or meristem cultures are considered analogous to clonal cuttings and so widely viewed to be largely free from such somaclonal effects. In this study, we surveyed for epigenetic changes during propagation by meristem culture and by field cuttings in five cassava (Manihot esculenta) cultivars. Principal Co-ordinate Analysis of profiles generated by methylation-sensitive amplified polymorphism revealed clear divergence between samples taken from field-grown cuttings and those recovered from meristem culture. There was also good separation between the tissues of field samples but this effect was less distinct among the meristem culture materials. Application of methylation-sensitive Genotype by sequencing identified 105 candidate epimarks that distinguish between field cutting and meristem culture samples. Cross referencing the sequences of these epimarks to the draft cassava genome revealed 102 sites associated with genes whose homologs have been implicated in a range of fundamental biological processes including cell differentiation, development, sugar metabolism, DNA methylation, stress response, photosynthesis, and transposon activation. We explore the relevance of these findings for the selection of micropropagation systems for use on this and other crops. PMID:26322052

  1. Development of retrotransposon-based markers IRAP and REMAP for cassava (Manihot esculenta).

    PubMed

    Kuhn, B C; Mangolin, C A; Souto, E R; Vicient, C M; Machado, M F P S

    2016-01-01

    Retrotransposons are abundant in the genomes of plants. In the present study, inter-retrotransposon amplified polymorphism (IRAP) and retrotransposon-microsatellite amplified polymorphism (REMAP) markers were developed for the cassava genome (Manihot esculenta Crantz). Four cassava cultivars (Fécula Branca, IPR-União, Olho Junto, and Tamboara, two samples per cultivar) were used to obtain IRAP and REMAP fingerprints. Twelve designed primers were amplified alone and in combinations. The 42 IRAP/REMAP primer combinations amplified 431 DNA segments (bands; markers) of which 36 (8.36%) were polymorphic. The largest number of informative markers (16) was detected using the primers AYF2 and AYF2xAYF4. The number of bands for each primer varied from 3 to 16, with an average of 10.26 amplified segments per primer. The size of the amplified products ranged between 100 and 7000 bp. The AYF2 primer generated the highest number of amplified segments and showed the highest number of polymorphic bands (68.75%). Two samples of each cassava cultivar were used to illustrate the usefulness and the polymorphism of IRAP/REMAP markers. IRAP and REMAP markers produced a high number of reproducible bands, and might be informative and reliable for investigation of genetic diversity and relationships among cassava cultivars. PMID:27173210

  2. Genetic fidelity and variability of micropropagated cassava plants (Manihot esculenta Crantz) evaluated using ISSR markers.

    PubMed

    Vidal, Á M; Vieira, L J; Ferreira, C F; Souza, F V D; Souza, A S; Ledo, C A S

    2015-01-01

    Molecular markers are efficient for assessing the genetic fidelity of various species of plants after in vitro culture. In this study, we evaluated the genetic fidelity and variability of micropropagated cassava plants (Manihot esculenta Crantz) using inter-simple sequence repeat markers. Twenty-two cassava accessions from the Embrapa Cassava & Fruits Germplasm Bank were used. For each accession, DNA was extracted from a plant maintained in the field and from 3 plants grown in vitro. For DNA amplification, 27 inter-simple sequence repeat primers were used, of which 24 generated 175 bands; 100 of those bands were polymorphic and were used to study genetic variability among accessions of cassava plants maintained in the field. Based on the genetic distance matrix calculated using the arithmetic complement of the Jaccard's index, genotypes were clustered using the unweighted pair group method using arithmetic averages. The number of bands per primer was 2-13, with an average of 7.3. For most micropropagated accessions, the fidelity study showed no genetic variation between plants of the same accessions maintained in the field and those maintained in vitro, confirming the high genetic fidelity of the micropropagated plants. However, genetic variability was observed among different accessions grown in the field, and clustering based on the dissimilarity matrix revealed 7 groups. Inter-simple sequence repeat markers were efficient for detecting the genetic homogeneity of cassava plants derived from meristem culture, demonstrating the reliability of this propagation system. PMID:26214457

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

    PubMed

    Soto-Blanco, Benito; Górniak, Silvana Lima

    2010-07-01

    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

  4. Somatic embryogenesis and plant regeneration of cassava (Manihot esculenta Crantz) landraces from Cameroon.

    PubMed

    Mongomake, Kone; Doungous, Oumar; Khatabi, Behnam; Fondong, Vincent N

    2015-01-01

    A procedure to regenerate cassava (Manihot esculenta Crantz) cultivars from Cameroon via somatic embryogenesis (SE) was developed. Shoot apical meristems and immature leaf lobes were used as explants on Murashige and Skoog (MS) basal medium containing 33 or 50 µM of the auxins Picloram (Pic), 2,4-Dichlorophenoxyacetic acid (2,4-D), Dicamba (Dic), and α-Naphthalene acetic acid. Cultivar performance was assessed using SE and number of somatic embryos produced. Overall, the frequency of primary somatic embryogenesis (PSE) and the mean number of somatic embryos produced varied considerably with genotype, type of auxin and concentration tested. For example, cultivar (cv.) Ngan Mbada showed the best performance on MS medium supplemented with 50 µM Pic with a SE frequency of 40 % and an average number of somatic embryos of 90. The second best performance was recorded in cv. Local Red on MS medium supplemented with 33 µM 2,4-D, where the SE frequency was 40 % and an average number of somatic embryos of 60.5. Cultivar Ekona Red recorded the best performance on medium supplemented with 50 µM Pic showing a SE frequency of 47 % and an average number of somatic embryos of 45. We further examined secondary and cyclic somatic embryogenesis (SSE, CSE) and both were also observed to vary with genotype, however, both exhibited significantly higher frequencies of SE compared with PSE. SE started to decline at the fourth cycle of embryogenesis. Examination of organogenesis showed that shoot bud induction from green cotyledons varied across cultivars and benzylaminopurine was shown to outperform Thidiazuron in the ability to induce organogenesis. Furthermore, the frequencies of bud induction were identical under light and dark conditions. Finally, regenerated plants grew easily in the greenhouse with 90-100 % survival rate and did not display detectable variation in morphology. PMID:26361578

  5. Cyanide and Aflatoxin Loads of Processed Cassava (Manihot esculenta) Tubers (Garri) in Njaba, Imo State, Nigeria

    PubMed Central

    Chikezie, Paul Chidoka; Ojiako, Okey A.

    2013-01-01

    Objectives: The present study sought to investigate the role of palm oil, in conjunction with the duration of fermentation, on cyanide and aflatoxin (AFT) loads of processed cassava tubers (Garri). Materials and Methods: Matured cassava (Manihot esculenta Crantz) tubers were harvested from three different locations (Akunna, Mkporo-Oji and Durungwu) in Njaba Local Government Area, Imo State, Nigeria. The cassava tubers were processed into Garri according to standard schemes with required modifications and measured for cyanide content using titrimetric methods. Samples of Garri for determination of AFT levels were stored for 30 days before the commencement of spectrophotometric analysis. Results: Cyanide content of peeled cassava tubers was within the range of 4.07 ± 0.16-5.20 ± 0.19 mg hydrocyanic acid (HCN) equivalent/100 g wet weight, whereas the various processed cassava tubers was within the range of 1.44 ± 0.34-3.95 ± 0.23 mg HCN equivalents/100 g. For the 48 h fermentation scheme, Garri treated with palm oil exhibited marginal reduction in cyanide contents by 0.96%, 3.52% and 3.69%, whereas 4 h fermentation scheme is in concurrence with palm oil treatment caused 4.42%, 7.47% and 5.15% elimination of cyanide contents compared with corresponding untreated Garri samples (P > 0.05). Levels of AFT of the various Garri samples ranged between 0.26 ± 0.07 and 0.55 ± 0.04 ppb/100 g. There was no significant difference (P > 0.05) in AFT levels among the various samples in relation to their corresponding sources. Conclusion: The present study showed that the 48 h fermentation scheme for Garri production caused significant (P < 0.05) reduction, but did not obliterate the cyanide content of cassava tubers. Conversely, the 48 h fermentation scheme promoted the elevation of AFT levels, but was relatively reduced in Garri samples treated with palm oil. PMID:24403736

  6. Comparative Proteome Analysis of the Tuberous Roots of Six Cassava (Manihot esculenta) Varieties Reveals Proteins Related to Phenotypic Traits.

    PubMed

    Schmitz, Gabriela Justamante Händel; de Magalhães Andrade, Jonathan; Valle, Teresa Losada; Labate, Carlos Alberto; do Nascimento, João Roberto Oliveira

    2016-04-27

    Cassava (Manihot esculenta Crantz) is a staple food and an important source of starch, and the attributes of its tuberous root largely depend on the variety. The proteome of cassava has been investigated; however, to date, no study has focused on varieties that reveal the molecular basis of phenotypical characteristics. Therefore, we aimed to compare the proteome of the tuberous roots of six cassava varieties that differed in carbohydrates, carotenoids, and resistance to diseases, among other attributes. Two-dimensional gels showed 146 differential spots between the varieties, and the functional roles of some differential proteins were correlated to phenotypic characteristics of the varieties, such as the amount of carbohydrates or carotenoids and the resistance to biotic or abiotic stresses. The results obtained here highlight elements that might help to direct the improvement of new cultivars of cassava, which is an economically and socially relevant crop worldwide. PMID:26982619

  7. Variability of chloroplast DNA and nuclear ribosomal DNA in cassava (Manihot esculenta Crantz) and its wild relatives.

    PubMed

    Fregene, M A; Vargas, J; Ikea, J; Angel, F; Tohme, J; Asiedu, R A; Akoroda, M O; Roca, W M

    1994-11-01

    Chloroplast DNA (cp) and nuclear ribosomal DNA (rDNA) variation was investigated in 45 accessions of cultivated and wild Manihot species. Ten independent mutations, 8 point mutations and 2 length mutations were identified, using eight restriction enzymes and 12 heterologous cpDNA probes from mungbean. Restriction fragment length polymorphism analysis defined nine distinct chloroplast types, three of which were found among the cultivated accessions and six among the wild species. Cladistic analysis of the cpDNA data using parsimony yielded a hypothetical phylogeny of lineages among the cpDNAs of cassava and its wild relatives that is congruent with morphological evolutionary differentiation in the genus. The results of our survey of cpDNA, together with rDNA restriction site change at the intergenic spacer region and rDNA repeat unit length variation (using rDNA cloned fragments from taro as probe), suggest that cassava might have arisen from the domestication of wild tuberous accessions of some Manihot species, followed by intensive selection. M. esculenta subspp flabellifolia is probably a wild progenitor. Introgressive hybridization with wild forms and pressures to adapt to the widely varying climates and topography in which cassava is found might have enhanced the crop's present day variability. PMID:24178017

  8. High-Resolution Linkage Map and Chromosome-Scale Genome Assembly for Cassava (Manihot esculenta Crantz) from 10 Populations

    PubMed Central

    2014-01-01

    Cassava (Manihot esculenta Crantz) is a major staple crop in Africa, Asia, and South America, and its starchy roots provide nourishment for 800 million people worldwide. Although native to South America, cassava was brought to Africa 400–500 years ago and is now widely cultivated across sub-Saharan Africa, but it is subject to biotic and abiotic stresses. To assist in the rapid identification of markers for pathogen resistance and crop traits, and to accelerate breeding programs, we generated a framework map for M. esculenta Crantz from reduced representation sequencing [genotyping-by-sequencing (GBS)]. The composite 2412-cM map integrates 10 biparental maps (comprising 3480 meioses) and organizes 22,403 genetic markers on 18 chromosomes, in agreement with the observed karyotype. We used the map to anchor 71.9% of the draft genome assembly and 90.7% of the predicted protein-coding genes. The chromosome-anchored genome sequence will be useful for breeding improvement by assisting in the rapid identification of markers linked to important traits, and in providing a framework for genomic selection-enhanced breeding of this important crop. PMID:25504737

  9. High-resolution linkage map and chromosome-scale genome assembly for cassava (Manihot esculenta Crantz) from 10 populations.

    PubMed

    2014-01-01

    Cassava (Manihot esculenta Crantz) is a major staple crop in Africa, Asia, and South America, and its starchy roots provide nourishment for 800 million people worldwide. Although native to South America, cassava was brought to Africa 400-500 years ago and is now widely cultivated across sub-Saharan Africa, but it is subject to biotic and abiotic stresses. To assist in the rapid identification of markers for pathogen resistance and crop traits, and to accelerate breeding programs, we generated a framework map for M. esculenta Crantz from reduced representation sequencing [genotyping-by-sequencing (GBS)]. The composite 2412-cM map integrates 10 biparental maps (comprising 3480 meioses) and organizes 22,403 genetic markers on 18 chromosomes, in agreement with the observed karyotype. We used the map to anchor 71.9% of the draft genome assembly and 90.7% of the predicted protein-coding genes. The chromosome-anchored genome sequence will be useful for breeding improvement by assisting in the rapid identification of markers linked to important traits, and in providing a framework for genomic selection-enhanced breeding of this important crop. PMID:25504737

  10. Domestication Syndrome Is Investigated by Proteomic Analysis between Cultivated Cassava (Manihot esculenta Crantz) and Its Wild Relatives

    PubMed Central

    An, Feifei; Chen, Ting; Stéphanie, Djabou Mouafi Astride; Li, Kaimian; Li, Qing X.; Carvalho, Luiz J. C. B.; Tomlins, Keith; Li, Jun; Gu, Bi; Chen, Songbi

    2016-01-01

    Cassava (Manihot esculenta Crantz) wild relatives remain a largely untapped potential for genetic improvement. However, the domestication syndrome phenomena from wild species to cultivated cassava remain poorly understood. The analysis of leaf anatomy and photosynthetic activity showed significantly different between cassava cultivars SC205, SC8 and wild relative M. esculenta ssp. Flabellifolia (W14). The dry matter, starch and amylose contents in the storage roots of cassava cultivars were significantly more than that in wild species. In order to further reveal the differences in photosynthesis and starch accumulation of cultivars and wild species, the globally differential proteins between cassava SC205, SC8 and W14 were analyzed using 2-DE in combination with MALDI-TOF tandem mass spectrometry. A total of 175 and 304 proteins in leaves and storage roots were identified, respectively. Of these, 122 and 127 common proteins in leaves and storage roots were detected in SC205, SC8 and W14, respectively. There were 11, 2 and 2 unique proteins in leaves, as well as 58, 9 and 12 unique proteins in storage roots for W14, SC205 and SC8, respectively, indicating proteomic changes in leaves and storage roots between cultivated cassava and its wild relatives. These proteins and their differential regulation across plants of contrasting leaf morphology, leaf anatomy pattern and photosynthetic related parameters and starch content could contribute to the footprinting of cassava domestication syndrome. We conclude that these global protein data would be of great value to detect the key gene groups related to cassava selection in the domestication syndrome phenomena. PMID:27023871

  11. Domestication Syndrome Is Investigated by Proteomic Analysis between Cultivated Cassava (Manihot esculenta Crantz) and Its Wild Relatives.

    PubMed

    An, Feifei; Chen, Ting; Stéphanie, Djabou Mouafi Astride; Li, Kaimian; Li, Qing X; Carvalho, Luiz J C B; Tomlins, Keith; Li, Jun; Gu, Bi; Chen, Songbi

    2016-01-01

    Cassava (Manihot esculenta Crantz) wild relatives remain a largely untapped potential for genetic improvement. However, the domestication syndrome phenomena from wild species to cultivated cassava remain poorly understood. The analysis of leaf anatomy and photosynthetic activity showed significantly different between cassava cultivars SC205, SC8 and wild relative M. esculenta ssp. Flabellifolia (W14). The dry matter, starch and amylose contents in the storage roots of cassava cultivars were significantly more than that in wild species. In order to further reveal the differences in photosynthesis and starch accumulation of cultivars and wild species, the globally differential proteins between cassava SC205, SC8 and W14 were analyzed using 2-DE in combination with MALDI-TOF tandem mass spectrometry. A total of 175 and 304 proteins in leaves and storage roots were identified, respectively. Of these, 122 and 127 common proteins in leaves and storage roots were detected in SC205, SC8 and W14, respectively. There were 11, 2 and 2 unique proteins in leaves, as well as 58, 9 and 12 unique proteins in storage roots for W14, SC205 and SC8, respectively, indicating proteomic changes in leaves and storage roots between cultivated cassava and its wild relatives. These proteins and their differential regulation across plants of contrasting leaf morphology, leaf anatomy pattern and photosynthetic related parameters and starch content could contribute to the footprinting of cassava domestication syndrome. We conclude that these global protein data would be of great value to detect the key gene groups related to cassava selection in the domestication syndrome phenomena. PMID:27023871

  12. Large-Scale SNP Discovery through RNA Sequencing and SNP Genotyping by Targeted Enrichment Sequencing in Cassava (Manihot esculenta Crantz)

    PubMed Central

    Pootakham, Wirulda; Shearman, Jeremy R.; Ruang-areerate, Panthita; Sonthirod, Chutima; Sangsrakru, Duangjai; Jomchai, Nukoon; Yoocha, Thippawan; Triwitayakorn, Kanokporn; Tragoonrung, Somvong; Tangphatsornruang, Sithichoke

    2014-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crop species being the main source of dietary energy in several countries. Marker-assisted selection has become an essential tool in plant breeding. Single nucleotide polymorphism (SNP) discovery via transcriptome sequencing is an attractive strategy for genome complexity reduction in organisms with large genomes. We sequenced the transcriptome of 16 cassava accessions using the Illumina HiSeq platform and identified 675,559 EST-derived SNP markers. A subset of those markers was subsequently genotyped by capture-based targeted enrichment sequencing in 100 F1 progeny segregating for starch viscosity phenotypes. A total of 2,110 non-redundant SNP markers were used to construct a genetic map. This map encompasses 1,785 cM and consists of 19 linkage groups. A major quantitative trait locus (QTL) controlling starch pasting properties was identified and shown to coincide with the QTL previously reported for this trait. With a high-density SNP-based linkage map presented here, we also uncovered a novel QTL associated with starch pasting time on LG 10. PMID:25551642

  13. UV-visible scanning spectrophotometry and chemometric analysis as tools for carotenoids analysis in cassava genotypes (Manihot esculenta Crantz).

    PubMed

    Moresco, Rodolfo; Uarrota, Virgílio Gavicho; Pereira, Aline; Tomazzoli, Maíra Maciel; Nunes, Eduardo da C; Peruch, Luiz Augusto Martins; Gazzola, Jussara; Costa, Christopher; Rocha, Miguel; Maraschin, Marcelo

    2015-01-01

    In this study, the metabolomics characterization focusing on the carotenoid composition of ten cassava (Manihot esculenta) genotypes cultivated in southern Brazil by UV-visible scanning spectrophotometry and reverse phase-high performance liquid chromatography was performed. Cassava roots rich in β-carotene are an important staple food for populations with risk of vitamin A deficiency. Cassava genotypes with high pro-vitamin A activity have been identified as a strategy to reduce the prevalence of deficiency of this vitamin. The data set was used for the construction of a descriptive model by chemometric analysis. The genotypes of yellow-fleshed roots were clustered by the higher concentrations of cis-β-carotene and lutein. Inversely, cream-fleshed roots genotypes were grouped precisely due to their lower concentrations of these pigments, as samples rich in lycopene (red-fleshed) differed among the studied genotypes. The analytical approach (UV-Vis, HPLC, and chemometrics) used showed to be efficient for understanding the chemodiversity of cassava genotypes, allowing to classify them according to important features for human health and nutrition. PMID:26673931

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

    PubMed Central

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

    2012-01-01

    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. PMID:23346343

  15. In vitro Cultured Primary Roots Derived from Stem Segments of Cassava (Manihot esculenta) Can Behave Like Storage Organs

    PubMed Central

    Medina, Ricardo D.; Faloci, Mirta M.; Gonzalez, Ana M.; Mroginski, Luis A.

    2007-01-01

    Background and Aims Cassava (Manihot esculenta) has three adventitious root types: primary and secondary fibrous roots, and storage roots. Different adventitious root types can also regenerate from in vitro cultured segments. The aim of this study was to investigate aspects of in vitro production of storage roots. Methods Morphological and anatomical analyses were performed to identify and differentiate each root type. Twenty-nine clones were assayed to determine the effect of genotype on the capacity to form storage roots in vitro. The effects of cytokinins and auxins on the formation of storage roots in vitro were also examined. Key Results Primary roots formed in vitro and in vivo had similar tissue kinds; however, storage roots formed in vitro exhibited physiological specialization for storing starch. The only consistent diagnostic feature between secondary fibrous and storage roots was their functional differentiation. Anatomical analysis of the storage roots formed in vitro showed that radial expansion as a consequence of massive proliferation and enlargement of parenchymatous cells occurred in the middle cortex, but not from cambial activity as in roots formed in vivo. Cortical expansion could be related to dilatation growth favoured by hormone treatments. Starch deposition of storage roots formed in vitro was confined to cortical tissue and occurred earlier than in storage roots formed in vivo. Auxin and cytokinin supplementation were absolutely required for in vitro storage root regeneration; these roots were not able to develop secondary growth, but formed a tissue competent for starch storing. MS medium with 5 % sucrose plus 0·54 μm 1-naphthaleneacetic acid and 0·44 μm 6-benzylaminopurine was one of the most effective in stimulating the storage root formation. Genotypes differed significantly in their capacity to produce storage roots in vitro. Storage root formation was considerably affected by the segment's primary position and strongly influenced by hormone treatments. Conclusions The storage root formation system reported here is a first approach to develop a tuberization model, and additional efforts are required to improve it. Although it was not possible to achieve root secondary growth, after this work it will be feasible to advance in some aspects of in vitro cassava tuberization. PMID:17267513

  16. Mechanistic aspects of cyanogenesis from active-site mutant Ser80Ala of hydroxynitrile lyase from Manihot esculenta in complex with acetone cyanohydrin

    PubMed Central

    Lauble, Hanspeter; Miehlich, Burkhard; Förster, Siegfried; Wajant, Harald; Effenberger, Franz

    2001-01-01

    The structure and function of hydroxynitrile lyase from Manihot esculenta (MeHNL) have been analyzed by X-ray crystallography and site-directed mutagenesis. The crystal structure of the MeHNL–S80A mutant enzyme has been refined to an R-factor of 18.0% against diffraction data to 2.1-Å resolution. The three-dimensional structure of the MeHNL–S80A–acetone cyanohydrin complex was determined at 2.2-Å resolution and refined to an R-factor of 18.7%. Thr11 and Cys81 involved in substrate binding have been substituted by Ala in site-directed mutagenesis. The kinetic measurements of these mutant enzymes are presented. Combined with structural data, the results support a mechanism for cyanogenesis in which His236 as a general base abstracts a proton from Ser80, thereby allowing proton transfer from the hydroxyl group of acetone cyanohydrin to Ser80. The His236 imidazolium cation then facilitates the leaving of the nitrile group by proton donating. PMID:11316882

  17. Increased expression of native cytosolic Cu/Zn superoxide dismutase and ascorbate peroxidase improves tolerance to oxidative and chilling stresses in cassava (Manihot esculenta Crantz)

    PubMed Central

    2014-01-01

    Background Cassava (Manihot esculenta Crantz) is a tropical root crop, and is therefore, extremely sensitive to low temperature; its antioxidative response is pivotal for its survival under stress. Timely turnover of reactive oxygen species (ROS) in plant cells generated by chilling-induced oxidative damages, and scavenging can be achieved by non-enzymatic and enzymatic reactions in order to maintain ROS homeostasis. Results Transgenic cassava plants that co-express cytosolic superoxide dismutase (SOD), MeCu/ZnSOD, and ascorbate peroxidase (APX), MeAPX2, were produced and tested for tolerance against oxidative and chilling stresses. The up-regulation of MeCu/ZnSOD and MeAPX2 expression was confirmed by the quantitative reverse transcriptase-polymerase chain reaction, and enzymatic activity analyses in the leaves of transgenic cassava plant lines with a single-transgene integration site. Upon exposure to ROS-generating agents, 100 μM ROS-generating reagent methyl viologen and 0.5 M H2O2, higher levels of enzymatic activities of SOD and APX were detected in transgenic plants than the wild type. Consequently, the oxidative stress parameters, such as lipid peroxidation, chlorophyll degradation and H2O2 synthesis, were lower in the transgenic lines than the wild type. Tolerance to chilling stress at 4°C for 2 d was greater in transgenic cassava, as observed by the higher levels of SOD, catalase, and ascorbate-glutathione cycle enzymes (e.g., APX, monodehydroascorbate reductase, dehydroascorbate reducatase and glutathione reductase) and lower levels of malondialdehyde content. Conclusions These results suggest that the expression of native cytosolic SOD and APX simultaneously activated the antioxidative defense mechanisms via cyclic ROS scavenging, thereby improving its tolerance to cold stress. PMID:25091029

  18. Validation of Reference Genes for Relative Quantitative Gene Expression Studies in Cassava (Manihot esculenta Crantz) by Using Quantitative Real-Time PCR

    PubMed Central

    Hu, Meizhen; Hu, Wenbin; Xia, Zhiqiang; Zhou, Xincheng; Wang, Wenquan

    2016-01-01

    Reverse transcription quantitative real-time polymerase chain reaction (real-time PCR, also referred to as quantitative RT-PCR or RT-qPCR) is a highly sensitive and high-throughput method used to study gene expression. Despite the numerous advantages of RT-qPCR, its accuracy is strongly influenced by the stability of internal reference genes used for normalizations. To date, few studies on the identification of reference genes have been performed on cassava (Manihot esculenta Crantz). Therefore, we selected 26 candidate reference genes mainly via the three following channels: reference genes used in previous studies on cassava, the orthologs of the most stable Arabidopsis genes, and the sequences obtained from 32 cassava transcriptome sequence data. Then, we employed ABI 7900 HT and SYBR Green PCR mix to assess the expression of these genes in 21 materials obtained from various cassava samples under different developmental and environmental conditions. The stability of gene expression was analyzed using two statistical algorithms, namely geNorm and NormFinder. geNorm software suggests the combination of cassava4.1_017977 and cassava4.1_006391 as sufficient reference genes for major cassava samples, the union of cassava4.1_014335 and cassava4.1_006884 as best choice for drought stressed samples, and the association of cassava4.1_012496 and cassava4.1_006391 as optimal choice for normally grown samples. NormFinder software recommends cassava4.1_006884 or cassava4.1_006776 as superior reference for qPCR analysis of different materials and organs of drought stressed or normally grown cassava, respectively. Results provide an important resource for cassava reference genes under specific conditions. The limitations of these findings were also discussed. Furthermore, we suggested some strategies that may be used to select candidate reference genes.

  19. Use of PCR-DHPLC with fluorescence detection for the characterization of the bacterial diversity during cassava (Manihot esculenta Crantz) fermentation.

    PubMed

    Kodama, C S; Cuadros-Orellana, S; Bandeira, C H M M; Graças, D A; Santos, A S; Silva, A

    2014-01-01

    Denaturing high-performance liquid chromatography (DHPLC) has been described as a suitable method to study DNA polymorphisms. Here, cassava (Manihot esculenta Crantz) fermentation liquor was examined using DHPLC analysis to characterize the bacterial diversity during the fermentation process. GC-clamped amplicons corresponding to a variable region of the bacterial community 16S rDNA were synthesized using polymerase chain reaction (PCR) and then resolved on a base-composition basis using preparative DHPLC. Eluate fractions were collected at random and used as a source of whole community DNA that could be used to determine the bacterial diversity. As a first approach, GC-clamps were removed from the eluted DNA fragments using PCR to avoid the possible bias these clamps could cause during the construction of clone libraries. As a second approach, a clone library of each eluate sample was constructed, preserving the GC-clamps of the DNA fragments. The first approach generated 132 bacterial rDNA sequences with an average size of 200 bp, 45% of which had similarity to unculturable or non-classified bacteria. The second approach produced 194 sequences identified as Proteobacteria (48%), uncultured or non-classified environmental bacteria (40%) and Firmicutes (12%). We detected a remarkably greater bacterial diversity using the first approach than the second approach. The DHPLC-PCR method allowed for the fast and non-laborious detection of a vast bacterial diversity that was associated with cassava fermentation, and we conclude that it is a promising alternative for the characterization of the overall microbial diversity in complex samples. PMID:24634228

  20. Transgenic rice expressing a cassava (Manihot esculenta Crantz) plasma membrane gene MePMP3-2 exhibits enhanced tolerance to salt and drought stresses.

    PubMed

    Yu, Y; Cui, Y C; Ren, C; Rocha, P S C F; Peng, M; Xu, G Y; Wang, M L; Xia, X J

    2016-01-01

    Plasma membrane proteolipid 3 (PMP3) is a class of small hydrophobic proteins found in many organisms including higher plants. Some plant PMP3 genes have been shown to respond to abiotic stresses and to participate in the processes of plant stress tolerance. In this study, we isolated the cassava (Manihot esculenta Crantz) MePMP3-2 gene and functionally characterized its role in tolerance to abiotic stress by expressing it in rice (Oryza sativa L.). MePMP3-2 encodes a 77-amino acid protein belonging to a subgroup of plant PMP3s that have long hydrophylic C-terminal tails of unknown function. In silico analysis and co-localization studies indicated that MePMP3-2 is a plasma membrane protein with two transmembrane domains, similar to other PMP3s. In cassava leaves, MePMP3-2 expression was up-regulated by salt and drought stresses. Heterologous constitutive expression of MePMP3-2 in rice did not alter plant growth and development but increased tolerance to salt and drought stresses. In addition, under stress conditions MePMP3-2 transgenic plants accumulated less malondialdehyde, had increased levels of proline, and exhibited greater up-regulation of the stress-related genes OsProT and OsP5CS, but led to only minor changes in OsDREB2A and OsLEA3 expression. These findings indicate that MePMP3-2 may play an important role in salt and drought stress tolerance in transgenic rice. PMID:26909954

  1. Inversion induced Manihot esculenta stem tubers express key tuberization genes; Mec1, RZF, SuSy1 and PIN2.

    PubMed

    Bowrin, Valerie; Sutton, Fedora

    2016-01-01

    Cassava (M. esculenta) gives rise to unique underground stem tubers when stem cuttings are planted in an inverted orientation. The nutritional profile of the stem and root tubers were similar except for protein content which was higher in stem than in root tubers. RT-PCR revealed that several key genes (Mec1, RZF, SuSy1 and PIN2) involved in root tuberization were also expressed in these stem tubers. At five weeks post planting, these genes were expressed in roots and underground stems as in the mature tubers. However at 15 weeks post planting, they were expressed in both root and stem tubers but not in adventitious roots or in the non-tuberized stems. Expression of, the root auxin efflux carrier gene PIN2 in the stem tubers indicate a role for auxin in the stem tuberization process. PMID:26785907

  2. Concentrations of arsenic, copper, cobalt, lead and zinc in cassava (Manihot esculenta Crantz) growing on uncontaminated and contaminated soils of the Zambian Copperbelt

    NASA Astrophysics Data System (ADS)

    Kříbek, B.; Majer, V.; Knésl, I.; Nyambe, I.; Mihaljevič, M.; Ettler, V.; Sracek, O.

    2014-11-01

    The concentrations of arsenic (As), copper (Cu), cobalt (Co), lead (Pb) and zinc (Zn) in washed leaves and washed and peeled tubers of cassava (Manihot esculenta Crantz, Euphorbiaceae) growing on uncontaminated and contaminated soils of the Zambian Copperbelt mining district have been analyzed. An enrichment index (EI) was used to distinguish between contaminated and uncontaminated areas. This index is based on the average ratio of the actual and median concentration of the given contaminants (As, Co, Cu, mercury (Hg), Pb and Zn) in topsoil. The concentrations of copper in cassava leaves growing on contaminated soils reach as much as 612 mg kg-1 Cu (total dry weight [dw]). Concentrations of copper in leaves of cassava growing on uncontaminated soils are much lower (up to 252 mg kg-1 Cu dw). The concentrations of Co (up to 78 mg kg-1 dw), As (up to 8 mg kg-1 dw) and Zn (up to 231 mg kg-1 dw) in leaves of cassava growing on contaminated soils are higher compared with uncontaminated areas, while the concentrations of lead do not differ significantly. The concentrations of analyzed chemical elements in the tubers of cassava are much lower than in its leaves with the exception of As. Even in strongly contaminated areas, the concentrations of copper in the leaves and tubers of cassava do not exceed the daily maximum tolerance limit of 0.5 mg kg-1/human body weight (HBW) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The highest tolerable weekly ingestion of 0.025 mg kg-1/HBW for lead and the highest tolerable weekly ingestion of 0.015 mg kg-1/HBW for arsenic are exceeded predominantly in the vicinity of smelters. Therefore, the preliminary assessment of dietary exposure to metals through the consumption of uncooked cassava leaves and tubers has been identified as a moderate hazard to human health. Nevertheless, as the surfaces of leaves are strongly contaminated by metalliferous dust in the polluted areas, there is still a potential hazard of ingesting dangerous levels of copper, lead and arsenic if dishes are prepared with poorly washed foliage.

  3. Physical localization of molecular markers and assignment of the 15th linkage group to chromosome 11 of the karyotype in cassava (Manihot esculenta Crantz) by primed in situ labeling.

    PubMed

    Wang, Y; Wang, J F; Yin, H; Gao, H Q; Zhuang, N S; Liu, J P

    2015-01-01

    Physical localization of molecular markers and assignment of the 15th linkage group to chromosome 11 of the karyotype in cassava (Manihot esculenta Crantz) were achieved using primed in situ labeling. Amplified signals for both the EST507-1 and SSRY13-5 markers were consistently observed in different stages of cell division. A comparison of the length, arm ratio, and other morphological characteristics of somatic metaphase chromosomes in karyotype analysis indicated that the EST507-1 and SSRY13-5 markers were localized on the short and long arm of cassava chromosome 11 with the relative map positions of 41.67 and 23.07, respectively. The physical localization of the 2 markers on chromosome 11 of the karyotype corresponds to their positions on the 15th linkage group in cassava. PMID:26345763

  4. 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

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

    2008-01-01

    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

  5. Comparative petiole anatomy of cassava (Manihot) species.

    PubMed

    Graciano-Ribeiro, D; Hashimoto-Freitas, D Y; Nassar, N M A

    2016-01-01

    In this study, we describe the petiole anatomy of six wild cassava (Manihot) species, one hybrid, and two cultivars of Manihot esculenta, in order to identify their dominant anatomical patterns and relate them to possible adaptations to abiotic factors in the Cerrado biome. The median parts of several petiole samples were transversally and longitudinally sectioned and stained. The results include data for the taxonomic classification of the genus, including distinctive anatomical characteristics of hybrid varieties of cassava and wild species, such as the presence/absence of trichomes and a hypodermis, layer type and number in the cortex, number of vascular bundles, cell types in the pith, and type of organization. Morphological analysis revealed differences in length and shape of the petiole insertion. The presence of trichomes, a hypodermis, the amount and type of supporting tissue in the cortex, as well as gelatinous fibers, may be related to drought tolerance. PMID:26909917

  6. 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...

  7. Wild Manihot Species Do Not Possess C4 Photosynthesis

    PubMed Central

    CALATAYUD, P.‐A.; BARÓN, C. H.; VELÁSQUEZ, H.; ARROYAVE, J. A.; LAMAZE, T.

    2002-01-01

    Cultivated cassava (Manihot esculenta) has a higher rate of photosynthesis than is usual for C3 plants and photosynthesis is not light saturated. For these reasons it has been suggested that cultivated cassava could be derived from wild species possessing C4 photosynthesis. The natural abundance of 13C and activities of phosphoenolpyruvate carboxylase and phosphoglycolate phosphatase were measured in leaves of 20 wild cassava species to test this hypothesis. All the species studied, including M. flabellifolia the potential wild progenitor of cultivated cassava, clearly exhibited C3 not C4 characteristics. PMID:12096814

  8. Thermodynamic analysis of sorption isotherms of cassava (Manihot esculenta).

    PubMed

    Koua, Blaise Kamenan; Koffi, Paul Magloire Ekoun; Gbaha, Prosper; Toure, Siaka

    2014-09-01

    Sorption isotherms of cassava were determined experimentally using a static gravimetric method at 30, 45 and 60 °C and within the range of 0.10-0.90 water activity. At a constant water activity, equilibrium moisture content decreased with increasing temperature. The equilibrium moisture content increased with increasing water activity at a given temperature. The experimental results were modelled using seven sorption models using non-linear regression technique. Results demonstrated that the GAB model adequately predicted equilibrium moisture content of cassava for the range of temperatures and water activities studied. The thermodynamic functions such as net isosteric heat of sorption, differential entropy of sorption, net integral enthalpy and entropy were evaluated to provide an understanding of the properties of water and energy requirements associated with the sorption behaviour. Net isosteric heat and differential entropy decreased with increasing equilibrium moisture content. The net integral enthalpy decreased while net integral entropy increased with increasing equilibrium moisture content. Net integral entropy was negative in value. All thermodynamic functions were adequately characterised by a power law model. The point of maximum stability was found between 0.053 and 0.154 kg water/kg db for cassava. PMID:25190827

  9. Nutritional composition of fufu analog flour produced from Cassava root (Manihot esculenta) and Cocoyam (Colocasia esculenta) tuber.

    PubMed

    Bamidele, Oluwaseun P; Fasogbon, Mofoluwaso B; Oladiran, Dolapo A; Akande, Ebunoluwa O

    2015-11-01

    Nutritional properties of fufu analog produced from co-processing of cassava and cocoyam were studied. Cassava and cocoyam were fermented for 72 h, dried to obtain fufu flour. Proximate, functional, minerals, antinutritional factor, pasting properties, and sensory evaluation of various samples were determined. The results revealed that the moisture contents of the samples showed significant difference from control with values between 6.50 and 7.30%. The protein contents (1.68-4.98%), ash (1.84-4.01%), and crude fiber (1.42-4.56%) showed significant increase with increasing level of cocoyam, while the crude fat and carbohydrate reduced with increase in cocoyam. The minerals also increased with increase in cocoyam level with sample E having the highest value of Magnesium (32.15 mg/100 g). The antinutritional factors were very low and the pasting properties revealed the importance of cocoyam in the fufu analog produced. In conclusion, fufu produced from co-processing of cassava and cocoyam has more nutritional qualities than the common fufu made from cassava alone. PMID:26788301

  10. Protein extraction and enzymatic hydrolysis of ammonia-treated cassava leaves (Manihot esculenta Crantz).

    PubMed

    Urribarrí, Lauris; Chacón, David; González, Orlaidy; Ferrer, Alexis

    2009-05-01

    In the present work, cassava leaves were treated with 0.5 kg ammonia/kg dry matter at 78 degrees C and 30% moisture content in a 2-kg reactor. Protein extraction was carried out with a calcium hydroxide solution (pH 10) for 30 min at several temperatures (30 degrees C, 45 degrees C, 60 degrees C, 75 degrees C, and 90 degrees C) and solid/liquid ratios (1:10 and 1:15) in a thermostatized bath. Soluble protein content of the extracts was determined by Lowry's method. Dry substrate concentrations of 5%, 7.5%, and 10% and enzyme doses of 2 and 5 IU/g dry matter were used for the enzymatic hydrolysis in an orbital incubator at 50 degrees C and 100 rpm. Both cellulase and xylanase were used. Reducing sugars produced were determined with the dinitrosalicylic acid method. The highest protein extraction yield for the ammonia-treated leaves was 29.10%, which was 50% higher than with the untreated leaves (20%), and was obtained at 90 degrees C with a 1:10 solid/liquid ratio. The concentrate had a protein content of 36.35% and the amino acid profile was suitable for swine and poultry. The highest sugar yield was 54.72% with respect to theoretical and was obtained with 5% solids and an enzyme dose of 5 IU/g dry matter. This yield was 3.4 times higher than the yield of the untreated leaves (16.13%). These results indicate that cassava leaves have a great potential for animal feeding and ethanol production. Both protein extraction and sugar yields may be enhanced by optimizing the ammonia treatment. PMID:19067247

  11. Comparison of Leaf Proteomes of Cassava (Manihot esculenta Crantz) Cultivar NZ199 Diploid and Autotetraploid Genotypes

    PubMed Central

    An, Feifei; Fan, Jie; Li, Jun; Li, Qing X.; Li, Kaimian; Zhu, Wenli; Wen, Feng; Carvalho, Luiz J. C. B.; Chen, Songbi

    2014-01-01

    Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN) metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies. PMID:24727655

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

    PubMed

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

    2012-05-01

    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

  13. Unraveling complex viral infections in cassava (Manihot esculenta Crantz) from Colombia.

    PubMed

    Carvajal-Yepes, Monica; Olaya, Cristian; Lozano, Ivan; Cuervo, Maritza; Castaño, Mauricio; Cuellar, Wilmer J

    2014-06-24

    In the Americas, different disease symptoms have been reported in cassava including leaf mosaics, vein clearings, mottles, ring spots, leaf distortions and undeveloped and deformed storage roots. Some viruses have been identified and associated with these symptoms while others have been reported in symptomless plants or latent infections. We observed that reoviruses associated with severe root symptoms (RS) of Cassava Frogskin Disease (CFSD) are not associated with leaf symptoms (LS) observed in the cassava indicator plant 'Secundina'. Neither were these LS associated with the previously characterized Cassava common mosaic virus, Cassava virus X, Cassava vein mosaic virus or phytoplasma, suggesting the presence of additional pathogens. In order to explain LS observed in cassava we used a combination of biological, serological and molecular tests. Here, we report three newly described viruses belonging to the families Secoviridae, Alphaflexiviridae and Luteoviridae found in cassava plants showing severe RS associated with CFSD. All tested plants were infected by a mix of viruses that induced distinct LS in 'Secundina'. Out of the three newly described viruses, a member of family Secoviridae could experimentally induce LS in single infection. Our results confirm the common occurrence of complex viral infections in cassava field-collected since the 1980s. PMID:24374265

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

    TOXLINE Toxicology Bibliographic Information

    Nuwamanya E; Chiwona-Karltun L; Kawuki RS; Baguma Y

    2012-05-01

    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.

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

    PubMed Central

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

    2010-01-01

    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. PMID:21062208

  16. Traditional anthropology and geographical information systems in the collaborative study of Cassava in Africa

    NASA Technical Reports Server (NTRS)

    Romanoff, Steven

    1991-01-01

    Cross-cultural, village-level, and farmer surveys have been used with a geographical information system to describe the distribution and relative importance of cassava (manioc, yuca, Manihot esculenta) in its cultural, economic, and ecological contexts. It presents examples of data management for mapping, sample selection, cross-tabulation of characteristics, combination of data types for indices and hypothesis testing. The methods used are reviewed, and some of the main conclusions of the study are presented.

  17. Comparative analysis of virus-derived small RNAs within cassava (Manihot esculenta Crantz) infected with cassava brown streak viruses.

    PubMed

    Ogwok, Emmanuel; Ilyas, Muhammad; Alicai, Titus; Rey, Marie E C; Taylor, Nigel J

    2016-04-01

    Infection of plant cells by viral pathogens triggers RNA silencing, an innate antiviral defense mechanism. In response to infection, small RNAs (sRNAs) are produced that associate with Argonaute (AGO)-containing silencing complexes which act to inactivate viral genomes by posttranscriptional gene silencing (PTGS). Deep sequencing was used to compare virus-derived small RNAs (vsRNAs) in cassava genotypes NASE 3, TME 204 and 60444 infected with the positive sense single-stranded RNA (+ssRNA) viruses cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), the causal agents of cassava brown streak disease (CBSD). An abundance of 21-24nt vsRNAs was detected and mapped, covering the entire CBSV and UCBSV genomes. The 21nt vsRNAs were most predominant, followed by the 22 nt class with a slight bias toward sense compared to antisense polarity, and a bias for adenine and uracil bases present at the 5'-terminus. Distribution and frequency of vsRNAs differed between cassava genotypes and viral genomes. In susceptible genotypes TME 204 and 60444, CBSV-derived sRNAs were seen in greater abundance than UCBSV-derived sRNAs. NASE 3, known to be resistant to UCBSV, accumulated negligible UCBSV-derived sRNAs but high populations of CBSV-derived sRNAs. Transcript levels of cassava homologues of AGO2, DCL2 and DCL4, which are central to the gene-silencing complex, were found to be differentially regulated in CBSV- and UCBSV-infected plants across genotypes, suggesting these proteins play a role in antiviral defense. Irrespective of genotype or viral pathogen, maximum populations of vsRNAs mapped to the cytoplasmic inclusion, P1 and P3 protein-encoding regions. Our results indicate disparity between CBSV and UCBSV host-virus interaction mechanisms, and provide insight into the role of virus-induced gene silencing as a mechanism of resistance to CBSD. PMID:26811902

  18. Factors influencing somatic embryogenesis, regeneration, and Agrobacterium-mediated transformation of cassava (Manihot esculenta Crantz) cultivar TME14

    PubMed Central

    Nyaboga, Evans N.; Njiru, Joshua M.; Tripathi, Leena

    2015-01-01

    Routine production of large numbers of transgenic plants is required to fully exploit advances in cassava biotechnology and support development of improved germplasm for deployment to farmers. This article describes an improved, high-efficiency transformation protocol for recalcitrant cassava cultivar TME14 preferred in Africa. Factors that favor production of friable embryogenic calli (FEC) were found to be use of DKW medium, crushing of organized embryogenic structures (OES) through 1–2 mm sized metal wire mesh, washing of crushed OES tissues and short exposure of tyrosine to somatic embryos; and transformation efficiency was enhanced by use of low Agrobacterium density during co-cultivation, co-centrifugation of FEC with Agrobacterium, germination of paramomycin resistant somatic embryos on medium containing BAP with gradual increase in concentration and variations of the frequency of subculture of cotyledonary-stage embryos on shoot elongation medium. By applying the optimized parameters, FEC were produced for cassava cultivar TME14 and transformed using Agrobacterium strain LBA4404 harboring the binary vector pCAMBIA2301. About 70–80 independent transgenic lines per ml settled cell volume (SCV) of FEC were regenerated on selective medium. Histochemical GUS assays confirmed the expression of gusA gene in transformed calli, somatic embryos and transgenic plants. The presence and integration of the gusA gene were confirmed by PCR and Southern blot analysis, respectively. RT-PCR analysis of transgenic plants confirmed the expression of gusA gene. This protocol demonstrates significantly enhanced transformation efficiency over existing cassava transformation protocols and could become a powerful tool for functional genomics and transferring new traits into cassava. PMID:26113851

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

    PubMed

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

    2012-12-01

    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

  20. Comparative analysis of virus-derived small RNAs within cassava (Manihot esculenta Crantz) infected with cassava brown streak viruses

    PubMed Central

    Ogwok, Emmanuel; Ilyas, Muhammad; Alicai, Titus; Rey, Marie E.C.; Taylor, Nigel J.

    2016-01-01

    Infection of plant cells by viral pathogens triggers RNA silencing, an innate antiviral defense mechanism. In response to infection, small RNAs (sRNAs) are produced that associate with Argonaute (AGO)-containing silencing complexes which act to inactivate viral genomes by posttranscriptional gene silencing (PTGS). Deep sequencing was used to compare virus-derived small RNAs (vsRNAs) in cassava genotypes NASE 3, TME 204 and 60444 infected with the positive sense single-stranded RNA (+ssRNA) viruses cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), the causal agents of cassava brown streak disease (CBSD). An abundance of 21–24 nt vsRNAs was detected and mapped, covering the entire CBSV and UCBSV genomes. The 21 nt vsRNAs were most predominant, followed by the 22 nt class with a slight bias toward sense compared to antisense polarity, and a bias for adenine and uracil bases present at the 5′-terminus. Distribution and frequency of vsRNAs differed between cassava genotypes and viral genomes. In susceptible genotypes TME 204 and 60444, CBSV-derived sRNAs were seen in greater abundance than UCBSV-derived sRNAs. NASE 3, known to be resistant to UCBSV, accumulated negligible UCBSV-derived sRNAs but high populations of CBSV-derived sRNAs. Transcript levels of cassava homologues of AGO2, DCL2 and DCL4, which are central to the gene-silencing complex, were found to be differentially regulated in CBSV- and UCBSV-infected plants across genotypes, suggesting these proteins play a role in antiviral defense. Irrespective of genotype or viral pathogen, maximum populations of vsRNAs mapped to the cytoplasmic inclusion, P1 and P3 protein-encoding regions. Our results indicate disparity between CBSV and UCBSV host-virus interaction mechanisms, and provide insight into the role of virus-induced gene silencing as a mechanism of resistance to CBSD. PMID:26811902

  1. Cassava about-FACE: Greater than expected yield stimulation of cassava (Manihot esculenta) by future CO2 levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential for tuber crops such as cassava, yams and potatoes to enhance food security in the future is underestimated. In tuber crops there is the potential for a much higher ratio of edible to non-edible components than in above ground grain and bean crops such as rice, wheat, maize or soybean....

  2. Effects of processing, cooking, and storage on ß-carotene retention and bioaccessibility in biofortified cassava (Manihot esculenta)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofortification of cassava with beta-carotene is currently being tested in African populations where cassava is a staple food and vitamin A deficiency is a public health problem. Measuring the impact of traditional African processing and cooking on beta-carotene concentration and bioaccessibility ...

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

    SciTech Connect

    Sung, Shijean S.; Xu, Dianpeng; Black C.C. )

    1989-04-01

    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.

  4. Effect of elevated CO2 concentration and nitrate: ammonium ratios on gas exchange and growth of cassava (Manihot esculenta Crantz)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluated how different nitrogen forms affect growth and photosynthetic responses of cassava to CO2 concentration. Cassava was grown in 12-L pots in a greenhouse (30/25o C day / night) at 390 or 750 ppm of CO2. Three nitrogen treatments were applied: (a) 12 mM NO3-, (b) 6 mM NO3- + 6 mM N...

  5. Phylogeny and expression pattern of starch branching enzyme family genes in cassava (Manihot esculenta Crantz) under diverse environments.

    PubMed

    Pei, Jinli; Wang, Huijun; Xia, Zhiqiang; Liu, Chen; Chen, Xin; Ma, Pingan; Lu, Cheng; Wang, Wenquan

    2015-08-01

    Starch branching enzyme (SBE) is one of the key enzymes involved in starch biosynthetic metabolism. In this study, six SBE family genes were identified from the cassava genome. Phylogenetic analysis divided the MeSBE family genes into dicot family A, B, C, and the new group. Tissue-specific analysis showed that MeSBE2.2 was strongly expressed in leaves, stems cortex, and root stele, and MeSBE3 had high expression levels in stem cortex and root stele of plants in the rapid growth stage under field condition, whereas the expression levels of MeSBE2.1, MeSBE4, and MeSBE5 were low except for in stems cortex. The transcriptional activity of MeSBE2.2 and MeSBE3 was higher compared with other members and gradually increased in the storage roots during root growth process, while the other MeSBE members normally remained low expression levels. Expression of MeSBE2.2 could be induced by salt, drought, exogenous abscisic acid, jasmonic acid, and salicylic acid signals, while MeSBE3 had positive response to drought, salt, exogenous abscisic acid, and salicylic acid in leaves but not in storage root, indicating that they might be more important in starch biosynthesis pathway under diverse environments. PMID:25981533

  6. The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration.

    PubMed

    Uarrota, Virgílio Gavicho; Moresco, Rodolfo; Schmidt, Eder Carlos; Bouzon, Zenilda Laurita; Nunes, Eduardo da Costa; Neubert, Enilto de Oliveira; Peruch, Luiz Augusto Martins; Rocha, Miguel; Maraschin, Marcelo

    2016-04-15

    This study aimed to investigate the role of ascorbate peroxidase (APX), guaiacol peroxidase (GPX), polysaccharides, and protein contents associated with the early events of postharvest physiological deterioration (PPD) in cassava roots. Increases in APX and GPX activity, as well as total protein contents occurred from 3 to 5 days of storage and were correlated with the delay of PPD. Cassava samples stained with Periodic Acid-Schiff (PAS) highlighted the presence of starch and cellulose. Degradation of starch granules during PPD was also detected. Slight metachromatic reaction with toluidine blue is indicative of increasing of acidic polysaccharides and may play an important role in PPD delay. Principal component analysis (PCA) classified samples according to their levels of enzymatic activity based on the decision tree model which showed GPX and total protein amounts to be correlated with PPD. The Oriental (ORI) cultivar was more susceptible to PPD. PMID:26617011

  7. Cloning, 3D modeling and expression analysis of three vacuolar invertase genes from cassava (Manihot Esculenta Crantz).

