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Sample records for 19-iodo cholesterol-125i 3-acetate

  1. A comparative study of 19-iodo cholesterol-125I 3-acetate and Na 125I in liquid scintillation measurements; Estudio comparativo del acetato de 19-iodocolesterol- -125I con Nal25I en medidas por centelleo liquido

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Barquero, L.; Grau Malonda, A.; Los Arcos Merino, J. M.; Grau Carles, A.

    1994-07-01

    A comparative study of performance of 19-iodo cholesterol {sup 1}25I 3-acetate and sodium iodide samples labeled with 125I is presented for liquid scintillation counting measurements. Quench effect, count rate stability and spectral evolution of samples have been followed for several weeks in Toluene, Hisafe II, Instagel, Dioxane-naphthalene and Toluene-alcohol scintillators. Organic samples have negligible quench effect in the interval of I concentration of 0-90 {mu}g and inorganic samples only show a very small variation, lower than 12%, for Dioxane-naphthalene, in the same range of concentration. Satisfactory stability is obtained in general for both, organic and inorganic samples, but small counting losses, 0.03% for 19-iodocholesterol 1 I 3-acetate samples in Tolue ne-alcohol and 0 .04% for Na 125I samples in Dioxane-naphthalene and Toluene-alcohol, have been reported. (Author) 8 refs.

  2. Preparation of 19-iodo cholesterol labelled with 125 I; Preparacion del 19-yodocolesterol marcado con 125 I

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L.; Rebollo, D. V.; Ruiz, J. M.

    1986-07-01

    In this paper a new method of synthesis of 19-iodo cholesterol labelled with ''125 I, from commercial cholesterol, is described. Its high chemical (96%) and radiochemical (99.9%) purities high yield and short time of preparation permit us to dispose or a more accessible labelled compound, which results appropriates for clinical investigations and in the diagnosis of disturbances of the suprarenal glands. (Author) 9 refs.

  3. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by an enzyme preparation from Zea mays

    Science.gov (United States)

    Reinecke, D. M.; Bandurski, R. S.

    1988-01-01

    Indole-3-acetic acid is oxidized to oxindole-3-acetic acid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-acetic acid to oxindole-3-acetic acid in higher plants.

  4. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by an enzyme preparation from Zea mays

    Science.gov (United States)

    Reinecke, D. M.; Bandurski, R. S.

    1988-01-01

    Indole-3-acetic acid is oxidized to oxindole-3-acetic acid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-acetic acid to oxindole-3-acetic acid in higher plants.

  5. Measurement of the rates of oxindole-3-acetic acid turnover, and indole-3-acetic acid oxidation in Zea mays seedlings

    Science.gov (United States)

    Nonhebel, H. M.; Bandurski, R. S. (Principal Investigator)

    1986-01-01

    Oxindole-3-acetic acid is the principal catabolite of indole-3-acetic acid in Zea mays seedlings. In this paper measurements of the turnover of oxindole-3-acetic acid are presented and used to calculate the rate of indole-3-acetic acid oxidation. [3H]Oxindole-3-acetic acid was applied to the endosperm of Zea mays seedlings and allowed to equilibrate for 24 h before the start of the experiment. The subsequent decrease in its specific activity was used to calculate the turnover rate. The average half-life of oxindole-3-acetic acid in the shoots was found to be 30 h while that in the kernels had an average half-life of 35h. Using previously published values of the pool sizes of oxindole-3-acetic acid in shoots and kernels from seedlings of the same age and variety, and grown under the same conditions, the rate of indole-3-acetic acid oxidation was calculated to be 1.1 pmol plant-1 h-1 in the shoots and 7.1 pmol plant-1 h-1 in the kernels.

  6. Oxidation of indole-3-acetic acid and oxindole-3-acetic acid to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glucopyranoside in Zea mays seedlings

    Science.gov (United States)

    Nonhebel, H. M.; Bandurski, R. S.

    1984-01-01

    Radiolabeled oxindole-3-acetic acid was metabolized by roots, shoots, and caryopses of dark grown Zea mays seedlings to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glycopyranoside with the simpler name of 7-hydroxyoxindole-3-acetic acid-glucoside. This compound was also formed from labeled indole-3-acetic acid supplied to intact seedlings and root segments. The glucoside of 7-hydroxyoxindole-3-acetic acid was also isolated as an endogenous compound in the caryopses and shoots of 4-day-old seedlings. It accumulates to a level of 4.8 nanomoles per plant in the kernel, more than 10 times the amount of oxindole-3-acetic acid. In the shoot it is present at levels comparable to that of oxindole-3-acetic acid and indole-3-acetic acid (62 picomoles per shoot). We conclude that 7-hydroxyoxindole-3-acetic acid-glucoside is a natural metabolite of indole-3-acetic acid in Z. mays seedlings. From the data presented in this paper and in previous work, we propose the following route as the principal catabolic pathway for indole-3-acetic acid in Zea seedlings: Indole-3-acetic acid --> Oxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid-glucoside.

  7. Oxidation of indole-3-acetic acid and oxindole-3-acetic acid to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glucopyranoside in Zea mays seedlings

    Science.gov (United States)

    Nonhebel, H. M.; Bandurski, R. S.

    1984-01-01

    Radiolabeled oxindole-3-acetic acid was metabolized by roots, shoots, and caryopses of dark grown Zea mays seedlings to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glycopyranoside with the simpler name of 7-hydroxyoxindole-3-acetic acid-glucoside. This compound was also formed from labeled indole-3-acetic acid supplied to intact seedlings and root segments. The glucoside of 7-hydroxyoxindole-3-acetic acid was also isolated as an endogenous compound in the caryopses and shoots of 4-day-old seedlings. It accumulates to a level of 4.8 nanomoles per plant in the kernel, more than 10 times the amount of oxindole-3-acetic acid. In the shoot it is present at levels comparable to that of oxindole-3-acetic acid and indole-3-acetic acid (62 picomoles per shoot). We conclude that 7-hydroxyoxindole-3-acetic acid-glucoside is a natural metabolite of indole-3-acetic acid in Z. mays seedlings. From the data presented in this paper and in previous work, we propose the following route as the principal catabolic pathway for indole-3-acetic acid in Zea seedlings: Indole-3-acetic acid --> Oxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid-glucoside.

  8. Catabolism of indole-3-acetic acid and 4- and 5-chloroindole-3-acetic acid in Bradyrhizobium japonicum

    DEFF Research Database (Denmark)

    Jensen, J B; Egsgaard, H; Van Onckelen, H

    1995-01-01

    Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid. Indoleacetic acid (IAA), 4-chloro-IAA (4-Cl-IAA), and 5-Cl-IAA were metabolized to different extents by strains 61A24 and 110. Metabolites were isolated and analyzed by high-performance liquid chromatogr...

  9. Catabolism of indole-3-acetic acid and 4- and 5-chloroindole-3-acetic acid in Bradyrhizobium japonicum

    DEFF Research Database (Denmark)

    Jensen, J B; Egsgaard, H; Van Onckelen, H

    1995-01-01

    Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid. Indoleacetic acid (IAA), 4-chloro-IAA (4-Cl-IAA), and 5-Cl-IAA were metabolized to different extents by strains 61A24 and 110. Metabolites were isolated and analyzed by high-performance liquid...... chromatography and conventional mass spectrometry (MS) methods, including MS-mass spectroscopy, UV spectroscopy, and high-performance liquid chromatography-MS. The identified products indicate a novel metabolic pathway in which IAA is metabolized via dioxindole-3-acetic acid, dioxindole, isatin, and 2......-aminophenyl glyoxylic acid (isatinic acid) to anthranilic acid, which is further metabolized. Degradation of 4-Cl-IAA apparently stops at the 4-Cl-dioxindole step in contrast to 5-Cl-IAA which is metabolized to 5-Cl-anthranilic acid. Udgivelsesdato: 1995-Oct...

  10. Occurrence and metabolism of 7-hydroxy-2-indolinone-3-acetic acid in Zea mays

    Science.gov (United States)

    Lewer, P.; Bandurski, R. S.

    1987-01-01

    7-Hydroxy-2-indolinone-3-acetic acid was identified as a catabolite of indole-3-acetic acid in germinating kernels of Zea mays and found to be present in amounts of ca 3.1 nmol/kernel. 7-Hydroxy-2-indolinone-3-acetic acid was shown to be a biosynthetic intermediate between 2-indolinone-3-acetic acid and 7-hydroxy-2-indolinone-3-acetic acid-7'-O-glucoside in both kernels and roots of Zea mays. Further metabolism of 7-hydroxy-2-[5-3H]-indolinone-3-acetic acid-7'-O-glucoside occurred to yield tritiated water plus, as yet, uncharacterized products.

  11. Metabolic regulation of the plant hormone indole-3-acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Jerry D. Cohen

    2009-11-01

    The phytohormone indole-3-acetic acid (IAA, auxin) is important for many aspects of plant growth, development and responses to the environment yet the routes to is biosynthesis and mechanisms for regulation of IAA levels remain important research questions. A critical issue concerning the biosynthesis if IAA in plants is that redundant pathways for IAA biosynthesis exist in plants. We showed that these redundant pathways and their relative contribution to net IAA production are under both developmental and environmental control. We worked on three fundamental problems related to how plants get their IAA: 1) An in vitro biochemical approach was used to define the tryptophan dependent pathway to IAA using maize endosperm, where relatively large amounts of IAA are produced over a short developmental period. Both a stable isotope dilution and a protein MS approach were used to identify intermediates and enzymes in the reactions. 2) We developed an in vitro system for analysis of tryptophan-independent IAA biosynthesis in maize seedlings and we used a metabolite profiling approach to isolate intermediates in this reaction. 3) Arabidopsis contains a small family of genes that encode potential indolepyruvate decarboxylase enzymes. We cloned these genes and studied plants that are mutant in these genes and that over-express each member in the family in terms of the level and route of IAA biosynthesis. Together, these allowed further development of a comprehensive picture of the pathways and regulatory components that are involved in IAA homeostasis in higher plants.

  12. Antimicrobial activity of rhodanine-3-acetic acid derivatives.

    Science.gov (United States)

    Krátký, Martin; Vinšová, Jarmila; Stolaříková, Jiřina

    2017-03-15

    Twenty-four 2-(4-oxo-2-thioxothiazolidin-3-yl)acetic acid (rhodanine-3-acetic acid)-based amides, esters and 5-arylalkylidene derivatives were synthesized, characterized and evaluated as potential antimicrobial agents against a panel of bacteria, mycobacteria and fungi. All of the derivatives were active against mycobacteria. N-(4-Chlorophenyl)-2-[5-(2-hydroxybenzylidene)-4-oxo-2-thioxothiazolidin-3-yl]acetamide demonstrated the highest activity against Mycobacterium tuberculosis with minimum inhibitory concentrations (MIC) of 8-16μM. Non-tuberculous mycobacteria were the most susceptible to 2-[5-(2-hydroxybenzylidene)-4-oxo-2-thioxothiazolidin-3-yl]acetic acids (MIC values ⩾32μM). The highest antibacterial activity against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus exhibited 4-(trifluoromethyl)phenyl 2-(4-oxo-2-thioxothiazolidin-3-yl)acetate (MIC⩾15.62μM). Several structure-activity relationships were identified. The activity against Gram-negative and fungal pathogens was marginal. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Indole-3-acetic acid metabolism in normal and dwarf micropropagated banana plants (Musa spp. AAA)

    OpenAIRE

    Zaffari,Gilmar Roberto; Peres,Lázaro Eustáquio Pereira; Tcacenco,Fernando Adami; Kerbauy,Gilberto Barbante

    2002-01-01

    Nanism is one of the most frequent type of mutant in micropropagated banana plants from the Cavendish subgroup. The present study aimed at studying some of the hormone factors involved in this type of mutation. Rhizomes from normal and dwarf plants from the cultivar Grand Naine were incubated for 5 d in the presence of [³H]-L-tryptophan, [³H]-indole-3-acetic acid and gibberellin, to quantify the endogenous levels of indole-3-acetic acid-ester, indole-3-acetic acid-amide, free indole-3-acetic ...

  14. myo-Inositol 1,3-acetals as early intermediates during the synthesis of cyclitol derivatives.

    Science.gov (United States)

    Gurale, Bharat P; Sardessai, Richa S; Shashidhar, Mysore S

    2014-11-18

    Synthetic sequences starting from commercially available myo-inositol necessarily involve protection-deprotection strategies of its six hydroxyl groups. Several strategies have been developed/attempted over the last several decades leading to the synthesis of naturally occurring phosphoinositols, their analogs, and cyclitol derivatives. Of late, myo-inositol 1,3-acetals, which can be obtained by the reductive cleavage of myo-inositol orthoesters have emerged as early intermediates for the synthesis of phosphorylated and other inositol derivatives. This mini-review is an attempt to illustrate the economy and convenience of using myo-inositol 1,3-acetals as early intermediates during syntheses from myo-inositol.

  15. Oxygen-dependent catabolism of indole-3-acetic acid in Bradyrhizobium japonicum

    DEFF Research Database (Denmark)

    Egebo, L A; Nielsen, S V; Jochimsen, B U

    1991-01-01

    Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid (IAA). Examination of this catabolism in strain 110 by in vivo experiments has revealed an enzymatic activity catalyzing the degradation of IAA and 5-hydroxy-indole-3-acetic acid. The activity requires...... an oxygen-consuming opening of the indole ring analogous to the one catalyzed by tryptophan 2,3-dioxygenase. The pattern of metabolite usage by known tryptophan-auxotrophic mutants and studies of metabolites by high-performance liquid chromatography indicate that anthranilic acid is a terminal degradation...

  16. Determination of 4-Chloroindole-3-Acetic Acid Methyl Ester in Lathyrus Vicia and Pisum by Gas Chromatography - Mass Spectrometry

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen; Egsgaard, Helge; Larsen, Elfinn

    1980-01-01

    4-Chloroindole-3-acetic acid methyl ester was identified unequivocally in Lathyrus latifolius L., Vicia faba L. and Pisum sativum L. by thin layer chromatography, gas chromatography and mass spectrometry. The gas chromatographic system was able to separate underivatized chloroindole-3-acetic acid...... methyl ester isomers. The quantitative determination of 4-chloroindole-3-acetic acid methyl ester in immature seeds of these three species was performed by gas chromatography – mass spectrometry using deuterium labelled 4-chloro-indole-3-acetic acid methyl ester as an internal standard. P. sativum...

  17. Isolation and characterization of esters of indole-3-acetic acid from the liquid endosperm of the horse chestnut (Aesculus species)

    Science.gov (United States)

    Domagalski, W.; Schulze, A.; Bandurski, R. S.

    1987-01-01

    Esters of indole-3-acetic acid were extracted and purified from the liquid endosperm of immature fruits of various species of the horse chestnut (Aesculus parviflora, A. baumanni, A. pavia rubra, and A. pavia humulis). The liquid endosperm contained, at least 12 chromatographically distinct esters. One of these compounds was purified and characterized as an ester of indole-3-acetic acid and myo-inositol. A second compound was found to be an ester of indole-3-acetic acid and the disaccharide rutinose (glucosyl-rhamnose). A third compound was partially characterized as an ester of indole-3-acetic acid and a desoxyaminohexose.

  18. Chloroindolyl-3-acetic Acid and its Methyl Ester Incorporation of 36Cl in Immature Seeds of Pea and Barley

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1974-01-01

    compounds besides Cl−. One compound, present in pea and probably in barley, cochromatographed with a mixture of 4- and 6-chloroindolyl-3-acetic acid methyl esters. Another, detected in pea, but probably not in barley, cochromatographed with a mixture of 4-and 6-chloroindolyl-3-acetic acids....

  19. Endohyphal Bacterium Enhances Production of Indole-3-Acetic Acid by a Foliar Fungal Endophyte

    OpenAIRE

    Hoffman, Michele T.; Gunatilaka, Malkanthi K.; Kithsiri Wijeratne; Leslie Gunatilaka; A Elizabeth Arnold

    2013-01-01

    Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have ...

  20. Indole-3-Acetic Acid Biosynthesis in the Mutant Maize orange pericarp, a Tryptophan Auxotroph.

    Science.gov (United States)

    Wright, A D; Sampson, M B; Neuffer, M G; Michalczuk, L; Slovin, J P; Cohen, J D

    1991-11-15

    The maize mutant orange pericarp is a tryptophan auxotroph, which results from mutation of two unlinked loci of tryptophan synthase B. This mutant was used to test the hypothesis that tryptophan is the precursor to the plant hormone indole-3-acetic acid (IAA). Total IAA in aseptically grown mutant seedlings was 50 times greater than in normal seedlings. In mutant seedlings grown on media containing stable isotopelabeled precursors, IAA was more enriched than was tryptophan. No incorporation of label into IAA from tryptophan could be detected. These results establish that IAA can be produced de novo without tryptophan as an intermediate.

  1. Potential antibacterial activity of coumarin and coumarin-3-acetic acid derivatives.

    Science.gov (United States)

    Chattha, Fauzia Anjum; Munawar, Munawar Ali; Nisa, Mehrun; Ashraf, Mohammad; Kousar, Samina; Arshad, Shafia

    2015-05-01

    Coumarin and coumarin-3-acetic acid derivatives were synthesized by reacting phenols with malic acid, ethyl acetoacetate and ethyl acetylsuccinate in appropriate reaction conditions. All synthesized compounds were subjected to test for their antimicrobial activities against variety of gram positive (Bacillus subtilis, Staphylococcus aureus) and gram negative bacterial stains (Shigella sonnei, Escherichia coli) by agar dilution method. Several of them exhibited appreciable good antibacterial activity against the different strains of gram positive and gram negative bacteria. These findings suggest a great potential of these compounds for screening and use as antibacterial agents for further studies with a battery of bacteria.

  2. Primary Action of Indole-3-acetic Acid in Crown Gall Tumors: Increase of Solute Uptake.

    Science.gov (United States)

    Rausch, T; Kahl, G; Hilgenberg, W

    1984-06-01

    Exogenously added indole-3-acetic acid at a concentration of 100 micromolars stimulates d-glucose uptake (or 3-O-methyl-d-glucose uptake) by 25% in crown gall tumors induced on potato tuber tissue by Agrobacterium tumefaciens strain C 58. The titration of the endogenous IAA with the auxin antagonist 2-naphthaleneacetic acid at 100 micromolars reduces d-glucose uptake by about 80%. The apparent inhibition constant K(i) is 21 micromolars. Other auxin antagonists like 1-naphthoxyacetic acid and 2-(p-chlorophenoxy)-2-methylpropionic acid show similar effects. The uptake of the amino acids leucine, methionine, tryptophan, lysine, and aspartic acid is also inhibited by 2-naphthaleneacetic acid to similar degrees. The auxins 1-naphthaleneacetic acid and 2-naphthoxyacetic acid at concentrations between 10 and 100 micromolars inhibit solute uptake only slightly (inhibition less than 20%). The impact of the results on the postulated role of indole-3-acetic acid as a modifier of the electrochemical proton gradient across the plasmalemma in crown gall tumor tissue is discussed.

  3. Primary Action of Indole-3-acetic Acid in Crown Gall Tumors

    Science.gov (United States)

    Rausch, Thomas; Kahl, Günter; Hilgenberg, Willy

    1984-01-01

    Exogenously added indole-3-acetic acid at a concentration of 100 micromolars stimulates d-glucose uptake (or 3-O-methyl-d-glucose uptake) by 25% in crown gall tumors induced on potato tuber tissue by Agrobacterium tumefaciens strain C 58. The titration of the endogenous IAA with the auxin antagonist 2-naphthaleneacetic acid at 100 micromolars reduces d-glucose uptake by about 80%. The apparent inhibition constant Ki is 21 micromolars. Other auxin antagonists like 1-naphthoxyacetic acid and 2-(p-chlorophenoxy)-2-methylpropionic acid show similar effects. The uptake of the amino acids leucine, methionine, tryptophan, lysine, and aspartic acid is also inhibited by 2-naphthaleneacetic acid to similar degrees. The auxins 1-naphthaleneacetic acid and 2-naphthoxyacetic acid at concentrations between 10 and 100 micromolars inhibit solute uptake only slightly (inhibition less than 20%). The impact of the results on the postulated role of indole-3-acetic acid as a modifier of the electrochemical proton gradient across the plasmalemma in crown gall tumor tissue is discussed. PMID:16663625

  4. Indole-3-acetic acid: A widespread physiological code in interactions of fungi with other organisms.

    Science.gov (United States)

    Fu, Shih-Feng; Wei, Jyuan-Yu; Chen, Hung-Wei; Liu, Yen-Yu; Lu, Hsueh-Yu; Chou, Jui-Yu

    2015-01-01

    Plants as well as microorganisms, including bacteria and fungi, produce indole-3-acetic acid (IAA). IAA is the most common plant hormone of the auxin class and it regulates various aspects of plant growth and development. Thus, research is underway globally to exploit the potential for developing IAA-producing fungi for promoting plant growth and protection for sustainable agriculture. Phylogenetic evidence suggests that IAA biosynthesis evolved independently in bacteria, microalgae, fungi, and plants. Present studies show that IAA regulates the physiological response and gene expression in these microorganisms. The convergent evolution of IAA production leads to the hypothesis that natural selection might have favored IAA as a widespread physiological code in these microorganisms and their interactions. We summarize recent studies of IAA biosynthetic pathways and discuss the role of IAA in fungal ecology.

  5. Amperometric Determination of Indole-3-acetic Acid Based on Platinum Nanowires and Carbon Nanotubes

    Institute of Scientific and Technical Information of China (English)

    Ruo Zhong WANG; Lang Tao XIAO; Ming Hui YANG; Jun Hui DING; Feng Li QU; Guo Li SHEN

    2006-01-01

    Platinum nanowire (PtNW) can be grown by electrodeposition in polycarbonate membrane, with the average diameter of the nanowires about 250 nm. The PtNW and multiwalled carbon nanotubes (CNT) are then dispersed into chitosan (CHIT) solution. The resulting PtNW-CNT-CHIT material brings new capabilities for electrochemical devices by using the synergistic action of the electrocatalytic activity of PtNW and CNT. By dropping the PtNW-CNT-CHIT film onto the glassy carbon (GC) electrode surface, and after evaporationan amperometric sensor for the determination of indole-3-acetic acid (IAA) was developed. The oxidation current of IAA increased significantly at the PtNW-CNT-CHIT film coated GC electrode,in contrast to that at the CNT-CHIT modified GC. The linear response of the sensor is from 50ng/ml to 50 μg/ml with a detection limit of 25 ng/mL.

  6. Isolation of novel indole-3-acetic acid conjugates by immunoaffinity extraction.

    Science.gov (United States)

    Pencík, Ales; Rolcík, Jakub; Novák, Ondrej; Magnus, Volker; Barták, Petr; Buchtík, Roman; Salopek-Sondi, Branka; Strnad, Miroslav

    2009-12-15

    An analytical protocol for the isolation and quantification of indole-3-acetic acid (IAA) and its amino acid conjugates was developed. IAA is an important phytohormone and formation of its conjugates plays a crucial role in regulating IAA levels in plants. The developed protocol combines a highly specific immunoaffinity extraction with a sensitive and selective LC-MS/MS analysis. By using internal standards for each of the studied compounds, IAA and seven amino acid conjugates were analyzed in quantities of fresh plant material as low as 30 mg. In seeds of Helleborus niger, physiological levels of these compounds were found to range from 7.5 nmol g(-1) fresh weight (IAA) to 0.44 pmol g(-1) fresh weight (conjugate with Ala). To our knowledge, the identification of IAA conjugates with Gly, Phe and Val from higher plants is reported here for the first time.

  7. [Enhanced phytoextraction of heavy metal contaminated soil by chelating agents and auxin indole-3-acetic acid].

    Science.gov (United States)

    Zhou, Jian-min; Dang, Zhi; Chen, Neng-chang; Xu, Sheng-guang; Xie, Zhi-yi

    2007-09-01

    The environmental risk of chelating agents such as EDTA application to the heavy metals polluted soils and the stress on plant roots due to the abrupt increase metals concentration limit the wide commercial use of chelate-induced phytoextraction. Chelating agent ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) and auxin indole-3-acetic acid (IAA) were used for enhancing heavy metals uptake from soils by Zea mays L. (corn) in pot experiments. The metals content in plant tissues was quantified using an inductively coupled plasma mass spectrometer (ICP-MS). The results showed that the combination of IAA and EDTA increased the biomass by about 40.0% and the contents of Cu, Zn, Cd and Pb in corn shoots by 27.0%, 26.8%, 27.5% and 32.8% respectively, as compared to those in EDTA treatment. While NTA&IAA treatment increased the biomass by about 29.9% and the contents of Cu, Zn, Cd and Pb in corn shoots by 31.8%, 27.6%, 17.0% and 26.9% respectively, as compared to those in NTA treatment. These results indicated that corn growth was promoted, and the biomass and the accumulation of heavy metals in plant shoots were increased significantly with the addition of IAA, which probably helps to change the cell membrane properties and the biomass distribution, resulting in the alleviation of the phytotoxicity of metals and the chelating agents.

  8. Endohyphal bacterium enhances production of indole-3-acetic acid by a foliar fungal endophyte.

    Science.gov (United States)

    Hoffman, Michele T; Gunatilaka, Malkanthi K; Wijeratne, Kithsiri; Gunatilaka, Leslie; Arnold, A Elizabeth

    2013-01-01

    Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production, providing a new framework in which to explore endophyte-plant interactions.

  9. Binding of ring-substituted indole-3-acetic acids to human serum albumin.

    Science.gov (United States)

    Soskić, Milan; Magnus, Volker

    2007-07-01

    The plant hormone, indole-3-acetic acid (IAA), and its ring-substituted derivatives have recently attracted attention as promising pro-drugs in cancer therapy. Here we present relative binding constants to human serum albumin for IAA and 34 of its derivatives, as obtained using the immobilized protein bound to a support suitable for high-performance liquid chromatography. We also report their octanol-water partition coefficients (logK(ow)) computed from retention data on a C(18) coated silica gel column. A four-parameter QSPR (quantitative structure-property relationships) model, based on physico-chemical properties, is put forward, which accounts for more than 96% of the variations in the binding affinities of these compounds. The model confirms the importance of lipophilicity as a global parameter governing interaction with serum albumin, but also assigns significant roles to parameters specifically related to the molecular topology of ring-substituted IAAs. Bulky substituents at ring-position 6 increase affinity, those at position 2 obstruct binding, while no steric effects were noted at other ring-positions. Electron-withdrawing substituents at position 5 enhance binding, but have no obvious effect at other ring positions.

  10. Modulation of endogenous indole-3-acetic acid biosynthesis in bacteroids within Medicago sativa nodules.

    Science.gov (United States)

    Bianco, C; Senatore, B; Arbucci, S; Pieraccini, G; Defez, R

    2014-07-01

    To evaluate the dose-response effects of endogenous indole-3-acetic acid (IAA) on Medicago plant growth and dry weight production, we increased the synthesis of IAA in both free-living and symbiosis-stage rhizobial bacteroids during Rhizobium-legume symbiosis. For this purpose, site-directed mutagenesis was applied to modify an 85-bp promoter sequence, driving the expression of iaaM and tms2 genes for IAA biosynthesis. A positive correlation was found between the higher expression of IAA biosynthetic genes in free-living bacteria and the increased production of IAA under both free-living and symbiotic conditions. Plants nodulated by RD65 and RD66 strains, synthetizing the highest IAA concentration, showed a significant (up to 73%) increase in the shoot fresh weight and upregulation of nitrogenase gene, nifH, compared to plants nodulated by the wild-type strain. When these plants were analyzed by confocal microscopy, using an anti-IAA antibody, the strongest signal was observed in bacteroids of Medicago sativa RD66 (Ms-RD66) plants, even when they were located in the senescent nodule zone. We show here a simple system to modulate endogenous IAA biosynthesis in bacteria nodulating legumes suitable to investigate which is the maximum level of IAA biosynthesis, resulting in the maximal increase of plant growth.

  11. The use of bacterial indol-3-acetic acid (IAA for reduce of chemical fertilizers doses

    Directory of Open Access Journals (Sweden)

    Đorđević Snežana

    2017-01-01

    Full Text Available The standard technology of seed processing uses mainly chemical products. Recent researches showed that toxic materials from chemical fertilizers can be harmful to humans, animals and the environment. Currently the attention of researches is shifting away from chemical fertlizers and toward alternative that consumers perceive to be natural, Plant Growth Promoting bacteria (PGP. PGP bacteria could be a way to reduce chemical fertilizer doses. This was the reason to test the ability of Bacillus megaterium, Azotobacter chroococcum to produce hormone auxin (IAA. Bacterial strains were identified by PCR amplification and sequencing of the 16S rRNA gene. Indole-3-acetic acid (IAA was detected and quantified by MRM experiment. This study conducted that maize seed inoculation with IAA from species mentioned above showed positive effects. They had statistically significantly higher root and steam height compared to control seedlings. Bacterial strains tested in this study may be recommended as PGP (Plant Growth Promoting bacteria, due to their positive effects and eventually can be used to reduce chemical fertilizers doses.

  12. Synthesis of the [beta]-D-glucosyl ester of [carbonyl-[sup 13]C]-indole-3-acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Jakas, A.; Magnus, V. (Rudjer Boskovic Inst., Zagreb (Croatia)); Horvat, S.; Sandberg, G. (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))

    1993-10-01

    An efficient, operationally simple synthetic approach to 1-O-([carbonyl-[sup 13]C]-indole-3'-ylacetyl)-[beta]-D-glucopyranose is described. The synthesis was carried out by fusing a fully benzylated 1-O-glucosylpseudourea intermediate with [carbonyl-[sup 13]C]-indole-3-acetic acid, followed by hydrogenolytic removal of the protective groups. (Author).

  13. Synthesis and biology of the rigidified glutamate analogue, trans-2-carboxyazetidine-3-acetic acid (t-CAA)

    NARCIS (Netherlands)

    Kozikowski, AP; Liao, Y; Tuckmantel, W; Wang, SM; Pshenichkin, S; Surin, A; Thomsen, C; Wroblewski, JT

    1996-01-01

    Chemical approaches to the (-)- and (+)-trans-2-carboxyazetidine-3-acetic acids (-)-1 and (+)-1, and their homologues (-)-2 and (+)-2, compounds that represent rigidified analogues of glutamate (glu), are reported together with the complete biological characterization of(+)-1 (t-CAA) at the known gl

  14. Biofilm formation and indole-3-acetic acid production by two rhizospheric unicellular cyanobacteria.

    Science.gov (United States)

    Ahmed, Mehboob; Stal, Lucas J; Hasnain, Shahida

    2014-08-01

    Microorganisms that live in the rhizosphere play a pivotal role in the functioning and maintenance of soil ecosystems. The study of rhizospheric cyanobacteria has been hampered by the difficulty to culture and maintain them in the laboratory. The present work investigated the production of the plant hormone indole-3-acetic acid (IAA) and the potential of biofilm formation on the rhizoplane of pea plants by two cyanobacterial strains, isolated from rice rhizosphere. The unicellular cyanobacteria Chroococcidiopsis sp. MMG-5 and Synechocystis sp. MMG-8 that were isolated from a rice rhizosphere, were investigated. Production of IAA by Chroococcidiopsis sp. MMG-5 and Synechocystis sp. MMG-8 was measured under experimental conditions (pH and light). The bioactivity of the cyanobacterial auxin was demonstrated through the alteration of the rooting pattern of Pisum sativum seedlings. The increase in the concentration of L-tryptophan and the time that this amino acid was present in the medium resulted in a significant enhancement of the synthesis of IAA (r > 0.900 at p = 0.01). There was also a significant correlation between the concentration of IAA in the supernatant of the cyanobacteria cultures and the root length and number of the pea seedlings. Observations made by confocal laser scanning microscopy revealed the presence of cyanobacteria on the surface of the roots and also provided evidence for the penetration of the cyanobacteria in the endorhizosphere. We show that the synthesis of IAA by Chroococcidiopsis sp. MMG-5 and Synechocystis sp. MMG-8 occurs under different environmental conditions and that the auxin is important for the development of the seedling roots and for establishing an intimate symbiosis between cyanobacteria and host plants.

  15. Translocation of radiolabeled indole-3-acetic acid and indole-3-acetyl-myo-inositol from kernel to shoot of Zea mays L

    Science.gov (United States)

    Chisnell, J. R.; Bandurski, R. S.