    PubMed

    Yao, Yuan; Wu, Xiao-Hui; Geng, Meng-Ting; Li, Rui-Mei; Liu, Jiao; Hu, Xin-Wen; Guo, Jian-Chun

    2014-01-01

    Vacuolar invertase is one of the key enzymes in sucrose metabolism that irreversibly catalyzes the hydrolysis of sucrose to glucose and fructose in plants. In this research, three vacuolar invertase genes, named MeVINV1-3, and with 653, 660 and 639 amino acids, respectively, were cloned from cassava. The motifs of NDPNG (β-fructosidase motif), RDP and WECVD, which are conserved and essential for catalytic activity in the vacuolar invertase family, were found in MeVINV1 and MeVINV2. Meanwhile, in MeVINV3, instead of NDPNG we found the motif NGPDG, in which the three amino acids GPD are different from those in other vacuolar invertases (DPN) that might result in MeVINV3 being an inactivated protein. The N-terminal leader sequence of MeVINVs contains a signal anchor, which is associated with the sorting of vacuolar invertase to vacuole. The overall predicted 3D structure of the MeVINVs consists of a five bladed β-propeller module at N-terminus domain, and forms a β-sandwich module at the C-terminus domain. The active site of the protein is situated in the β-propeller module. MeVINVs are classified in two subfamilies, α and β groups, in which α group members of MeVINV1 and 2 are highly expressed in reproductive organs and tuber roots (considered as sink organs), while β group members of MeVINV3 are highly expressed in leaves (source organs). All MeVINVs are highly expressed in leaves, while only MeVINV1 and 2 are highly expressed in tubers at cassava tuber maturity stage. Thus, MeVINV1 and 2 play an important role in sucrose unloading and starch accumulation, as well in buffering the pools of sucrose, hexoses and sugar phosphates in leaves, specifically at later stages of plant development. PMID:24838076

  8. Effect of feeding cassava (Manihot esculenta Crantz) root meal on growth performance, hydrocyanide intake and haematological parameters of broiler chicks.

    PubMed

    Akapo, Abiola Olajetemi; Oso, Abimbola Oladele; Bamgbose, Adeyemi Mustapha; Sanwo, Kehinde A; Jegede, Adebayo Vincent; Sobayo, Richard Abayomi; Idowu, Olusegun Mark; Fan, Juexin; Li, Lili; Olorunsola, Rotimi A

    2014-10-01

    The effect of feeding cassava root meal on growth performance, hydrocyanide intake, haematological indices and serum thiocyanate concentration of broiler chicks was investigated using 300-day-old male broilers. There were five dietary treatments arranged in a 2 × 2 + 1 factorial arrangement of two processing methods of cassava root (peeled and unpeeled) included at two levels (100 and 200 g/kg) plus a control diet (maize-based diet, containing no cassava root). Each treatment was replicated six times with ten birds per replicate. The feeding trial lasted for 28 days. Control-fed birds had the highest overall (P < 0.01) final liveweight and weight gain, least (P < 0.05) hydrocyanide (HCN) intake and best (P < 0.05) feed-to-gain ratio. Chicks fed with control and diet containing 100 g/kg peeled cassava root meal (PCRM) had the least (P < 0.05) feed cost per weight gain. Chicks fed with diet containing 100 g/kg cassava root meal had higher (P < 0.05) final liveweight and weight gain and reduced (P < 0.05) HCN intake than chicks fed with diet containing 200 g/kg cassava root meal. Dietary inclusion of peeled cassava root meal (PCRM) for broiler chicks resulted in increased final liveweight (P < 0.05), weight gain (P < 0.01) and feed intake (P < 0.01) when compared with birds fed with diet containing unpeeled cassava root meal (UCRM). The least (P < 0.01) final liveweight and weight gain and worst (P < 0.05) feed-to-gain ratio were obtained with chicks fed with diet containing 200 g/kg UCRM. Increased dietary inclusion levels of cassava root resulted in significant increase (P < 0.05) in white blood cell (WBC) count, heterophil count and serum thiocyanate concentration. In comparison with chicks fed with diet containing UCRM, dietary inclusion of PCRM resulted in increased (P < 0.05) red blood cell (RBC) count and haemoglobin (Hb) concentration and reduced (P < 0.05) white blood cell (WBC) count and serum thiocyanate concentration. Although inclusion of 100 g/kg PCRM showed some economic sense, dietary inclusion of either peeled or unpeeled cassava root poses a threat on growth and health status of broiler chicks. PMID:24913764

  9. The Metabolic Effects of Consumption of Yellow Cassava (Manihot esculenta Crantz) on Some Biochemical Parameters in Experimental Rats.

    PubMed

    Udeme, Nelson; Okafor, Polycarp; Eleazu, Chinedum

    2015-01-01

    The metabolism of yellow cassava (variety TMS 01/1368) was investigated in male albino rats fed a diet containing yellow cassava for 7 to 28 days. There were significant increases (P < 0.05) in total and free cyanide and thiocyanate in the sera and urine samples of the experimental rats compared with the control, significant increases (P < 0.05) in serum glucose, alanine aminotransaminase, aspartate aminotransaminase, and alkaline phosphatase levels of the experimental rats compared with the control, significant decreases (P < 0.05) in serum albumin of the experimental rats compared with the control, but no significant differences (P > 0.05) in the serum total proteins of the experimental rats compared with the control. The experimental rats treated for 7, 14, 21, or 28 days exhibited body weight decreases of 5.11%, 11.10%, 19.16%, and 24.18%, respectively, whereas the control group showed 9.17% gain in body weight. Total and free cyanide concentrations were detected in the liver, kidney, and heart of most of the rats in both the experimental and control groups, except for free cyanide in the control group that was not detected. Metabolism of the yellow cassava variety in experimental rats was capable of exposing the animals to cyanide, underscoring the need for its proper processing before consumption by humans. PMID:26467190

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

    PubMed

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

    2014-06-01

    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

  11. Factors influencing somatic embryogenesis, regeneration, and Agrobacterium-mediated transformation of cassava (Manihot esculenta Crantz) cultivar TME14.

    PubMed

    Nyaboga, Evans N; Njiru, Joshua M; Tripathi, Leena

    2015-01-01

    Routine production of large numbers of transgenic plants is required to fully exploit advances in cassava biotechnology and support development of improved germplasm for deployment to farmers. This article describes an improved, high-efficiency transformation protocol for recalcitrant cassava cultivar TME14 preferred in Africa. Factors that favor production of friable embryogenic calli (FEC) were found to be use of DKW medium, crushing of organized embryogenic structures (OES) through 1-2 mm sized metal wire mesh, washing of crushed OES tissues and short exposure of tyrosine to somatic embryos; and transformation efficiency was enhanced by use of low Agrobacterium density during co-cultivation, co-centrifugation of FEC with Agrobacterium, germination of paramomycin resistant somatic embryos on medium containing BAP with gradual increase in concentration and variations of the frequency of subculture of cotyledonary-stage embryos on shoot elongation medium. By applying the optimized parameters, FEC were produced for cassava cultivar TME14 and transformed using Agrobacterium strain LBA4404 harboring the binary vector pCAMBIA2301. About 70-80 independent transgenic lines per ml settled cell volume (SCV) of FEC were regenerated on selective medium. Histochemical GUS assays confirmed the expression of gusA gene in transformed calli, somatic embryos and transgenic plants. The presence and integration of the gusA gene were confirmed by PCR and Southern blot analysis, respectively. RT-PCR analysis of transgenic plants confirmed the expression of gusA gene. This protocol demonstrates significantly enhanced transformation efficiency over existing cassava transformation protocols and could become a powerful tool for functional genomics and transferring new traits into cassava. PMID:26113851

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

    PubMed Central

    Carvalho, Lucia M. J.; Oliveira, Alcides R. G.; Godoy, Ronoel L. O.; Pacheco, Sidney; Nutti, Marília R.; de Carvalho, José L. V.; Pereira, Elenilda J.; Fukuda, Wânia G.

    2012-01-01

    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, β-carotene, and its all-E-, 9-, and 13-Z-β-carotene isomers content in seven yellow sweet cassava roots and their retention after three boiling cooking methods. Design The total carotenoid, β-carotene, and its all-E-, 9-, and 13-Z-β-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 β-carotene from 1.99 to 10.32 µg/g. The β-carotene predominated in all the roots. The Híbrido 2003 14 08 cultivar presented the highest β-carotene content after cooking methods 1 and 3. The 1153 – Klainasik cultivar presented the highest 9-Z-β-carotene content after cooking by method 3. The highest total carotenoid retention was observed in cultivar 1456 – Vermelhinha and that of β-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 β-carotene retention in all the cultivars. Conclusion Differences were found in the cooking methods among the samples regarding total carotenoid or β-carotene retention, suggesting that the different behaviors of the cultivars need to be further analyzed. However, high percentages of total carotenoid or β-carotene retention were observed and can minimize vitamin A deficiency in low-income populations. PMID:22468142

  13. An efficient genetic manipulation protocol for Ustilago esculenta.

    PubMed

    Yu, Jiajia; Zhang, Yafen; Cui, Haifeng; Hu, Peng; Yu, Xiaoping; Ye, Zihong

    2015-06-01

    Ustilago esculenta grows within the flowering stem of the aquatic grass Zizania latifolia, resembling a fungal endophyte. The fungus colonizes Z. latifolia and induces swelling which results in the formation of galls near the base of the plant. Due to their unique flavor and textures these galls are considered as a delicacy in southern China. Efficient genetic manipulation is required to determine the relationship between U. esculenta and Z. latifolia. In this study, we report a protoplast-based transformation system for this unique fungal species. We have explored various factors (enzyme digesting conditions, osmotic pressure stabilizers, vectors and selection agents) that might impact protoplast yield and high frequencies of transformation. A haploid strain (UeT55) of U. esculenta was found to produce higher yields of protoplasts when treating with 15 mg mL(-1) lywallzyme in a sucrose-containing solution at 30°C for 3 h. The transformation frequencies were higher when fungal strain was transformed with a linear plasmid harboring hygromycin or carboxin resistance gene and regenerated on a sucrose-containing medium. A UeICL gene (coding isocitrate lyase) was disrupted and an EGFP (coding enhanced green fluorescent protein) gene was overexpressed successfully in the UeT55 strain using the developed conditions. The genetic manipulation system reported in this study will open up new opportunities for forward and reverse genetics in U. esculenta. PMID:26038251

  14. Antimetastatic activity isolated from Colocasia esculenta (Taro)

    PubMed Central

    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

    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. PMID:21934603

  15. Treatment of chronic kidney disease using a traditional Chinese medicine, Flos Abelmoschus manihot (Linnaeus) Medicus (Malvaceae).

    PubMed

    Chen, Yizhi; Cai, Guangyan; Sun, Xuefeng; Chen, Xiangmei

    2016-02-01

    The flowers of Abelmoschus manihot (Linnaeus) Medicus (Malvaceae; Flos A. manihot) have been used in China for many centuries as a traditional Chinese medicine for the treatment of chronic kidney disease. The Huangkui capsule is a single-plant drug extracted from the dry corolla of Flos A. manihot that has been approved by China's State Food and Drug Administration for the treatment of chronic glomerulonephritis. The purpose of this paper is to review briefly some of the past experiences in rapid filtration and to present more fully a few facts brought out in recent studies. The primary chemical constituents of Flos A. manihot are flavonoids. In vivo, the flavonoids can be transformed into glucuronide-sulphate conjugates, which are the major metabolites of Flos A. manihot and could contribute to the renoprotective effects in vivo. Flos A. manihot can ameliorate proteinuria, podocyte apoptosis, glomerulosclerosis and mesangial proliferation. The renoprotective effects of Flos A. manihot are related to inhibition of caspase-3 and caspase-8 overexpression, reduction of the infiltration of ED1(+) and ED3(+) macrophages, downregulation of oxidative stress, inhibition of the p38 mitogen-activated protein kinase and serine/threonine kinase pathways and suppression of transforming growth factor-β1 and tumour necrosis factor-α expression. Recently, a multicentre randomized controlled trial demonstrated that Flos A. manihot was more effective than the angiotensin-receptor blocker losartan in reducing proteinuria in patients with primary glomerular disease. Because Flos A. manihot is generally preferred by Chinese patients and clinicians, high-quality trials to test the efficacy and safety of Flos A. manihot are urgently needed. PMID:26667396

  16. Fermentation optimization and antioxidant activities of mycelial polysaccharides from Morchella esculenta using soybean residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mycelial polysaccharides from Morchella esculenta are active ingredients in a number of medicines that play important roles in immunity improvement and tumor growth inhibition. So far, the production of polysaccharides from M. esculenta mycelia has not been commercialized. The aims of this wor...

  17. Isozymes analysis of the golden cuttlefish Sepia esculenta (Cephalopoda: Sepiidae)

    NASA Astrophysics Data System (ADS)

    Zheng, Xiaodong; Zhao, Jianmin; Xiao, Shu; Wang, Rucai; Wang, Shidang; Zhou, Weiwu

    2004-04-01

    Thirty-nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH, MDH, MEP, IDHP, PGDH, GRS, NP, AAT, CK, AK, EST, ALP, ACP, FBP, MPI, GPI and PGM) show strong activities and good convergence in zymogram. They are proved to be suitable genetic markers in Sepia esculenta. Among the tissues used, mantle muscle is the best for electrophoretic analysis of isozymes. Eye and liver are fairly good for some special enzymes, such as LDH, EST, MPI, etc. Twenty-six loci are detected. The proportion of polymorphic loci is 0.115 in the Qingdao sample and 0.153 in the Rizhao sample (P<0.99). The mean values of the observed and expected heterozygosity per locus of Qingdao sample are 0.016 and 0.017, while those of the Rizhao sample are 0.023 and 0.025 respectively.

  18. Characterization of Carotenoid-protein Complexes and Gene Expression Analysis Associated with Carotenoid Sequestration in Pigmented Cassava (Manihot Esculenta Crantz) Storage Root

    PubMed Central

    Carvalho, Luiz Joaquim Castelo Branco; Lippolis, John; Chen, Songbi; Batista de Souza, Claudia Regina; Vieira, Eduardo A; Anderson, James V

    2012-01-01

    Carotenoid-protein complex (CPC) was isolated from chromoplast-enriched suspensions of cassava storage root (CSR) using size exclusion chromatography and characterized. Peptide sequences (LC_MS/MS spectrum) obtained from CPC and their corresponding proteins were obtained using publically available databases. Small Heat Shock Proteins (sHSPs) were the most abundant proteins identified in the CPC. Western blot analysis showed that Fribrillin and Or-protein were present in chromoplast-enriched suspensions of yellow root but not in the complex or white root. Results from qRT-PCR helped identify an isoform of HSP21 possessing four single point mutations in the intense yellow CSR that may be responsible for increased sequestration of b-carotene. PMID:23230451

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

    PubMed

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

    2013-08-01

    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

  20. 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...

  1. Synthesis of an air-working trilayer artificial muscle using a conductive cassava starch biofilm (manihot esculenta, cranz) and polypyrrole (PPy)

    NASA Astrophysics Data System (ADS)

    Núñez D, Y. E.; Arrieta A, Á. A.; Segura B, J. A.; Bertel H, S. D.

    2016-02-01

    In this study, a methodology for obtaining a conductive cassava starch biofilm doped with lithium perchlorate (LiClO4) is shown, as well as the electrochemical technique for the synthesis of polypyrrole films, which are used for developing the trilayer artificial muscle PPy/Biopolymer/PPy designed to operate in air. Furthermore, results from the trilayer movement using chronoamperometric techniques are shown.

  2. Diversity, Physicochemical and Technological Characterization of Elite Cassava (Manihot esculenta Crantz) Cultivars of Bantè, a District of Central Benin

    PubMed Central

    Sanoussi, Abadjayé Faouziath; Loko, Laura Yéyinou; Ahissou, Hyacinthe; Adjahi, Adidjath Koubourath; Orobiyi, Azize; Agré, Angelot Paterne; Azokpota, Paulin; Dansi, Alexandre; Sanni, Ambaliou

    2015-01-01

    Cassava is one of the staple food crops contributing significantly to food and nutrition security in Benin. This study aimed to assess the diversity of the elite cassava cultivars of Bantè district, determine the physicochemical properties of the most preferred ones as well as the sensory attributes of their major derived products (gari and tapioca), and compare them with the farmers' and processors' perception on their technological qualities. The ethnobotanical investigation revealed existence of 40 cultivars including 9 elites that were further classified into three groups based on agronomics and technological and culinary properties. Clustered together, cultivars Idilèrou, Monlèkangan, and Odohoungbo characterized by low fiber content, high yield of gari and tapioca, and good in-ground postmaturity storage were the most preferred ones. Their physicochemical analysis revealed good rate of dry matters (39.8% to 41.13%), starch (24.47% to 25.5%) and total sugars (39.46% to 41.13%), low fiber (0.80% to 1.02%), and cyanide (50 mg/kg) contents. The sensory analysis of their gari and tapioca revealed very well appreciated (taste, color, and texture) products by the consumers. The confirmation by scientific analysis of the farmers' perception on qualities of the most preferred cultivars indicated that they have good knowledge of their materials. PMID:26693522

  3. Quantification of African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV-UG) in single and mixed infected Cassava (Manihot esculenta Crantz) using quantitative PCR.

    PubMed

    Naseem, Saadia; Winter, Stephan

    2016-01-01

    The quantity of genomic DNA-A and DNA-B of African cassava mosaic virus (ACMV) and East African cassava mosaic virus Uganda (Uganda variant, EACMV-UG) was analysed using quantitative PCR to assess virus concentrations in plants from susceptible and tolerant cultivars. The concentrations of genome components in absolute and relative quantification experiments in single and mixed viral infections were determined. Virus concentration was much higher in symptomatic leaf tissues compared to non-symptomatic leaves and corresponded with the severity of disease symptoms. In general, higher titres were recorded for EACMV-UG Ca055 compared to ACMV DRC6. The quantitative assessment also showed that the distribution of both viruses in the moderately resistant cassava cv. TMS 30572 was not different from the highly susceptible cv. TME 117. Natural mixed infections with both viruses gave severe disease symptoms. Relative quantification of virus genomes in mixed infections showed higher concentrations of EACMV-UG DNA-A compared to ACMV DNA-A, but a marked reduction of EACMV-UG DNA-B. The higher concentrations of EACMV-UG DNA-B compared to EACMV DNA-A accumulation in single infections were consistent. Since DNA-B is implicated in virus cell-to-cell spread and systemic movement, the abundance of the EACMV-UG DNA-B may be an important factor driving cassava mosaic disease epidemic. PMID:26456453

  4. Impact of genotype and cooking style on the content, retention, and bioacessibility of β-carotene in biofortified cassava (Manihot esculenta Crantz) conventionally bred in Brazil.

    PubMed

    Berni, Paulo; Chitchumroonchokchai, Chureeporn; Canniatti-Brazaca, Solange G; De Moura, Fabiana F; Failla, Mark L

    2014-07-16

    Biofortification is a strategy for decreasing micronutrient deficiencies in vulnerable populations by increasing nutrient density in staple food crops. Roots from five varieties of cassava biofortified with β-carotene (βC), three parental accessions, and one variety of commonly consumed white cassava from Brazil were investigated. Roots from biofortified varieties contained up to 23-fold higher βC than white cassava, and the additional complement of βC was primarily the all-trans isomer. At least 68% of βC per gram fresh weight was retained after boiling or boiling and briefly frying. Micellarization of βC during simulated digestion of fried root exceeded that of boiled root. Apical uptake of all-trans-βC from mixed micelles by Caco-2 cells was affected by an interaction between variety and cooking style. These results suggest that Brazilian cassava biofortified with βC has the potential to reduce vitamin A deficiency without requiring major changes in local and ethnic styles of home cooking. PMID:24970565

  5. Characterization of carotenoid-protein complexes and gene expression analysis associated with carotenoid sequestration in pigmented cassava (Manihot esculenta Crantz) storage root

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carotenoid-protein complex separation by size exclusion chromatography, protein fractionation by SDS-PAGE, and shotgun PROTEOMICS technology were used to identify and characterize carotenoid associated proteins (CAPs) of chromoplast-enriched suspensions from cassava intense yellow storage root. A no...

  6. Diversity, Physicochemical and Technological Characterization of Elite Cassava (Manihot esculenta Crantz) Cultivars of Bantè, a District of Central Benin.

    PubMed

    Sanoussi, Abadjayé Faouziath; Loko, Laura Yéyinou; Ahissou, Hyacinthe; Adjahi, Adidjath Koubourath; Orobiyi, Azize; Agré, Angelot Paterne; Azokpota, Paulin; Dansi, Alexandre; Sanni, Ambaliou

    2015-01-01

    Cassava is one of the staple food crops contributing significantly to food and nutrition security in Benin. This study aimed to assess the diversity of the elite cassava cultivars of Bantè district, determine the physicochemical properties of the most preferred ones as well as the sensory attributes of their major derived products (gari and tapioca), and compare them with the farmers' and processors' perception on their technological qualities. The ethnobotanical investigation revealed existence of 40 cultivars including 9 elites that were further classified into three groups based on agronomics and technological and culinary properties. Clustered together, cultivars Idilèrou, Monlèkangan, and Odohoungbo characterized by low fiber content, high yield of gari and tapioca, and good in-ground postmaturity storage were the most preferred ones. Their physicochemical analysis revealed good rate of dry matters (39.8% to 41.13%), starch (24.47% to 25.5%) and total sugars (39.46% to 41.13%), low fiber (0.80% to 1.02%), and cyanide (50 mg/kg) contents. The sensory analysis of their gari and tapioca revealed very well appreciated (taste, color, and texture) products by the consumers. The confirmation by scientific analysis of the farmers' perception on qualities of the most preferred cultivars indicated that they have good knowledge of their materials. PMID:26693522

  7. Genome-wide identification, 3D modeling, expression and enzymatic activity analysis of cell wall invertase gene family from cassava (Manihot esculenta Crantz).

    PubMed

    Yao, Yuan; Geng, Meng-Ting; Wu, Xiao-Hui; Liu, Jiao; Li, Rui-Mei; Hu, Xin-Wen; Guo, Jian-Chun

    2014-01-01

    The cell wall invertases play a crucial role on the sucrose metabolism in plant source and sink organs. In this research, six cell wall invertase genes (MeCWINV1-6) were cloned from cassava. All the MeCWINVs contain a putative signal peptide with a predicted extracellular location. The overall predicted structures of the MeCWINV1-6 are similar to AtcwINV1. Their N-terminus domain forms a β-propeller module and three conserved sequence domains (NDPNG, RDP and WECP(V)D), in which the catalytic residues are situated in these domains; while the C-terminus domain consists of a β-sandwich module. The predicted structure of Pro residue from the WECPD (MeCWINV1, 2, 5, and 6), and Val residue from the WECVD (MeCWINV3 and 4) are different. The activity of MeCWINV1 and 3 were higher than other MeCWINVs in leaves and tubers, which suggested that sucrose was mainly catalyzed by the MeCWINV1 and 3 in the apoplastic space of cassava source and sink organs. The transcriptional levels of all the MeCWINVs and their enzymatic activity were lower in tubers than in leaves at all the stages during the cassava tuber development. It suggested that the major role of the MeCWINVs was on the regulation of carbon exportation from source leaves, and the ratio of sucrose to hexose in the apoplasts; the role of these enzymes on the sucrose unloading to tuber was weaker. PMID:24786092

  8. Metabolomics combined with chemometric tools (PCA, HCA, PLS-DA and SVM) for screening cassava (Manihot esculenta Crantz) roots during postharvest physiological deterioration.

    PubMed

    Uarrota, Virgílio Gavicho; Moresco, Rodolfo; Coelho, Bianca; Nunes, Eduardo da Costa; Peruch, Luiz Augusto Martins; Neubert, Enilto de Oliveira; Rocha, Miguel; Maraschin, Marcelo

    2014-10-15

    Cassava roots are an important source of dietary and industrial carbohydrates and suffer markedly from postharvest physiological deterioration (PPD). This paper deals with metabolomics combined with chemometric tools for screening the chemical and enzymatic composition in several genotypes of cassava roots during PPD. Metabolome analyses showed increases in carotenoids, flavonoids, anthocyanins, phenolics, reactive scavenging species, and enzymes (superoxide dismutase family, hydrogen peroxide, and catalase) until 3-5days postharvest. PPD correlated negatively with phenolics and carotenoids and positively with anthocyanins and flavonoids. Chemometric tools such as principal component analysis, partial least squares discriminant analysis, and support vector machines discriminated well cassava samples and enabled a good prediction of samples. Hierarchical clustering analyses grouped samples according to their levels of PPD and chemical compositions. PMID:24837923

  9. Identification and characterization of a cytotoxic polysaccharide from the flower of Abelmoschus manihot.

    PubMed

    Zheng, Xiao; Liu, Zhihui; Li, Shuang; Wang, Liling; Lv, Jiajia; Li, Junsheng; Ma, Xingmiao; Fan, Ling; Qian, Fang

    2016-01-01

    A low molecular weight polysaccharide was identified from the flower of Abelmoschus manihot (Linn.) Medicus, a popular herbal medicine also known as Flos A. manihot. The polysaccharide, AMPS-a, was obtained from the ethanol-extracted debris of Flos A. manihot by successive purification through DEAE-cellulose-52 and Sephadex G-100 column. AMPS-a has an estimated molecular weight of 8.8×10(3)Da and is mainly composed of β-d-glucose, α-d-mannose, α-d-galactose and α-l-fucose at a molar ratio of 1.00:0.91:2.14:1.09. The preliminary structural features were studied by hydrolysis-methylation analysis, GC-MS, FT-IR and (1)H and (13)C NMR spectroscopy. AMPS-a contains a backbone composed of repeating units of →6)α-d-Galp-(1→6)α-d-Manp-(1→6)α-d-Galp-(1→ with β-d-Glcp (1→3)α-Fucp-(1→ branching at O-3 of mannose. AMPS-a exhibited potent inhibitory effects on the proliferation of hepatic (SMMC-7721, HepG2) and gastric (MGC-803, MKN-45) cancer cells in vitro, and the sugar branches were indispensible for the cytotoxicity. Our work contributes to the first report of a novel cytotoxic polysaccharide from Flos A. manihot that may provide a potential source of anti-tumor agent. PMID:26478094

  10. Dendritic Cell Activation by Glucan Isolated from Umbilicaria Esculenta

    PubMed Central

    Kim, Hyung Sook; Kim, Jee Youn; Lee, Hong Kyung; Kim, Moo Sung; Lee, Sang Rin; Kang, Jong Soon; Kim, Hwan Mook; Lee, Kyung-Ae; Hong, Jin Tae; Kim, Youngsoo

    2010-01-01

    Background Lichen-derived glucans have been known to stimulate the functions of immune cells. However, immunostimulatory activity of glucan obtained from edible lichen, Umbilicaria esculenta, has not been reported. Thus we evaluated the phenotype and functional maturation of dendritic cells (DCs) following treatment of extracted glucan (PUE). Methods The phenotypic and functional maturation of PUE-treated DCs was assessed by flow cytometric analysis and cytokine production, respectively. PUE-treated DCs was also used for mixed leukocyte reaction to evaluate T cell-priming capacity. Finally we detected the activation of MAPK and NF-?B by immunoblot. Results Phenotypic maturation of DCs was shown by the elevated expressions of CD40, CD80, CD86, and MHC class I/II molecules. Functional activation of DCs was proved by increased cytokine production of IL-12, IL-1?, TNF-?, and IFN-?/?, decreased endocytosis, and enhanced proliferation of allogenic T cells. Polymyxin B, specific inhibitor of lipopolysaccharide (LPS), did not affect PUE activity, which suggested that PUE was free of LPS contamination. As a mechanism of action, PUE increased phosphorylation of ERK, JNK, and p38 MAPKs, and enhanced nuclear translocation of NF-?B p50/p65 in DCs. Conclusion These results indicate that PUE induced DC maturation via MAPK and NF-?B signaling pathways. PMID:21286379

  11. Influence of taro (Colocasia esculenta L. Shott) growth conditions on the phenolic composition and biological properties.

    PubMed

    Gonçalves, Rui F; Silva, Artur M S; Silva, Ana Margarida; Valentão, Patrícia; Ferreres, Federico; Gil-Izquierdo, Angel; Silva, João B; Santos, Delfim; Andrade, Paula B

    2013-12-15

    Colocasia esculenta (L.) Shott, commonly known as taro, is an essential food for millions of people. The leaves are consumed in sauces, purees, stews, and soups, being also used in wound healing treatment. Nowadays, the consumers' demand for bioactive compounds from the diet led to the development of new agricultural strategies for the production of health-promoting constituents in vegetables. In this work, two strategies (variety choice and irrigation conditions) were considered in the cultivation of C. esculenta. The effect on the phenolic composition of the leaves was evaluated. Furthermore, a correlation between the biological activity of the different varieties and their chemical composition was established. Qualitative and quantitative differences in the phenolic composition were observed between varieties; furthermore, the irrigation conditions also influenced the composition. C. esculenta varieties were able to scavenge several oxidant species and to inhibit hyaluronidase, but data suggest that metabolites other than phenolics are involved. The results show that cultivation strategies can effectively modulate the accumulation of these types of bioactive compounds. Furthermore C. esculenta wound healing potential can be attributed, at least in part, to the protection of the wound site against oxidative/nitrosative damage and prevention of hyaluronic acid degradation. PMID:23993510

  12. Photoproducts of carminic acid formed by a composite from Manihot dulcis waste.

    PubMed

    Antonio-Cisneros, Cynthia M; Dávila-Jiménez, Martín M; Elizalde-González, María P; García-Díaz, Esmeralda

    2015-04-15

    Carbon-TiO2 composites were obtained from carbonised Manihot dulcis waste and TiO2 using glycerol as an additive and thermally treating the composites at 800 °C. Furthermore, carbon was obtained from manihot to study the adsorption, desorption and photocatalysis of carminic acid on these materials. Carminic acid, a natural dye extracted from cochineal insects, is a pollutant produced by the food industry and handicrafts. Its photocatalysis was observed under different atmospheres, and kinetic curves were measured by both UV-Vis and HPLC for comparison, yielding interesting differences. The composite was capable of decomposing approximately 50% of the carminic acid under various conditions. The reaction was monitored by UV-Vis spectroscopy and LC-ESI-(Qq)-TOF-MS-DAD, enabling the identification of some intermediate species. The deleterious compound anthracene-9,10-dione was detected both in N2 and air atmospheres. PMID:25466082

  13. The genetic differentiation of Colocasia esculenta growing in gold mining areas with arsenic contamination.

    PubMed

    Boonmee, Sirilak; Neeratanaphan, Lamyai; Tanee, Tawatchai; Khamon, Prodpran

    2015-05-01

    Arsenic is a heavy metal found in contaminated gold mining areas and which can affect plant and animal species. This study aims to determine the concentration of As in the aquatic plant Colocasia esculenta as well as this plant's genetic variability. Sediment and C. esculenta samples were collected from three studied sites at the edge of a stream around a gold mine. The arsenic concentrations in sediment and C. esculenta samples were analyzed using induction coupled plasma-mass spectrometry (ICP-MS). Genetic differentiations were studied by random amplified polymorphic DNA (RAPD) with dendrogram construction and analysis of genetic similarity (S). The results showed that the arsenic concentrations in sediment and C. esculenta samples ranged from 4.547 ± 0.318 to 229.964 ± 0.978 and 0.108 ± 0.046 to 0.406 ± 0.174 mg kg(-1), respectively. To compare the samples studied to the reference site, RAPD fingerprints from 26 primers successfully produced 2301 total bands used for dendrogram construction and S value analysis. The dendrogram construction separates C. esculenta into four clusters corresponding to their sampling sites. The S values of the studied sample sites compared to the reference site are 0.676-0.779, 0.739-0.791, and 0.743-0.783 for sites 1, 2, and 3, respectively, whereas the values of the individuals within each site are as high as 0.980. These results suggest that As accumulation in aquatic plant species should be of concern because of the potential effects of As on aquatic plants as well as humans. PMID:25838064

  14. Determination of molecular weights and monosaccharide compositions in Abelmoschus manihot polysaccharides

    NASA Astrophysics Data System (ADS)

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

    2012-09-01

    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.

  15. Poisoning by Talisia esculenta (A. St.-Hil.) Radlk in sheep and cattle.

    PubMed

    Riet-Correa, Franklin; Bezerra, Cícero W; Medeiros, Marcia A; da Silva, Tatiane R; Neto, Eldinê G Miranda; Medeiros, Rosane M T

    2014-04-23

    Talisia esculenta is a tree that produces pitomba, a fruit consumed by human beings in several regions of Brazil. The current study reports 3 outbreaks of poisoning by leaves and fruits of T. esculenta affecting sheep and cattle and the experimental reproduction of the disease in sheep. In the first investigated outbreak, sheep ingested the leaves of the plant; another outbreak affected cattle and sheep that ingested leaves and fruits; and in a third outbreak, sheep ingested only the fruits. The animals developed severe nervous signs, but most recovered. Poisoning was reproduced experimentally in 5 sheep by the administration of 30-60 g of leaves/kg body weight and in 2 sheep with doses of 5 and 10 g of seeds/kg body weight, respectively. No significant necropsy or histologic lesions were found. PMID:24760131

  16. Comparative characterization of nucleotides, nucleosides and nucleobases in Abelmoschus manihot roots, stems, leaves and flowers during different growth periods by UPLC-TQ-MS/MS.

    PubMed

    Du, Le-yue; Qian, Da-wei; Jiang, Shu; Shang, Er-xin; Guo, Jian-ming; Liu, Pei; Su, Shu-lan; Duan, Jin-ao; Zhao, Min

    2015-12-01

    Nucleotides, nucleosides and nucleobases have been proven as important bioactive compounds related to many physiological processes. Abelmoschus manihot (L.) Medicus from the family of Malvaceae is an annual herbal plant of folk medicine widely distributed in Oceania and Asia. However, up to now, no detailed information could be available for the types and contents of nucleotides, nucleosides and nucleobases contained in A. manihot roots, stems, leaves as well as the flowers. In the present study, an UPLC-TQ-MS/MS method was established for detection of the twelve nucleotides, nucleosides and nucleobases. The validated method was successfully applied to identify the 12 analytes in different parts of A. manihot harvested at ten growth periods. 2'-deoxyinosine was not detected in all of the A. manihot samples. The data demonstrated that the distribution and concentration of the 12 compounds in A. manihot four parts were arranged in a decreasing order as leaf>flower>stem>root. Based on the results, the leaves and flowers of A. manihot could be developed as health products possessed nutraceutical and bioactive properties in the future. This method might also be utilized for the quality control of the A. manihot leaves and other herbal medicines being rich in nucleotides, nucleosides and nulecobases. PMID:26551204

  17. Further knowledge on the phenolic profile of Colocasia esculenta (L.) Shott.

    PubMed

    Ferreres, Federico; Gonçalves, Rui F; Gil-Izquierdo, Angel; Valentão, Patrícia; Silva, Artur M S; Silva, João B; Santos, Delfim; Andrade, Paula B

    2012-07-18

    Colocasia esculenta (L.) Shott, commonly called taro, is an ancient species selected for its edible tuber. Its huge "elephant ear" like leaves are also consumed in sauces and stews or as soups. Forty-one phenolic metabolites (11 hydroxycinnamic acid derivatives and 30 glycosylated flavonoids) were identified by high-performance liquid chromatography-diode array detection-electrospray ionization/mass spectrometry (HPLC-DAD-ESI/MS(n)) in the leaves of two C. esculenta varieties cultivated in Azores Islands. To our knowledge, 34 of the 41 phenolic compounds are being reported for the first time in this species. Phenolics quantification was achieved by an HPLC-DAD accurate and sensitive validated method. Although the qualitative profile of the two varieties is quite similar, quantitative differences were observed between them. "Giant white" and "red" varieties (local denomination) contain, respectively, ca. 14 and 21% of phenolic acids, 37 and 28% of flavones mono-C-glycosides, 42 and 43% of flavones di-C-glycosides, 3 and 4% of flavones mono-C-(O-glycosyl)glycosides, and both of them ca. 2% of flavones di-C-(O-glycosyl)glycosides and 2% of flavones-O-glycosides. Luteolin-6-C-hexoside was the compound present in higher amounts in both varieties. The established phenolic profile is an added value for the authenticity and quality control of C. esculenta and may be useful in the discrimination of its varieties. PMID:22724554

  18. Inhibitory effects of Colocasia esculenta (L.) Schott constituents on aldose reductase.

    PubMed

    Li, Hong Mei; Hwang, Seung Hwan; Kang, Beom Goo; Hong, Jae Seung; Lim, Soon Sung

    2014-01-01

    The goal of this study was to determine the rat lens aldose reductase-inhibitory effects of 95% ethanol extracts from the leaves of C. esculenta and, its organic solvent soluble fractions, including the dichloromethane (CH2Cl2), ethyl acetate (EtOAc), n-butanol (BuOH) and water (H2O) layers, using dl-glyceraldehyde as a substrate. Ten compounds, namely tryptophan (1), orientin (2), isoorientin (3), vitexin (4), isovitexin (5), luteolin-7-O-glucoside (6), luteolin-7-O-rutinoside (7), rosmarinic acid (8), 1-O-feruloyl-d-glucoside (9) and 1-O-caffeoyl-d-glucoside (10) were isolated from the EtOAc and BuOH fractions of C. esculenta. The structures of compounds 1-10 were elucidated by spectroscopic methods and comparison with previous reports. All the isolates were subjected to an in vitro bioassay to evaluate their inhibitory activity against rat lens aldose reductase. Among tested compounds, compounds 2 and 3 significantly inhibited rat lens aldose reductase, with IC50 values of 1.65 and 1.92 μM, respectively. Notably, the inhibitory activity of orientin was 3.9 times greater than that of the positive control, quercetin (4.12 μM). However, the isolated compounds showed only moderate ABTS+ [2,29-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)] activity. These results suggest that flavonoid derivatives from Colocasia esculenta (L.) Schott represent potential compounds for the prevention and/or treatment of diabetic complications. PMID:25255750

  19. Efficiency of Colocasia esculenta leaves extract and histopathological effects on Culex pipiens (Diptera: Culicidae).

    PubMed

    El-Monairy, Olfat M

    2015-04-01

    This study evaluated the toxicity of Colocasia esculenta leaves extract on 3rd, 4th instars larvae and pupae of Culex pipiens. Bioassays showed that the 3rd instar larvae was the most susceptible to the different concentrations of extract, where the LC50 after 48 hr. post-exposure was 79.41, 109.65 & 141.25 for the 3rd, 4th instars larvae and pupal stage respectively. The histo-pathological effects of C. esculenta leaves extract on midgut regions and gastric caeca of the 3rd instar larvae were studied. When larvae were treated with 100 ppm of C. esculenta extract, all larvae developed dramatic pathological lesions especially Malpighian tubules were extensively affected. The midgut cells showed morphological deviation from normal ones, through slightly apical degenerated (lysis) of epithelial cells. The epithelial cells with extensive cellular microvilli were shrinkage, the nuclei showed pyknotic characteristic and the peritrophic membrane was appeared discontinuation in compared to control. When the 3rd larval instar was exposed to extract 400 ppm, the epithelial cells, adipose fabric and muscles were extensively affected. Also, the gastric caeca was affected obviously. These observation and alterations in cells of Cx. pipiens larvae are related to the dangerous effect of C. esculent leaves extract. PMID:26012222

  20. In situ visualization of o-phthalate esters in gastrointestinal tract of the frog Rana esculenta.

    PubMed

    Menghi, G; Marchetti, L; Sabbieti, M G; Menghi, M; Materazzi, S

    2003-04-01

    The regional distribution and relative occurrence of phthalates were studied immunohistochemically by confocal laser scanning microscopy in the alimentary tract of the green frog, Rana esculenta, using an antibody against o-phthalate esters. Many positive sites indicating the basal presence of phthalate esters were identified. The immunoreactive cells were located in the gastric glands of the stomach and in the intestinal epithelium regions with variable frequencies. The regional distribution of phathalate-accumulating cells resembled that of fish and demonstrated that these endocrine disruptors not only enter via the alimentary canal, but also bioaccumulate inside cells specialized in secretion as well as absorption functions. PMID:12647786

  1. Distribution of wild taro (Colocasia esculenta) in subtropical Texas, growth of young colonies, and tolerance to simulated herbivory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Non-native wild taro (Colocasia esculenta) is an ornamental plant that is an emerging invasive weed in moist riparian areas in subtropical and warm temperate river systems in Texas, with potential impacts on native plant species, habitat quality and water use in the Lower Rio Grande Basin. Observati...

  2. First report of taro vein chlorosis virus infecting taro [Colocasia esculenta (L.) Schott] in the United States of America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In March 2013, taro plants [Colocasia esculenta (L.) Schott cv. ‘iliuaua’] with leaves displaying veinal chlorosis and necrosis were observed at a germplasm collection on the island of Molokai. These symptoms were similar to those of taro vein chlorosis, an important disease of taro found in severa...

  3. Hexavalent chromium removal from aqueous solutions by a novel powder prepared from Colocasia esculenta leaves.

    PubMed

    Nakkeeran, E; Saranya, N; Giri Nandagopal, M S; Santhiagu, A; Selvaraju, N

    2016-08-01

    In this study, batch removal of hexavalent chromium from aqueous solutions by powdered Colocasia esculenta leaves was investigated. Batch experiments were conducted to study the effects of adsorption of Cr(VI) at different pH values, initial concentrations, agitation speeds, temperatures, and contact times. The biosorbent was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectrometer analysis. The biosorptive capacity of the adsorbent was dependent on the pH of the chromium solution in which maximum removal was observed at pH 2. The adsorption equilibrium data were evaluated for various adsorption isotherm models, kinetic models, and thermodynamics. The equilibrium data fitted well with Freundlich and Halsey models. The adsorption capacity calculated was 47.62 mg/g at pH 2. The adsorption kinetic data were best described by pseudo-second-order kinetic model. Thus, Colocasia esculenta leaves can be considered as one of the efficient and cheap biosorbents for hexavalent chromium removal from aqueous solutions. PMID:26853060

  4. [Enrichment of Cd2+ and Hg2+ in Phascolosoma esculenta and their effects].

    PubMed

    Wu, Hong-xi; Gao, Ye-tian; Huang, Zhen-hua; Jiang, Xia-min

    2015-06-01

    The accumulation of Cd2+ and Hg2+ in Phascolosoma esculenta and its effects on its growth and main nutrient components were investigated using atomic absorption spectrometer analysis and atomic fluorescence spectrometer examination. The results showed that within the experimental heavy metal concentrations, the amounts of Cd2+ and Hg2+ accumulated in the somatic muscles increased with increasing exposure time and reached their saturated levels at the end of the experiment. Exposure of higher heavy metal concentrations speeded up the accumulation of Cd2+ and Hg2+ and subsequently took less time to reach their saturated levels, which were greater than those of lower concentration groups. The rate of mass gain of P. esculenta decreased with increasing the heavy metal exposure concentrations. The combination exposure of Cd2+ and Hg2+ led to a significantly lower mass gain rate compared to those exposed to Cd2+ or Hg2+. The protein content of somatic muscles increased with the increase of exposure concentration and reached the maximum values at 0.05 and 0.02 mg · L(-1) for Cd2+ and Hg2+, respectively. After that, the protein content of somatic muscles began to decrease. The combined exposure of the two heavy metals showed similar effect trends but more significant impacts on the protein content of somatic muscles. The lipid content of somatic muscles decreased with increasing the concentration of Cd2+ or Hg2+ exposure, and the combination of Cd2+ and Hg2+ led to lower lipid content. PMID:26572044

  5. A first assessment of genetic variation among Morchella esculenta (morel) populations.

    PubMed

    Dalgleish, H J; Jacobson, K M

    2005-01-01

    Habitat loss and fragmentation have serious consequences for species diversity as well as genetic diversity within a species. As the most sought-after culinary fungus in the Midwest United States, morels (Morchella esculenta and related species) demand the attention of conservationists interested in preserving biological and genetic diversity. Little is known about the natural history of M. esculenta, which is critical information for understanding population dynamics as well as the impacts of habitat fragmentation and harvesting. We report initial results from our long-term studies of genetic variability among fruiting bodies at the Conard Environmental Research Area at Grinnell College, Grinnell, Iowa. Using random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR), a technique that has been successfully used to examine intrapopulation structure and detect clonal populations in numerous fungi, we found substantially higher levels of genetic polymorphism among 57 fruiting bodies than has been previously reported. Though laboratory studies indicate that the inbreeding potential for this fungus is high, we found little evidence for inbreeding, with only two pairs of the randomly chosen isolates having identical genotypes at the 34 loci examined. This work highlights the importance of further attempts to resolve important aspects of the morel life cycle regarding heterokaryosis and inbreeding potential. PMID:15788743

  6. 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...

  7. 7 CFR 319.56-13 - Fruits and vegetables allowed importation subject to specified conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... melo var. cantaloupensis Fruit (b)(1)(v), (b)(3). Cassava Manihot esculenta Fruit (b)(2)(vii). Honeydew...), (b)(5)(vi). Togo Pineapple Ananas comosus Fruit (b)(2)(vi). Trinidad and Tobago Cassava Manihot esculenta Fruit (b)(2)(vi). Cucurbit Cucurbitaceae Above ground parts (b)(2)(iii), (b)(3). Papaya...

  8. 2, 3-Dimethylmaleic anhydride (3, 4-Dimethyl-2, 5-furandione): A plant derived insecticidal molecule from Colocasia esculenta var. esculenta (L.) Schott

    PubMed Central

    Rajashekar, Yallappa; Tonsing, Ngaihlun; Shantibala, Tourangbam; Manjunath, Javagal R.

    2016-01-01

    The phasing out of methyl bromide as a fumigant, resistance problems with phosphine and other fumigants in stored product beetles, and serious concern with human health and environmental safety have triggered the search for alternative biofumigants of plant origin. Despite the identification of a large number of plants that show insecticidal activity, and the diversity of natural products with inherent eco-friendly nature, newer biofumigants of plant origin have eluded discovery. Using a bioassay driven protocol, we have now isolated a bioactive molecule from the root stock of Colocasia esculenta (L.) and characterized it as 2, 3-dimethylmaleic anhydride (3, 4-dimethyl-2, 5-furandione) based on various physico-chemical and spectroscopic techniques (IR, 1H NMR, 13C NMR and Mass). The molecule proved to be an efficient biofumigant which is highly toxic to insect pests for stored grains even at very low concentration, but has no adverse effect on seed germination. We finally address the potential for this molecule to become a, effective biofumigant. PMID:26837840

  9. 2, 3-Dimethylmaleic anhydride (3, 4-Dimethyl-2, 5-furandione): A plant derived insecticidal molecule from Colocasia esculenta var. esculenta (L.) Schott.

    PubMed

    Rajashekar, Yallappa; Tonsing, Ngaihlun; Shantibala, Tourangbam; Manjunath, Javagal R

    2016-01-01

    The phasing out of methyl bromide as a fumigant, resistance problems with phosphine and other fumigants in stored product beetles, and serious concern with human health and environmental safety have triggered the search for alternative biofumigants of plant origin. Despite the identification of a large number of plants that show insecticidal activity, and the diversity of natural products with inherent eco-friendly nature, newer biofumigants of plant origin have eluded discovery. Using a bioassay driven protocol, we have now isolated a bioactive molecule from the root stock of Colocasia esculenta (L.) and characterized it as 2, 3-dimethylmaleic anhydride (3, 4-dimethyl-2, 5-furandione) based on various physico-chemical and spectroscopic techniques (IR, (1)H NMR, (13)C NMR and Mass). The molecule proved to be an efficient biofumigant which is highly toxic to insect pests for stored grains even at very low concentration, but has no adverse effect on seed germination. We finally address the potential for this molecule to become a, effective biofumigant. PMID:26837840

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

    PubMed

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

    2002-06-01

    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

  11. Polysaccharides from Umbilicaria esculenta cultivated in Huangshan Mountain and immunomodulatory activity.

    PubMed

    Du, Yi-Qun; Liu, Yong; Wang, Jun-Hui

    2015-01-01

    Umbilicaria esculenta cultivated in Huangshan Mountain (HSSE) is precious edible and medicinal lichen. In this study, four polysaccharide fractions designated as UEP1, UEP2, UEP3, and UEP4 were isolated from HSSE with water extraction at different temperature. The physico-chemical properties and immunomodulatory activities of polysaccharide fractions were investigated. The results indicated that UEP1, UEP2, UEP3 and UEP4 were acid polysaccharide with 0.50%, 0.62%, 0.63%, and 0.83% of uronic acid contents, respectively. Four polysaccharide fractions were mainly composed of glucose, galactose and mannose with different molar ratio. In the in vitro immunomodulatory assay, all the polysaccharide fractions (20-500 μg/mL) could increase the NO production and phagocytic activity of RAW 264.7 cells in a dose-dependent manner. This work demonstrated that the polysaccharides from HSSE could be used as potential biological response modifier. PMID:25316425

  12. Histological and histochemical analyses of the cuttlebone sac of the golden cuttlefish Sepia esculenta

    NASA Astrophysics Data System (ADS)

    Zheng, Xiaodong; Xiao, Shu; Wang, Zhaoping; Wang, Rucai

    2007-10-01

    The secretion function of mantle is closely related to shell formation in some bivalves and gastropods. Up to now, few researches have been reported for cuttlebone formation in the class Cephalopoda. In this study, the structure and secretion function of cuttlebone sac of the golden cuttlefish Sepia esculenta was analyzed using the histological and histochemical methods. The results showed that high and columnar cells located in sac epithelium, and flat cells existed near the base membrane. A lot of fibroblasts were found in the lateral mantle collective tissue. Some mucus, mucopolysaccharide and alkaline phosphatase (ALP) were found in the sac. The ultrastructural characteristics of Quasi-connective-tissue-calcium cells (QCTCC) were observed using a transmission electron microscope (TEM). The relationship between cuttlebone sac secretion function and shell formation was discussed.

  13. Granulopoiesis in tadpoles of Rana esculenta. Survey of the organs involved.

    PubMed Central

    Frank, G

    1988-01-01

    The topography and nature of granulopoietic tissues appearing during the larval period of Rana esculenta have been investigated using light and electron microscopy. The formation of eosinophils and heterophils occurred in the interstices of the pronephros and opisthonephros, in the mesenchymal sheath surrounding the pronephric duct, as well as in the mesentery and mesenchymal coat of the bile duct and hepatic ducts. Developing basophils were very rare, being detectable only in the stroma of the trunk kidneys. The pronephric interstices additionally contained differentiating lymphocytes, the opisthonephric interstices differentiating lymphocytes and erythrocytes. In contrast, the mesenchymal sheath of the pronephric duct as well as the mesentery and the mesenchymatous coat of the bile duct and hepatic ducts were solely granulopoietic. Images Fig. 1 Figs. 2-3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:3267013

  14. Variation of mineral composition in different parts of taro (Colocasia esculenta) corms.

    PubMed

    Mergedus, Andrej; Kristl, Janja; Ivancic, Anton; Sober, Andreja; Sustar, Vilma; Krizan, Tomaz; Lebot, Vincent

    2015-03-01

    Taro (Colocasia esculenta) is an important root crop in the humid tropics and a valuable source of essential mineral nutrients. In the presented study, we compared the mineral compositions of four main parts of taro corm: the upper, marginal, central and lower (basal) parts. The freeze-dried taro samples were analysed for eleven minerals (K, P, Mg, Ca, Zn, Fe, Mn, Cu, Cd, Pb and Cr). The upper part, which plays a critical role in vegetative propagation based on headsets, contained high levels of P, Mg, Zn, Fe, Mn, Cu and Cd. The central part, which is essential for human nutrition, was characterised by higher concentrations of K, P, Mg, Zn, Fe, Cu and Cd. Ca was concentrated in the lower and marginal parts. The effect of the genotype was significant for more than half of the analysed minerals (i.e., Mg, Ca, Zn, Fe, Mn). PMID:25306315

  15. Effects of temperature fluctuations on cuttlebone formation of cuttlefish Sepia esculenta

    NASA Astrophysics Data System (ADS)

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

    2012-07-01

    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.