    1988-01-01

    Either 5-[3H]indole-3-acetic acid (IAA) or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm of kernels of dark-grown Zea mays seedlings. The distribution of total radioactivity, radiolabeled indole-3-acetic acid, and radiolabeled ester conjugated indole-3-acetic acid, in the shoots was then determined. Differences were found in the distribution and chemical form of the radiolabeled indole-3-acetic acid in the shoot depending upon whether 5-[3H]indole-3-acetic acid or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm. We demonstrated that indole-3-acetyl-myo-inositol applied to the endosperm provides both free and ester conjugated indole-3-acetic acid to the mesocotyl and coleoptile. Free indole-3-acetic acid applied to the endosperm supplies some of the indole-3-acetic acid in the mesocotyl but essentially no indole-3-acetic acid to the coleoptile or primary leaves. It is concluded that free IAA from the endosperm is not a source of IAA for the coleoptile. Neither radioactive indole-3-acetyl-myo-inositol nor IAA accumulates in the tip of the coleoptile or the mesocotyl node and thus these studies do not explain how the coleoptile tip controls the amount of IAA in the shoot.

  16. Effects of indole-3-acetic acid on Botrytis cinerea isolates obtained from potted plants.

    Science.gov (United States)

    Martínez, J A; Valdés, R; Gómez-Bellot, M J; Bañón, S

    2011-01-01

    We study the growth of different isolates of Botrytis cinerea collected from potted plants which were affected by Botrytis blight in southern Spain during recent years. These isolates, which show widely phenotypic differences when grown in vitro, are differentially affected by growth temperature, gibberellic acid applications and paclobutrazol, an efficient plant growth retardant and fungicide at the same time. In this work, we have evaluated the effect of the auxin indole-3-acetic acid (IAA) dose (0, 1, 10, and 100 mg/plate) on the growth of the collection of B. cinerea isolates obtained from the following potted plants: Cyclamen persicum, Hydrangea macrophylla, Lantona camara, and Lonicera japonica. B. cinerea produces indolacetic acid, but so far the precise biosynthetic pathway and some effects on this fungal species are still unclear, although recent studies have revealed an antifungal activity of IAA on several fungi, including B. cinerea isolated from harvested fruits. Mycelial growth curves and growth rates assessed from difference in colony areas during the both linear and deceleration phase, conidiation (measured as time of appearance), conidia length (microm), and sclerotia production (number/plate) were evaluated in the isolates, which were grown at 26 degrees C on Petri dishes containing potato dextrose agar for up to 35 days. Mycelial growth curves fitted a typical kinetic equation of fungi grown on solid media. B. cinerea isolates showed a high degree of variability in their growth kinetics, depending on the isolate and auxin dose. This plant growth substance delayed mycelial growth during the linear phase in an isolate-dependent manner, thus isolates from C. persicum, H. macrophylla and L. camara were more affected by IAA than L. japonica. On the other hand, 100 mg of IAA was the critical dose to significantly reduce the growth rate in all isolates and to promote brown-striped hyphae development, especially in isolate from C. persicum. 10 and 100 mg

  17. Myo-inositol esters of indole-3-acetic acid are endogenous components of Zea mays L. shoot tissue

    Science.gov (United States)

    Chisnell, J. R.

    1984-01-01

    Indole-3-acetyl-myo-inositol esters have been demonstrated to be endogenous components of etiolated Zea mays shoots tissue. This was accomplished by comparison of the putative compounds with authentic, synthetic esters. The properties compared were liquid and gas-liquid chromatographic retention times and the 70-ev mass spectral fragmentation pattern of the pentaacetyl derivative. The amount of indole-3-acetyl-myo-inositol esters in the shoots was determined to be 74 nanomoles per kilogram fresh weight as measured by isotope dilution, accounting for 19% of the ester indole-3-acetic acid of the shoot. This work is the first characterization of an ester conjugate of indole-3-acetate acid from vegetative shoot tissue using multiple chromatographic properties and mass spectral identification. The kernel and the seedling shoot both contain indole-3-acetyl-myo-inositol esters, and these esters comprise approximately the same percentage of the total ester content of the kernel and of the shoot.

  18. Arabidopsis cytochrome P450s that catalyze the first step of tryptophan-dependent indole-3-acetic acid biosynthesis

    OpenAIRE

    Hull, Anna K.; Vij, Rekha; Celenza, John L.

    2000-01-01

    Plants synthesize numerous secondary metabolites that are used as developmental signals or as defense against pathogens. Tryptophan (Trp)-derived secondary metabolites include camalexin, indole glucosinolates, and indole-3-acetic acid (IAA); however, the steps in their synthesis from Trp or its precursors remain unclear. We have identified two Arabidopsis cytochrome P450s (CYP79B2 and CYP79B3) that can convert Trp to indole-3-acetaldoxime (IAOx), a precursor to IAA and indole glucosinolates.

  19. Anti-tumor Activities of Novel Estrogen Compound 17aα-D-Homo-Ethynylestradiol-3-Acetate

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ze-wei; TANG Wei-sheng; SHEN Xiu; HAN Ying; WANG Xiao-xue; ZHANG Liang-an

    2008-01-01

    Objective:To study the anti-tumor activities of novel estrogen compound 17a α-D-homo-ethvnvlestradiol-3-acetate in vitro and in vivo. Methods:In vitro anti-tumor activity was assayed in adenoma cells A549 and human liver cancer cells Bel-7402 using MTT method,and half-inhibitory concentration (IC50)were observed. In vivo the pulmonary adenoma LA795 cells was selected and the conventional assay method of anti-tumor activity was employed.5,7.5,10 mg/kg of 17a α-D-homo-ethynylestradiol-3-acetate was administered by i.P., and tumor-inhibitory rate, thymus and spleen indexes,bone marrow cells(BMC)were observed. Results:IC50 of 17a α-D-homo-ethynylestradiol-3-acetate in vitro for A549 and Bel-7402 cells were 12.28 μg/ml and 17.79 μg/ml, respectively.In vivo the highest tumor-inhibitory rates for LA795 was 60.0%(P<0.01).The drug had hardly any side-effect in spleen indexes,thymus indexes,and BMC compared with control mice. Nevertheless,compared with the positive control drug cyclophosphamide(CY),thymus and spleen indexes,BMC showed obvious diffefences(P<0.01). Conclusion:17a α-D-homo-ethynylestradiol-3-acetate has obvious anti-tumor activities in vitro and in vivo with low side-effect, thus worth further investigation.

  20. Global Effect of Indole-3-Acetic Acid Biosynthesis on Multiple Virulence Factors of Erwinia chrysanthemi 3937▿

    OpenAIRE

    Yang, Shihui; Zhang, Qiu; Guo, Jianhua; Charkowski, Amy O.; Glick, Bernard R.; Ibekwe, A. Mark; Cooksey, Donald A; Yang, Ching-Hong

    2006-01-01

    Production of the plant hormone indole-3-acetic acid (IAA) is widespread among plant-associated microorganisms. The non-gall-forming phytopathogen Erwinia chrysanthemi 3937 (strain Ech3937) possesses iaaM (ASAP16562) and iaaH (ASAP16563) gene homologues. In this work, the null knockout iaaM mutant strain Ech138 was constructed. The IAA production by Ech138 was reduced in M9 minimal medium supplemented with l-tryptophan. Compared with wild-type Ech3937, Ech138 exhibited reduced ability to prod...

  1. Auxin Biosynthesis: A Simple Two-Step Pathway Converts Tryptophan to Indole-3-Acetic Acid in Plants

    Institute of Scientific and Technical Information of China (English)

    Yunde Zhao

    2012-01-01

    Indole-3-acetic acid (IAA),the main naturally occurring auxin,is essential for almost every aspect of plant growth and development.However,only recently have studies finally established the first complete auxin biosynthesis pathway that converts tryptophan (Trp) to IAA in plants.Trp is first converted to indole-3-pyruvate (IPA) by the TAA family of amino transferases and subsequently IAA is produced from IPA by the YUC family of flavin monooxygenases.The two-step conversion of Trp to IAA is the main auxin biosynthesis pathway that plays an essential role in many developmental processes.

  2. Effect of Gibberellic Acid, Kinetin and Indole 3-Acetic Acid on Seed Germination Performance of Dianthus caryophyllus (Carnation)

    OpenAIRE

    Rajib Roychowdhury; Anuj Mamgain; Sunanda Ray; Jagatpati Tah

    2012-01-01

    The experiment was undertaken with an objective to investigate the effect of various concentrations of plant growth regulators, i.e., Gibberellic acid (GA3), Kinetin and Indole 3-acetic acid (IAA) on seed germination of Dianthus caryophyllus. Dianthus seeds were soaked in different concentrations (0 ppm or control, 10 ppm, 20 ppm, 30 ppm and 40 ppm) of each of GA3, Kinetin and IAA for 24 h at room temperature (25±2oC). Three replicates of each treatment with ten seeds per replicate wer...

  3. Quinazolinone-based rhodanine-3-acetic acids as potent aldose reductase inhibitors: Synthesis, functional evaluation and molecular modeling study.

    Science.gov (United States)

    El-Sayed, Sherihan; Metwally, Kamel; El-Shanawani, Abdalla A; Abdel-Aziz, Lobna M; El-Rashedy, Ahmed A; Soliman, Mahmoud E S; Quattrini, Luca; Coviello, Vito; la Motta, Concettina

    2017-10-15

    A series of quinazolinone-based rhodanine-3-acetic acids was synthesized and tested for in vitro aldose reductase inhibitory activity. All the target compounds displayed nanomolar activity against the target enzyme. Compounds 3a, 3b, and 3e exhibited almost 3-fold higher activity as compared to the only marketed reference drug epalrestat. Structure-activity relationship studies indicated that bulky substituents at the 3-phenyl ring of the quinazolinone moiety are generally not tolerated in the active site of the enzyme. Insertion of a methoxy group on the central benzylidene ring was found to have a variable effect on ALR-2 activity depending on the nature of peripheral quinazolinone ring substituents. Removal of the acetic acid moiety led to inactive or weakly active target compounds. Docking and molecular dynamic simulations of the most active rhodanine-3-acetic acid derivatives were also carried out, to provide the basis for further structure-guided design of novel inhibitors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Simultaneous determination of 2-naphthoxyacetic acid and indole-3-acetic acid by first derivation synchronous fluorescence spectroscopy.

    Science.gov (United States)

    Liu, Xiangxiang; Wan, Yiqun

    2013-07-01

    A simple, rapid, sensitive and selective method for simultaneously determining 2-naphthoxyacetic acid (BNOA) and Indole-3-Acetic Acid (IAA) in mixtures has been developed using derivation synchronous fluorescence spectroscopy based on their synchronous fluorescence. The synchronous fluorescence spectra were obtained with Δλ=100 nm in a pH 8.5 NaH2PO4-NaOH buffer solution, and the detected wavelengths of quantitative analysis were set at 239 nm for BNOA and 293 nm for IAA respectively. The over lapped fluorescence spectra were well separated by the synchronous derivative method. Under optimized conditions, the limits of detection (LOD) were 0.003 μg/mL for BNOA and 0.012 μg/mL for IAA. This method is simple and expeditious, and it has been successfully applied to the determination of 2-naphthoxyacetic acid and indole-3-acetic acid in fruit juice samples with satisfactory results. The samples were only filtrated through a 0.45 μm membrane filter, which was free from the tedious separation procedures. The obtaining recoveries were in the range of 83.88-87.43% for BNOA and 80.76-86.68% for IAA, and the relative standard deviations were all less than 5.0%. Statistical comparison of the results with high performance liquid chromatography Mass Spectrometry (HPLC-MS) method revealed good agreement and proved that there were no significant difference in the accuracy and precision between these two methods.

  5. Simultaneous determination of 2-naphthoxyacetic acid and indole-3-acetic acid by first derivation synchronous fluorescence spectroscopy

    Science.gov (United States)

    Liu, Xiangxiang; Wan, Yiqun

    2013-07-01

    A simple, rapid, sensitive and selective method for simultaneously determining 2-naphthoxyacetic acid (BNOA) and Indole-3-Acetic Acid (IAA) in mixtures has been developed using derivation synchronous fluorescence spectroscopy based on their synchronous fluorescence. The synchronous fluorescence spectra were obtained with Δλ = 100 nm in a pH 8.5 NaH2PO4-NaOH buffer solution, and the detected wavelengths of quantitative analysis were set at 239 nm for BNOA and 293 nm for IAA respectively. The over lapped fluorescence spectra were well separated by the synchronous derivative method. Under optimized conditions, the limits of detection (LOD) were 0.003 μg/mL for BNOA and 0.012 μg/mL for IAA. This method is simple and expeditious, and it has been successfully applied to the determination of 2-naphthoxyacetic acid and indole-3-acetic acid in fruit juice samples with satisfactory results. The samples were only filtrated through a 0.45 μm membrane filter, which was free from the tedious separation procedures. The obtaining recoveries were in the range of 83.88-87.43% for BNOA and 80.76-86.68% for IAA, and the relative standard deviations were all less than 5.0%. Statistical comparison of the results with high performance liquid chromatography Mass Spectrometry (HPLC-MS) method revealed good agreement and proved that there were no significant difference in the accuracy and precision between these two methods.

  6. Regulation of indole-3-acetic acid biosynthesis by branched-chain amino acids in Enterobacter cloacae UW5.

    Science.gov (United States)

    Parsons, Cassandra V; Harris, Danielle M M; Patten, Cheryl L

    2015-09-01

    The soil bacterium Enterobacter cloacae UW5 produces the rhizosphere signaling molecule indole-3-acetic acid (IAA) via the indolepyruvate pathway. Expression of indolepyruvate decarboxylase, a key pathway enzyme encoded by ipdC, is upregulated by the transcription factor TyrR in response to aromatic amino acids. Some members of the TyrR regulon may also be controlled by branched-chain amino acids and here we show that expression from the ipdC promoter and production of IAA are downregulated by valine, leucine and isoleucine. Regulation of the IAA synthesis pathway by both aromatic and branched-chain amino acids suggests a broader role for this pathway in bacterial physiology, beyond plant interactions.

  7. Growth of Brassica juncea under chromium stress: influence of siderophores and indole 3 acetic acid producing rhizosphere bacteria.

    Science.gov (United States)

    Rajkumar, M; Lee, Kui Jae; Lee, Wang Hyu; Banu, J Rajesh

    2005-10-01

    Plant growth promoting rhizobacterial (PGPR) strains A3 and S32 have been shown to promote the growth of Brassica juncea under chromium stress which has been related to the microbial production of siderophores and indole 3 acetic acid (IAA). The aim of the present study is to evaluate the importance of siderophores and IAA producing PGPR on the growth of Brassica juncea under chromium stress. The production of IAA and siderophores were observed in the strains A3 and S32, respectively. Both PGPR strains promote the growth of Brassica juncea under chromium stress. The maximum growth was observed in plants inoculated with siderophores producing strain 32. Both the bacterial inoculum did not influence the uptake of chromium by plants. The present observation showed that PGPR isolates A3 and S32 are capable of protecting the plants against the inhibitory effects of chromium by producing the siderophores and IAA.

  8. Effect of Gibberellic Acid, Kinetin and Indole 3-Acetic Acid on Seed Germination Performance of Dianthus caryophyllus (Carnation

    Directory of Open Access Journals (Sweden)

    Rajib Roychowdhury

    2014-02-01

    Full Text Available The experiment was undertaken with an objective to investigate the effect of various concentrations of plant growth regulators, i.e., Gibberellic acid (GA3, Kinetin and Indole 3-acetic acid (IAA on seed germination of Dianthus caryophyllus. Dianthus seeds were soaked in different concentrations (0 ppm or control, 10 ppm, 20 ppm, 30 ppm and 40 ppm of each of GA3, Kinetin and IAA for 24 h at room temperature (25±2oC. Three replicates of each treatment with ten seeds per replicate were arranged for precise physiological analysis. Significant variation was found in all aspects after analysis of variance (ANOVA of each mean value. After two weeks of seed soaking, it was noted that germination percentages were significantly accelerated by lower concentrations (10 and 20 ppm of used hormones. Amongst the three potential growth regulators, 20 ppm was found most effective because it showed highest germination percentage for GA3 (87.46%, Kinetin (78.92% and IAA (75.35%. A great deal of information relating to seed germination practices shows that these plant growth regulators were efficient in overcoming dormancy leading to rapid seed germination. GA3 was selected as best hormone in this study, which showed highest seed germination (87.46%. These results could be useful in large scale cultivation of Dianthus caryophyllus plants to improve its floricultural impact worldwide.

  9. Transport of the two natural auxins, indole-3-butyric acid and indole-3-acetic acid, in Arabidopsis

    Science.gov (United States)

    Rashotte, Aaron M.; Poupart, Julie; Waddell, Candace S.; Muday, Gloria K.; Brown, C. S. (Principal Investigator)

    2003-01-01

    Polar transport of the natural auxin indole-3-acetic acid (IAA) is important in a number of plant developmental processes. However, few studies have investigated the polar transport of other endogenous auxins, such as indole-3-butyric acid (IBA), in Arabidopsis. This study details the similarities and differences between IBA and IAA transport in several tissues of Arabidopsis. In the inflorescence axis, no significant IBA movement was detected, whereas IAA is transported in a basipetal direction from the meristem tip. In young seedlings, both IBA and IAA were transported only in a basipetal direction in the hypocotyl. In roots, both auxins moved in two distinct polarities and in specific tissues. The kinetics of IBA and IAA transport appear similar, with transport rates of 8 to 10 mm per hour. In addition, IBA transport, like IAA transport, is saturable at high concentrations of auxin, suggesting that IBA transport is protein mediated. Interestingly, IAA efflux inhibitors and mutations in genes encoding putative IAA transport proteins reduce IAA transport but do not alter IBA movement, suggesting that different auxin transport protein complexes are likely to mediate IBA and IAA transport. Finally, the physiological effects of IBA and IAA on hypocotyl elongation under several light conditions were examined and analyzed in the context of the differences in IBA and IAA transport. Together, these results present a detailed picture of IBA transport and provide the basis for a better understanding of the transport of these two endogenous auxins.

  10. Apoptosis of pancreatic cancer BXPC-3 cells induced by indole-3-acetic acid in combination with horseradish peroxidase

    Institute of Scientific and Technical Information of China (English)

    Chen Huang; Lu-Sheng Si; Li-Ying Liu; Tu-Sheng Song; Lei Ni; Ling Yang; Xiao-Yan Hu; Jing-Song Hu; Li-Ping Song; Yu Luo

    2005-01-01

    AIM: To explore the mechanisms underlying the apoptosis of human pancreatic cancer BXPC-3 cells induced by indole-3-acetic acid (TAA) in combination with horseradish peroxidase (HRP).METHODS: BXPC-3 cells derived from human pancreatic cancer were exposed to 40 or 80 μmol/L IAA and 1.2 μg/mL HRP at different times. Then, MTT assay was used to detect the cell proliferation. Flow cytometry was performed to analyze cell cycle. Terminal deoxynucleotidyl transferasemediated dUTP nick end labeling assay was used to detect apoptosis. 2,7-Dichlorofluorescin diacetate uptake was measured by confocal microscopy to determine free radicals. Level of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were measured by biochemical methods.RESULTS: IAA/HRP initiated growth inhibition of BXPC-3 cells in a dose- and time-dependent manner. Flow cytometry revealed that the cells treated for 48 h were arrested at G1/G0. After exposure to 80 μmol/L IAA plus 1.2 μg/mL HRP for 72 h, the apoptosis rate increased to 72.5‰,which was nine times that of control. Content of MDA and activity of SOD increased respectively after treatment compared to control. Meanwhile, IAA/HRP stimulated the formation of free radicals.CONCLUSION: The combination of IAA and HRP can inhibit the growth of human pancreatic cancer BXPC-3 cells in vitro by inducing apoptosis.

  11. Indole-3-acetic acid biosynthesis is deficient in Gluconacetobacter diazotrophicus strains with mutations in cytochrome c biogenesis genes.

    Science.gov (United States)

    Lee, Sunhee; Flores-Encarnación, M; Contreras-Zentella, M; Garcia-Flores, L; Escamilla, J E; Kennedy, Christina

    2004-08-01

    Gluconacetobacter diazotrophicus is an endophyte of sugarcane frequently found in plants grown in agricultural areas where nitrogen fertilizer input is low. Recent results from this laboratory, using mutant strains of G. diazotrophicus unable to fix nitrogen, suggested that there are two beneficial effects of G. diazotrophicus on sugarcane growth: one dependent and one not dependent on nitrogen fixation. A plant growth-promoting substance, such as indole-3-acetic acid (IAA), known to be produced by G. diazotrophicus, could be a nitrogen fixation-independent factor. One strain, MAd10, isolated by screening a library of Tn5 mutants, released only approximately 6% of the amount of IAA excreted by the parent strain in liquid culture. The mutation causing the IAA(-) phenotype was not linked to Tn5. A pLAFR3 cosmid clone that complemented the IAA deficiency was isolated. Sequence analysis of a complementing subclone indicated the presence of genes involved in cytochrome c biogenesis (ccm, for cytochrome c maturation). The G. diazotrophicus ccm operon was sequenced; the individual ccm gene products were 37 to 52% identical to ccm gene products of Escherichia coli and equivalent cyc genes of Bradyrhizobium japonicum. Although several ccm mutant phenotypes have been described in the literature, there are no reports of ccm gene products being involved in IAA production. Spectral analysis, heme-associated peroxidase activities, and respiratory activities of the cell membranes revealed that the ccm genes of G. diazotrophicus are involved in cytochrome c biogenesis.

  12. Dynamics and control of phloem loading of indole-3-acetic acid in seedling cotyledons of Ricinus communis.

    Science.gov (United States)

    Tamas, Imre A; Davies, Peter J

    2016-08-01

    During seed germination, sugars and auxin are produced from stored precursors or conjugates respectively, and transported to the seedling axis. To elucidate the mode of travel of indole-3-acetic acid (IAA) into the phloem, a solution of [(3)H]IAA, together with [(14)C]sucrose, was injected into the endosperm cavity harboring the cotyledons of germinating seedlings of Ricinus communis Phloem exudate from the cut hypocotyl was collected and the radioactivity recorded. Sucrose loading into the phloem was inhibited at higher IAA levels, and the rate of filling of the transient pool(s) was reduced by IAA. IAA was detected within 10min, with the concentration increasing over 30min and reaching a steady-state by 60min. The kinetics indicated that phloem loading of IAA involving both an active, carrier-based, and a passive, diffusion-based component, with IAA traveling along a pathway containing an intermediary pool, possibly the protoplasts of mesophyll cells. Phloem loading of IAA was altered by sucrose, K(+), and a range of non-specific and IAA-specific analogs and inhibitors in a manner that showed that IAA moves into the phloem from the extra cotyledonary solution by multiple pathways, with a carrier-mediated pathway playing a principal role.

  13. Effect of Indole-3-Acetic Acid-Producing Bacteria on Phytoremediation of Soil Contaminated with Phenanthrene and Anthracene by Mungbean

    Directory of Open Access Journals (Sweden)

    Waraporn Chouychai

    2016-07-01

    Full Text Available The use of indole-3-acetic acid (IAA-producing bacteria isolated from non-contaminated weed rhizosphere to enhance plant growth and PAH phytoremediation capacity was investigated. IAA-producing bacterial isolates, designated NSRU1, NSRU2, and NSRU3, were isolated from the rhizosphere of Eleusine indica (Poaceae and Chromolaena odorata (Asteraceae. The isolates were able to produce IAA in nutrient broth. However, when grown in the presence of 100 mg/l of either phenanthrene or anthracene, the amount of IAA produced by each isolate was reduced significantly. Mungbean seedlings were planted in 100 mg/kg phenanthrene- or anthracene-contaminated soil without or with inoculation of ≈106 CFU/g dry soil with one of the bacterial isolates. Inoculation with either NSRU1 or NSRU2 was effective at enhancing shoot length of mungbean in phenanthrene-contaminated soil on day 16. Also, inoculation with isolate NSRU1 led to increased root dry weight of mungbean in phenanthrene-contaminated soil on day 30. Phenanthrene and anthracene degradation on day 16 and 30 in planted and inoculated soil ranged between 92 - 93.8% and 92.2 - 94.1%, respectively, which were not significantly different from planted and uninoculated soil (93.9 and 94.9%. These data showed that IAA-producing bacteria could enhance plant growth, but was unable to increase PAH biodegradation under the conditions tested.

  14. Studies on the growth and indole-3-acetic acid and abscisic acid content of Zea mays seedlings grown in microgravity

    Science.gov (United States)

    Schulze, A.; Jensen, P. J.; Desrosiers, M.; Buta, J. G.; Bandurski, R. S.

    1992-01-01

    Measurements were made of the fresh weight, dry weight, dry weight-fresh weight ratio, free and conjugated indole-3-acetic acid, and free and conjugated abscisic acid in seedlings of Zea mays grown in darkness in microgravity and on earth. Imbibition of the dry kernels was 17 h prior to launch. Growth was for 5 d at ambient orbiter temperature and at a chronic accelerational force of the order of 3 x 10(-5) times earth gravity. Weights and hormone content of the microgravity seedlings were, with minor exceptions, not statistically different from seedlings grown in normal gravity. The tissues of the shuttle-grown plants appeared normal and the seedlings differed only in the lack of orientation of roots and shoots. These findings, based upon 5 d of growth in microgravity, cannot be extrapolated to growth in microgravity for weeks, months, and years, as might occur on a space station. Nonetheless, it is encouraging, for prospects of bioregeneration of the atmosphere and food production in a space station, that no pronounced differences in the parameters measured were apparent during the 5 d of plant seedling growth in microgravity.

  15. Effect of Gibberellic Acid, Kinetin and Indole 3-Acetic Acid on Seed Germination Performance of Dianthus caryophyllus (Carnation

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    Rajib Roychowdhury

    2012-09-01

    Full Text Available The experiment was undertaken with an objective to investigate the effect of various concentrations of plant growth regulators, i.e., Gibberellic acid (GA3, Kinetin and Indole 3-acetic acid (IAA on seed germination of Dianthus caryophyllus. Dianthus seeds were soaked in different concentrations (0 ppm or control, 10 ppm, 20 ppm, 30 ppm and 40 ppm of each of GA3, Kinetin and IAA for 24 h at room temperature (25±2oC. Three replicates of each treatment with ten seeds per replicate were arranged for precise physiological analysis. Significant variation was found in all aspects after analysis of variance (ANOVA of each mean value. After two weeks of seed soaking, it was noted that germination percentages were significantly accelerated by lower concentrations (10 and 20 ppm of used hormones. Amongst the three potential growth regulators, 20 ppm was found most effective because it showed highest germination percentage for GA3 (87.46%, Kinetin (78.92% and IAA (75.35%. A great deal of information relating to seed germination practices shows that these plant growth regulators were efficient in overcoming dormancy leading to rapid seed germination. GA3 was selected as best hormone in this study, which showed highest seed germination (87.46%. These results could be useful in large scale cultivation of Dianthus caryophyllus plants to improve its floricultural impact worldwide.

  16. Effect of Gibberellic Acid, Kinetin and Indole 3-Acetic Acid on Seed Germination Performance of Dianthus caryophyllus (Carnation

    Directory of Open Access Journals (Sweden)

    Rajib Roychowdhury

    2012-10-01

    Full Text Available The experiment was undertaken with an objective to investigate the effect of various concentrations of plant growth regulators, i.e., Gibberellic acid (GA3, Kinetin and Indole 3-acetic acid (IAA on seed germination of Dianthus caryophyllus. Dianthus seeds were soaked in different concentrations (0 ppm or control, 10 ppm, 20 ppm, 30 ppm and 40 ppm of each of GA3, Kinetin and IAA for 24 h at room temperature (25±2oC. Three replicates of each treatment with ten seeds per replicate were arranged for precise physiological analysis. Significant variation was found in all aspects after analysis of variance (ANOVA of each mean value. After two weeks of seed soaking, it was noted that germination percentages were significantly accelerated by lower concentrations (10 and 20 ppm of used hormones. Amongst the three potential growth regulators, 20 ppm was found most effective because it showed highest germination percentage for GA3 (87.46%, Kinetin (78.92% and IAA (75.35%. A great deal of information relating to seed germination practices shows that these plant growth regulators were efficient in overcoming dormancy leading to rapid seed germination. GA3 was selected as best hormone in this study, which showed highest seed germination (87.46%. These results could be useful in large scale cultivation of Dianthus caryophyllus plants to improve its floricultural impact worldwide.

  17. Surface colonization by Azospirillum brasilense SM in the indole-3-acetic acid dependent growth improvement of sorghum.

    Science.gov (United States)

    Kochar, Mandira; Srivastava, Sheela

    2012-04-01

    The key to improving plant productivity is successful bacterial-plant interaction in the rhizosphere that can be maintained in the environment. The results presented here confirm Azospirillum brasilense strain SM as a competent plant growth promoting bacterium over mid- and long-term associations with sorghum. This study establishes that plant growth can be directly correlated with the associated bacterium's indole-3-acetic acid (IAA) production capability as IAA over-expressing variants, SMp30 and SMΔi3-6 fared better than the wild type strain. The auxin antagonist, p-chlorophenoxy isobutyric acid confirmed the role of bacterial IAA in plant growth promotion and verified the presence of larger amount of IAA available to the seeds on inoculation with IAA over-expressing mutants. Microscopic analysis identified the bacterial association at root tips, root-shoot junction and elongation zone and their surface colonizing nature. Scanning electron microscopy identified larger number of root hairs and extensive exopolysaccharide covering in comparison to untreated ones. In addition, vibroid-shaped Azospirilla attached by means of fibrillar material were dispersed along the elongation zone. The notable difference with IAA over-expressing variants was enhanced number of root hairs. Thus, the variant strains may be more efficient surface colonizers of the sorghum root and used as superior bio-inoculants for improving plant productivity.

  18. Dynamics and control of phloem loading of indole-3-acetic acid in seedling cotyledons of Ricinus communis

    Science.gov (United States)

    Tamas, Imre A.; Davies, Peter J.

    2016-01-01

    During seed germination, sugars and auxin are produced from stored precursors or conjugates respectively, and transported to the seedling axis. To elucidate the mode of travel of indole-3-acetic acid (IAA) into the phloem, a solution of [3H]IAA, together with [14C]sucrose, was injected into the endosperm cavity harboring the cotyledons of germinating seedlings of Ricinus communis. Phloem exudate from the cut hypocotyl was collected and the radioactivity recorded. Sucrose loading into the phloem was inhibited at higher IAA levels, and the rate of filling of the transient pool(s) was reduced by IAA. IAA was detected within 10min, with the concentration increasing over 30min and reaching a steady-state by 60min. The kinetics indicated that phloem loading of IAA involving both an active, carrier-based, and a passive, diffusion-based component, with IAA traveling along a pathway containing an intermediary pool, possibly the protoplasts of mesophyll cells. Phloem loading of IAA was altered by sucrose, K+, and a range of non-specific and IAA-specific analogs and inhibitors in a manner that showed that IAA moves into the phloem from the extra cotyledonary solution by multiple pathways, with a carrier-mediated pathway playing a principal role. PMID:27371947

  19. Indole-3-acetic acid-producing yeasts in the phyllosphere of the carnivorous plant Drosera indica L.

    Science.gov (United States)

    Sun, Pei-Feng; Fang, Wei-Ta; Shin, Li-Ying; Wei, Jyuan-Yu; Fu, Shih-Feng; Chou, Jui-Yu

    2014-01-01

    Yeasts are widely distributed in nature and exist in association with other microorganisms as normal inhabitants of soil, vegetation, and aqueous environments. In this study, 12 yeast strains were enriched and isolated from leaf samples of the carnivorous plant Drosera indica L., which is currently threatened because of restricted habitats and use in herbal industries. According to similarities in large subunit and small subunit ribosomal RNA gene sequences, we identified 2 yeast species in 2 genera of the phylum Ascomycota, and 5 yeast species in 5 genera of the phylum Basidiomycota. All of the isolated yeasts produced indole-3-acetic acid (IAA) when cultivated in YPD broth supplemented with 0.1% L-tryptophan. Growth conditions, such as the pH and temperature of the medium, influenced yeast IAA production. Our results also suggested the existence of a tryptophan-independent IAA biosynthetic pathway. We evaluated the effects of various concentrations of exogenous IAA on yeast growth and observed that IAA produced by wild yeasts modifies auxin-inducible gene expression in Arabidopsis. Our data suggest that yeasts can promote plant growth and support ongoing prospecting of yeast strains for inclusion into biofertilizer for sustainable agriculture.

  20. Indole-3-acetic acid-producing yeasts in the phyllosphere of the carnivorous plant Drosera indica L.

    Directory of Open Access Journals (Sweden)

    Pei-Feng Sun

    Full Text Available Yeasts are widely distributed in nature and exist in association with other microorganisms as normal inhabitants of soil, vegetation, and aqueous environments. In this study, 12 yeast strains were enriched and isolated from leaf samples of the carnivorous plant Drosera indica L., which is currently threatened because of restricted habitats and use in herbal industries. According to similarities in large subunit and small subunit ribosomal RNA gene sequences, we identified 2 yeast species in 2 genera of the phylum Ascomycota, and 5 yeast species in 5 genera of the phylum Basidiomycota. All of the isolated yeasts produced indole-3-acetic acid (IAA when cultivated in YPD broth supplemented with 0.1% L-tryptophan. Growth conditions, such as the pH and temperature of the medium, influenced yeast IAA production. Our results also suggested the existence of a tryptophan-independent IAA biosynthetic pathway. We evaluated the effects of various concentrations of exogenous IAA on yeast growth and observed that IAA produced by wild yeasts modifies auxin-inducible gene expression in Arabidopsis. Our data suggest that yeasts can promote plant growth and support ongoing prospecting of yeast strains for inclusion into biofertilizer for sustainable agriculture.

  1. Indole-3-Acetic Acid-Producing Yeasts in the Phyllosphere of the Carnivorous Plant Drosera indica L

    Science.gov (United States)

    Shin, Li-Ying; Wei, Jyuan-Yu; Fu, Shih-Feng; Chou, Jui-Yu

    2014-01-01

    Yeasts are widely distributed in nature and exist in association with other microorganisms as normal inhabitants of soil, vegetation, and aqueous environments. In this study, 12 yeast strains were enriched and isolated from leaf samples of the carnivorous plant Drosera indica L., which is currently threatened because of restricted habitats and use in herbal industries. According to similarities in large subunit and small subunit ribosomal RNA gene sequences, we identified 2 yeast species in 2 genera of the phylum Ascomycota, and 5 yeast species in 5 genera of the phylum Basidiomycota. All of the isolated yeasts produced indole-3-acetic acid (IAA) when cultivated in YPD broth supplemented with 0.1% L-tryptophan. Growth conditions, such as the pH and temperature of the medium, influenced yeast IAA production. Our results also suggested the existence of a tryptophan-independent IAA biosynthetic pathway. We evaluated the effects of various concentrations of exogenous IAA on yeast growth and observed that IAA produced by wild yeasts modifies auxin-inducible gene expression in Arabidopsis. Our data suggest that yeasts can promote plant growth and support ongoing prospecting of yeast strains for inclusion into biofertilizer for sustainable agriculture. PMID:25464336

  2. Immunolocalization of endogenous indole-3-acetic acid and abscisic acid in the shoot internodes of Fargesia yunnanensis bamboo during development

    Science.gov (United States)

    Shuguang Wang; Yongpeng Ma; Chengbin Wan; Chungyun Hse; Todd F. Shupe; Yujun Wang; Changming. Wang

    2016-01-01

    The Bambusoideae subfamily includes the fastest-growing plants worldwide, as a consequence of fast internode elongation. However, few studies have evaluated the temporal and spatial distribution of endogenous hormones during internode elongation. In this paper, endogenous indole-3-acetic acid (IAA) and abscisic acid (ABA) were detected in different developmental...

  3. Involvement of indole-3-acetic acid produced by Azospirillum brasilense in accumulating intracellular ammonium in Chlorella vulgaris.

    Science.gov (United States)

    Meza, Beatriz; de-Bashan, Luz E; Bashan, Yoav

    2015-01-01

    Accumulation of intracellular ammonium and activities of the enzymes glutamine synthetase (GS) and glutamate dehydrogenase (GDH) were measured when the microalgae Chlorella vulgaris was immobilized in alginate with either of two wild type strains of Azospirillum brasilense or their corresponding indole-3-acetic acid (IAA)-attenuated mutants. After 48 h of immobilization, both wild types induced higher levels of intracellular ammonium in the microalgae than their respective mutants; the more IAA produced, the higher the intracellular ammonium accumulated. Accumulation of intracellular ammonium in the cells of C. vulgaris followed application of four levels of exogenous IAA reported for A. brasilense and its IAA-attenuated mutants, which had a similar pattern for the first 24 h. This effect was transient and disappeared after 48 h of incubation. Immobilization of C. vulgaris with any bacteria strain induced higher GS activity. The bacterial strains also had GS activity, comparable to the activity detected in C. vulgaris, but weaker than when immobilized with the bacteria. When net activity was calculated, the wild type always induced higher GS activity than IAA-attenuated mutants. GDH activity in most microalgae/bacteria interactions resembled GS activity. When complementing IAA-attenuated mutants with exogenous IAA, GS activity in co-immobilized cultures matched those of the wild type A. brasilense immobilized with the microalga. Similarity occurred when the net GS activity was measured, and was higher with greater quantities of exogenous IAA. It is proposed that IAA produced by A. brasilense is involved in ammonium uptake and later assimilation by C. vulgaris.

  4. Endophytic actinomycetes from spontaneous plants of Algerian Sahara: indole-3-acetic acid production and tomato plants growth promoting activity.

    Science.gov (United States)

    Goudjal, Yacine; Toumatia, Omrane; Sabaou, Nasserdine; Barakate, Mustapha; Mathieu, Florence; Zitouni, Abdelghani

    2013-10-01

    Twenty-seven endophytic actinomycete strains were isolated from five spontaneous plants well adapted to the poor sandy soil and arid climatic conditions of the Algerian Sahara. Morphological and chemotaxonomical analysis indicated that twenty-two isolates belonged to the Streptomyces genus and the remaining five were non-Streptomyces. All endophytic strains were screened for their ability to produce indole-3-acetic acid (IAA) in vitro on a chemically defined medium. Eighteen strains were able to produce IAA and the maximum production occurred with the Streptomyces sp. PT2 strain. The IAA produced was further extracted, partially purified and confirmed by thin layer chromatography (TLC) analysis. The 16S rDNA sequence analysis and phylogenetic studies indicated that strain PT2 was closely related to Streptomyces enissocaecilis NRRL B 16365(T), Streptomyces rochei NBRC 12908(T) and Streptomyces plicatus NBRC 13071(T), with 99.52 % similarity. The production of IAA was affected by cultural conditions such as temperature, pH, incubation period and L-tryptophan concentration. The highest level of IAA production (127 μg/ml) was obtained by cultivating the Streptomyces sp. PT2 strain in yeast extract-tryptone broth supplemented with 5 mg L-tryptophan/ml at pH 7 and incubated on a rotary shaker (200 rpm) at 30 °C for 5 days. Twenty-four-hour treatment of tomato cv. Marmande seeds with the supernatant culture of Streptomyces sp. PT2 that contained the crude IAA showed the maximum effect in promoting seed germination and root elongation.

  5. Medicago truncatula improves salt tolerance when nodulated by an indole-3-acetic acid-overproducing Sinorhizobium meliloti strain.

    Science.gov (United States)

    Bianco, Carmen; Defez, Roberto

    2009-01-01

    The abiotic stress resistance of wild-type Sinorhizobium meliloti 1021 was compared with that of RD64, a derivative of the 1021 strain harbouring an additional pathway for the synthesis of indole-3-acetic acid (IAA), expressed in both free-living bacteria and bacteroids. It is shown here that the IAA-overproducing RD64 strain accumulated a higher level of trehalose as its endogenous osmolyte and showed an increased tolerance to several stress conditions (55 degrees C, 4 degrees C, UV-irradiation, 0.5 M NaCl, and pH 3). Medicago truncatula plants nodulated by RD64 (Mt-RD64) showed re-modulation of phytohormones, with a higher IAA content in nodules and roots and a decreased IAA level in shoots as compared with plants nodulated by the wild-type strain 1021 (Mt-1021). The response of nodulated M. truncatula plants to salt stress, when 0.3 M NaCl was applied, was analysed. For Mt-RD64 plants higher internal proline contents, almost unchanged hydrogen peroxide levels, and enhanced activity of antioxidant enzymes (superoxide dismutase, total peroxidase, glutathione reductase, and ascorbate peroxidase) were found compared with Mt-1021 plants. These results were positively correlated with reduced symptoms of senescence, lower expression of ethylene signalling genes, lower reduction of shoot dry weight, and better nitrogen-fixing capacity observed for these plants. Upon re-watering, after 0.3 M NaCl treatment, Mt-1021 plants almost die whereas Mt-RD64 plants showed visual signs of recovery. Finally, the shoot dry weight of Mt-RD64 plants treated with 0.15 M NaCl was not statistically different from that of Mt-1021 plants grown under non-stressed conditions.

  6. Tryptophan, thiamine and indole-3-acetic acid exchange between Chlorella sorokiniana and the plant growth-promoting bacterium Azospirillum brasilense.

    Science.gov (United States)

    Palacios, Oskar A; Gomez-Anduro, Gracia; Bashan, Yoav; de-Bashan, Luz E

    2016-06-01

    During synthetic mutualistic interactions between the microalga Chlorella sorokiniana and the plant growth-promoting bacterium (PGPB) Azospirillum brasilense, mutual exchange of resources involved in producing and releasing the phytohormone indole-3-acetic acid (IAA) by the bacterium, using tryptophan and thiamine released by the microalga, were measured. Although increased activities of tryptophan synthase in C. sorokiniana and indole pyruvate decarboxylase (IPDC) in A. brasilense were observed, we could not detect tryptophan or IAA in the culture medium when both organisms were co-immobilized. This indicates that no extra tryptophan or IAA is produced, apart from the quantities required to sustain the interaction. Over-expression of the ipdC gene occurs at different incubation times: after 48 h, when A. brasilense was immobilized alone and grown in exudates of C. sorokiniana and at 96 h, when A. brasilense was co-immobilized with the microalga. When A. brasilense was cultured in exudates of C. sorokiniana, increased expression of the ipdC gene, corresponding increase in activity of IPDC encoded by the ipdC gene, and increase in IAA production were measured during the first 48 h of incubation. IAA production and release by A. brasilense was found only when tryptophan and thiamine were present in a synthetic growth medium (SGM). The absence of thiamine in SGM yielded no detectable IAA. In summary, this study demonstrates that C. sorokiniana can exude sufficient tryptophan and thiamine to allow IAA production by a PGPB during their interaction. Thiamine is essential for IAA production by A. brasilense and these three metabolites are part of a communication between the two microorganisms.

  7. Enterococcus faecium LKE12 Cell-Free Extract Accelerates Host Plant Growth via Gibberellin and Indole-3-Acetic Acid Secretion.

    Science.gov (United States)

    Lee, Ko-Eun; Radhakrishnan, Ramalingam; Kang, Sang-Mo; You, Young-Hyun; Joo, Gil-Jae; Lee, In-Jung; Ko, Jae-Hwan; Kim, Jin-Ho

    2015-09-01

    The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA1, GA3, GA7, GA8, GA9, GA12, GA19, GA20, GA24, and GA53), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.

  8. Occurrence of indole-3-acetic Acid-producing bacteria on pear trees and their association with fruit russet.

    Science.gov (United States)

    Lindow, S E; Desurmont, C; Elkins, R; McGourty, G; Clark, E; Brandl, M T

    1998-11-01

    ABSTRACT A relatively high percentage of epiphytic bacteria on pear leaf and fruit surfaces had the ability to produce indole-3-acetic acid (IAA) in culture media supplemented with tryptophan. While over 50% of the strains produced at least small amounts of IAA in culture, about 25% of the strains exhibited high IAA production as evidenced by both colorimetric and high-performance liquid chromatography analysis of culture supernatants. A majority of the strains that produced high amounts of IAA were identified as Erwinia herbicola (Pantoea agglomerans), while some strains of Pseudomonas syringae, Pseudomonas viridiflava, Pseudomonas fluorescens, Pseudomonas putida, and Rahnella aquaticus that produced high amounts of IAA also were found on pear. Fruit russeting was significantly increased in 39 out of 46 trials over an 8-year period in which IAA-producing bacteria were applied to trees compared with control trees. A linear relationship was observed between fruit russet severity and the logarithm of the population size of different IAA-producing bacteria on trees in the 30 days after inoculation, when normalized for the amount of IAA produced by each strain in culture. On average, the severity of fruit russet was only about 77% that on control trees when trees were treated at the time of bloom with Pseudomonas fluorescens strain A506, which does not produce IAA. Both total bacterial populations on pear in the 30-day period following full bloom and fruit russet severity varied greatly from year to year and in different commercial orchards over a 10-year period. There was a strong linear correlation between the logarithm of total bacterial population sizes and fruit russet severity.

  9. Identification of genes involved in indole-3-acetic acid biosynthesis by Gluconacetobacter diazotrophicus PAL5 strain using transposon mutagenesis

    Directory of Open Access Journals (Sweden)

    ELISETE PAINS RODRIGUES

    2016-10-01

    Full Text Available Gluconacetobacter diazotrophicus is a beneficial nitrogen-fixing endophyte found in association with sugarcane plants and other important crops. Beneficial effects of G. diazotrophicus on sugarcane growth and productivity have been attributed to biological nitrogen fixation process and production of phytohormones especially indole-3-acetic acid (IAA; however, information about the biosynthesis and function of IAA in G. diazotrophicus is still scarce. Therefore, the aim of this work was to identify genes and pathways involved in IAA biosynthesis in this bacterium. In our study, the screening of two independent Tn5 mutant libraries of PAL5T strain using the Salkowski colorimetric assay revealed two mutants (Gdiaa34 and Gdiaa01, which exhibited 95% less indolic compounds that the parental strain when grown in LGIP medium supplemented with L-tryptophan. HPLC chromatograms of the wild-type strain revealed the presence of IAA and of the biosynthetic intermediates indole-3-pyruvic acid (IPyA and indole-3-lactate (ILA. In contrast, the HPLC profiles of both mutants showed no IAA but only a large peak of non-metabolized tryptophan and low levels of IPyA and ILA were detected. Molecular characterization revealed that Gdiaa01 and Gdiaa34 mutants had unique Tn5 insertions at different sites within the GDI2456 open read frame, which is predicted to encode a L-amino acid oxidase (LAAO. GDI2456 (lao gene forms a cluster with GDI2455 and GDI2454 ORFs, which are predicted to encode a cytochrome C and an RidA protein, respectively. RT-qPCR showed that transcript levels of lao, cccA and ridA genes were reduced in the Gdiaa01 as compared to PAL5T. In addition, rice plants inoculated with Gdiaa01 showed significantly smaller root development (length, surface area, number of forks and tips than those plants inoculated with PAL5T. In conclusion, our study demonstrated that G. diazotrophicus PAL5T produces IAA via the IPyA pathway in cultures supplemented with

  10. Identification of Genes Involved in Indole-3-Acetic Acid Biosynthesis by Gluconacetobacter diazotrophicus PAL5 Strain Using Transposon Mutagenesis

    Science.gov (United States)

    Rodrigues, Elisete P.; Soares, Cleiton de Paula; Galvão, Patrícia G.; Imada, Eddie L.; Simões-Araújo, Jean L.; Rouws, Luc F. M.; de Oliveira, André L. M.; Vidal, Márcia S.; Baldani, José I.

    2016-01-01

    Gluconacetobacter diazotrophicus is a beneficial nitrogen-fixing endophyte found in association with sugarcane plants and other important crops. Beneficial effects of G. diazotrophicus on sugarcane growth and productivity have been attributed to biological nitrogen fixation process and production of phytohormones especially indole-3-acetic acid (IAA); however, information about the biosynthesis and function of IAA in G. diazotrophicus is still scarce. Therefore, the aim of this work was to identify genes and pathways involved in IAA biosynthesis in this bacterium. In our study, the screening of two independent Tn5 mutant libraries of PAL5T strain using the Salkowski colorimetric assay revealed two mutants (Gdiaa34 and Gdiaa01), which exhibited 95% less indolic compounds than the parental strain when grown in LGIP medium supplemented with L-tryptophan. HPLC chromatograms of the wild-type strain revealed the presence of IAA and of the biosynthetic intermediates indole-3-pyruvic acid (IPyA) and indole-3-lactate (ILA). In contrast, the HPLC profiles of both mutants showed no IAA but only a large peak of non-metabolized tryptophan and low levels of IPyA and ILA were detected. Molecular characterization revealed that Gdiaa01 and Gdiaa34 mutants had unique Tn5 insertions at different sites within the GDI2456 open read frame, which is predicted to encode a L-amino acid oxidase (LAAO). GDI2456 (lao gene) forms a cluster with GDI2455 and GDI2454 ORFs, which are predicted to encode a cytochrome C and an RidA protein, respectively. RT-qPCR showed that transcript levels of lao. cccA, and ridA genes were reduced in the Gdiaa01 as compared to PAL5T. In addition, rice plants inoculated with Gdiaa01 showed significantly smaller root development (length, surface area, number of forks and tips) than those plants inoculated with PAL5T. In conclusion, our study demonstrated that G. diazotrophicus PAL5T produces IAA via the IPyA pathway in cultures supplemented with tryptophan and

  11. Indole-3-acetic acid in plant-pathogen interactions: a key molecule for in planta bacterial virulence and fitness.

    Science.gov (United States)

    Cerboneschi, Matteo; Decorosi, Francesca; Biancalani, Carola; Ortenzi, Maria Vittoria; Macconi, Sofia; Giovannetti, Luciana; Viti, Carlo; Campanella, Beatrice; Onor, Massimo; Bramanti, Emilia; Tegli, Stefania

    The plant pathogenic bacterium Pseudomonas savastanoi, the causal agent of olive and oleander knot disease, uses the so-called "indole-3-acetamide pathway" to convert tryptophan to indole-3-acetic acid (IAA) via a two-step pathway catalyzed by enzymes encoded by the genes in the iaaM/iaaH operon. Moreover, pathovar nerii of P. savastanoi is able to conjugate IAA to lysine to generate the less biologically active compound IAA-Lys via the enzyme IAA-lysine synthase encoded by the iaaL gene. Interestingly, iaaL is now known to be widespread in many Pseudomonas syringae pathovars, even in the absence of the iaaM and iaaH genes for IAA biosynthesis. Here, two knockout mutants, ΔiaaL and ΔiaaM, of strain Psn23 of P. savastanoi pv. nerii were produced. Pathogenicity tests using the host plant Nerium oleander showed that ΔiaaL and ΔiaaM were hypervirulent and hypovirulent, respectively and these features appeared to be related to their differential production of free IAA. Using the Phenotype Microarray approach, the chemical sensitivity of these mutants was shown to be comparable to that of wild-type Psn23. The main exception was 8 hydroxyquinoline, a toxic compound that is naturally present in plant exudates and is used as a biocide, which severely impaired the growth of ΔiaaL and ΔiaaM, as well as growth of the non-pathogenic mutant ΔhrpA, which lacks a functional Type Three Secretion System (TTSS). According to bioinformatics analysis of the Psn23 genome, a gene encoding a putative Multidrug and Toxic compound Extrusion (MATE) transporter, was found upstream of iaaL. Similarly to iaaL and iaaM, its expression appeared to be TTSS-dependent. Moreover, auxin-responsive elements were identified for the first time in the modular promoters of both the iaaL gene and the iaaM/iaaH operon of P. savastanoi, suggesting their IAA-inducible transcription. Gene expression analysis of several genes related to TTSS, IAA metabolism and drug resistance confirmed the presence of a

  12. Enzymatic synthesis of 5-/sup 3/H-indole-3-acetic acid and 5-/sup 3/H-indole-3-acetyl-myo-inositol from 5-/sup 3/H-L-trytophan

    Energy Technology Data Exchange (ETDEWEB)

    Michalczuk, L.; Chisnell, J.R. (Michigan State Univ., East Lansing (USA). Dept. of Botany and Plant Pathology)

    1982-01-01

    Labeled 1-tryptophan is converted to indole-3-acetamide and then to indole-3-acetic acid by enzymes from Pseudomonas savastanoi. Labeled indole-3-acetic acid can be converted to indole-3-acetyl-1-O-..beta..-D-glucose and to indole-3-acetyl-myo-inositol by enzymes from kernels of Zea mays sweet corn.

  13. Molecular characterization of two cloned nitrilases from Arabidopsis thaliana: key enzymes in biosynthesis of the plant hormone indole-3-acetic acid.

    Science.gov (United States)

    Bartling, D; Seedorf, M; Schmidt, R C; Weiler, E W

    1994-06-21

    As in maize [Wright, A.D., Sampson, M. B., Neuffer, M. G., Michalczuk, L., Slovin, J. P. & Cohen, J. D. (1991) Science 254, 998-1000], the major auxin of higher plants, indole-3-acetic acid, is synthesized mainly via a nontryptophan pathway in Arabidopsis thaliana [Normanly, J., Cohen, J. D. & Fink, G. R. (1993) Proc. Natl. Acad. Sci. USA 90, 10355-10359]. In the latter species, the hormone may be accessible from the glucosinolate glucobrassicin (indole-3-methyl glucosinolate) and from L-tryptophan via indoleacetaldoxime under special circumstances. In each case, indole-3-acetonitrile is the immediate precursor, which is converted into indole-3-acetic acid through the action of nitrilase (nitrile aminohydrolase, EC 3.5.5.1). The genome of A. thaliana contains two nitrilase genes. Nitrilase I had been cloned earlier in our laboratory. The cDNA for nitrilase II (PM255) was cloned and encodes an enzyme that converts indole-3-acetonitrile to indole-3-acetic acid, the plant hormone. We show that the intracellular location as well as the expression pattern of the two A. thaliana nitrilases are distinctly different. Nitrilase I is soluble and is expressed throughout development, but at a very low level during the fruiting stage, while nitrilase II is tightly associated with the plasma membrane, is barely detectable in young rosettes, but is strongly expressed during bolting, flowering, and especially fruit development. The results indicate that more than one pathway of indole-3-acetic acid biosynthesis via indole-3-acetonitrile exists in A. thaliana and that these pathways are differentially regulated throughout plant development.

  14. Study of the mechanism on the apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase

    Institute of Scientific and Technical Information of China (English)

    宋土生; 杨玲; 黄辰; 刘利英; 倪磊; 王爱英; 罗禹

    2007-01-01

    Indole-3-acetic acid(IAA)is an i mportant typeof the plant growth hor mone found in higherplants,and participate inthe regulation of plant celldivision,elongation and differentiation.It is pres-ent in human urine,blood plas ma and central nerv-ous system.IAAis well tolerated in human and isnot oxidized by mammalian peroxidase.Recent re-searches suggest that the combination of IAA andhorseradish peroxidase(HRP)is cytotoxic to mam-malian cells,and could be used as a novel cancertherapy[1-3],while neither IAAn...

  15. Concurrent profiling of indole-3-acetic acid, abscisic acid, and cytokinins and structurally related purines by high-performance-liquid-chromatography tandem electrospray mass spectrometry

    Directory of Open Access Journals (Sweden)

    Farrow Scott C

    2012-10-01

    Full Text Available Abstract Background Cytokinins (CKs are a group of plant growth regulators that are involved in several plant developmental processes. Despite the breadth of knowledge surrounding CKs and their diverse functions, much remains to be discovered about the full potential of CKs, including their relationship with the purine salvage pathway, and other phytohormones. The most widely used approach to query unknown facets of CK biology utilized functional genomics coupled with CK metabolite assays and screening of CK associated phenotypes. There are numerous different types of assays for determining CK quantity, however, none of these methods screen for the compendium of metabolites that are necessary for elucidating all roles, including purine salvage pathway enzymes in CK metabolism, and CK cross-talk with other phytohormones. Furthermore, all published analytical methods have drawbacks ranging from the required use of radiolabelled compounds, or hazardous derivatization reagents, poor sensitivity, lack of resolution between CK isomers and lengthy run times. Results In this paper, a method is described for the concurrent extraction, purification and analysis of several CKs (freebases, ribosides, glucosides, nucleotides, purines (adenosine monophosphate, inosine, adenosine, and adenine, indole-3-acetic acid, and abscisic acid from hundred-milligram (mg quantities of Arabidopsis thaliana leaf tissue. This method utilizes conventional Bieleski solvents extraction, solid phase purification, and is unique because of its diverse range of detectable analytes, and implementation of a conventional HPLC system with a fused core column that enables good sensitivity without the requirement of a UHPLC system. Using this method we were able to resolve CKs about twice as fast as our previous method. Similarly, analysis of adenosine, indole-3-acetic acid, and abscisic acid, was comparatively rapid. A further enhancement of the method was the utilization of a QTRAP

  16. Ethylene-enhanced catabolism of ( sup 14 C)indole-3-acetic acid to indole-3-carboxylic acid in citrus leaf tissues. [Citrus sinensis

    Energy Technology Data Exchange (ETDEWEB)

    Sagee, O.; Riov, J.; Goren, J. (Hebrew Univ. of Jerusalem, Rehovot (Israel))

    1990-01-01

    Exogenous ({sup 14}C)indole-3-acetic acid (IAA) is conjugated in citrus (Citrus sinensis) leaf tissues to one major substance which has been identified as indole-3-acetylaspartic acid (IAAsp). Ethylene pretreatment enhanced the catabolism of ({sup 14}C)IAA to indole-3-carboxylic acid (ICA), which accumulated as glucose esters (ICGlu). Increased formation of ICGlu by ethylene was accompanied by a concomitant decrease in IAAsp formation. IAAsp and ICGlu were identified by combined gas chromatography-mass spectrometry. Formation of ICGlu was dependent on the concentration of ethylene and the duration of the ethylene pretreatment. It is suggested that the catabolism of IAA to ICA may be one of the mechanisms by which ethylene endogenous IAA levels.

  17. The acropetal effects of indole-3-acetic acid in isolated shoot segments of Acer pseudoplatanus L. I. Growth responses of buds

    Directory of Open Access Journals (Sweden)

    Jacek A. Adamczyk

    2014-02-01

    Full Text Available The subject of this investigation were growth reactions of two opposite lateral buds of Acer pseudoplatanus L. stem sections in response to application of indole-3-acetic acid (IAA and other synthetic growth regulators below the buds. No effect of IAA upon the initiation of bud growth was noted, however, elongation of new shoots was inhibited. This acropetal effect of auxin was enhanced by simultaneous treatment with triiodobenzoic acid (TIBA or benzyladenine (BA. TIBA alone caused even stronger retardation of shoot growth. Exactly the opposite effect was produced by gibberellic acid (GA3 applied even 30 cm below the buds. In this case TIBA could reverse the effect of GA3 treatment. The results concerning acropetal effects of auxin suggest that some type of signalling system functions independently of the direct action of the exogenous IAA.

  18. The Difference of Sensitivity between BXPC-3 and K562 Cells by Treatments with Combination of Indole-3-acetic Acid and Horseradish Peroxidase

    Institute of Scientific and Technical Information of China (English)

    BEN Yali; LIU Deli; ZHU Dali; ZHU Derui; LUO Qin

    2006-01-01

    The difference of sensitivity to indole- 3-acetic acid ( IAA ) combined with horseradish peroxidase (HRP) in K562 and BXPC- 3 cells was investigated. The cell proliferation was determined by MTT assay. The cell cycle and apoptosis of K562 and BXPC- 3 cells were examined by a fluorescence flow cytometer (FCM) and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) respectively. The experimental results show that IAA and HRP could inhibit BXPC- 3 cell proliferation greatly compared with K562 cell during the first 48 h . The cell cycle was arrested predominantly at G2/ M phase in K562 and BXPC- 3 cells. The cell apoptosis of K562 and BXPC- 3 was induced by IAA/ HRP. There was a significant difference between the two cell lines since BXPC- 3 cells were more sensitive than K562 cells by treatments with combination of IAA and HRP.

  19. ELECTROSYNTHESES OF FREE-STANDING POLY(THIOPHENE-3-ACETIC ACID) FILM IN MIXED ELECTROLYTES OF BORON TRIFLUORIDE DIETHYL ETHERATE AND TRIFLUOROACETIC ACID

    Institute of Scientific and Technical Information of China (English)

    Yu He; Wen-juan Guo; Mei-shan Pei; Guang-you Zhang

    2012-01-01

    High quality free-standing poly(thiophene-3-acetic acid) (PTAA),a water-soluble polythiophene derivative,was successfully electrosynthesized in boron trifluoride diethyl etherate (BFEE) + 25% (by volume) trifluoroacetic acid (TFA) at lower potential (0.38 V versus Pt).The carboxyl group makes PTAA highly soluble in water,facilitating its potential application as a blue-light-emitting material.PTAA films with conductivity of 7 S cm-1 obtained from this medium showed better redox activity and thermal stability.The structure and morphology of the polymer were studied by UV-Vis,FT-IR,1H-NMR spectra and scanning electron microscopy,respectively.

  20. Screening of mercury-resistant and indole-3-acetic acid producing bacterial-consortium for growth promotion of Cicer arietinum L.

    Science.gov (United States)

    Amin, Aatif; Latif, Zakia

    2017-03-01

    Mercury resistant (Hg(R) ) bacteria were screened from industrial effluents and effluents-polluted rhizosphere soils near to districts Kasur and Sheikhupura, Pakistan. Out of 60 isolates, three bacterial strains, Bacillus sp. AZ-1, Bacillus cereus AZ-2, and Enterobacter cloacae AZ-3 showed Hg-resistance as 20 μg ml(-1) of HgCl2 and indole-3-acetic acid (IAA) production as 8-38 μg ml(-1) . Biochemical and molecular characterization of selected bacteria was confirmed by 16S ribotyping. Mercury resistant genes merA, merB, and merE of mer operon in Bacillus spp. were checked by PCR amplification. The merE gene involved in the transportation of elemental mercury (Hg(0) ) via cell membrane was first time cloned into pHLV vector and transformed in C43(DE3) Escherichia coli cells. The recombinant plasmid (pHLMerE) was expressed and purified by nickel (Ni(+2) ) affinity chromatography. Chromatographic techniques viz. thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and Gas chromatography-mass spectrometry (GC-MS) confirmed the presence of Indole-3-acetic acid (IAA) in supernatant of selected bacteria. The strain E. cloacae AZ-3 detoxified 88% of mercury (Hg(+2) ) from industrial effluent (p mercury amended soil with 20 μg ml(-1) HgCl2 resulted 80, 22, 64, 116, 50, 75, 30, and 100% increase as compared to control plants in seed germination, shoot and root length, shoot and root fresh weight, number of pods per plant, number of seeds and weight of seeds, respectively, of chickpea (Cicer arietinum L.) in pot experiments (p < 0.05).

  1. Study of the mechanism on the apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase

    Institute of Scientific and Technical Information of China (English)

    Song Tusheng; Yang Ling; Huang Chen; Liu Liying; Ni Lei; Wang Aiying; Luo Yu

    2007-01-01

    Objective To investigate the mechanisms of apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase. Methods Human leukemia cell line K562 were exposed to indole-3-acetic acid (IAA) at 20, 40, 60, 80 or 100 mol/L and horseradish peroxidase(HRP) at 1.2 g/mL for varying times. MTT assay was applied to detect the cell proliferation. Flow cytometry was performed to detect the arrest of cell cycle. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was used to measure apoptosis. 2, 7-dichlorofluorescin diacetate (DCFH-DA) uptake was measured to determine free radical by confocal microscope. Content of malondiadehyde (MDA) and activity of superoxide dismutase (SOD) were measured by biochemical methods. Results IAA/HRP initiated growth inhibition of K562 cells in a dose- and time-dependent manner. Flow cytometry revealed that cell cycle arrested at G1/G0 after 24 hours treatment. After 72 hours treatment, apoptotic rate of 100 mol/L IAA group increased to 43.9%, which was 5 times that of control(P<0.01). Content of MDA and activity of SOD increased respectively in treatments compared with control. Meanwhile, IAA/HRP stimulated the formation of free radical, which was increased by IAA concentration-dependently. Conclusion The combination of IAA and HRP can inhibit the growth of Human leukemia cell line K562 in vitro by inducing apoptosis which is associated with the increase of free radical. The combination of IAA and HRP might be a promising chemopreventive and chemotherapeutic agent against human leukemia.

  2. Studies on the Growth and Indole-3-Acetic Acid and Abscisic Acid Content of Zea mays Seedlings Grown in Microgravity 1

    Science.gov (United States)

    Schulze, Aga; Jensen, Philip J.; Desrosiers, Mark; Buta, J. George; Bandurski, Robert S.