  16. Granulopoiesis in tadpoles of Rana esculenta. Ultrastructural observations on the developing granulocytes and on the development of eosinophil granules.

    PubMed Central

    Frank, G

    1989-01-01

    The morphology and development of the granules of developing eosinophils present in the trunk kidneys of Rana esculenta tadpoles has been studied at the ultrastructural level. During the differentiation of eosinophil granulocytes a single and morphologically unique population of cytoplasmic granules is present. Fully developed granules are spherical, membrane-limited, and have a dense and homogeneous content. Eosinophil granules have been traced back to Golgi-derived vacuoles which fuse and form immature granules containing a dense and knot-like precipitate. By condensation these immature granules transform into the definitive homogeneous forms. The eosinophil granules of Rana esculenta are compared to those in other vertebrates and possible phylogenetic aspects are discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 PMID:2606785

  17. Aibika (Abelmoschus manihot L.): Genetic variation, morphology and relationships to micronutrient composition.

    PubMed

    Rubiang-Yalambing, Lydia; Arcot, Jayashree; Greenfield, Heather; Holford, Paul

    2016-02-15

    Aibika (Abelmoschus manihot L.) is believed to be a good source of micronutrients. However, although many varieties of aibika are commonly consumed in Papua New Guinea, their micronutrient content is unknown. Therefore, the mineral (Ca, Fe, K, Mg, Mn, Na, Zn & Cu), folate composition and the genetic variation of 23 aibika accessions from the collection at the National Agricultural Research Institute were studied over a 3year period to provide data for nutritional studies and to inform breeding programs. The data showed that aibika is, potentially, a crop of high nutritional value with the potential to boost the micronutrient status of local PNG communities. However, there were substantial differences in the micronutrient concentrations of the accessions from year to year and accessions that had the highest concentration of a particular mineral in 1year did not have the high concentrations in other years. Clusters determined using unweighted pair group method with arithmetic mean analysis (UPGMA) of the micronutrient contents differed in each of the 3years. Genetic analysis made using random amplification of polymorphic DNA and directed amplification of mini satellite region DNA placed the accessions into five groups. There was no correlation between these groups and leaf morphology, nor were there correlations with the clusters determined from the UPGMA analyses. There appears to be considerable interaction between genotype and environmental factors determining micronutrient composition and environmental factors may play a greater role than genotype in influencing micronutrient composition. PMID:26433288

  18. Antimicrobial, antioxidant and cytotoxicity potential of Manihot multifida (L.) Crantz (Euphorbiaceae).

    PubMed

    Fabri, Rodrigo L; De Sá, Daniel S; Pereira, Ana Patrícia O; Scio, Elita; Pimenta, Daniel S; Chedier, Luciana M

    2015-03-01

    Manihot multifida (L.) Crantz (Euphorbiaceae) is widely used in popular medicine for the treatment of infected wounds. This study evaluated the in vitro antioxidant and antimicrobial potential of this species against strains of Gram-positive and Gram-negative bacteria and fungi, known to cause infections in humans. The extracts showed minimal inhibitory concentration (MIC) varying from 39 to 2500 µg/mL for antimicrobial activity. The methanolic extract of fruits, aqueous and hexane extracts of leaves showed a very strong activity against Candida albicans (ATCC 18804) with MIC of 39 µg/mL. Furthermore, the methanolic extract of M. multifida leaves exhibited DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging potential with inhibitory concentration (IC50) values of 46.9 μg/mL, followed by hexane extract of leaves with IC50 values of 59.2 μg/mL. The cytotoxic activity against brine shrimp was stronger for the methanolic extract of leaves (lethal concentration - LC50 of 15.6 µg/mL). These results suggest that M. multifida has interesting antimicrobial and antioxidant activities. Moreover, these results corroborate the popular use of this specie in treating fungal infections since it demonstrates significant activity against C. albicans. PMID:25714074

  19. Diversity in oil content and fatty acid profile in seeds of wild cassava germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. Effects of Amendments on Growth and Uptake of Cd and Zn by Wetland Plants, Typha angustifolia and Colocasia esculenta from Contaminated Sediments.

    PubMed

    Chayapan, P; Kruatrachue, M; Meetam, M; Pokethitiyook, P

    2015-01-01

    A pot study was conducted to compare the effects of amendments (CaHPO4 and cow manure) on growth and uptake of Cd and Zn from contaminated sediments by two wetland plant species, Typha angustifolia and Colocasia esculenta. Contaminated sediments (Cd 33.2 mg kg(-1) and Zn 363 mg kg(-1)) were collected from Mae Tao basin, Mae Sot district, Tak province, Thailand. The experiment consisted of 4 treatments: control (uncontaminated sediment), Cd/Zn, Cd/Zn + 5% CaHPO4, and Cd/Zn + 10% cow manure. Plants were grown for 3 months in the greenhouse. The addition of CaHPO4 resulted in the highest relative growth rate (RGR) and highest Cd accumulation in both T. angustifolia and C. esculenta while the lowest RGR was found in C. esculenta grown in the cow manure treatment. Both plant species had higher concentrations of metals (Cd, Zn) in their belowground parts. None of the amendments affected Zn accumulation. C. esculenta exhibited the highest uptake of both Cd and Zn. The results clearly demonstrated the phytoremediation potential of C. esculenta and the enhancement of this potential by CaHPO4 amendment. PMID:25831275

  1. Modeling Foliar Uptake in Colocasia Esculenta Using High Resolution Maps of Leaf Water Isotopes

    NASA Astrophysics Data System (ADS)

    Sinkler, C. J.; Gerlein-Safdi, C.; Caylor, K. K.

    2014-12-01

    The uptake of carbon dioxide by vegetation is a major sink of CO2 and a factor that will determine future climate. Some studies predict a decrease in CO2 uptake from vegetation because of a general drying of the Amazon Basin. Because of the tight linkage between water availability and plant carbon uptake, a comprehensive model of plant water use at the individual scale is necessary to build a complete carbon budget at the global scale. Foliar uptake of non-meteoric water is a common process used by plants to alleviate water stress. However the occurrence of this process in tropical ecosystems, as well as its interaction with other physiological parameters, is not well understood. We present a model of leaf water balance that includes foliar uptake. The isotopic composition of the different sources as well as the leaf water are also included. The model is tested against a series of experiments on Colocasia esculenta, under two different water availability conditions: drought and artificial dew. The artificial dew is spiked with stable isotopes of water (δ18O = 8.56 permil, δ2H = 709.7 permil) that allow us to trace the partition of dew uptake within a leaf. We create high-resolution maps of the distribution of isotopes in one half of each leaf using a Picarro IM-CRDS. The maps show a clear enrichment due to foliar uptake for the artificial dew treatment. The water in the second half of the leaf is extracted by cryogenic extraction and analyzed using both IRIS and IRMS for quality control of the IM-CRDS data. Soil water is collected for isotope analysis and water content measurement. Finally, stomatal conductance data collected every two days shows no significant decrease due to either treatment over the course of the experiment. We conclude that foliar uptake of dew water is an important water acquisition mechanism for C. esculenta, even under high soil water content conditions, and we propose guidelines for further improvement of models of leaf-scale water balance.

  2. Metabolite identification strategy of non-targeted metabolomics and its application for the identification of components in Chinese multicomponent medicine Abelmoschus manihot L.

    PubMed

    Guo, Jian-ming; Lu, Yu-wei; Shang, Er-xin; Li, Ting; Liu, Yang; Duan, Jin-ao; Qian, Da-wei; Tang, Yu-ping

    2015-05-15

    Identification of multicomponent in traditional Chinese medicine (TCM) is complex and time-consuming. The inspection of the full-scan mass chromatograms was usually performed manually, which is labor-intensive. It is difficult to distinguish low response signals from complex chemical background. Furthermore, this process is typically based on earlier knowledge of the chemical composition of TCM, and those molecules that have not been characterized earlier were thus ignored. In this paper, a strategy using UPLC-MS combined with pattern recognition analysis was developed to simplify and quicken the identification of multicomponent in Abelmoschus manihot (L.) Medik. First, complex signals obtained by UPLC-MS were processed using automated data mining algorithm and further processed with multivariate chemometric methods. Multicomponent in Abelmoschus manihot L. can be clearly displayed in S- and VIP-plot. Using this method, 320 peaks which present in Abelmoschus manihot L. were detected. In the next step, accurate mass spectra of the characteristic markers acquired by QTOF MS were used to estimate their elemental formulae and enable structure identification. By searching in METLIN database, 41 components were tentatively identified in Abelmoschus manihot L. Our results showed that UPLC-MS based-pattern recognition analysis approach can be used to quickly identify TCM multicomponent and for standardization of herbal preparations. PMID:25981925

  3. Phytoremediation of Landfill Leachate with Colocasia esculenta, Gynerum sagittatum and Heliconia psittacorum in Constructed Wetlands.

    PubMed

    Madera-Parra, C A; Peña-Salamanca, E J; Peña, M R; Rousseau, D P L; Lens, P N L

    2015-01-01

    This study assessed the accumulation of Cd (II), Hg (II), Cr (VI) and Pb (II) in Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) planted in constructed wetlands treating synthetic landfill leachate. Sixteen bioreactors were operated in two experimental blocks. Metal concentrations in the influent and effluent; root, stem, branch and leaves of plants were analysed, as well as COD, N-NH4+, TKN, T, pH, ORP, DO, and EC. Average removal efficiencies of COD, TKN and NH4+-N were 66, 67 and 72%, respectively and heavy metal removal ranged from 92 to 98% in all units. Cr (VI) was not detected in any effluent sample. The bioconcentration factors (BCF) were 10(0) -10(2). The BCF of Cr (VI) was the lowest: 0.59 and 2.5 (L kg(-1)) for Gs and He respectively; whilst Cd (II) had the highest (130-135 L kg(-1)) for Gs. Roots showed a higher metal content than shoots. Translocation factors (TF) were lower, He was the plant exhibiting TFs>1 for Pb (II), Cr (T) and Hg (II) and 0.4-0.9 for Cd (II) and Cr (VI). The evaluated plants demonstrate their suitability for phytoremediation of landfill leachate and all of them can be categorized as metals accumulators. PMID:25174421

  4. Molecular Mechanism Underlying the Entomotoxic Effect of Colocasia esculenta Tuber Agglutinin against Dysdercus cingulatus

    PubMed Central

    Roy, Amit; Das, Sampa

    2015-01-01

    Colocasia esculenta tuber agglutinin (CEA), a mannose binding lectin, exhibits insecticidal efficacy against different hemipteran pests. Dysdercus cingulatus, red cotton bug (RCB), has also shown significant susceptibility to CEA intoxication. However, the molecular basis behind such entomotoxicity of CEA has not been addressed adequately. The present study elucidates the mechanism of insecticidal efficacy of CEA against RCB. Confocal and scanning electron microscopic analyses documented CEA binding to insect midgut tissue, resulting in an alteration of perimicrovillar membrane (PMM) morphology. Internalization of CEA into insect haemolymph and ovary was documented by western blotting analyses. Ligand blot followed by mass spectrometric identification revealed the cognate binding partners of CEA as actin, ATPase and cytochrome P450. Deglycosylation and mannose inhibition assays indicated the interaction to probably be mannose mediated. Bioinformatic identification of putative glycosylation or mannosylation sites in the binding partners further supports the sugar mediated interaction. Correlating entomotoxicity of CEA with immune histological and binding assays to the insect gut contributes to a better understanding of the insecticidal potential of CEA and endorses its future biotechnological application.

  5. The melanogenic system of the liver pigmented macrophages of Rana esculenta L.--tyrosinase activity.

    PubMed

    Gallone, A; Sagliano, A; Guida, G; Ito, S; Wakamatsu, K; Capozzi, V; Perna, G; Zanna, P; Cicero, R

    2007-10-01

    The enzyme system responsible for Amphibian Kupffer Cell (KC) melanogenesis has not been entirely elucidated. This research demonstrates that the KC melanosomes of Rana esculenta L. possess a tyrosine-hydroxylase (TH) activity, showing that a tyrosinase is the enzyme involved in the melanogenesis. The TH reaction depends on catalytic Dopa as a cofactor and is not affected by catalase or H2O2, showing that it is catalysed by the tyrosinase and not by the peroxidase present in the melanosomes. The TH reaction is activated by Cu2+ ions but not by other tyrosinase activators such as limited proteolysis, protein ageing, and Sodium Dodecyl Sulphate (SDS). SDS inhibited the KC TH activity even below the critical micelle concentration. All these results suggest that the KC-tyrosinase differs in structure from other known tyrosinases. Using anti-KC-tyrosinase antobodies, we observed that the sites of the tyrosinase location within the cell are the same as those described in the melanocytes. In the immunoblots, the anti-KC-tyrosinase antibodies also recognised two protein bands, at the higher molecular weight ranges, in the protein electrophoretic pattern. Moreover, the tyrosinase activity was limited to the highest molecular weight band of about 260 kDa, suggesting that the enzyme activity could depend on a molecular aggregate. The melanin produced in the liver was found to be a 5,6-dihydroxyindole-rich eumelanin similar to the Sepia melanin. PMID:17616933

  6. Antihypertensive and Diuretic Effects of the Aqueous Extract of Colocasia esculenta Linn. Leaves in Experimental Paradigms

    PubMed Central

    Vasant, Otari Kishor; Vijay, Bhalsing Gaurav; Virbhadrappa, Shete Rajkumar; Dilip, Nandgude Tanaji; Ramahari, Mali Vishal; Laxamanrao, Bodhankar Subhash

    2012-01-01

    Colocasia esculenta Linn (CE) is traditionally used for the treatment of various ailments such as high blood pressure, rheumatic pain, pulmonary congestion, etc. Hence in present study, the effect of aqueous extract of CE leaves (AECE) was evaluated for antihypertensive and acute diuretic activity in rats. Preliminary phytochemical evaluation revealed the presence of carbohydrate, saponins, tannins, and flavonoids in AECE. The animals did not show any sign of toxicity and mortality after the administration of AECE 2000 mg/Kg in acute oral toxicity study. The administration of AECE (100, 200, and 400 mg/Kg/day, p.o.) for six weeks and AECE (10, 20, and 40 mg/Kg, IV) on the day of experiment in renal artery-occluded hypertensive rats and AECE (20 and 40 mg/Kg, IV) in noradrenalin-induced hypertension in rats produced significant (p < 0.05) anti-hypertensive effects. AECE (400 mg/Kg, p.o.) showed positive diuretic activity at 5 h. AECE (200 and 400 mg/Kg, p.o.) significantly increased sodium and chloride content of urine in 5 h and 24 h and additionally potassium in 24 h urine. Hence, the results of the present study revealed the antihypertensive and weak diuretic activity of AECE. These effects may be attributed due to the ACE inhibitory, vasodilatory, β-blocking, and/ or Ca2+ channel blocking activities, which were reported for the phytoconstitunts, specifically flavonoids such as vitexin, isovitexin, orientin, and isoorientin present in the leaves of CE. PMID:24250487

  7. D-Asp: a new player in reproductive endocrinology of the amphibian Rana esculenta.

    PubMed

    Raucci, Franca; Di Fiore, Maria Maddalena

    2011-11-01

    We investigated the involvement of D-Aspartic acid (D-Asp) on ovarian and testicular morphology of the green frog, Rana esculenta, and its effect on the testosterone production. The study has been performed throughout the reproductive cycle. In both ovary and testis a substantial amount of D-Asp is endogenously present and its concentration varies as function of reproduction. In the frog, D-Asp content is differently correlated with gonadal and plasmatic levels of testosterone, depending on the sex. In fact, the amount of the D-Asp is inversely linked with that of the testosterone in the ovary, while this correlation directly matched in the testis. In vivo short-term experiments, consisting of a single intra-peritoneal injection of D-Asp (2.0 μmol/g body weight), demonstrated that the enantiomer is significantly accumulated by both the ovary and testis, reaching after 3 h the highest uptake and thereafter decreasing to baseline values within 24 h. Furthermore, D-Asp influences the synthesis and/or the release of testosterone, causing a decrease of its level in the female, and an increase in the male, respectively. In vivo long-term experiments, D-Asp, chronically administered to the frogs of both sexes, enhances the maturation of both gonads, determining in the oocytes an higher accumulation of carbohydrate yolk plates in the ooplasm, and stimulating the spermatogenesis in the testis. Taken altogether, our results show that D-Asp operates differently in female and male frog gonads, indicating that it has different targets in the reproductive machinery depending on the sex. PMID:21531634

  8. Antihypertensive and Diuretic Effects of the Aqueous Extract of Colocasia esculenta Linn. Leaves in Experimental Paradigms.

    PubMed

    Vasant, Otari Kishor; Vijay, Bhalsing Gaurav; Virbhadrappa, Shete Rajkumar; Dilip, Nandgude Tanaji; Ramahari, Mali Vishal; Laxamanrao, Bodhankar Subhash

    2012-01-01

    Colocasia esculenta Linn (CE) is traditionally used for the treatment of various ailments such as high blood pressure, rheumatic pain, pulmonary congestion, etc. Hence in present study, the effect of aqueous extract of CE leaves (AECE) was evaluated for antihypertensive and acute diuretic activity in rats. Preliminary phytochemical evaluation revealed the presence of carbohydrate, saponins, tannins, and flavonoids in AECE. The animals did not show any sign of toxicity and mortality after the administration of AECE 2000 mg/Kg in acute oral toxicity study. The administration of AECE (100, 200, and 400 mg/Kg/day, p.o.) for six weeks and AECE (10, 20, and 40 mg/Kg, IV) on the day of experiment in renal artery-occluded hypertensive rats and AECE (20 and 40 mg/Kg, IV) in noradrenalin-induced hypertension in rats produced significant (p < 0.05) anti-hypertensive effects. AECE (400 mg/Kg, p.o.) showed positive diuretic activity at 5 h. AECE (200 and 400 mg/Kg, p.o.) significantly increased sodium and chloride content of urine in 5 h and 24 h and additionally potassium in 24 h urine. Hence, the results of the present study revealed the antihypertensive and weak diuretic activity of AECE. These effects may be attributed due to the ACE inhibitory, vasodilatory, β-blocking, and/ or Ca(2+) channel blocking activities, which were reported for the phytoconstitunts, specifically flavonoids such as vitexin, isovitexin, orientin, and isoorientin present in the leaves of CE. PMID:24250487

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

    PubMed Central

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

    2011-01-01

    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 <  .01) in phenolic compounds (i.e., gallic acid, catechin, hydroxybenzioc acid and ρ-coumaric acid) across populations. This study provides evidences to establish that consumption of M. 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. PMID:21785629

  10. High bioethanol titre from Manihot glaziovii through fed-batch simultaneous saccharification and fermentation in Automatic Gas Potential Test System.

    PubMed

    Moshi, Anselm P; Crespo, Carla F; Badshah, Malik; Hosea, Kenneth M M; Mshandete, Anthony Manoni; Mattiasson, Bo

    2014-03-01

    A process for the production of high bioethanol titre was established through fed-batch and simultaneous saccharification and fermentation (FB-SSF) of wild, non-edible cassava Manihot glaziovii. FB-SSF allowed fermentation of up to 390g/L of starch-derived glucose achieving high bioethanol concentration of up to 190g/L (24% v/v) with yields of around 94% of the theoretical value. The wild cassava M. glaziovii starch is hydrolysable with a low dosage of amylolytic enzymes (0.1-0.15% v/w, Termamyl® and AMG®). The Automatic Gas Potential Test System (AMPTS) was adapted to yeast ethanol fermentation and demonstrated to be an accurate, reliable and flexible device for studying the kinetics of yeast in SSF and FB-SSF. The bioethanol derived stoichiometrically from the CO2 registered in the AMPTS software correlated positively with samples analysed by HPLC (R(2)=0.99). PMID:24534761

  11. Microanatomy and ultrastructure of outer mantle epidermis of the cuttlefish, Sepia esculenta (Cephalopoda: Sepiidae).

    PubMed

    Lee, Dong Geun; Park, Min Woo; Kim, Byeong Hak; Kim, Hyejin; Jeon, Mi Ae; Lee, Jung Sick

    2014-03-01

    This study describes the ultrastructural characteristics of external epidermis of mantle of Sepia esculenta using light and electron microscopy. The epidermis was thicker on the ventral surface than on the dorsal surface, with a higher secretory cell distribution on the ventral surface than on the dorsal surface. The epidermis was a single layer composed of epithelial cells, secretory cells, ciliated cells and neuroglial cells. Epithelial cells were columnar with well-developed microvilli on the free surface, and the microvilli were covered with glycocalyx. The epithelial cells were connected to the neighboring cells by tight junctions and membrane interdigitations of the apico-frontal surface. Well-developed microfilaments were arranged in a vertical direction in the cortical cytoplasm. The secretory cells were categorized into three types (A, B and C) in accordance with the light microscopical characteristics and ultrastructures of the secretory granules. The distribution of these cells was in the following order: Type A>Type B>Type C. SEM observation revealed that the secretory pore size of the Type A secretory cells was approximately 8.6 μm×12.2 μm. Cytoplasm displayed a red color as the result of Masson's trichrome stain and H-E stain, and contained polygonal granules of approximately 1.2 μm2 with a high electron density. The secretory pore size of the Type B secretory cells was approximately 10.1 μm×12.1 μm. As the results of AB-PAS (pH 2.5) and AF-AB (pH 2.5) reactions, the cytoplasm displayed a red color. The cells contained membrane bounded secretory granules with very low electron density. The secretory pore of the Type C secretory cells was circular shape, and approximately 5.5 μm×5.5 μm. Cytoplasm was found to be homogeneous under H-E stain and Masson's trichrome stain, and displayed a red color. As the result of AB-PAS (pH 2.5) reaction, the cytoplasm displayed a red color. The electron density of the secretory substance was the highest among the three types of secretory cells. The ciliated cells had a ciliary tuft on the free surface and were distributed throughout the mantle with the exception of the adhesive organs. Neuroglial cells were connected to the basal membrane, epithelial cells, secretory cells and nerve fibers through cytoplasmic process, and contained neurosecretory granules with high electron density within the cytoplasm. PMID:24361231

  12. Electrogenic active proton pump in Rana esculenta skin and its role in sodium ion transport.

    PubMed Central

    Ehrenfeld, J; Garcia-Romeu, F; Harvey, B J

    1985-01-01

    Kinetic and electrophysiological studies were carried out in the in vitro Rana esculenta skin, bathed in dilute sodium solution, to characterize the proton pump and coupling between sodium absorption (JNa+n) and proton excretion (JH+n). JNa+n and JH+n were both dependent on transepithelial potential (psi ms); hyperpolarizing the skin decreased JNa+n and increased JH+n; depolarization produced the opposite effects. Amiloride (5 X 10(-5) M) at a clamped psi ms of +50 mV inhibited JNa+n without affecting JH+n. Variations of psi ms or pH had identical effects on JH+n. Ethoxzolamide inhibited JH+n and simultaneously increased psi ms by 15-30 mV. These changes were accompanied by depolarization of the apical membrane potential psi mc from -47 to -25 mV and an increase in apical membrane resistance of 30%; no significant effects on basolateral membrane potential (psi cs) and resistance (Rb) nor on shunt resistance (Rj) were observed. The proton pump appears to be localized at the apical membrane. The proton pump was also inhibited by deoxygenation, oligomycin, dicyclohexylcarbodiimide and vanadate (100, 78, 83 and 100% inhibition respectively). The variations of JH+n and of the measured electrical currents were significantly correlated. These findings are supportive evidence of a primary active proton pump, electrogenic and strictly linked to aerobic metabolism. The current-voltage (I-V) relation of the proton pump was obtained as the difference in the I-V curves of the apical membrane extracted before and after proton-pump inhibition by ethoxzolamide during amiloride block of sodium transport. The proton-pump current (IP) was best described by a saturable exponential function of psi mc. Maximal pump current (ImaxP) was calculated to be 200 nequiv h-1 cm-2 at a psi mc of +50 mV and the pump reversal potential ERP was -130 mV. The effect of ethoxzolamide to depolarize psi mc was dependent on the relation between psi mc and ERP. Maximal induced depolarization occurred at a psi mc of +50 mV whereas ethoxzolamide exerted minimal effect on psi mc when the ERP was approached either by voltage clamping the apical membrane or by the addition of amiloride. We show that electroneutral sodium-proton countertransport is not the mechanism of active proton excretion in frog skin but that it is the proton excretion which provides a favourable electrical driving force for passive apical sodium entry.(ABSTRACT TRUNCATED AT 400 WORDS) Images Fig. 6 Fig. 7 PMID:2582114

  13. The chemoreceptor surface of the taste disc in the frog, Rana esculenta. An ultrastructural study with lanthanum nitrate.

    PubMed

    Zancanaro, C; Sbarbati, A; Franceschini, F; Balercia, G; Osculati, F

    1990-09-01

    The distribution of lanthanum on the taste disc of the frog, Rana esculenta, after en bloc staining of the tongue with lanthanum nitrate was studied at the ultrastructural level by means of scanning electron microscopy (in the secondary electron mode or in the back scattered electron mode), energy-dispersive X-ray microanalysis, transmission electron microscopy and electron spectroscopic imaging. It was consistently found that lanthanum distribution on the surface of the taste disc is not homogeneous and that the surface of putative receptor cells is in contact with strongly lanthanum-positive material. Calcium co-localizes with lanthanum at that level. These results suggest that different microenvironments exist at the surface of the taste disc and that this could be relevant to the receptor function. PMID:2175737

  14. Itches-stimulating compounds from Colocasia esculenta (taro): bioactive-guided screening and LC-MS/MS identification.

    PubMed

    Yu, Jin-Gao; Liu, Pei; Duan, Jin-Ao; Tang, Zong-Xiang; Yang, Yan

    2015-10-15

    Colocasia esculenta (L.) Schoot (taro) is one of the most common crops in the world. Its rhizome was a tonic medicine and accustomed to treat some gastrointestinal disorders in traditional Chinese medicine. Today, the taro was further developed as anticancer prescription in herbal therapy. However, the mucilage of the fresh taro has irritation, and causes itchy feeling. The components in the mucilage were not evident up to now. Two active compounds, uracil and glycol-protein taro lectin (Accession number: A5HMM7), were purified and identified from the fresh taro. The glycol-protein taro lectin showed nerve stimulation activity on dorsal root ganglion (DRG) neurons from GCaMP transgenic mice at the concentration of 1mg/mL. PMID:26387442

  15. Phytoremediation potential of Cd and Zn by wetland plants, Colocasia esculenta L. Schott., Cyperus malaccensis Lam. and Typha angustifolia L. grown in hydroponics.

    PubMed

    Chayapan, P; Kruatrachue, M; Meetam, M; Pokethitiyook, P

    2015-09-01

    Cadmium and zinc phytoremediation potential of wetland plants, Colocasia esculenta, Cyperus malaccensis, and Typha angustifolia, was investigated. Plants were grown for 15 days in nutrient solutions containing various concentrations of Cd (0, 5, 10, 20, 50 mg l(-1)) and Zn (0, 10, 20, 50, 100 mg l(-1)). T angustifolia was tolerant to both metals as indicated by high RGR when grown in 50 mg I(-1) Cd and 100 mg I(-1) Zn solutions. All these plants accumulated more metals in their underground parts and > 100 mg kg(-1) in their aboveground with TF values < 1. Only C. esculenta could be considered a Zn hyperaccumulator because it could concentrate > 10,000 mg kg(-1) in its aboveground parts with TF > 1. T angustifolia exhibited highest biomass production and highest Cd and Zn uptake, confirming that this plant is a suitable candidate for treating of Cd contaminated soil/sediments. PMID:26521563

  16. Characterisation and evaluation of a novel feedstock, Manihot glaziovii, Muell. Arg, for production of bioenergy carriers: Bioethanol and biogas.

    PubMed

    Moshi, Anselm P; Crespo, Carla F; Badshah, Malik; Hosea, Ken M M; Mshandete, Anthony Manoni; Elisante, Emrode; Mattiasson, Bo

    2014-11-01

    The objective of this study was to characterise and evaluate a wild inedible cassava species, Manihot glaziovii as feedstock for bioenergy production. Tubers obtained from 3 different areas in Tanzania were characterised and evaluated for bioethanol and biogas production. These bioenergy carriers were produced both separately and sequentially and their energy values evaluated based on these two approaches. Composition analysis demonstrated that M. glaziovii is a suitable feedstock for both bioethanol and biogas production. Starch content ranged from 77% to 81%, structural carbohydrates 3-16%, total crude protein ranged from 2% to 8%. Yeast fermentation achieved ethanol concentration of up to 85g/L at a fermentation efficiency of 89%. The fuel energy of the bioethanol and methane from flour-peels mix ranged from 5 to 13 and 11 to 14MJ/kgVS, respectively. Co-production of bioethanol and biogas in which the peels were added to the fermentation residue prior to anaerobic digestion produced maximum fuel energy yield of (15-23MJ/kgVS). PMID:25237774

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

    PubMed Central

    Shen, Xin; Ma, Xiaoyin; Ren, Jianfeng; Zhao, Fangqing

    2009-01-01

    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 worm-like marine organisms with an uncertain phylogenetic position. In this report, we present the mitochondrial genome sequence of Phascolosoma esculenta, the first complete mitochondrial genome of the phylum. Results The mitochondrial genome of P.esculenta is 15,494 bp in length. The coding strand consists of 32.1% A, 21.5% C, 13.0% G, and 33.4% T bases (AT = 65.5%; AT skew = -0.019; GC skew = -0.248). It contains thirteen protein-coding genes (PCGs) with 3,709 codons in total, twenty-two transfer RNA genes, two ribosomal RNA genes and a non-coding AT-rich region (AT = 74.2%). All of the 37 identified genes are transcribed from the same DNA strand. Compared with the typical set of metazoan mt genomes, sipunculid lacks trnR but has an additional trnM. Maximum Likelihood and Bayesian analyses of the protein sequences show that Myzostomida, Sipuncula and Annelida (including echiurans and pogonophorans) form a monophyletic group, which supports a closer relationship between Sipuncula and Annelida than with Mollusca, Brachiopoda, and some other lophotrochozoan groups. Conclusion This is the first report of a complete mitochondrial genome as a representative within the phylum Sipuncula. It shares many more similar features with the four known annelid and one echiuran mtDNAs. Firstly, sipunculans and annelids share quite similar gene order in the mitochondrial genome, with all 37 genes located on the same strand; secondly, phylogenetic analyses based on the concatenated protein sequences also strongly support the sipunculan + annelid clade (including echiurans and pogonophorans). Hence annelid "key-characters" including segmentation may be more labile than previously assumed. PMID:19327168

  18. Comparative study of the methane production based on the chemical compositions of Mangifera Indica and Manihot Utilissima leaves.

    PubMed

    Mambanzulua Ngoma, Philippe; Hiligsmann, Serge; Sumbu Zola, Eric; Culot, Marc; Fievez, Thierry; Thonart, Philippe

    2015-01-01

    Leaves of Mangifera Indica (MI, mango leaves) and Manihot Utilissima (MU, cassava leaves) are available in tropical regions and are the most accessible vegetal wastes of Kinshasa, capital of Democratic Republic of Congo. These wastes are not suitably managed and are not rationally valorized. They are abandoned in full air, on the soil and in the rivers. They thus pollute environment. By contrast, they can be recuperated and treated in order to produce methane (energy source), organic fertilizer and clean up the environment simultaneously. The main objective of this study was to investigate methane production from MI and MU leaves by BMP tests at 30°C. The yields achieved from the anaerobic digestion of up to 61.3 g raw matter in 1 l medium were 0.001 l/g and 0.100 l CH4/g volatile solids of MI and MU leaves, respectively. The yield of MU leaves was in the range mentioned in the literature for other leaves because of a poor presence of bioactive substrates, and low C/N ratio. This methane yield corresponded to 7% of calorific power of wood. By contrast, the methane yield from MI leaves was almost nil suggesting some metabolism inhibition because of their rich composition in carbon and bioactive substrates. Whereas classical acidogenesis and acetogenesis were recorded. Therefore, methane production from the sole MI leaves seems unfavorable by comparison to MU leaves at the ambient temperature in tropical regions. Their solid and liquid residues obtained after anaerobic digestion would be efficient fertilizers. However, the methane productivity of both leaves could be improved by anaerobic co-digestion. PMID:25825684

  19. Nitrogen and phosphorus budget of a polyculture system of sea cucumber ( Apostichopus japonicus), jellyfish ( Rhopilema esculenta) and shrimp ( Fenneropenaeus chinensis)

    NASA Astrophysics Data System (ADS)

    Li, Junwei; Dong, Shuanglin; Gao, Qinfeng; Zhu, Changbo

    2014-06-01

    The nitrogen (N) and phosphorus (P) budget and the ecological efficiency of a polyculture system of sea cucumber ( Apostichopus japonicus), jellyfish ( Rhopilema esculenta) and shrimp ( Fenneropenaeus chinensis) were studied in a cofferdam, 120.2 ha in size. The nutrients were supplied by spring tide inflow. In total, 139600 kg N yr-1 and 9730 kg P yr-1 input to the system; while 118900 kg N yr-1 and 2840 kg P yr-1 outflowed from the system concurrently, thus the outflow was 85.7% (N) and 29.2% (P) of inflow. The production of N and P was 889.5 kg yr-1 and 49.28 kg yr-1 (sea cucumber) and 204 kg yr-1 and 18.03 kg yr-1 (jellyfish and shrimp), respectively. The utilization rate of N and P by polycultured animals was 7.8‰ and 6.9‰, respectively, 21.9% and 38% higher than that of monocultured sea cucumber. Our results indicated that the polyculture system was an efficient culture system of animals and a remediation system of coastal environment as well; it scavenged 14.3% and 70.8% of N and P, respectively. Such an ecological efficiency may be improved further by increasing either the stocking density or the size of sea cucumber or both.

  20. Granulopoiesis in tadpoles of Rana esculenta. Ultrastructural observations on the morphology and development of heterophil and basophil granules.

    PubMed Central

    Frank, G

    1989-01-01

    The morphology and development of heterophil and basophil granules from the trunk kidneys of Rana esculenta tadpoles were studied at the electron microscopic level. Cells of the heterophils series contain granules displaying either spheroid profiles with homogeneous content (Type A), or elongate profiles with a crystalloid interior (Type B). Type A granules apparently originate directly from Golgi-derived vesicles, which, gaining slightly in size and density, transform into the mature granules. Type B granules could be traced back to vacuolate structures showing an irregular content. Their development could be traced through increasingly elongated forms with the appearance of a characteristic crystalloid core. Fully developed basophil granules are considerably larger in size than heterophil granules and contain heterogeneous interna showing a central-cortical organisation: a finely stippled medullary zone of varying density is surrounded by a sickle-shaped and lamellate cortex (Type L), or a moderately dense and uniformly stippled medulla is enclosed by two diametrically opposed, cap-shaped, filamentous regions (Type F). The heterophil and basophil granules are compared to those in other vertebrates and possible phylogenetic aspects are discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:2606765

  1. Studies on the effect of the pyrethroid insecticide Decamethrin on ionic transport through the in vitro skin of Rana esculenta.

    PubMed

    Salibián, A

    1983-01-01

    The effect of the insecticide Decamethrin on ionic transport through the isolated skin of Rana esculenta was studied; the skins were bathed with 1-2 mEq Na2SO4 or choline-Cl solutions (exterior), and with Ringer normal (interior). Under open circuit (OC) conditions, mucosal Decamethrin (10(-6) M), did not provoke changes in Na+ fluxes. At 10(-5) M there was a slight inhibition of the JoNa+ after 30 min. The Cl- fluxes did not change. With longer treatments (60-90 min, OC, 10(-5) M) the JnNa+ was inhibited; at 10(-4) M it was augmented. The JnH+ was not affected. Serosal Decamethrin did not modify Na+ and H+ fluxes. In short circuit conditions, Decamethrin (10(-5) M) in the mucosal face inhibited the JnNa+; the JnH+ did not change in these conditions. The abscence of interaction of mucosal Decamethrin with Amiloride was shown. PMID:6139244

  2. In vitro starch digestibility, estimated glycemic index and antioxidant potential of taro (Colocasia esculenta L. Schott) corm.

    PubMed

    Simsek, Sebnem; Nehir El, Sedef

    2015-02-01

    The purpose of this study was to determine some functional properties of taro (Colocasia esculenta L. Schott) corm, which can be a good alternative to the other dietary carbohydrate sources with its high starch content. The total phenolic and flavonoid content of taro corm was found as 205±53mgCAE/100g and 61±9mgCAE/100g, respectively. The antioxidant capacity of corm was determined as 452±72mMTEAC/100g and 244±73mMTEAC/100g, by the scavenging activity against ABTS and DPPH radicals, respectively. The free glucose content of corms was less than 1%, whereas the 60% of dry matter was composed of starch. According to the results, the taro corms' starch was highly digestible and higher than the 50% of the starch was composed of rapidly digestible starch (RDS) fractions. The estimated glycemic index (eGI) of taro corm was 63.1±2.5, indicating taro corm as a medium GI food and a good dietary carbohydrate alternative especially for diabetic people. PMID:25172708

  3. Evaluation of hepatoprotective activity of Colocasia esculenta (L. Schott) leaves on thioacetamide-induced hepatotoxicity in rats.

    PubMed

    Chinonyelum, Azubike Nkiruka; Uwadiegwu, Achukwu Peter; Nwachukwu, Okwuosa Chukwugozie; Emmanuel, Oduah

    2015-11-01

    The hepatoprotective effect of orally administered leaf aqueous extract of Colocasia esculenta (CCLE) in thioacetamide-induced liver toxicity in rats was investigated in this study. Adult male Wistar rats (weight range: 120-150g) were divided into 5 groups (n=5) and received no treatment (normal control), distilled water (negative control), 50mg/kg silymarin (positive control) and CCLE (250 and 500mg/kg) respectively once daily for 3 consecutive days. Thioacetamide (TAA) (150mg/kg b.w.) was administered intraperitoneally on the 4th day to rats in all groups except the normal control. Evaluations were made for serum levels of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphate (ALP) and serum albumin. Histopathological examination was performed on the excised liver tissues. TAA-induced hepatotoxicity increased ALT, AST, ALP and decreased serum albumin. Histopathological results revealed extensive disruption of the liver histoarchitecture when compared to the normal control liver sections. Pre-treatment with CCLE showed protective effects by normalizing the liver enzymes markers. These results were supported by the histopathological observations. The activity of the CCLE was comparable to that of the standard hepatoprotective drug, silymarin (50mg/kg). Overall findings suggest that CCLE possesses in vivo hepatoprotective activity against thioacetamide in rats. PMID:26687753

  4. Evaluation of Rana snk esculenta blood cell response to chemical stressors in the environment during the larval and adult phases.

    PubMed

    Barni, Sergio; Boncompagni, Eleonora; Grosso, Amelia; Bertone, Vittorio; Freitas, Isabel; Fasola, Mauro; Fenoglio, Carla

    2007-02-15

    The assessment of the biological effects on aquatic vertebrate species is frequently employed to monitor water pollution, as it provides significant information on bioavailability and actual concentration levels. In anamniote vertebrates (fish and amphibians), significant correlations have been observed between exposure to contaminants - both natural and experimental - and blood modification. We investigated the changes in some circulating blood cell parameters of green frog (Rana snk esculenta) tadpoles and adults collected at two sample rice fields, one heavily polluted and the other relatively unpolluted. The frequency of eosinophilic leucocytes, mitotic, anucleated and micronucleated erythrocytes was evaluated also regarding the haemopoietic/haemocatheretic and NOS expression of the liver. Haematological indicators in polluted samples were found to be significantly different from controls as regards both larval and adult exposure, and provided information on long-term background pollution of the habitats under investigation. The population of the polluted area showed evident effects of chronic exposure to contaminants, to a degree which could lead to sub-lethal alterations of their health status. The general nature of responses to this kind of stress emphasizes the role of amphibian peripheral blood as a sensitive indicator regarding contamination in aquatic environments. PMID:17150265

  5. Involvement of tyrosine kinase and cAMP in growth hormone-induced vitellogenin synthesis in the anuran, Rana esculenta.

    PubMed

    Carnevali, O; Mosconi, G; Polzonetti-Magni, A M

    2000-08-11

    In the frog Rana esculenta, a multihormonal control of vitellogenin synthesis was previously demonstrated. Now in this study, the identity of intracellular second messengers that mediate the GH effects on hepatic VTG synthesis are described. The results clearly indicate that the effect of GH on frog hepatocytes, in vitro, works through a local production of IGF I; in fact, IGF I affects VTG synthesis and its action occurs faster with respect to that of GH. The effect of IGF I was abolished by the anti-estrogen tamoxifen, indicating the involvement of estrogen receptor in VTG induction by IGF I. Furthermore, in vitro treatment of frog hepatocytes with GH resulted in an increase of cAMP with maximum levels after 20 min of treatment. Besides the increase of cAMP, GH induced the appearance of a new phosphotyrosine protein at 20 min, suggesting the occurrence of tyrosine kinase activation. Addition of adenylate cyclase or protein tyrosine kinase inhibitors completely abolished the induction of VTG synthesis, indicating the involvement of cAMP and of a phosphotyrosine protein in VTG synthesis stimulated by both GH and IGF I. PMID:10983843

  6. TiO2 immobilized on Manihot carbon: optimal preparation and evaluation of its activity in the decomposition of indigo carmine.

    PubMed

    Antonio-Cisneros, Cynthia M; Dávila-Jiménez, Martín M; Elizalde-González, María P; García-Díaz, Esmeralda

    2015-01-01

    Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture. PMID:25588214

  7. TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine

    PubMed Central

    Antonio-Cisneros, Cynthia M.; Dávila-Jiménez, Martín M.; Elizalde-González, María P.; García-Díaz, Esmeralda

    2015-01-01

    Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture. PMID:25588214

  8. Structural analysis and binding properties of isoforms of tarin, the GNA-related lectin from Colocasia esculenta.

    PubMed

    Pereira, Patrícia R; Winter, Harry C; Verícimo, Mauricio A; Meagher, Jennifer L; Stuckey, Jeanne A; Goldstein, Irwin J; Paschoalin, Vânia M F; Silva, Joab T

    2015-01-01

    The lectins, a class of proteins that occur widely in animals, plants, fungi, lichens and microorganisms, are known for their ability to specifically bind to carbohydrates. Plant lectins can be classified into 12 families including the Galanthus nivalis agglutinin (GNA)-related lectin superfamily, which is widespread among monocotyledonous plants and binds specifically to mannose, a behavior that confers remarkable anti-tumor, anti-viral and insecticidal properties on these proteins. The present study characterized a mitogenic lectin from this family, called tarin, which was purified from the crude extract from taro (Colocasia esculenta). The results showed that tarin is a glycoprotein with 2-3% carbohydrate content, composed of least 10 isoforms with pIs ranging from 5.5 to 9.5. The intact protein is a heterotetramer of 47kDa composed of two non-identical and non-covalently associated polypeptides, with small subunits of 11.9kDa and large subunits of 12.6kDa. The tarin structure is stable and recovers or maintains its functional structure following treatments at different temperatures and pH. Tarin showed a complex carbohydrate specificity, binding with high affinity to high-mannose and complex N-glycans. Many of these ligands can be found in viruses, tumor cells and insects, as well as in hematopoietic progenitor cells. Chemical modifications confirmed that both conserved and non-conserved amino acids participate in this interaction. This study determined the structural and ligand binding characteristics of a GNA-related lectin that can be exploited for several different purposes, particularly as a proliferative therapeutic molecule that is able to enhance the immunological response. PMID:25448725

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

    PubMed Central

    Mahmud, ZA; Bachar, SC; Qais, N

    2012-01-01

    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

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

    PubMed

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

    2011-10-01

    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

  11. Binding of insecticidal lectin Colocasia esculenta tuber agglutinin (CEA) to midgut receptors of Bemisia tabaci and Lipaphis erysimi provides clues to its insecticidal potential.

    PubMed

    Roy, Amit; Gupta, Sumanti; Hess, Daniel; Das, Kali Pada; Das, Sampa

    2014-07-01

    The insecticidal potential of Galanthus nivalis agglutinin-related lectins against hemipterans has been experimentally proven. However, the basis behind the toxicity of these lectins against hemipterans remains elusive. The present study elucidates the molecular basis behind insecticidal efficacy of Colocasia esculenta tuber agglutinin (CEA) against Bemisia tabaci and Lipaphis erysimi. Confocal microscopic analyses highlighted the binding of 25 kDa stable homodimeric lectin to insect midgut. Ligand blots followed by LC MS/MS analyses identified binding partners of CEA as vacuolar ATP synthase and sarcoplasmic endoplasmic reticulum type Ca(2+) ATPase from B. tabaci, and ATP synthase, heat shock protein 70 and clathrin heavy chain assembly protein from L. erysimi. Internalization of CEA into hemolymph was confirmed by Western blotting. Glycoprotein nature of the receptors was identified through glycospecific staining. Deglycosylation assay indicated the interaction of CEA with its receptors to be probably glycan mediated. Surface plasmon resonance analysis revealed the interaction kinetics between ATP synthase of B. tabaci with CEA. Pathway prediction study based on Drosophila homologs suggested the interaction of CEA with insect receptors that probably led to disruption of cellular processes causing growth retardation and loss of fecundity of target insects. Thus, the present findings strengthen our current understanding of the entomotoxic potentiality of CEA, which will facilitate its future biotechnological applications. PMID:24753494

  12. 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

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

    2011-05-01

    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. PMID:21325645

  13. 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

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

    2011-01-01

    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. PMID:21325645

  14. “Huay Bong 80” a new variety with high yield and high stability for starch content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huay Bong 80 is a new cassava (Manihot esculenta Crantz.) variety developed by researchers from Kasetsart University cooperating with the Thai Tapioca Development Institute (TTDI). This new variety has been protected by the Thai New Plant Variety Protection Act of B.E. 2542 (AD 1999) from January 4,...

  15. Molecular determination of the predator community of a cassava whitefly in Colombia: Pest-specific primer development and field validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In South America, the whitefly Aleurotrachelus socialis is one of the principal pests of cassava (Manihot esculenta Crantz), reaching high population levels throughout the Andean region. Management of this species is primarily based upon the use of insecticides, while biological control has received...

  16. BEMISIA TABACI (HOMOPTERA: ALEYRODIDAE) BIOTYPES IN INDIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host plant performance, esterase, and virus transmission tests revealed cassava-strain and sweetpotato-strain populations of whitefly Bemisia tabaci (Gennadius) biotypes in India. Individuals from the sweetpotato-reared population did not breed on cassava, Manihot esculenta Crantz, and the cassava-s...

  17. The BioCassava Plus program: Biofortification of cassava for sub-Saharan Africa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 BioCassav...

  18. Genetic mapping using genotyping-by-sequencing in the clonally-propagated cassava

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cassava (Manihot esculenta L.) is one of the most important food crops in the tropics, but yields are far below their potential. The gene-pool of cassava contains natural genetic diversity relevant to many important breeding goals, but breeding progress has been slow, partly due to insufficient geno...

  19. Taro (Colocasia esculenta (L.) Schott).

    PubMed

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

    2015-01-01

    Genetic engineering of taro is an effective method to improve taro quality and the resistance to various diseases of taro. Agrobacterium tumefaciens-mediated transformation of taro is more efficient than the particle bombardment transformation method based on current research. The development of a regeneration system starting from taro shoot tip explants could produce dasheen mosaic virus (DsMV)-free plantlets. Highly regenerative calluses could be developed from DsMV-free, in vitro plantlets on the Murashige and Skoog (MS) medium with 2 mg/L BA and 1 mg/L NAA (M5 medium). The Agrobacterium tumefaciens-mediated transformation method is reported in this chapter. The highly regenerative calluses were selected and cocultivated with the Agrobacterium strain EHA105 harboring the binary vector PBI121 with either a rice chitinase gene chi11 or a wheat oxalate oxidase gene gf2.8. After cocultivation for 3-4 days, these calluses were transferred to selection medium (M5 medium) containing 50 mg/L Geneticin G418 and grown for 3 months in the dark. Transgenic shoot lines could be induced and selected on the MS medium containing 4 mg/L BA (M15 medium) and 50 mg/L Geneticin G418 for 3 months further in the light. Molecular analyses are used to confirm the stable transformation and expression of the disease resistance gene chi11 or gf2.8. Pathologic bioassays could be used to demonstrate whether the transgenic plants had increased disease resistance to taro pathogens Sclerotium rolfsii or Phytophthora colocasiae. PMID:25416252

  20. Effect of boiling time on chemical composition and physico-functional properties of flours from taro (Colocasia esculenta cv fouê) corm grown in Côte d'Ivoire.

    PubMed

    Amon, Anon Simplice; Soro, René Yadé; Assemand, Emma Fernande; Dué, Edmond Ahipo; Kouamé, Lucien Patrice

    2014-05-01

    Taro (Colocasia esculenta cv fouê) corm was subjected to different boiling times and the changes in chemical composition and physico-functional properties were investigated using standard method. The change in boiling time led to a significant (P < 0.05) reduction in the moisture, reducing sugars, total sugars, crude fat, crude fibre, total phenolic compound contents and iodine affinity of starch, whereas the total carbohydrate content, water absorption capacity, water solubility index, paste clarity and foam capacity increased significantly (p < 0.05). The crude protein and total ash contents of the flours from taro corm were not affected significantly (p < 0.05) by the change in boiling time. Taro corm flours exhibited highest total carbohydrate, crude fibre, total ash contents, water absorption capacity, iodine affinity of starch and lowest crude protein and fat contents, foaming capacity and water solubility index. Principal component analysis showed that flours from taro corm boiled during 20 min and 15 min were located at the left of the score plot, while flours from raw and boiled taro corm during 10 min had a large positive score in the first principal component. PMID:24803691

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

    PubMed

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

    2009-08-11

    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

  2. Optical chemosensor for the detection of cyanide in water based on ethyl(hydroxyethyl)cellulose functionalized with Brooker's merocyanine.

    PubMed

    Nandi, Leandro G; Nicoleti, Celso R; Bellettini, Ismael C; Machado, Vanderlei G

    2014-05-20

    Ethyl(hydroxyethyl)cellulose was functionalized with Brooker's merocyanine. The modified polymer was easily transformed in a film, which could be used as a highly selective chromogenic and fluorogenic chemosensor for the detection of cyanide in water, with detection limits of 1.9 × 10(-5) and 1.0 × 10(-7) mol L(-1). The film was successfully applied to the detection of cyanide in cassava (Manihot esculenta Crantz) roots, which are a well-known source of endogenous biological cyanide. PMID:24805864

  3. Sequencing wild and cultivated cassava and related species reveals extensive interspecific hybridization and genetic diversity.

    PubMed

    Bredeson, Jessen V; Lyons, Jessica B; Prochnik, Simon E; Wu, G Albert; Ha, Cindy M; Edsinger-Gonzales, Eric; Grimwood, Jane; Schmutz, Jeremy; Rabbi, Ismail Y; Egesi, Chiedozie; Nauluvula, Poasa; Lebot, Vincent; Ndunguru, Joseph; Mkamilo, Geoffrey; Bart, Rebecca S; Setter, Tim L; Gleadow, Roslyn M; Kulakow, Peter; Ferguson, Morag E; Rounsley, Steve; Rokhsar, Daniel S

    2016-05-01

    Cassava (Manihot esculenta) provides calories and nutrition for more than half a billion people. It was domesticated by native Amazonian peoples through cultivation of the wild progenitor M. esculenta ssp. flabellifolia and is now grown in tropical regions worldwide. Here we provide a high-quality genome assembly for cassava with improved contiguity, linkage, and completeness; almost 97% of genes are anchored to chromosomes. We find that paleotetraploidy in cassava is shared with the related rubber tree Hevea, providing a resource for comparative studies. We also sequence a global collection of 58 Manihot accessions, including cultivated and wild cassava accessions and related species such as Ceará or India rubber (M. glaziovii), and genotype 268 African cassava varieties. We find widespread interspecific admixture, and detect the genetic signature of past cassava breeding programs. As a clonally propagated crop, cassava is especially vulnerable to pathogens and abiotic stresses. This genomic resource will inform future genome-enabled breeding efforts to improve this staple crop. PMID:27088722

  4. Simultaneous saccharification and fermentation of cassava bagasse for L-(+)-lactic Acid production using Lactobacilli.

    PubMed

    John, Rojan P; Nampoothiri, K Madhavan; Pandey, Ashok

    2006-09-01

    Saccharification and fermentation of cassava (Manihot esculenta) bagasse was carried out in a single step for the production of L-(+)-lactic acid by Lactobacillus casei and Lactobacillus delbrueckii. Using 15.5% w/v of cassava bagasse as the raw material, a maximum starch to lactic acid conversion of 96% was obtained with L. casei with a productivity rate of 1.40 mg/mLxh and maximum yield of 83.8 mg/mL. It was 94% with L. delbrueckii with a productivity rate of 1.36 mg/mLxh and maximum yield of 81.9 mg/mL. Supplementation of bagasse with 0.01% w/v MnCl2 showed positive influence on the lactic acid production by L. casei. PMID:16960284

  5. Aspergillus 6V4, a Strain Isolated from Manipueira, Produces High Amylases Levels by Using Wheat Bran as a Substrate

    PubMed Central

    Celestino, Jessyca dos Reis; Duarte, Ana Caroline; Silva, Cláudia Maria de Melo; Sena, Hellen Holanda; Ferreira, Maria do Perpétuo Socorro Borges Carriço; Mallmann, Neila Hiraishi; Lima, Natacha Pinheiro Costa; Tavares, Chanderlei de Castro; de Souza, Rodrigo Otávio Silva; Souza, Érica Simplício; Souza, João Vicente Braga

    2014-01-01

    The aim of this study was screening fungi strains, isolated from manipueira (a liquid subproduct obtained from the flour production of Manihot esculenta), for amylases production and investigating production of these enzymes by the strain Aspergillus 6V4. The fungi isolated from manipueira belonged to Ascomycota phylum. The strain Aspergillus 6V4 was the best amylase producer in the screening assay of starch hydrolysis in petri dishes (ASHPD) and in the assay in submerged fermentation (ASbF). The strain Aspergillus 6V4 produced high amylase levels (335 UI/L) using wheat bran infusion as the exclusive substrate and the supplementation of this substrate with peptone decreased the production of this enzyme. The moisture content of 70% was the best condition for the production of Aspergillus 6V4 amylases (385 IU/g) in solid state fermentation (SSF). PMID:24724017

  6. Heterologous Expression of MeLEA3: A 10 kDa Late Embryogenesis Abundant Protein of Cassava, Confers Tolerance to Abiotic Stress in Escherichia coli with Recombinant Protein Showing In Vitro Chaperone Activity.

    PubMed

    Barros, Nicolle L F; da Silva, Diehgo T; Marques, Deyvid N; de Brito, Fabiano M; dos Reis, Savio P; de Souza, Claudia R B

    2015-01-01

    Late embryogenesis abundant (LEA) proteins are small molecular weight proteins involved in acquisition of tolerance to drought, salinity, high temperature, cold, and freezing stress in many plants. Previous studies revealed a cDNA sequence coding for a 10 kDa atypical LEA protein, named MeLEA3, predicted to be located into mitochondria with potential role in salt stress response of cassava (Manihot esculenta Crantz). Here we aimed to produce the recombinant MeLEA3 protein by heterologous expression in Escherichia coli and evaluate the tolerance of bacteria expressing this protein under abiotic stress. Our result revealed that the recombinant MeLEA3 protein conferred a protective function against heat and salt stress in bacterial cells. Also, the recombinant MeLEA3 protein showed in vitro chaperone activity by protection of NdeI restriction enzyme activity under heat stress. PMID:25990084

  7. Microbial control of the invasive spiraling whitefly on cassava with entomopathogenic fungi

    PubMed Central

    Boopathi, Thangavel; Karuppuchamy, Palaniappan; Singh, Soibam B.; Kalyanasundaram, Manickavasagam; Mohankumar, S.; Ravi, Madhaiyan

    2015-01-01

    Abstract The entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, Lecanicillium lecanii and Isaria fumosorosea were tested for their efficacy in managing the exotic spiraling whitefly Aleurodicus dispersus (Hemiptera, Aleyrodidae) on cassava (Manihot esculenta) during 2 seasons (2011-2012 and 2012-2013). The fungi I. fumosorosea and L. lecanii exhibited promising levels of control (> 70% mortality of the A. dispersus population). The percent mortality increased over time in both seasons. Application of I. fumosorosea was highly pathogenic to A. dispersus in both seasons compared to the other entomopathogenic fungi. Analysis of the percent mortality in both seasons revealed differences in efficacy between 3 and 15 days after treatment. The season also influenced the effects of the fungi on the A. dispersus population. Thus, entomopathogenic fungi have the potential to manage A. dispersus infestation of cassava. PMID:26691465

  8. Corrin-based chemosensors for the ASSURED detection of endogenous cyanide.

    PubMed

    Zelder, Felix; Tivana, Lucas

    2015-01-01

    Cassava (Manihot esculenta Crantz) is a staple food for more than 500 million people, especially in Africa and South America. However, its consumption bears risks as it contains cyanogenic glycosides that convert enzymatically to toxic cyanide during cell damage. To avoid serious health problems by unintentional cyanide intake, this dangerous product of decomposition must be removed before consumption. For monitoring such food processing procedures and for controlling the quality and safety of cassava products on the market, a convenient and reliable analytical method for routine applications without laboratory equipment is required. This Perspective summarizes the authors' work on corrin-based chemosensors for the ('naked-eye') detection of endogenous cyanide in cassava samples. Considering selectivity, sensitivity, handling and speed of detection, these systems are superior to currently applied methods. Based on these properties, the development of a test kit for application by rural farmers in remote locations is proposed. PMID:25317920

  9. An overview of protein identification studies in cassava.

    PubMed

    Batista de Souza, Cláudia R; dos Reis, Sávio P; Castelo Branco Carvalho, Luiz J

    2015-01-01

    Cassava (Manihot esculenta Crantz) belongs to the Euphorbiaceae family and is originated from the Southern Amazon basin. The storage root is the most important product of cassava as food for more than 800 million people in Africa, Asia and Latin America. In this review, we present a retrospective of studies aiming the identification of cassava proteins, starting from the first investigations using SDS-PAGE and classical two-dimensional gel electrophoresis (2DE) to recent studies with advanced technologies such as high-resolution 2DE, mass spectrometry, and iTRAQ-based analysis that have contributed for characterization of cassava proteome. Several cassava proteins have been identified, including those involved in the storage root formation and post-harvest physiological deterioration processes. PMID:25707473

  10. Cassava brown streak disease: a threat to food security in Africa.

    PubMed

    Patil, Basavaprabhu L; Legg, James P; Kanju, Edward; Fauquet, Claude M

    2015-05-01

    Cassava brown streak disease (CBSD) has emerged as the most important viral disease of cassava (Manihot esculenta) in Africa and is a major threat to food security. CBSD is caused by two distinct species of ipomoviruses, Cassava brown streak virus and Ugandan cassava brown streak virus, belonging to the family Potyviridae. Previously, CBSD was reported only from the coastal lowlands of East Africa, but recently it has begun to spread as an epidemic throughout the Great Lakes region of East and Central Africa. This new spread represents a major threat to the cassava-growing regions of West Africa. CBSD-resistant cassava cultivars are being developed through breeding, and transgenic RNA interference-derived field resistance to CBSD has also been demonstrated. This review aims to provide a summary of the most important studies on the aetiology, epidemiology and control of CBSD and to highlight key research areas that need prioritization. PMID:26015320

  11. Microbial control of the invasive spiraling whitefly on cassava with entomopathogenic fungi.

    PubMed

    Boopathi, Thangavel; Karuppuchamy, Palaniappan; Singh, Soibam B; Kalyanasundaram, Manickavasagam; Mohankumar, S; Ravi, Madhaiyan

    2015-01-01

    The entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, Lecanicillium lecanii and Isaria fumosorosea were tested for their efficacy in managing the exotic spiraling whitefly Aleurodicus dispersus (Hemiptera, Aleyrodidae) on cassava (Manihot esculenta) during 2 seasons (2011-2012 and 2012-2013). The fungi I. fumosorosea and L. lecanii exhibited promising levels of control (> 70% mortality of the A. dispersus population). The percent mortality increased over time in both seasons. Application of I. fumosorosea was highly pathogenic to A. dispersus in both seasons compared to the other entomopathogenic fungi. Analysis of the percent mortality in both seasons revealed differences in efficacy between 3 and 15 days after treatment. The season also influenced the effects of the fungi on the A. dispersus population. Thus, entomopathogenic fungi have the potential to manage A. dispersus infestation of cassava. PMID:26691465

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

    PubMed

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

    2010-12-01

    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

  13. Unexpected Outcomes of Thai Cassava Trade: A Case of Global Complexity and Local Unsustainability

    PubMed Central

    CURRAN, SARA R.; COOKE, ABIGAIL M.

    2014-01-01

    Tracing the Thai cassava (Manihot esculenta) trade network, between 1960 and 2000, offers a compelling example of global complexity at work. The emergence of Thailand’s dominance of world export markets caught the world by surprise. The opening up of a European market for cassava was supposed to be met by Brazilian and Indonesian producers. Instead, Thailand took over the market by 1975. Several factors facilitated this emergence including: entrepreneurial diasporic networks of Thai-Chinese traders, local political economy conditions in both Europe and Thailand, and ecological conditions in Thailand. These same factors also shaped the subsequent timing of the closing of the European market, the emergence of a new industry association, the creation of new cassava products, and the expansion to other markets. Furthermore, the dynamic nature of cassava market yielded equivocal outcomes for both Europe and Thai farmers. PMID:25328444

  14. PLANT POISONING IN THAILAND: A 10-YEAR ANALYSIS FROM RAMATHIBODI POISON CENTER.

    PubMed

    Sriapha, Charuwan; Tongpoo, Achara; Wongvisavakorn, Sunun; Rittilert, Panee; Trakulsrichai, Satariya; Srisuma, Sahaphume; Wananukul, Winai

    2015-11-01

    Plant poisoning is not uncommon in Thailand. The objective of this study was to determine the incidence, type, clinical manifestations, severity and outcomes of plant poisoned patients in Thailand over a 10-year period. We retrospectively reviewed data from the Ramathibodi Poison Center Toxic Exposure Surveillance System for 2001-2010. A total of 2,901 poisonous plant exposure cases were identified, comprising 3.1% of the 92,392 poison cases recorded during the study period. This was the fifth most common type of poisoning recorded. Children aged < 13 years comprised the largest percent (69.8%) of the cases. The major type of exposure was unintentional ingestion. Ninety-nine types of poisonous plants were recorded as the causative agents among 99.1%of the cases. Gastrointestinal symptoms were reported in 72.0% of cases with Jatropha curcas (physic nut) comprising 54.1% of these. Most patients had only minor signs and symptoms. The mortality rate among the total plant poisoning cases was 0.9%, with 26 deaths. Thirteen deaths occurred in children aged < 13 years. The greatest number of fatalities were due to ingestion of Manihot esculenta (cassava), primarily due to multi-system organ failure. Children aged < 13 years are at the greatest risk for plant poisoning in Thailand; mostly unintentional. Most cases were minor and the mortality rate was low. Jatropha curcas was the most common cause of poisoning and Manihot esculenta was the most common cause of death. Public education is important to minimize these poisonings. PMID:26867365

  15. Development of cassava periclinal chimera may boost production.

    PubMed

    Bomfim, N; Nassar, N M A

    2014-01-01

    Plant periclinal chimeras are genotypic mosaics arranged concentrically. Trials to produce them to combine different species have been done, but pratical results have not been achieved. We report for the second time the development of a very productive interspecific periclinal chimera in cassava. It has very large edible roots up to 14 kg per plant at one year old compared to 2-3 kg in common varieties. The epidermal tissue formed was from Manihot esculenta cultivar UnB 032, and the subepidermal and internal tissue from the wild species, Manihot fortalezensis. We determined the origin of tissues by meiotic and mitotic chromosome counts, plant anatomy and morphology. Epidermal features displayed useful traits to deduce tissue origin: cell shape and size, trichome density and stomatal length. Chimera roots had a wholly tuberous and edible constitution with smaller starch granule size and similar distribution compared to cassava. Root size enlargement might have been due to an epigenetic effect. These results suggest a new line of improved crop based on the development of interspecific chimeras composed of different combinations of wild and cultivated species. It promises boosting cassava production through exceptional root enlargement. PMID:24615046

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

    NASA Astrophysics Data System (ADS)

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

    2008-09-01

    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.

  17. Production of endolymph in the semicircular canal of the frog Rana esculenta.

    PubMed Central

    Bernard, C; Ferrary, E; Sterkers, O

    1986-01-01

    The mechanisms of secretion of endolymph were studied in vitro in the isolated inner ear of the frog. Prior to in vitro experiments, the composition of perilymph was evaluated in vivo and compared to that of plasma. Composition of perilymph resembled that of an extracellular fluid, although Na and Cl concentrations were higher and K concentration was lower in perilymph than in plasma water. No difference in Ca and Mg concentrations was observed between these two fluids. Osmolality averaged 227 mosmol/kg H2O in perilymph and 183 mosmol/kg H2O in plasma. Endolymph in frog inner ear corresponded in chemical pattern to mammalian endolymph. K and Na concentrations in endolymph collected from the ampulla of the posterior vertical semicircular canal averaged 121.1 mM and 2.5 mM, respectively. Osmolality of endolymph was 237 mosmol/kg H2O. K and Na concentrations were unaltered when inner ears were incubated for 24 h either at 15 degrees C or at 4 degrees C. Addition of ouabain (10(-4) M) to the perilymph-like bathing solution altered greatly Na and K composition of endolymph after incubation for 3 h at 15 degrees C. The Na and K concentration gradients between endolymph and the bath were abolished after incubation for 24 h. Ligatures of the posterior vertical semicircular canal were performed at different sites to isolate some parts of the canal, i.e. the ampulla and the non-ampullar duct. K concentration in the ampulla after incubation for 24 h remained as high as 20 times that in the bath. This K gradient was abolished in the presence of ouabain (10(-4) M). High K concentration could be maintained in the non-ampullar part of the semicircular canal only if the latter communicated with the ampulla. It is concluded that endolymph is actively secreted into the ampulla of the semicircular canal. Na+-K+-activated ATPase in the ampullar dark cells may energize the ouabain sensitive ionic transports that are involved in the production of endolymph. Endolymph secreted into the ampulla would spread intraluminally to account for the high K and low Na concentrations of the fluid which fills the non-secretory part of the semicircular canal. Images Fig. 1 PMID:3486270

  18. Coupling between chloride absorption and base excretion in isolated skin of Rana esculenta.

    PubMed

    Ehrenfeld, J; Garcia-Romeu, F

    1978-07-01

    The net excretory fluxes of base (HCO3- or OH-) and the unidirectional fluxes of chloride were measured and their relationship examined in isolated frog skin maintained in open- or short-circuit (OC and SC) conditions. When the mucosal solution was a 2 mM choline chloride solution and the serosal solution a Ringer solution buffered with a HCO3-/CO2 mixture, the rate of base excretion was -105 +/- 10 in OC and -60 +/- 7 neq h-1 cm-2 in SC. A highly significant correlation was observed between the influx of chloride and the excretion of base. As a function of external chloride both these parameters followed saturation kinetics, Vmax being obtained for a chloride concentration below 2 mM. The removal of chloride in the external solution was followed by a 70 or 100% inhibition of base excretion in OC and SC conditions, respectively. Chloride transport is dependent on the presence of a HCO3-/CO2 mixture in the internal or the external medium. This transport, as well as base excretion, is inhibited to a considerable extent by removal of HCO3-/CO2 or by acetazolamide (10(-3) M). This investigation characterizes a saturable transport system in which chloride absorption and base excretion are coupled. PMID:307916

  19. Dissipation of flubendiamide in/on okra [Abelmoschus esculenta (L.) Moench] fruits.

    PubMed

    Das, Shaon Kumar; Mukherjee, Irani; Das, Suvo Kumar

    2012-03-01

    A field experiment was undertaken at Indian Agricultural Research Institute, New Delhi during kharif (rainy season) in the year 2010 to evaluate the residue persistence of flubendiamide in/on okra fruits following foliar application of Belt 39.35% SC formulation at 24 (standard dose) and 48 (double dose) g a.i. ha(-1). After HPLC analysis study revealed that residues of flubendiamide in/on okra persisted till 5th and 7th day after the last spray at standard and double dose, respectively. The residues of flubendiamide were reported as parent compound, and des-iodo flubendiamide, a metabolite (photo product) of flubendiamide, was not detected in/on okra at any time during the study period. The initial deposits of 0.28 and 0.53 μg g(-1) in/on okra fruits reached below determination level of 0.01 μg g(-1) on the 7th and 10th day at standard and double dose, respectively. The half life of flubendiamide in/on okra fruits ranged from 4.7 to 5.1 days at standard and double dose, respectively. Soil sample collected from the treated field on the 15th day after the last spray revealed residues of flubendiamide or its metabolite below determination level (0.01 μg g(-1)) at single and double dose. PMID:22147083

  20. Polyphenol content and modulatory activities of some tropical dietary plant extracts on the oxidant activities of neutrophils and myeloperoxidase.

    PubMed

    Tsumbu, Cesar N; Deby-Dupont, Ginette; Tits, Monique; Angenot, Luc; Frederich, Michel; Kohnen, Stephane; Mouithys-Mickalad, Ange; Serteyn, Didier; Franck, Thierry

    2012-01-01

    Young leaves of Manihot esculenta Crantz (Euphorbiaceae), Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae) and Pteridium aquilinum (Dennstaedtiaceae) are currently consumed as green vegetables by peoples in sub-Saharan Africa, Latin America, Asia and their migrants living in Western Europe. Sub-Saharan peoples use Manihot, Abelmoschus and Hibiscus also in the folk medicine to alleviate fever and pain, in the treatment of conjunctivitis, rheumatism, hemorrhoid, abscesses, ... The present study investigates the effects of aqueous extracts of those plants on the production of reactive oxygen species (ROS) and the release of myeloperoxidase (MPO) by equine neutrophils activated with phorbol 12-myristate 13-acetate (PMA). The ROS production was measured by lucigenin-enhanced chemiluminescence (CL), and the release of total MPO by an ELISA method. The study also investigates the effect of the extracts on the activity of MPO by studying its nitration activity on tyrosine and by using a new technique called SIEFED (Specific Immunological Extraction Followed by Enzymatic Detection) that allows studying the direct interaction of compounds with the enzyme. In all experiments, the aqueous extracts of the plants developed concentration-dependent inhibitory effects. A moderate heat treatment did not significantly modify the inhibitory capacity of the extracts in comparison to not heated ones. Total polyphenol and flavonoid contents were determined with an HPLC-UV/DAD analysis and a spectroscopic method using Folin-Ciocalteu reagent. Some polyphenols with well-known antioxidant activities (caffeic acid, chlorogenic acid, hyperoside, rosmarinic acid and rutin) were found in the extracts and may partly explain the inhibitory activities observed. The role of those dietary and medicinal plants in the treatment of ROS-dependent inflammatory diseases could have new considerations for health. PMID:22312276

  1. Endophytic fungi from the Amazonian plant Paullinia cupana and from Olea europaea isolated using cassava as an alternative starch media source.

    PubMed

    Sia, Eliandra de Freitas; Marcon, Joelma; Luvizotto, Danice Mazzer; Quecine, Maria Carolina; Tsui, Sarina; Pereira, José Odair; Pizzirani-Kleiner, Aline Aparecida; Azevedo, João Lúcio

    2013-01-01

    Endophytic fungi live inside plants, apparently do not cause any harm to their hosts and may play important roles in defense and growth promotion. Fungal growth is a routine practice at microbiological laboratories, and the Potato Dextrose Agar (PDA) is the most frequently used medium because it is a rich source of starch. However, the production of potatoes in some regions of the world can be costly. Aiming the development of a new medium source to tropical countries, in the present study, we used leaves from the guarana (a tropical plant from the Amazon region) and the olive (which grows in subtropical and temperate regions) to isolate endophytic fungi using PDA and Manihot Dextrose Agar (MDA). Cassava (Manihot esculenta) was evaluated as a substitute starch source. For guarana, the endophytic incidence (EI) was 90% and 98% on PDA and MDA media, respectively, and 65% and 70% for olive, respectively. The fungal isolates were sequenced using the ITS- rDNA region. The fungal identification demonstrated that the isolates varied according to the host plant and media source. In the guarana plant, 13 fungal genera were found using MDA and six were found using PDA. In the olive plant, six genera were obtained using PDA and 4 were obtained using MDA. The multivariate analysis results demonstrated the highest fungal diversity from guarana when using MDA medium. Interestingly, some genera were isolated from one specific host or in one specific media, suggesting the importance of these two factors in fungal isolation specificity. Thus, this study indicated that cassava is a feasible starch source that could serve as a potential alternative medium to potato medium. PMID:25674409

  2. Local domestication of lactic acid bacteria via cassava beer fermentation

    PubMed Central

    Meadow, James F.; Liebert, Melissa A.; Cepon-Robins, Tara J.; Gildner, Theresa E.; Urlacher, Samuel S.; Bohannan, Brendan J.M.; Snodgrass, J. Josh; Sugiyama, Lawrence S.

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal. PMID:25071997

  3. Recent advances in cassava pest management.

    PubMed

    Bellotti, A C; Smith, L; Lapointe, S L

    1999-01-01

    Cassava (Manihot esculenta) occupies a uniquely important position as a food security crop for smallholder farmers in ares of the tropics where climate, soils, or societal stresses constrain production. Given its reliability and productivity, cassava is the most important locally produced food in a third of the world's low-income, food-deficit countries. It is the fourth most important source of carbohydrates for human consumption in the tropics, after rice, sugar, and maize. World production of cassava from 1994-1996 averaged 166 million tons/year grown on 16.6 million hectares (ha), for an average yield of 9.9 tons/ha. Approximately 57% is used for human consumption, 32% for animal feed and industrial purposes, and 11% is waste. Africa accounts for 51.3% of the production; Asia, 29.4%; and Latin America, 19.3%. The area planted to cassava in Africa, Asia, and Latin America is 10.3, 3.7, and 2.6 million ha, respectively. PMID:9990720

  4. Digestible and metabolizable energy concentrations in copra meal, palm kernel meal, and cassava root fed to growing pigs.

    PubMed

    Son, A R; Ji, S Y; Kim, B G

    2012-12-01

    An experiment was conducted to measure DE and ME in copra (Cocos nucifera) meal (CM), palm kernel meal (PKM), and cassava (Manihot esculenta) root (CR) in growing pigs. Eight boars with an initial BW of 67.3 ± 5.8 kg were individually housed in metabolism crates that were equipped with a feeder and a nipple drinker. A replicated 4 × 4 Latin square design was used with 4 dietary treatments, 4 periods, and 8 animals. A basal diet mainly contained corn (Zea mays) and soybean (Glycine max) meal. Three additional diets were formulated to contain 30% of CM, PKM, and CR. All diets contained the same proportion of corn:soybean meal ratio at 4.14:1. The apparent total tract digestibility of energy was 89.5, 84.1, 82.4, and 87.9% (P < 0.001) in the basal, CM, PKM, and CR diets, respectively. The DE in CM and PKM were greater (P < 0.05) than in CR (3440 and 3238 vs. 2966 kcal/kg as-fed). The ME in CM was greater (P < 0.05) than in CR (3340 vs. 2935 kcal/kg as-fed) but not different from the ME in PKM (3168 kcal/kg as-fed). In conclusion, CM and PKM have a higher DE value than CR, and CM has a higher ME value than CR. PMID:23365309

  5. Cyanogenesis in Cassava1

    PubMed Central

    White, Wanda L.B.; Arias-Garzon, Diana I.; McMahon, Jennifer M.; Sayre, Richard T.

    1998-01-01

    In the cyanogenic crop cassava (Manihot esculenta, Crantz), the final step in cyanide production is the conversion of acetone cyanohydrin, the deglycosylation product of linamarin, to cyanide plus acetone. This process occurs spontaneously at pH greater than 5.0 or enzymatically and is catalyzed by hydroxynitrile lyase (HNL). Recently, it has been demonstrated that acetone cyanohydrin is present in poorly processed cassava root food products. Since it has generally been assumed that HNL is present in all cassava tissues, we reinvestigated the enzymatic properties and tissue-specific distribution of HNL in cassava. We report the development of a rapid two-step purification protocol for cassava HNL, which yields an enzyme that is catalytically more efficient than previously reported (Hughes, J., Carvalho, F., and Hughes, M. [1994] Arch Biochem Biophys 311: 496–502). Analyses of the distribution of HNL activity and protein indicate that the accumulation of acetone cyanohydrin in roots is due to the absence of HNL, not to inhibition of the enzyme. Furthermore, the absence of HNL in roots and stems is associated with very low steady-state HNL transcript levels. It is proposed that the lack of HNL in cassava roots accounts for the high acetone cyanohydrin levels in poorly processed cassava food products. PMID:9536038

  6. Purification, Characterization, and Localization of Linamarase in Cassava 1

    PubMed Central

    Mkpong, Offiong E.; Yan, Hua; Chism, Grady; Sayre, Richard T.

    1990-01-01

    We have purified cassava (Manihot esculenta) linamarase to apparent homogeneity using a simplified extraction procedure using low pH phosphate buffer. Three isozymes of cassava linamarase were identified in leaves based on differences in isoelectric point. The enzyme is capable of hydrolyzing a number of β-glycosides in addition to linamarin. The enzyme is unusually stable and has a temperature optimum of 55°C. Immunogold labeling studies indicate that linamarase is localized in the cell walls of cassava leaf tissue. Since linamarin must cross the cell wall following synthesis in the leaf for transport to the root, it is likely that linamarin must cross the cell wall in a nonhydrolyzable form, possibly as the diglucoside, linustatin. In addition, we have quantified the levels of linamarin and linamarase activity in leaves of cassava varieties which differ in the linamarin content of their roots. We observed no substantial differences in the steady state linamarin content or linamarase activity of leaves from high or low (root) cyanogenic varieties. These results indicate that the steady state levels of linamarin and linamarase in leaves of high and low cyanogenic varieties are not correlated with the varietal differences in the steady state levels of linamarin in roots. Images Figure 1 Figure 2 Figure 3 PMID:16667431

  7. Effect of feeding cassava and/or Stylosanthes foliage on the performance of crossbred growing cattle.

    PubMed

    Thang, C M; Ledin, I; Bertilsson, J

    2010-01-01

    The effect of feeding different levels of cassava foliage (Manihot esculenta, Crantz) and/or Stylosanthes guianensis foliage on the growth and digestibility was studied using twenty eight 6-month-old crossbred growing cattle (50% local Yellow cattle and 50% Sindhi) (both Bos indicus) weighing on average 114 kg at start. All animals were fed a basal diet consisting of urea treated rice straw (URTRS) fed ad libitum, 0.87 kg concentrate and 0.22 kg molasses on dry matter (DM) basis. The treatments were four supplements: soybean meal, cassava foliage, stylosanthes foliage or a mix of stylosanthes foliage and cassava foliage all giving the same nitrogen intake. The consumption of tannins and hydrogen cyanide (HCN) were significantly higher in groups fed a mixture of foliages compared with only cassava foliage, respectively. There were 30% and 19%, respectively, higher live weight gain in the group fed a mixture of foliages as compared to the groups fed only cassava or stylosanthes. The factors of low organic matter and high level of HCN in the diet when feeding only cassava foliage might explain the negative effects on intake, neutral detergent fibre digestibility and nitrogen retention, and resulted in lower growth rates. PMID:19521793

  8. Augmenting iron accumulation in cassava by the beneficial soil bacterium Bacillus subtilis (GBO3)

    PubMed Central

    Freitas, Mônica A.; Medeiros, Flavio H. V.; Carvalho, Samuel P.; Guilherme, Luiz R. G.; Teixeira, William D.; Zhang, Huiming; Paré, Paul W.

    2015-01-01

    Cassava (Manihot esculenta), a major staple food in the developing world, provides a basic carbohydrate diet for over half a billion people living in the tropics. Despite the iron abundance in most soils, cassava provides insufficient iron for humans as the edible roots contain 3–12 times less iron than other traditional food crops such as wheat, maize, and rice. With the recent identification that the beneficial soil bacterium Bacillus subtilis (strain GB03) activates iron acquisition machinery to increase metal ion assimilation in Arabidopsis, the question arises as to whether this plant-growth promoting rhizobacterium also augments iron assimilation to increase endogenous iron levels in cassava. Biochemical analyses reveal that shoot-propagated cassava with GB03-inoculation exhibit elevated iron accumulation after 140 days of plant growth as determined by X-ray microanalysis and total foliar iron analysis. Growth promotion and increased photosynthetic efficiency were also observed for greenhouse-grown plants with GB03-exposure. These results demonstrate the potential of microbes to increase iron accumulation in an important agricultural crop and is consistent with idea that microbial signaling can regulate plant photosynthesis. PMID:26300897

  9. Improvement in the traditional processing method and nutritional quality of traditional extruded cassava-based snack (modified Ajogun)

    PubMed Central

    Obadina, Adewale O; Oyewole, Olusola B; Williams, Oluwasolabomi E

    2013-01-01

    This study was carried out to investigate and improve the traditional processing method and nutritional quality of the traditional cassava snack (Ajogun). Cassava root (Manihot esculenta Crantz L.) of TME 419 variety was processed into mash (40% moisture content). The cassava mash was mixed into different blends to produce fried traditional “Ajogun”, fried and baked extrudates (modified Ajogun) as snacks. These products were analyzed to determine the proximate composition including carbohydrate, fat, protein, fiber, ash, and moisture contents and functional properties such as bulk density. The results obtained for the moisture, fat, protein, and ash contents showed significant difference (P < 0.05) between the control sample and the extrudates. However, there was no significant difference (P > 0.05) in the carbohydrate and fiber contents between the three samples. There was no significant difference (P > 0.05) in the bulk density of the snacks. Also, sensory evaluation was carried out on the cassava-based snacks using the 9-point hedonic scale to determine the degree of acceptability. Results obtained showed significant difference (P < 0.05) between the extrudates and control sample in terms of appearance, taste, flavor, color, aroma, texture, and overall acceptability. The highest acceptability level of the product was at 8.04 for the control sample (traditional Ajogun). This study has shown that “Ajogun”, which is a lesser known cassava product, is rich in protein and fat. PMID:24804039

  10. Tuber Storage Proteins

    PubMed Central

    SHEWRY, PETER R.

    2003-01-01

    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

  11. Reactive oxygen species regulate leaf pulvinus abscission zone cell separation in response to water-deficit stress in cassava

    PubMed Central

    Liao, Wenbin; Wang, Gan; Li, Yayun; Wang, Bin; Zhang, Peng; Peng, Ming

    2016-01-01

    Cassava (Manihot esculenta Crantz) plant resists water-deficit stress by shedding leaves leading to adaptive water-deficit condition. Transcriptomic, physiological, cellular, molecular, metabolic, and transgenic methods were used to study the mechanism of cassava abscission zone (AZ) cell separation under water-deficit stress. Microscopic observation indicated that AZ cell separation initiated at the later stages during water-deficit stress. Transcriptome profiling of AZ suggested that differential expression genes of AZ under stress mainly participate in reactive oxygen species (ROS) pathway. The key genes involved in hydrogen peroxide biosynthesis and metabolism showed significantly higher expression levels in AZ than non-separating tissues adjacent to the AZ under stress. Significantly higher levels of hydrogen peroxide correlated with hydrogen peroxide biosynthesis related genes and AZ cell separation was detected by microscopic observation, colorimetric detection and GC-MS analyses under stress. Co-overexpression of the ROS-scavenging proteins SOD and CAT1 in cassava decreased the levels of hydrogen peroxide in AZ under water-deficit stress. The cell separation of the pulvinus AZ also delayed in co-overexpression of the ROS-scavenging proteins SOD and CAT1 plants both in vitro and at the plant level. Together, the results indicated that ROS play an important regulatory role in the process of cassava leaf abscission under water-deficit stress. PMID:26899473

  12. CG gene body DNA methylation changes and evolution of duplicated genes in cassava

    PubMed Central

    Wang, Haifeng; Beyene, Getu; Zhai, Jixian; Feng, Suhua; Fahlgren, Noah; Taylor, Nigel J.; Bart, Rebecca; Carrington, James C.; Jacobsen, Steven E.; Ausin, Israel

    2015-01-01

    DNA methylation is important for the regulation of gene expression and the silencing of transposons in plants. Here we present genome-wide methylation patterns at single-base pair resolution for cassava (Manihot esculenta, cultivar TME 7), a crop with a substantial impact in the agriculture of subtropical and tropical regions. On average, DNA methylation levels were higher in all three DNA sequence contexts (CG, CHG, and CHH, where H equals A, T, or C) than those of the most well-studied model plant Arabidopsis thaliana. As in other plants, DNA methylation was found both on transposons and in the transcribed regions (bodies) of many genes. Consistent with these patterns, at least one cassava gene copy of all of the known components of Arabidopsis DNA methylation pathways was identified. Methylation of LTR transposons (GYPSY and COPIA) was found to be unusually high compared with other types of transposons, suggesting that the control of the activity of these two types of transposons may be especially important. Analysis of duplicated gene pairs resulting from whole-genome duplication showed that gene body DNA methylation and gene expression levels have coevolved over short evolutionary time scales, reinforcing the positive relationship between gene body methylation and high levels of gene expression. Duplicated genes with the most divergent gene body methylation and expression patterns were found to have distinct biological functions and may have been under natural or human selection for cassava traits. PMID:26483493

  13. Improvement in the traditional processing method and nutritional quality of traditional extruded cassava-based snack (modified Ajogun).

    PubMed

    Obadina, Adewale O; Oyewole, Olusola B; Williams, Oluwasolabomi E

    2013-07-01

    This study was carried out to investigate and improve the traditional processing method and nutritional quality of the traditional cassava snack (Ajogun). Cassava root (Manihot esculenta Crantz L.) of TME 419 variety was processed into mash (40% moisture content). The cassava mash was mixed into different blends to produce fried traditional "Ajogun", fried and baked extrudates (modified Ajogun) as snacks. These products were analyzed to determine the proximate composition including carbohydrate, fat, protein, fiber, ash, and moisture contents and functional properties such as bulk density. The results obtained for the moisture, fat, protein, and ash contents showed significant difference (P < 0.05) between the control sample and the extrudates. However, there was no significant difference (P > 0.05) in the carbohydrate and fiber contents between the three samples. There was no significant difference (P > 0.05) in the bulk density of the snacks. Also, sensory evaluation was carried out on the cassava-based snacks using the 9-point hedonic scale to determine the degree of acceptability. Results obtained showed significant difference (P < 0.05) between the extrudates and control sample in terms of appearance, taste, flavor, color, aroma, texture, and overall acceptability. The highest acceptability level of the product was at 8.04 for the control sample (traditional Ajogun). This study has shown that "Ajogun", which is a lesser known cassava product, is rich in protein and fat. PMID:24804039

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

    PubMed

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

    2012-08-01

    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

  15. Local domestication of lactic acid bacteria via cassava beer fermentation.

    PubMed

    Colehour, Alese M; Meadow, James F; Liebert, Melissa A; Cepon-Robins, Tara J; Gildner, Theresa E; Urlacher, Samuel S; Bohannan, Brendan J M; Snodgrass, J Josh; Sugiyama, Lawrence S

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal. PMID:25071997

  16. LINE-1-like retrotransposons contribute to RNA-based gene duplication in dicots

    PubMed Central

    Zhu, Zhenglin; Tan, Shengjun; Zhang, Yaqiong; Zhang, Yong E.

    2016-01-01

    RNA-based duplicated genes or functional retrocopies (retrogenes) are known to drive phenotypic evolution. Retrogenes emerge via retroposition, which is mainly mediated by long interspersed nuclear element 1 (LINE-1 or L1) retrotransposons in mammals. By contrast, long terminal repeat (LTR) retrotransposons appear to be the major player in plants, although an L1-like mechanism has also been hypothesized to be involved in retroposition. We tested this hypothesis by searching for young retrocopies, as these still retain the sequence features associated with the underlying retroposition mechanism. Specifically, we identified polymorphic retrocopies (retroCNVs) by analyzing public Arabidopsis (Arabidopsis thaliana) resequencing data. Furthermore, we searched for recently originated retrocopies encoded by the reference genome of Arabidopsis and Manihot esculenta. Across these two datasets, we found cases with L1-like hallmarks, namely, the expected target site sequence, a polyA tail and target site duplications. Such data suggest that an L1-like mechanism could operate in plants, especially dicots. PMID:27098918

  17. Characters related to higher starch accumulation in cassava storage roots

    PubMed Central

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

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

    PubMed

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

    2007-02-27

    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

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

    PubMed

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

    2000-10-19

    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

  20. Data supporting the role of enzymes and polysaccharides during cassava postharvest physiological deterioration.

    PubMed

    Uarrota, Virgílio Gavicho; Moresco, Rodolfo; Schmidt, Eder Carlos; Bouzon, Zenilda Laurita; da Costa Nunes, Eduardo; de Oliveira Neubert, Enilto; Peruch, Luiz Augusto Martins; Rocha, Miguel; Maraschin, Marcelo

    2016-03-01

    This data article is referred to the research article entitled The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration by Uarrota et al. (2015). Food Chemistry 197, Part A, 737-746. The stress duo to PPD of cassava roots leads to the formation of ROS which are extremely harmful and accelerates cassava spoiling. To prevent or alleviate injuries from ROS, plants have evolved antioxidant systems that include non-enzymatic and enzymatic defence systems such as ascorbate peroxidase, guaiacol peroxidase and polysaccharides. In this data article can be found a dataset called "newdata", in RData format, with 60 observations and 06 variables. The first 02 variables (Samples and Cultivars) and the last 04, spectrophotometric data of ascorbate peroxidase, guaiacol peroxidase, tocopherol, total proteins and arcsined data of cassava PPD scoring. For further interpretation and analysis in R software, a report is also provided. Means of all variables and standard deviations are also provided in the Supplementary tables ("data.long3.RData, data.long4.RData and meansEnzymes.RData"), raw data of PPD scoring without transformation (PPDmeans.RData) and days of storage (days.RData) are also provided for data analysis reproducibility in R software. PMID:26900596

  1. Phytic acid in green leaves.

    PubMed

    Hadi Alkarawi, H; Zotz, G

    2014-07-01

    Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention. PMID:24341824

  2. Soil-to-root vegetable transfer factors for (226)Ra, (232)Th, (40)K, and (88)Y in Malaysia.

    PubMed

    Asaduzzaman, Kh; Khandaker, Mayeen Uddin; Amin, Y M; Bradley, D A; Mahat, R H; Nor, R M

    2014-09-01

    Soil-to-plant transfer factors (TFs) are of fundamental importance in assessing the environmental impact due to the presence of radioactivity in soil and agricultural crops. Tapioca and sweet potato, both root crops, are popular foodstuffs for a significant fraction of the Malaysian population, and result in intake of radionuclides. For the natural field conditions experienced in production of these foodstuffs, TFs and the annual effective dose were evaluated for the natural radionuclides (226)Ra, (232)Th, (40)K, and for the anthropogenic radionuclide (88)Y, the latter being a component of fallout. An experimental tapioca field was developed for study of the time dependence of plant uptake. For soil samples from all study locations other than the experimental field, it has been shown that these contain the artificial radionuclide (88)Y, although the uptake of (88)Y has only been observed in the roots of the plant Manihot esculenta (from which tapioca is derived) grown in mining soil. The estimated TFs for (226)Ra and (232)Th for tapioca and sweet potato are very much higher than that reported by the IAEA. For all study areas, the annual effective dose from ingestion of tapioca and sweet potato are estimated to be lower than the world average (290 μSv y(-1)). PMID:24814722

  3. Risk assessment of gene flow from genetically engineered virus resistant cassava to wild relatives in Africa: an expert panel report.

    PubMed

    Hokanson, Karen E; Ellstrand, Norman C; Dixon, Alfred G O; Kulembeka, Heneriko P; Olsen, Kenneth M; Raybould, Alan

    2016-02-01

    The probability and consequences of gene flow to wild relatives is typically considered in the environmental risk assessment of genetically engineered crops. This is a report from a discussion by a group of experts who used a problem formulation approach to consider existing information for risk assessment of gene flow from cassava (Manihot esculenta) genetically engineered for virus resistance to the 'wild' (naturalized) relative M. glaziovii in East Africa. Two environmental harms were considered in this case: (1) loss of genetic diversity in the germplasm pool, and (2) loss of valued species, ecosystem resources, or crop yield and quality due to weediness or invasiveness of wild relatives. Based on existing information, it was concluded that gene flow will occur, but it is not likely that this will reduce the genetic diversity in the germplasm pool. There is little existing information about the impact of the virus in natural populations that could be used to inform a prediction about whether virus resistance would lead to an increase in reproduction or survival, hence abundance of M. glaziovii. However, an increase in the abundance of M. glaziovii should be manageable, and would not necessarily lead to the identified environmental harms. PMID:26667472

  4. CG gene body DNA methylation changes and evolution of duplicated genes in cassava.

    PubMed

    Wang, Haifeng; Beyene, Getu; Zhai, Jixian; Feng, Suhua; Fahlgren, Noah; Taylor, Nigel J; Bart, Rebecca; Carrington, James C; Jacobsen, Steven E; Ausin, Israel

    2015-11-01

    DNA methylation is important for the regulation of gene expression and the silencing of transposons in plants. Here we present genome-wide methylation patterns at single-base pair resolution for cassava (Manihot esculenta, cultivar TME 7), a crop with a substantial impact in the agriculture of subtropical and tropical regions. On average, DNA methylation levels were higher in all three DNA sequence contexts (CG, CHG, and CHH, where H equals A, T, or C) than those of the most well-studied model plant Arabidopsis thaliana. As in other plants, DNA methylation was found both on transposons and in the transcribed regions (bodies) of many genes. Consistent with these patterns, at least one cassava gene copy of all of the known components of Arabidopsis DNA methylation pathways was identified. Methylation of LTR transposons (GYPSY and COPIA) was found to be unusually high compared with other types of transposons, suggesting that the control of the activity of these two types of transposons may be especially important. Analysis of duplicated gene pairs resulting from whole-genome duplication showed that gene body DNA methylation and gene expression levels have coevolved over short evolutionary time scales, reinforcing the positive relationship between gene body methylation and high levels of gene expression. Duplicated genes with the most divergent gene body methylation and expression patterns were found to have distinct biological functions and may have been under natural or human selection for cassava traits. PMID:26483493

  5. Reactive oxygen species regulate leaf pulvinus abscission zone cell separation in response to water-deficit stress in cassava.

    PubMed

    Liao, Wenbin; Wang, Gan; Li, Yayun; Wang, Bin; Zhang, Peng; Peng, Ming

    2016-01-01

    Cassava (Manihot esculenta Crantz) plant resists water-deficit stress by shedding leaves leading to adaptive water-deficit condition. Transcriptomic, physiological, cellular, molecular, metabolic, and transgenic methods were used to study the mechanism of cassava abscission zone (AZ) cell separation under water-deficit stress. Microscopic observation indicated that AZ cell separation initiated at the later stages during water-deficit stress. Transcriptome profiling of AZ suggested that differential expression genes of AZ under stress mainly participate in reactive oxygen species (ROS) pathway. The key genes involved in hydrogen peroxide biosynthesis and metabolism showed significantly higher expression levels in AZ than non-separating tissues adjacent to the AZ under stress. Significantly higher levels of hydrogen peroxide correlated with hydrogen peroxide biosynthesis related genes and AZ cell separation was detected by microscopic observation, colorimetric detection and GC-MS analyses under stress. Co-overexpression of the ROS-scavenging proteins SOD and CAT1 in cassava decreased the levels of hydrogen peroxide in AZ under water-deficit stress. The cell separation of the pulvinus AZ also delayed in co-overexpression of the ROS-scavenging proteins SOD and CAT1 plants both in vitro and at the plant level. Together, the results indicated that ROS play an important regulatory role in the process of cassava leaf abscission under water-deficit stress. PMID:26899473

  6. [Chemical characterization and quantification of fructooligosaccharides, phenolic compounds and antiradical activity of Andean roots and tubers grown in Northwest of Argentina].

    PubMed

    Jiménez, María Eugenia; Sammán, Norma

    2014-06-01

    There is great interest in consuming foods that can provide the nutrients for a good nutrition and other health beneficial compounds. The aim of this work was to determine the chemical composition of native foods of the Andean region and to quantify some functional com-ponents. Proximal composition, vitamin C, total phenolic compounds, antiradical activity (DPPH) in peel and pulp, dietary fiber soluble and insoluble, fructooligosaccharides (FOS), total and resistant starch (in tubers and raw roots, boiled and boiled and stored) of 6 varieties of Oca (Oxalis tuberosa), 4 clones of manioc (Manihot esculenta Crantz) and yacon (Smallanthus sonchifolius were determined. The results showed greater amount of bioactive compounds and antiradical activity in the skin of these products. The highest content was found in the oca peel. In all cases, the content of insoluble fiber was greater than the soluble. The manioc had higher total starch than Andean roots and tubers. The boiling process decreased the resistant starch content of ocas and maniocs, but when these are stored for 48 h at 5 ° C, the resistant starch content increased. The FOS content of the ocas was similar for all varieties (7%). The main component of yacon carbohydrates were FOS (8.89%). The maniocs did not contain FOS. It can be concluded that the roots and tubers studied, in addition to provide nutrients, contain functional compounds that confer additional helpful value for preventing no communicable diseases. PMID:25799690

  7. Cytokinin-dependent secondary growth determines root biomass in radish (Raphanus sativus L.).

    PubMed

    Jang, Geupil; Lee, Jung-Hun; Rastogi, Khushboo; Park, Suhyoung; Oh, Sang-Hun; Lee, Ji-Young

    2015-08-01

    The root serves as an essential organ in plant growth by taking up nutrients and water from the soil and supporting the rest of the plant body. Some plant species utilize roots as storage organs. Sweet potatoes (Ipomoea batatas), cassava (Manihot esculenta), and radish (Raphanus sativus), for example, are important root crops. However, how their root growth is regulated remains unknown. In this study, we characterized the relationship between cambium and radial root growth in radish. Through a comparative analysis with Arabidopsis root expression data, we identified putative cambium-enriched transcription factors in radish and analysed their expression in representative inbred lines featuring distinctive radial growth. We found that cell proliferation activities in the cambium positively correlated with radial growth and final yields of radish roots. Expression analysis of candidate transcription factor genes revealed that some genes are differentially expressed between inbred lines and that the difference is due to the distinct cytokinin response. Taken together, we have demonstrated for the first time, to the best of our knowledge, that cytokinin-dependent radial growth plays a key role in the yields of root crops. PMID:25979997

  8. Large-Scale Proteomics of the Cassava Storage Root and Identification of a Target Gene to Reduce Postharvest Deterioration.

    PubMed

    Vanderschuren, Hervé; Nyaboga, Evans; Poon, Jacquelyne S; Baerenfaller, Katja; Grossmann, Jonas; Hirsch-Hoffmann, Matthias; Kirchgessner, Norbert; Nanni, Paolo; Gruissem, Wilhelm

    2014-05-29

    Cassava (Manihot esculenta) is the most important root crop in the tropics, but rapid postharvest physiological deterioration (PPD) of the root is a major constraint to commercial cassava production. We established a reliable method for image-based PPD symptom quantification and used label-free quantitative proteomics to generate an extensive cassava root and PPD proteome. Over 2600 unique proteins were identified in the cassava root, and nearly 300 proteins showed significant abundance regulation during PPD. We identified protein abundance modulation in pathways associated with oxidative stress, phenylpropanoid biosynthesis (including scopoletin), the glutathione cycle, fatty acid α-oxidation, folate transformation, and the sulfate reduction II pathway. Increasing protein abundances and enzymatic activities of glutathione-associated enzymes, including glutathione reductases, glutaredoxins, and glutathione S-transferases, indicated a key role for ascorbate/glutathione cycles. Based on combined proteomics data, enzymatic activities, and lipid peroxidation assays, we identified glutathione peroxidase as a candidate for reducing PPD. Transgenic cassava overexpressing a cytosolic glutathione peroxidase in storage roots showed delayed PPD and reduced lipid peroxidation as well as decreased H2O2 accumulation. Quantitative proteomics data from ethene and phenylpropanoid pathways indicate additional gene candidates to further delay PPD. Cassava root proteomics data are available at www.pep2pro.ethz.ch for easy access and comparison with other proteomics data. PMID:24876255

  9. Spatial distribution of mercury and arsenic levels in water, soil and cassava plants in a community with long history of gold mining in Tanzania.

    PubMed

    Nyanza, Elias C; Dewey, Deborah; Thomas, Deborah S K; Davey, Mark; Ngallaba, Sospatro E

    2014-12-01

    This study examined the spatial distribution of total mercury (THg) and total arsenic (TAs) in water, soil and cassava (Manihot esculenta) (leaves and roots) samples taken from areas in Rwamagasa village in northwestern Tanzania where daily living activities occur in close proximity to extensive artisanal and small scale gold mining. Results indicated that 33.3 % of the water sources had THg levels above the WHO guideline of 1.0 µg/L for safe drinking water, and 12.5 % had TAs levels above 10 µg/L. Cassava leaves were found to have higher THg (ranging from 8.3 to 167 µg/kg) and TAs (ranging from 60 to 1,120 µg/kg) levels than cassava roots, which ranged between 1.2-8.3 µg/kg for THg and 25-310 µg/kg for TAs. Concentrations of THg and TAs in soil samples ranged between 5.8-1,759 and 183-20,298 µg/kg, respectively. Both THg and TAs were found to be distributed throughout Rwamagasa village. PMID:24923470

  10. Predicting the potential invasion suitability of regions to cassava lacebug pests (Heteroptera: Tingidae: Vatiga spp.).

    PubMed

    Montemayor, S I; Dellapé, P M; Melo, M C

    2015-04-01

    Cassava (Manihot esculenta Crantz) is one of the most important staple crops for small farmers in the tropics, feeding about 800 million people worldwide. It is currently cultivated in South and Central America, Africa and Asia. The genus Vatiga is widespread throughout the Neotropical region. Its species are sympatric and feed exclusively on cassava. The main objectives of this paper are: (1) to assess the potential distribution of Vatiga, one of the most relevant pests of cassava; (2) to project the resulting models onto the world; (3) to recognize areas with suitable and optimal climates (and thus, high probability) for future colonization, and (4) to compare this model with the harvested area of cassava analyzing the climatic variables required by both the host and the pest species. Species distribution models were built using Maxent (v3.3.3k) with bioclimatic variables from the WorldClim database in 2.5 arc min resolution across the globe. Our model shows that Vatiga has the potential to expand its current distribution into other suitable areas, and could invade other regions where cassava is already cultivated, e.g., Central Africa and Asia. Considering the results and the high host specificity of Vatiga, its recent appearance in Réunion Island (Africa) poses a serious threat, as nearby areas are potentially suitable for invasion and could serve as dispersal routes enabling Vatiga to reach the continent. The present work may help prevention or early detection of Vatiga spp. in areas where cassava is grown. PMID:25523908

  11. Cassava: a basic energy source in the tropics

    SciTech Connect

    Cock, J.H.

    1982-11-19

    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.