    1992-01-01

    Measurements were made of the fresh weight, dry weight, dry weight-fresh weight ratio, free and conjugated indole-3-acetic acid, and free and conjugated abscisic acid in seedlings of Zea mays grown in darkness in microgravity and on earth. Imbibition of the dry kernels was for 17 h prior to launch. Growth was for 5 d at ambient orbiter temperature and at a chronic accelerational force of the order of 3 × 10−5 times earth gravity. Weights and hormone content of the microgravity seedlings were, with minor exceptions, not statistically different from seedlings grown in normal gravity. The tissues of the shuttle-grown plants appeared normal and the seedlings differed only in the lack of orientation of roots and shoots. These findings, based upon 5 d of growth in microgravity, cannot be extrapolated to growth in microgravity for weeks, months, and years, as might occur on a space station. Nonetheless, it is encouraging, for prospects of bioregeneration of the atmosphere and food production in a space station, that no pronounced differences in the parameters measured were apparent during the 5 d of plant seedling growth in microgravity. Images Figure 1 Figure 4 Figure 5 PMID:11537869

  3. A disposable electrochemical sensor for the determination of indole-3-acetic acid based on poly(safranine T)-reduced graphene oxide nanocomposite.

    Science.gov (United States)

    Gan, Tian; Hu, Chengguo; Chen, Zilin; Hu, Shengshui

    2011-07-15

    A disposable electrochemical sensor for the determination of indole-3-acetic acid (IAA) based on nanocomposites of reduced graphene oxide (rGO) and poly(safranine T) (PST) was reported. The sensor was prepared by coating a rGO film on a pre-anodized graphite electrode (AGE) through dipping-drying and electrodepositing a uniform PST layer on the rGO film. Scanning electron microscopic (SEM) and infrared spectroscopic (IR) characterizations indicated that PST-rGO formed a rough and crumpled composite film on AGE, which exhibited high sensitive response for the oxidation of IAA with 147-fold enhancement of the current signal compared with bare AGE. The voltammetric current has a good linear relationship with IAA concentration in the range 1.0×10(-7)-7.0×10(-6)M, with a low detection limit of 5.0×10(-8)M. This sensor has been applied to the determination of IAA in the extract samples of several plant leaves and the recoveries varied in the range of 97.71-103.43%.

  4. Interference-free determination of indole-3-acetic acid in two real systems using second-order calibration method coupled with excitation-emission matrix fluorescence.

    Science.gov (United States)

    Yan, Xiu-Fang; Wu, Hai-Long; Qing, Xiang-Dong; Sun, Yan-Mei; Yu, Ru-Qin

    2014-01-01

    In this work, a simple and practicable method that combines excitation-emission matrix (EEMs) fluorescence with a second-order calibration method based on parallel factor analysis-alternative least-squares (PARAFAC-ALS) algorithm was developed for the direct interference-free determination of indole-3-acetic acid (IAA) in two real systems, coconut water (CW) and coconut milk (CM). Although the excitation and emission profiles of IAA heavily overlapped with that of unknown interferents in the complex real systems, the actual contents and satisfactory recoveries were still obtained successfully. The contents of IAA in CW and CM were 10.8 ± 0.3 and 4.9 ± 0.2 μg mL(-1), respectively, which were consistent with those reported by LC-MS/MS assays in the reference material. The average spike recoveries of IAA in the validation set based on CW and CM were 102.1 ± 3.2 and 98.0 ± 1.9%, respectively. In addition, routine experiments were performed for establishing the validity of the assay to internationally accepted criteria.

  5. Altered architecture and enhanced drought tolerance in rice via the down-regulation of indole-3-acetic acid by TLD1/OsGH3.13 activation.

    Science.gov (United States)

    Zhang, Sheng-Wei; Li, Chen-Hui; Cao, Jia; Zhang, Yong-Cun; Zhang, Su-Qiao; Xia, Yu-Feng; Sun, Da-Ye; Sun, Ying

    2009-12-01

    Plant architecture is determined by genetic and developmental programs as well as by environmental factors. Sessile plants have evolved a subtle adaptive mechanism that allows them to alter their growth and development during periods of stress. Phytohormones play a central role in this process; however, the molecules responsible for integrating growth- and stress-related signals are unknown. Here, we report a gain-of-function rice (Oryza sativa) mutant, tld1-D, characterized by (and named for) an increased number of tillers, enlarged leaf angles, and dwarfism. TLD1 is a rice GH3.13 gene that encodes indole-3-acetic acid (IAA)-amido synthetase, which is suppressed in aboveground tissues under normal conditions but which is dramatically induced by drought stress. The activation of TLD1 reduced the IAA maxima at the lamina joint, shoot base, and nodes, resulting in subsequent alterations in plant architecture and tissue patterning but enhancing drought tolerance. Accordingly, the decreased level of free IAA in tld1-D due to the conjugation of IAA with amino acids greatly facilitated the accumulation of late-embryogenesis abundant mRNA compared with the wild type. The direct regulation of such drought-inducible genes by changes in the concentration of IAA provides a model for changes in plant architecture via the process of drought adaptation, which occurs frequently in nature.

  6. The role of calcium in growth induced by indole-3-acetic acid and gravity in the leaf-sheath pulvinus of oat (Avena sativa)

    Science.gov (United States)

    Brock, T. G.; Burg, J.; Ghosheh, N. S.; Kaufman, P. B.

    1992-01-01

    Leaf-sheath pulvini of excised segments from oat (Avena sativa L.) were induced to grow by treatment with 10 micromoles indole-3-acetic acid (IAA), gravistimulation, or both, and the effects of calcium, EGTA, and calcium channel blockers on growth were evaluated. Unilaterally applied calcium (10 mM CaCl2) significantly inhibited IAA-induced growth in upright pulvini but had no effect on growth induced by either gravity or gravity plus IAA. Calcium alone had no effect on upright pulvini. The calcium chelator EGTA alone (10 mM) stimulated growth in upright pulvini. However, EGTA had no effect on either IAA- or gravity-induced growth but slightly diminished growth in IAA-treated gravistimulated pulvini. The calcium channel blockers lanthanum chloride (25 mM), verapamil (2.5 mM), and nifedipine (2.5 mM) greatly inhibited growth as induced by IAA (> or = 50% inhibition) or IAA plus gravity (20% inhibition) but had no effect on gravistimulated pulvini. Combinations of channel blockers were similar in effect on IAA action as individual blockers. Since neither calcium ions nor EGTA significantly affected the graviresponse of pulvini, we conclude that apoplastic calcium is unimportant in leaf-sheath pulvinus gravitropism. The observation that calcium ions and calcium channel blockers inhibit IAA-induced growth, but have no effect on gravistimulated pulvini, further supports previous observations that gravistimulation alters the responsiveness of pulvini to IAA.

  7. Indole-3-acetic acid (IAA) production in symbiotic and non-symbiotic nitrogen-fixing bacteria and its optimization by Taguchi design.

    Science.gov (United States)

    Shokri, Dariush; Emtiazi, Giti

    2010-09-01

    Production of Indole-3-acetic acid (IAA) in 35 different symbiotic and non-symbiotic nitrogen-fixing bacteria strains isolated from soil and plant roots was studied and assayed by chromatography and colorimetric methods. These bacteria included Agrobacterium, Paenibacillus, Rhizobium, Klebsiella oxytoca, and Azotobacter. The best general medium and synergism effects of isolates for IAA production were investigated. Effects of different variables containing physical parameters and key media components and optimization of condition for IAA production were performed using the Design of Experiments. Qualitek-4 (W32b) software for automatic design and analysis of the experiments, both based on Taguchi method was used. The results showed that Rhizobium strains, symbiotic, and Paenibacillus non-symbiotic bacteria yielded the highest concentrations of IAA (in the range of 5.23-0.27 and 4.90-0.19 ppm IAA/mg biomass, respectively) and IAA production was increased by synergism effect of them. Yeast Extract Mannitol medium supplemented with L-tryptophan was the best general medium for IAA production. The analysis of experimental data using Taguchi method indicated that nitrogen source is very prominent variable in affecting the yield and mannitol as carbon source, potassium nitrate (1%), and L-tryptophan (3 g/l) as nitrogen sources after 72-h incubation at 30 degrees C were the optimum conditions for production of IAA. 5.89 ppm IAA/mg biomass was produced under these optimal conditions.

  8. Stable isotope labeling, in vivo, of D- and L-tryptophan pools in lemna gibba and the low incorporation of label into indole-3-acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Baldi, B.G. (Dept. of Agriculture, Beltsville, MD (USA)); Maher, B.R. (Univ. of Maryland, College Park (USA)); Slovin, J.P.; Cohen, J.D. (Dept. of Agriculture, Beltsville, MD (USA) Univ. of Maryland, College Park (USA))

    1991-04-01

    The authors present evidence that the role of tryptophan and other potential intermediates in the pathways that could lead to indole derivatives needs to be reexamined. Two lines of Lemna gibba were tested for uptake of ({sup 15}N-indole)-labeled tryptophan isomers and incorporation of that label into free indole-3-acetic acid (IAA). Both lines required levels of L-({sup 15}N)tryptophan 2 to 3 orders of magnitude over endogenous levels in order to obtain measurable incorporation of label into IAA. Labeled L-tryptophan was extractable from plant tissue after feeding and showed no measurable isomerization into D-tryptophan. D-({sup 15}N)trytophan supplied to Lemna at rates of approximately 400 times excess of endogenous D-tryptophan levels (to yield an isotopic enrichment equal to that which allowed detection of the incorporation of L-tryptophan into IAA), did not result in measurable incorporation of label into free IAA. These results demonstrate that L-tryptophan is a more direct precursor to IAA than the D isomer and suggest (a) that the availability of tryptophan in vivo is not a limiting factor in the biosynthesis of IAA, thus implying that other regulatory mechanisms are in operation and (b) that L-tryptophan also may not be a primary precursor to IAA in plants.

  9. Attempting to monitor the incorporation of deuterium into indole-3-acetic acid and tryptophan in Zea mays grown on deuterium oxide labeled water

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, P.J.; Bandurski, R.S. (Michigan State Univ., East Lansing (USA))

    1989-04-01

    We are attempting to determine when seedlings of Zea mays sweet corn, var. Silver Queen begin de novo biosynthesis of tryptophan and indole-3-acetic acid (IAA). We wish to use the general precursor, deuterium labeled water, to minimize assumptions as to the biosynthetic route. Protium in positions 2, 4, 5, 6 7 of the indole ring are non-exchangeable. IAA and tryptophan synthesized via the shikimic acid pathway would contain deuterium in one or more of these positions . The protium on the indene nitrogen, the carboxyl, the amino group, or the protium alpha to the carboxyl exchange readily and so are removed prior to analysis by base catalyzed exchange. The IAA, or trypotophan, is then purified by DEAE, Dowex 50, and two HPLC steps. IAA is methylated with diazomethane and analyzed by GC/MS. Trytophan is acetylated with triethylamine-acetic anhydride and then methylated with diazomethane and analyzed by GC/MS. Results of these studies on plants grown for varying lengths of time and under various light and nutrient conditions will be reported.

  10. Influence of tryptophan and indole-3-acetic acid on starch accumulation in the synthetic mutualistic Chlorella sorokiniana-Azospirillum brasilense system under heterotrophic conditions.

    Science.gov (United States)

    Palacios, Oskar A; Choix, Francisco J; Bashan, Yoav; de-Bashan, Luz E

    2016-06-01

    This study measured the relations between tryptophan production, the phytohormone indole-3-acetic acid (IAA) and the metabolism and accumulation of starch during synthetic mutualism between the microalgae Chlorella sorokiniana and the microalgae growth-promoting bacteria Azospirillum brasilense, created by co-immobilization in alginate beads. Experiments used two wild-type A. brasilense strains (Cd and Sp6) and an IAA-attenuated mutant (SpM7918) grown under nitrogen-replete and nitrogen-starved conditions tested under dark, heterotrophic and aerobic growth conditions. Under all incubating conditions, C. sorokiniana, but not A. brasilense, produced tryptophan. A significant correlation between IAA-production by A. brasilense and starch accumulation in C. sorokiniana was found, since the IAA-attenuated mutant was not producing increased starch levels. The highest ADP-glucose pyrophosphorylase (AGPase) activity, starch content and glucose uptake were found during the interaction of A. brasilense wild type strains with the microalgae. When the microalgae were grown alone, they produced only small amounts of starch. Supplementation with synthetic IAA to C. sorokiniana grown alone enhanced the above parameters, but only transiently. Activity of α-amylase decreased under nitrogen-replete conditions, but increased under nitrogen-starved conditions. In summary, this study demonstrated that, during synthetic mutualism, the exchange of tryptophan and IAA between the partners is a mechanism that governs several changes in starch metabolism of C. sorokiniana, yielding an increase in starch content.

  11. Indole-3-acetic acid (IAA) producing Pseudomonas isolates inhibit seed germination and α-amylase activity in durum wheat (Triticum turgidum L.)

    Energy Technology Data Exchange (ETDEWEB)

    Tabatabaei, S.; Ehsanzadeh, P.; Etesami, H.; Alikhani, H.A.; Glick, B.R.

    2016-11-01

    The role of plant-associated bacteria in plant physiology and metabolism is well documented, but little has been known about the roles played by Pseudomonas in durum wheat (Triticum turgidum L. var durum) growth and development. An in vitroexperiment was conducted to observe the effect of the inoculation of four indole-3-acetic acid (IAA)-producing Pseudomonas isolates and exogenous IAA on seed germination traits and α-amylase activity of durum wheat. The results showed inoculation with all bacterial isolates led to a decrease in the germination percent, although the extent of the depression varied with the isolate. A significant relationship between concentrations of bacterial IAA and the germination inhibition percent in durum wheat seeds by different bacteria strains was observed. The results of this assay showed the effect of bacterial isolates on α-amylase activity after six and 8 days of inoculation was significant, while effect of these isolates on α-amylase activity after two and 4 days of inoculation was not meaningful. In addition, the exogenously applied IAA displayed a concentration-dependent effect on seed germination attributes and α-amylase activity, consistent with the possibility that the inhibitory effect of bacterial inoculation on seed germination was in consequence of bacteria-produced IAA. Therefore, it may suggested that the inhibitory role of IAA in seed germination and α-amylase activity should be taken into account during the screening of IAA-producing Pseudomonas isolates for durum wheat growth promoting agents. (Author)

  12. Indole-3-acetic acid (IAA) biosynthesis in the smut fungus Ustilago maydis and its relevance for increased IAA levels in infected tissue and host tumour formation.

    Science.gov (United States)

    Reineke, Gavin; Heinze, Bernadette; Schirawski, Jan; Buettner, Hermann; Kahmann, Regine; Basse, Christoph W

    2008-05-01

    Infection of maize (Zea mays) plants with the smut fungus Ustilago maydis is characterized by excessive host tumour formation. U. maydis is able to produce indole-3-acetic acid (IAA) efficiently from tryptophan. To assess a possible connection to the induction of host tumours, we investigated the pathways leading to fungal IAA biosynthesis. Besides the previously identified iad1 gene, we identified a second indole-3-acetaldehyde dehydrogenase gene, iad2. Deltaiad1Deltaiad2 mutants were blocked in the conversion of both indole-3-acetaldehyde and tryptamine to IAA, although the reduction in IAA formation from tryptophan was not significantly different from Deltaiad1 mutants. To assess an influence of indole-3-pyruvic acid on IAA formation, we deleted the aromatic amino acid aminotransferase genes tam1 and tam2 in Deltaiad1Deltaiad2 mutants. This revealed a further reduction in IAA levels by five- and tenfold in mutant strains harbouring theDeltatam1 andDeltatam1Deltatam2 deletions, respectively. This illustrates that indole-3-pyruvic acid serves as an efficient precursor for IAA formation in U. maydis. Interestingly, the rise in host IAA levels upon U. maydis infection was significantly reduced in tissue infected with Deltaiad1Deltaiad2Deltatam1 orDeltaiad1Deltaiad2Deltatam1Deltatam2 mutants, whereas induction of tumours was not compromised. Together, these results indicate that fungal IAA production critically contributes to IAA levels in infected tissue, but this is apparently not important for triggering host tumour formation.

  13. Orchid-associated bacteria produce indole-3-acetic acid, promote seed germination, and increase their microbial yield in response to exogenous auxin.

    Science.gov (United States)

    Tsavkelova, Elena A; Cherdyntseva, Tatiana A; Klimova, Svetlana Yu; Shestakov, Andrey I; Botina, Svetlana G; Netrusov, Alexander I

    2007-12-01

    Germination of orchid seeds is a complex process. In this paper we focus on interactions between the host-plant and its bacterial partners via indole-3-acetic acid (IAA). Originally isolated from the roots of the epiphytic orchid Dendrobium moschatum, the strains of Rhizobium, Microbacterium, Sphingomonas, and Mycobacterium genera were among the most active IAA producers. Addition of exogenous tryptophan significantly enhanced auxin formation both in mineral and complex media. The presence of IAA and indole-3-acetaldehyde was confirmed by HPLC. Indole-3-pyruvic and indole-3-lactic acids were also detected in supernatants of culture filtrates of Sphingomonas sp., Rhizobium sp., and Microbacterium sp., while indole-3-acetamide was identified only in Mycobacterium sp. Some concentration- and strain-dependent effects of exogenous IAA on bacterial development were also established. Treatment of the cultures with 10 and 100 microg/ml of auxin resulted in an increase in microbial yield. None of the investigated strains was able to utilize IAA as a source of carbon and energy. Furthermore, inoculation of D. moschatum seeds with Sphingomonas sp. and Mycobacterium sp. resulted in considerable enhancement of orchid seeds germination. This growth-promoting activity was observed in the absence of any plant growth stimulators or mycorrhizal fungi, usually required for orchid germination.

  14. Tn5-mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu62

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5-insertion library of A. brasilense Yu62 was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A24, were isolated. The sequence analysis of loci tagged showed that the Tn5-1063a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time, atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA,atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

  15. Both Free Indole-3-Acetic Acid and Photosynthetic Performance are Important Players in the Response of Medicago truncatula to Urea and Ammonium Nutrition Under Axenic Conditions

    Science.gov (United States)

    Esteban, Raquel; Royo, Beatriz; Urarte, Estibaliz; Zamarreño, Ángel M.; Garcia-Mina, José M.; Moran, Jose F.

    2016-01-01

    We aimed to identify the early stress response and plant performance of Medicago truncatula growing in axenic medium with ammonium or urea as the sole source of nitrogen, with respect to nitrate-based nutrition. Biomass measurements, auxin content analyses, root system architecture (RSA) response analyses, and physiological parameters were determined. Both ammonium and ureic nutrition severely affected the RSA, resulting in changes in the main elongation rate, lateral root development, and insert position from the root base. The auxin content decreased in both urea- and ammonium-treated roots; however, only the ammonium-treated plants were affected at the shoot level. The analysis of chlorophyll a fluorescence transients showed that ammonium affected photosystem II, but urea did not impair photosynthetic activity. Superoxide dismutase isoenzymes in the plastids were moderately affected by urea and ammonium in the roots. Overall, our results showed that low N doses from different sources had no remarkable effects on M. truncatula, with the exception of the differential phenotypic root response. High doses of both ammonium and urea caused great changes in plant length, auxin contents and physiological measurements. Interesting correlations were found between the shoot auxin pool and both plant length and the “performance index” parameter, which is obtained from measurements of the kinetics of chlorophyll a fluorescence. Taken together, these data demonstrate that both the indole-3-acetic acid pool and performance index are important components of the response of M. truncatula under ammonium or urea as the sole N source. PMID:26909089

  16. The Overproduction of Indole-3-Acetic Acid (IAA) in Endophytes Upregulates Nitrogen Fixation in Both Bacterial Cultures and Inoculated Rice Plants.

    Science.gov (United States)

    Defez, Roberto; Andreozzi, Anna; Bianco, Carmen

    2017-02-14

    Endophytic bacteria from roots and leaves of rice plants were isolated and identified in order to select the diazotrophs and improve their nitrogen-fixing abilities. The nitrogen-fixing endophytes were identified by PCR amplification of the nifH gene fragment. For this purpose, two isolates, Enterobacter cloacae RCA25 and Klebsiella variicola RCA26, and two model bacteria (Herbaspirillum seropedicae z67 and Sinorhizobium fredii NGR234) were transformed to increase the biosynthesis of the main plant auxin indole-3-acetic acid (IAA). A significant increase in the production of IAA was observed for all strains. When the expression of nifH gene and the activity of the nitrogenase enzyme were analyzed in liquid cultures, we found that they were positively affected in the IAA-overproducing endophytes as compared to the wild-type ones. Rice plants inoculated with these modified strains showed a significant upregulation of the nitrogenase activity when plants infected with the wild-type strains were used as reference. Similar results were obtained too with common bean plants infected with the S. fredii NGR234 strain. These findings suggest that IAA overproduction improves nitrogen-fixing apparatus of endophytic bacteria both in liquid cultures and in inoculated host plants. The present study highlights new perspectives to enhance nitrogen-fixing ability in non-legume crops. These strains could be used as bioinoculants to improve the growth and the yield of agricultural crops, offering an alternative to the use of chemical nitrogen fertilizers.

  17. Alternative mechanism for the evaluation of indole-3-acetic acid (IAA) production by Azospirillum brasilense strains and its effects on the germination and growth of maize seedlings.

    Science.gov (United States)

    Masciarelli, Oscar; Urbani, Lucia; Reinoso, Herminda; Luna, Virginia

    2013-10-01

    We evaluated the production of indole-3-acetic acid (IAA) by Azospirillum brasilense strains in vitro (cell culture supernatants) and in vivo (stems and roots of maize seedlings) to clarify the role of this phytohormone as a signaling and effector molecule in the symbiotic interaction between maize and A. brasilense. The three strains all showed IAA production when cultured in NFb medium supplemented with 100 μg/ml L-tryptophan. The level of IAA production was 41.5 μg/ml for Yu62, 12.9 μg/ml for Az39, and 0.15 μg/ml for ipdC-. The release of IAA into culture medium by the bacteria appeared to be the main activator of the early growth promotion observed in the inoculated maize seedlings. The application of supernatants with different IAA contents caused significant differences in the seedling growth. This observation provides the basis for novel technological tools for effective quality control procedures on inoculants. The approach described can be incorporated into different inoculation methods, including line sowing, downspout, and foliar techniques, and increase the sustainability of symbiotic plant-bacteria systems.

  18. Antifungal and sprout regulatory bioactivities of phenylacetic acid, indole-3-acetic acid, and tyrosol isolated from the potato dry rot suppressive bacterium Enterobacter cloacae S11:T:07.

    Science.gov (United States)

    Slininger, P J; Burkhead, K D; Schisler, D A

    2004-12-01

    Enterobacter cloacae S11: T:07 (NRRL B-21050) is a promising biological control agent that has significantly reduced both fungal dry rot disease and sprouting in laboratory and pilot potato storages. The metabolites phenylacetic acid (PAA), indole-3-acetic acid (IAA), and tyrosol (TSL) were isolated from S11:T:07 liquid cultures provided with three different growth media. The bioactivities of these metabolites were investigated via thin-layer chromatography bioautography of antifungal activity, wounded potato assays of dry rot suppressiveness, and cored potato eye assays of sprout inhibition. Relative accumulations of PAA, IAA, and TSL in cultures were nutrient dependent. For the first time, IAA, TSL, and PAA were shown to have antifungal activity against the dry rot causative pathogen Gibberella pulicaris, and to suppress dry rot infection of wounded potatoes. Disease suppression was optimal when all three metabolites were applied in combination. Dosages of IAA that resulted in disease suppression also resulted in sprout inhibition. These results suggest the potential for designing culture production and formulation conditions to achieve a dual purpose biological control agent able to suppress both dry rot and sprouting of stored potatoes.

  19. Effects of Indole-3-Acetic Acid on Germination in Lead Polluted Petri Dish of Citrullus lanatus (Thunberg Matsumura and Nakai, Cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Matthew Chidozie Ogwu

    2015-12-01

    Full Text Available Watermelon, Citrullus lanatus (Thunberg Matsumura and Nakai is a tropical fruit vegetable. Indole-3-acetic acid (IAA is a popular phytohormone while lead (Pb is a common environmental pollutant in urban and sub-urban centers. C. lanatus were obtained from Benin City with a view to study the effects of IAA on their germination in Pb polluted environment.  Germination percentage without IAA and Pb treatment in petri dish was significant after ten days. Hastened germination was observed when IAA and lead were used. About 100 % germination was recorded after seven days. This suggests that water melon seeds can initiate growth even in lead polluted environment. Optimum level of 5 ppm IAA with the different levels of lead treatments may be recommended. Most important was that higher concentrations of Pb in the control (without IAA did not inhibit seedling shoot nor root growth. Longest seedling shoot length (cm was 10.33 ± 1.24 and 12.13 ± 2.06 on the seventh and eighth day respectively with the combined treatment levels of 1 ppm IAA and 15 ppm Pb. On the ninth day, 15.27 ± 0.96 was obtained from 1 ppm IAA and 20 ppm Pb. Longest seedling root length (cm values were recorded from the combined treatment levels of 0 ppm IAA and 10 ppm Pb for the seventh (9.10 ± 0.47 and ninth (10.37 ± 1.81 day respectively and 0 ppm and 15 ppm Pb on the eighth (9.37 ± 0.84 day. Significant means were also obtained with the treatment level of 0 and 20 ppm IAA. This present study suggest the germination of C. lanatus under Pb polluted environment may be rescued with optimum IAA.

  20. Molecular dynamics simulations of the auxin-binding protein 1 in complex with indole-3-acetic acid and naphthalen-1-acetic acid.

    Science.gov (United States)

    Grandits, Melanie; Oostenbrink, Chris

    2014-10-01

    Auxin-binding protein 1 (ABP1) is suggested to be an auxin receptor which plays an important role in several processes in green plants. Maize ABP1 was simulated with the natural auxin indole-3-acetic acid (IAA) and the synthetic analog naphthalen-1-acetic acid (NAA), to elucidate the role of the KDEL sequence and the helix at the C-terminus. The KDEL sequence weakens the intermolecular interactions between the monomers but stabilizes the C-terminal helix. Conformational changes at the C-terminus occur within the KDEL sequence and are influenced by the binding of the simulated ligands. This observation helps to explain experimental findings on ABP1 interactions with antibodies that are modulated by the presence of auxin, and supports the hypothesis that ABP1 acts as an auxin receptor. Stable hydrogen bonds between the monomers are formed between Glu40 and Glu62, Arg10 and Thr97, Lys39, and Glu62 in all simulations. The amino acids Ile22, Leu25, Trp44, Pro55, Ile130, and Phe149 are located in the binding pocket and are involved in hydrophobic interactions with the ring system of the ligand. Trp151 is stably involved in a face to end interaction with the ligand. The calculated free energy of binding using the linear interaction energy approach showed a higher binding affinity for NAA as compared to IAA. Our simulations confirm the asymmetric behavior of the two monomers, the stronger interaction of NAA than IAA and offers insight into the possible mechanism of ABP1 as an auxin receptor.

  1. pH-Triggered Controllable Release of Silver-Indole-3 Acetic Acid Complexes from Mesoporous Silica Nanoparticles (IBN-4) for Effectively Killing Malignant Bacteria.

    Science.gov (United States)

    Kuthati, Yaswanth; Kankala, Ranjith Kumar; Lin, Shi-Xiang; Weng, Ching-Feng; Lee, Chia-Hung

    2015-07-06

    An efficient approach for the antimicrobial agent delivery specifically at acidic pH has been proposed. At the outset, functionalized mesoporous nanoparticles (NPs) were examined to verify the success of synthesis while considering the structural properties by various characterizations. The NPs were immobilized with silver-indole-3 acetic acid hydrazide (IAAH-Ag) complexes via a pH-sensitive hydrazone bond, which functioned as a model drug. When the transitional metal complexes with IBN-4-IAAH-Ag were exposed to acidic pH (near pH 5.0), the silver ions were preferentially released (70%) in a controlled manner up to 12 h by pH-sensitive denial of hydrazone bonds. In contrary, a low drug release (about 25%) was seen in physiological buffer (pH 7.4) demonstrating the pH sensitive release of this drug. Furthermore, the antibacterial efficacy of this unique structured sample was tested against the planktonic cells and biofilms of Gram-positive and Gram-negative bacteria with field emission scanning electron microscope in turn measuring the growth curves, formation of lethal reactive oxygen species, protein leakage, and DNA damage. The synthesized pH-sensitive IAAH-Ag complex was found to have high antimicrobial efficacy against multidrug resistant clinical isolates both in planktonic and biofilm states. Going forward, the synthesized nanoconjugates proved a good in vivo efficacy in treating the bacterial infection of mice. These new metal complex-conjugated NPs through a pH-sensitive hydrazone bond opened up a new avenue for the design and synthesis of the next generation antibacterial agents, which would act as an alternative to antibiotics.

  2. A novel tool for studying auxin-metabolism: the inhibition of grapevine indole-3-acetic acid-amido synthetases by a reaction intermediate analogue.

    Directory of Open Access Journals (Sweden)

    Christine Böttcher

    Full Text Available An important process for the regulation of auxin levels in plants is the inactivation of indole-3-acetic acid (IAA by conjugation to amino acids. The conjugation reaction is catalysed by IAA-amido synthetases belonging to the family of GH3 proteins. Genetic approaches to study the biological significance of these enzymes have been hampered by large gene numbers and a high degree of functional redundancy. To overcome these difficulties a chemical approach based on the reaction mechanism of GH3 proteins was employed to design a small molecule inhibitor of IAA-amido synthetase activity. Adenosine-5'-[2-(1H-indol-3-ylethyl]phosphate (AIEP mimics the adenylated intermediate of the IAA-conjugation reaction and was therefore proposed to compete with the binding of MgATP and IAA in the initial stages of catalysis. Two grapevine IAA-amido synthetases with different catalytic properties were chosen to test the inhibitory effects of AIEP in vitro. GH3-1 has previously been implicated in the grape berry ripening process and is restricted to two amino acid substrates, whereas GH3-6 conjugated IAA to 13 amino acids. AIEP is the most potent inhibitor of GH3 enzymes so far described and was shown to be competitive against MgATP and IAA binding to both enzymes with K(i-values 17-68-fold lower than the respective K(m-values. AIEP also exhibited in vivo activity in an ex planta test system using young grape berries. Exposure to 5-20 µM of the inhibitor led to decreased levels of the common conjugate IAA-Asp and reduced the accumulation of the corresponding Asp-conjugate upon treatment with a synthetic auxin. AIEP therefore represents a novel chemical probe with which to study IAA-amido synthetase function.

  3. The ipdC, hisC1 and hisC2 genes involved in indole-3-acetic production used as alternative phylogenetic markers in Azospirillum brasilense.

    Science.gov (United States)

    Jijón-Moreno, Saúl; Marcos-Jiménez, Cynthia; Pedraza, Raúl O; Ramírez-Mata, Alberto; de Salamone, I García; Fernández-Scavino, Ana; Vásquez-Hernández, Claudia A; Soto-Urzúa, Lucia; Baca, Beatriz E

    2015-06-01

    Plant growth-promoting bacteria of the genus Azospirillum are present in the rhizosphere and as endophytes of many crops. In this research we studied 40 Azospirillum strains isolated from different plants and geographic regions. They were first characterized by 16S rDNA restriction analysis, and their phylogenetic position was established by sequencing the genes 16S rDNA, ipdC, hisC1, and hisC2. The latter three genes are involved in the indole-3-pyruvic acid (IPyA) biosynthesis pathway of indole-3-acetic acid (IAA). Furthermore, the suitability of the 16S-23S rDNA intergenic spacer sequence (IGS) for the differentiation of closely related Azospirillum taxa and development of PCR protocols allows for specific detection of strains. The IGS-RFLP analysis enabled intraspecies differentiation, particularly of Azospirillum brasilense and Azospirillum lipoferum strains. Results demonstrated that the ipdC, hisC1, and hisC2 genes are highly conserved in all the assessed A. brasilense isolates, suggesting that these genes can be used as an alternative phylogenetic marker. In addition, IAA production determined by HPLC ranged from 0.17 to 98.2 μg mg(-1) protein. Southern hybridization with the A. brasilense ipdC gene probe did not show, a hybridization signal with A. lipoferum, Azospirillum amazonense, Azospirillum halopreferans and Azospirillum irakense genomic DNA. This suggests that these species produce IAA by other pathways. Because IAA is mainly synthesized via the IPyA pathway in A. brasilense strains, a species that is used worldwide in agriculture, the identification of ipdC, hisC1, and hisC2 genes by PCR may be suitable for selecting exploitable strains.

  4. Epibrassinolide induces changes in indole-3-acetic acid, abscisic acid and polyamine concentrations and enhances antioxidant potential of radish seedlings under copper stress.

    Science.gov (United States)

    Choudhary, Sikander Pal; Bhardwaj, Renu; Gupta, Bishan Datt; Dutt, Prabhu; Gupta, Rajinder Kumar; Biondi, Stefania; Kanwar, Mukesh

    2010-11-01

    In the present study, the effects of epibrassinolide (EBL) on indole-3-acetic acid (IAA), abscisic acid (ABA) and polyamine (PA) tissue concentrations and antioxidant potential of 7-day-old Raphanus sativus L. cv. 'Pusa chetki' seedlings grown under Cu stress were investigated. EBL treatment alone or in combination with Cu enhanced free and bound IAA titers when compared with the metal alone. Modest increases in free and bound ABA contents were observed for EBL treatment alone. However, the combination of EBL with Cu caused major increases in both forms of ABA, over Cu alone. Among the PAs analyzed, only putrescine and cadaverine concentrations were enhanced by EBL treatment alone. By contrast, a significant decline in putrescine and spermine contents was found in seedlings treated with EBL plus Cu. EBL treatments alone or in combination with Cu enhanced activities of guaiacol peroxidase (EC1.11.1.7), catalase (EC 1.11.1.6), superoxide dismutase (EC 1.15.1.1) and glutathione reductase (EC 1.6.4.2) and protein contents in comparison with metal and control treatments. A major decrease in malondialdehyde content was also recorded for EBL treatments with or without Cu. An increase in phytochelatin content was also observed in seedlings treated with EBL alone or in combination with Cu. Major improvement in radical scavenging activities, as attested by the antioxidant activity assay using DPPH (1,1-diphenylpicrylhydrazyl), and elevated deoxyribose and reducing powers, along with increased contents of ascorbic acid, total phenols and proline, also suggest a major influence of EBL application in mitigating copper-induced oxidative stress in radish seedlings. Copyright © Physiologia Plantarum 2010.

  5. Metabolism of (1-(13)C) glucose and (2-(13)C, 2-(2)H(3)) acetate in the neuronal and glial compartments of the adult rat brain as detected by [(13)C, (2)H] NMR spectroscopy.

    Science.gov (United States)

    Chapa, F; Cruz, F; García-Martín, M L; García-Espinosa, M A; Cerdán, S

    2000-01-01

    Ex vivo ¿(13)C, (2)H¿ NMR spectroscopy allowed to estimate the relative sizes of neuronal and glial glutamate pools and the relative contributions of (1-(13)C) glucose and (2-(13)C, 2-(2)H(3)) acetate to the neuronal and glial tricarboxylic acid cycles of the adult rat brain. Rats were infused during 60 min in the right jugular vein with solutions containing (2-(13)C, 2-(2)H(3)) acetate and (1-(13)C) glucose or (2-(13)C, 2-(2)H(3)) acetate only. At the end of the infusion the brains were frozen in situ and perchloric acid extracts were prepared and analyzed by high resolution (13)C NMR spectroscopy (90.5 MHz). The relative sizes of the neuronal and glial glutamate pools and the contributions of acetyl-CoA molecules derived from (2-(13)C, (2)H(3)) acetate or (1-(13)C) glucose entering the tricarboxylic acid cycles of both compartments, could be determined by the analysis of (2)H-(13)C multiplets and (2)H induced isotopic shifts observed in the C4 carbon resonances of glutamate and glutamine. During the infusions with (2-(13)C, 2-(2)H(3)) acetate and (1-(13)C) glucose, the glial glutamate pool contributed 9% of total cerebral glutamate being derived from (2-(13)C, 2-(2)H(3)) acetyl-CoA (4%), (2-(13)C) acetyl-CoA (3%) and recycled (2-(13)C, 2-(2)H) acetyl-CoA (2%). The neuronal glutamate pool accounted for 91% of the total cerebral glutamate being mainly originated from (2-(13)C) acetyl-CoA (86%) and (2-(13)C, 2-(2)H) acetyl-CoA (5%). During the infusions of (2-(13)C, 2-(2)H(3)) acetate only, the glial glutamate pool contributed 73% of the cerebral glutamate, being derived from (2-(13)C, 2-(2)H(3)) acetyl-CoA (36%), (2-(13)C, 2-(2)H) acetyl-CoA (27%) and (2-(13)C) acetyl-CoA (10%). The neuronal pool contributed 27% of cerebral glutamate being formed from (2-(13)C) acetyl-CoA (11%) and recycled (2-(13)C, 2-(2)H) acetyl-CoA (16%). These results illustrate the potential of ¿(13)C, (2)H¿ NMR spectroscopy as a novel approach to investigate substrate selection and

  6. Validation of a multi-analyte HPLC-DAD method for determination of uric acid, creatinine, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid and 2-methylhippuric acid in human urine.

    Science.gov (United States)

    Remane, Daniela; Grunwald, Soeren; Hoeke, Henrike; Mueller, Andrea; Roeder, Stefan; von Bergen, Martin; Wissenbach, Dirk K

    2015-08-15

    During the last decades exposure sciences and epidemiological studies attracts more attention to unravel the mechanisms for the development of chronic diseases. According to this an existing HPLC-DAD method for determination of creatinine in urine samples was expended for seven analytes and validated. Creatinine, uric acid, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid, and 2-methylhippuric acid were separated by gradient elution (formate buffer/methanol) using an Eclipse Plus C18 Rapid Resolution column (4.6mm×100mm). No interfering signals were detected in mobile phase. After injection of blank urine samples signals for the endogenous compounds but no interferences were detected. All analytes were linear in the selected calibration range and a non weighted calibration model was chosen. Bias, intra-day and inter-day precision for all analytes were below 20% for quality control (QC) low and below 10% for QC medium and high. The limits of quantification in mobile phase were in line with reported reference values but had to be adjusted in urine for homovanillic acid (45mg/L), niacinamide 58.5(mg/L), and indole-3-acetic acid (63mg/L). Comparison of creatinine data obtained by the existing method with those of the developed method showing differences from -120mg/L to +110mg/L with a mean of differences of 29.0mg/L for 50 authentic urine samples. Analyzing 50 authentic urine samples, uric acid, creatinine, hippuric acid, and 2-methylhippuric acid were detected in (nearly) all samples. However, homovanillic acid was detected in 40%, niacinamide in 4% and indole-3-acetic acid was never detected within the selected samples.

  7. Changes in the level of ( sup 14 C)indole-3-acetic acid and ( sup 14 C)indoleacetylaspartic acid during root formation in mung bean cuttings. [Vigna radiata

    Energy Technology Data Exchange (ETDEWEB)

    Norcini, J.G.; Heuser, C.W. (Pennsylvania State Univ., University Park (USA))

    1988-04-01

    Changes in the levels of ({sup 14}C)indole-3-acetic acid (IAA) and ({sup 14}C)indoleacetylaspartic acid (IAAsp) were examined during adventitious root formation in mung bean (Vigna radiata (L.) R. Wilcz. Berken) stem cuttings. IAAsp was identified by GC-MS as the primary conjugate in IAA-treated cuttings. During root formation in IAA-treated cuttings, the level of ({sup 14}C)IAAsp increased rapidly the first day and then declined; ({sup 14}C)IAA was rapidly metabolized and not detected after 12 hours.

  8. 导数同步荧光法同时测定吲哚-3-乙酸和萘氧乙酸%Simultaneous determination of 2-Naphthoxyacetic acid and indole-3-acetic acid by first derivative synchronous fluorescence spectroscopy

    Institute of Scientific and Technical Information of China (English)

    刘香香; 万益群

    2013-01-01

    A simple,rapid,sensitive and selective method for simultaneous determination of 2-naphthoxyacetic acid (BNOA) and indole-3-acetic acid (IAA) in mixtures has been developed using derivative synchronous fluorescence spectroscopy.The synchronous fluorescence spectra were obtained with △λ =100 nm in a pH 8.5 NaH2PO4-NaOH buffer solution,and the detected wavelengths of quantitative analysis were set at 239 nm for BNOA and 293 nm for IAA,respectively.The overlapped fluorescence spectra were well separated by the synchronous derivative method.Under optimized conditions,the limits of detection (LOD) were 0.003 μg/mL for BNOA and 0.012 μg/mL for IAA,respectively.This method is simple and expeditious,and it has been successfully applied to the determination of 2-naphthoxyacetic acid and indole-3-acetic acid in fruit juice samples with satisfactory results.%采用荧光光谱法同时测定混合物体系中萘氧乙酸(BNOA)和吲哚-3-乙酸(IAA)两种植物激素.在pH 8.5的条件下,以水为溶剂,选择△λ=100nm,在200~500 nm的波长范围对两者的混合物进行了同步荧光光谱扫描,并做一阶导数处理,对其进行定量分析.BNOA和IAA的线性范围是0.01 ~0.3 μg/mL和0.045~0.64 μg/mL,检出限分别为0.003 μg/mL和0.012 μg/mL.方法用于果蔬中BNOA和IAA的同时检测,效果良好.该法可作为植物激素快速检测方法.

  9. Effects of two plant growth regulators, indole-3-acetic acid and β-naphthoxyacetic acid, on genotoxicity in Drosophila SMART assay and on proliferation and viability of HEK293 cells from the perspective of carcinogenesis.

    Science.gov (United States)

    Karadeniz, Asuman; Kaya, Bülent; Savaş, Burhan; Topcuoğlu, Ş Fatih

    2011-10-01

    In this study, the mutagenic and recombinogenic effects of indole-3-acetic acid (IAA), a plant growth regulator naturally synthesized in plants but produced synthetically, and β-naphthoxyacetic acid (BNOA), a synthetic plant growth regulator widely used in agricultural regions, were investigated using the somatic mutation and recombination test (SMART) in Drosophila wings. The effect of the same plant growth regulators against the proliferation and viability of a human immortalized embryonic kidney HEK293 cells which is at the early stage of carcinogenesis were also examined with MTT and trypan-blue exclusion assays. For the SMART assay, two different crosses were used: a standard and a high-bioactivation (HB) cross, involving the flare-3 and the multiple wing hairs markers. The HB cross involved flies characterized by an increased cytochrome P-450-dependent bioactivation capacity, which permits the more efficient biotransformation of promutagens and procarcinogens. In both crosses, the wings of the two types of progeny, inversion-free marker heterozygotes and balancer heterozygotes, were analyzed. The results show that IAA and BNOA are not mutagenic or recombinogenic in the wing cells of Drosophila. Furthermore, neither plant growth regulator affected the proliferation rate of HEK293 cells; however, both of them induced cell death at high concentrations.

  10. 吲哚乙酸跨界信号调节植物与细菌互作%Indole-3-acetic Acid-mediated Cross-kingdom Signalling Involved in Plant-bacteria Interactions

    Institute of Scientific and Technical Information of China (English)

    杨扬; 高克祥; 吴岩; 刘晓光

    2016-01-01

    As the most common and naturally-occurring phytohormone of the auxin class,indole-3-acetic acid(IAA)involves in regulating many aspects of plant growth and development. The studies revealed that in nature,not only plant may synthesize the IAA,but also a variety of microorganisms including both phytopathogens and plant growth-promoting bacteria possess the ability of producing the auxin phytohormone inducing plant diseases or promoting plant growth. Interestingly,apart from being the secondary bacterial metabolite interfering the hormone homeostasis of host plants,IAA can also be a signaling molecule modulating gene expression and physiology in bacteria, consequently regulating the plant-bacteria interaction through integration into the complex regulatory network in bacteria. This review provides insights into the recent research progresses on IAA biosynthesis pathways and its regulations in bacteria,IAA-mediated control of bacterial gene expression,physiology and behavior,as well as the interaction with host plants varying from pathogenesis to phytostimulation. The review also highlights that IAA can not only modulate the plant growth,development and defense,but also act as cross-kingdom signal molecules playing a critical role in the regulation of the plant-microbe interactions. The review aims to develop novel strategies for the improvement of the plant-growth promotion and tolerance to both biotic and abiotic stresses by further studying and better understanding of the IAA-mediated cross-kingdom signalling mechanisms and genetically manipulating the bacterial IAA signal pathways.%吲哚-3-乙酸(indole-3-acetic acid,IAA)作为植物体内普遍存在的内源生长素参与调节植物生命活动的诸多方面。研究发现,自然界中不仅植物可以合成 IAA,许多微生物(包括植物病原菌或益生菌)同样具有分泌 IAA 的能力,可以诱发植物病害,或促进植物生长。有趣的是 IAA 不仅作为细菌的次生代

  11. Indole-3-acetic acid (IAA) induced changes in oil content, fatty acid profiles and expression of four fatty acid biosynthetic genes in Chlorella vulgaris at early stationary growth phase.

    Science.gov (United States)

    Jusoh, Malinna; Loh, Saw Hong; Chuah, Tse Seng; Aziz, Ahmad; Cha, Thye San

    2015-03-01

    Microalgae lipids and oils are potential candidates for renewable biodiesel. Many microalgae species accumulate a substantial amount of lipids and oils under environmental stresses. However, low growth rate under these adverse conditions account for the decrease in overall biomass productivity which directly influence the oil yield. This study was undertaken to investigate the effect of exogenously added auxin (indole-3-acetic acid; IAA) on the oil content, fatty acid compositions, and the expression of fatty acid biosynthetic genes in Chlorella vulgaris (UMT-M1). Auxin has been shown to regulate growth and metabolite production of several microalgae. Results showed that oil accumulation was highest on days after treatment (DAT)-2 with enriched levels of palmitic (C16:0) and stearic (C18:0) acids, while the linoleic (C18:2) and α-linolenic (C18:3n3) acids levels were markedly reduced by IAA. The elevated levels of saturated fatty acids (C16:0 and C18:0) were consistent with high expression of the β-ketoacyl ACP synthase I (KAS I) gene, while low expression of omega-6 fatty acid desaturase (ω-6 FAD) gene was consistent with low production of C18:2. However, the increment of stearoyl-ACP desaturase (SAD) gene expression upon IAA induction did not coincide with oleic acid (C18:1) production. The expression of omega-3 fatty acid desaturase (ω-3 FAD) gene showed a positive correlation with the synthesis of PUFA and C18:3n3.

  12. Relationship between Indole-3-Acetic Acid Levels in Apple (Malus pumila Mill) Rootstocks Cultured in Vitro and Adventitious Root Formation in the Presence of Indole-3-Butyric Acid 1

    Science.gov (United States)

    Alvarez, Rafael; Nissen, Scott J.; Sutter, Ellen G.

    1989-01-01

    In vitro rooting response and indole-3-acetic acid (IAA) levels were examined in two genetically related dwarfing apple (Malus pumila Mill) rootstocks. M.26 and M.9 were cultured in vitro using Linsmaier-Skoog medium supplemented with benzyladenine (BA), indole-3-butyric acid (IBA), and 1,3,5-trihydroxybenzoic acid (PG). Rooting response was tested in Lepoivre medium supplemented with IBA and PG. IBA concentrations of 12.0 and 4.0 micromolar induced the maximum rooting percentages for M.9 and M.26, respectively. At these concentrations rooting response was 100% for M.26 and 80% for M.9. Free and conjugated IAA levels were determined in M.26 and M.9 shoots prior to root inducing treatment by high performance liquid chromatography with fluorescence detection and validated by gas chromatography-mass spectrometry using 13[C6]IAA as internal standard. Basal sections of M.26 shoots contained 2.8 times more free IAA than similar tissue in M.9 (477.1 ± 6.5 versus 166.6 ± 6.7 nanograms per gram fresh weight), while free IAA levels in apical sections of M.26 and M.9 shoots were comparable (298.0 ± 4.4 versus 263.7 ± 9.3 nanograms per gram fresh weight). Conjugated IAA levels were significantly higher in M.9 than in M.26 indicating that a greater proportion of total IAA was present as a conjugate in M.9. These data suggest that differences between M.26 and M.9 rooting responses may be related to differences in free IAA levels in the shoot base. PMID:16666562

  13. Preparation of magnetic indole-3-acetic acid imprinted polymer beads with 4-vinylpyridine and β-cyclodextrin as binary monomer via microwave heating initiated polymerization and their application to trace analysis of auxins in plant tissues.

    Science.gov (United States)

    Zhang, Yi; Li, Yuanwen; Hu, Yuling; Li, Gongke; Chen, Yueqin

    2010-11-19

    Auxin is a crucial phytohormone for precise control of growth and development of plants. Due to its low concentration in plant tissues which are rich in interfering substances, the accurate determination of auxins remains a challenge. In this paper, a new strategy for isolation and enrichment of auxins from plant tissues was obtained by the magnetic molecularly imprinted polymer (mag-MIP) beads, which were prepared by microwave heating initiated suspension polymerization using indole-3-acetic acid (IAA) as template. In order to obtain higher selective recognition cavities, an enhanced imprinting method based on binary functional monomers, 4-vinylpyridine (4-VP) and β-cyclodextrin (β-CD), was adopted for IAA imprinting. The morphological and magnetic characteristics of the mag-MIP beads were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy and vibrating sample magnetometry. A majority of resultant beads were within the size range of 80-150μm. Porous surface morphology and good magnetic property were observed. Furthermore, the mag-MIP beads fabricated with 4-VP and β-CD as binary functional monomers exhibited improved recognition ability to IAA, as compared with the mag-MIP beads prepared with the individual monomer separately. Competitive rebinding experiment results revealed that the mag-MIP beads exhibited a higher specific recognition for the template than the non-imprinted polymer (mag-NIP) beads. An extraction method by mag-MIP beads coupled with high performance liquid chromatography (HPLC) was developed for determination of IAA and indole-3-butyric acid (IBA) in plant tissues. Linear ranges for IAA and IBA were in the range of 7.00-100.0μgL(-1) and 10.0-100.0μgL(-1), and the detection limits were 3.9 and 7.4μgL(-1), respectively. The analytical performance was also estimated by seedlings or immature embryos samples from three different plant tissues, pea, rice and wheat. Recoveries were in the range of 70

  14. Preparation and molecular recognition properties of indole-3-acetic acid-imprinted polymers%3-吲哚乙酸印迹聚合物的制备及其分子识别性能

    Institute of Scientific and Technical Information of China (English)

    张铁莉; 刘征原; 张辉; 孟庆朝

    2013-01-01

      以IAA为模板分子,4-乙烯基吡啶(4-Vpy)为功能单体,乙腈为致孔剂,采用本体聚合方法,制备了IAA的印迹聚合物P(4-Vpy),用色谱法评价了其分子识别性能,并且与同样条件下以丙烯酰胺(AA)为功能单体合成的IAA印迹聚合物P(AA)进行了比较。结果表明,乙腈为流动相时,P(4-Vpy)比P(AA)对IAA具有更高的印迹效率,对IAA表现出了更好的分子识别能力。流动相对P(4-Vpy)分子识别能力的影响实验证明,静电作用在其分子识别过程中起重要作用。两种不同用量的乙腈为致孔剂制备所得IAA印迹聚合物P(4-Vpy)和P`(4-Vpy)的色谱测定结果表明,致孔剂的加入量对其印迹效率有显著影响。%In order to synthesize molecular recognition material with high affinity and specificity for indole -3-acetic acid(IAA)and demonstrate the feasibility of such molecular spectrometric methods as UV and fluorometry for the selection of efficient functional monomer,4-vinylpyridine(4-Vpy)-ethyleneglycol dimethacrylate(EGDMA)-based polymers P(4-Vpy)and P`(4-Vpy)were pre-pared by bulk polymerization technique using IAA as the template molecule and two different amounts of acetonitrile as the porogen , respectively.The molecular recognition performances were evaluated by high-performance liquid chromatography.The results exhibi-ted that both of the imprinted polymers showed the ability to recognize IAA and the amount of porogen used in the imprinting process exerted great influence on the imprinting effect.In addition,the comparison of molecular recognition ability was made be-tween P(4-Vpy)and(P(AA))which was prepared under the same condition as P (4-Vpy)except using acrylamide(AA)as the functional monomer.The results indicated that P (4-Vpy) showed higher molecular imprinting efficiency for IAA than P ( AA).The influence of different mobile phase on the retention of IAA and its structurally related

  15. Effects of temperature and gamma radiation on the stability of 125{sub -}19-Iodo cholesterol; Efectos de la temperatura y la radiacion gamma sobre la estabilidad dle 19-Yodocolestero. 125 I

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L.; Rebollo, D. V.; Ruiz, J. M.

    1986-07-01

    He have studied the effect of the temperature and the gamma radiations on the I25I-19-iodocholesterol synthesized in our laboratory; the time of caducity (t 90) have been fixed from the rate constants of decomposition (k) (20,9) 32,1 y 144 . 10-3 h''-1) for different temperatures (35, 50 y 75degree centigree), and the value of Go(-M) (1,52) by radiation of samples of 19-Iodocholesterol-I25 I (0,94 mg/ml) with 60co (0,177 Hrad/h) . (Author) 8 refs.

  16. Identification and characterization of a full-length cDNA encoding for an auxin-induced 1-aminocyclopropane-1-carboxylate synthase from etiolated mung bean hypocotyl segments and expression of its mRNA in response to indole-3-acetic acid.

    Science.gov (United States)

    Botella, J R; Arteca, J M; Schlagnhaufer, C D; Arteca, R N; Phillips, A T

    1992-11-01

    1-Aminocyclopropane-1-carboxylate (ACC) synthase (EC 4.4.1.14) is the key regulatory enzyme in the ethylene biosynthetic pathway. The identification and characterization of a full-length cDNA (pAIM-1) 1941 bp in length for indole-3-acetic acid (IAA)-induced ACC synthase is described in this paper. The pAIM-1 clone has an 87 bp leader and a 402 bp trailing sequence. The open reading frame is 1452 bp long encoding for a 54.6 kDa polypeptide (484 amino acids) which has a calculated isoelectric point of 6.0. In vitro transcription and translation experiments support the calculated molecular weight and show that the enzyme does not undergo processing. Eleven of the twelve amino acid residues which are conserved in aminotransferases are found in pAIM-1. The sequence for pMAC-1 which is one of the 5 genes we have identified in mung bean is contained in pAIM-1. pAIM-1 shares between 52 to 65% homology with previously reported sequences for ACC synthase at the protein level. There is little detectable pAIM-1 message found in untreated mung bean tissues; however, expression is apparent within 30 min following the addition of 10 microM IAA reaching a peak after approximately 5 h with a slight decrease in message after 12 h. These changes in message correlate with changes in ACC levels found in these tissues following treatment with 10 microM IAA.

  17. Comparative study of visual inspection of the cervix by 3% acetic acid (VIA versus Pap smear by Bethesda method in sexually active women aged 25-50 years as an equally or more effective cervical cancer screening method in a low resource setup

    Directory of Open Access Journals (Sweden)

    Mohit Rajendra Saraogi

    2014-06-01

    Full Text Available Background: Cervical cancer is the most common cancer in Indian women and is a preventable cancer. Pap smear being an expensive screening test, increased emphasis is being laid on the development of a reliable and cost effective screening method for cervical cancer. This study aims at early detection of cervical dysplastic lesions using a simple and cost-effective screening test like visual inspection of cervix with 3% acetic acid (VIA and comparing its diagnostic efficacy with the more expensive Pap screening by Bethesda method. Methods: Ours was a prospective study carried out on a 100 sexually active women aged 25-50 years, coming to our OPD. The women were subjected to both a VIA and Pap smear. All Pap and VIA positive women were subjected to a cervical biopsy, whose histopathological report was taken as the gold standard. Results: In our study the sensitivity of VIA was more than that of cytology (100% versus 66.67% but the specificity was significantly lesser (47.83% compared to the 73.91%. The negative predictive value of VIA was comparable with Pap smear (100% and 85% respectively as was the positive predictive value (42.86% and 50%. However the diagnostic accuracy of VIA was lower than that of Pap smear (66.67% and 81.25% in our study. Conclusions: In this study VIA was found to have efficacy comparable to Pap smear in screening cervical cancer. Thus we recommend that VIA could be used as an alternative screening tool to detect early cervical dysplasia - especially in poor resource settings. [Int J Reprod Contracept Obstet Gynecol 2014; 3(3.000: 688-691

  18. 含噻唑烷二酮-3-乙酸结构查尔酮衍生物的合成及抗菌活性的研究%Synthesis and Anti-bacterial Activity of Novel Chalcone Derivatives Containing 2,4-Thiazolidinedione-3-acetic Acid Moiety

    Institute of Scientific and Technical Information of China (English)

    孟凡领; 郑昌吉; 李因晶; 孙良鹏; 刘学坤; 张天一; 朴虎日

    2012-01-01

    A series of novel chalcone derivatives bearing the 2,4-thiazolidinedione-3-acetic acid moieties (8a~8p) were synthesized, and evaluated for their anti-bacterial activity. The results demonstrated that some compounds presented good antimicrobial activities against four multidrug-resistant clinical isolates, among which compounds 8g, 8i, 81 and 8m with minimum inhibitory concentration (MIC) value of 4 ug/mL showed as active as the standard drug, norfloxacin, against methi-cillin-resistant S. Aureus. None of the compounds exhibited obvious activity against the Gram-negative bacteria E. Coli 1356 at 64 μg/mL.%合成了一系列含噻唑烷二酮-3-乙酸结构的新型查尔酮衍生物,并对化合物进行了抗菌活性测定.结果显示,一些化合物对4种多重耐药菌显示出较强的抗菌活性,其中化合物8g,8i,8l和8m在抗耐甲氧西林金黄色葡萄球菌的最小抑制浓度(MIC)达到4 μg/mL,与对照药诺氟沙星(norfloxacin)相当.另外,在64 μg/mL浓度下,所有化合物对大肠杆菌1356均无明显抑制活性.

  19. Endogenous Quantification of Abscisic Acid and Indole-3-Acetic Acid in Somatic and Zigotic Embryos of Nothofagus alpina (Poepp. & Endl. Oerst Cuantificación Endógena de Ácido Abscísico y Ácido Indol-3 Acético en Embriones Somáticos y Cigóticos de Nothofagus alpina (Poepp. & Endl. Oerst

    Directory of Open Access Journals (Sweden)

    Pricila Cartes Riquelme

    2011-12-01

    Full Text Available Abscisic acid (ABA and indole-3-acetic acid (IAA participate in the propagation of plants by somatic embryogenesis, causing polar structural differentiation of the embryo. The goal of the assay was to compare endogenous levels of ABA and IAA between somatic embryos (SE and zygotic embryos (ZE of Nothofagus alpina (Poepp. & Endl. Oerst. In this study, a somatic embryo maturation assay involving the addition of varying concentrations of exogenous ABA was performed on cotyledonary-stage of N. alpina. Furthermore, the endogenous levels of ABA and IAA were quantified in the immature ZE, the mature ZE, and the embryonic axis of a mature embryo of N. alpina. The current study utilized high performance liquid chromatography (HPLC for quantification. The maturation treatments performed did not present significant differences in the endogenous ABA levels in SE. However, significant differences did exist in levels of ABA and IAA between SE submitted to the different maturation treatments and mature ZE of N. alpina. The application of exogenous ABA to the culture medium increased endogenous ABA levels, therefore, increasing the number of germinated somatic embryos. Thus, the plant conversion process was also successfully completed in somatic embryos of N. alpina.El ácido abscísico (ABA y el ácido indol 3 acético (IAA participan en el proceso de propagación de plantas mediante embriogénesis somática, ya que permiten la diferenciación de la estructura polar del embrión, órganos y regiones meristemáticas de éste. En este estudio se llevó a cabo un ensayo de maduración de embriones somáticos en estado cotiledonar con la adición de diferentes concentraciones de ABA exógeno, además se determinaron niveles endógenos entre ZE inmaduro, ZE maduro, y eje embrionario aislado desde el embrión maduro para luego comparar niveles endógenos de ABA e IAA en embriones somáticos (SE y cigóticos (ZE de raulí, Nothofagus alpina (Poepp. & Endl. Oerst. La

  20. Migração de β-caprolactama de embalagens contendo poliamida 6 para simulante ácido acético 3% e validação do método analítico β-Caprolactam migration from polyamide 6 packaging into 3% acetic acid food simulant and validation of the analytical method

    Directory of Open Access Journals (Sweden)

    Juliana Silva Félix

    2007-08-01

    Full Text Available Este trabalho teve como objetivo desenvolver e validar método analítico para determinar ε-caprolactama no simulante de alimentos solução de ácido acético 3% e estudar sua migração de embalagens contendo poliamida 6 para o simulante em contato. Foi empregada a cromatografia gasosa usando ε-caprolactama como padrão analítico e 2-azociclononanona como padrão interno. A linearidade esteve entre 1,60 e 640,00 µg de ε-caprolactama.mL-1 de simulante, com coeficiente de correlação 0,9999. Os limites de detecção e de quantificação do método foram 0,24 e 1,60 ng, respectivamente. A precisão do método revelou valores de coeficiente de variação menores que 4,3% e a avaliação da exatidão mostrou recuperação de 100 a 106%. O método demonstrou ser eficaz para quantificar ε-caprolactama no simulante, apresentando ampla linearidade, boa precisão e exatidão. No ensaio de migração, embalagens contendo poliamida 6 foram colocadas em tubos de vidro com 10 mL do simulante, que foram hermeticamente fechados e acondicionados a 40 ± 1 °C durante 10 dias. O ensaio de migração foi realizado por imersão total. A quantidade de ε-caprolactama migrada variou de 7,8 a 10,5 e de 6,9 a 7,6 mg.kg-1 de simulante para as embalagens destinadas aos produtos cárneos e queijos, respectivamente. Todas as embalagens atenderam às exigências da Legislação Brasileira para migração de ε-caprolactama.The aim of this work was to develop and validate an analytical method to determine ε-caprolactam in 3% acetic acid solution and to study its migration from polyamide 6 into food simulant. Gas chromatography was used with ε-caprolactam as an analytical standard and 2-azacyclononanone as an internal standard. The linearity was obtained by the concentration range of 1.60 to 640.00 µg.mL-1, with a correlation coefficient of 0.9999. Detection and quantification limits of the method were 0.24 ng and 1.60 ng, respectively. Relative standard

  1. Oxygen-dependent catabolism of indole-3-acetic acid in Bradyrhizobium japonicum

    DEFF Research Database (Denmark)

    Egebo, L A; Nielsen, S V; Jochimsen, B U

    1991-01-01

    addition of the substrates for induction and is oxygen dependent. The highest activity is obtained when the concentration of inducer is 0.2 mM. Spectrophotometric data are consistent with the suggestion that the indole ring is broken during degradation of IAA. We hypothesize that the enzyme catalyzes...