  12. Characters related to higher starch accumulation in cassava storage roots.

    PubMed

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

  13. Cassava virus diseases: biology, epidemiology, and management.

    PubMed

    Legg, James P; Lava Kumar, P; Makeshkumar, T; Tripathi, Leena; Ferguson, Morag; Kanju, Edward; Ntawuruhunga, Pheneas; Cuellar, Wilmer

    2015-01-01

    Cassava (Manihot esculenta Crantz.) is the most important vegetatively propagated food staple in Africa and a prominent industrial crop in Latin America and Asia. Its vegetative propagation through stem cuttings has many advantages, but deleteriously it means that pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Cassava-growing continents are characterized by specific suites of viruses that affect cassava and pose particular threats. Of major concern, causing large and increasing economic impact in Africa and Asia are the cassava mosaic geminiviruses that cause cassava mosaic disease in Africa and Asia and cassava brown streak viruses causing cassava brown streak disease in Africa. Latin America, the center of origin and domestication of the crop, hosts a diverse set of virus species, of which the most economically important give rise to cassava frog skin disease syndrome. Here, we review current knowledge on the biology, epidemiology, and control of the most economically important groups of viruses in relation to both farming and cultural practices. Components of virus control strategies examined include: diagnostics and surveillance, prevention and control of infection using phytosanitation, and control of disease through the breeding and promotion of varieties that inhibit virus replication and/or movement. We highlight areas that need further research attention and conclude by examining the likely future global outlook for virus disease management in cassava. PMID:25591878

  14. LINE-1-like retrotransposons contribute to RNA-based gene duplication in dicots.

    PubMed

    Zhu, Zhenglin; Tan, Shengjun; Zhang, Yaqiong; Zhang, Yong E

    2016-01-01

    RNA-based duplicated genes or functional retrocopies (retrogenes) are known to drive phenotypic evolution. Retrogenes emerge via retroposition, which is mainly mediated by long interspersed nuclear element 1 (LINE-1 or L1) retrotransposons in mammals. By contrast, long terminal repeat (LTR) retrotransposons appear to be the major player in plants, although an L1-like mechanism has also been hypothesized to be involved in retroposition. We tested this hypothesis by searching for young retrocopies, as these still retain the sequence features associated with the underlying retroposition mechanism. Specifically, we identified polymorphic retrocopies (retroCNVs) by analyzing public Arabidopsis (Arabidopsis thaliana) resequencing data. Furthermore, we searched for recently originated retrocopies encoded by the reference genome of Arabidopsis and Manihot esculenta. Across these two datasets, we found cases with L1-like hallmarks, namely, the expected target site sequence, a polyA tail and target site duplications. Such data suggest that an L1-like mechanism could operate in plants, especially dicots. PMID:27098918

  15. A geographic distribution database of the Neotropical cassava whitefly complex (Hemiptera, Aleyrodidae) and their associated parasitoids and hyperparasitoids (Hymenoptera).

    PubMed

    Vásquez-Ordóñez, Aymer Andrés; Hazzi, Nicolas A; Escobar-Prieto, David; Paz-Jojoa, Dario; Parsa, Soroush

    2015-01-01

    Whiteflies (Hemiptera, Aleyrodidae) are represented by more than 1,500 herbivorous species around the world. Some of them are notorious pests of cassava (Manihot esculenta), a primary food crop in the tropics. Particularly destructive is a complex of Neotropical cassava whiteflies whose distribution remains restricted to their native range. Despite their importance, neither their distribution, nor that of their associated parasitoids, is well documented. This paper therefore reports observational and specimen-based occurrence records of Neotropical cassava whiteflies and their associated parasitoids and hyperparasitoids. The dataset consists of 1,311 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT's Arthropod Reference Collection (CIATARC, Cali, Colombia). Eleven species of whiteflies, 14 species of parasitoids and one species of hyperparasitoids are reported. Approximately 66% of the whitefly records belong to Aleurotrachelus socialis and 16% to Bemisia tuberculata. The parasitoids with most records are Encarsia hispida, Amitus macgowni and Encarsia bellottii for Aleurotrachelus socialis; and Encarsia sophia for Bemisia tuberculata. The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF). PMID:26798295

  16. Molecular cloning and expression of a novel MYB transcription factor gene in rubber tree.

    PubMed

    Qin, Bi; Zhang, Yu; Wang, Meng

    2014-12-01

    MYB family proteins regulate a variety of cellular processes in plants. Tapping panel dryness (TPD) in rubber tree (Hevea brasiliensis Muell. Arg.) affects latex biosynthesis and causes serious losses to rubber producers. In this study, a novel SANT/MYB transcription factor gene down-regulated in TPD rubber tree, named as HbSM1, was isolated from rubber tree. The complete HbSM1 open reading frame (ORF) was 948 bp in length. The deduced HbSM1 protein is 315 amino acids. HbSM1 belonged to 1RMYB subfamily with a single SANT domain. Sequence alignment revealed that HbSM1 had high homology with MYB members from Ricinus communis and Manihot esculenta, with 72 and 78 % identity, respectively. Moreover, HbSM1 shared 56 % identity with Glycine max GmMYB176. Phylogenetic analysis revealed that HbSM1, GmMYB176, rice OsMYBS2, and OsMYBS3 fell into the same cluster with 93 % bootstrap support value. Comparing expression among different tissues demonstrated that HbSM1 was ubiquitously expressed in all tissues, but it appeared to be preferentially expressed in leaf and latex. Furthermore, HbSM1 transcripts were significantly induced by various phytohormones (including gibberellic acid, ethephon, methyl jasmonate, salicylic acid, and abscisic acid) and wounding treatments. These results suggested that HbSM1 might play multiple roles in plant development via different phytohormones signaling pathways. PMID:25195053

  17. Cassava root membrane proteome reveals activities during storage root maturation.

    PubMed

    Naconsie, Maliwan; Lertpanyasampatha, Manassawe; Viboonjun, Unchera; Netrphan, Supatcharee; Kuwano, Masayoshi; Ogasawara, Naotake; Narangajavana, Jarunya

    2016-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crops of Thailand. Its storage roots are used as food, feed, starch production, and be the important source for biofuel and biodegradable plastic production. Despite the importance of cassava storage roots, little is known about the mechanisms involved in their formation. This present study has focused on comparison of the expression profiles of cassava root proteome at various developmental stages using two-dimensional gel electrophoresis and LC-MS/MS. Based on an anatomical study using Toluidine Blue, the secondary growth was confirmed to be essential during the development of cassava storage root. To investigate biochemical processes occurring during storage root maturation, soluble and membrane proteins were isolated from storage roots harvested from 3-, 6-, 9-, and 12-month-old cassava plants. The proteins with differential expression pattern were analysed and identified to be associated with 8 functional groups: protein folding and degradation, energy, metabolism, secondary metabolism, stress response, transport facilitation, cytoskeleton, and unclassified function. The expression profiling of membrane proteins revealed the proteins involved in protein folding and degradation, energy, and cell structure were highly expressed during early stages of development. Integration of these data along with the information available in genome and transcriptome databases is critical to expand knowledge obtained solely from the field of proteomics. Possible role of identified proteins were discussed in relation with the activities during storage root maturation in cassava. PMID:26547558

  18. Data supporting the role of enzymes and polysaccharides during cassava postharvest physiological deterioration

    PubMed Central

    Uarrota, Virgílio Gavicho; Moresco, Rodolfo; Schmidt, Eder Carlos; Bouzon, Zenilda Laurita; da Costa Nunes, Eduardo; de Oliveira Neubert, Enilto; Peruch, Luiz Augusto Martins; Rocha, Miguel; Maraschin, Marcelo

    2016-01-01

    This data article is referred to the research article entitled The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration by Uarrota et al. (2015). Food Chemistry 197, Part A, 737–746. The stress duo to PPD of cassava roots leads to the formation of ROS which are extremely harmful and accelerates cassava spoiling. To prevent or alleviate injuries from ROS, plants have evolved antioxidant systems that include non-enzymatic and enzymatic defence systems such as ascorbate peroxidase, guaiacol peroxidase and polysaccharides. In this data article can be found a dataset called “newdata”, in RData format, with 60 observations and 06 variables. The first 02 variables (Samples and Cultivars) and the last 04, spectrophotometric data of ascorbate peroxidase, guaiacol peroxidase, tocopherol, total proteins and arcsined data of cassava PPD scoring. For further interpretation and analysis in R software, a report is also provided. Means of all variables and standard deviations are also provided in the Supplementary tables (“data.long3.RData, data.long4.RData and meansEnzymes.RData”), raw data of PPD scoring without transformation (PPDmeans.RData) and days of storage (days.RData) are also provided for data analysis reproducibility in R software. PMID:26900596

  19. A geographic distribution database of the Neotropical cassava whitefly complex (Hemiptera, Aleyrodidae) and their associated parasitoids and hyperparasitoids (Hymenoptera)

    PubMed Central

    Vásquez-Ordóñez, Aymer Andrés; Hazzi, Nicolas A.; Escobar-Prieto, David; Paz-Jojoa, Dario; Parsa, Soroush

    2015-01-01

    Abstract Whiteflies (Hemiptera, Aleyrodidae) are represented by more than 1,500 herbivorous species around the world. Some of them are notorious pests of cassava (Manihot esculenta), a primary food crop in the tropics. Particularly destructive is a complex of Neotropical cassava whiteflies whose distribution remains restricted to their native range. Despite their importance, neither their distribution, nor that of their associated parasitoids, is well documented. This paper therefore reports observational and specimen-based occurrence records of Neotropical cassava whiteflies and their associated parasitoids and hyperparasitoids. The dataset consists of 1,311 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT’s Arthropod Reference Collection (CIATARC, Cali, Colombia). Eleven species of whiteflies, 14 species of parasitoids and one species of hyperparasitoids are reported. Approximately 66% of the whitefly records belong to Aleurotrachelus socialis and 16% to Bemisia tuberculata. The parasitoids with most records are Encarsia hispida, Amitus macgowni and Encarsia bellottii for Aleurotrachelus socialis; and Encarsia sophia for Bemisia tuberculata. The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF). PMID:26798295

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

    SciTech Connect

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

    1981-02-01

    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.

  1. High-throughput microarray mapping of cell wall polymers in roots and tubers during the viscosity-reducing process.

    PubMed

    Huang, Yuhong; Willats, William G; Lange, Lene; Jin, Yanling; Fang, Yang; Salmeán, Armando A; Pedersen, Henriette L; Busk, Peter Kamp; Zhao, Hai

    2016-03-01

    Viscosity reduction has a great impact on the efficiency of ethanol production when using roots and tubers as feedstock. Plant cell wall-degrading enzymes have been successfully applied to overcome the challenges posed by high viscosity. However, the changes in cell wall polymers during the viscosity-reducing process are poorly characterized. Comprehensive microarray polymer profiling, which is a high-throughput microarray, was used for the first time to map changes in the cell wall polymers of sweet potato (Ipomoea batatas), cassava (Manihot esculenta), and Canna edulis Ker. over the entire viscosity-reducing process. The results indicated that the composition of cell wall polymers among these three roots and tubers was markedly different. The gel-like matrix and glycoprotein network in the C. edulis Ker. cell wall caused difficulty in viscosity reduction. The obvious viscosity reduction of the sweet potato and the cassava was attributed to the degradation of homogalacturonan and the released 1,4-β-d-galactan and 1,5-α-l-arabinan. PMID:25757626

  2. Augmenting iron accumulation in cassava by the beneficial soil bacterium Bacillus subtilis (GBO3).

    PubMed

    Freitas, Mônica A; Medeiros, Flavio H V; Carvalho, Samuel P; Guilherme, Luiz R G; Teixeira, William D; Zhang, Huiming; Paré, Paul W

    2015-01-01

    Cassava (Manihot esculenta), a major staple food in the developing world, provides a basic carbohydrate diet for over half a billion people living in the tropics. Despite the iron abundance in most soils, cassava provides insufficient iron for humans as the edible roots contain 3-12 times less iron than other traditional food crops such as wheat, maize, and rice. With the recent identification that the beneficial soil bacterium Bacillus subtilis (strain GB03) activates iron acquisition machinery to increase metal ion assimilation in Arabidopsis, the question arises as to whether this plant-growth promoting rhizobacterium also augments iron assimilation to increase endogenous iron levels in cassava. Biochemical analyses reveal that shoot-propagated cassava with GB03-inoculation exhibit elevated iron accumulation after 140 days of plant growth as determined by X-ray microanalysis and total foliar iron analysis. Growth promotion and increased photosynthetic efficiency were also observed for greenhouse-grown plants with GB03-exposure. These results demonstrate the potential of microbes to increase iron accumulation in an important agricultural crop and is consistent with idea that microbial signaling can regulate plant photosynthesis. PMID:26300897

  3. Development of a cassava core collection based on single nucleotide polymorphism markers.

    PubMed

    Oliveira, E J; Ferreira, C F; Santos, V S; Oliveira, G A F

    2014-01-01

    Single nucleotide polymorphism (SNP) markers were used in the largest cassava (Manihot esculenta Crantz) germplasm collection from Brazil to develop core collections based on the maximization strategy. Subsets with 61, 64, 84, 128, 256, and 384 cassava accessions were selected and named PoHEU, MST64, PoRAN, MST128, MST256, and MST384, respectively. All the 798 alleles identified by 402 SNP markers in the entire collection were captured in all core collections. Only small alterations in the diversity parameters were observed for the different core collections compared with the complete collection. Because of the optimal adjustment of the validation parameters representative of the complete collection, the absence of genotypes with high genetic similarity and the maximization of the genetic distances between accessions of the PoHEU core collection, which contained 4.7% of the accessions of the complete collection, maximized the genetic conservation of this important cassava collection. Furthermore, the development of this core collection will allow concentrated efforts toward future characterization and agronomic evaluation of accessions to maximize the diversity and genetic gains in cassava breeding programs. PMID:25158266

  4. Cytokinin-dependent secondary growth determines root biomass in radish (Raphanus sativus L.)

    PubMed Central

    Jang, Geupil; Lee, Jung-Hun; Rastogi, Khushboo; Park, Suhyoung; Oh, Sang-Hun; Lee, Ji-Young

    2015-01-01

    The root serves as an essential organ in plant growth by taking up nutrients and water from the soil and supporting the rest of the plant body. Some plant species utilize roots as storage organs. Sweet potatoes (Ipomoea batatas), cassava (Manihot esculenta), and radish (Raphanus sativus), for example, are important root crops. However, how their root growth is regulated remains unknown. In this study, we characterized the relationship between cambium and radial root growth in radish. Through a comparative analysis with Arabidopsis root expression data, we identified putative cambium-enriched transcription factors in radish and analysed their expression in representative inbred lines featuring distinctive radial growth. We found that cell proliferation activities in the cambium positively correlated with radial growth and final yields of radish roots. Expression analysis of candidate transcription factor genes revealed that some genes are differentially expressed between inbred lines and that the difference is due to the distinct cytokinin response. Taken together, we have demonstrated for the first time, to the best of our knowledge, that cytokinin-dependent radial growth plays a key role in the yields of root crops. PMID:25979997

  5. Identification of Cassava MicroRNAs under Abiotic Stress

    PubMed Central

    Ballén-Taborda, Carolina; Plata, Germán; Ayling, Sarah; Rodríguez-Zapata, Fausto; Tohme, Joe

    2013-01-01

    The study of microRNAs (miRNAs) in plants has gained significant attention in recent years due to their regulatory role during development and in response to biotic and abiotic stresses. Although cassava (Manihot esculenta Crantz) is tolerant to drought and other adverse conditions, most cassava miRNAs have been predicted using bioinformatics alone or through sequencing of plants challenged by biotic stress. Here, we use high-throughput sequencing and different bioinformatics methods to identify potential cassava miRNAs expressed in different tissues subject to heat and drought conditions. We identified 60 miRNAs conserved in other plant species and 821 potential cassava-specific miRNAs. We also predicted 134 and 1002 potential target genes for these two sets of sequences. Using real time PCR, we verified the condition-specific expression of 5 cassava small RNAs relative to a non-stress control. We also found, using publicly available expression data, a significantly lower expression of the predicted target genes of conserved and nonconserved miRNAs under drought stress compared to other cassava genes. Gene Ontology enrichment analysis along with condition specific expression of predicted miRNA targets, allowed us to identify several interesting miRNAs which may play a role in stress-induced posttranscriptional regulation in cassava and other plants. PMID:24328029

  6. Enhanced butanol production from cassava with Clostridium acetobutylicum by genome shuffling.

    PubMed

    Li, Shu-Bo; Qian, Yi; Liang, Zheng-Wu; Guo, Yuan; Zhao, Mou-Ming; Pang, Zong-Wen

    2016-04-01

    To obtain strains exhibiting high levels of solvent tolerance and butanol production, wild type strains of Clostridium acetobutylicum butanol-producing strain GX01 and Lactobacillus mucosae butanol-tolerant strain M26 were subjected to mutagenesis combining N-methyl-N-nitro-N-nitrosoguanidine induction with genome shuffling. After four successive rounds of genome shuffling, the C. acetobutylicum shuffled strain GS4-3 showing greater levels of fermentation performances (such as secreting a higher level of amylase, improving the thermal stability, and possessing greater environmental robustness) compared to the wild type strains was isolated. As a result, after optimization of culture conditions, mutant GS4-3 produced 32.6 g/L of total solvent, 20.1 g/L of butanol production, and 0.35 g/L/h of butanol productivity, which were, respectively, increased by 23.5, 23.3, and 40.0 % than the wild-type strain GX01, in a 10 L bioreactor. The enhanced production of butanol and tolerance of solvent of mutant associated with GS4-3 make it promising for acetone/butanol/ethanol fermentation from cassava (Manihot esculenta). Compared to the parental strain (blue), the shuffled strain exhibited the more excellent performances for butanol production from different carbon sources. PMID:26925615

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

    PubMed Central

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

    2007-01-01

    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

  8. Cassava: constraints to production and the transfer of biotechnology to African laboratories.

    PubMed

    Bull, Simon E; Ndunguru, Joseph; Gruissem, Wilhelm; Beeching, John R; Vanderschuren, Hervé

    2011-05-01

    Knowledge and technology transfer to African institutes is an important objective to help achieve the United Nations Millennium Development Goals. Plant biotechnology in particular enables innovative advances in agriculture and industry, offering new prospects to promote the integration and dissemination of improved crops and their derivatives from developing countries into local markets and the global economy. There is also the need to broaden our knowledge and understanding of cassava as a staple food crop. Cassava (Manihot esculenta Crantz) is a vital source of calories for approximately 500 million people living in developing countries. Unfortunately, it is subject to numerous biotic and abiotic stresses that impact on production, consumption, marketability and also local and country economics. To date, improvements to cassava have been led via conventional plant breeding programmes, but with advances in molecular-assisted breeding and plant biotechnology new tools are being developed to hasten the generation of improved farmer-preferred cultivars. In this review, we report on the current constraints to cassava production and knowledge acquisition in Africa, including a case study discussing the opportunities and challenges of a technology transfer programme established between the Mikocheni Agricultural Research Institute in Tanzania and Europe-based researchers. The establishment of cassava biotechnology platform(s) should promote research capabilities in African institutions and allow scientists autonomy to adapt cassava to suit local agro-ecosystems, ultimately serving to develop a sustainable biotechnology infrastructure in African countries. PMID:21212961

  9. Comparative study on the conventional and non thermal simultaneous saccharification and fermentation of Manihot glaziovii root starch

    NASA Astrophysics Data System (ADS)

    Hargono, Kumoro, Andri Cahyo; Jos, Bakti

    2015-12-01

    Inconventional ethanol production process, starch is converted into dextrins via liquefaction using α-amylase enzyme at high temperature (90-120°C). Then, dextrins are saccharified by glucoamylase to obtain to monomeric sugars (glucose). Recently, a granular starch hydrolyzing enzymes (GSHE), Stargen 002, was developed to convert starch into dextrins at low temperature (< 32°C) and hydrolyzes dextrins into glucose. The subject of this research was to compare ethanol production using a granular starch hydrolyzing enzymes and conventional enzymatic liquefaction and saccharification in cassava starch processing. Starch slurry concentrations were 20% w/v, and dosage of enzymes 0.50, 1.0 and 2%, respectively, were studied. After 48 hr process the final ethanol concentration for the respective enzyme concentration for conventional process were 34.90, 36.16 and 42.10 g/L, whereas for the non-thermal treatment, final ethanol concentration were 46.4, 57.62 and 59.65 g/L, respectively. By implementation of this non thermal process, the use of energy can be saved by carrying out saccharification step at lower temperature (30°C) could be realized.

  10. Impact of style of processing on retention and bioaccessibility of beta-carotene in cassava (Manihot esculanta, Crantz).

    PubMed

    Thakkar, Sagar K; Huo, Tianyao; Maziya-Dixon, Bussie; Failla, Mark L

    2009-02-25

    We previously demonstrated that the quantity of beta-carotene (BC) partitioning in mixed micelles during simulated small intestinal digestion, i.e., the bioaccessibility, of boiled cassava is highly correlated with the BC content of different cultivars. However, cassava is also traditionally prepared by fermentation and roasting. These different methods of preparation have the potential to affect both the retention and bioaccessibility of BC. Here, we first compared retention of BC in boiled cassava, gari (fermentation followed by roasting), and fufu (fermentation followed by sieving and cooking into a paste) prepared from roots of three cultivars. BC content in unprocessed cultivars ranged from 6-8 microg/g wet weight, with cis isomers accounting for approximately one-third of total BC. Apparent retention of BC was approximately 90% for boiled cassava and fufu. In contrast, roasting fermented cassava at 195 degrees C for 20 min to prepare gari decreased BC content by 90%. Retention was increased to 63% when temperature was decreased to 165 degrees C and roasting was limited to 10 min. Processing was also associated with a decline in all-trans-BC and concomitant increase in 13-cis-BC. The efficiency of micellarization of all-trans and cis isomers of BC during simulated digestion was 25-30% for boiled cassava and gari and independent of cultivar. However, micellarization of BC isomers during digestion of fufu was only 12-15% (P < 0.05). These differences in retention and bioaccessibility of BC from cassava products prepared according to traditional processing methods suggest that gari and fufu may provide less retinol activity equivalents than isocaloric intake of boiled cassava. PMID:19199597

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

    SciTech Connect

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

    1990-09-01

    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.

  12. Physicochemical and thermal properties of taro (Colocasia esculenta sp) powders as affected by state of maturity and drying method.

    PubMed

    Himeda, M; Njintang, Y N; Gaiani, C; Nguimbou, R M; Scher, J; Facho, B; Mbofung, C M F

    2014-09-01

    The study was aimed at determining the effect of harvesting time and drying method on the thermal and physicochemical properties of taro powder, Sosso ecotype. A 5 × 2 factorial experiment with 5 harvesting times (6, 7, 8, 9 and 10 months after planting) and 2 drying methods (sun and electric oven drying) was used for this purpose. The variance component analysis revealed harvesting time as the most important factor affecting all the variables measured. In particular the proteins and available sugar contents of the powders increased significantly with increase in harvesting time. The same was true of the gelling property and water absorption capacity of the powders. It was equally observed that the temperatures (start, peak and end) and enthalpy of gelatinization of the powders increased with harvesting time. It is concluded that harvesting sosso-taro at full maturity (10 months after planting) and sun-drying produces food powders with excellent gelling properties among others. PMID:25190840

  13. Physical, functional, and pasting properties of flours from corms of two Cocoyam (Colocasia esculenta and Xanthosoma sagittifolium) cultivars.

    PubMed

    Falade, Kolawole O; Okafor, Chidinma A

    2015-06-01

    Physical, functional and physicochemical properties of flours of five cocoyam (Colocasia spp and Xanthosoma spp) cultivars were evaluated. Colour (L*a*b*) parameters of corms and flours, pasting and functional properties of the flours were determined. Xanthosoma spp showed significantly higher length (95.16-151.46), width (75.29-78.03) and weight (179.20-605.94) than the Colocasia spp., but the parameters did not vary significantly within either Xanthosoma and Colocasia spp. Generally, colour of peeled corms [L* (72.08-78.93); a* (+1.06 - +3.5); b* (+17.65 - +35.80)] was lighter than the flours [L* (69.35-84.97); a* (+0.30 - + 4.76); b* (+4.44 - +23.48)]. The NXs001 showed significantly higher peak (201.71RVU), trough (186.75 RVU), final (289.75 RVU) and setback (103 RVU) viscosities that the other cultivars. Pasting profiles of the cocoyam flours showed similar trend with the NXs001 showing a steeper curve. Pasting temperature and peak time ranged from 87.33 to 92.53 °C and 5.17-6.34 min, respectively. Water absorption capacity, gelling point, pH, foam capacity, bulk density and swelling power varied from 32-69 %, 6.56-7.59, 58.5-72.5 °C, 7.19-14.72 %, 0.94-1.01 g/mL and 3.18-7.36, respectively. PMID:26028725

  14. Empowering biotechnology in southern Africa: establishment of a robust transformation platform for the production of transgenic industry-preferred cassava.

    PubMed

    Chetty, C C; Rossin, C B; Gruissem, W; Vanderschuren, H; Rey, M E C

    2013-01-25

    Knowledge and technology transfer to African laboratories and farmers is an important objective for achieving food security and sustainable crop production on the sub-Saharan African continent. Cassava (Manihot esculenta Crantz) is a vital source of calories for more than a billion people in developing countries, and its potential industrial use for starch and bioethanol in the tropics is increasingly being recognized. However, cassava production remains constrained by the susceptibility of the crop to several biotic and abiotic stresses. For more than a decade, biotechnology has been considered an attractive tool to improve cassava as it substantially circumvents the limitations of traditional breeding, which is particularly time-consuming and tedious because of the high heterozygosity of the crop. A major constraint to the development of biotechnological approaches for cassava improvement has been the lack of an efficient and robust transformation and regeneration system. Despite some success achieved in genetic modification of the model cassava cultivar Tropical Manihot Series (TMS), TMS 60444, in some European and U.S. laboratories, the lack of a reproducible and robust protocol has not allowed the establishment of a routine transformation system in sub-Saharan Africa. In this study, we optimized a robust and efficient protocol developed at ETH Zurich to successfully establish transformation of a commercially cultivated South African landrace, T200, and compared this with the benchmark model cultivar TMS 60444. Results from our study demonstrated high transformation rates for both T200 (23 transgenic lines from 100 friable embryogenic callus (FEC) clusters) compared with TMS 60444 (32 transgenic lines from 100 FEC clusters). The success in transforming landraces or farmer-preferred cultivars has been limited, and the high transformation rate of an industry-preferred landrace in this study is encouraging for a feasible transformation program for cassava improvement in South Africa (SA), which can potentially be extended to other countries in southern Africa. The successful establishment of a robust cassava transformation and regeneration system in SA demonstrates the relevance of technology transfer to sub-Saharan Africa and highlights the importance of developing suitable and reliable techniques before their transfer to laboratories offering less optimal conditions. PMID:22683498

  15. Potential of tannin-rich plants for modulating ruminal microbes and ruminal fermentation in sheep.

    PubMed

    Rira, M; Morgavi, D P; Archimède, H; Marie-Magdeleine, C; Popova, M; Bousseboua, H; Doreau, M

    2015-01-01

    The objective of this work was to study nutritional strategies for decreasing methane production by ruminants fed tropical diets, combining in vitro and in vivo methods. The in vitro approach was used to evaluate the dose effect of condensed tannins (CT) contained in leaves of Gliricidia sepium, Leucaena leucocephala, and Manihot esculenta (39, 75, and 92 g CT/kg DM, respectively) on methane production and ruminal fermentation characteristics. Tannin-rich plants (TRP) were incubated for 24 h alone or mixed with a natural grassland hay based on Dichanthium spp. (control plant), so that proportions of TRP were 0, 0.25, 0.5, 0.75, and 1.0. Methane production, VFA concentration, and fermented OM decreased with increased proportions of TRP. Numerical differences on methane production and VFA concentration among TRP sources may be due to differences in their CT content, with greater effects for L. leucocephala and M. esculenta than for G. sepium. Independently of TRP, the response to increasing doses of CT was linear for methane production but quadratic for VFA concentration. As a result, at moderate tannin dose, methane decreased more than VFA. The in vivo trial was conducted to investigate the effect of TRP on different ruminal microbial populations. To this end, 8 rumen-cannulated sheep from 2 breeds (Texel and Blackbelly) were used in two 4 × 4 Latin square designs. Diets were fed ad libitum and were composed of the same feeds used for the in vitro trial: control plant alone or combined with pellets made from TRP leaves at 44% of the diet DM. Compared to TRP, concentration of Ruminococcus flavefaciens was greater for the control diet and concentration of Ruminococcus albus was least for the control diet. The methanogen population was greater for Texel than for Blackbelly. By contrast, TRP-containing diets did not affect protozoa or Fibrobacter succinogenes numbers. Hence, TRP showed potential for mitigating methane production by ruminants. These findings suggest that TRP fed as pellets could be used to decrease methane production. PMID:25568379

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

    PubMed Central

    2012-01-01

    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. PMID:22361011

  17. AFLP-based transcript profiling for cassava genome-wide expression analysis in the onset of storage root formation.

    PubMed

    Sojikul, Punchapat; Kongsawadworakul, Panida; Viboonjun, Unchera; Thaiprasit, Jittrawan; Intawong, Burapat; Narangajavana, Jarunya; Svasti, Mom Rajawong Jisnuson

    2010-10-01

    Cassava (Manihot esculenta Crantz) is a root crop that accumulates large quantities of starch, and it is an important source of carbohydrate. Study on gene expressions during storage root development provides important information on storage root formation and starch accumulation as well as unlock new traits for improving of starch yield. cDNA-Amplified Fragment Length Polymorphism (AFLP) was used to compare gene expression profiles in fibrous and storage roots of cassava cultivar Kasetsart 50. Total of 155 differentially expressed transcript-derived fragments with undetectable or low expression in leaves were characterized and classified into 11 groups regarding to their functions. The four major groups were no similarity (20%), hypothetical or unknown proteins (17%), cellular metabolism and biosynthesis (17%) and cellular communication and signaling (14%). Interestingly, sulfite reductase (MeKD82), calcium-dependent protein kinase (CDPK) (MeKD83), ent-kaurene synthase (KS) (MeKD106) and hexose transporter (HT) (MeKD154) showed root-specific expression patterns. This finding is consistent with previously reported genes involved in the initiation of potato tuber. Semi-quantitative reverse transcription polymerase chain reaction of early-developed root samples confirmed that those four genes exhibited significant expression with similar pattern in the storage root initiation and early developmental stages. We proposed that KS and HT may involve in transient induction of CDPK expression, which may play an important role in the signaling pathway of storage root initiation. Sulfite reductase, on the other hand, may involve in storage root development by facilitating sulfur-containing protein biosynthesis or detoxifying the cyanogenic glucoside content through aspartate biosynthesis. PMID:20536786

  18. Feed Intake, Digestibility, and N Retention in Cattle Fed Rice Straw and Para Grass Combined with Different Levels of Protein Derived from Cassava Foliage

    PubMed Central

    Sath, K.; Sokun, K.; Pauly, T.; Holtenius, K.

    2012-01-01

    Eight male cattle of Local Yellow breed with an average live weight of 121 kg and an average age of 18 months were used to evaluate the effects of different levels of sun-dried cassava foliage supplementation (Manihot esculenta) on intake, digestibility and N retention. Rice straw ad libitum and para grass (Brachiaria mutica) at 1% DM of BW comprised the basal diet. The study was arranged as a 4×4 double Latin square design, with cassava foliage contributing 0, 0.8, 1.6 or 2.4 g CP/kg BW. The cattle selected cassava leaves in preference to petioles. Petiole intake decreased from 64 to 48% of offered petioles when the cassava foliage proportion increased from the lowest to the highest level. The cattle consumed all the leaves at the two lower levels of cassava foliage inclusion and 91% at the highest level. Rice straw intake decreased significantly as the level of cassava foliage increased. Intake of DM, OM, NDF, and ADF increased significantly with increasing intake of cassava foliage. Daily DM intake per 100 kg BW increased from 2.7 to 3.2 kg with increasing cassava foliage intake. No effect on CP digestibility was detected when the level of cassava foliage increased. Digestibility of DM, OM, NDF and ADF was significantly higher in the group fed no cassava foliage than in the other groups. N retention increased from 16 to 28 g/d with the first level of cassava foliage inclusion, but levelled out at the two highest levels. N excretion increased in both faeces and urine as a response to higher intake of cassava foliage. Maximum N retention occurred when 40% of total N intake came from cassava foliage (equivalent to 1.3 g CP/kg BW). PMID:25049650

  19. Correlation of Chemical Compositions of Cassava Varieties to Their Resistance to Prostephanus truncatus Horn (Coleoptera: Bostrichidae)

    PubMed Central

    Osipitan, Adebola A.; Sangowusi, Victoria T.; Lawal, Omoniyi I.; Popoola, Kehinde O.

    2015-01-01

    The preference of cassava as a major host by Prostephanus truncatus Horn is a major constraint to ample production of cassava, Manihot esculenta Crantz and storage. This study analyzed the nutritional and secondary metabolite compositions in 15 cassava varieties, evaluated levels of damage and reproduction by P. truncatus, and assessed their resistance to attack. One hundred grams of dried cassava chips in 250-ml Kilner jars were infested with 10 adult larger grain borerof 0–10 days old and held for 3 months. The nutritional and secondary metabolites compositions of the dry cassava chips were determined using the method of Association of Analytical Chemists . Chip perforation rates in the cassava varieties ranged from 17.7 to 71.6%. The weight of cassava powder varied by about threefold. The final number of larger grain borer in the cassava varieties varied by about sixfold with 63 in 01/0040 and 379 in 01/1368. Hydrocyanic acid content content varied by over 10-fold and correlated negatively with number of larger grain borer. Flavonoid content varied by ∼10%. Tannins and saponin content of the cassava negatively correlated with number of adult P. truncatus. The cassava varieties 95/0166, 92/0326, 01/0040, 05/0024, and 34 91934 had selection index <0.8 and were classified as resistant to larger grain borer damage, while others with selection index >0.8 were classified as susceptible. The resistance to high damage in the resistant varieties was conferred by secondary metabolites such as tannins, saponins, alkaloids, and hydrocyanic acid content. The genetic variation in cassava varieties could be explored to breed resistant cassava varieties for use in larger grain borer-endemic areas. PMID:25700536

  20. Effect of tapioca starch and amyloglucosidase concentration on very high gravity simultaneous saccharification and fermentation (VHG-SSF) of bioethanol

    NASA Astrophysics Data System (ADS)

    Sugih, A. K.; Santoso, I. V.; Kristijarti, A. P.

    2015-12-01

    Tapioca starch is isolated from the root of cassava plant (Manihot esculenta). It is produced in a large quantity in Indonesia and other south east Asian countries. Tapioca starch has been commonly used as a feedstock for food as well as non-food industries. Due to its high carbohydrate content, tapioca starch has the potentiality to be used as a raw material for bioethanol production. In this research, a novel approach (Very High Gravity Simultaneous Sacharification and Fermentation/ VHG-SSF) to synthesise highly concentrated ethanol from tapioca starch was investigated. Tapioca starch suspension was first gelatinised for two hours at 90°C and hydrolised at the same temperature for another two hours using commercial α- amylase (Liquozyme Supra, 0.16%-v/ w starch). The pretreated suspension was sterilised and mixed with nitrogenous supplement. In order to start the fermentation, Saccharomyces cereviseae NRRL Y-132 inoculum (10%-v/v; 107 cells/ ml) and commercial amyloglucosidase (Dextrozyme GA, 35-105 AGU/ g starch) were added to the mixture. The initial total carbohydrate, yeast extract, and peptone concentrations of the fermentation broths were 30-40 %-w/v, 1%-w/v, and 2%-w/v, respectively. VHG-SSF was allowed to proceed for 6 days at 30°C with rotary shaker speed of 100 rpm. The concentration of glucose and ethanol during fermentation was monitored using HPLC. The experimental result shows that tapioca starch has been successfully converted to ethanol with a final concentration of 10.12-16.14 %-w/v, which is corresponding to yield of 34.68-56.83 %-w ethanol/ w-converted sugar. The result suggests that VHG-SSF is a prospective method to synthesise bioethanol from tapioca starch.

  1. Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits

    PubMed Central

    Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

    2016-01-01

    Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develop commercial cassava varieties with amylose-free starch. However, little information is available regarding the biological and agronomic implications of starch mutations in cassava, nor in other root and tuber crops. In this study, siblings from eight full-sib families, segregating for the waxy trait, were used to determine if the mutation has implications for yield, dry matter content (DMC) and harvest index in cassava. A total of 87 waxy and 87 wild-type starch genotypes from the eight families were used in the study. The only significant effect of starch type was on DMC (p < 0.01), with waxy clones having a 0.8% lower content than their wild type counterparts. There was no effect of starch type on fresh root yield (FRY), adjusted FRY and harvest index. It is not clear if lower DMC is a pleiotropic effect of the waxy starch mutation or else the result of linked genes introgressed along with the mutation. It is expected that commercial waxy cassava varieties will have competitive FRYs but special efforts will be required to attain adequate DMCs. This study contributes to the limited knowledge available of the impact of starch mutations on the agronomic performance of root and tuber crops.

  2. Research on Motor Neuron Diseases Konzo and Neurolathyrism: Trends from 1990 to 2010

    PubMed Central

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

    2012-01-01

    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

  3. Enhanced Reactive Oxygen Species Scavenging by Overproduction of Superoxide Dismutase and Catalase Delays Postharvest Physiological Deterioration of Cassava Storage Roots1[C][W][OA

    PubMed Central

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

    2013-01-01

    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

  4. Whole genome duplication events in plant evolution reconstructed and predicted using myosin motor proteins

    PubMed Central

    2013-01-01

    Background The evolution of land plants is characterized by whole genome duplications (WGD), which drove species diversification and evolutionary novelties. Detecting these events is especially difficult if they date back to the origin of the plant kingdom. Established methods for reconstructing WGDs include intra- and inter-genome comparisons, KS age distribution analyses, and phylogenetic tree constructions. Results By analysing 67 completely sequenced plant genomes 775 myosins were identified and manually assembled. Phylogenetic trees of the myosin motor domains revealed orthologous and paralogous relationships and were consistent with recent species trees. Based on the myosin inventories and the phylogenetic trees, we have identified duplications of the entire myosin motor protein family at timings consistent with 23 WGDs, that had been reported before. We also predict 6 WGDs based on further protein family duplications. Notably, the myosin data support the two recently reported WGDs in the common ancestor of all extant angiosperms. We predict single WGDs in the Manihot esculenta and Nicotiana benthamiana lineages, two WGDs for Linum usitatissimum and Phoenix dactylifera, and a triplication or two WGDs for Gossypium raimondii. Our data show another myosin duplication in the ancestor of the angiosperms that could be either the result of a single gene duplication or a remnant of a WGD. Conclusions We have shown that the myosin inventories in angiosperms retain evidence of numerous WGDs that happened throughout plant evolution. In contrast to other protein families, many myosins are still present in extant species. They are closely related and have similar domain architectures, and their phylogenetic grouping follows the genome duplications. Because of its broad taxonomic sampling the dataset provides the basis for reliable future identification of further whole genome duplications. PMID:24053117

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

    PubMed

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

    2013-02-01

    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

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

    PubMed

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

    2013-03-01

    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

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

    PubMed

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

    2012-08-01

    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

  8. Informal “Seed” Systems and the Management of Gene Flow in Traditional Agroecosystems: The Case of Cassava in Cauca, Colombia

    PubMed Central

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

    2011-01-01

    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. PMID:22174952

  9. A survey of total hydrocyanic acid content in ready-to-eat cassava-based chips obtained in the Australian market in 2008.

    PubMed

    Miles, David; Jansson, Edward; Mai, My Chi; Azer, Mounir; Day, Peter; Shadbolt, Craig; Stitt, Victoria; Kiermeier, Andreas; Szabo, Elizabeth

    2011-06-01

    Cassava (Manihot esculenta Crantz) is a widely consumed food in the tropics that naturally contains cyanogenic glycosides (cyanogens, mainly composed of linamarin, acetone cyanohydrin, and hydrocyanic acid). If cassava is not adequately processed to reduce the level of cyanogens prior to consumption, these compounds can lead to the formation of hydrocyanic acid in the gut. Exposure to hydrocyanic acid can cause symptoms ranging from vomiting and abdominal pain to coma and death. In 2008, a survey of ready-to-eat (RTE) cassava-based snack foods was undertaken to determine levels of cyanogens measured as total hydrocyanic acid. This survey was undertaken in response to the New South Wales Food Authority being alerted to the detection of elevated levels of cyanogens in an RTE cassava-based snack food. This survey took 374 samples of RTE cassava chips available in the Australian marketplace. Significant variation in the levels of total hydrocyanic acid were observed in the 317 samples testing positive for cyanogens, with levels ranging from 13 to 165 mg of HCN equivalents per kg (mean value, 64.2 mg of HCN eq/kg for positive samples). The results from this survey serve as a timely warning for manufacturers of RTE cassava chips and other cassava-based snack foods to ensure there is tight control over the levels of cyanogens in the cassava ingredient. Evidence from this survey contributed to an amendment to the Australia New Zealand Food Standards Code, which now prescribes a maximum level for hydrocyanic acid in RTE cassava chips of 10 mg of HCN eq/kg, which aligns with the Codex Alimentarius Commission international standard for edible cassava flour. PMID:21669076

  10. A standardized extract of Ginkgo biloba prevents locomotion impairment induced by cassava juice in Wistar rats

    PubMed Central

    Rivadeneyra-Domínguez, Eduardo; Vázquez-Luna, Alma; Rodríguez-Landa, Juan F.; Díaz-Sobac, Rafael

    2014-01-01

    The long-term consumption of cassava (Manihot esculenta Crantz) juice produce neurotoxic effects in the rat, characterized by an increased motor activity in the open field test and presence of uncoordinated swim (i.e., lateral swimming), in the swim test; which has been associated with damage in the hippocampus (CA1). On the other hand, flavonoids content in the Ginkgo biloba extract has been reported to produces neuroprotective effects at experimental level; therefore we hypothesized that G. biloba extract may prevents the motor alterations produced by cassava juice and reduce cellular damage in hippocampal neurons of the rat. In present study the effect of vehicle, cassava juice (linamarin, 0.30 mg/kg), G. biloba extract (dry extract, 160 mg/kg), and combination of treatment were evaluated in the open field and swim tests to identify locomotor and hippocampal alterations in adult male Wistar rats. All treatments were administered once per day, every 24 h, for 28 days, by oral rout. The effect was evaluated at 0, 7, 14, 21, and 28 days of treatment. The results show that cassava group from day 14 of treatment increase crossing and rearing in the open field test, as compared with the vehicle group; while in the swim test produces an uncoordinated swim characterized by the lateral swim. In this same group an increase in the number of damage neurons in the hippocampus (CA1) was identified. Interestingly, both behavioral and neuronal alterations produced by cassava juice administration were prevented by treatment with G. biloba extract. The results shown that G. biloba extract exert a protective effect against behavioral and neuronal damage associated with consumption of cassava juice in the rat. These effects are possibly related with flavonoid content in the G. biloba extract. PMID:25309441

  11. Cassava For Space Diet

    NASA Astrophysics Data System (ADS)

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

    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.

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

    SciTech Connect

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

    1982-09-01

    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 +/.

  13. Correlation of chemical compositions of cassava varieties to their resistance to Prostephanus truncatus Horn (Coleoptera: Bostrichidae).

    PubMed

    Osipitan, Adebola A; Sangowusi, Victoria T; Lawal, Omoniyi I; Popoola, Kehinde O

    2015-01-01

    The preference of cassava as a major host by Prostephanus truncatus Horn is a major constraint to ample production of cassava, Manihot esculenta Crantz and storage. This study analyzed the nutritional and secondary metabolite compositions in 15 cassava varieties, evaluated levels of damage and reproduction by P. truncatus, and assessed their resistance to attack. One hundred grams of dried cassava chips in 250-ml Kilner jars were infested with 10 adult larger grain borerof 0-10 days old and held for 3 months. The nutritional and secondary metabolites compositions of the dry cassava chips were determined using the method of Association of Analytical Chemists . Chip perforation rates in the cassava varieties ranged from 17.7 to 71.6%. The weight of cassava powder varied by about threefold. The final number of larger grain borer in the cassava varieties varied by about sixfold with 63 in 01/0040 and 379 in 01/1368. Hydrocyanic acid content content varied by over 10-fold and correlated negatively with number of larger grain borer. Flavonoid content varied by ∼10%. Tannins and saponin content of the cassava negatively correlated with number of adult P. truncatus. The cassava varieties 95/0166, 92/0326, 01/0040, 05/0024, and 34 91934 had selection index <0.8 and were classified as resistant to larger grain borer damage, while others with selection index >0.8 were classified as susceptible. The resistance to high damage in the resistant varieties was conferred by secondary metabolites such as tannins, saponins, alkaloids, and hydrocyanic acid content. The genetic variation in cassava varieties could be explored to breed resistant cassava varieties for use in larger grain borer-endemic areas. PMID:25700536

  14. Genome-Wide Identification and Expression Analysis of the WRKY Gene Family in Cassava

    PubMed Central

    Wei, Yunxie; Shi, Haitao; Xia, Zhiqiang; Tie, Weiwei; Ding, Zehong; Yan, Yan; Wang, Wenquan; Hu, Wei; Li, Kaimian

    2016-01-01

    The WRKY family, a large family of transcription factors (TFs) found in higher plants, plays central roles in many aspects of physiological processes and adaption to environment. However, little information is available regarding the WRKY family in cassava (Manihot esculenta). In the present study, 85 WRKY genes were identified from the cassava genome and classified into three groups according to conserved WRKY domains and zinc-finger structure. Conserved motif analysis showed that all of the identified MeWRKYs had the conserved WRKY domain. Gene structure analysis suggested that the number of introns in MeWRKY genes varied from 1 to 5, with the majority of MeWRKY genes containing three exons. Expression profiles of MeWRKY genes in different tissues and in response to drought stress were analyzed using the RNA-seq technique. The results showed that 72 MeWRKY genes had differential expression in their transcript abundance and 78 MeWRKY genes were differentially expressed in response to drought stresses in different accessions, indicating their contribution to plant developmental processes and drought stress resistance in cassava. Finally, the expression of 9 WRKY genes was analyzed by qRT-PCR under osmotic, salt, ABA, H2O2, and cold treatments, indicating that MeWRKYs may be involved in different signaling pathways. Taken together, this systematic analysis identifies some tissue-specific and abiotic stress-responsive candidate MeWRKY genes for further functional assays in planta, and provides a solid foundation for understanding of abiotic stress responses and signal transduction mediated by WRKYs in cassava. PMID:26904033

  15. Structural and functional analysis of hydroxynitrile lyase from Baliospermum montanum with crystal structure, molecular dynamics and enzyme kinetics.

    PubMed

    Nakano, Shogo; Dadashipour, Mohammad; Asano, Yasuhisa

    2014-09-16

    Hydroxynitrile lyases (HNLs) catalyze degradation of cyanohydrins to hydrogen cyanide and the corresponding ketone or aldehyde. HNLs can also catalyze the reverse reaction, i.e., synthesis of cyanohydrins. Although several crystal structures of S-selective hydroxynitrile lyases (S-HNLs) have been reported, it remains unknown whether and how dynamics at the active site of S-HNLs influence their broad substrate specificity and affinity. In this study, we analyzed the structure, dynamics and function of S-HNL from Baliospermum montanum (BmHNL), which has an α/β hydrolase fold. Two crystal structures of BmHNL, apo1 and apo2, were determined at 2.55 and 1.9Å, respectively. Structural comparison between BmHNL (apo2) and S-HNL from Hevea brasiliensis with (S)-mandelonitrile bound to the active site revealed that hydrophobic residues at the entrance region of BmHNL formed hydrophobic interactions with the benzene ring of the substrate. The flexible structures of these hydrophobic residues were confirmed by a 15ns molecular dynamics simulation. This flexibility regulated the size of the active site cavity, enabling binding of various substrates to BmHNL. The high affinity of BmHNL toward substrates containing a benzene ring was also confirmed by comparing the kinetics of BmHNL and S-HNL from Manihot esculenta. Taken together, the results indicated that the flexibility and placement of the residues are important for the broad substrate specificity of S-HNLs. PMID:25220808

  16. Influence of material structure on air-borne ultrasonic application in drying.

    PubMed

    Ozuna, César; Gómez Álvarez-Arenas, Tomás; Riera, Enrique; Cárcel, Juan A; Garcia-Perez, Jose V

    2014-05-01

    This work aims to contribute to the understanding of how the properties of the material being dried affect air-borne ultrasonic application. To this end, the experimental drying kinetics (40°C and 1m/s) of cassava (Manihot esculenta) and apple (Malus domestica var. Granny Smith) were carried out applying different ultrasonic powers (0, 6, 12, 19, 25 and 31 kW/m(3)). Furthermore, the power ultrasound-assisted drying kinetics of different fruits and vegetables (potato, eggplant, carrot, orange and lemon peel) already reported in previous studies were also analyzed. The structural, textural and acoustic properties of all these products were assessed, and the drying kinetics modeled by means of the diffusion theory. A significant linear correlation (r>0.95) was established between the identified effective diffusivity (DW) and the applied ultrasonic power for the different products. The slope of this relationship (SDUP) was used as an index of the effectiveness of the ultrasonic application; thus the higher the SDUP, the more effective the ultrasound application. SDUP was well correlated (r ⩾ 0.95) with the porosity and hardness. In addition, SDUP was largely affected by the acoustic impedance of the material being dried, showing a similar pattern with the impedance than the transmission coefficient of the acoustic energy on the interface. Thus, soft and open-porous product structures exhibited a better transmission of acoustic energy and were more prone to the mechanical effects of ultrasound. However, materials with a hard and closed-compact structure were less affected by acoustic energy due to the fact that the significant impedance differences between the product and the air cause high energy losses on the interface. PMID:24411471

  17. Molecular cloning and characterization of a cassava translationally controlled tumor protein gene potentially related to salt stress response.

    PubMed

    Santa Brígida, Ailton Borges; dos Reis, Sávio Pinho; Costa, Carinne de Nazaré Monteirou; Cardoso, Cristina Michiko Yokoyama; Lima, Aline Medeiros; de Souza, Cláudia Regina Batista

    2014-03-01

    Cassava (Manihot esculenta Crantz) is one of the most important tropical crops showing tolerance to abiotic stress and adaptations to a wide range of environmental conditions. Here, we aimed to isolate and characterize the full-length cDNA and genomic sequences of a cassava translationally controlled tumor protein gene (MeTCTP), and evaluate its potential role in response to salt stress. The MeTCTP full-length cDNA sequence encodes for a deduced protein with 168 amino acid residues, with theoretical isoelectric point and molecular weight of 4.53 and 19 kDa, respectively, containing two putative signatures of TCTP family and one site for myristoylation. The MeTCTP genomic sequence includes four introns and five exons within a 1,643 bp coding region, and a 264 bp partial promoter sequence containing several putative cis-acting regulatory elements, among them, two putative GT-1 motifs, which may be related to response to sodium chloride (NaCl) and pathogen infection. Semi-quantitative RT-PCR assays showed that MeTCTP transcripts were higher in roots than leaves, and were significantly increased in detached leaves treated with NaCl. Furthermore, the recombinant MeTCTP conferred a protective function against salt stress in bacterial cells. We report for the first time the molecular cloning and characterization of a cassava TCTP with potential role in salt-stress response. Since salinity is one the most important abiotic factors affecting the production of crops worldwide, the MeTCTP gene could be a candidate gene for generation of salt tolerant crops. PMID:24413992

  18. Genome-Wide Identification and Expression Analysis of the WRKY Gene Family in Cassava.

    PubMed

    Wei, Yunxie; Shi, Haitao; Xia, Zhiqiang; Tie, Weiwei; Ding, Zehong; Yan, Yan; Wang, Wenquan; Hu, Wei; Li, Kaimian

    2016-01-01

    The WRKY family, a large family of transcription factors (TFs) found in higher plants, plays central roles in many aspects of physiological processes and adaption to environment. However, little information is available regarding the WRKY family in cassava (Manihot esculenta). In the present study, 85 WRKY genes were identified from the cassava genome and classified into three groups according to conserved WRKY domains and zinc-finger structure. Conserved motif analysis showed that all of the identified MeWRKYs had the conserved WRKY domain. Gene structure analysis suggested that the number of introns in MeWRKY genes varied from 1 to 5, with the majority of MeWRKY genes containing three exons. Expression profiles of MeWRKY genes in different tissues and in response to drought stress were analyzed using the RNA-seq technique. The results showed that 72 MeWRKY genes had differential expression in their transcript abundance and 78 MeWRKY genes were differentially expressed in response to drought stresses in different accessions, indicating their contribution to plant developmental processes and drought stress resistance in cassava. Finally, the expression of 9 WRKY genes was analyzed by qRT-PCR under osmotic, salt, ABA, H2O2, and cold treatments, indicating that MeWRKYs may be involved in different signaling pathways. Taken together, this systematic analysis identifies some tissue-specific and abiotic stress-responsive candidate MeWRKY genes for further functional assays in planta, and provides a solid foundation for understanding of abiotic stress responses and signal transduction mediated by WRKYs in cassava. PMID:26904033

  19. Genetic parameters and prediction of genotypic values for root quality traits in cassava using REML/BLUP.

    PubMed

    Oliveira, E J; Santana, F A; Oliveira, L A; Santos, V S

    2014-01-01

    The aim of this study was to estimate the genetic parameters and predict the genotypic values of root quality traits in cassava (Manihot esculenta Crantz) using restricted maximum likelihood (REML) and best linear unbiased prediction (BLUP). A total of 471 cassava accessions were evaluated over two years of cultivation. The evaluated traits included amylose content (AML), root dry matter (DMC), cyanogenic compounds (CyC), and starch yield (StYi). Estimates of the individual broad-sense heritability of AML were low (hg(2) = 0.07 ± 0.02), medium for StYi and DMC, and high for CyC. The heritability of AML was substantially improved based on mean of accessions (hm(2) = 0.28), indicating that some strategies such as increasing the number of repetitions can be used to increase the selective efficiency. In general, the observed genotypic values were very close to the predicted average of the improved population, most likely due to the high accuracy (>0.90), especially for DMC, CyC, and StYi. Gains via selection of the 30 best genotypes for each trait were 4.8 and 3.2% for an increase and decrease for AML, respectively, an increase of 10.75 and 74.62% for DMC for StYi, respectively, and a decrease of 89.60% for CyC in relation to the overall mean of the genotypic values. Genotypic correlations between the quality traits of the cassava roots collected were generally favorable, although they were low in magnitude. The REML/BLUP method was adequate for estimating genetic parameters and predicting the genotypic values, making it useful for cassava breeding. PMID:25177949

  20. Improvement of the amides forming capacity of the arylacetonitrilase from Pseudomonas fluorescens EBC191 by site-directed mutagenesis.