  2. Distinct Characteristics of Indole-3-Acetic Acid and Phenylacetic Acid, Two Common Auxins in Plants

    Science.gov (United States)

    Sugawara, Satoko; Mashiguchi, Kiyoshi; Tanaka, Keita; Hishiyama, Shojiro; Sakai, Tatsuya; Hanada, Kousuke; Kinoshita-Tsujimura, Kaori; Yu, Hong; Dai, Xinhua; Takebayashi, Yumiko; Takeda-Kamiya, Noriko; Kakimoto, Tatsuo; Kawaide, Hiroshi; Natsume, Masahiro; Estelle, Mark; Zhao, Yunde; Hayashi, Ken-ichiro; Kamiya, Yuji; Kasahara, Hiroyuki

    2015-01-01

    The phytohormone auxin plays a central role in many aspects of plant growth and development. IAA is the most studied natural auxin that possesses the property of polar transport in plants. Phenylacetic acid (PAA) has also been recognized as a natural auxin for >40 years, but its role in plant growth and development remains unclear. In this study, we show that IAA and PAA have overlapping regulatory roles but distinct transport characteristics as auxins in plants. PAA is widely distributed in vascular and non-vascular plants. Although the biological activities of PAA are lower than those of IAA, the endogenous levels of PAA are much higher than those of IAA in various plant tissues in Arabidopsis. PAA and IAA can regulate the same set of auxin-responsive genes through the TIR1/AFB pathway in Arabidopsis. IAA actively forms concentration gradients in maize coleoptiles in response to gravitropic stimulation, whereas PAA does not, indicating that PAA is not actively transported in a polar manner. The induction of the YUCCA (YUC) genes increases PAA metabolite levels in Arabidopsis, indicating that YUC flavin-containing monooxygenases may play a role in PAA biosynthesis. Our results provide new insights into the regulation of plant growth and development by different types of auxins. PMID:26076971

  3. Distinct Characteristics of Indole-3-Acetic Acid and Phenylacetic Acid, Two Common Auxins in Plants.

    Science.gov (United States)

    Sugawara, Satoko; Mashiguchi, Kiyoshi; Tanaka, Keita; Hishiyama, Shojiro; Sakai, Tatsuya; Hanada, Kousuke; Kinoshita-Tsujimura, Kaori; Yu, Hong; Dai, Xinhua; Takebayashi, Yumiko; Takeda-Kamiya, Noriko; Kakimoto, Tatsuo; Kawaide, Hiroshi; Natsume, Masahiro; Estelle, Mark; Zhao, Yunde; Hayashi, Ken-Ichiro; Kamiya, Yuji; Kasahara, Hiroyuki

    2015-08-01

    The phytohormone auxin plays a central role in many aspects of plant growth and development. IAA is the most studied natural auxin that possesses the property of polar transport in plants. Phenylacetic acid (PAA) has also been recognized as a natural auxin for >40 years, but its role in plant growth and development remains unclear. In this study, we show that IAA and PAA have overlapping regulatory roles but distinct transport characteristics as auxins in plants. PAA is widely distributed in vascular and non-vascular plants. Although the biological activities of PAA are lower than those of IAA, the endogenous levels of PAA are much higher than those of IAA in various plant tissues in Arabidopsis. PAA and IAA can regulate the same set of auxin-responsive genes through the TIR1/AFB pathway in Arabidopsis. IAA actively forms concentration gradients in maize coleoptiles in response to gravitropic stimulation, whereas PAA does not, indicating that PAA is not actively transported in a polar manner. The induction of the YUCCA (YUC) genes increases PAA metabolite levels in Arabidopsis, indicating that YUC flavin-containing monooxygenases may play a role in PAA biosynthesis. Our results provide new insights into the regulation of plant growth and development by different types of auxins. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

  4. Dynamics of indole-3-acetic acid oxidase activity in suspension culture of sunflower crown-gall

    Directory of Open Access Journals (Sweden)

    Zofia Chirek

    2014-02-01

    Full Text Available IAA oxidase activity was determined in several growth phases of a suspension culture of sunflower crown-gall. During the short phase of intensive growth (zero passage - PO a negative correlation was noted between enzymatic activity and the rate of growth. IAA oxidase activity increased to a certain level is not a factor limiting cell division. For protraction of the phase of intensive growth (first passage - P1, however, a decrease in the activity of this enzyme seems indispensable. IAA oxidase activity in the tested culture is under the control of inhibitors present in the cells and medium. High enzyme inhibition was observed in PO cells during the phase, of intensive growth and in P1 at the beginning and in the middle part of this phase. These results suggest' that the -auxin level determined in earlier studies in sunflower crown-gall culture is controlled by the IAA oxidase set. During the long phase of intensive growth (P1 this control is of negative feedback type.

  5. The transport of indole-3-acetic Acid in boron- and calcium-deficient sunflower hypocotyl segments.

    Science.gov (United States)

    Tang, P M; Dela Fuente, R K

    1986-06-01

    Transfer of sunflower (Helianthus annuus L. cv Russian Mammoth) seedlings from complete nutrient solution to solutions deficient in either boron or calcium resulted in a steady decline in the rate of auxin transport, compared to seedlings that remained in the complete solution. In seedlings transferred to solutions deficient in both B and Ca, the decline in auxin transport was greater than seedlings deficient in only one element. The transfer of B- or Ca-deficient seedlings back to the complete solution prevented further decline in auxin transport, but auxin transport did not increase to the same level as seedlings maintained in complete solution. The significant reduction in auxin transport during the early stages of B or Ca deficiency was not related to (a) reduced growth rate of the hypocotyl, (b) increased acropetal movement of auxin, or (c) lack of respiratory substrates in the hypocotyl. In addition, no difference was found in the water-extractable total and ionic Ca in B-deficient and control nondeficient hypocotyls, indicating a direct effect of B on auxin transport, rather than indirectly by affecting Ca absorption. The rate of auxin transport in hypocotyls deficient in either B or Ca, was inversely correlated with K(+) leakage and rate of respiration. The data presented strongly support the view that there are separate sites for B and Ca in the basipetal transport of the plant hormone indoleacetic acid.

  6. Effect of indole-3-acetic acid on pea root growth, peroxidase profiles and hydroxyl radical formation

    Directory of Open Access Journals (Sweden)

    Kukavica Biljana

    2007-01-01

    Full Text Available Changes in growth, peroxidase profiles, and hydroxyl radical formation were examined in IAA (0.5-10 mg/l treated pea plants grown hydroponically and in isolated roots in liquid in vitro culture. IAA inhibited root elongation, both in hydroponically grown pea plants and in isolated roots in vitro. A remarkable increase in the number of POD iso­forms was noticed in isolated roots grown in vitro, compared to the roots from plants grown hydroponically. IAA induced both disappearance of several root POD isoforms and hydroxyl radical formation in the root and the root cell wall.

  7. Changes in Growth, Auxin- and Ribonucleic Acid Metabolism in Wheat Coleoptile Sections Following Pulse Treatment with Indole-3-Acetic Acid

    DEFF Research Database (Denmark)

    Truelsen, T.A.; Galston, A.W.

    1966-01-01

    after the pretreatment showed that the attered growth patterns could be ascribed to declining auxin content with time, but not to thc actual concentration in the sections. The results indicate that the metabolic activation brought about by IAA leads to its own disappearance. Such a phenomenon...

  8. On the role of calcium in indole-3-acetic acid movement and graviresponse in etiolated pea epicotyls

    Science.gov (United States)

    Migliaccio, F.; Galston, A. W.

    1989-01-01

    To determine whether Ca2+ plays a special role in the early graviresponse of shoots, as has been reported for roots, we treated etiolated pea epicotyls with substances known to antagonize Ca2+ (La3+), to remove Ca2+ from the wall (spermidine, EGTA), to inhibit calmodulin mediated reactions (chlorpromazine), or to inhibit IAA transport (TIBA). We studied the effect of these substances on IAA and Ca2+ uptake into 7 mm long subapical 3rd internode etiolated pea epicotyl sections and pea leaf protoplasts, on pea epicotyl growth, and graviresponse and on lateral IAA redistribution during gravistimulation. Our results support the view that adequate Ca2+ in the apoplast is required for normal IAA uptake, transport and graviresponse. Experiments with protoplasts indicate that Ca2+ may be controlling a labile membrane porter, possibly located on the external surface of cell membrane, while inhibitor experiments suggest that calmodulin is also implicated in both the movement of IAA and graviresponse. Since a major transfer of Ca2+ through free space during graviresponse has not yet been demonstrated, and since inhibition of calcium channels does not affect IAA redistribution (Migliaccio and Galston, 1987, Plant Physiology 85:542), we conclude that no clear evidence links prior Ca2+ movement with IAA redistribution during graviresponse in stems.

  9. Sulfur nutrient availability regulates root elongation by affecting root indole-3-acetic acid levels and the stem cell niche

    Institute of Scientific and Technical Information of China (English)

    Qing Zhao; Yu Wu; Lei Gao; Jun Ma; Chuan-You Li; Cheng-Bin Xiang

    2014-01-01

    Sulfur is an essential macronutrient for plants with numerous biological functions. However, the influence of sulfur nutrient availability on the regulation of root development remains largely unknown. Here, we report the response of Arabidopsis thaliana L. root development and growth to different levels of sulfate, demonstrating that low sulfate levels promote the primary root elongation. By using various reporter lines, we examined in vivo IAA level and distribution, cel division, and root meristem in response to different sulfate levels. Meanwhile the dynamic changes of in vivo cysteine, glutathione, and IAA levels were measured. Root cysteine, glutathione, and IAA levels are positively correlated with external sulfate levels in the physiological range, which eventual y affect root system architecture. Low sulfate levels also downregulate the genes involved in auxin biosynthesis and transport, and elevate the accumulation of PLT1 and PLT2. This study suggests that sulfate level affects the primary root elongation by regulating the endogenous auxin level and root stem cel niche maintenance.

  10. Interaction indole-3-acetic acid IAA with lectin Canavalia maritima seeds reveal new function of lectins in plant physiology

    Energy Technology Data Exchange (ETDEWEB)

    Silva Filho, J.C.; Santi-Gadelha, T.; Gadelha, C.A.A.; Delatorre, P. [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Teixeira, C.S.; Rocha, B.A.M.; Nobrega, R.B.; Alencar, K.L.L.; Cavada, B.S. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil)

    2012-07-01

    Full text: Lectins are a class of proteins of non-immune origin characterized by its capability in interacts specifically and reversibly to mono and oligosaccharides. In plant several possible roles have been suggested including their function in seed maturation, cell wall assembly, defense mechanisms, or rhizobial nodulation of legume roots. Nearly all application and proposed of the plant lectins are based on their specific carbohydrate binding. However, it has been reported that lectins from legumes, might interact with other molecules, such as non proteic amino acids and hydrophobic compounds. This study show the first the crystal structure based on molecular replacement of the Canavalia maritima (CML) complexed with IAA correlated with possible role in plant development. Purified CML was dissolved in 20 mMTrisHCl pH 7.6 containing 5 mM IAA, the suitable co-crystals from CML-IAA complex grew in condition 4 of screen I (0.1 M TrisHCl pH 8.5 and 2.0 M ammonium sulfate). This crystal belong to the orthorhombic space group I222 with unit-cell parameters a = 67.1 ; b = 70.7 , c = 97.7 , The structure was refined at 2.1 of resolution to a final R factor of 20.63 % and an R free of 22.54 %. To check the relative position of the IAA molecule in relation to the biological assemble of the CML, the tetrameric structure was generate by crystallographic symmetry. IAA molecules are positioned in the central cavity. The IAA is stabilized by interacting through hydrogen bounds and Van der Waals forces with the amino acids residues Ser 108 and Asn131, and two water molecules. The hydrophilic interactions occur between IAA and side chains of Ser 108, Asn131 and water molecules 26 and 31 by H-bonds. The OG oxygen from Ser108 display H-bonds with O2 and O3 oxygen atoms from IAA, 3.1 and 2.8 respectively. The tetrameric structure of CML complexed with IAA revels which this protein can act during the seedling in plant development. (author)

  11. Activity of indolyl-3-acetic acid oxidase and peroxidase in roots of carrot infested with Meloidogyne hapla Chiuu.

    Directory of Open Access Journals (Sweden)

    Krystyna M. Janas

    2015-06-01

    Full Text Available IAA-oxidase and peroxidase activity was measured in storage and side roots of healthy and M. hapla infested carrots of two sultivars. Cultivar 'Perfekcja' is sensitive whereas cv. 'Slendero' is tolerant to the northern root-knot ne-matode. 3-, 4-, and 5-month-old plants were subjected to analyses. In M. hapla infested plants of both cultivars IAA-oxidase inhibitors accumulated. Kinetics of IAA oxidation in vivo were the same in healthy and infested plants. IAA-oxidase activity in vitro was inhibited in crude extracts of the infested tissues, the inhibition being prevented by PVP. Peroxidase activity increased in secondary phloem and decreased in galled side roots of both cultivars when compared with healthy controls. In galled side roots of the youngest 3-month-old plants peroxidase activity was not decreased. IAA-oxidase inhibitors accumulated in the infested roots.It is concluded that M. hapla has no direct effect on IAA-oxidase. Degree of tolerance to nematodes is correlated with the ratio of IAA-oxidase inhibitors to IAA-oxidase rather than with the absolute activity of IAA-oxidase.

  12. Sulfur nutrient availability regulates root elongation by affecting root indole-3-acetic acid levels and the stem cell niche.

    Science.gov (United States)

    Zhao, Qing; Wu, Yu; Gao, Lei; Ma, Jun; Li, Chuan-You; Xiang, Cheng-Bin

    2014-12-01

    Sulfur is an essential macronutrient for plants with numerous biological functions. However, the influence of sulfur nutrient availability on the regulation of root development remains largely unknown. Here, we report the response of Arabidopsis thaliana L. root development and growth to different levels of sulfate, demonstrating that low sulfate levels promote the primary root elongation. By using various reporter lines, we examined in vivo IAA level and distribution, cell division, and root meristem in response to different sulfate levels. Meanwhile the dynamic changes of in vivo cysteine, glutathione, and IAA levels were measured. Root cysteine, glutathione, and IAA levels are positively correlated with external sulfate levels in the physiological range, which eventually affect root system architecture. Low sulfate levels also downregulate the genes involved in auxin biosynthesis and transport, and elevate the accumulation of PLT1 and PLT2. This study suggests that sulfate level affects the primary root elongation by regulating the endogenous auxin level and root stem cell niche maintenance. © 2014 Institute of Botany, Chinese Academy of Sciences.

  13. Accumulation of intra-cellular polyphosphate in Chlorella vulgaris cells is related to indole-3-acetic acid produced by Azospirillum brasilense.

    Science.gov (United States)

    Meza, Beatriz; de-Bashan, Luz E; Hernandez, Juan-Pablo; Bashan, Yoav

    2015-06-01

    Accumulation of intra-cellular phosphate, as polyphosphate, was measured when the microalga Chlorella vulgaris was immobilized in alginate with either of two wild-type strains of the microalgae growth-promoting bacterium Azospirillum brasilense or their corresponding IAA-attenuated mutants. Wild type strains of A. brasilense induced higher amounts of intra-cellular phosphate in Chlorella than their respective mutants. Calculations comparing intra-cellular phosphate accumulation by culture or net accumulation by the cell and the amount of IAA that was produced by each of these strains revealed that higher IAA was linked to higher accumulations of intra-cellular phosphate. Application of four levels of exogenous IAA reported for A. brasilense and their IAA-attenuated mutants to cultures of C. vulgaris enhanced accumulation of intra-cellular phosphate; the higher the content of IAA per culture or per single cell, the higher was the amount of accumulated phosphate. When an IAA-attenuated mutant was complemented with exogenous IAA, accumulation of intra-cellular phosphate at the culture level was even higher than phosphate accumulation with the respective wild type strains. When calculating the net accumulation of intra-cellular phosphate in the complementation experiment, net intra-cellular phosphate induced by the IAA-attenuated mutant was completely restored and was similar to the wild strains. We propose that IAA produced by A. brasilense is linked to polyphosphate accumulation in C. vulgaris.

  14. The acropetal effects of indole-3-acetic acid in isolated shoot segments of Acer pseudoplatanus L. II. Possible regulation by a vectorial fieid of auxin waves

    Directory of Open Access Journals (Sweden)

    Jacek A. Adamczyk

    2014-02-01

    Full Text Available The acropetal effects of auxin on elongation of axillary buds and on modulation of the wave-like pattern of basipetal efflux of natural auxin to agar from Acer pseudoplatanus L. shoots were studied. When synthetic IAA was applied to cut surfaces of one of two branches the elongation growth of buds situated on the opposite branch was retarded, suggesting regulation independent of the direct action of the molecules of the applied IAA. Oscillations in basipetal transport of natural auxin along the stem segments were observed corroborating the results of other authors using different tree species. Apical application of synthetic IAA for 1 hour to the lateral branch caused a phase shift of the wave-like pattern of basipetal efflux of natural auxin, when the stem segment above the treated branch was sectioned. The same effect was observed evoked by the laterally growing branch which is interpreted as an effect of natural auxin produced by the actively growing shoot. These modulations could be propagated acropetally at a rate excluding direct action of auxin molecules at the sites of measurement. The results seem to corroborate the hypothesis suggesting that auxin is involved in acropetal regulation of shoot apex growth through its effect upon modulation of the vectorial field which arises when the auxin-waves translocate in cambium.

  15. Role of non enzymatic synthesis of indole-3-acetic acid in the Ipomoea batatas L. Lam. (sweet potato) response to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lage, C.L.S.; Esquibel, M.A. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Biofisica. Lab. de Fisiologia Vegetal

    1995-12-01

    Indolacetic acid (IAA) production by tryptophan radiolysis was evaluated after irradiation of a tryptophan solution (1.0 mg/ml) with a 2000 Gy dose of gamma rays followed by High Performance Liquid Chromatography (HPLC) analysis. New absorbance peaks at 280 nm were detected in the irradiated solution, one of them having a migration time similar to that of IAA, indicating a0.14% yield for the conversion reaction. The low yield led us to abandon the hypothesis that non-enzymatic IAA synthesis may account for growth simulation. When the electrophoretic patterns of peroxidases from absorbent roots derived from storage roots treated with IAA (1.0 mg/l) or gamma radiation were compared with control, differences were detected only in the irradiated material. Thus the growth radiation-induced effects do not seem to result from a sudden endogenous IAA increment. (author)

  16. Polyphenols and inhibitors of indoIyl-3-acetic acid oxidase in carrot roots infested with northern root-knot nematode

    Directory of Open Access Journals (Sweden)

    Krystyna M. Janas

    2015-06-01

    Full Text Available It is suggested that IAA-oxidase inhibitors accumulate in plants infested by the nematodes. This leads to local accumulation of active auxins and causes proliferation of tissues near the place of nematode infection. T e carrot cv. Slendero seems to be less sensitive to nematode as the inhibitors of IAA-oxidase do not accumulate at early stages of infection.

  17. Both free indole-3-acetic acid and the photosynthetic performance are important players in the response of Medicago truncatula to urea and ammonium nutrition under axenic conditions

    Directory of Open Access Journals (Sweden)

    RAQUEL eEsteban

    2016-02-01

    Full Text Available We aimed to identify the early stress response and plant performance of Medicago truncatula growing in axenic medium with ammonium or urea as the sole source of nitrogen with respect to nitrate based nutrition through biomass measurements, auxin contents analyses, root system architecture response analyses, and physiological determinations. Both ammonium and ureic nutrition severely affected the root system architecture, resulting in changes in the main elongation rate, lateral root development and insert position from the base. The auxin content decreased in both urea- and ammonium- treated roots; however, only the ammonium- treated plants were affected at the shoot level. The analysis of chlorophyll a fluorescence transients showed that ammonium affected photosystem II, but urea did not impair photosynthetic activity. Superoxide dismutase isoenzymes in the plastids were moderately affected by urea and ammonium in the roots. Overall, our results showed that low N doses from different sources had no remarkable effects on M. truncatula, with the exception of the differential phenotypic root response. High dose of both ammonium and urea caused great changes at plant length, auxin content and physiological determinations. The interesting correlations found between the shoot auxin pool, the plant length, and the parameter performance index, obtained from the chlorophyll a fluorescence rise kinetics measurements, indicated that both IAA pool and performance index are an important part of the response of M. truncatula under ammonium or urea as a sole N source.

  18. Callus induction of leaf explant Piper betle L. Var Nigra with combination of plant growth regulators indole-3-acetic acid (IAA), benzyl amino purin (BAP) and kinetin

    Science.gov (United States)

    Junairiah, Zuraidassanaaz, Nabilah Istighfari; Izdihar, Fairuz Nabil; Manuhara, Yosephine Sri Wulan

    2017-09-01

    The purpose of this research was to determine the combination of plant growth regulators IAA, BAP and kinetin towards callus induction and growth of leaf explants Piper betle L. VarNigra. Explants from leaf of Piper betle L. VarNigra was cultured on MS medium with 24 treatment combinations of plant growth regulators IAA and BAP and 24 treatment combinations of plant growth regulators IAA and kinetin with 0.0;0.5;1.0;1.5;2.0 mg/L concentration respectively, the observed variable were the length of time the formation of callus, callus morphology, fresh and dry weight of callus. The results of this research showed that the combination of growth regulators IAA with BAP and kinetin had effects on leaf growth of Piper betle L. VarNigra. During 8 weeks observation, it indicated that the combination of concentration IAA 0.5 mg/L and BAP 2.0 mg/L showed fastest callus formation at 8.5 days. Combination of concentration IAA 1.0 mg/L and BAP 1.5 mg/L showed the highest of fresh weight at 0.6596 grams, and the highest dry weight was obtained from the combination of concentration IAA 0.5 mg/L and BAP 0.5 mg/L at 0.0727 grams. Combination of concentration IAA 1.0 mg/L and kinetin 1.5 mg/L had the highest of fresh weight at 0.2972 grams and the highest dry weight at 0.1660 grams. Callus of Piper betle L. VarNigra had two textures, that were compact and friable, and also showed various kind of colors, like white, greenish white, yellowish white, tanned white, brown and black. Based on this research, that concentration IAA 1.0 mg/L and 1.5 mg/L kinetin was the best combination for induction of callus from leaf of Piper betle L. Var Nigra.

  19. Effects of Indole-3-acetic Acid on the Growth and Lipid-Producing Capacity of Chlorella vulgaris XJB%三吲哚乙酸对Chlorella vulgaris XJB生长及产油能力的影响

    Institute of Scientific and Technical Information of China (English)

    王思雨; 徐小琳; 贺莹莹; 代斌; 李春; 王长海

    2013-01-01

    三吲哚乙酸(IAA)具有促进细胞增殖的作用,将其添加到培养基中能够提升藻类细胞生长,可增强利用微藻发展生物柴油的能力.本文以自行筛选到的一株具有快速生长能力的微藻Chlorella vulgaris XJB为研究对象,考察了IAA添加时间和添加浓度对C.vulgaris XJB生长及产油能力的影响.实验研究结果表明,在微藻生长适应期,添加适宜浓度的IAA有助于藻体生物量的累积和油脂产率的提高,但对油脂含量的影响较小,当第0天添加0.08 mg/L IAA时,细胞个数、生物量及油脂产率达到最大值,分别为20.2×106个/mL、338.9 mg/L、15.2 mg/(L/d),油脂含量为22.4%,此时生物量和油脂产率分别是未经IAA处理条件下的2.5倍和2.0倍.

  20. Cleavage of INDOLE-3-ACETIC ACID INDUCIBLE28 mRNA by microRNA847 upregulates auxin signaling to modulate cell proliferation and lateral organ growth in Arabidopsis.

    Science.gov (United States)

    Wang, Jing-Jing; Guo, Hui-Shan

    2015-03-01

    MicroRNAs function in a range of developmental processes. Here, we demonstrate that miR847 targets the mRNA of the auxin/indole acetic acid (Aux/IAA) repressor-encoding gene IAA28 for cleavage. The rapidly increased accumulation of miR847 in Arabidopsis thaliana coincided with reduced IAA28 mRNA levels upon auxin treatment. This induction of miR847 by auxin was abolished in auxin receptor tir1-1 and auxin-resistant axr1-3 mutants. Further analysis demonstrates that miR847 functions as a positive regulator of auxin-mediated lateral organ development by cleaving IAA28 mRNA. Importantly, the ectopic expression of miR847 increases the expression of cell cycle genes as well as the neoplastic activity of leaf cells, prolonging later-stage rosette leaf growth and producing leaves with serrated margins. Moreover, both miR847 and IAA28 mRNAs are specifically expressed in marginal meristems of rosette leaves and lateral root initiation sites. Our data indicate that auxin-dependent induction of miR847 positively regulates meristematic competence by clearing IAA28 mRNA to upregulate auxin signaling, thereby determining the duration of cell proliferation and lateral organ growth in Arabidopsis. IAA28 mRNA encodes an Aux/IAA repressor protein, which is degraded through the proteasome in response to auxin. Altered signal sensitization to IAA28 mRNA levels, together with targeted IAA28 degradation, ensures a robust signal derepression.

  1. Chronic subarachnoid administration of 1-(4chlorobenzoyl)-5methoxy-2methyl-1H-indole-3 acetic acid (indomethacin): an evaluation of its neurotoxic effects in an animal model.

    Science.gov (United States)

    Guevara-López, Uriah; Covarrubias-Gómez, Alfredo; Gutierrez-Acar, Hilario; Aldrete, J Antonio; López-Muñoz, Francisco J; Martínez-Benítez, Braulio

    2006-07-01

    Neuraxial administration of nonsteroid antiinflammatory drugs has been suggested as an alternative in the management of intractable pain, but there is little evidence that the neurotoxic effects of indomethacin by this route of administration have been evaluated. In this study, we evaluated histological neurotoxicity of indomethacin after its subarachnoid administration in guinea pigs. The hypothesis tested was "Does subarachnoid administration of indomethacin produce damage in the spinal cord of guinea pigs?" Ten male guinea pigs were anesthetized, and a polyamide catheter connected to a subcutaneous osmotic micro-pump was implanted at the L2-3 level. Animals were randomly assigned in 2 groups of 5 animals each. Indomethacin or saline solution was administered by continuous infusion (0.5 microL/h) for 14 days. Neurotoxicity was determined by spinal cord histopathology. There was no evidence of toxicity in the histological examinations of either group. These data suggest that subarachnoid administration of indomethacin infusion, at these doses, did not produce lesions typical of neurotoxicity in the spinal cord. We have concluded that epidural administration of indomethacin may be considered an alternative for application in human pain management, although more studies to determine its safety are required.

  2. Investigations of the metabolism of the hormones ethylen, abscisic acid and indol-3-acetic acid in coniferous trees in forest die-back areas of south western Germany; Untersuchungen zum Haushalt der Hormone Ethylen, Abscisinsaeure und Indol-3-essigsaeure in Nadelbaeumen aus Waldschadensgebieten Suedwestdeutschlands

    Energy Technology Data Exchange (ETDEWEB)

    Christmann, A.

    1993-12-31

    The author investigated changes in the hormone metabolism of affected trees; he intended to analyze as many hormones as possible. The investigations were carried out on needles, owing to the fact that the symptoms observed suggested specific disturbances of the needle hormone metabolism. Further, needles are the main point of attack of airborne pollutants. In physiologically healthy trees, the seasonal changes in hormone levels were investigated as a function of different parameters such as forest site, needle age, tree age, and position of sample branches in the tree crown. On this basis, hormone changes resulting from tree disease were characterized for the sample trees. SO{sub 2} and ozone were taken into account in the investigations. It was found that although the development with time of physiological and structural characteristics suggests premature aging of the needles of affected trees, the changes in the hormone metabolism do not correspond to the hormonal control patterns of natural needle aging. SO-2 exposure or a lack of minerals at the forest site are excluded as causes of the observed damage. No conclusive information could be obtained on the effects of ozone. (orig./MG) [Deutsch] Es war ein Ziel dieser Arbeit, nachzuweisen, welche Veraenderungen im Hormonhaushalt erkrankter Baeume vorliegen und dabei moeglichst viele Hormone zu bearbeiten. Die Untersuchungen wurden an Nadeln durchgefuehrt, da die beobachtbaren Symptome fuer eine Stoerung des Hormonhaushaltes vor allem dieser Organe sprachen und sie zudem Hauptangriffsort fuer Luftschadstoffe sind. An physiologisch gesunden Baeumen wurde das Verhalten der einzelnen Hormone im Jahresverlauf in Abhaengigkeit von verschiedenen Einflussgroessen wie Standort, Nadelalter, Baumalter und Position von Probenaesten innerhalb der Baumkrone erarbeitet. Danach wurden die krankheitsbedingten Veraenderungen im Hormonhaushalt der entsprechenden Versuchsbaeume charakterisiert. Die Schadgase SO{sub 2} und Ozon wurden in die Untersuchungen einbezogen. Die Untersuchungen ergaben, dass die zeitliche Entwicklung von Physiologie und Strukturmerkmalen auf eine Alterung der Nadeln kranker Baeume hinweist, doch entsprechen die damit einhergehenden Veraenderungen im Hormonhaushalt offenbar nicht der hormonellen Steuerung der natuerlichen Alterung von Nadeln. Als Ursachen der beobachteten Schaedigungen scheiden nach den vorliegenden Untersuchungen ein starker SO{sub 2}-Einfluss oder ein Mineralstoffmangel am Standort aus. Es gelang nicht, die Rolle des Ozons zu klaeren. (orig./MG)

  3. Studies on the binary complexes of some transition metals with indolyl-3-acetic acid by potentiometry%吲哚-3-乙酸与部分过渡金属离子M(Ⅱ)二元配合物的pH电位法研究

    Institute of Scientific and Technical Information of China (English)

    朱元成; 董晓宁; 王兆吉; 郭莉芳

    2007-01-01

    在25℃,I=0.10 mol/L KNO3的实验条件下,用pH电位法测定了吲哚-3-乙酸(IAA)在甲醇-水混合溶剂中的质子化常数,讨论了有机溶剂对质子化常数的影响,结果表明在实验范围内溶剂甲醇含量对质子化常数的影响呈线性关系.确定了二元体系M(Ⅱ)-IAA(M=Fe、Co、Ni、Cu、Zn和Cd)在甲醇含量为50%(V/V)的混合溶剂中主要存在的配合物物种,并测定了配合物的稳定常数.实验数据的处理运用计算机程序Hyperquad、Glee和Hyss完成.

  4. The effect of phytohormones on the dynamics of protein biosynthesis and enzyme activity in linted and naked cotton seed

    Science.gov (United States)

    We determined the effect of exogenous indole-3-acetic acid, a-naphthylene-3-acetic acid and gibberellic acid (GA3) on the enzymatic activity of glucansynthase, peroxidase and cellulase in ovule development of naked L-70 and linted AN-Bayaut-2 cotton (Gossypium hirsutum L.) seeds. We isolated a prote...

  5. Synthesis of 3-deuterated diazepam and nordiazepam 4-oxides and their use in the synthesis of other 3-deuterated derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Yang, S.K.; Tang, R.; Quanlong Pu [Uniformed Services Univ. of the Health Sciences, Bethesda, MD (United States). Dept. of Medicine

    1996-08-01

    The protons at 3-positions of diazepam 4-oxide and nordiazepam 4-oxide underwent an efficient deuterium exchange via keto-enol tautomerism in deuterated alkaline methanol. The 3-dideuterated 4-oxides were each used as a starting material to synthesize 3-monodeuterated oxazepam and its 3-acetate, 3-monodeuterated temazepam and its 3-acetate, and 3-dideuterated diazepam and nordiazepam. (author).

  6. Rhodanineacetic acid derivatives as potential drugs: preparation, hydrophobic properties and antifungal activity of (5-arylalkylidene-4-oxo-2-thioxo-1,3-thiazolidin-3-yl)acetic acids

    National Research Council Canada - National Science Library

    Dolezel, Jan; Hirsova, Petra; Opletalova, Veronika; Dohnal, Jiri; Marcela, Vejsova; Kunes, Jiri; Jampilek, Josef

    2009-01-01

    .... The general synthetic approach to all synthesized compounds is presented. Lipophilicity of all the discussed rhodanine-3-acetic acid derivatives was analyzed using a reversed phase high performance liquid chromatography (RP-HPLC) method...

  7. Download this PDF file

    African Journals Online (AJOL)

    chlorophyll and biochemical contents of S.mombin were determined using standard ... coconut water has the potential to increase growth and nutritional value of S. ..... Personal. Communication. Kadiri, M. 1999. Effect of Indole-3-acetic acid.

  8. Agrosearch 2015. Corrected

    African Journals Online (AJOL)

    Growth and Differentiation in Plants.New Delhi ... Associated with Genetic Increases in Yield of Zea mays L. Agronomy Journal69:8184. Naeem, M. ... Indole- 3 Acetic Acid is Related to Secondary Xylem Development in Hybrid Aspen. Plant.

  9. [Role of auxin in induction of polarity in zygotes of Fucus vesiculosus L].

    Science.gov (United States)

    Polevoĭ, V V; Tarakhovskaia, E R; Maslov, Iu I; Polevoĭ, A V

    2003-01-01

    We studied the effects of auxin (indolyl-3 acetic acid) on formation of the primary polarity axis in zygotes of the brown algae Fucus vesiculosus. Within the first 2.5 h after fertilization, the zygotes release this phytohormone in the environment. The treatment of developing zygotes with the inhibitor of indolyl-3-acetic acid transport from the cell triiodobenzoic acid at 5 mg/l arrests the auxin secretion and leads to its accumulation in the cells. This causes a significant delay in zygote polarization. The treatment of zygotes with the exogenous indolyl-3-acetic acid at 1 mg/l stimulates cell polarization and formation of a rhizoid process. When auxin was added to the medium with triiodobenzoic acid, the inhibitory effect of the latter was fully relieved. It has been proposed that the content of indolyl-3-acetic acid in the environment is a key factor in the induction of polarity of the F. vesiculosus zygotes.

  10. The analgesic effect of diclofenac sodium administered via the ...

    African Journals Online (AJOL)

    2016-02-08

    Feb 8, 2016 ... diclofenac sodium, 300 mg/kg of 3% acetic acid was injected via intraperitoneal route, and the rats were ... body of experimental evidence indicates that such drugs .... subcutaneously in the dorsum with a pediatric epidural.