    PubMed

    Sosedov, Olga; Stolz, Andreas

    2015-03-01

    The influence of different amino acid substitutions in the nitrilase from Pseudomonas fluorescens EBC191 (NitA) on the catalytical activity and the ability to form amides was investigated. The enzyme variant Glu137Ala was constructed because glutamate residues homologous to Glu137 are highly conserved among different members of the nitrilase superfamily and it has been suggested that these residues are indispensable for the hydrolysis of amides by enzymes belonging to the nitrilase superfamily. The enzyme variant Glu137Ala demonstrated less than 1 % of the wild-type activity but was still enzymatically competent to convert mandelonitrile to mandelic acid and mandeloamide. The tryptophan residue at position 188, which was previously identified as important for the amide forming capacity of the nitrilase, was exchanged by saturation mutagenesis for all other proteinogenic amino acids. Surprisingly, 18 of these 19 exchanges resulted in an increased formation of mandeloamide from (R,S)-mandelonitrile and three of these variants converted (R,S)-mandelonitrile to more than 90 % of mandeloamide. Furthermore, these modifications also resulted in a reversal of stereoselectivity and these variants formed in contrast to the wild-type enzyme and almost all other known nitrilases preferentially (S)-mandelic acid. The synthetic potential of one of these variants was demonstrated by the construction of recombinant E. coli clones which simultaneously expressed the nitrilase variant and the (S)-hydroxynitrile lyase (oxynitrilase) from the cassava plant (Manihot esculenta). These "bienzymatic catalysts" converted benzaldehyde plus cyanide almost exclusively to (S)-mandeloamide and did not show any inhibition in the presence of cyanide in concentrations up to 200 mM. PMID:25248440

  1. Conversion of Sterically Demanding α,α-Disubstituted Phenylacetonitriles by the Arylacetonitrilase from Pseudomonas fluorescens EBC191

    PubMed Central

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

    2012-01-01

    The nitrilase from Pseudomonas fluorescens EBC191 converted 2-methyl-2-phenylpropionitrile, which contains a quaternary carbon atom in the α-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. PMID:22020513

  2. Antibacterial activities of the methanol extracts of ten Cameroonian vegetables against Gram-negative multidrug-resistant bacteria

    PubMed Central

    2013-01-01

    Background Many edible plants are used in Cameroon since ancient time to control microbial infections. This study was designed at evaluating the antibacterial activities of the methanol extracts of ten Cameroonian vegetables against a panel of twenty nine Gram negative bacteria including multi-drug resistant (MDR) strains. Methods The broth microdilution method was used to determine the Minimal Inhibitory Concentrations (MIC) and the Minimal Bactericidal Concentrations (MBC) of the studied extracts. When chloramphenicol was used as a reference antibiotic, the MICs were also determined in the presence of Phenylalanine-Arginine β-Naphtylamide (PAβN), an efflux pumps inhibitor (EPI). The phytochemical screening of the extracts was performed using standard methods. Results All tested extracts exhibited antibacterial activities, with the MIC values varying from 128 to 1024 mg/L. The studied extracts showed large spectra of action, those from L. sativa, S. edule, C. pepo and S. nigrum being active on all the 29 bacterial strains tested meanwhile those from Amaranthus hybridus, Vernonia hymenolepsis, Lactuca.carpensis and Manihot esculenta were active on 96.55% of the strains used. The plant extracts were assessed for the presence of large classes of secondary metabolites: alkaloids, anthocyanins, anthraquinones, flavonoids, phenols, saponins, steroids, tannins and triterpenes. Each studied plant extract was found to contain compounds belonging to at least two of the above mentioned classes. Conclusion These results confirm the traditional claims and provide promising baseline information for the potential use of the tested vegetables in the fight against bacterial infections involving MDR phenotypes. PMID:23368430

  3. 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

    Kaensombath, Lampheuy; Lindberg, Jan Erik

    2013-01-01

    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

  4. [Production of cassava whole meal (N. esculenta Crantz) to prepare a feed for growing chicks. I. Chemical and nutritive characterization of leaves, roots and cassava whole meal].

    PubMed

    Ballinas Díaz, J; Cruz Mondragón, C; Castellanos Molina, R; Larios Saldaña, A

    1997-12-01

    Cassava roots are frequently used as a energy source in feeds. The leaves due to their high fiber content, are not used in animal feeds despite they have a good content of protein and a balanced level of essential amino acids. The purpose of this research was to produce a cassava whole meal (CWF) with low content of fiber for using in chick feed. Leaves and roots of cassava by separated, were dried at 60 degrees C for 20 h, ground in a hammermill and passed through a 60 mesh sieve. By this procedure a root flour (CRF) and a leaves flour were obtained (CLF). The fiber content in CLF was reduced 25.8% and the protein content was increased 8.2%. The CWF was made with 61.2% of CRF and 38.8% of CLF, having a protein and fiber content of 9.15% and 9.73%, respectively. The True Metabolizable Energy of CWF was 2,454 kcal/kg with an average true bioavailability of amino acids of 68.8%. PMID:9673702

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

    PubMed Central

    Nauwelaerts, Sandra; Ramsay, Jason; Aerts, Peter

    2007-01-01

    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 intermediate phenotype that can perform both tasks reasonably well, but its performance will never match that of a specialized phenotype. We found no direct evidence for a trade-off between jumping and swimming performance nor for a coupled optimization. This could be due to the importance of overall quality, as suggested by the fact that some frogs possess greater overall muscularity than others, irrespective of their body size. Another explanation could be that some morphological characteristics have a positive effect on both locomotor modes and others show a trade-off effect. The net effect of these characteristics could result in an overall absence of correlation between the two locomotor performances. Size has a great influence on the morphological data and on jumping performance, but not if performance is expressed as velocity. The body shape of an anuran is conservative and scales mostly isometrically. PMID:17331179

  6. Essential and toxic metals in taros (Colocasia esculenta) cultivated in the Canary Islands (Spain): evaluation of content and estimate of daily intake.

    PubMed

    Luis-González, Gara; Rubio, Carmen; Gutiérrez, Ángel; González-Weller, Dailos; Revert, Consuelo; Hardisson, Arturo

    2015-01-01

    Taros are a staple in the diet of many people around the world, and they are an excellent source of minerals. Monitoring the levels of metals in food provides basic information that is useful from the perspectives of safety, regulation, and nutrition. Forty-two samples of taros were randomly obtained from supermarkets, vegetable markets, and farmer's plots on the island of Tenerife (Canary Islands, Spain). The edible portion (pulp) was the only part considered for analysis. Flame atomic absorption spectrometry (FAAS) was used to determine the contents of Na, K, Ca, Mg, Cu, Fe, Mn, and Zn. The levels of Cr, Ni, Cd, and Pb were determined using graphite furnace atomic absorption spectrometry (GFAAS). Mean concentrations (mg/kg) were 565.6 Na, 2947 K, 231.4 Ca, 364.5 Mg, 1.224 Cu, 3.818 Fe, 1.408 Mn, 2.242 Zn, 0.044 Cr, 0.021 Ni, 0.003 Cd, and 0.006 Pb. The mean concentrations of Cd and Pb were well below the accepted European Commission limits (0.1 mg/kg weight for both metals, respectively). Daily consumption of taro (10.41 g taro/person/day) contributes to the dietary intake of essential metals and trace elements, mainly Mg (1.265% in adult women and 1.084% in adult men) and Cu (1.182% for adult men and women). The average daily intakes of Cd (0.031 μg/day) and Pb (0.062 μg/day) from taro were below the legislated respective tolerable weekly intakes (TWIs). Thus, the samples analyzed were considered safe to eat based on their metal concentrations and legislated allowable intakes. PMID:25412891

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

    SciTech Connect

    Bernocchi, G.; Scherini, E.; Giacometti, S.; Mares, V. )

    1990-12-01

    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.

  8. Anti-Inflammatory Effect of 1,3,5,7-Tetrahydroxy-8-isoprenylxanthone Isolated from Twigs of Garcinia esculenta on Stimulated Macrophage

    PubMed Central

    Zhang, Dan-Dan; Zhang, Hong; Lao, Yuan-zhi; Wu, Rong; Xu, Jin-wen; Murad, Ferid; Bian, Ka; Xu, Hong-Xi

    2015-01-01

    Garcinia Linn. plants having rich natural xanthones and benzophenones with anti-inflammatory activity attracted a great deal of attention to discover and develop them as potential drug candidates. Through screening targeting nitric oxide accumulation in stimulated macrophage, we found that 1,3,5,7-tetrahydroxy-8-isoprenylxanthone (TIE) had potential anti-inflammatory effect. To understand how TIE elicits its anti-inflammatory activity, we uncovered that it significantly inhibits the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS/IFN?-stimulated RAW264.7 cells. In further study, we showed that TIE reduced the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), two key molecules responsible for the production of NO and PGE2 during inflammation progress. Additionally, TIE also suppressed the expression of inflammatory cytokines IL-6, IL-12, and TNF-?. TIE-led suppression in iNOS, COX-2, and cytokines production were probably the consequence of TIE's capability to block ERK and p38MAPK signaling pathway. Moreover, TIE blocked activation of nuclear factor-kappa B (NF-?B) as well as NF-?B regulation of miR155 expression. Our study suggests that TIE may represent as a potential therapeutic agent for the treatment of inflammatory diseases. PMID:26538826

  9. Prediction of gross energy and digestible energy in copra meal, palm kernel meal, and cassava root fed to pigs.

    PubMed

    Park, C S; Son, A R; Kim, B G

    2012-12-01

    Many of the available prediction equations for feed energy value may not be applicable for ingredients such as copra (Cocos nucifera) meal (CM), palm kernel meal (PKM), and cassava (Manihot esculenta) root (CR). Therefore, we developed novel equations for estimating GE and DE concentrations in CM, PKM, CR, and diets containing these ingredients. Data for GE and DE concentrations were obtained from previous experiments in which the chemical composition in the ingredients and diets were determined. In addition, in vitro DM digestibility (IVDMD) values in 3 samples of ingredients including CM, PKM, and CR and 4 samples of diets including a corn (Zea mays)-soybean (Glycine max) meal-based diet and 3 diets containing CM, PKM, and CR were determined. Based on the model R(2), conceptual predictive criterion, and the P-value of the equation, the best equation for GE concentration (kcal/kg) was GE = 3313 + (24.81 × CP) + (9.83 × NDF) with R(2) = 0.93, root mean square error = 102, and P = 0.005 (CP and NDF values are percentages). Regression analysis was conducted between the DE:GE ratio and IVDMD (%). The DE:GE ratio was 0.81, 0.73, 0.83, 0.89, 0.84, 0.82, and 0.88 in CM, PKM, CR, a corn-soybean meal-based diet, and diets containing CM, PKM, or CR, respectively. The values for IVDMD were 70.3, 42.6, 88.2, 93.4, 86.7, 75.5, and 91.3%, respectively. The DE:GE ratio may be calculated by (0.0030 × IVDMD) + 0.5986 (R(2) = 0.91; P = 0.001). Using the estimated GE concentration and IVDMD, the prediction equation for DE concentration (kcal/kg) was DE = -1965 + (1.02 × GE) + (15.33 × IVDMD) with R(2) = 0.88 and P = 0.007. In conclusion, IVDMD values are useful in estimating energy digestibility in CM, PKM, CR, and diets containing these ingredients. PMID:23365336

  10. Isolation and Characterization of Three Cassava Elongation Factor 1 Alpha (MeEF1A) Promoters

    PubMed Central

    Suhandono, Sony; Apriyanto, Ardha; Ihsani, Nisa

    2014-01-01

    In plant genetic engineering, the identification of gene promoters leading to particular expression patterns is crucial for the development of new genetically modified plant generations. This research was conducted in order to isolate and characterize several new promoters from cassava (Manihot esculenta Crantz) elongation factor 1 alpha (EF1A) gene family. Three promoters MeEF1A3, MeEF1A4 and MeEF1A5 were successfully isolated. Sequence analyses showed that all of the promoters contain three conserved putative cis-acting elements which are located upstream of the transcription start site. These elements are included a TEF1, a TELO and TATA boxes. In addition, all of the promoters also have the 5′UTR intron but with a different lengths. These promoters were constructed translationally with gusA reporter gene (promoter::gusA fusion) in pBI-121 binary vector to build a new binary vector using Overlap Extension PCR Cloning (OEPC) technique. Transient expression assay that was done by using agroinfiltration method was used to show functionality of these promoters. Qualitative and quantitative analysis from GUS assay showed that these promoters were functional and conferred a specific activity in tobacco seedlings (Nicotiana tabacum), tomato fruits (Solanum lycopersicum) and banana fruits (Musa acuminata). We hypothesized that MeEF1A6 could be categorized as a constitutive promoter because it was able to drive the gene expression in all transformed tissue described in here and also comparable to CaMV35S. On the other hand, MeEF1A3 drove specific expression in the aerial parts of seedlings such as hypocotyl and cotyledon thus MeEF1A5 drove specific expression in fruit tissue. The results obtained from transient analysis showed that these promoters had a distinct activity although they came from same gene family. The DNA sequences identified here are new promoters potentially use for genetic engineering in cassava or other plants. PMID:24404183

  11. Two Novel DNAs That Enhance Symptoms and Overcome CMD2 Resistance to Cassava Mosaic Disease

    PubMed Central

    De León, Leandro; Doyle, Catherine D.; Sseruwagi, Peter; Plata, German; Legg, James P.; Thompson, Graham; Tohme, Joe; Aveling, Theresa; Ascencio-Ibáñez, Jose T.

    2016-01-01

    ABSTRACT Cassava mosaic begomoviruses (CMBs) cause cassava mosaic disease (CMD) across Africa and the Indian subcontinent. Like all members of the geminivirus family, CMBs have small, circular single-stranded DNA genomes. We report here the discovery of two novel DNA sequences, designated SEGS-1 and SEGS-2 (for sequences enhancing geminivirus symptoms), that enhance symptoms and break resistance to CMD. The SEGS are characterized by GC-rich regions and the absence of long open reading frames. Both SEGS enhanced CMD symptoms in cassava (Manihot esculenta Crantz) when coinoculated with African cassava mosaic virus (ACMV), East African cassava mosaic Cameroon virus (EACMCV), or East African cassava mosaic virus-Uganda (EACMV-UG). SEGS-1 also overcame resistance of a cassava landrace carrying the CMD2 resistance locus when coinoculated with EACMV-UG. Episomal forms of both SEGS were detected in CMB-infected cassava but not in healthy cassava. SEGS-2 episomes were also found in virions and whiteflies. SEGS-1 has no homology to geminiviruses or their associated satellites, but the cassava genome contains a sequence that is 99% identical to full-length SEGS-1. The cassava genome also includes three sequences with 84 to 89% identity to SEGS-2 that together encompass all of SEGS-2 except for a 52-bp region, which includes the episomal junction and a 26-bp sequence related to alphasatellite replication origins. These results suggest that SEGS-1 is derived from the cassava genome and facilitates CMB infection as an integrated copy and/or an episome, while SEGS-2 was originally from the cassava genome but now is encapsidated into virions and transmitted as an episome by whiteflies. IMPORTANCE Cassava is a major crop in the developing world, with its production in Africa being second only to maize. CMD is one of the most important diseases of cassava and a serious constraint to production across Africa. CMD2 is a major CMD resistance locus that has been deployed in many cassava cultivars through large-scale breeding programs. In recent years, severe, atypical CMD symptoms have been observed occasionally on resistant cultivars, some of which carry the CMD2 locus, in African fields. In this report, we identified and characterized two DNA sequences, SEGS-1 and SEGS-2, which produce similar symptoms when coinoculated with cassava mosaic begomoviruses onto a susceptible cultivar or a CMD2-resistant landrace. The ability of SEGS-1 to overcome CMD2 resistance and the transmission of SEGS-2 by whiteflies has major implications for the long-term durability of CMD2 resistance and underscore the need for alternative sources of resistance in cassava. PMID:26865712

  12. Biosynthesis of the Cyanogenic Glucosides Linamarin and Lotaustralin in Cassava: Isolation, Biochemical Characterization, and Expression Pattern of CYP71E7, the Oxime-Metabolizing Cytochrome P450 Enzyme1[OA

    PubMed Central

    Jrgensen, Kirsten; Morant, Anne Vinther; Morant, Marc; Jensen, Niels Bjerg; Olsen, Carl Erik; Kannangara, Rubini; Motawia, Mohammed Saddik; Mller, Birger Lindberg; Bak, Sren

    2011-01-01

    Cassava (Manihot esculenta) is a eudicotyledonous plant that produces the valine- and isoleucine-derived cyanogenic glucosides linamarin and lotaustralin with the corresponding oximes and cyanohydrins as key intermediates. CYP79 enzymes catalyzing amino acid-to-oxime conversion in cyanogenic glucoside biosynthesis are known from several plants including cassava. The enzyme system converting oxime into cyanohydrin has previously only been identified in the monocotyledonous plant great millet (Sorghum bicolor). Using this great millet CYP71E1 sequence as a query in a Basic Local Alignment Search Tool-p search, a putative functional homolog that exhibited an approximately 50% amino acid sequence identity was found in cassava. The corresponding full-length cDNA clone was obtained from a plasmid library prepared from cassava shoot tips and was assigned CYP71E7. Heterologous expression of CYP71E7 in yeast afforded microsomes converting 2-methylpropanal oxime (valine-derived oxime) and 2-methylbutanal oxime (isoleucine-derived oxime) to the corresponding cyanohydrins, which dissociate into acetone and 2-butanone, respectively, and hydrogen cyanide. The volatile ketones were detected as 2.4-dinitrophenylhydrazone derivatives by liquid chromatography-mass spectrometry. A KS of approximately 0.9 ?m was determined for 2-methylbutanal oxime based on substrate-binding spectra. CYP71E7 exhibits low specificity for the side chain of the substrate and catalyzes the conversion of aliphatic and aromatic oximes with turnovers of approximately 21, 17, 8, and 1 min?1 for the oximes derived from valine, isoleucine, tyrosine, and phenylalanine, respectively. A second paralog of CYP71E7 was identified by database searches and showed approximately 90% amino acid sequence identity. In tube in situ polymerase chain reaction showed that in nearly unfolded leaves, the CYP71E7 paralogs are preferentially expressed in specific cells in the endodermis and in most cells in the first cortex cell layer. In fully unfolded leaves, the expression is pronounced in the cortex cell layer just beside the epidermis and in specific cells in the vascular tissue cortex cells. Thus, the transcripts of the CYP71E7 paralogs colocalize with CYP79D1 and CYP79D2. We conclude that CYP71E7 is the oxime-metabolizing enzyme in cyanogenic glucoside biosynthesis in cassava. PMID:21045121

  13. Feeding and lying behavior of heat-stressed early lactation cows fed low fiber diets containing roughage and nonforage fiber sources.

    PubMed

    Kanjanapruthipong, J; Junlapho, W; Karnjanasirm, K

    2015-02-01

    In addition to reduced nutrient intake, an environmental thermal load may directly affect milk yield in heat-stressed dairy cows. Feeding and lying behaviors of early lactation cows fed low fiber diets containing neutral detergent fiber (NDF) from roughage and nonforage fiber sources (NFFS) were investigated under summer conditions in Thailand. Immediately after calving, 30 multiparous cows (87.5% Holstein × 12.5% Sahiwal) were randomly allocated to dietary treatments for 63 d in a completely randomized design. The dietary treatments contained 25% of dry matter (DM) as dietary NDF. The control diet consisted of 13.9% roughage NDF from rice straw (RS). Two additional treatments were created by replacing 3.9% of DM with NDF from either soy hulls (SH) or cassava (Manihot esculenta Grantz) residues (CR), so that the roughage NDF content was reduced to 10%. During the experimental period, the minimum and maximum temperature-humidity indices (THI) were 86.4±2.5 and 91.5±2.7 during the day and 74.2±2.1 and 81.0±2.5 during the night, respectively, indicating conditions appropriate for induction of extreme heat stress. The duration of feeding and lying bouts decreased linearly with increasing THI. The DM intake during the day was greater for cows fed diets containing SH and CR than for those fed the diet containing NDF from RS. The number of meals during the day and night was lower, whereas meal size and meal length during the day and night were greater for cows fed diets containing SH and CR. Cows fed diets containing SH and CR lay down less frequently and longer during the day. These results suggest that under the severe heat stress during the day, early lactation cows fed the diet containing NFFS increased DM intake by increasing meal length and meal size rather than by increasing meal frequency and they spent more time lying. Cows fed diets containing NDF from SH and CR produced more 4% fat-corrected milk, lost less body weight, and had lower rectal temperatures measured at the 1530h milking. Therefore, reducing the filling effect may contribute to reducing heat load derived from the change in feeding and lying behavior. This should be considered as a factor for impairing productivity of heat-stressed early lactation cows. PMID:25497805

  14. Heartbeat Registration Experiment (Rana Esculenta): Demonstration of the Preparatory Phase. A Case Study in the Design of a Video Presentation for Use in the Physiology Laboratory in the Department of Comparative Physiology at the Rijksuniversiteit Utrecht, Utrecht, the Netherlands.

    ERIC Educational Resources Information Center

    Earl, F. A.

    This case study describes the design of a video tape presentation for use in a college physiology laboratory. A goal of this color film is to demonstrate to the students those techniques involved in anaesthetising and preparing a frog for a laboratory experiment on the reaction of the heart to electrical and chemical stimuli. The film first shows

  15. Heartbeat Registration Experiment (Rana Esculenta): Demonstration of the Preparatory Phase. A Case Study in the Design of a Video Presentation for Use in the Physiology Laboratory in the Department of Comparative Physiology at the Rijksuniversiteit Utrecht, Utrecht, the Netherlands.

    ERIC Educational Resources Information Center

    Earl, F. A.

    This case study describes the design of a video tape presentation for use in a college physiology laboratory. A goal of this color film is to demonstrate to the students those techniques involved in anaesthetising and preparing a frog for a laboratory experiment on the reaction of the heart to electrical and chemical stimuli. The film first shows…

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

    PubMed

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

    2011-11-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

    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.

  18. Molecular characterization of Dasheen mosaic virus isolates infecting edible aroids in India.

    PubMed

    Babu, B; Hegde, V

    2014-01-01

    Dasheen mosaic virus (DsMV) infecting three major edible aroids namely Amorphophallus paeoniifolius, Colocasia esculenta, and Xanthosoma sagittifolium cultivated in India was characterized. Infected plants showing typical DsMV symptoms were subjected to reverse transcription-polymerase chain reaction, and an amplification of a 963 bp fragment which encoded the coat protein (CP) gene was obtained. BLAST analysis of the cloned DNA amplicon revealed the identity of the virus to be that of DsMV. Sequence identity matrix of the nucleotide sequences among the three isolates showed that the DsMV isolate infecting A. paeoniifolius and C. esculenta shared an identity as high as 93%, while the DsMV isolate from X. sagittifolium shared an identity of only 73% and 76% with the DsMV isolates from A. paeoniifolius and C. esculenta, respectively. Comparative analysis of the coat protein of the three DsMV isolates showed the presence of DVG motif (A. paeoniifolius and C. esculenta) and DTG motif in X. sagittifolium and several varying potential threonine and asparagine rich N-glycosylation motifs. Single amino acid substitution of the several conserved motifs occurs in all the three DsMV isolates. This is the first characterization of DsMV isolates infecting A. paeoniifolius, C. esculenta, and X. sagittifolium plants in India. PMID:24717027

  19. Atomic force microscopy and thermodynamics on taro, a self-cleaning plant leaf

    NASA Astrophysics Data System (ADS)

    Hüger, E.; Rothe, H.; Frant, M.; Grohmann, S.; Hildebrand, G.; Liefeith, K.

    2009-07-01

    The evolution-optimized leaves of Colocasia esculenta (taro) and Nelumbo nucifera (lotus) are the best optimized self-cleaning surfaces known to date. Using an atomic force microscope device equipped with a piezodriven sample stage which enables a z-range of 100 μm we measured the surface morphology of dried and undried leaves of Colocasia esculenta. Thermodynamic calculations were done to investigate the interaction strength of a water droplet with the surfaces of the morphology shown in the images. The results show that the hierarchical structure produces a stable superhydrophobic state with optimal self-cleaning properties.

  20. 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...

  1. High-resolution mapping of resistance to cassava mosaic geminiviruses in cassava using genotyping-by-sequencing and its implications for breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cassava mosaic disease (CMD), caused by different species of cassava mosaic geminiviruses (CMGs), is the most important disease of cassava in Africa and the Indian sub-continent. The cultivated cassava species is protected from CMD by polygenic resistance introgressed from the wild species Manihot g...

  2. 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...

  3. Mapping Wild Taro with Color-infrared Aerial Photography and Image Processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild taro [Colocasia esculenta (L.) Schott.] is an exotic ornamental plant that has escaped cultivation and invaded many freshwater wetlands in the southeastern United States. Remote sensing techniques were evaluated for distinguishing wild taro along the Rio Grande in southwest Texas. Field refle...

  4. Geology and geochemistry of newly discovered Tertiary carbonatite occurrences near Villa Ahumada area, Basin and Range province, Chihuahua, northern Mexico

    NASA Astrophysics Data System (ADS)

    Nandigam, Ravi Chenchu

    This study targets some newly discovered carbonatite occurrences located in the eastern Mexican Basin and Range province, a few kilometers to the east of Villa Ahumada, Chihuahua. The region containing these occurrences experienced compression related to subduction of the Farallon plate until about 32 Ma that was followed by Basin and Range extension. Geological mapping (1:5,000 scale), petrography, study of drill hole cuttings and satellite images, and major and trace element chemical analyses were utilized to understand the intrusive style of the carbonatites, their mineralogy and petrogenesis. The carbonatites, named Yuca, Mariana and El Indio, collectively intrude limestones, granitic intrusives and subduction-related tuffs and lavas mainly as a stock, breccias and dikes. The Yuca carbonatite was emplaced as a 900-m diameter stock, 500 x 350 m breccia body, numerous dikes and networks of fracture fillings. Crosscutting field relationships at Yuca suggest at least two stages of carbonatite emplacement. At Mariana, carbonatite was emplaced as a 750 x 350 m breccia. Four out of nine reverse circulation drill holes penetrated and bottomed in the breccia at an average depth of about 300 m At El Indio, carbonatite was emplaced as a 20 m diameter breccia pipe and a 1m thick sill. Major minerals present are calcite, Fe-rich calcite and hematite. Sporadic presence of fluorite is common. At Mariana, two generations of grossular-rich garnets associated with limestones and granite porphyry respectively are recognized. It is inferred that garnets in granite porphyry represent metasomatic alteration due to the emplacement of carbonatite breccia. Parental magmas of Yuca carbonatites have undergone differentiation under low fO2 conditions during which they were progressively enriched in iron. The carbonatite compositional types recognized based on major element data, in the sequence of least to most highly differentiated, are (1) magnesio-, (2) calcio- and (3) ferrocarbonatites. The concentrations of thorium, uranium, niobium, yttrium and rare earth elements increase with differentiation. Carbonatites are associated with up to 20000 times enrichment of lanthanum and cerium with respect to chondrite. Finally, the Mariana carbonatite breccia is associated with about 7,928,550 short tons of rock with a grade of 0.14% SigmaREE, and primitive mantle normalized trace element plots of carbonatites indicate a mantle origin of their parental melts.

  5. CuI-semiquinone radical species in plant copper-amine oxidases.

    PubMed

    Medda, R; Padiglia, A; Bellelli, A; Pedersen, J Z; Agrò, A F; Floris, G

    1999-06-18

    The intermediate CuI-semiquinone radical species in the catalytic mechanism of copper-amine oxidase from Lens esculenta and Pisum sativum seedlings has been studied by optical, Raman resonance and ESR spectroscopies and by stopped-flow and temperature-jump measurements. Treatment of highly purified enzyme preparations with good, poor or suicide substrates, under anaerobic and aerobic conditions, at different pH values and temperatures, makes it possible to generate, detect and characterize this free radical intermediate. PMID:10403363

  6. [A molecular hybrid having gonadotropic activity in frogs composed of the alpha subunit of bovine luteinizing hormone and a subunit of a gonadotropin of a teleost fish].

    PubMed

    Fontaine, M M

    1976-01-01

    The alpha subunit of bovine LH and the subunit SU II of carp gonadotropin are able to associate. The hybrid is about one hundred times less active than c-GTH or b-LH, respectively on goldfish and rat ovarian adenyl cyclase. However it is more efficient than both horomones on an Amphibian (Rana esculenta), on spermiation in vivo as well as on ovarian adenyl cyclase in vitro. PMID:816536

  7. Phylogeny of Morella rubra and Its Relatives (Myricaceae) and Genetic Resources of Chinese Bayberry Using RAD Sequencing.

    PubMed

    Liu, Luxian; Jin, Xinjie; Chen, Nan; Li, Xian; Li, Pan; Fu, Chengxin

    2015-01-01

    Phylogenetic relationships among Chinese species of Morella (Myricaceae) are unresolved. Here, we use restriction site-associated DNA sequencing (RAD-seq) to identify candidate loci that will help in determining phylogenetic relationships among Morella rubra, M. adenophora, M. nana and M. esculenta. Three methods for inferring phylogeny, maximum parsimony (MP), maximum likelihood (ML) and Bayesian concordance, were applied to data sets including as many as 4253 RAD loci with 8360 parsimony informative variable sites. All three methods significantly favored the topology of (((M. rubra, M. adenophora), M. nana), M. esculenta). Two species from North America (M. cerifera and M. pensylvanica) were placed as sister to the four Chinese species. According to BEAST analysis, we deduced speciation of M. rubra to be at about the Miocene-Pliocene boundary (5.28 Ma). Intraspecific divergence in M. rubra occurred in the late Pliocene (3.39 Ma). From pooled data, we assembled 29378, 21902 and 23552 de novo contigs with an average length of 229, 234 and 234 bp for M. rubra, M. nana and M. esculenta respectively. The contigs were used to investigate functional classification of RAD tags in a BLASTX search. Additionally, we identified 3808 unlinked SNP sites across the four populations of M. rubra and discovered genes associated with fruit ripening and senescence, fruit quality and disease/defense metabolism based on KEGG database. PMID:26431030

  8. Phylogeny of Morella rubra and Its Relatives (Myricaceae) and Genetic Resources of Chinese Bayberry Using RAD Sequencing

    PubMed Central

    Liu, Luxian; Jin, Xinjie; Chen, Nan; Li, Xian; Li, Pan; Fu, Chengxin

    2015-01-01

    Phylogenetic relationships among Chinese species of Morella (Myricaceae) are unresolved. Here, we use restriction site-associated DNA sequencing (RAD-seq) to identify candidate loci that will help in determining phylogenetic relationships among Morella rubra, M. adenophora, M. nana and M. esculenta. Three methods for inferring phylogeny, maximum parsimony (MP), maximum likelihood (ML) and Bayesian concordance, were applied to data sets including as many as 4253 RAD loci with 8360 parsimony informative variable sites. All three methods significantly favored the topology of (((M. rubra, M. adenophora), M. nana), M. esculenta). Two species from North America (M. cerifera and M. pensylvanica) were placed as sister to the four Chinese species. According to BEAST analysis, we deduced speciation of M. rubra to be at about the Miocene-Pliocene boundary (5.28 Ma). Intraspecific divergence in M. rubra occurred in the late Pliocene (3.39 Ma). From pooled data, we assembled 29378, 21902 and 23552 de novo contigs with an average length of 229, 234 and 234 bp for M. rubra, M. nana and M. esculenta respectively. The contigs were used to investigate functional classification of RAD tags in a BLASTX search. Additionally, we identified 3808 unlinked SNP sites across the four populations of M. rubra and discovered genes associated with fruit ripening and senescence, fruit quality and disease/defense metabolism based on KEGG database. PMID:26431030

  9. Removal of furanocoumarins in grapefruit juice by edible fungi.

    PubMed

    Myung, Kyung; Narciso, Jan A; Manthey, John A

    2008-12-24

    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

  10. Evaluation of phytochemical constituents and antioxidant activity of selected actinorhizal fruits growing in the forests of Northeast India.

    PubMed

    Goyal, Arvind K; Mishra, Tanmayee; Bhattacharya, Malay; Kar, Pallab; Sen, Arnab

    2013-11-01

    Hippophae salicifolia, Elaeagnus pyriformis, Myrica esculenta and M. nagi are actinorhizal plants growing in the sacred forests of Northeast India with multipurpose uses. The present investigation was undertaken to determine the phenol, flavonoid and flavonol contents of the fresh fruit juice of these plant species including the antioxidant potential by means of DPPH, H2O2 and NO scavenging activity and FRP. The total phenolic, flavonoid and flavonol contents of fruit juice ranged from 321.68+/-0.06 to 76.67+/-0.01 mg/g GAE, 272.92+/-0.07 to 20.12+/-0.02 mg/g QE and 258.92+/-0.08 to 18.72+/-0.02 mg/g QE, respectively. At 2.0 mg/mL concentration, DPPH scavenging activity was found to be the highest in M. esculenta (89.62 percent) and the lowest in E. pyriformis (17.58 percent). The reducing power activity was found significantly higher in H. salicifolia juice, which increased with increase in concentration. The H2O2 scavenging activity of H. salicifolia juice was found to be as high as 98.78 percent, while Elaeagnus juice was found to be less effective with just 48.90 percent. Juice of H. salicifolia showed the greatest NO scavenging effect of 75.24 percent as compared to juice of E. pyriformis, where only 37.54 percent scavenging was observed at the same concentration. Taking into account all the experimental data, it can be said that the fruits of H. salicifolia and both M. nagi and M. esculenta have good antioxidant activity compared to fruits of E. pyriformis. PMID:24287659

  11. Bound potassium in muscle II.

    PubMed

    Hummel, Z

    1980-01-01

    Experiments were performed to decide between the alternatives a) the ionized K+ is in a dissolved state in the muscle water, or b) a part of the muscle potassium is in a "bound' state. Sartorius muscles of Rana esculenta were put into glicerol for about one hour at 0-2 degrees C. Most of muscle water came out, but most of muscle potassium remained in the muscles. In contrast to this: from muscle in heat rigor more potassium was released due to glicerol treating than from the intact ones. 1. Supposition a) is experimentally refuted. 2. Supposition b) corresponds to the experimental results. PMID:6969511

  12. EPR investigation of some desiccated Ascomycota and Basidiomycota gamma-irradiated mushrooms

    NASA Astrophysics Data System (ADS)

    Bercu, V.; Negut, C. D.; Duliu, O. G.

    2010-12-01

    The suitability of the EPR spectroscopy for detection of γ-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.

  13. Level of heavy metals in some edible and poisonous macrofungi from Batman of South East Anatolia, Turkey.

    PubMed

    Yesil, Omer Faruk; Yildiz, Abdunnasir; Yavuz, Omer

    2004-07-01

    The macrofungi specimens were collected and identified from locations around Batman province of Turkey. A group of 21 macrofungi were collected from 29 different locations and analysed for the heavy metal contents. The highest Pb and Cu levels were found in Russula rubroalba while the highest Cd level was determined for the species Agaricus xanthodermus. Fe level was maximum for the species Funalia trogii; Mn for Mycena personsii; Zn level was for Morchella esculenta and Co level was for the species Agaricus xanthodermus. The lowest Cd, Cu, Mn and Zn contents were found in Inotus hispidus. PMID:15847333

  14. The large bowel carcinogenic effects of hydrazines and related compounds occurring in nature and in the environment.

    PubMed

    Toth, B

    1977-11-01

    Five substituted hydrazines that induce large bowel and other types of cancer in laboratory animals are described. Two of these compounds, which originate in nature, are 1,1-dimethylhydrazine, a tobacco ingredient, and methylhydrazine, formed from a chemical present in the edible wild mushroom Gyromitra esculenta. The human population is therefore exposed to them considerably. In addition, both compounds are manufactured and used in rocket fuel. The other three chemicals, 1,2-dimethylhydrazine dihydrochloride,1-methyl-2-butylhydrazine dihydrochloride and trimethylhydrazine hydrochloride, are manufactured synthetically only and apparently are not found in substantial quantities in the environment. PMID:922685

  15. Selected emerging diseases of amphibia.

    PubMed

    Latney, La'Toya V; Klaphake, Eric

    2013-05-01

    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

  16. Endocannabinoids and Endovanilloids: A Possible Balance in the Regulation of the Testicular GnRH Signalling

    PubMed Central

    Ciaramella, Vincenza; Scarpa, Donatella; Fasano, Silvia; Pierantoni, Riccardo

    2013-01-01

    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. PMID:24072997

  17. Evaluation of the Antioxidant Activities and Tyrosinase Inhibitory Property from Mycelium Culture Extracts

    PubMed Central

    Park, Ki Moon; Kwon, Kyung Min; Lee, Seung Ho

    2015-01-01

    Since mushrooms have many bioactive components, they have been used as components in folk medicine. Because mycelium has an advantage when it comes to large-scale production, this study aimed to evaluate the antioxidant properties and anti-tyrosinase activity from 55 mycelia in culture media. Relatively high 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity was detected from the ethanol extract of culture media including mycelium (EECiM) of Morchella esculenta var. esculenta (MEVE), Auricularia polytricha (APO), Tremella aurantia (TAU), Volvariella bombycina (VBO), and Oudemansiella sp. (Osp), which also showed strong reducing power and inhibitory activity in relation to the thiobarbituric acid (TBA) value. On the other hand, relatively high tyrosinase inhibitory activity was detected in Inonotus mikadoi (IMI), Coriolus versicolor (CVE), Volvariella volvacea (VVO), Panellus serotinus (PSE), Auricularia auricula (AAU), and Fomitopsis sp. (Fsp). Interestingly, the APO EECiM exhibited the highest DPPH radical scavenging rate (77.5 ± 4.3%) and reducing power (1.18 ± 0.041), while the highest inhibitory power of the TBA value and antityrosinase activity were detected in that of TAU (64.5 ± 4.1%) and IMI (46.0 ± 7.5%), respectively. Overall, our study suggested potential candidates for EECiMs that exhibited powerful antioxidant and tyrosinase inhibitory properties and might be used as natural antioxidant tyrosinase inhibitor. PMID:26345142

  18. Studies on some edible wild mushrooms from Nigeria: 1. Nutritional, teratogenic and toxic considerations.

    PubMed

    Adewusi, S R; Alofe, F V; Odeyemi, O; Afolabi, O A; Oke, O L

    1993-03-01

    The biological value of 5 mushrooms Chlorophyllum molybditis, Psathyrella atroumbonata, Termitomyces robustus, Termitomyces striatus and Volvariella esculenta from our collection of wild edible mushrooms were determined using weanling rats. C. molybditis supported rapid growth with PER (2.63) higher than the casein control (2.50). P. atroumbonata was average in biological performance (PER 1.50) while T. robustus and V. esculenta did not support growth at all. Rats on T. striatus dried at 60 degrees C for 48 h lost weight rapidly and showed pathological signs of toxicity by the second day. All rats on this diet died by the fourth day of the experiment. When the diet of T. striatus dried at 90 degrees C for about 8 h was fed, the rats gained weight marginally but all survived. Prolonged storage of T. striatus at 60 degrees C for 5-8 weeks also seemed to detoxify the poisonous component such that PER and NPR values were 0.8 and 2.0 respectively. 2 pairs each of adult rats fed C. molybditis and Tricholoma lobayensis diets for 10 days were mated. Rats of C. molybditis diet gave 5 and 6 litters each and only one of these litters seemed to have retarded growth. Rats on T. lobayensis diet did not produce any litters for 14 weeks but the female produced off-spring when mated with control male rats. PMID:8474999

  19. Spatial and temporal patterns of morel fruiting.

    PubMed

    Mihail, Jeanne D; Bruhn, Johann N; Bonello, Pierluigi

    2007-03-01

    The biotic and abiotic factors conditioning morel fruit body production are incompletely known. We examined spatial and temporal patterns of Morchella esculenta fruiting over five years in a wooded site in Missouri, USA. Fruiting onset was inversely correlated with spring air and soil temperatures, whereas abundance was positively correlated with rain events (>10mm) during the 30 d preceding fruiting. The two years with the greatest fruiting had the shortest fruiting seasons (6-7d). Fruiting season length was positively correlated with soil warming, suggesting that a narrow range of optimum soil temperatures favour the explosive production of fruit bodies. All woody stems of at least 1cm diam were mapped and stem diameter and crown condition were noted. Morel fruit bodies were significantly closer to stems of Carya spp., Tilia americana and Ulmus americana than predicted by the frequencies of these woody species or their contribution to the total basal area on the site. Although intra-annual clustering of fruit bodies was often observed, inter-annual clustering was not. The spatial pattern of M. esculenta fruiting appears to be associated with vegetation pattern, whereas the onset and abundance of fruiting are determined by the interaction of spring temperatures with availability of supporting precipitation. PMID:17363234

  20. Yams (Dioscorea spp.) from the South Pacific Islands contain many novel badnaviruses: implications for international movement of yam germplasm.

    PubMed

    Kenyon, Lawrence; Lebas, B S M; Seal, S E

    2008-01-01

    Yam (Dioscorea spp.) samples (n = 690) from seven South Pacific Islands were screened for badnavirus infection by ELISA using two antisera to African badnaviruses. Positive readings were obtained for 26.4-34.6% of samples representing both known (D. bulbifera, D. nummularia and D. pentaphylla) and unreported host species (D. alata, D. esculenta, D. rotundata and D. trifida) in this region. Total DNAs were extracted from 25 ELISA-positive plants and 4 ELISA-negative controls and subjected to PCR amplification with badnavirus-specific primers targeting the reverse transcriptase (RT)-RNaseH genes. All 29 samples yielded the expected size PCR-product for badnaviruses, which were cloned and sequenced. Phylogenetic analyses of the resulting 45 partial (500-527 bp) RT-RNaseH sequences revealed 11 new sequence groups with <79% nucleotide identity to each other or any EMBL sequence. Three sequences (two groups) were highly divergent to the other nine new South Pacific yam badnavirus groups (47.9-57.2% identity) and probably represent either new Caulimoviridae genera or endogenous pararetrovirus sequences. Some sequence groups appeared specific to particular Dioscorea host species. Four 99.9% identical RT-RNaseH sequences possessing nine amino acid deletions from D. esculenta from three islands represent a putative integrated sequence group. The distribution of sequence groups across the islands indicates that badnaviruses have spread extensively between islands and continents through infected germplasm. PMID:18330495

  1. Evaluation of the Antioxidant Activities and Tyrosinase Inhibitory Property from Mycelium Culture Extracts.

    PubMed

    Park, Ki Moon; Kwon, Kyung Min; Lee, Seung Ho

    2015-01-01

    Since mushrooms have many bioactive components, they have been used as components in folk medicine. Because mycelium has an advantage when it comes to large-scale production, this study aimed to evaluate the antioxidant properties and anti-tyrosinase activity from 55 mycelia in culture media. Relatively high 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity was detected from the ethanol extract of culture media including mycelium (EECiM) of Morchella esculenta var. esculenta (MEVE), Auricularia polytricha (APO), Tremella aurantia (TAU), Volvariella bombycina (VBO), and Oudemansiella sp. (Osp), which also showed strong reducing power and inhibitory activity in relation to the thiobarbituric acid (TBA) value. On the other hand, relatively high tyrosinase inhibitory activity was detected in Inonotus mikadoi (IMI), Coriolus versicolor (CVE), Volvariella volvacea (VVO), Panellus serotinus (PSE), Auricularia auricula (AAU), and Fomitopsis sp. (Fsp). Interestingly, the APO EECiM exhibited the highest DPPH radical scavenging rate (77.5 ± 4.3%) and reducing power (1.18 ± 0.041), while the highest inhibitory power of the TBA value and antityrosinase activity were detected in that of TAU (64.5 ± 4.1%) and IMI (46.0 ± 7.5%), respectively. Overall, our study suggested potential candidates for EECiMs that exhibited powerful antioxidant and tyrosinase inhibitory properties and might be used as natural antioxidant tyrosinase inhibitor. PMID:26345142

  2. Cancer induction in mice with acetaldehyde methylformylhydrazone of the false morel mushroom.

    PubMed

    Toth, B; Smith, J W; Patil, K D

    1981-10-01

    Acetaldehyde methylformylhydrazone (AMFH), which occurs up to 0.3% in one of the edible false morel mushrooms, Gyromitra esculenta, was administered to noninbred Swiss mice in propylene glycol in 52 weekly intragastric instillations as 100 micrograms/g body weight. The treatment induced tumors of the lungs, preputial glands, forestomach, and clitoral glands. The tumor incidences in these four tissues in treated females were 70, 0, 16, and 12%, respectively, whereas in the treated males they were 40, 90, 0, and 0%. The corresponding tumor incidences in the solvent control females were 26, 0, 0, and 0%, whereas in the solvent control males they were 22, 0, 0, and 0%, respectively. Histopathologically, the neoplasms were classified as adenomas and adenocarcinomas of the lungs; squamous cell papillomas and carcinomas, adenocarcinomas, undifferentiated carcinomas, angiosarcomas, and fibrosarcomas of the preputial glands; squamous cell papillomas and carcinomas of the forestomach; and squamous cell papillomas and carcinomas and keratoacanthomas of the clitoral glands. The study thus proves for the first time the tumorigenicity of AMFH. In view of these and earlier findings, the human population should abstain from consumption of Gyromitra esculenta. PMID:6944556

  3. Nutritional values and antioxidant potential of some edible mushrooms of Kashmir valley.

    PubMed

    Boda, Rouf Hamza; Wani, Abdul Hamid; Zargar, Mohammad Afzal; Ganie, Bashir Ahmad; Wani, Bilal Ahmad; Ganie, Showkat Ahmad

    2012-07-01

    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

  4. The complete chloroplast genome sequence of Euonymus japonicus (Celastraceae).

    PubMed

    Choi, Kyoung Su; Park, SeonJoo

    2016-09-01

    The complete chloroplast (cp) genome sequence of the Euonymus japonicus, the first sequenced of the genus Euonymus, was reported in this study. The total length was 157 637 bp, containing a pair of 26 678 bp inverted repeat region (IR), which were separated by small single copy (SSC) region and large single copy (LSC) region of 18 340 bp and 85 941 bp, respectively. This genome contains 107 unique genes, including 74 coding genes, four rRNA genes, and 29 tRNA genes. Seventeen genes contain intron of E. japonicus, of which three genes (clpP, ycf3, and rps12) include two introns. The maximum likelihood (ML) phylogenetic analysis revealed that E. japonicus was closely related to Manihot and Populus. PMID:26407184

  5. Origin and environmental setting of ancient agriculture in the lowlands of Mesoamerica.

    PubMed

    Pope, K O; Pohl, M E; Jones, J G; Lentz, D L; von Nagy, C; Vega, F J; Quitmyer, I R

    2001-05-18

    Archaeological research in the Gulf Coast of Tabasco reveals the earliest record of maize cultivation in Mexico. The first farmers settled along beach ridges and lagoons of the Grijalva River delta. Pollen from cultivated Zea appears with evidence of forest clearing about 5100 calendar years B.C. (yr B.C.) [6200 (14)C years before the present (yr B.P.)]. Large Zea sp. pollen, typical of domesticated maize (Zea mays), appears about 5000 calendar yr B.C. (6000 yr B.P.). A Manihot sp. pollen grain dated to 4600 calendar yr B.C. (5800 yr B.P.) may be from domesticated manioc. About 2500 calendar yr B.C. (4000 yr B.P.), domesticated sunflower seeds and cotton pollen appear as farming expanded. PMID:11359011

  6. Complete mitochondrial genome of Sipunculus nudus (Sipuncula, Sipunculidae).

    PubMed

    Song, Su-Xia; Ding, Shao-Xiong; Yan, Qing-Pi; Qin, Ying-Xue

    2016-03-01

    In this paper, the complete mitochondrial (mt) genome of Sipunculus nudus collected from the coast of southeast China was determined. The complete mt genome was 15,376?bp in length, including 13 protein-coding genes, 2 rRNA genes, 23 tRNA genes, and a putative control region (CR). The overall base composition of the H-strand is 29.25% A, 28.78% T, 27.19% C, and 14.78% G, with an AT content of 58.03%. The mt DNA of Chinese S. nudus shared 73.6% and 60.2% identities with that of French S. nudus (GenBank accession number: FJ42,2961) and Chinese Phascolosoma esculenta (GenBank accession number: EF58,3817), respectively. PMID:24938083

  7. Metal concentrations of wild edible mushrooms from Turkey.

    PubMed

    Sarikurkcu, Cengiz; Tepe, Bektas; Solak, Mehmet Halil; Cetinkaya, Serap

    2012-01-01

    In the present study, the contents of Zn, Fe, Cu, Mn, Co, Ni, Pb, Cd, Cr, Al, Ca, Mg, and K in Agaricus campestris, Agrocybe cylindracea, Collybia dryophila, Helvella leucopus, Russula delica, Tricholoma auratum, Amanita ovoidea, Melanoleuca excissa, Rhizopogon roseolus, Russula chloroides, Volvoriella gloiocephala, Lyophyllum decastes, Morcella angusticeps, Morchella esculenta and Morcella eximia collected from Isparta, Mugla, and Osmaniye provinces (Turkey) were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) after microwave digestion. The intake of heavy metals (Pb, Cd) and other metals (Fe, Cu, Zn) by consumption of 30 g dry weight of mushrooms daily poses no risk at all except in A. cylindracea and H. leucopus (for Cd) for the consumer. PMID:22794131

  8. Complete genome sequence of Colocasia bobone disease-associated virus, a putative cytorhabdovirus infecting taro.

    PubMed

    Higgins, Colleen M; Bejerman, Nicolas; Li, Ming; James, Anthony P; Dietzgen, Ralf G; Pearson, Michael N; Revill, Peter A; Harding, Robert M

    2016-03-01

    We report the first genome sequence of a Colocasia bobone disease-associated virus (CBDaV) derived from bobone-affected taro [Colocasia esculenta L. Schott] from Solomon Islands. The negative-strand RNA genome is 12,193 nt long, with six major open reading frames (ORFs) with the arrangement 3'-N-P-P3-M-G-L-5'. Typical of all rhabdoviruses, the 3' leader and 5' trailer sequences show complementarity to each other. Phylogenetic analysis indicated that CBDaV is a member of the genus Cytorhabdovirus, supporting previous reports of virus particles within the cytoplasm of bobone-infected taro cells. The availability of the CBDaV genome sequence now makes it possible to assess the role of this virus in bobone, and possibly alomae disease of taro and confirm that this sequence is that of Colocasia bobone disease virus (CBDV). PMID:26687584

  9. Permanent genetic resources added to Molecular Ecology Resources Database 1 October 2010-30 November 2010.

    PubMed

    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

    2011-03-01

    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

  10. Bacterial communities of two parthenogenetic aphid species cocolonizing two host plants across the Hawaiian Islands.

    PubMed

    Jones, Ryan T; Bressan, Alberto; Greenwell, April M; Fierer, Noah

    2011-12-01

    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. PMID:21965398

  11. Bacterial Communities of Two Parthenogenetic Aphid Species Cocolonizing Two Host Plants across the Hawaiian Islands ▿

    PubMed Central

    Jones, Ryan T.; Bressan, Alberto; Greenwell, April M.; Fierer, Noah

    2011-01-01

    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. PMID:21965398

  12. Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro

    SciTech Connect

    Benyhe, S.; Hoffman, G.; Varga, E.; Hosztafi, S.; Toth, G.; Borsodi, A.; Wollemann, M.

    1989-01-01

    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.

  13. Morama bean research in Texas: a technical report

    SciTech Connect

    Bousquet, J.E.

    1982-07-01

    The search for drought-resistant crops has energy-saving as well as water-saving goals. The agricultural potential of morama beans (Bauhinea esculenta, also known as Tylosema esculentum), a plant that grows extensively across southern Africa was investigated. The beans are usually eaten roasted, like peanuts. Morama tubers, which store water to assure the plant's survival in drought years, may be uprooted and eaten as a source of moisture and some other nutrients. The goals of the morama project were specifically to discover the tolerance of morama for Texas agronomic conditions, to discover the ideal conditions and methods of cultivation, to demonstrate the productivity and forage potential of the plants grown at various sites in Texas, and to measure the nutritional quality of the edible parts of this plant.

  14. Aquatic Plant/microbial Filters for Treating Septic Tank Effluent

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1988-01-01

    The use of natural biological processes for treating many types of wastewater have been developed by NASA at the John C. Stennis Space Center, NSTL, Mississippi, during the past 15 years. The simplest form of this technology involves the use of aquatic plant/marsh filters for treatment of septic tank effluent. Septic tank effluent from single home units can be treated to advanced secondary levels and beyond by using a 37.2 sq m (400 sq ft) surface area washed gravel filter. This filter is generally 0.3 m (1 ft) deep with a surface cover of approximately 0.15 m (6 in.) of gravel. The plants in this filter are usually aesthetic or ornamental such as calla lily (Zantedeschia aethiopica), canna lily (Canna flaccida), elephant ear (Colocasia esculenta), and water iris (Iris pseudacorus).

  15. Gyromitrin as a tumor inducer.

    PubMed

    Toth, B; Patil, K

    1981-01-01

    Acetaldehyde methylformylhydrazone (gyromitrin) was administered in propylene glycol as 12 weekly subcutaneous injections of 50 micrograms/g weight to randomly bred Swiss mice. The treatment induced lung and preputial gland tumors in incidences of 51 and 0% in females and 46 and 28% in males, respectively. In the propylene glycol injected control groups, the corresponding tumor incidences were 28 and 0% in females and 32 and 0% in males. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs and squamous cell papillomas and carcinomas and adenocarcinomas of preputial glands. Gyromitrin is an ingredient of the wild edible false morel mushroom Gyromitrin esculenta. The environmental significance of the findings is discussed. PMID:7198186

  16. Mercury uptake and accumulation by four species of aquatic plants.

    PubMed

    Skinner, Kathleen; Wright, Nicole; Porter-Goff, Emily

    2007-01-01

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. PMID:16781033

  17. Nanostructure on taro leaves resists fouling by colloids and bacteria under submerged conditions.

    PubMed

    Ma, Jianwei; Sun, Yuekai; Gleichauf, Karla; Lou, Jun; Li, Qilin

    2011-08-16

    The antifouling and self-cleaning properties of plants such as Nelumbo nucifera (lotus) and Colocasia esculenta (taro) have been attributed to the superhydrophobicity resulting from the hierarchical surface structure of the leaf and the air trapped between the nanosized epicuticular wax crystals. The reported study showed that the nanostructures on the taro leaf surfaces were also highly resistant to particle and bacterial adhesion under completely wetted conditions. Adhesion force measurements using atomic force microscopy revealed that the adhesion force on top of the papilla as well as the area around it was markedly lower than that on the edge of an epidermal cell. The decreased adhesion force and the resistance to particle and bacterial adhesion were attributed to the dense nanostructures found on the epidermal papilla and the area surrounding it. These results suggest that engineered surfaces with properly designed nanoscale topographic structures could potentially reduce or prevent particle/bacterial fouling under submerged conditions. PMID:21736298

  18. Increase in liver pigmentation during natural hibernation in some amphibians

    PubMed Central

    BARNI, SERGIO; BERTONE, VITTORIO; CROCE, ANNA CLETA; BOTTIROLI, GIOVANNI; BERNINI, FRANCO; GERZELI, GIUSEPPE

    1999-01-01

    The amount/distribution of liver melanin in 3 amphibian species (Rana esculenta, Triturus a. apuanus, Triturus carnifex) was studied during 2 periods of the annual cycle (summer activity–winter hibernation) by light and electron microscopy, image analysis and microspectrofluorometry. The increase in liver pigmentation (melanin content) during winter appeared to be correlated with morphological and functional modifications in the hepatocytes, which at this period were characterised by a decrease in metabolic activity. These findings were interpreted according to the functional role (e.g. phagocytosis, cytotoxic substance inactivation) played by the pigment cell component in the general physiology of the heterothermic vertebrate liver and, in particular, in relation to a compensatory engagement of these cells against hepatocellular hypoactivity during the winter period. PMID:10473289

  19. [Mushroom poisoning--classification, symptoms and therapy].

    PubMed

    Kohn, R; Mot'ovská, Z

    1997-04-01

    The most serious poisonings are the hepatotoxic ones which are caused above all by Amanita phalloides, virosa, verna, Lepiota helveola, Galerina marginata, Gyromitra esculenta, Hypholoma fasciculare, and nephroptoxic intoxications which are caused above all by Cortinarius orrelanus and Paxillus involutus. Neurotoxic and psychotropic intoxications develop after ingestion of Inocybe, Clitocybe, Amanita-panterina, muscaria and Psilocybe. Most frequently the gastroenteric type of mushroom poisoning is encountered which is caused by many species e.g. Boletus satanas, Entoloma sinuatum and others. In the diagnosis anamnestic data are used, the clinical picture, mycological and toxicological examinations of residues of mushrooms, their spores and toxins. Therapeutic strategy comprises elimination methods gastric lavage, intestinal lavage and administration of large amounts of animal charcoal, forced diuresis, haemoperfusion, haemodialysis or peritoneal dialysis, administration of antidotes and symptomatic treatment, i.e. mainly rehydration and restoration of the mineral balance. Early and comprehensive treatment are important. PMID:9601842

  20. Hypolipidaemic effect of chemically different mucilages in rats: a comparative study.

    PubMed

    Boban, Puthenpura T; Nambisan, Bala; Sudhakaran, Perumana R

    2006-12-01

    Different classes of fibres differ in their potential to lower lipid levels. In order to examine how chemically diverse fibres differ in their hypolipidaemic activity, mucilages of varying chemical composition isolated from three different sources were administered to experimental animals and the metabolism of lipids and lipoproteins was studied. The mucilages used were a galactomannan isolated from fenugreek (Trigonella foenum-graecum) seeds, a glucomannan from Dioscorea esculenta tubers and an arabinogalactan from Colocasia esculenta tubers. Rats were fed these mucilages at a dose of 4 mg/100 g body weight per d for 8 weeks and the changes in the levels of total cholesterol and triacylglycerols in serum, liver and aorta were analysed. All these mucilages decreased lipid levels both in serum and tissues. Among these mucilages, glucomannan showed the most hypolipidaemic effect followed by galactomannan and arabinogalactan. Further, hepatocytes were isolated from the livers of mucilage-fed rats and the synthesis and secretion of lipoproteins were studied using metabolic labelling. There was a decrease in the synthesis and secretion of apoB-containing lipoproteins, mainly VLDL, by hepatocytes isolated from mucilage-fed rats when compared to control (P<0.05). This was further confirmed by pulse chase analysis. Among the different mucilages, mannose-rich glucomannan showed the most effect followed by galactomannan, and mannose-free arabinogalactan showed minimal effect. Comparison of relative viscosity and water-holding capacity showed that mannan-rich mucilages like galactomannan and glucomannan, which showed greater hypolipidaemic effect, had greater relative viscosity and water-holding capacity. The present results suggested that the hypolipidaemic effect of dietary fibre involves a decrease in hepatic production of VLDL and further that it varies with the nature of the fibre. PMID:17181876

  1. Mitospore stages of Disciotis, Gyromitra and Morchella in the inland Pacific Northwest USA.

    PubMed

    Carris, Lori M; Peever, Tobin L; McCotter, Sean W

    2015-01-01

    Colonies of Costantinella species growing on soil, moss and woody debris in the autumn in the inland Pacific Northwest USA were established in culture. Five different mitospore taxa were distinguished based on colony color, presence or absence of setae and internal transcribed spacer region (ITS) rDNA amplicon size. Sequence data from the largest and second largest subunits of RNA polymerase II, translation elongation factor 1-α, D1 and D2 domains of nuclear large subunit rDNA and ITS were used to connect each of the distinct mitospore taxa to corresponding vernal-fruiting Pezizales, including Disciotis cf. venosa, Gyromitra cf. esculenta and three species of Morchella. Both meiospore and mitospore stages of Morchella brunnea and M. populiphila collected in spring and autumn within a meter of each other at two urban sites had identical multilocus haplotypes, providing evidence connecting the two stages of the life cycle. Among other Morchella mitospore stages collected, some had identical haplotypes to previously sampled meiospore stages, while others were distinct, possibly representing undescribed species. Mitospore isolates with sequences assigning them to Disciotis or Gyromitra had different haplotypes from meiospore stages occurring in the same area. Meiospore stages of Disciotis and Gyromitra sampled as part of the study were also genetically distinct from European collections of D. venosa and G. esculenta, indicating more diversity is present in these taxa than is reflected in the current taxonomy. The widespread occurrence of mitospore stages of these fungi suggests that the life cycles of morels, false morels and allied taxa are more complex than previously recognized. PMID:25911699

  2. Petroleum system of the Cano Limon field, Llanos Basin, Colombia

    SciTech Connect

    Molina, J.

    1996-08-01

    The Chipaque-Lower Carbonera({circ}) Petroleum System of the northernmost Llanos Basin of Colombia, covers 11,100 km{sup 2} and includes two major oil fields: Caho Limon in Colombia, and Guafita in Venezuela, jointly with three more relatively small fields in Colombia: Redondo, Cano Rondon, and Jiba. Ultimate recoverable reserves are in the order of 1.4 BBO. The sedimentary section penetrated in the Northern Llanos has been informally subdivided into four Cretaceous formations: K3, K2B, K2A, and Lower K1 deposited during the Albian-Senonian, and into four Tertiary formations: Lower Carbonera, Upper Carbonera, Leon, and Guayabo deposited during the Late Eocene to Pliocene time. The main reservoir is the Lower Carbonera Formation, which contains 81% of the total reserves. The Cretaceous K2A and Lower K1 reservoirs contain 6% and 8%, respectively of the reserves. Minor reserves are accumulated in the discontinuous sandstones of the Oligocene Upper Carbonera Formation Geochemical analyses of the Cano Limon/Guafita oils indicate that these are aromatic intermediate to paraffinic-naphthenic, non degradated, genetically related to a common marine-derived type of kerogen. These oils were generated by a mature, marine clastic source rock with a small contribution of continental organic matter. The geochemistry of the hydrocarbon suggest a genetic relationship with the shales of the Chipaque formation, basin-ward equivalent of the K2 Formation, which presents kerogen type II organic matter and has been recognized as a good source rock. The petroleum system is hypothetical because a definite oil-source rock correlation is lacking. The development of the petroleum system is directly related to the history of movement of the Santa Maria, La Yuca, Caho Limon, and Matanegra wrench faults. It has been determined that these faults of pre-Cretaceous rifting origin, created the Santa Maria Graben of which the Espino Graben is the continuation in Venezuela.

  3. Successful drilling of the first horizontal well in a mature field

    SciTech Connect

    Marruffo, I.; Achong, C.

    1996-08-01

    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.

  4. Floral thermogenesis of three species of Hydnora (Hydnoraceae) in Africa

    PubMed Central

    Seymour, Roger S.; Maass, Erika; Bolin, Jay F.

    2009-01-01

    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. PMID:19584128

  5. In situ Management and Domestication of Plants in Mesoamerica

    PubMed Central

    Casas, Alejandro; Otero-Arnaiz, Adriana; Pérez-Negrón, Edgar; Valiente-Banuet, Alfonso

    2007-01-01

    Background and Aims Ethnobotanical studies in Mexico have documented that Mesoamerican peoples practise systems of in situ management of wild and weedy vegetation directed to control availability of useful plants. In situ management includes let standing, encouraging growing and protection of individual plants of useful species during clearance of vegetation, which in some cases may involve artificial selection. The aim of this study was to review, complement and re-analyse information from three case studies which examined patterns of morphological, physiological and genetic effects of artificial selection in plant populations under in situ management in the region. Methods Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria pumila, the tree Leucaena esculenta subsp. esculenta and the columnar cacti Escontria chiotilla, Polaskia chichipe and Stenocereus stellatus from Central Mexico was re-analysed. Analyses compared morphology and frequency of morphological variants, germination patterns, and population genetics parameters between wild and managed in situ populations of the species studied. Species of columnar cacti are under different management intensities and their populations, including cultivated stands of P. chichipe and S. stellatus, were also compared between species. Key Results Significant differences in morphology, germination patterns and genetic variation documented between wild, in situ managed and cultivated populations of the species studied are associated with higher frequencies of phenotypes favoured by humans in managed populations. Genetic diversity in managed populations of E. chiotilla and P. chichipe is slightly lower than in wild populations but in managed populations of S. stellatus variation was higher than in the wild. However, genetic distance between populations was generally small and influenced more by geographic distance than by management. Conclusions Artificial selection operating on in situ managed populations of the species analysed is causing incipient domestication. This process could be acting on any of the 600–700 plant species documented to be under in situ management in Mesoamerica. In situ domestication of plants could be relevant to understand early processes of domestication and current conditions of in situ conservation of plant genetic resources. PMID:17652338

  6. [Role of the digestive microflora and of the crystalline structure of starch in digestion and dietary efficiency in the chicken. Study of tropical tubers].

    PubMed

    Bewa, H; Charlet-Lery, G; Szylit, O

    1979-01-01

    The influence of microflora in the utilization of starches, the X ray pattern which was of A or B type, was studied by balances and carcasses analysis with growing axenic or holoxenic chickens, put in isolators. Five tropical tubers were used : Manihot utilissima and Dioscorea dumetorum of A-type, Dioscorea cayenensis and alata and Canna edulis of B-type. They were introduced in isoenergetic (4,460 Kcal/g D.M.) and isoproteic (18 p. 100) diets. The A-type starches are entirely digested (95 p. 100) and the B-type are poorly digested (40-60 p. 100). The first ones induced a better growth than the second. The influence of digestive microflora changes with the two types of tubers used. With A-type starches the microflora lowered the feed intake, the growth and the energy and protein efficiency respectively--25 and--10 p. 100. When the diet included tubers with B-type starches, the low digestibility of starch and the low metabolisable energy in the diets induced poor growth and retentions. The results are discussed in relation with the starch breakdown into glucose, lactic acid and volatile fatty acids. PMID:496174

  7. Cassava; African perspective on space agriculture

    NASA Astrophysics Data System (ADS)

    Katayama, Naomi; Njemanze, Philip; Nweke, Felix; Space Agriculture Task Force, J.; Katayama, Naomi; Yamashita, Masamichi

    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.

  8. The Cassava Mealybug (Phenacoccus manihoti) in Asia: First Records, Potential Distribution, and an Identification Key

    PubMed Central

    Parsa, Soroush; Kondo, Takumasa; Winotai, Amporn

    2012-01-01

    Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae), one of the most serious pests of cassava worldwide, has recently reached Asia, raising significant concern over its potential spread throughout the region. To support management decisions, this article reports recent distribution records, and estimates the climatic suitability for its regional spread using a CLIMEX distribution model. The article also presents a taxonomic key that separates P. manihoti from all other mealybug species associated with the genus Manihot. Model predictions suggest P. manihoti imposes an important, yet differential, threat to cassava production in Asia. Predicted risk is most acute in the southern end of Karnataka in India, the eastern end of the Ninh Thuan province in Vietnam, and in most of West Timor in Indonesia. The model also suggests P. manihoti is likely to be limited by cold stress across Vietnam's northern regions and in the entire Guangxi province in China, and by high rainfall across the wet tropics in Indonesia and the Philippines. Predictions should be particularly important to guide management decisions for high risk areas where P. manihoti is absent (e.g., India), or where it has established but populations remain small and localized (e.g., South Vietnam). Results from this article should help decision-makers assess site-specific risk of invasion, and develop proportional prevention and surveillance programs for early detection and rapid response. PMID:23077659

  9. Antithyroid effects in vivo and in vitro of babassu and mandioca: a staple food in goiter areas of Brazil.

    PubMed

    Gaitan, E; Cooksey, R C; Legan, J; Lindsay, R H; Ingbar, S H; Medeiros-Neto, G

    1994-08-01

    Babassu (Orbignya phalerata), a palm-tree coconut fruit, mixed with mandioca (Manihot utilissima) is the staple food of people living in the endemic goiter area of Maranhao in Brazil, where goiter prevalence among schoolchildren was still 38% in 1986 despite an adequate iodine intake in most of the population. Therefore, the question arose as to whether or not the ingestion of babassu alone or mixed with mandioca contributed to the persistence of endemic goiter in this area of Brazil. In this investigation we examined the potential antithyroid effects of babassu and mandioca by means of in vivo studies in Sprague-Dawley rats, in vitro studies in porcine thyroid slices and using a purified porcine thyroid peroxidase (TPO) system. Samples of various edible parts of babassu and mandioca flour were homogenized and extracted in goitrogen-free water (GFW) for in vivo experiments, and in methanol (100 g/l), GFW or 0.06 mol/l phosphate buffer (pH 7.0) for in vitro experiments. The edible parts of babassu produced significant in vivo antithyroid effects (p < 0.05- < 0.001) in rats on a high iodine intake (14 micrograms I- day-1.rat-1), as well as distinct and reproducible antithyroid and anti-TPO activities in both in vitro systems, their action being similar to that of the thionamide-like antithyroid drugs propylthiouracil and methimazole.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8075782

  10. Microbial population, chemical composition and silage fermentation of cassava residues.

    PubMed

    Napasirth, Viengsakoun; Napasirth, Pattaya; Sulinthone, Tue; Phommachanh, Kham; Cai, Yimin

    2015-09-01

    In order to effectively use the cassava (Manihot esculenta Crantz) residues, including cassava leaves, peel and pulp for livestock diets, the chemical and microbiological composition, silage preparation and the effects of lactic acid bacteria (LAB) inoculants on silage fermentation of cassava residues were studied. These residues contained 10(4) to 10(5) LAB and yeasts, 10(3) to 10(4) coliform bacteria and 10(4) aerobic bacteria in colony forming units (cfu) on a fresh matter (FM) basis. The molds were consistently at or below the detectable level (10(2) cfu of FM) in three kinds of cassava residues. Dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) content of cassava residues were 17.50-30.95%, 1.30-16.41% and 25.40-52.90% on a DM basis, respectively. The silage treatments were designed as control silage without additive (CO) or with LAB inoculants Chikuso-1 (CH, Lactobacillus plantarum) and Snow Lacto (SN, Lactobacillus rhamnosus) at a rate of 5 mg/kg of FM basis. All silages were well preserved with a low pH (below 4.0) value and when cassava residues silage treated with inoculants CH and SN improved fermentation quality with a lower pH, butyric acid and higher lactic acid than control silage. PMID:25781881

  11. Bioremediation and Detoxification of Synthetic Wastewater Containing Triarylmethane Dyes by Aeromonas hydrophila Isolated from Industrial Effluent

    PubMed Central

    Ogugbue, Chimezie Jason; Sawidis, Thomas

    2011-01-01

    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

  12. Localization, concentration, and transmission efficiency of Banana bunchy top virus in four asexual lineages of Pentalonia aphids.

    PubMed

    Watanabe, Shizu; Greenwell, April M; Bressan, Alberto

    2013-02-01

    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

  13. Why Amphibians Are More Sensitive than Mammals to Xenobiotics

    PubMed Central

    Quaranta, Angelo; Bellantuono, Vito; Cassano, Giuseppe; Lippe, Claudio

    2009-01-01

    Dramatic declines in amphibian populations have been described all over the world since the 1980s. The evidence that the sensitivity to environmental threats is greater in amphibians than in mammals has been generally linked to the observation that amphibians are characterized by a rather permeable skin. Nevertheless, a numerical comparison of data of percutaneous (through the skin) passage between amphibians and mammals is lacking. Therefore, in this investigation we have measured the percutaneous passage of two test molecules (mannitol and antipyrine) and three heavily used herbicides (atrazine, paraquat and glyphosate) in the skin of the frog Rana esculenta (amphibians) and of the pig ear (mammals), by using the same experimental protocol and a simple apparatus which minimizes the edge effect, occurring when the tissue is clamped in the usually used experimental device. The percutaneous passage (P) of each substance is much greater in frog than in pig. LogP is linearly related to logKow (logarithm of the octanol-water partition coefficient). The measured P value of atrazine was about 134 times larger than that of glyphosate in frog skin, but only 12 times in pig ear skin. The FoD value (Pfrog/Ppig) was 302 for atrazine, 120 for antipyrine, 66 for mannitol, 29 for paraquat, and 26 for glyphosate. The differences in structure and composition of the skin between amphibians and mammals are discussed. PMID:19888346

  14. 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

    SciTech Connect

    Lange, R.H.; Richter, H.P.; Riehl, R.; Zierold, K.; Trandaburu, T.; Magdowski, G.

    1983-05-01

    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. 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.

  15. Accumulation of Heavy Metals and Metalloid in Foodstuffs from Agricultural Soils around Tarkwa Area in Ghana, and Associated Human Health Risks

    PubMed Central

    Bortey-Sam, Nesta; Nakayama, Shouta M. M.; Akoto, Osei; Ikenaka, Yoshinori; Fobil, Julius N.; Baidoo, Elvis; Mizukawa, Hazuki; Ishizuka, Mayumi

    2015-01-01

    This study was carried out to assess the extent of heavy metals and metalloid accumulation from agricultural soils to foodstuffs (viz, M. esculenta (cassava) and Musa paradisiaca (plantain)) around thirteen neighboring communities within Tarkwa, Ghana; and to estimate the human health risk associated with consumption of these foodstuffs. Concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, and Zn were measured with an inductively coupled plasma–mass spectrometer and mercury analysis was done using a mercury analyzer. From the results, 30% of cassava samples collected, contained higher concentrations of Pb when compared to Codex Alimentarius Commission standard values. Bioconcentration factor indicated that Ni had higher capacity of absorption into food crops from soil than the other heavy metals. For both children and adults, the target hazard quotient (THQ) of Pb in cassava in communities such as Techiman, Wangarakrom, Samahu, and Tebe (only children) were greater than 1, which is defined as an acceptable risk value. This indicated that residents could be exposed to significant health risks associated with cassava consumption. PMID:26225988

  16. Development of extruded Ready-To-Eat (RTE) snacks using corn, black gram, roots and tuber flour blends.

    PubMed

    Reddy, M Kavya; Kuna, Aparna; Devi, N Lakshmi; Krishnaiah, N; Kaur, Charanjit; Nagamalleswari, Y

    2014-09-01

    Extruded RTE snacks were prepared from flour blends made with corn flour, Bengal gram flour, roots and tuber flours in a proportion of 60-80: 20: 20 respectively and moisture was adjusted to 17-20 %. The roots and tubers flours were developed from potato (Solanum tuberosum), yam (Dioscorea spp.), sweet potato (Ipomoea batatas L.), taro (Colocassia esculenta) and beet root (Beta vulgaris). Different formulations were extruded at 80 ± 5 °C (heater I) and 95-105 °C (heater II) temperature, 300-350 rpm screw speed, 100 ± 10 °C die temperature and 15 ± 2 kg/h feed rate. The exit diameter of the circular die was 3 mm. Sensory acceptability, physical parameters and nutrient analysis along with storage stability of the products was conducted. The fiber and energy content of the RTE extruded snack improved in experimental samples prepared using root and tuber flours. A serving of 100 g of the snack can provide more than 400 Kcal and 10 g of protein. The overall acceptability of RTE extruded products made with potato and taro were highly acceptable compared to yam and sweet potato. The study demonstrates utilization of roots and tuber flours as potential and diverse ingredients to enhance the appearance and nutritional properties in RTE extruded snack. PMID:25190848

  17. Zoospores of three Arctic laminariales under different UV radiation and temperature conditions: exceptional spectral absorbance properties and lack of phlorotannin induction.

    PubMed

    Müller, Ruth; Wiencke, Christian; Bischof, Kai; Krock, Bernd

    2009-01-01

    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

  18. Analytical characterization of beet root vacuole membrane

    SciTech Connect

    Marty, F.; Branton, D.

    1980-10-01

    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.

  19. The complete chloroplast genome sequence of medicinal plant Pinellia ternata.

    PubMed

    Han, Limin; Chen, Chen; Wang, Bin; Wang, Zhe-Zhi

    2016-07-01

    Pinellia ternata is an important medicinal plant used in the treatment of cough, to dispel phlegm, to calm vomiting and to terminate early pregnancy, as an anti-ulcer and anti-tumor medicine. In this study, we found that the complete chloroplast genome of Pinellia ternata was 164 013 bp in length, containing a pair of inverted repeats of 25 625 bp separated by a large single-copy region and a small single-copy region of 89 783 bp and 22 980 bp, respectively. The chloroplast genome encodes 132 predicted functional genes, including 87 protein-coding genes, eight ribosomal RNA genes, and 37 transfer RNA genes. The chloroplast DNA is GC-rich (36.7%). The phylogenetic analysis showed a strong sister relationship with Colocasia esculenta, which also strongly supports the position of Pinellia ternata. The complete chloroplast genome sequence of Pinellia ternata reported here has the potential to advance population and phylogenetic studies of this medicinal plant. PMID:26153849

  20. Interaction between autumnal temperature-photoperiod and experimentally induced transient cold shock influences proliferative activity in the brain of an adult terrestrial heterothermic vertebrate, Rana bergeri (Günther, 1986).

    PubMed

    Margotta, Vito

    2015-01-01

    It has been shown previously that in adult Rana esculenta, caught in nature, cold-shocked and brain-injured, encephalic cell proliferation is increased when capture and experiment occurred in spring and depressed when they occurred in autumn. Upon exclusive thermal stress cell proliferation appeared weak in spring and intense in autumn. The present study has investigated cold-shocked, but otherwise uninjured Rana bergeri to assess the impact of autumnal environment on encephalic cell proliferation. Lowering temperature--natural or experimental--seemed to exert a mild stimulation on the proliferative activity only in the forebrain. These results complete those previously obtained in spring and appear in substantial agreement with past reports about antithetical interactions between natural (season climate-photoperiod) and experimental (cold stimulus) environmental factors. However, the present results do not seem sufficient to explain the regenerative events described by past authors. A possible explanation of this discrepancy might be that if the spread between the autumnal environmental conditions and the entity of the cold shock is small the latter would be less effective. Alternatively, cold shock may need to be accompanied by further stimuli, such as surgical trauma (partial resection of brain tissue), to achieve extended stimulation and in the absence of those stimuli it would promote cell proliferation only in the forebrain, which is the region best provided with stand-by putative stem cells. PMID:27086419

  1. Evolution and Phylogenetic Diversity of Yam Species (Dioscorea spp.): Implication for Conservation and Agricultural Practices

    PubMed Central

    Ngo Ngwe, Marie Florence Sandrine; Omokolo, Denis Ndoumou; Joly, Simon

    2015-01-01

    Yams (Dioscorea spp.) consist of approximately 600 species. Presently, these species are threatened by genetic erosion due to many factors such as pest attacks and farming practices. In parallel, complex taxonomic boundaries in this genus makes it more challenging to properly address the genetic diversity of yam and manage its germplasm. As a first step toward evaluating and preserving the genetic diversity yam species, we use a phylogenetic diversity (PD) approach that has the advantage to investigate phylogenetic relationships and test hypotheses of species monophyly while alleviating to the problem of ploidy variation within and among species. The Bayesian phylogenetic analysis of 62 accessions from 7 species from three regions of Cameroon showed that most Dioscorea sections were monophyletic, but species within sections were generally non-monophyletic. The wild species D. praehensilis and cultivated D. cayenensis were the species with the highest PD. At the opposite, D. esculenta has a low PD and future studies should focus on this species to properly address its conservation status. We also show that wild species show a stronger genetic structure than cultivated species, which potentially reflects the management of the yam germplasm by farmers. These findings show that phylogenetic diversity is a promising approach for an initial investigation of genetic diversity in a crop consisting of closely related species. PMID:26691919

  2. Extracellular matrix synthesis in blastula and gastrula stages of normal and hybrid frog embryos. I. Toluidine blue and lanthanum staining.

    PubMed

    Johnson, K E

    1977-06-01

    Four developmental stages of Rana pipiens, R. pipiens female X R. catesbeiana female, and R. pipiens female X R. esculenta male embryos were fixed in standard electron microscopic fixatives with or without 1% lanthanum nitrate (LN) added. Embryos fixed without LN were embedded and sectioned at 0-5 micrometer and stained with toluidine blue. Embryos fixed with LN were embedded and sectioned at 70-80 nm and examined in the electron microscope. Both techiques show a dramatic increase in the amount of stainable material in the extracellular matrix during development. Blastula stage embryos have a small amount of material in the extracellular matrix. Early gastrulae have more stainable material than blastulae and this increased amount appears to be due to an accumulation of material in the marginal zone of the embryo, especially near the dorsal lip of the blastopore. Late gastrulae have large amounts of stainable material in the extracellular spaces in almost all parts of the embryo. Interspecific arrested hybrid embryos do not show the same dramatic accumulation of stainable material in their extracellular matrices. PMID:70430

  3. Possible neural network mediating jaw opening during prey-catching behavior of the frog.

    PubMed

    Kovalecz, Gabriella; Kecskes, Szilvia; Birinyi, András; Matesz, Clara

    2015-10-01

    The prey-catching behavior of the frog is a complex, well-timed sequence of stimulus response chain of movements. After visual analysis of the prey, a size dependent program is selected in the motor pattern generator of the brainstem. Besides this predetermined feeding program, various direct and indirect sensory inputs provide flexible adjustment for the optimal contraction of the executive muscles. The aim of the present study was to investigate whether trigeminal primary afferents establish direct contacts with the jaw opening motoneurons innervated by the facial nerve. The experiments were carried out on Rana esculenta (Pelophylax esculentus), where the trigeminal and facial nerves were labeled simultaneously with different fluorescent dyes. Using a confocal laser scanning microscope, close appositions were detected between trigeminal afferent fibers and somatodendritic components of the facial motoneurons. Quantitative analysis revealed that the majority of close contacts were encountered on the dendrites of facial motoneurons and approximately 10% of them were located on the perikarya. We suggest that the identified contacts between the trigeminal afferents and facial motoneurons presented here may be one of the morphological substrate in the feedback and feedforward modulation of the rapidly changing activity of the jaw opening muscle during the prey-catching behavior. PMID:26444079

  4. Evolution and Phylogenetic Diversity of Yam Species (Dioscorea spp.): Implication for Conservation and Agricultural Practices.

    PubMed

    Ngo Ngwe, Marie Florence Sandrine; Omokolo, Denis Ndoumou; Joly, Simon

    2015-01-01

    Yams (Dioscorea spp.) consist of approximately 600 species. Presently, these species are threatened by genetic erosion due to many factors such as pest attacks and farming practices. In parallel, complex taxonomic boundaries in this genus makes it more challenging to properly address the genetic diversity of yam and manage its germplasm. As a first step toward evaluating and preserving the genetic diversity yam species, we use a phylogenetic diversity (PD) approach that has the advantage to investigate phylogenetic relationships and test hypotheses of species monophyly while alleviating to the problem of ploidy variation within and among species. The Bayesian phylogenetic analysis of 62 accessions from 7 species from three regions of Cameroon showed that most Dioscorea sections were monophyletic, but species within sections were generally non-monophyletic. The wild species D. praehensilis and cultivated D. cayenensis were the species with the highest PD. At the opposite, D. esculenta has a low PD and future studies should focus on this species to properly address its conservation status. We also show that wild species show a stronger genetic structure than cultivated species, which potentially reflects the management of the yam germplasm by farmers. These findings show that phylogenetic diversity is a promising approach for an initial investigation of genetic diversity in a crop consisting of closely related species. PMID:26691919

  5. Agricultural Encroachment: Implications for Carbon Sequestration in Tropical African Wetlands

    NASA Astrophysics Data System (ADS)

    Jones, M. B.; Saunders, M.; Kansiime, F.

    2013-12-01

    Tropical wetlands have been shown to exhibit high rates of net primary productivity and may therefore play an important role in global climate change mitigation through carbon assimilation and sequestration. Many permanently flooded areas of tropical East Africa are dominated by the highly productive C4 emergent macrophyte sedge, Cyperus papyrus L. (papyrus). However, increasing population densities around wetland margins in East Africa are reducing the extent of papyrus coverage due to the planting of subsistence crops such as Cocoyam (Colocasia esculenta). We have assessed the impact of this land use change on the carbon cycle in theis wetland environment. Eddy covariance techniques were used, on a campaign basis, to measure fluxes of carbon dioxide over both papyrus and cocoyam dominated wetlands located on the Ugandan shore of Lake Victoria. The integration of flux data over the annual cycle shows that papyrus wetlands have the potential to act as a sink for significant amounts of carbon, in the region of 10 t C ha-1 yr-1. The cocoyam vegetation was found to assimilate ~7 t C ha-1 yr-1 but when carbon exports from crop biomass removal were taken into account these wetlands represent a significant net loss of carbon of similar magnitude. The development of sustainable wetland management strategies are therefore required in order to promote the dual wetland function of crop production and the mitigation of greenhouse gas emissions especially under future climate change scenarios.

  6. Griffipavixanthone, a dimeric xanthone extracted from edible plants, inhibits tumor metastasis and proliferation via downregulation of the RAF pathway in esophageal cancer

    PubMed Central

    Zhang, Hong; Fu, Wenwei; Zhu, Lunlun; Tan, Hongsheng; Xu, Hongxi

    2016-01-01

    Metastasis causes a large number of deaths among esophageal cancer patients. The activation of RAF family proteins elevates tumor metastasis and proliferation. In screen targeting the RAF protein, we identified that Griffipavixanthone (GPX), a dimeric xanthone isolated from Garcinia esculenta, is a B-RAF and C-RAF inhibitor against esophageal cancer cells. Using wound healing, transwell migration and matrigel invasion assays, we confirmed that GPX significantly inhibited cell migration and invasion. Furthermore, exposure to GPX rendered cell proliferation and induced G2/M cell cycle arrest. Our mechanistic study showed that GPX suppressed cancer metastasis and proliferation through downregulation of RAF-MEK-ERK cascades proteins as well as RAF mRNA levels. In a pulmonary metastasis model, the intraperitoneal injection of GPX significantly suppressed esophageal tumor metastasis and ERK protein level in vivo. In conclusion, our present study suggested that GPX could inhibit tumor migration, invasion and proliferation in vitro and in vivo, which indicated the potential of GPX for preventing and treating esophageal cancer. PMID:26646323

  7. Griffipavixanthone, a dimeric xanthone extracted from edible plants, inhibits tumor metastasis and proliferation via downregulation of the RAF pathway in esophageal cancer.

    PubMed

    Ding, Zhijie; Lao, Yuanzhi; Zhang, Hong; Fu, Wenwei; Zhu, Lunlun; Tan, Hongsheng; Xu, Hongxi

    2016-01-12

    Metastasis causes a large number of deaths among esophageal cancer patients. The activation of RAF family proteins elevates tumor metastasis and proliferation. In screen targeting the RAF protein, we identified that Griffipavixanthone (GPX), a dimeric xanthone isolated from Garcinia esculenta, is a B-RAF and C-RAF inhibitor against esophageal cancer cells. Using wound healing, transwell migration and matrigel invasion assays, we confirmed that GPX significantly inhibited cell migration and invasion. Furthermore, exposure to GPX rendered cell proliferation and induced G2/M cell cycle arrest. Our mechanistic study showed that GPX suppressed cancer metastasis and proliferation through downregulation of RAF-MEK-ERK cascades proteins as well as RAF mRNA levels. In a pulmonary metastasis model, the intraperitoneal injection of GPX significantly suppressed esophageal tumor metastasis and ERK protein level in vivo. In conclusion, our present study suggested that GPX could inhibit tumor migration, invasion and proliferation in vitro and in vivo, which indicated the potential of GPX for preventing and treating esophageal cancer. PMID:26646323

  8. A host plant genome (Zizania latifolia) after a century-long endophyte infection.

    PubMed

    Guo, Longbiao; Qiu, Jie; Han, Zujing; Ye, Zihong; Chen, Chao; Liu, Chuanjun; Xin, Xiufang; Ye, Chu-Yu; Wang, Ying-Ying; Xie, Hongqing; Wang, Yu; Bao, Jiandong; Tang, She; Xu, Jie; Gui, Yijie; Fu, Fei; Wang, Weidi; Zhang, Xingchen; Zhu, Qianhua; Guang, Xuanmin; Wang, Chongzhi; Cui, Haifeng; Cai, Daguang; Ge, Song; Tuskan, Gerald A; Yang, Xiaohan; Qian, Qian; He, Sheng Yang; Wang, Jun; Zhou, Xue-Ping; Fan, Longjiang

    2015-08-01

    Despite the importance of host-microbe interactions in natural ecosystems, agriculture and medicine, the impact of long-term (especially decades or longer) microbial colonization on the dynamics of host genomes is not well understood. The vegetable crop 'Jiaobai' with enlarged edible stems was domesticated from wild Zizania latifolia (Oryzeae) approximately 2000 years ago as a result of persistent infection by a fungal endophyte, Ustilago esculenta. Asexual propagation via infected rhizomes is the only means of Jiaobai production, and the Z. latifolia-endophyte complex has been maintained continuously for two centuries. Here, genomic analysis revealed that cultivated Z. latifolia has a significantly smaller repertoire of immune receptors compared with wild Z. latifolia. There are widespread gene losses/mutations and expression changes in the plant-pathogen interaction pathway in Jiaobai. These results show that continuous long-standing endophyte association can have a major effect on the evolution of the structural and transcriptomic components of the host genome. PMID:26072920

  9. Localization, Concentration, and Transmission Efficiency of Banana bunchy top virus in Four Asexual Lineages of Pentalonia aphids

    PubMed Central

    Watanabe, Shizu; Greenwell, April M.; Bressan, Alberto

    2013-01-01

    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

  10. Propulsive force calculations in swimming frogs. II. Application of a vortex ring model to DPIV data.

    PubMed

    Stamhuis, Eize J; Nauwelaerts, Sandra

    2005-04-01

    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

  11. Differential expression of KCNQ1 K+ channel in tubular cells of frog kidney

    PubMed Central

    Ćirović, S.; Marković-Lipkovski, J.; Todorović, J.; Nešović-Ostojić, J.; Jović, M.; Ilić, S.; Tatić, S.; Ćemerikić, D.

    2010-01-01

    The aim of this study was to evaluate KCNQ1 K+ channel expression in the frog kidney of Rana esculenta. KCNQ1 K+ channel, also known as KvLQT1, is the pore forming α-subunit of the IKs K+ channel, a delayed rectifier voltage-gated K+ channel, which has an important role in water and salt transport in the kidney and gastrointestinal tract. The expression of KCNQ1 K+ channel along tubular epithelium differs from species to species. In the present study the expression of KCNQ1 K+ channel in the frog kidney has been demonstrated by immunohistochemistry. The presence of KCNQ1 K+ channel was demonstrated in the epithelial cells of distal convoluted tubule and collecting duct. However, the pattern of expression of KCNQ1 K+ channel differs between distal convoluted tubules and collecting duct. All epithelial cells of distal convoluted tubules revealed basolateral expression of KCNQ1 K+ channel. On the contrary, only the single cells of collecting duct, probably intercalated cells, showed diffuse cell surface staining with antibodies against KCNQ1 K+ channel. These findings suggest that KCNQ1 K+ channel has cell-specific roles in renal potassium ion transport. PMID:20353914

  12. Uses of mushrooms by Finns and Karelians.

    PubMed

    Härkönen, M

    1998-01-01

    Finns have adopted two traditions of mushroom use: one, the old Roman tradition, came through France and Sweden to the educated, mostly Swedish speaking people of southwest Finland; the other came from the east via Karelia and was adopted by ordinary country folk. This eastern tradition is still maintained among the Karelinas living in Tver government in Russia. Even the use of Amanita muscaria for killing flies is still utilized there. The western tradition favoured chanterelles and Boletus edulis, the eastern acrid milk caps, the Lactarius species. During the famines in the 1860's and after the World War II the government authorities tried to promote the use of wild mushrooms, but the real impulse to a more versatile mushroom use was initiated after the war when 400,000 evacuees from that part of Karelia conquered by the Soviet Union were resettled among farming families all over Finland. In 1969 the National Board of Forestry began to train mushroom advisors, a programme which still continues. In 1981 Finland passed a statute on edible mushrooms and drew up a list of commercial species. Even today the largest percentage of marketed mushrooms comes from Eastern Finland and the Lactarius tivialis species sells best. Gyromitra esculenta, the false morel is considered a delicacy. Today picking mushrooms is a passionate hobby for many Finns. PMID:9567575

  13. Comparative study of contents of several bioactive components in fruiting bodies and mycelia of culinary-medicinal mushrooms.

    PubMed

    Lo, Yu-Chang; Lin, Shin-Yi; Ulziijargal, Enkhjargal; Chen, Shin-Yu; Chien, Rao-Chi; Tzou, Yi-Jing; Mau, Jeng-Leun

    2012-01-01

    Mushrooms have been consumed for thousands of years, and several bioactive components were found therein, including lovastatin, γ-aminobutyric acid (GABA) and ergothioneine. The study reported herein was to analyze these three bioactive components in 15 fruiting bodies and 9 mycelia of 19 species of mushrooms from genera Agaricus, Agrocybe, Auricularia, Boletus, Ganoderma, Hypsizygus, Inonotus, Lentinus, Morchella, Pleurotus, Tremella, Termitomyces, and Volvariella. The results show that Hypsizygus marmoreus contained the highest amount of lovastatin (628.05 mg/kg) in fruiting bodies and Morchella esculenta contained the highest amount (1438.42 mg/ kg) in mycelia. Agaricus brasiliensis contained the highest amount of GABA (1844.85 mg/kg) in fruiting bodies, and mycelia of Boletus edulis, Pleurotus citrinopileatus, and Termitomyces albuminosus contained extraordinarily higher amounts (1274.03, 1631.67, and 2560.00 mg/kg, respectively). Volvariella volvacea contained the highest amount of ergothioneine (537.27 mg/kg) in fruiting bodies and mycelia; Boletus edulis, Pleurotus ferulae, and P. salmoneostramineus contained relatively higher amount of ergothioneine too (258.03, 250.23, and 222.08 mg/kg, respectively). However, none of these components was detected in fruiting bodies of Inonotus obliquus. In conclusion, these three bioactive components were commonly found in most mushrooms, and these results might be related to their beneficial effects. PMID:23510173

  14. Pyrethroid stimulation of ion transport across frog skin.

    PubMed

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

    2003-06-01

    Pyrethroids are grouped into two classes (types I and II) because of the absence or presence of an alpha-cyano substituent and the production of a different intoxication syndrome in rodents. In this study, we investigated the effect of pyrethroids on the ion transport across frog skin (Rana esculenta). The short-circuit current value (estimate of ion transport) was increased by each of the eight pyrethroids tested, with the following order of potency: lambda-cyhalothrin > deltamethrin > alpha-cypermethrin = beta-cyfluthrin > bioallethrin > permethrin > bioresmethrin > phenothrin. The first four compounds are type II pyrethroids. Therefore, ion transport is stimulated more by type II pyrethroids than by type I. Experiments performed in the presence of amiloride support the conclusion that pyrethroids mainly increase Na+ absorption and to a lesser extent Cl- secretion. In these experiments, no systematic difference between type I and II pyrethroids was found. Finally, the stimulation by pyrethroids was inhibited by indomethacin and W7 (inhibitors of cyclooxygenases and the Ca2+/calmodulin system, respectively). These observations suggest that pyrethroids do not directly affect the epithelial Na+ channel (ENaC) but indirectly influence an intracellular event involved in ENaC modulation and linked to the Ca2+ signaling cascade. PMID:12785591

  15. Late Quaternary environments, vegetation and agriculture in northern New Zealand

    NASA Astrophysics Data System (ADS)

    Horrocks, M.; Nichol, S. L.; Augustinus, P. C.; Barber, I. G.

    2007-03-01

    A sedimentological and plant microfossil history of the Late Quaternary is preserved in two sediment cores from early Polynesian ditch systems on southern Aupouri Peninsula. The study places human activities into a geomorphological and ecological context and allows comparison of natural and anthropogenic effects on two different geological settings: a floodplain and a relatively closed peat swamp. The data fill part of the current gap in the environmental record from northern New Zealand, namely MIS 3 (57k-26k yr BP). There is evidence for an increase in fire frequency in the region after 40k 14C yr BP, suggesting a shift to drier (and cooler) conditions. Pollen records show that conifer-hardwood forest dominated by podocarps (especially Dacrydium) prevailed prior to Polynesian arrival and deforestation within the last millennium, with Fuscopsora insignificant throughout. Both cores show sections with gaps in deposition or preservation, possible flood-stripping of peat during the pre-Holocene and mechanical disturbance by early Polynesians. The identification of prehistoric starch grains and other microremains of introduced Colocasia esculenta (taro) in both cores supports indirect evidence that the ditch systems of far northern New Zealand were used for the extensive cultivation of this crop. Copyright

  16. Cost-Benefit Analysis of Managing the Papuana uninodis (Coleoptera: Scarabaeidae) Taro Beetle in Fiji.

    PubMed

    Brown, P; Daigneault, A

    2014-10-01

    Taro (Colocasia esculenta (L.) Schott) plays a prominent role in the economies and cultures of Pacific Island countries such as Fiji. Unfortunately, taro is highly susceptible to invasion from taro beetles, which burrow into the corms and weaken the plants, rendering them unmarkable and prone to rot. Papuana uninodis Prell, an invasive alien species that is native to the Solomon Islands and Vanuatu, was first reported on Viti Levu (Fiji's largest island) in 1984. Since that time, taro production on Viti Levu has fallen substantially. In this paper, we employ data from surveys of households and communities to document the impacts of P. uninodis on Viti Levu. We then identify three management approaches-chemical controls, cultural controls, and switching from taro to another staple crop-and conduct a cost-benefit analysis of each. We find strong arguments for pursuing chemical control, which derives a net present value of monetised benefits of about FJ$139,500 per hectare over 50 yr, or >FJ$21 for each FJ$1 spent. Still, any of the three management options is more efficient than no management, even without any attempt to quantify the benefits to biodiversity or forest protection, underscoring the value of actively managing this invasive alien species. PMID:26309277

  17. Green Technology for the Removal of Chloro-Organics from Pulp and Paper Mill Wastewater.

    PubMed

    Choudhary, Ashutosh Kumar; Kumar, Satish; Sharma, Chhaya; Kumar, Vivek

    2015-07-01

    This study evaluates the treatment efficiency of a horizontal subsurface-flow constructed wetland (HSSF-CW) for the removal of chloro-organic compounds from pulp and paper mill wastewater. The surface area of the HSSF-CW unit was 5.25 m² and was planted with Colocasia esculenta. The wastewater was characterized for different chloro-organic compounds, that is, adsorbable organic halides (AOX), chlorophenolics, and chlorinated resin and fatty acids (cRFAs). Under a hydraulic retention time of 5.9 days, the average AOX, chlorophenolics, and cRFA removal from wastewater was 87, 87, and 93%, respectively. Some of the chlorophenolics were found to accumulate in the plant biomass and soil material. The mass balance studies show that a significant fraction of chlorophenolics and cRFA was degraded in the constructed wetland system. Modeling studies were carried out to estimate the first-order area-based removal rate constants (k) for chemical oxygen demand removal. The HSSF-CW was found to be an effective treatment technology for the remediation of pulp and paper mill wastewater. PMID:26163503

  18. Host specificity and growth of kelp gametophytes symbiotic with filamentous red algae (Ceramiales, Rhodophyta)

    NASA Astrophysics Data System (ADS)

    Hubbard, Charlene B.; Garbary, David J.; Kim, Kwang Young; Chiasson, David M.

    2004-02-01

    Kelp gametophytes were previously observed in nature living endophytically in red algal cell walls. Here we examine the interactions of two kelp species and six red algae in culture. Gametophytes of Nereocystis luetkeana (Mertens) Postels et Ruprecht became endophytic in the cell walls of Griffithsia pacifica Kylin and Antithamnion defectum Kylin, and grew epiphytically in high abundance on G. japonica Okamura and Aglaothamnion oosumiense Itono. Alaria esculenta (Linnaeus) Greville from the Atlantic coast of Nova Scotia became endophytic in Aglaothamnion oosumiense, Antithamnion defectum, Callithamnion sp., G. japonica, G. pacifica, and Pleonosporium abysicola Gardner, all from the Pacific Ocean. Some cultures were treated with phloroglucinol before infection to thicken the cell walls. The endophytic gametophytes were smaller and grew more slowly than gametophytes epiphytic on the same host. N. luetkeana failed to become endophytic in some of the potential hosts, and this may reflect host specificity, or culture artifacts. This work improves our understanding of the process of infection of red algae by kelp gametophytes, and broadens our knowledge of host specificity in endophytic symbioses.

  19. The Medicinal Uses of Poi

    PubMed Central

    Brown, Amy C.; Valiere, Ana

    2006-01-01

    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. PMID:15481740

  20. Accumulation of Heavy Metals and Metalloid in Foodstuffs from Agricultural Soils around Tarkwa Area in Ghana, and Associated Human Health Risks.