  11. The auxin concentration in sixteen Chinese marine algae

    Science.gov (United States)

    Han, Lijun

    2006-09-01

    The author determined the occurrence of indole-3-acetic acid in sixteen Chinese marine algae collected from the east coast of China with fluorescence spectrophotometry (FS) and wheat coleoptile bioanalysis methods (WCB). The concentration of indole-3-acetic acid (IAA) presented was from 1.1 46.9 ng/g Fw (fresh weight) with FS and 5.3 110.2 ng/g Fw with WCB. The results by the two methods were in the orders of 10-3 103 ng/g Fw reported previously from multiple references.

  12. Response of pine hypocotyl sections to growth regulators and related substances

    Directory of Open Access Journals (Sweden)

    J. Zakrzewski

    2015-01-01

    Full Text Available Growth response of Pinus silvestris hypocotyl sections to some synthetic growth regulators and related substances was studied. Elongation of hypocotyl sections was stimulated by naphtaleneacetic acid, indole-3-acetic acid, in-dole-3-propionic acid, indole-3-butyric acid, 2,4-dichlorophenoxyacetic acid, indoleaoetic amide, indoleacetic nitrile and coumarin. Indole-3-acetic acid and naphtaleneacetic acid extended period of growth up to 16 and 24 hours, respectively. Growth was inhibited by kinetin, trans-cinnamic acid and 2,3,5-tri-iodobenzoic acid. No effect of gibberellic acid, tryptophan and biotin was observed.

  13. Three new multiflorane-type triterpenes from pumpkin (Cucurbita maxima) seeds.

    Science.gov (United States)

    Kikuchi, Takashi; Takebayashi, Mika; Shinto, Mayumi; Yamada, Takeshi; Tanaka, Reiko

    2013-05-14

    Three new multiflorane-type triterpenes; 7a-methoxymultiflor-8-ene-3a,29-diol 3-acetate-29-benzoate (1), 7-oxomultiflor-8-ene-3a,29-diol 3-acetate-29-benzoate (2), and multiflora-7,9(11)-diene-3a,29-diol 3-p-hydroxybenzoate-29-benzoate (3), were isolated from seeds of Cucurbita maxima, along with three known compounds. Compound 3 and multiflora-7,9(11)-diene-3a-29-diol 3-benzoate (5) exhibited potent inhibitory effects on melanogenesis, with low cytotoxicities, and 2 exhibited single-digit micromolar cytotoxicity against HL-60 and P388 cells.

  14. The auxin concentration in sixteen Chinese marine algae

    Institute of Scientific and Technical Information of China (English)

    HAN Lijun

    2006-01-01

    The author determined the occurrence of indole-3-acetic acid in sixteen Chinese marine algae collected from the east coast of China with fluorescence spectrophotometry (FS) and wheat coleoptile bioanalysis methods (WCB). The concentration of indole-3-acetic acid (IAA) presented was from 1.1-46.9 ng/g Fw (fresh weight) with FS and 5.3-110.2 ng/g Fw with WCB. The results by the two methods were in the orders of 10-3-103 ng/g Fw reported previously from multiple references.

  15. SIMULTANEOUS MEASUREMENT OF EXTRACELLULAR MORPHINE AND SEROTONIN IN BRAIN-TISSUE AND CSF BY MICRODIALYSIS IN AWAKE RATS

    NARCIS (Netherlands)

    MATOS, FF; ROLLEMA, H; BASBAUM, AI

    1992-01-01

    In this report, we describe an HPLC with electrochemical detection assay for the simultaneous measurement of levels of morphine, serotonin, 5-hydroxyindole-3-acetic acid, and homovanillic acid in dialysates of various brain areas and CSF in the awake rat. Morphine could be detected in the dialysates

  16. Effects of phenolic compounds on adventitious root formation and oxidative decarboxylation of applied indoleacetic acid in Malus 'Jork 9'

    NARCIS (Netherlands)

    Klerk, de G.J.M.; Guan, H.; Huisman, P.; Marinova, S.

    2011-01-01

    Stem slices (1-mm thick) cut from apple microshoots were cultured on a modified Murashige-Skoog medium with indole-3-acetic acid (IAA) or α-naphthaleneacetic acid (NAA), and increasing concentrations of various phenolic compounds. Both auxins were added at a concentration suboptimal for rooting. Ind

  17. Knocking down expression of the auxin-amidohydrolase IAR3 alters defense responses in Solanaceae family plants

    NARCIS (Netherlands)

    Ippolito, D' Sebastian; Vankova, Radomira; Joosten, Matthieu H.A.J.; Casalongué, Claudia A.; Fiol, Diego F.

    2016-01-01

    In plants, indole-3-acetic acid (IAA) amido hydrolases (AHs) participate in auxin homeostasis by releasing free IAA from IAA-amino acid conjugates. We investigated the role of IAR3, a member of the IAA amido hydrolase family, in the response of Solanaceous plants challenged by biotrophic and hemi

  18. Enzymic synthesis of indole-3-acetyl-1-O-beta-d-glucose. II. Metabolic characteristics of the enzyme

    Science.gov (United States)

    Leznicki, A. J.; Bandurski, R. S.

    1988-01-01

    The synthesis of indole-3-acetyl-1-O-beta-D-glucose from indole-3-acetic acid (IAA) and uridine diphosphoglucose (UDPG) has been shown to be a reversible reaction with the equilibrium away from ester formation and toward formation of IAA. The enzyme occurs primarily in the liquid endosperm of the corn kernel but some activity occurs in the embryo. It is relatively specific showing no glucose ester formation with oxindole-3-acetic acid or 7-hydroxy-oxindole-3-acetic acid, and low activity with phenylpropene acids, such as rho-coumaric acid. The enzyme is also specific for the nucleotide sugar showing no activity with UDPGalactose or UDPXylose. The enzyme is inhibited by inorganic pyrophosphate, by phosphate esters and by phospholipids, particularly phosphatidyl ethanolamine. The enzyme is inhibited by zeatin, by 2,4-dichlorophenoxy-acetic acid, by IAA-myo-inositol and IAA-glucan, but not by zeatin riboside, and only weakly by gibberellic acid, abscisic acid and kinetin. The reaction is slightly stimulated by both calcium and calmodulin and, in some cases, by thiol compounds. The role of this enzyme in the homeostatic control of indole-3-acetic acid levels in Zea mays is discussed.

  19. Plant-microbe interactions: Plant hormone production by phylloplane fungi. Research report

    Energy Technology Data Exchange (ETDEWEB)

    Tuomi, T.; Ilvesoksa, J.; Rosenqvist, H.

    1993-06-23

    The molds Botrytis cinerea, Cladosporium cladosporioides and the yeast Aureobasidium pullulans, isolated from the leaves of three short-rotation Salix clones, were found to produce indole-3-acetic acid (a growth promoter of plants). Abscisic acid (a growth inhibitor of plants) production was detected in B. cinerea. The contents of indole-3-acetic acid and abscisic acid in the leaves of the Salix clones and the amounts of fungal propagules in these leaves were also measured, in order to evaluate whether the amounts of plant growth regulators produced by the fungi would make a significant contribution to the hormonal quantities of the leaves. The content of abscisic acid, and to a lesser degree that of indole-3-acetic acid, showed a positive correlation with the frequency of infection by the hormone producing organisms. The amounts of hormone producing fungi on leaves that bore visible colonies were, however, not sufficiently high to support the argument that neither the fungal production of abscisic nor indole-3-acetic acid would to a significant degree contribute to the hormonal contents of the leaves of the Salix clones.

  20. Effects of phenolic compounds on adventitious root formation and oxidative decarboxylation of applied indoleacetic acid in Malus 'Jork 9'

    NARCIS (Netherlands)

    Klerk, de G.J.M.; Guan, H.; Huisman, P.; Marinova, S.

    2011-01-01

    Stem slices (1-mm thick) cut from apple microshoots were cultured on a modified Murashige-Skoog medium with indole-3-acetic acid (IAA) or α-naphthaleneacetic acid (NAA), and increasing concentrations of various phenolic compounds. Both auxins were added at a concentration suboptimal for rooting. Ind

  1. NEW NATURAL GROWTH PROMOTING SUBSTANCES IN YOUNG CITRUS FRUIT.

    Science.gov (United States)

    KHALIFAH, R A; LEWIS, L N; COGGINS, C W

    1963-10-18

    A naturally occurring compound that induces curvature in the Avena coleoptile test has been found in young orange fruits. Cochromatography with C(14)-labeled indole-3-acetic acid, plus excitation and fluorescence spectra determinations, indicates that this compound is not one of the known indoles or gibberellins.

  2. Synthesis of 7-dehydrocholesterol through hexacarbonyl ...

    African Journals Online (AJOL)

    Preferred Customer

    2011 Chemical Society of Ethiopia. ______ ... topic of interest for the synthesis of 7-dehydrocholesterol. Allylic oxidation of ... experimental design. Palladium catalyzed ... Scheme 2 shows a simple description of the whole process. .... dehydrocholesterol-3-acetate was quantitatively analyzed by HPLC at 281 nm. The mobile.

  3. 21 CFR 177.1330 - Ionomeric resins.

    Science.gov (United States)

    2010-04-01

    ... acid groups may optionally be neutralized to form sodium or zinc salts. (c) The finished food-contact... sugar or both, and including oil-in-water emulsions of low- or high-fat content Water, n-heptane. 2... emulsions of low- or high-fat content n-heptane, water, 3% acetic acid. 3. Aqueous, acid or nonacid...

  4. Simple Identification of the Neutral Chlorinated Auxin in Pea by Thin Layer Chromatography

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1980-01-01

    One of the neutral chlorinated auxins of immature pea seeds was readily identified by thin layer procedures simple enough to serve in student's laboratory courses. 4-Chloroindole-3-acetic acid methyl ester was extracted from 50 g of commercial, frozen peas by either water or acetone, concentrated...

  5. Controlled indole-3-acetaldoxime production through ethanol-induced expression of CYP79B2

    DEFF Research Database (Denmark)

    Mikkelsen, M.D.; Fuller, V.L.; Hansen, Bjarne Gram

    2009-01-01

    Indole-3-acetaldoxime (IAOx) is a key branching point between primary and secondary metabolism. IAOx serves as an intermediate in the biosynthesis of indole glucosinolates (I-GLSs), camalexin and the plant hormone indole-3-acetic acid (IAA). The cytochrome P450s CYP79B2 and CYP79B3 catalyze the c...

  6. Substituted Indoleacetic Acids Tested in Tissue Cultures

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1978-01-01

    Monochloro substituted IAA inhibited shoot induction in tobacco tissue cultures about as much as IAA. Dichloro substituted IAA inhibited shoot formation less. Other substituted IAA except 5-fluoro- and 5-bromoindole-3-acetic acid were less active than IAA. Callus growth was quite variable...

  7. Phenol-oxidizing peroxidases contribute to the protection of plants from ultraviolet radiation stress

    NARCIS (Netherlands)

    Jansen, M.A.K.; Noort, van den R.E.; Tan, M.Y.A.; Prinsen, E.; Lagrimini, L.M.; Thorneley, R.N.F.

    2001-01-01

    We have studied the mechanism of UV protection in two duckweed species (Lemnaceae) by exploiting the UV sensitivity of photosystem II as an in situ sensor for radiation stress. A UV-tolerant Spirodela punctata G.F.W. Meyer ecotype had significantly higher indole-3-acetic acid (IAA) levels than a UV-

  8. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Normanly, J.

    1999-11-29

    The primary goal was the characterization of tryptophan (Trp)-independent biosynthesis of the auxin indole-3-acetic acid (IAA). Our work and that of others indicates that indole is a precursor to IAA in a Trp-independent pathway and the objectives of this grant have been the isolation of indole-metabolizing genes from Arabidopsis.

  9. Synthesis of Benzofuran Analogue of Go6976, an Isoform Selective Protein Kinase C Inhibitor

    Institute of Scientific and Technical Information of China (English)

    MA, Da-Wei; ZHANG, Xin-Rong; WU, Shi-Hui; TAO, Feng-Gang

    2001-01-01

    Based on the structure of Go6976, a known isoform-selective protein kinase C inhibitor, a benzofuran analogue (1) was designed. This analogue was synthesized by coupling of benzofuran 3-acetic acid and 8-oxo-tryptamine and subsequent intramolecular Dieckmann condensation, alkylation, oxidative photocyclization and cyanation reaction of mesylate.

  10. New analogues of ACPD with selective activity for group II metabotropic glutamate receptors

    DEFF Research Database (Denmark)

    Bräuner-Osborne, Hans; Madsen, U; Mikiciuk-Olasik, E

    1997-01-01

    In this study we have determined the pharmacology of a series of 1-aminocyclopentane-1,3-dicarboxylic acid (1,3-ACPD) analogues at cloned metabotropic glutamic acid (mGlu) receptors. The new analogues comprise the four possible stereoisomers of 1-amino-1-carboxycyclopentane-3-acetic acid (1,3-homo...

  11. Microbial Degradation of Indole and Its Derivatives

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Arora

    2015-01-01

    Full Text Available Indole and its derivatives, including 3-methylindole and 4-chloroindole, are environmental pollutants that are present worldwide. Microbial degradation of indole and its derivatives can occur in several aerobic and anaerobic pathways; these pathways involve different known and characterized genes. In this minireview, we summarize and explain the microbial degradation of indole, indole-3-acetic acid, 4-chloroindole, and methylindole.

  12. VvMJE1 of the grapevine (Vitis vinifera) VvMES methylesterase family encodes for methyl jasmonate esterase and has a role in stress response

    Science.gov (United States)

    The known members of the plant methyl esterase (MES) family catalyze hydrolysis of a C-O ester linkage of methyl esters of several phytohormones including indole-3-acetic acid, salicylic acid, and jasmonic acid. The genome of grapevine (Vitis vinifera) was found to contain 15 MES genes, designated V...

  13. High-Quality Draft Whole-Genome Sequences of Three Strains of Enterobacter Isolated from Jamaican Dioscorea cayenensis (Yellow Yam)

    OpenAIRE

    Gan, Han Ming; Triassi, Alexander J.; Wheatley, Matthew S.; Savka, Michael A.; Hudson, André O.

    2014-01-01

    Here we report the whole-genome sequences of three endophytic bacteria, Enterobacter sp. strain DC1, Enterobacter sp. strain DC3, and Enterobacter sp. strain DC4, from root tubers of the yellow yam plant, Dioscorea cayenensis. Preliminary analyses suggest that the genomes of the three bacteria contain genes involved in acetoin and indole-3-acetic acid metabolism.

  14. The influence of the fungal pathogen Mycocentrospora acerina on the proteome and polyacetylenes and 6-methoxymellein in organic and conventionally cultivated carrots (Daucus carota) during post harvest storage

    DEFF Research Database (Denmark)

    Louarn, Sébastien; Nawrocki, Arkadiusz; Edelenbos, Merete

    2012-01-01

    month of storage than conventional ones, but no differences were apparent after four or six months storage. Levels of polyacetylenes (falcarinol, falcarindiol and falcarindiol-3-acetate) did not change, whereas the isocoumarin phytoalexin (6-methoxymellein) accumulated in infected tissue as well...

  15. Protein ubiquitination in auxin signaling and transport

    NARCIS (Netherlands)

    Santos Maraschin, Felipe dos

    2009-01-01

    What makes plant shoots grow towards the light, and plant roots grow down into the soil? This was a question that Charles Darwin asked himself, and his experiments more than a century ago to find the answer laid the basis for the identification of the growth hormone auxin. Auxin, or indole-3-acetic

  16. Biodegradation of 3-Nitrotyrosine by Burkholderia sp. Strain JS165 and Variovorax paradoxus JS171

    Science.gov (United States)

    2006-02-01

    and B. Minambres. 2004. The homogentisate pathway: a central catabolic pathway involved in the degradation of L- phenylalanine , L-tyrosine, and 3...acetate-3- hydroxylase . A two-protein component enzyme. J. Biol. Chem. 267:25848–25855. 4. Bruhn, C., H. Lenke, and H.-J. Knackmuss. 1987. Nitrosubstituted

  17. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Normanly, J.

    1999-11-29

    The primary goal was the characterization of tryptophan (Trp)-independent biosynthesis of the auxin indole-3-acetic acid (IAA). Our work and that of others indicates that indole is a precursor to IAA in a Trp-independent pathway and the objectives of this grant have been the isolation of indole-metabolizing genes from Arabidopsis.

  18. Sardisterol, A New Polyhydroxylated Sterol from the Soft Coral Sarcophyton digitatum Moser

    Institute of Scientific and Technical Information of China (English)

    SU, Jing-Yu; YANG, Ruo-Lin

    2001-01-01

    A new polyhydroxylated sterol, named sardisterol, was isolated from the soft coral Sarcophyton digitatum Moser. Its structure was determined as (22R, 24ξ)-methyicholest-5-en-3β,22, 25, 28-tetraol-3-acetate on the basis of spectroscopic methods.

  19. Effect of asymmetric auxin application on Helianthus hypocotyl curvature

    Science.gov (United States)

    Migliaccio, F.; Rayle, D. L.

    1989-01-01

    Indole-3-acetic acid was applied asymmetrically to the hypocotyls of sunflower (Helianthus annuus L.) seedlings. After 5 hours on a clinostat, auxin gradients as small as 1 to 1.3 produced substantial (more than 60 degrees) hypocotyl curvature. This result suggests the asymmetric growth underlying hypocotyl gravitropism can be explained by lateral auxin redistribution.

  20. Gravity-induced asymmetric distribution of a plant growth hormone

    Science.gov (United States)

    Bandurski, R. S.; Schulze, A.; Momonoki, Y.

    1984-01-01

    Dolk (1936) demonstrated that gravistimulation induced an asymmetric distribution of auxin in a horizontally-placed shoot. An attempt is made to determine where and how that asymmetry arises, and to demonstrate that the endogenous auxin, indole-3-acetic acid, becomes asymmetrically distributed in the cortical cells of the Zea mays mesocotyl during 3 min of geostimulation. Further, indole-3-acetic acid derived by hydrolysis of an applied transport form of the hormone, indole-3-acetyl-myo-inositol, becomes asymmetrically distributed within 15 min of geostimulus time. From these and prior data is developed a working theory that the gravitational stimulus induces a selective leakage, or secretion, of the hormone from the vascular tissue to the cortical cells of the mesocotyl.

  1. Cucumber Seedling Indoleacetaldehyde Oxidase 1

    Science.gov (United States)

    Bower, Peter J.; Brown, Hugh M.; Purves, William K.

    1978-01-01

    Extracts of light-grown Cucumis sativus L. seedlings catalyzed the oxidation of indole-3-acetaldehyde to indole-3-acetic acid. No added cofactors were required. Inhibitor studies indicated that the enzyme is a metalloflavoprotein. While indole-3-aldehyde, benzaldehyde, and phenylacetaldehyde partially inhibited the oxidation of indole-3-acetaldehyde, suggesting that they may serve as alternative substrates, it is proposed that indoleacetaldehyde is the major substrate in vivo. 2,4-Dichlorophenoxyacetic acid strongly inhibited the indoleacetaldehyde oxidase activity, and it is proposed that this enzyme may be subject in vivo to feedback inhibition by indole-3-acetic acid. The enzyme was activated by brief heating or by treatment with mercaptoethanol. PMID:16660220

  2. Biotransformation of Indole to 3-Methylindole by Lysinibacillus xylanilyticus Strain MA

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Arora

    2015-01-01

    Full Text Available An indole-biotransforming strain MA was identified as Lysinibacillus xylanilyticus on the basis of the 16S rRNA gene sequencing. It transforms indole completely from the broth culture in the presence of an additional carbon source (i.e., sodium succinate. Gas-chromatography-mass spectrometry identified indole-3-acetamide, indole-3-acetic acid, and 3-methylindole as transformation products. Tryptophan-2-monooxygenase activity was detected in the crude extracts of indole-induced cells of strain MA, which confirms the formation of indole-3-acetamide from tryptophan in the degradation pathway of indole. On the basis of identified metabolites and enzyme assay, we have proposed a new transformation pathway for indole degradation. Indole was first transformed to indole-3-acetamide via tryptophan. Indole-3-acetamide was then transformed to indole-3-acetic acid that was decarboxylated to 3-methylindole. This is the first report of a 3-methylindole synthesis via the degradation pathway of indole.

  3. Influence of aqueous food simulants on potential nanoparticle detection in migration studies involving nanoenabled food-contact substances.

    Science.gov (United States)

    Addo Ntim, Susana; Thomas, Treye A; Noonan, Gregory O

    2016-05-01

    Research focused on assessing potential consumer exposure to nanoparticles released from nano-enabled food-contact materials (FCMs) has often reached conflicting conclusions regarding the detection of migrating nanoparticles. These conflicting conclusions, coupled with the potential for nanoparticles to be unstable in certain food simulants, has necessitated a closer look at the role played by food simulants recommended for use in nanoparticle migration evaluation. The influence of aqueous food simulants on nanoparticles under migration evaluation conditions is reported herein. The stability of silver nanoparticles (AgNP) spiked into three food simulants (water, 10% ethanol and 3% acetic acid) was investigated using asymmetric flow field-flow fractionation (AF4), ultrafiltration, electron microscopy (EM), and single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS). While 3% acetic acid induced significant oxidative dissolution of AgNP to silver ions, there were very minor to no changes in the physicochemical properties of AgNP in water and 10% ethanol.

  4. A multiplex GC-MS/MS technique for the sensitive and quantitative single-run analysis of acidic phytohormones and related compounds, and its application to Arabidopsis thaliana.

    Science.gov (United States)

    Müller, Axel; Düchting, Petra; Weiler, Elmar W

    2002-11-01

    A highly sensitive and accurate multiplex gas chromatography-tandem mass spectrometry (GC-MS/MS) technique is reported for indole-3-acetic acid, abscisic acid, jasmonic acid, 12-oxo-phytodienoic acid and salicylic acid. The optimized setup allows the routine processing and analysis of up to 60 plant samples of between 20 and 200 mg of fresh weight per day. The protocol was designed and the equipment used was chosen to facilitate implementation of the method into other laboratories and to provide access to state-of-the-art analytical tools for the acidic phytohormones and related signalling molecules. Whole-plant organ-distribution maps for indole-3-acetic acid, abscisic acid, jasmonic acid, 12-oxo-phytodienoic acid and salicylic acid were generated for Arabidopsis thaliana (L.) Heynh. For leaves of A. thaliana, a spatial resolution of hormone quantitation down to approximately 2 mm(2) was achieved.

  5. Isolasi dan karakterisasi senyawa metabolit sekunder dari bakteri laut Streptomyces sp.

    Directory of Open Access Journals (Sweden)

    Muhammad bahi

    2012-12-01

    Full Text Available Streptomyces is one of bacterial genus which has been considered as a potential source of many novel antibiotics from both terrestrial and marinemicroorganism. In this paper, four secondary metabolites have been isolated and characterized from a marine Streptomyces sp. B5798, namely phydroxyphenylaceticacid (2, indole-3-carboxylic acid (3, indole-3-acetic acid (4, and Macrolactin A (5, respectively. Two of them are commoncompounds, namely indole-3-carboxylic acid (3 and indole-3-acetic acid (4. The 3,4-dihydroxybenzaldehyde is a degradation product of phydroxyphenylacetic(2 in microorganism. Macrolactin A (5 showed cytotoxicity against brine shrimps test (A. salina. All structures of the isolatedcompounds were elucidated based on spectroscopic and mass spectrometry data.

  6. Structures of spider toxins: hydroxyindole-3-acetylpolyamines and a new generalized structure of type-E compounds obtained from the venom of the Joro spider, Nephila clavata.

    Science.gov (United States)

    Hisada, M; Fujita, T; Naoki, H; Itagaki, Y; Irie, H; Miyashita, M; Nakajima, T

    1998-08-01

    Facile structure determination of acylpolyamines, glutamatergic nerve blocker obtained from the venom of the Joro spider (Nephila clavata) was carried out with the use of micro-column LC/MS and high energy collision induced dissociation (CID) mass spectrometry. 6-hydroxyindole-3-acetyl was proposed previously as a putative partial structure, for the acyl moiety of hydroxyindole-type polyamines (NPTX-1 to -6). The NMR data obtained for NPTX-6, NPTX-687 and hydroxyindole-3-acetic acid which was released by acid hydrolysis of Nephila clavata crude venom extracts proved that the lipophilic head is the 4-hydroxyindole-3-acetic acid. Various hydroxyindole-3-acetyl polyamines were found in N. Clavata venom and characterized by mass spectrometry. As a result, type-E, a new class of generalized acylpolyamine structure was proposed in addition to the previously reported polyamine backbones type-A to -D.

  7. Effects of harvesting date and storage on the amounts of polyacetylenes in carrots, Daucus carota.

    Science.gov (United States)

    Kjellenberg, Lars; Johansson, Eva; Gustavsson, Karl-Erik; Olsson, Marie E

    2010-11-24

    The amounts of three main polyacetylenes in carrots; falcarinol, falcarindiol, and falcarindiol-3-acetate, were determined by HPLC, during three seasons, in carrots harvested several times per season and at different locations in Sweden. The amounts of falcarindiol first decreased from a relatively high level and then increased later in the harvest season. The amounts of falcarindiol-3-acetate showed similar variations, whereas the amounts of falcarinol did not exhibit any significant variation during the harvest season. During storage the amount of polyacetylenes leveled off, increasing in samples initially low and decreasing in samples initially high in polyacetylenes. The amounts of all polyacetylenes varied significantly due to external factors and between stored and fresh samples. This variation opens up possibilities to achieve a chemical composition of polyacetylenes at harvest that minimizes the risk of bitter off-taste and maximizes the positive health effects reported in connection with polyacetylenes in carrots.

  8. Migration of formaldehyde and melamine monomers from kitchen- and tableware made of melamine plastic

    DEFF Research Database (Denmark)

    Lund, K.H.; Petersen, J.H.

    2006-01-01

    Migration of one or both formaldehyde and/or melamine monomers was found in seven of ten tested melamine samples bought on the Danish market. The samples were a bowl, a jug, a mug, a ladle, and different cups and plates. No violation of the European Union-specific migration limits for melamine (30...... mg kg(-1)) and formaldehyde (15 mg kg(-1)) was found after three successive exposures to the food stimulant 3% acetic acid after 2 h at 70 degrees C. To investigate the effects of long-term use, migration tests were performed with two types of cups from a day nursery. Furthermore, medium-term use...... was studied by ten successive exposures of a plate to 3% acetic acid for 30 min at 95 degrees C. The results indicate that continuous migration of formaldehyde and melamine takes place during the lifetime of these articles. The molar ratio of released formaldehyde to melamine was seen to decrease from 12...

  9. Natural Chlorinated Auxins Labeled with Radioactive Chloride in Immature Seeds

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1975-01-01

    Immature seeds were harvested from 15 species grown in perlite/vermiculite containing 36Cl-, but with very low levels of cold Cl-. Autoradiograms of one- and two-dimensional thin layer chromatograms of butanol extracts of lyophilized seeds indicated several radioactive compounds besides the 36Cl......- in many species. In pea the radioactivity cochromatographed with 4-(or 6-)chloroindolyl-3-acetic acid and its methyl ester; in other species radioactivity was found near these chlorinated indolyl-acetic acid markers....

  10. High temperature promotes auxin-mediated hypocotyl elongation in Arabidopsis

    OpenAIRE

    Gray, William M; Östin, Anders; Sandberg, Göran; Romano, Charles P.; Estelle, Mark

    1998-01-01

    Physiological studies with excised stem segments have implicated the plant hormone indole-3-acetic acid (IAA or auxin) in the regulation of cell elongation. Supporting evidence from intact plants has been somewhat more difficult to obtain, however. Here, we report the identification and characterization of an auxin-mediated cell elongation growth response in Arabidopsis thaliana. When grown in the light at high temperature (29°C), Arabidopsis seedlings exhibit dramatic hypocotyl elongation co...

  11. Dynamics of auxin movement in the gravistimulated leaf-sheath pulvinus of oat (Avena sativa)

    Science.gov (United States)

    Brock, Thomas C.; Kapen, E. H.; Ghosheh, Najati S.; Kaufman, Peter B.

    1991-01-01

    The role of auxin redistribution in the graviresponse of the leaf-sheath pulvinus of oat was evaluated using H-3-indole-3-acetic acid (H-3-IAA) preloaded into isolated pulvini. Results obtained reveal that, while lateral transport of auxin occurs following gravistimulation, it is not necessary for a graviresponse. Localized changes in tissue responsiveness or the conversion of conjugated hormone to free hormone may suffice to drive the graviresponse.

  12. Phytohormone production by strains of Pantoea agglomerans from knots on olive plants caused by Pseudomonas savastanoi pv. savastanoi

    OpenAIRE

    Cimmino, A; A. Andolfi; MARCHI, G.; Surico, G.; Evidente, A

    2006-01-01

    Pantoea agglomerans is a common epiphyte of many plant species, and it is associated with Pseudomonas savastanoi pv. savastanoi in young and apparently intact olive knots. Strains of P. agglomerans collected from various olive groves in central Italy were studied for their ability to accumulate plant growth substances in culture. All the strains produced indole-3-aldehyde, indole-3-ethanol and indole-3-acetic acid (IAA), this last compound in amounts (average 8.7 mg l-1) comparabl...

  13. A proton wire and water channel revealed in the crystal structure of isatin hydrolase

    DEFF Research Database (Denmark)

    Bjerregaard-Andersen, Kaare; Sommer, Theis; Jensen, Jan Kristian;

    2014-01-01

    The high resolution crystal structures of isatin hydrolase from Labrenzia aggregata in the apo and the product state, are described. These are the first structures of a functionally characterized metal-dependent hydrolase of this fold. Isatin hydrolase converts isatin to isatinate and belongs to ...... of orthologous genes encoding isatin hydrolases within the prokaryotic kingdom. The isatin hydrolase orthologues found in human gut bacteria raise the question as to whether the indole-3-acetic acid degradation pathway is present in human gut flora....

  14. Determination of antimicrobial activity and resistance to oxidation of moringa peregrina seed oil.

    Science.gov (United States)

    Lalas, Stavros; Gortzi, Olga; Athanasiadis, Vasilios; Tsaknis, John; Chinou, Ioanna

    2012-02-24

    The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina was tested against Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Candida albicans, C. tropicalis and C. glabrata. The oil proved effective against all of the tested microorganisms. Standard antibiotics (netilmycin, 5-flucytocine, intraconazole and 7-amino-4-methylcoumarin-3-acetic acid) were used for comparison. The resistance to oxidation of the extracted seed oil was also determined.

  15. Determination of Antimicrobial Activity and Resistance to Oxidation of Moringa peregrina Seed Oil

    Directory of Open Access Journals (Sweden)

    Ioanna Chinou

    2012-02-01

    Full Text Available The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina was tested against Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Candida albicans, C. tropicalis and C. glabrata. The oil proved effective against all of the tested microorganisms. Standard antibiotics (netilmycin, 5-flucytocine, intraconazole and 7-amino-4-methylcoumarin-3-acetic acid were used for comparison. The resistance to oxidation of the extracted seed oil was also determined.

  16. Isolation and characterization of plant growth-promoting rhizobacteria from wheat rhizosphere and their effect on plant growth promotion

    OpenAIRE

    Majeed, Afshan; Abbasi, M. Kaleem; Hameed, Sohail; Imran, Asma; Rahim, Nasir

    2015-01-01

    The present study was conducted to characterize the native plant growth promoting (PGP) bacteria from wheat rhizosphere and root-endosphere in the Himalayan region of Rawalakot, Azad Jammu and Kashmir (AJK), Pakistan. Nine bacterial isolates were purified, screened in vitro for PGP characteristics and evaluated for their beneficial effects on the early growth of wheat (Triticum aestivum L.). Among nine bacterial isolates, seven were able to produce indole-3- acetic acid in tryptophan-suppleme...

  17. Correlations between Polyacetylene Concentrations in Carrot (Daucus carota L.) and Various Soil Parameters

    OpenAIRE

    Lars Kjellenberg; Eva Johansson; Karl-Erik Gustavsson; Artur Granstedt; Marie E. Olsson

    2016-01-01

    This study assessed the concentrations of three falcarinol-type polyacetylenes (falcarinol, falcarindiol, falcarindiol-3-acetate) in carrots and the correlations between these and different soil traits. A total of 144 carrot samples, from three different harvests taken a single season, were analysed in terms of their polyacetylene concentrations and root development. On one of the harvesting occasions, 48 soil samples were also taken and analysed. The chemical composition of the soil was foun...

  18. Evaluation of aeroponics for clonal propagation of Caralluma edulis, Leptadenia reticulata and Tylophora indica – three threatened medicinal Asclepiads

    OpenAIRE

    Mehandru, Pooja; Shekhawat, N. S.; Rai, Manoj K.; Kataria, Vinod; Gehlot, H. S.