    PubMed

    Bortey-Sam, Nesta; Nakayama, Shouta M M; Akoto, Osei; Ikenaka, Yoshinori; Fobil, Julius N; Baidoo, Elvis; Mizukawa, Hazuki; Ishizuka, Mayumi

    2015-08-01

    This study was carried out to assess the extent of heavy metals and metalloid accumulation from agricultural soils to foodstuffs (viz, M. esculenta (cassava) and Musa paradisiaca (plantain)) around thirteen neighboring communities within Tarkwa, Ghana; and to estimate the human health risk associated with consumption of these foodstuffs. Concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, and Zn were measured with an inductively coupled plasma-mass spectrometer and mercury analysis was done using a mercury analyzer. From the results, 30% of cassava samples collected, contained higher concentrations of Pb when compared to Codex Alimentarius Commission standard values. Bioconcentration factor indicated that Ni had higher capacity of absorption into food crops from soil than the other heavy metals. For both children and adults, the target hazard quotient (THQ) of Pb in cassava in communities such as Techiman, Wangarakrom, Samahu, and Tebe (only children) were greater than 1, which is defined as an acceptable risk value. This indicated that residents could be exposed to significant health risks associated with cassava consumption. PMID:26225988

  1. Food processing methods influence the glycaemic indices of some commonly eaten West Indian carbohydrate-rich foods.

    PubMed

    Bahado-Singh, P S; Wheatley, A O; Ahmad, M H; Morrison, E Y St A; Asemota, H N

    2006-09-01

    Glycaemic index (GI) values for fourteen commonly eaten carbohydrate-rich foods processed by various methods were determined using ten healthy subjects. The foods studied were round leaf yellow yam (Dioscorea cayenensis), negro and lucea yams (Dioscorea rotundata), white and sweet yams (Dioscorea alata), sweet potato (Solanum tuberosum), Irish potato (Ipomoea batatas), coco yam (Xanthosoma spp.), dasheen (Colocasia esculenta), pumpkin (Cucurbita moschata), breadfruit (Artocarpus altilis), green banana (Musa sapientum), and green and ripe plantain (Musa paradisiaca). The foods were processed by boiling, frying, baking and roasting where applicable. Pure glucose was used as the standard with a GI value of 100. The results revealed marked differences in GI among the different foods studied ranging from 35 (se 3) to 94 (se 8). The area under the glucose response curve and GI value of some of the roasted and baked foods were significantly higher than foods boiled or fried (P<0.05). The results indicate that foods processed by roasting or baking may result in higher GI. Conversely, boiling of foods may contribute to a lower GI diet. PMID:16925852

  2. SNP markers identify widely distributed clonal lineages of Phytophthora colocasiae in Vietnam, Hawaii and Hainan Island, China.

    PubMed

    Shrestha, Sandesh; Hu, Jian; Fryxell, Rebecca Trout; Mudge, Joann; Lamour, Kurt

    2014-01-01

    Taro (Colocasia esculenta) is an important food crop, and taro leaf blight caused by Phytophthora colocasiae can significantly affect production. Our objectives were to develop single nucleotide polymorphism (SNP) markers for P. colocasiae and characterize populations in Hawaii (HI), Vietnam (VN) and Hainan Island, China (HIC). In total, 379 isolates were analyzed for mating type and multilocus SNP profiles including 214 from HI, 97 from VN and 68 from HIC. A total of 1152 single nucleotide variant (SNV) sites were identified via restriction site-associated DNA (RAD) sequencing of two field isolates. Genotyping with 27 SNPs revealed 41 multilocus SNP genotypes grouped into seven clonal lineages containing 2-232 members. Three clonal lineages were shared among countries. In addition, five SNP markers had a low incidence of loss of heterozygosity (LOH) during asexual laboratory growth. For HI and VN, >95% of isolates were the A2 mating type. On HIC, isolates within single clonal lineages had A1, A2 and A0 (neuter) isolates. The implications for the wide dispersal of clonal lineages are discussed. PMID:24895424

  3. Adaptability in stone tool use by wild capuchin monkeys (Sapajus libidinosus).

    PubMed

    De Moraes, Bárbara Lins Caldas; Da Silva Souto, Antonio; Schiel, Nicola

    2014-10-01

    Capuchin monkeys are well known for population variation in the use of stone tools and the types of food items consumed. In order to determine adaptability in stone tool use, we investigated a never before studied population of wild capuchin monkey (Sapajus libidinosus) displaying terrestrial habits in a Caatinga environment. To carry out this study we recorded physical evidence of the use of stone tools as well as made direct observations through trap cameras. During a 15-month period, we studied a group of Sapajus libidinosus in Serra Talhada, Pernambuco, Brazil. In total, 257 anvils and 395 hammers were identified, characterized, and monitored. We identified five types of food items exploited at these "tool use sites": Syagrus oleracea (catolé palm), Manihot epruinosa (manioc), Pilosocereus pachycladus (facheiro), Tacinga inamoena (quípa), and Commiphora leptophloeos (imburana de cambão). Five hundred three video clips of capuchin monkeys were recorded, 43 of which involved the use of stone tools. The results indicated evidence of adaptability in tool use by the capuchins. We verified that the rigidity and size of the food item, along with the presence or absence of spines seem to influence the choice of stone tools made by the animals for processing the food. The recurring use of tools for the processing of cacti was especially noteworthy and it appears that the presence of spines predisposes the capuchins to use stones to process them. A significant difference was observed between the characteristics of the anvils and the weight of the hammers according to the food item consumed. The use of tools enabled the animals to access otherwise unavailable or difficult to acquire food items within a Caatinga habitat. Adaptability in the use of stone tools by the capuchin monkey population of Serra Talhada provides an example of the complexity that these primates demonstrate in food processing. PMID:24753103

  4. Prophylactic effects of quercetin and hyperoside in a calcium oxalate stone forming rat model.

    PubMed

    Zhu, Wei; Xu, Yun-fei; Feng, Yuan; Peng, Bo; Che, Jian-ping; Liu, Min; Zheng, Jun-hua

    2014-12-01

    Quercetin and hyperoside (QH) are the two main constituents of the total flavone glycosides of Flos Abelmoschus manihot, which has been prescribed for treating chronic kidney disease for decades. This study aimed to investigate the effect of QH on calcium oxalate (CaOx) formation in ethylene glycol (EG)-fed rats. Rats were divided into three groups: an untreated stone-forming group, a QH-treated stone-forming group (20 mg/kg/day) and a potassium citrate-treated stone-forming group (potassium citrate was a worldwide-recognized calculi-prophylactic medicine). Ethylene glycol (0.5 %) was administered to the rats during the last week, and vitamin D3 was force-fed to induce hyperoxaluria and kidney calcium oxalate crystal deposition. 24 h urine samples were collected before and after inducing crystal deposits. Rats were killed and both kidneys were harvested after 3 weeks. Bisected kidneys were examined under a polarized light microscope for semi-quantification of the crystal-formation. The renal tissue superoxide dismutase and catalase levels were measured by Western blot. QH and potassium citrate have the ability to alkalinize urine. The number of crystal deposits decreased significantly in the QH-treated stone-forming group as compared to the other groups. Superoxide dismutase and catalase levels also increased significantly in the QH-treated stone-forming group, as compared with the untreated stone-forming group. QH administration has an inhibitory effect on the deposition of CaOx crystal in EG-fed rats and may be effective for preventing stone-forming disease. PMID:25085199

  5. Sarcomere-length dependence of myosin filament structure in skeletal muscle fibres of the frog.

    PubMed

    Reconditi, Massimo; Brunello, Elisabetta; Fusi, Luca; Linari, Marco; Martinez, Manuel Fernandez; Lombardi, Vincenzo; Irving, Malcolm; Piazzesi, Gabriella

    2014-03-01

    X-ray diffraction patterns were recorded at beamline ID02 of the European Synchrotron Radiation Facility from small bundles of skeletal muscle fibres from Rana esculenta at sarcomere lengths between 2.1 and 3.5 μm at 4°C. The intensities of the X-ray reflections from resting fibres associated with the quasi-helical order of the myosin heads and myosin binding protein C (MyBP-C) decreased in the sarcomere length range 2.6-3.0 μm but were constant outside it, suggesting that an OFF conformation of the thick filament is maintained by an interaction between MyBP-C and the thin filaments. During active isometric contraction the intensity of the M3 reflection from the regular repeat of the myosin heads along the filaments decreased in proportion to the overlap between thick and thin filaments, with no change in its interference fine structure. Thus, myosin heads in the regions of the thick filaments that do not overlap with thin filaments are highly disordered during isometric contraction, in contrast to their quasi-helical order at rest. Heads in the overlap region that belong to two-headed myosin molecules that are fully detached from actin are also highly disordered, in contrast to the detached partners of actin-attached heads. These results provide strong support for the concept of a regulatory structural transition in the thick filament involving changes in both the organisation of the myosin heads on its surface and the axial periodicity of the myosin tails in its backbone, mediated by an interaction between MyBP-C and the thin filaments. PMID:24344169

  6. Mechanical properties, anisotropic swelling behaviours and structures of jellyfish mesogloea.

    PubMed

    Zhu, Jintang; Wang, Xuezhen; He, Changcheng; Wang, Huiliang

    2012-02-01

    Learning from nature is a promising way for designing and fabricating new materials with special properties. As the first step, we need to understand the structures and properties of the natural materials. In this work, we paid attention to the mesogloea of an edible jellyfish (Rhopilema esculenta Kishinouye) and mainly focused on its structure, mechanical and swelling properties. Scanning electron microscope (SEM) investigations show that jellyfish mesogloea has a well-developed anisotropic microstructure, which consists of nano-sized membranes connected with many fibres. The tensile and compressive properties of swollen and dried jellyfish mesogloea samples are measured. The jellyfish mesogloea displays very high tensile strength (0.17 MPa) and compressive strength (1.43 MPa) even with 99 wt % water. The mechanical properties of jellyfish mesogloea exceed most synthetic hydrogels with similar or even lower water contents. Swelling in acidic and basic buffer solutions weakens the mechanical properties of jellyfish mesogloea. The dried jellyfish mesogloea has very high tensile strength and modulus, which are very similar to those of synthetic plastics. The swelling properties of jellyfish mesogloea in solutions with different pH values were studied. The jellyfish mesogloea exhibits pH-sensitive and anisotropic swelling properties. The jellyfish mesogloea swells (expands) in height but deswells (shrinks) in length and width, without significant change in the volume. This phenomenon has never been reported for synthetic hydrogels. This study may provide gel scientists new ideas in designing and fabricating hydrogels with well-defined microstructures and unique mechanical and swelling properties. PMID:22301174

  7. Induction of a T-Helper 1 (Th1) immune response in mice by an extract from the Pleurotus eryngii (Eringi) mushroom.

    PubMed

    Ike, Kazunori; Kameyama, Natsuko; Ito, Akira; Imai, Soichi

    2012-12-01

    To assess the effect of edible mushroom extracts on the induction of T-helper 1 (Th1) immunity, we examined differences in interferon-gamma (IFN-γ) and interleukin (IL)-4 production in mice induced by hot-water extracts of 15 species of edible mushroom. Extracts from Agaricus bisporus, Flammulina velutipes, Hypsizigus marmoreus, Lentinula edodes, and Lyophyllum decastes induced both IFN-γ and IL-4 production in mice, whereas extracts from Pleurotus ostreatus only induced IL-4. In contrast, extracts from Agaricus blazei, Grifola frondosa, Morchella esculenta, Pholiota nameko, Pleurotus citrinopileatus, and Pleurotus eryngii induced only IFN-γ production. In particular, the extract from P. eryngii induced high levels of IFN-γ and reduced levels of IL-4. We further investigated the use of a trial immunogen using the P. eryngii extract as a Th1 immunostimulator. An oil-in-water emulsion of the hot-water extract from P. eryngii (immunostimulator) and ovalbumin (OVA; antigen) was used as a trial immunogen. This immunogen induced strong OVA-specific IgG2a antibody production in mice compared with the negative controls. In addition, OVA-specific IgG1 antibody levels were lower than those for the negative controls. Marked increases in serum IFN-γ levels and high-level production of IFN-γ in the culture supernatant from the CD4(+) spleen cells in the trial immunogen group mice were observed. Our results suggested that the hot-water extract from P. eryngii induced Th1 immunity by acting as an immunostimulator. PMID:23134464

  8. Induction of a T-Helper 1 (Th1) Immune Response in Mice by an Extract from the Pleurotus eryngii (Eringi) Mushroom

    PubMed Central

    Kameyama, Natsuko; Ito, Akira; Imai, Soichi

    2012-01-01

    Abstract To assess the effect of edible mushroom extracts on the induction of T-helper 1 (Th1) immunity, we examined differences in interferon-gamma (IFN-γ) and interleukin (IL)-4 production in mice induced by hot-water extracts of 15 species of edible mushroom. Extracts from Agaricus bisporus, Flammulina velutipes, Hypsizigus marmoreus, Lentinula edodes, and Lyophyllum decastes induced both IFN-γ and IL-4 production in mice, whereas extracts from Pleurotus ostreatus only induced IL-4. In contrast, extracts from Agaricus blazei, Grifola frondosa, Morchella esculenta, Pholiota nameko, Pleurotus citrinopileatus, and Pleurotus eryngii induced only IFN-γ production. In particular, the extract from P. eryngii induced high levels of IFN-γ and reduced levels of IL-4. We further investigated the use of a trial immunogen using the P. eryngii extract as a Th1 immunostimulator. An oil-in-water emulsion of the hot-water extract from P. eryngii (immunostimulator) and ovalbumin (OVA; antigen) was used as a trial immunogen. This immunogen induced strong OVA-specific IgG2a antibody production in mice compared with the negative controls. In addition, OVA-specific IgG1 antibody levels were lower than those for the negative controls. Marked increases in serum IFN-γ levels and high-level production of IFN-γ in the culture supernatant from the CD4+ spleen cells in the trial immunogen group mice were observed. Our results suggested that the hot-water extract from P. eryngii induced Th1 immunity by acting as an immunostimulator. PMID:23134464

  9. Functional properties of thermally treated legume flours.

    PubMed

    Nagmani, B; Prakash, J

    1997-05-01

    Functional properties of four thermally treated decorticated legume flours namely, bengal gram (Cicer arietinum), black gram (Phaseolus f1p4o Roxb.), green gram (Phaseolus aureus Roxb.) and lentils (Lens esculenta) were studied. Samples with moisture levels of 3.2, 3.3, 1.3 and 5.0% for all four were subjected to dry heat treatment in a covered vessel in pressure cooker. (Untreated flours served as controls. Thermal treatment lowered nitrogen solubility profiles of all flours and increased water absorption capacities in bengal gram (146) black gram (451) and lentil (206) over control values of 138, 441 and 180 ml/100 g of flour respectively. Fat absorption capacities decreased in thermally treated bengal gram and black gram (242 and 292) as against 298 and 303 ml/100 g for untreated samples respectively. Foaming capacity also showed a decrease in thermally treated bengal gram and black gram by 28 and 53% respectively over controls. Two deep fat fried Indian products namely, 'Seviya' and 'Chakli' were prepared using two of the legumes. Proximate compositional analysis revealed that products prepared with thermally treated flours absorbed less fat. The sensory scores for appearance, texture, flavour and overall quality obtained by Seviya were 6.04, 6.20, 5.98 and 6.40 for products prepared with untreated flour and 5.74, 5.78, 5.70 and 5.68 for product prepared with treated flour respectively. Chakli prepared with thermally treated flour obtained significantly lower scores of 6.08, 5.2, 5.42, and 5.88 as against 6.78, 6.68, 6.68 and 6.88 obtained by products prepared with untreated flour for similar attributes. PMID:9205596

  10. True morels (Morchella, Pezizales) of Europe and North America: evolutionary relationships inferred from multilocus data and a unified taxonomy.

    PubMed

    Richard, Franck; Bellanger, Jean-Michel; Clowez, Philippe; Hansen, Karen; O'Donnell, Kerry; Urban, Alexander; Sauve, Mathieu; Courtecuisse, Régis; Moreau, Pierre-Arthur

    2015-01-01

    Applying early names, with or without original material, to genealogical species is challenging. For morels this task is especially difficult because of high morphological stasis and high plasticity of apothecium color and shape. Here we propose a nomenclatural revision of true morels (Morchella, Pezizales) from Europe and North America, based on molecular phylogenetic analyses of portions of the genes for RNA polymerase II largest subunit (RPB1) and second largest subunit (RPB2), translation elongation factor-1α (TEF1), the nuc rDNA region encompassing the internal transcribed spacers 1 and 2, along with the 5.8S rDNA (ITS), and partial nuc 28S rDNA D1-D2 domains (28S). The 107 newly sequenced collections were from both continents, including 48 types, together with previously published sequences. Names are applied to 30 of the 65 currently recognized genealogical species. Results of the present study revealed that the number of Morchella species in Europe (n = 21) is nearly identical to that in North America (n = 22). Only seven species were found on both continents, consistent with previous reports of high continental endemism within the genus. Presently it is not possible to tell whether the transoceanic disjunctions were due to human activities, migration across a Bering land bridge or long-distance dispersal. In an effort to stabilize the taxonomy, due in part to the recent publication of synonyms for 11 of the species, accepted names are presented together with their corresponding later synonyms. A new subclade that includes holotypes of M. castanea and M. brunneorosea is identified in sect. Morchella (Esculenta Clade). Lectotypes for Morchella deliciosa, M. eximia and M. tridentina are designated here, as well as epitypes for M. dunalii, M. eximia, M. purpurascens and M. vulgaris. Morchella conica was determined to be illegitimate, and further research is required to determine the identity of M. elata and M. inamoena. PMID:25550303

  11. Uptake, translocation and metabolism of decabromodiphenyl ether (BDE-209) in seven aquatic plants.

    PubMed

    Deng, Daiyong; Liu, Jin; Xu, Meiying; Zheng, Guolu; Guo, Jun; Sun, Guoping

    2016-06-01

    Terrestrial plant uptake of PBDEs from contaminated soils has been widely reported recently. In this study the fate of deca-BDE within a plant/PBDEs/aquatic environment system was investigated through simulated pot experiments. Accumulations of the total PBDEs and deca-BDE were observed in tissues of seven test aquatic plant species, namely Phragmites australis, Cyperus papyrus, Alternanthera philoxeroides, Colocasia esculenta, Scirpus validus, Acorus calamus and Oryza sativa. In all seven plants, O. sativa leads the uptake and accumulation both in the total PBDEs (444.8 ng g(-1)) and deca-BDE (368.0 ng g(-1)) in roots. Among the six common phytoremediation aquatic plants, A. calamus leads the uptake (236.2 ng g(-1)), and P. australis leads the translocation (Cshoot/Croot = 0.35), while A. philoxeroides (43.4%) and P. australis (80.0%) lead in the metabolism efficiencies in the root and shoot, respectively. The detection of seventeen lesser brominated PBDE congeners provided the debromination evidence, and the specific PBDEs profiles in test plant species indicated there is no common metabolic pattern. Furthermore, a relative high proportion of lesser brominated PBDE congeners in shoots suggested the possible metabolic difference between roots and shoots. Finally, a noticeable percentage of penta- and octa-BDE derived from deca-BDE also hint the ecological risk in deca-BDE use. This comparative research on the aquatic plants provide a broad vision on the understanding of plant/PBDEs/aquatic environment interaction system, and may be applied to remediate PBDEs in contaminated waters and sediments. PMID:26994429

  12. Biotrophic interaction of Sporisorium scitamineum on a new host-Saccharum spontaneum.

    PubMed

    Jose, Robinson C; Louis, Bengyella; Goyari, Sailendra; Waikhom, Sayanika D; Handique, Pratap J; Talukdar, Narayan C

    2016-02-01

    Sporisorium scitamineum is a biotrophic smut fungus harbored inside the smut gall on the top internodal region of Saccharum spontaneum, a wild relative of sugarcane (Saccharum officinarum). The interactions of spined conidia of S. scitamineum with S. spontaneum were examined during the different stages of plant growth starting from the bud stage to the decaying stage. The spores in the soil from the polyetic inocula grew into confined epidermal cells of the buds and finally sporulated in the topmost internodal region. Hyphae invasion of the plant tissues were restricted to the point of infection. Culms of infected plants in late October sporulated, notably; hyphal sporulation produced shorter hyphal stolons. Remarkably, the nodal regions of infected plants had no spores and fragmented hyphae. On the basis of microscopic analyses, hyphae and spores were absent in all internodes above the ground till the topmost smut gall region. This result indicated that, S. scitamineum undergoes tissue-confined invasion of S. spontaneum. By associating culture medium method with polymerase chain reaction (PCR) on plant portions void of smut gall, S. scitamineum was not detected, indicating that colonization was not systemic. It was observed that the biotrophic interaction resulted in structural reorganization in the restricted region of infection forming erect cylindrical structure, in which the fungus was sandwiched between the central stalk and sheath, and possibly played a key role in preventing inflorescence. Comparatively, a significant difference in the rate of teliospores germination between reference Ustilago esculenta (26.6%, P<0.05) and S. scitamineum (62.9%, P<0.05) at 20° C was observed. This study also provides insights on the effect of different temperature regimes on the germination of S. scitamineum teliospores in vitro. PMID:26642345

  13. Wetland vegetation and nutrient retention in Nakivubo and Kirinya wetlands in the Lake Victoria basin of Uganda

    NASA Astrophysics Data System (ADS)

    Mugisha, P.; Kansiime, F.; Mucunguzi, P.; Kateyo, E.

    Wetlands form an important part of the catchment area of the African Great Lakes and protect water resources therein. One of the most important functions is the retention of nutrients from the inflowing water from the catchment, by wetland plants which store them in their phytomass. An assessment of the capacity in storing nutrients by dominant plants ( Cyeprus papyrus, Miscanthus violaceus, Phragmites mauritianus and Colocasia C. esculenta), of Nakivubo and Kirinya wetlands at the shores of Lake Victoria in Uganda, was studied through the determination of phytomass production and nutrient concentration in the plant parts at different stages of growth. The above ground phytomass production increased rapidly during the exponential growth for C. papyrus and P. mauritianus. In all the dominant plants, nitrogen concentration was highest in juvenile plants and decreased with increasing age. The most pronounced nitrogen level occurred in the young umbels of C. papyrus during the first month of growth with total nitrogen content of 1.95% DW which dropped to 0.62% DW after the fifth month in Nakivubo wetland. Corms (tubers) of yams had the highest nitrogen content in Kirinya and Nakivubo wetlands exhibiting respective values of 4.8% DW and 3.7% DW. There is a close relationship between nutrient content and increase in phytomass. In Nakivubo and Kirinya wetlands, the rapid increase in phytomass during the third and fourth month corresponded with high nutrient levels. Since plants store significant amounts of nitrogen during their growth, periodic harvesting of above ground plant parts can remove significant amounts of nutrients (during the first five months of growth) from the wastewater flowing into the two wetlands. Wetland plant species with high phytomass productivity and well developed root systems and ability to withstand flooding are the best in nutrient removal.

  14. Intra-thallus differentiation of fatty acid and pigment profiles in some temperate Fucales and Laminariales.

    PubMed

    Schmid, Matthias; Stengel, Dagmar B

    2015-02-01

    Intra-thallus variation in fatty acid and pigment contents and profiles was investigated in five species of Laminariales (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Saccharina latissima, and Saccorhiza polyschides), and three Fucales (Ascophyllum nodosum, Fucus serratus, and Himanthalia elongata). Significant variation occurred across all species and compounds examined. Total fatty acids were generally higher in the fronds, with highest levels and largest variability observed in A. nodosum (1.5% of dry weight (DW) in the base, 6.3% of DW in frond tips). Percentages of the omega-3 fatty acids 18:4 n-3 and 20:5 n-3 were generally higher in more distal parts, while 20:4 n-6 exhibited a contrasting pattern, with higher levels in basal structures and holdfasts. Trends for pigments were similar to those for fatty acids in Laminariales. In the Fucales, highest levels were detected in the mid-fronds, with lower concentrations in meristematic areas. Highest levels and greatest variability in pigments (e.g., chl a) was observed in F. serratus (1.07 mg · g(-1) DW in the base, 3.04 mg · g(-1) DW in the mid frond). Intra-thallus variability was attributed to physiological functions of the respective thallus sections, e.g., photosynthetic activity, meristematic tissue, and to variations in physical attributes of the structures investigated. Regarding potential commercial nutritional applications, fronds appeared to represent most suitable source materials, due to higher levels of pigments, polyunsaturated fatty acids, and more preferable omega-3/omega-6 ratios. PMID:26986256

  15. The role of bio-inspired hierarchical structures in wetting.

    PubMed

    Grewal, H S; Cho, Il-Joo; Yoon, Eui-Sung

    2015-04-01

    Superhydrophobicity facilitates the development of self-cleaning, anti-biofouling, and anti-corrosion surfaces. The leaves of the lotus (Nelumbo nucifera) and taro (Colocasia esculenta) plants are well known for their self-cleaning properties. A hierarchical structure comprising papillae epidermal cells superimposed with epicuticular wax crystalloids of varying shapes, sizes, and orientations is an important aspect of the surface of these plant leaves. We fabricated two types of hierarchical structures biomimicking the surface topography of the lotus leaf. The hierarchical patterns successfully demonstrated the superhydrophobic state in comparison with nano and micro patterns. We used the finite element method (FEM) to simulate and understand the wetting process. The FEM simulations showed good correlation with the experimental results. FEM was helpful in understanding the wetting of enormously complex biological surfaces with relative ease, and it qualifies as a potential tool for designing superhydrophobic surfaces. Using the FEM framework, we further designed surfaces to optimize the order of the shapes in hierarchy. The results showed that the superhydrophobic surface with the lowest wetted area was obtained by placing shapes with smaller geometric angles at the top of the hierarchy. This arrangement of shapes provides the optimum combination of superhydrophobicity and surface integrity. This observation explains why the hierarchical structure of many superhydrophobic leaves follows this order. We also investigated the complex hierarchical structure of Salvinia minima. Owing to its remarkable ability to entrap air and pin the contact line, it exhibits superhydrophobicity along with the much-required Cassie state. These properties of Salvinia minima make it an excellent candidate for developing omniphobic surfaces. PMID:25856043

  16. Canopy-Forming Seaweeds in Urchin-Dominated Systems in Eastern Canada: Structuring Forces or Simple Prey for Keystone Grazers?

    PubMed Central

    Blain, Caitlin; Gagnon, Patrick

    2014-01-01

    Models of benthic community dynamics for the extensively studied, shallow rocky ecosystems in eastern Canada emphasize kelp-urchin interactions. These models may bias the perception of factors and processes that structure communities, for they largely overlook the possible contribution of other seaweeds to ecosystem resilience. We examined the persistence of the annual, acidic (H2SO4), brown seaweed Desmarestia viridis in urchin barrens at two sites in Newfoundland (Canada) throughout an entire growth season (February to October). We also compared changes in epifaunal assemblages in D. viridis and other conspicuous canopy-forming seaweeds, the non-acidic conspecific Desmarestia aculeata and kelp Agarum clathratum. We show that D. viridis can form large canopies within the 2-to-8 m depth range that represent a transient community state termed Desmarestia bed. The annual resurgence of Desmarestia beds and continuous occurrence of D. aculeata and A. clathratum, create biological structure for major recruitment pulses in invertebrate and fish assemblages (e.g. from quasi-absent gastropods to >150 000 recruits kg?1 D. viridis). Many of these pulses phase with temperature-driven mass release of acid to the environment and die-off in D. viridis. We demonstrate experimentally that the chemical makeup of D. viridis and A. clathratum helps retard urchin grazing compared to D. aculeata and the highly consumed kelp Alaria esculenta. In light of our findings and related studies, we propose fundamental changes to the study of community shifts in shallow, rocky ecosystems in eastern Canada. In particular, we advocate the need to regard certain canopy-forming seaweeds as structuring forces interfering with top-down processes, rather than simple prey for keystone grazers. We also propose a novel, empirical model of ecological interactions for D. viridis. Overall, our study underscores the importance of studying organisms together with cross-scale environmental variability to better understand the factors and processes that shape marine communities. PMID:24859311

  17. Modification of hosts' behavior by a parasite: field evidence for adaptive manipulation.

    PubMed

    Lagrue, Clment; Kaldonski, Nicolas; Perrot-Minnot, Marie J; Motreuil, Sbastien; Bollache, Loc

    2007-11-01

    Parasites relying on trophic transmission to complete their life cycles often induce modifications of their host's behavior in ways that may increase their susceptibility to predation by final hosts. These modifications have often been interpreted as parasite adaptations, but very few studies have demonstrated that host manipulation has fitness benefits for the parasite. The aim of the present study was to address the adaptive significance of parasite manipulation by coupling observations of behavioral manipulation to estimates of trophic transmission to the definitive host in the natural environment. We show that the acanthocephalan parasite Pomphorhynchus laevis manipulates the drifting behavior of one of its intermediate hosts, the amphipod Gammarus pulex, but not of a sympatric host, the introduced amphipod Gammarus roeseli. We found a 26.3-28.3 times higher proportion of infected G. pulex in the stomach content of one of the definitive hosts of P. laevis, the bullhead Cottus gobio, than in the benthos. No such trend was observed for G. roeseli. The bell-shaped curve of mean parasite abundance (MPA) relative to host size observed in G. pulex also supported an increased predation mortality of P. laevis-infected individuals compared to uninfected amphipods. Again, no such pattern was observed in G. roeseli. Furthermore, our results indicate that the modifications induced by P. laevis are specific to the definitive host and do not increase the risk of predation by inappropriate hosts, here the adult edible frog Rana esculenta. Overall, our study is original in that it establishes, under field conditions, a direct link between parasitic manipulation and increased transmission to the definitive host, and more importantly, identifies the specificity of the manipulation both in the intermediate host species and toward the definitive host. PMID:18051653

  18. The contributions of filaments and cross-bridges to sarcomere compliance in skeletal muscle

    PubMed Central

    Brunello, Elisabetta; Caremani, Marco; Melli, Luca; Linari, Marco; Fernandez-Martinez, Manuel; Narayanan, Theyencheri; Irving, Malcolm; Piazzesi, Gabriella; Lombardi, Vincenzo; Reconditi, Massimo

    2014-01-01

    Force generation in the muscle sarcomere is driven by the head domain of the myosin molecule extending from the thick filament to form cross-bridges with the actin-containing thin filament. Following attachment, a structural working stroke in the head pulls the thin filament towards the centre of the sarcomere, producing, under unloaded conditions, a filament sliding of ∼11 nm. The mechanism of force generation by the myosin head depends on the relationship between cross-bridge force and movement, which is determined by compliances of the cross-bridge (Ccb) and filaments. By measuring the force dependence of the spacing of the high-order myosin- and actin-based X-ray reflections from sartorius muscles of Rana esculenta we find a combined filament compliance (Cf) of 13.1 ± 1.2 nm MPa−1, close to recent estimates from single fibre mechanics (12.8 ± 0.5 nm MPa−1). Ccb calculated using these estimates is 0.37 ± 0.12 nm pN−1, a value fully accounted for by the compliance of the myosin head domain, 0.38 ± 0.06 nm pN−1, obtained from the intensity changes of the 14.5 nm myosin-based X-ray reflection in response to 3 kHz oscillations imposed on single muscle fibres in rigor. Thus, a significant contribution to Ccb from the myosin tail that joins the head to the thick filament is excluded. The low Ccb value indicates that the myosin head generates isometric force by a small sub-step of the 11 nm stroke that drives filament sliding at low load. The implications of these results for the mechanism of force generation by myosins have general relevance for cardiac and non-muscle myosins as well as for skeletal muscle. PMID:25015916

  19. Potential of Trap Crops for Integrated Management of the Tropical Armyworm, Spodoptera litura in Tobacco

    PubMed Central

    Zhou, Zhongshi; Chen, Zepeng; Xu, Zaifu

    2010-01-01

    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. PMID:20874598

  20. PCNA immunoreactivity revealing normal proliferative activity in the brain of adult Lampetra planeri (Bloch, 1784).

    PubMed

    Margotta, Vito; Caronti, Brunella; Colombari, Paolo Tito; Castiglia, Riccardo

    2007-01-01

    It is now well known that the Teleosts among Osteichthyes, Urodele and Anuran Amphibians, Lacertilian Reptiles possess encephalic natural proliferative activities even into adulthood, as demonstrated by a great number of researches performed both under normal and various experimental conditions. Few years ago we have undertaken in adult heterothermic vertebrates a reappraisal on spontaneous cerebral proliferative events involving some organisms (Podarcis sicula, Triturus carnifex, Rana esculenta, Carassius carassius) representative of these vertebrates and belonging to the same or phylogenetically similar species used by previous researchers in studies having the same object. In our investigations, these performances were revealed by a proliferative immunocytochemical marker, the Proliferating Cell Nuclear Antigen (PCNA). At this point of our study in the scenario emerging from findings a missing piece is represented by Petromyzontidae. To fill up this gap in the present investigation, using our usual test, we have paid attention to adult specimens of Lampetra planeri. The obtained immunostaining panorama has revealed the presence of a considerable number of spontaneous proliferative activities. These events might differ in quantity, in various encephalic districts. PCNA-labelled cells appeared scattered in the cranial portion of olfactory bulbs, while the PCNA expression has been observed steadily localized with a distinctly continous distribution in cells interposed among the ependymal epithelium which lines the cavities of the proximal portion of the olfactory region and of the cerebral ventricles. DNA synthesis activity has been also found in cells scattered in the telencephalic, diencephalic, mesencephalic and medulla oblongata periventricular grey. This immunoreactivity was not revealable in the cerebellum. Our findings are discussed in the light of bibliographic news. PMID:17580660

  1. Expression of alpha SM actin in terrestrial ectothermic vertebrates.

    PubMed

    Di Rosa, I; Panara, F; Fagotti, A; Simoncelli, F; Chaponnier, C; Gabbiani, G; Pascolini, R

    1995-09-01

    alpha-Smooth muscle (alpha SM) actin of endothermic vertebrates is selectively recognized by the monoclonal antibody anti-alpha SM-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 their vascular and visceral smooth muscles were stained by anti-alpha SM-1. In all the specimens tested, Western-blot analysis of tissue extracts immunodecorated with anti-alpha SM-1 revealed a single polypeptide chain having the same electrophoretic mobility as bovine alpha SM actin. The binding to amphibian and reptilian tissue extracts was inhibited by the synthetic peptide Ac-EEED, but not Ac-DEED, as occurs in mammals. alpha SM actin expression was found in vascular and visceral smooth muscle cells of the species tested. The media of small and large blood vessels was labelled by anti-alpha SM-1. In the stomach and intestine the outer longitudinal and inner circular layers of the muscularis and of the muscularis mucosae were stained. In addition, myofibroblasts of the subepithelial layer were labelled. A more restricted expression of this isoactin was detected in turtle (P. scripta elegans) visceral smooth muscle cells, which may be related to the involvement of the digestive system in respiratory activity. These data suggest that in vertebrate evolution alpha SM actin arose earlier than previously proposed. PMID:7553770

  2. Cell proliferation and death in the brain of active and hibernating frogs

    PubMed Central

    Cerri, Silvia; Bottiroli, Giovanni; Bottone, Maria Grazia; Barni, Sergio; Bernocchi, Graziella

    2009-01-01

    ‘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. PMID:19531087

  3. Cr(VI) and COD removal from landfill leachate by polyculture constructed wetland at a pilot scale.

    PubMed

    Madera-Parra, C A; Peña, M R; Peña, E J; Lens, P N L

    2015-09-01

    Four subsurface horizontal-flow constructed wetlands (CWs) at a pilot scale planted with a polyculture of the tropical plants Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) were evaluated for 7 months. The CW cells with an area of 17.94 m(2) and 0.60 m (h) each and 0.5 m of gravel were operated at continuous gravity flow (Q = 0.5 m(3) day(-1)) and a theoretical HRT of 7 days each and treating landfill leachate for the removal of filtered chemical oxygen demand (CODf), BOD5, TKN, NH4 (+), NO3 (-), PO4 (3-)-P and Cr(VI). Three CWs were divided into three sections, and each section (5.98 m(2)) was seeded with 36 cuttings of each species (plant density of six cuttings per square metre). The other unit was planted randomly. The final distributions of plants in the bioreactors were as follows: CW I (He-Ce-Gs), CW II (randomly), CW III (Ce-Gs-He) and CW IV (Gs-He-Ce). The units received effluent from a high-rate anaerobic pond (BLAAT®). The results show a slightly alkaline and anoxic environment in the solid-liquid matrix (pH = 8.0; 0.5-2 mg L(-1) dissolved oxygen (DO)). CODf removal was 67 %, BOD5 80 %, and TKN and NH4 (+) 50-57 %; NO3 (-) effluents were slightly higher than the influent, PO4 (3-)-P (38 %) and Cr(VI) between 50 and 58 %. CW IV gave the best performance, indicating that plant distribution may affect the removal capacity of the bioreactors. He and Gs were the plants exhibiting a translocation factor (TF) of Cr(VI) >1. The evaluated plants demonstrated their suitability for phytoremediation of landfill leachate, and all of them can be categorized as Cr(VI) accumulators. The CWs also showed that they could be a low-cost operation as a secondary system for treatment of intermediated landfill leachate (LL). PMID:25253061

  4. Comparative assessment of the value of papyrus and cocoyams for the restoration of the Nakivubo wetland in Kampala, Uganda

    NASA Astrophysics Data System (ADS)

    Kansiime, F.; Oryem-Origa, H.; Rukwago, S.

    Nakivubo wetland, located on the northern shores of Lake Victoria, separates the city of Kampala from the Inner Murchison Bay of Lake Victoria (the sole raw water supply for Kampala). It provides tertiary treatment for the secondary effluent from the Bugolobi sewage treatment works, and heavily polluted wastewater (run-off, domestic and industrial effluents) from the Nakivubo channel. However, more than half of the wetland has been drained for agriculture and the natural papyrus vegetation ( Cyperus papyrus) has been progressively replaced by cocoyams ( Colocasia esculenta). In order to provide information that could be used in the restoration of Nakivubo wetland, a pilot study was carried out to assess the ecological characteristics (nutrient retention and growth characteristics) of the two plants. The plants were grown in wastewater effluent from the Bugolobi sewage treatment works, in experimental buckets under floating and rooted conditions. The wastewater was replaced every seven days. Papyrus plants were more efficient at removing NH 4-N while growing floating in wastewater or rooted in gravel (maximum values being 89.4% and 79%, respectively) than were cocoyams (67.7% and 68.3%) or the controls without plants (11% and 9%, respectively). The removal of orthophosphate by papyrus was also greater under the two growing conditions (values being 80% and 73%) than by cocoyams (66% and 63%) or the controls (11% and 14%). Biomass densities of papyrus were also higher (16.9 kg Dw/m 2 for the floating plants and 18.7 kg Dw/m 2 for the rooted ones) than of yams (5.9 kg DW/m 2 and 6.8 kg DW/m 2, respectively). It was also observed that the rhizomes of yams did not develop well under the floating conditions and were often rotten. It is concluded that, since papyrus has better wastewater treatment efficiency and superior growth characteristics, it should be encouraged to grow again in the wetland. It was also noted that if encroachment of the wetland by agricultural activities is halted, papyrus would eventually out-compete the yams. Keeping Nakivubo wetland inundated would offer papyrus a competitive advantage, since yams grow poorly when floating in water.

  5. Natural pesticides and bioactive components in foods.

    PubMed

    Beier, R C

    1990-01-01

    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

  6. Implications of agricultural encroachment on the carbon and greenhouse gas dynamics in tropical African wetlands.

    NASA Astrophysics Data System (ADS)

    Saunders, Matthew; Kansiime, Frank; Jones, Michael

    2015-04-01

    Cyperus papyrus L. (papyrus) wetlands dominate the permanently inundated wetlands of tropical East Africa and support the livelihoods of millions of people in rural sub-Saharan Africa through the provision of multiple ecosystem services such as the supply of drinking water, fish protein, building materials and biofuels. These wetlands are also extremely important in local and regional scale biogeochemical cycles due to their extensive spatial distribution, high rates of photosynthetic carbon dioxide (CO2) assimilation, long-term carbon (C) sequestration in the form of peat and the control of water loss through evapotranspiration. However, these wetlands are facing significant anthropogenic pressures due to the increasing demand for agricultural land where the papyrus plants are removed and replaced with subsistence crops such as cocoyam (Colocasia esculenta). Eddy covariance measurements were made on an undisturbed papyrus wetland and a cocoyam dominated wetland on the Ugandan shoreline of Lake Victoria to better understand the impacts of agricultural encroachment on the C sequestration potential of these wetlands. Peak rates of net photosynthetic CO2 assimilation at the papyrus wetland were over 40 μmol CO2 m-2 s-1, even under increasing vapour pressure deficit (≥2 kPa), while maximum rates of assimilation at the cocoyam site were 28 μmol CO2 m-2 s-1. Annual rates of papyrus net primary productivity (NPP) were amongst the highest recorded for wetland systems globally (3.09 kg C m-2 yr-1) and the continual regeneration of the papyrus plants, due to an absence of pronounced seasonal climatic variability, can lead to significant C accumulation in the above and belowground biomass (≥88 t C ha-1). Where these wetlands remain inundated and anaerobic conditions prevail, significant detrital and peat deposits can form further increasing the combined C sink capacity of these ecosystems to over 700 t C ha-1. The C sink strength of these wetlands is however offset by the production and emission of methane (CH4), and plant-facilitated emissions of up to 32 mg CH4 m-2 h-1 were measured from mature papyrus plants grown in a constructed wetland, suggesting that these wetlands may make a significant contribution to regional methane emissions. The conversion of the papyrus wetlands to agricultural land use has significant implications for the carbon budgets of these systems, as the decomposition of detrital material in addition to the carbon exported in the crop biomass resulted in a net loss of carbon of ~10 t C ha-1 yr-1. The development of sustainable wetland management strategies are therefore required to maintain and enhance the services provided by these ecosystems especially under increasing population pressures and future climatic scenarios.

  7. Quantifying Nitrogen Loss From Flooded Hawaiian Taro Fields

    NASA Astrophysics Data System (ADS)

    Deenik, J. L.; Penton, C. R.; Bruland, G. L.; Popp, B. N.; Engstrom, P.; Mueller, J. A.; Tiedje, J.

    2010-12-01

    In 2004 a field fertilization experiment showed that approximately 80% of the fertilizer nitrogen (N) added to flooded Hawaiian taro (Colocasia esculenta) fields could not be accounted for using classic N balance calculations. To quantify N loss through denitrification and anaerobic ammonium oxidation (anammox) pathways in these taro systems we utilized a slurry-based isotope pairing technique (IPT). Measured nitrification rates and porewater N profiles were also used to model ammonium and nitrate fluxes through the top 10 cm of soil. Quantitative PCR of nitrogen cycling functional genes was used to correlate porewater N dynamics with potential microbial activity. Rates of denitrification calculated using porewater profiles were compared to those obtained using the slurry method. Potential denitrification rates of surficial sediments obtained with the slurry method were found to drastically overestimate the calculated in-situ rates. The largest discrepancies were present in fields greater than one month after initial fertilization, reflecting a microbial community poised to denitrify the initial N pulse. Potential surficial nitrification rates varied between 1.3% of the slurry-measured denitrification potential in a heavily-fertilized site to 100% in an unfertilized site. Compared to the use of urea, fish bone meal fertilizer use resulted in decreased N loss through denitrification in the surface sediment, according to both porewater modeling and IPT measurements. In addition, sub-surface porewater profiles point to root-mediated coupled nitrification/denitrification as a potential N loss pathway that is not captured in surface-based incubations. Profile-based surface plus subsurface coupled nitrification/denitrification estimates were between 1.1 and 12.7 times denitrification estimates from the surface only. These results suggest that the use of a ‘classic’ isotope pairing technique that employs 15NO3- in fertilized agricultural systems can lead to a drastic overestimation of in-situ denitrification rates and that root-associated subsurface coupled nitrification/denitrification may be a major N loss pathway in these flooded agricultural systems.

  8. 2000 years of sustainable use of watersheds and coral reefs in Pacific Islands: A review for Palau

    NASA Astrophysics Data System (ADS)

    Koshiba, Shirley; Besebes, Meked; Soaladaob, Kiblas; Ngiraingas, Madelsar; Isechal, Adelle Lukes; Victor, Steven; Golbuu, Yimnang

    2014-05-01

    In Palau and everywhere in the world, coastal coral reefs are threatened by sedimentation resulting from land clearing in the watersheds. Palau's largest island of Babeldaob is particularly susceptible to significant erosion due to its steep topography, high rainfall, and highly erodible volcanic soil. Previous studies have shown the damaging impacts of sedimentation on coral reefs around Babeldaob Island. Related studies conducted in Micronesia have also documented that mangroves can trap about 30% of the fine eroded sediment from land. This paper examines the sediment trapping capability of cultivated wetlands, in particular taro (Colocasia esculenta) fields, which are natural wetlands used to grow taro, a main staple crop for the population. A 7-months long field study was undertaken to quantify the sediment accumulation rate for taro fields and to determine their sediment trapping efficiency. The results showed that the taro fields were able to trap on average 90% of sediment, therefore sheltering coastal coral reefs and their fisheries from the negative impacts of terrestrial runoff. Based on the results of this study, we suggest that the combined sediment trapping capacity of taro fields and mangroves helped reduce sedimentation on coral reefs around Babeldaob Island. This enabled human settlement for over 2000 years on a small Pacific Island with the main staple food being taro for starch and reef fish for protein. Even with a population of 30,000 people over Babeldaob Island, the living was sustainable for at least 1000 years, implying that the population was able to survive and prosper with its main food being the starch from taro fields and protein from reef fish. While there was intensive cultivation on land the sustainability of reef fisheries must have required that the reef be sheltered from excessive soil erosion.The structure of the taro field (mesei) initialized by the Palauan ancestors, has been maintained to this day. Their development, probably mostly after about A.D. 900 to 1100, was presumably the culmination of accelerated erosion in the island's interior following extensive clearing of the vegetation on slopes. Sediment analyses, radiocarbon dating, and archaeological investigations indicate substantial inland land disturbance starting around 2400 years ago (Liston and Tuggle, 2006; Liston, 2009). These findings almost certainly signify the use of the interior of Babeldaob Island by this time, including the onset of major earthwork (terrace) construction. Intensive and extensive inland use continued for about another 1200 years. The continuous deposition of inland erosional soils expanded the coastal plains and formed expansive fertile wetlands” (Athens, 2009).Culturally in Palau taro fields were tendered by women (Del Rosario and Esguerra, 2003). In other parts of Micronesia, taro is planted in well drained mixed gardens or ditches (Falanruw, 1980; Englberger et al., 2009). In Palau taro is commonly grown in swampy areas, often man-made, in the lowlands usually just upstream of the mangrove areas. Traditional management of taro cultivation in Palau can be considered a type of intensive agricultural method found in societies that possess a complex social structure that is reflected in traditional Palauan society. Taro cultivation in Palau is an amalgamation of skills and knowledge for both the plant and agricultural system.Palau taro field structure, regulations of water flow and management have persisted for many generations and have proven to an integral part of Palauan life which continues to be seen today. Taro fields are distinguished separately depending on cultivation methods and taro species being planted. To illustrate, an omrekongel is a marsh land in which giant taro (Cyrtosperma merkusii) is planted. A mesei is an irrigated wet land for planting taro (Colocasia esculenta) and dechel is a marsh land where taro and giant taro is cultivated (Palau Society of Historians, 2001). Culturally, Cyrtosperma is treated as a food source for famine where it has high resistance to saltwater and longer plant life (3-5 years); it's a rich source of starch in times of droughts and other natural disaster. Colocasia, on the other hand, is viewed as prestigious source of food in Palau. Whereas Cyrtosperma requires little tending once it has been planted Colocasia is more delicate for its fragility and shorter plant life (8-12 months). Therefore more efforts are spent tending Colocasia than Cyrtosperma (McKnight and Obak, 1960; Bammann and Wey, 1991). Although both are eaten quite often, Colocasia can be found in many aspects of Palauan cultural practices (funerals, first birth ceremonies, transfer of title ceremonies) and used symbolically in chants, dances, proverbs, and stories with moral lessons (Palau Society of Historians, 2008).

  9. The effect of the benzothiazepine diltiazem on force and Ca2+ current in isolated frog skeletal muscle fibres.

    PubMed Central

    Böhle, T

    1992-01-01

    1. The action of the D-cis and L-cis isomers of the benzothiazepine derivative diltiazem on isometric force and L-type Ca2+ inward current in short muscle fibres from toe muscles of the frog (Rana esculenta and R. temporaria) was investigated under voltage clamp control with two internal microelectrodes. The experiments were performed at 10 degrees C in TEA-sulphate solution, in which the concentration of ionized Ca2+ was about 4 mM. 2. In the presence of diltiazem (D-cis, 0.25-30 microM; L-cis, 5-100 microM) normal Ca2+ currents and phasic contractures could be elicited by a depolarizing voltage step. However, after long-lasting depolarizations both the Ca2+ channel and the force controlling system (voltage sensor) remained refractory for minutes instead of seconds as under control conditions, i.e. they were 'paralysed'. L-cis diltiazem was about 20 times less effective in comparison with the D-cis isomer. 3. Speed of restoration of force and Ca2+ current was retarded by up to two orders of magnitude, depending on the applied concentration of diltiazem. 4. The steady state potential dependence of force restoration (V0.5 = -49 mV; the potential at which half of the voltage sensors are restored) and that of Ca2+ current restoration (V0.5 = -57 mV) were not altered by diltiazem. 5. The time course of the transition to paralysis, which was quite slow under control conditions, could be accelerated by diltiazem in a concentration-dependent manner. 6. Paralysis developed at the same speed when the fibre was depolarized from -90 mV to -30 mV or to +30 mV. 7. The voltage dependence of Ca2+ current inactivation (inactivation curve; conditioning pulses of 2 min duration) was shifted by about 14 mV to more negative potentials (V0.5 = -31 mV; V'0.5 = -45 mV) under the influence of 1 microM-D-cis diltiazem. It is assumed that no steady state was reached during the conditioning pulse. 8. The voltage dependence of force activation (V0.5 = -45 mV) was not altered by diltiazem. 9. Since the effects of both isomers of diltiazem could only be disclosed during the adjustment of a new steady state and since the drugs acted in a similar way on the inactivation kinetics of force and Ca2+ current, it is concluded that, in depolarized fibres, the drug facilitates the transition to a stabilized inactivated form of the voltage sensor/Ca2+ channel molecule. PMID:1323667

  10. Energy transfer during stress relaxation of contracting frog muscle fibres

    PubMed Central

    Mantovani, M; Heglund, N C; Cavagna, G A

    2001-01-01

    A contracting muscle resists stretching with a force greater than the force it can exert at a constant length, To. If the muscle is kept active at the stretched length, the excess tension disappears, at first rapidly and then more slowly (stress relaxation). The present study is concerned with the first, fast tension decay. In particular, it is still debated if and to what extent the fast tension decay after a ramp stretch involves a conservation of the elastic energy stored during stretching into cross-bridge states of higher chemical energy. Single muscle fibres of Rana temporaria and Rana esculenta were subjected to a short ramp stretch (∼15 nm per half-sarcomere at either 1.4 or 0.04 sarcomere lengths s−1) on the plateau of the force-length relation at temperatures of 4 and 14°C. Immediately after the end of the stretch, or after discrete time intervals of fixed-end contraction and stress relaxation at the stretched length (Δtisom= 0.5–300 ms), the fibre was released against a force ∼To. Fibre and sarcomere stiffness during the elastic recoil to To (phase 1) and the subsequent transient shortening against To (phase 2), which is expression of the work enhancement by stretch, were measured after different Δtisom and compared with the corresponding fast tension decay during Δtisom. The amplitude of fast tension decay is large after the fast stretch, and small or nil after the slow stretch. Two exponential terms are necessary to fit the fast tension decay after the fast stretch at 4°C, whereas one is sufficient in the other cases. The rate constant of the dominant exponential term (0.1–0.2 ms−1 at 4°C) increases with temperature with a temperature coefficient (Q10) of ∼3. After fast stretch, the fast tension decay during Δtisom is accompanied in both species and at both temperatures by a corresponding increase in the amplitude of phase 2 shortening against To after Δtisom: a maximum of ∼5 nm per half-sarcomere is attained when the fast tension decay is almost complete, i.e. 30 ms after the stretch at 4°C and 10 ms after the stretch at 14°C. After slow stretch, when fast tension decay is small or nil, the increase in phase 2 shortening is negligible. The increase in phase 2 work during fast tension decay (ΔWout) is a constant fraction of the elastic energy simultaneously set free by the recoil of the undamped elastic elements. ΔWout is accompanied by a decrease in stiffness, indicating that it is not due to a greater number of cross-bridges. It is concluded that, during the fast tension decay following a fast ramp stretch, a transfer of energy occurs from the undamped elastic elements to damped elements within the sarcomeres by a temperature-dependent mechanism with a dominant rate constant consistent with the theory proposed by A. F. Huxley and R. M. Simmons in 1971. PMID:11744765

  11. Use of Novel Whole Core Incubations to Measure the Fate of Fertilizer N in a Flooded Agricultural System

    NASA Astrophysics Data System (ADS)

    Penton, C. R.; Bruland, G. L.; Popp, B. N.; Engstrom, P.; Tiedje, J.; Brown, G. A.; Deenik, J. L.

    2010-12-01

    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.