    2014-01-01

    The present study explores the potential of aeroponic system for clonal propagation of Caralluma edulis (Paimpa) a rare, threatened and endemic edible species, Leptadenia reticulata (Jeewanti), a threatened liana used as promoter of health and Tylophora indica (Burm.f.) Merill, a valuable medicinal climber. Experiments were conducted to asses the effect of exogenous auxin (naphthalene acetic acid, indole-3-butyric acid, indole-3-acetic acid) and auxin concentrations (0.0, 0.5, 1, 2, 3, 4 or 5...

  19. Simultaneous determination of vanillylmandelic, homovanillic and 5-hydroxyindoleacetic acids in human urine by thin layer chromatography.

    Science.gov (United States)

    Alemany, G; Gamundí, A; Rosselló, C; Rial, R

    1996-01-01

    A TLC method for the simultaneous analysis of vanillylmandelic, homovanillic and 5-hydroxyindole-3-acetic acids in urine is described. The sample is cleaned up through a cyano minicolumn and extracted with diethyl ether. The acids are resolved by high-performance TLC, visualized by Folin Ciocalteau reagent and quantificated by densitometry at 600 nm with beta-(4-hydroxy-3-phenyl) acetic acid as the internal standard.

  20. Beneficial Bacteria Isolated from Grapevine Inner Tissues Shape Arabidopsis thaliana Roots

    OpenAIRE

    Enrico Baldan; Sebastiano Nigris; Chiara Romualdi; Stefano D'Alessandro; Anna Clocchiatti; Michela Zottini; Piergiorgio Stevanato; Andrea Squartini; Barbara Baldan

    2015-01-01

    We investigated the potential plant growth-promoting traits of 377 culturable endophytic bacteria, isolated from Vitis vinifera cv. Glera, as good biofertilizer candidates in vineyard management. Endophyte ability in promoting plant growth was assessed in vitro by testing ammonia production, phosphate solubilization, indole-3-acetic acid (IAA) and IAA-like molecule biosynthesis, siderophore and lytic enzyme secretion. Many of the isolates were able to mobilize phosphate (33%), release ammoniu...

  1. GRAPE MATURITY OF RHEIN RIESLING CULTIVAR AND SYNTHESIS OF ATYPICAL AGEING AROMA PRECURSORS

    Directory of Open Access Journals (Sweden)

    Snježana Jakobović

    2014-12-01

    Full Text Available The research on forming atypical aging off-flavor in wines (UTA was revealed a significant correlation between the UTA , the concentration of 2-aminoacetophenones (AAP and the wines produced from grapes affected by stress (lack of water or nitrogen supply, wines from grapes grown in high yielding vineyards or earlier harvested grapes. The aim of this study was to explore the different grape ripeness and synthesis of indole-3-acetic acid and tryptophan in must and wine of white cultivar Rhine Rieslin (Vitis vinifera L.. Treatments in the research have been the two periods of the grape harvesting dates (regular and late harvesting from two different locations (Mladice and Hrnjevac. Indole-3-acetic acid and tryptophan in must and wine were determined by high performance liquid chromatography with fluorescence detector. As the process of ripening was going on the concentration of indole-3-acetic acid and tryptophan in must and wines have been reduced regardless the year of research and vineyards positions. Wines produced from late harvested grapes have a lower possibility of the appearance of atypical aroma aging effect compared to the regular harvest.

  2. Interaction and signalling between a cosmopolitan phytoplankton and associated bacteria

    Science.gov (United States)

    Amin, S. A.; Hmelo, L. R.; van Tol, H. M.; Durham, B. P.; Carlson, L. T.; Heal, K. R.; Morales, R. L.; Berthiaume, C. T.; Parker, M. S.; Djunaedi, B.; Ingalls, A. E.; Parsek, M. R.; Moran, M. A.; Armbrust, E. V.

    2015-06-01

    Interactions between primary producers and bacteria impact the physiology of both partners, alter the chemistry of their environment, and shape ecosystem diversity. In marine ecosystems, these interactions are difficult to study partly because the major photosynthetic organisms are microscopic, unicellular phytoplankton. Coastal phytoplankton communities are dominated by diatoms, which generate approximately 40% of marine primary production and form the base of many marine food webs. Diatoms co-occur with specific bacterial taxa, but the mechanisms of potential interactions are mostly unknown. Here we tease apart a bacterial consortium associated with a globally distributed diatom and find that a Sulfitobacter species promotes diatom cell division via secretion of the hormone indole-3-acetic acid, synthesized by the bacterium using both diatom-secreted and endogenous tryptophan. Indole-3-acetic acid and tryptophan serve as signalling molecules that are part of a complex exchange of nutrients, including diatom-excreted organosulfur molecules and bacterial-excreted ammonia. The potential prevalence of this mode of signalling in the oceans is corroborated by metabolite and metatranscriptome analyses that show widespread indole-3-acetic acid production by Sulfitobacter-related bacteria, particularly in coastal environments. Our study expands on the emerging recognition that marine microbial communities are part of tightly connected networks by providing evidence that these interactions are mediated through production and exchange of infochemicals.

  3. Effect of a longitudinally applied voltage upon the growth of Zea mays seedlings

    Science.gov (United States)

    Desrosiers, M. F.; Bandurski, R. S.

    1988-01-01

    The electrical parameters that affect young seedling growth were investigated. Voltages ranging from 5 to 40 volts were applied longitudinally along the mesocotyl region of 4-day old Zea mays L. (cv Silver Queen) seedlings for periods of 3 or 4 hours. It was determined that: (a) making the tips of the seedlings electrically positive relative to the base strongly inhibited shoot growth at 5 volts, whereas the reverse polarity had no effect; (b) at higher voltages, making the tip of the seedlings negative caused less growth inhibition than the reverse polarity at each voltage level; (c) the higher the applied voltage the greater the degree of inhibition; and, (d) the more growth inhibition experienced by the plants the poorer, and slower, their recovery. Previous observations of a relationship between the amount of free indole-3-acetic acid in the mesocotyl cortex and the growth rate of the mesocotyl and of gravitropism-induced movement of labeled indole-3-acetic acid from the seed to the shoot lead to the prediction of a voltage-dependent gating of the movement of indole-3-acetic acid from the stele to the cortex. This provided the basis for attempting to alter the growth rate of seedlings by means of an applied voltage.

  4. Dynamic regulation of auxin oxidase and conjugating enzymes AtDAO1 and GH3 modulates auxin homeostasis

    Science.gov (United States)

    Mellor, Nathan; Band, Leah R.; Pěnčík, Aleš; Rashed, Afaf; Holman, Tara; Wilson, Michael H.; Voß, Ute; Bishopp, Anthony; King, John R.

    2016-01-01

    The hormone auxin is a key regulator of plant growth and development, and great progress has been made understanding auxin transport and signaling. Here, we show that auxin metabolism and homeostasis are also regulated in a complex manner. The principal auxin degradation pathways in Arabidopsis include oxidation by Arabidopsis thaliana gene DIOXYGENASE FOR AUXIN OXIDATION 1/2 (AtDAO1/2) and conjugation by Gretchen Hagen3s (GH3s). Metabolic profiling of dao1-1 root tissues revealed a 50% decrease in the oxidation product 2-oxoindole-3-acetic acid (oxIAA) and increases in the conjugated forms indole-3-acetic acid aspartic acid (IAA-Asp) and indole-3-acetic acid glutamic acid (IAA-Glu) of 438- and 240-fold, respectively, whereas auxin remains close to the WT. By fitting parameter values to a mathematical model of these metabolic pathways, we show that, in addition to reduced oxidation, both auxin biosynthesis and conjugation are increased in dao1-1. Transcripts of AtDAO1 and GH3 genes increase in response to auxin over different timescales and concentration ranges. Including this regulation of AtDAO1 and GH3 in an extended model reveals that auxin oxidation is more important for auxin homoeostasis at lower hormone concentrations, whereas auxin conjugation is most significant at high auxin levels. Finally, embedding our homeostasis model in a multicellular simulation to assess the spatial effect of the dao1-1 mutant shows that auxin increases in outer root tissues in agreement with the dao1-1 mutant root hair phenotype. We conclude that auxin homeostasis is dependent on AtDAO1, acting in concert with GH3, to maintain auxin at optimal levels for plant growth and development. PMID:27651495

  5. Analysis of primary aromatic amines (PAA) in black nylon kitchenware 2014

    DEFF Research Database (Denmark)

    Trier, Xenia; Granby, Kit

    shall be accompanied by appropriate documentation, including analytical results showing that it meets the requirements concerning the release of primary aromatic amines. 25 samples of black nylon kitchenware each of three articles were tested for migration of primary aromatic amines (PAA), using 3......% acetic acid as food simulant at an exposure temperature of 100°C and time from ½-4 hours, depending on the foreseeable use of the utensil. The samples were collected by the Norwegian Food Safety Authority at importers and retail shops. Of the 20 PAAs analysed. four PAAs were detected, being aniline (ANL...

  6. Auxin biosynthesis and storage forms.

    Science.gov (United States)

    Korasick, David A; Enders, Tara A; Strader, Lucia C

    2013-06-01

    The plant hormone auxin drives plant growth and morphogenesis. The levels and distribution of the active auxin indole-3-acetic acid (IAA) are tightly controlled through synthesis, inactivation, and transport. Many auxin precursors and modified auxin forms, used to regulate auxin homeostasis, have been identified; however, very little is known about the integration of multiple auxin biosynthesis and inactivation pathways. This review discusses the many ways auxin levels are regulated through biosynthesis, storage forms, and inactivation, and the potential roles modified auxins play in regulating the bioactive pool of auxin to affect plant growth and development.

  7. Improvement of buccal delivery of morphine using the prodrug approach

    DEFF Research Database (Denmark)

    Christrup, Lona Louring; Jørgensen, A.; Christensen, C.B.

    1997-01-01

    The feasibility of achieving buccal delivery of morphine using the prodrug approach was assessed by studies of bioactivation, in vitro permeation and in vivo absorption. The bioactivation of various morphine-3-esters was studied in human plasma and saliva. The in vitro permeation of morphine...... of 0.2. This discrepancy could however be explained by the enzymatic stability of the two esters in saliva, since it was found that morphine-3-propionate was more rapidly hydrolysed in saliva than was morphine-3-acetate. The study demonstrates that the buccal delivery of morphine can be markedly...

  8. Reference: 422 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available , that exhibits increased tolerance to the auxinic herbicide 2,4-dichlorophenoxyacetic acid (2,4-D...). Reciprocally, loss-of-function mutations in PDR9 confer 2,4-D hypersensitivity. This alt...ered auxin sensitivity defect of pdr9 mutants is specific for 2,4-D and closely related compounds as these m...butyric acid. We demonstrate that 2,4-D, but not indole-3-acetic acid transport is affected by mutations in ...pdr9, suggesting that the PDR9 transporter specifically effluxes 2,4-D out of plant cells without affecting

  9. Leaf and root volatiles produced by tissue cultures of Alpinia zerumbet (pers. Burtt & Smith under the influence of different plant growth regulators

    Directory of Open Access Journals (Sweden)

    Cristiane Pimentel Victório

    2011-01-01

    Full Text Available Volatiles produced by plantlets of Alpinia zerumbet were obtained by means of simultaneous distillation-extraction (SDE. The effects of indole-3-acetic acid, kinetin, thidiazuron and 6-benzylaminopurine on leaf and root volatile composition obtained by tissue cultures were investigated. A higher content of b-pinene and a lower content of sabinene were observed in leaf volatile of plantlets cultured in control, IAA and IAA+ TDZ media, as compared with those of donor plants. In vitro conditions were favorable to increase caryophyllene content. Volatile compounds from the root were characterized mainly by camphene, fenchyl-acetate and bornyl acetate; which constitute about 60% of total volatile.

  10. General Treatment

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    2011270 Anti-tumor effect of suicide gene therapy using chimeric promoter plus radiotherapy on cancer cell lines. SUN Wenjie(孫文潔),et al.Dept Radiat & Med Oncol,Zhongnan Hosp,Wuhan Univ,Wuhan 430071. Abstract:Objective To explore the synergistic anti-tumor effect of radiotherapy and horseradish peroxidase/prodrug indole-3-acetic acid(HRP/IAA) gene therapy system using chimeric hTERT promoter responsive to ionizing radiation.Methods The synthetic hTERT promoters containing four

  11. Reference: 141 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available s from the amino acid tryptophan (Trp), including the growth regulator indole-3-acetic acid (IAA) and defens...olate (IG) antiherbivore compounds. Here, we show that ATR1 overexpression confers elevated levels of IAA an...d IGs. In addition, we show that an atr1 loss-of-function mutation impairs expression of IG synthesis genes and confe...rs reduced IG levels. Furthermore, the atr1-defective mutation suppresse... John L|Merrikh Houra|Normanly Jennifer|Quiel Juan A|Silvestro Angela R|Smolen Gromoslaw A

  12. Micropropagation of Madhuca longifolia (Koenig) MacBride var. latifolia Roxb.

    Science.gov (United States)

    Rout, G R; Das, P

    1993-07-01

    Bud break and multiple shoots were induced in apical and axillary meristems derived from 10-d old seedlings of Madhuca longifolia var. latifolia on Murashige and Skoog (MS) medium supplemented with 1.0 mg/l N(6)-benzyladenine (BA) singly or in combinatiobn with 1-naphthalene acetic acid (NAA), indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). Excised shoots were rooted on half-strength MS with IBA (1.0 mg/l) after 18d of culture. Regenerated plantlets were acclimatized and successfully transferred to soil.

  13. Effect of ultrasound and blanching pretreatments on polyacetylene and carotenoid content of hot air and freeze dried carrot discs.

    Science.gov (United States)

    Rawson, A; Tiwari, B K; Tuohy, M G; O'Donnell, C P; Brunton, N

    2011-09-01

    The effect of ultrasound and blanching pretreatments on polyacetylene (falcarinol, falcarindiol and falcarindiol-3-acetate) and carotenoid compounds of hot air and freeze dried carrot discs was investigated. Ultrasound pretreatment followed by hot air drying (UPHD) at the highest amplitude and treatment time investigated resulted in higher retention of polyacetylenes and carotenoids in dried carrot discs than blanching followed by hot air drying. Freeze dried samples had a higher retention of polyacetylene and carotenoid compounds compared to hot air dried samples. Color parameters were strongly correlated with carotenoids (p<0.05). This study shows that ultrasound pretreatment is a potential alternative to conventional blanching treatment in the drying of carrots.

  14. Comparison of Polyacetylene Content in Organically and Conventionally Grown Carrots Using a Fast Ultrasonic Liquid Extraction Method

    DEFF Research Database (Denmark)

    Søltoft, Malene; Eriksen, Morten Rosbjørn; Träger, Anne Wibe Brændholt

    2010-01-01

    A rapid and sensitive analytical method for quantification of polyacetylenes in carrot roots was developed. The traditional extraction method (stirring) was compared to a new ultrasonic liquid processor (ULP)-based methodology using high-performance liquid chromatography−ultraviolet (HPLC−UV) and......, and falcarinol in year 1 were 222, 30, and 94 μg of falcarindiol equiv/g of dry weight, respectively, and 3−15% lower in year 2. The concentrations were not significantly influenced by the growth system, but a significant year−year variation was observed for falcarindiol-3-acetate....

  15. Comparison of dynamic changes in endogenous hormones and sugars between abnormal and normal Castanea mollissima

    Institute of Scientific and Technical Information of China (English)

    Tao Liu; Yunqian Hu; Xiaoxian Li

    2008-01-01

    To elucidate the possible functions of endogenous hormones in the flowering of chestnut, concentrations of four endogenous hormones [indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA), zeatin riboside (ZR)) and the soluble sugars content were measured in both normal and developmentally abnormal Chinese chestnut (Castanea mollissima) during flowering and fruiting stages. Our results showed that the contents of ZR, ABA, and GA exhibited a significant different pattern in normal trees from that in abnormal trees, while the contents of IAA and soluble sugars showed a similar change pattern between them. These results suggest that quantitative changes in endogenous hormones may correspond to different flowering and fruiting mechanisms.

  16. Auxin effectively induces the formation of the secondary abscission zone in Bryophyllum calycinum Salisb. (Crassulaceae)

    OpenAIRE

    Marian Saniewski; Justyna Góraj-Koniarska; Eleonora Gabryszewska; Kensuke Miyamoto; Junichi Ueda

    2016-01-01

    We have found that auxin, indole-3-acetic acid (IAA) substantially induces the formation of the secondary abscission zone in stem and petiole explants and in decapitated stem and petiole after excision of blade in intact plants of Bryophyllum calycinum when IAA at a concentration of 0.1% as lanolin paste was applied in the middle of these organs. The secondary abscission zone was formed at a few mm above of the treatment with IAA, and senescence of the part above abscission zone was observed....

  17. Haloperidol impairs auditory filial imprinting and modulates monoaminergic neurotransmission in an imprinting-relevant forebrain area of the domestic chick.

    Science.gov (United States)

    Gruss, M; Bock, J; Braun, K

    2003-11-01

    In vivo microdialysis and behavioural studies in the domestic chick have shown that glutamatergic as well as monoaminergic neurotransmission in the medio-rostral neostriatum/hyperstriatum ventrale (MNH) is altered after auditory filial imprinting. In the present study, using pharmaco-behavioural and in vivo microdialysis approaches, the role of dopaminergic neurotransmission in this juvenile learning event was further evaluated. The results revealed that: (i) the systemic application of the potent dopamine receptor antagonist haloperidol (7.5 mg/kg) strongly impairs auditory filial imprinting; (ii) systemic haloperidol induces a tetrodotoxin-sensitive increase of extracellular levels of the dopamine metabolite, homovanillic acid, in the MNH, whereas the levels of glutamate, taurine and the serotonin metabolite, 5-hydroxyindole-3-acetic acid, remain unchanged; (iii) haloperidol (0.01, 0.1, 1 mm) infused locally into the MNH increases glutamate, taurine and 5- hydroxyindole-3-acetic acid levels in a dose-dependent manner, whereas homovanillic acid levels remain unchanged; (iv) systemic haloperidol infusion reinforces the N-methyl-d-aspartate receptor-mediated inhibitory modulation of the dopaminergic neurotransmission within the MNH. These results indicate that the modulation of dopaminergic function and its interaction with other neurotransmitter systems in a higher associative forebrain region of the juvenile avian brain displays similar neurochemical characteristics as the adult mammalian prefrontal cortex. Furthermore, we were able to show that the pharmacological manipulation of monoaminergic regulatory mechanisms interferes with learning and memory formation, events which in a similar fashion might occur in young or adult mammals.

  18. Tissue culture and generation of autotetraploid plants of Sophora flavescens Aiton

    Directory of Open Access Journals (Sweden)

    Wei Kun-Hua

    2010-01-01

    Full Text Available Background: Sophora flavescens Aiton is an important medicinal plant in China. Early in vitro researches of S. flavescens were focused on callus induction and cell suspension culture, only a few were concerned with in vitro multiplication. Objective: To establish and optimize the rapid propagation technology of S. flavescens and to generate and characterize polyploid plants of S. flavescens. Materials and Methods: The different concentrations of 6-benzylaminopurine (BAP, indole-3-acetic acid (IAA and kinetin (KT were used to establish and screen the optimal rapid propagation technology of S. flavescens by orthogonal test; 0.2% colchicine solution was used to induce polyploid plants and the induced buds were identified by root-tip chromosome determination and stomatal apparatus observation. Results: A large number of buds could be induced directly from epicotyl and hypocotyl explants on the Murashige and Skoog medium (MS; 1962 supplemented with 1.4-1.6 mg/l 6-benzylaminopurine (BAP and 0.3 mg/l indole-3-acetic acid (IAA. More than 50 lines of autotetraploid plants were obtained. The chromosome number of the autotetraploid plantlet was 2n = 4x = 36. All tetraploid plants showed typical polyploid characteristics. Conclusion: Obtained autotetraploid lines will be of important genetic and breeding value and can be used for further selection and plant breeding.

  19. Anticoccidial effects of acetic acid on performance and pathogenic parameters in broiler chickens challenged with Eimeria tenella

    Directory of Open Access Journals (Sweden)

    Rao Z. Abbas

    2011-02-01

    Full Text Available The objective of the present study was to evaluate the anticoccidial effect of the different concentrations of the acetic acid in the broiler chickens in comparison with the amprolium anticoccidial. A total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations (1%, 2% and 3% of acetic acid and amproilum (at the dose rate of 125ppm were given to the experimental groups in drinking water from 10-19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. All the groups were inoculated orally with 75,000 sporulated oocysts at the 12th day of age except non infected non medicated control. Anticoccidial effect was evaluated on the basis of performance (weight gain, feed conversion ratio and pathogenic (oocyst score, lesion score and mortality %age parameters. Among acetic acid medicated groups, the maximum anticoccidial effect was seen in the group medicated with 3% acetic acid followed by 2% and 1% acetic acid medicated groups. Amprolium and 3% acetic acid were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella challenge. In summary, acetic acid has the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. Concentration-dependent anticoccidial effect of acetic acid suggests that further studies should be carried out to determine the possible maximum safe levels of acetic acid with least toxic effects to be used as anticoccidial.

  20. Oligogalacturonide-auxin antagonism does not require posttranscriptional gene silencing or stabilization of auxin response repressors in Arabidopsis.

    Science.gov (United States)

    Savatin, Daniel V; Ferrari, Simone; Sicilia, Francesca; De Lorenzo, Giulia

    2011-11-01

    α-1-4-Linked oligogalacturonides (OGs) derived from plant cell walls are a class of damage-associated molecular patterns and well-known elicitors of the plant immune response. Early transcript changes induced by OGs largely overlap those induced by flg22, a peptide derived from bacterial flagellin, a well-characterized microbe-associated molecular pattern, although responses diverge over time. OGs also regulate growth and development of plant cells and organs, due to an auxin-antagonistic activity. The molecular basis of this antagonism is still unknown. Here we show that, in Arabidopsis (Arabidopsis thaliana), OGs inhibit adventitious root formation induced by auxin in leaf explants as well as the expression of several auxin-responsive genes. Genetic, biochemical, and pharmacological experiments indicate that inhibition of auxin responses by OGs does not require ethylene, jasmonic acid, and salicylic acid signaling and is independent of RESPIRATORY BURST OXIDASE HOMOLOGUE D-mediated reactive oxygen species production. Free indole-3-acetic acid levels are not noticeably altered by OGs. Notably, OG- as well as flg22-auxin antagonism does not involve any of the following mechanisms: (1) stabilization of auxin-response repressors; (2) decreased levels of auxin receptor transcripts through the action of microRNAs. Our results suggest that OGs and flg22 antagonize auxin responses independently of Aux/Indole-3-Acetic Acid repressor stabilization and of posttranscriptional gene silencing.

  1. Efficient plant regeneration of bittersweet (Solanum dulcamara L., a medicinal plant

    Directory of Open Access Journals (Sweden)

    Arzu Ucar Turker

    2011-04-01

    Full Text Available Solanum dulcamara L. (bittersweet is a medicinal plant that has been used to treat skin diseases, warts, tumors, felons, arthritis, rheumatism, bronchial congestion, heart ailments, ulcerative colitis, eye inflammations, jaundice and pneumonia. A reliable in vitro culture protocol for bittersweet was established. Explants (leaf and petiole segments were cultured on Murashige and Skoog minimal organics (MSMO medium with various plant growth regulator combinations. Leaf explants formed more shoots than petiole explants. Plant regeneration was observed through indirect organogenesis with both explants. Best shoot proliferation was obtained from leaf explants with 3 mg/l BA (benzyladenine and 0.5 mg/l IAA (indole-3-acetic acid. Regenerated shoots were transferred to rooting media containing different levels of IAA (indole-3-acetic acid, IBA (indole-3-butyric acid, NAA (naphthalene acetic acid or 2,4-D (2,4 dichlorophenoxyacetic acid. Most shoots developed roots on medium with 0.5 mg/l IBA. Rooted explants were transferred to vermiculate in Magenta containers for acclimatization and after 2 weeks, they were planted in plastic pots containing potting soil and maintained in the plant growth room.

  2. Evaluation of Short-Term and Long-Term Migration Testing from Can Coatings into Food Simulants: Epoxy and Acrylic-Phenolic Coatings.

    Science.gov (United States)

    Paseiro-Cerrato, Rafael; DeVries, Jonathan; Begley, Timothy H

    2017-03-29

    Traditionally, migration testing during 10 days at 40 °C has been considered sufficient and appropriate for simulating the potential migration of substances from food-contact materials into foods. However, some packages, such as food cans, may be stored holding food for extended time periods (years). This study attempts to verify whether common testing conditions accurately estimate long-term migration. Two types of can coatings, epoxy and acrylic-phenolic, were subjected to short-term and long-term migration testing (1 day-1.5 years) using food simulants (water, 3% acetic acid, 50% ethanol, and isooctane) at 40 °C. Using HPLC-DAD/CAD, HPLC-MS, UHPLC-HRMS (where HRMS is accurate mass, mass spectrometry), and DART-HRMS, we identified potential migrants before starting the experiment: BPA, BADGE, BADGE derivatives, benzoguanamine, and other relevant marker compounds. During the experiment using a water-based food simulant, migrants remained stable. Most of the cans in contact with 3% acetic acid did not survive the experimental conditions. Tracked migrants were not detected in isooctane. In the presence of 50% ethanol, the traditional migration test during 10 days at 40 °C did not predict migration during long-term storage. These results suggest that migration protocols should be modified to account for long-term storage.

  3. A proteomics study of auxin effects in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Meiqing Xing; Hongwei Xue

    2012-01-01

    Many phytohormones regulate plant growth and development through modulating protein degradation.In this study,a proteome study based on multidimensional non-gel shotgun approach was performed to analyze the auxin-induced protein degradation via ubiquitinproteasome pathway of Arabidopsis thaliana,with the emphasis to study the overall protein changes after auxin treatment (1 nM or 1 μM indole-3-acetic acid for 6,12,or 24 h).More than a thousand proteins were detected by using label-free shotgun method,and 386 increased proteins and 370 decreased ones were identified after indole-3-acetic acid treatment.By using the auxin receptor-deficient mutant,tir1-1,as control,comparative analysis revealed that 69 and 79 proteins were significantly decreased and increased,respectively.Detailed analysis showed that among the altered proteins,some were previously reported to be associated with auxin regulation and others are potentially involved in mediating the auxin effects on specific cellular and physiological processes by regulating photosynthesis,chloroplast development,cytoskeleton,and intracellular signaling.Our results demonstrated that label-free shotgun proteomics is a powerful tool for large-scale protein identification and the analysis of the proteomic profiling of auxin-regulated biological processes will provide informative clues of underlying mechanisms of auxin effects.These results will help to expand the understanding of how auxin regulates plant growth and development via protein degradation.

  4. Morphogenetic Potential of Tomato (Lycopersicon esculentum cv. ‘Arka Ahuti’ to Plant Growth Regulators

    Directory of Open Access Journals (Sweden)

    Kanakapura K. NAMITHA

    2013-05-01

    Full Text Available A highly reproducible in vitro regeneration method for tomato (Lycopersicon esculentum Mill. cultivar ‘Arka Ahuti’ was established by using hypocotyl, leaf and cotyledon explants from in vitro raised seedlings on Murashige and Skoog medium supplemented with different concentrations and combinations of hormones 6-Benzylamino purine (2 to 4 mg/L and Indole-3-acetic acid (0.1 to 1 mg/L. The medium supplemented with 2 mg/L 6-benzylamino purine and 0.1 mg/L indole-3-acetic acid was found to be the best for inducing direct shoot regeneration and multiple shoots per explant from hypocotyl explants. Callus induction was observed in all the explants and regeneration of shoots was also promoted by all these combinations. Shoots were transferred to the elongation medium which also induced 100% rooting. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established for ‘Arka Ahuti’ cultivar of tomato for obtaining direct regeneration using hypocotyl, leaf and cotyledon as explants.

  5. Gravitational effects on plant growth hormone concentration

    Science.gov (United States)

    Bandurski, Robert S.; Schulze, Aga

    Numerous studies, particularly those of H. Dolk in the 1930's, established by means of bio-assay, that more growth hormone diffused from the lower, than from the upper side of a gravity-stimulated plant shoot. Now, using an isotope dilution assay, with 4,5,6,7 tetradeutero indole-3-acetic acid as internal standard, and selected ion monitoring-gas chromatography-mass spectrometry as the method of determination, we have confirmed Dolk's finding and established that the asymmetrically distributed hormone is, in fact, indole-3-acetic acid (IAA). This is the first physico-chemical demonstration that there is more free IAA on the lower sides of a geo-stimulated plant shoot. We have also shown that free IAA occurs primarily in the conductive vascular tissues of the shoot, whereas IAA esters predominate in the growing cortical cells. Now, using an especially sensitive gas chromatographic isotope dilution assay we have found that the hormone asymmetry also occurs in the non-vascular tissue. Currently, efforts are directed to developing isotope dilution assays, with picogram sensitivity, to determine how this asymmetry of IAA distribution is attained so as to better understand how the plant perceives the geo-stimulus.

  6. Bioactivity-guided study of antiproliferative activities of Salvia extracts.

    Science.gov (United States)

    Janicsák, Gábor; Zupkó, István; Nikolovac, Milena T; Forgo, Peter; Vasas, Andrea; Mathé, Imre; Blunden, Gerald; Hohmann, Judit

    2011-05-01

    The cytotoxic activities of the n-hexane, chloroform and aqueous methanolic fractions prepared from the methanolic extract of the leaves of 23 Salvia taxa were studied for their cell growth-inhibitory activity against human cervix adenocarcinoma (HeLa), skin carcinoma (A431) and breast adenocarcinoma (MCF7) cells using the MTT assay. The n-hexane fractions of six Salvia taxa (S. hispanica, S. nemorosa, S. nemorosa 1. albiflora, S. pratensis, S. recognita and S. ringens) and the chloroform fraction ofS. officinalis 1. albiflora produced over 50% growth inhibition of the skin carcinoma cell line. None of the tested extracts showed substantial (above 50%) antiproliferative effects against HeLa and MCF7 cells. S. ringens was the most powerful among the studied Salvia species with a 61.8% cell growth inhibitory activity on A431 cells. In the case of S. ringens, other plant parts were also tested for antiproliferative effect, and the highest activities were recorded for the root extract. This was subjected to bioactivity-guided fractionation, which yielded four abietane diterpenes (royleanone, horminone, 7-O-methyl-horminone and 7-acetyl-horminone), one triterpene (erythrodiol-3-acetate) and beta-sitosterol. Horminone, 7-acetyl-horminone and erythrodiol-3-acetate displayed marked concentration-dependent antiproliferative effects, while royleanone and 7-O-methyl-horminone produced weaker activities.

  7. Growth, Morphology and Growth Related Hormone Level in Kappaphycus alvarezii Produced by Mass Selection in Gorontalo Waters, Indonesia

    Directory of Open Access Journals (Sweden)

    Siti Fadilah

    2016-01-01

    Full Text Available The use of high quality seed can support the success of the seaweed cultivation. This study was conducted to evaluate the growth performance, morphology and growth related hormone level of brown strain seaweed Kappaphycus alvarezii seed produced by mass selection. Selection was performed in the Tomini Gulf, Gorontalo, based on mass selection of seaweed seed protocol with a slight modification in cut-off 10% of the highest daily growth rate. Selection was carried out for four generations. The selected 4th generation of seed was then used in cultivation performance test in the Celebes Sea, North Gorontalo, for three production cycles. The results showed that the selected K. alvarezii has higher clump weight and daily growth rate, longer thallus, more number of branches, and shorter internodes compared to the unselected control and seaweed from the farmer as external control. Furthermore, total sugar content, levels of kinetin hormone and kinetin:indole-3-acetic acid ratio were higher in selected seaweeds than that of unselected control and external control. Thus, mass selection method could be used to produce high growth of seed, and kinetin and indole-3-acetic acid play an important role in growth of K. alvarezii.

  8. Mycorrhizal trifoliate orange has greater root adaptation of morphology and phytohormones in response to drought stress

    Science.gov (United States)

    Zou, Ying-Ning; Wang, Peng; Liu, Chun-Yan; Ni, Qiu-Dan; Zhang, De-Jian; Wu, Qiang-Sheng

    2017-01-01

    Plant roots are the first parts of plants to face drought stress (DS), and thus root modification is important for plants to adapt to drought. We hypothesized that the roots of arbuscular mycorrhizal (AM) plants exhibit better adaptation in terms of morphology and phytohormones under DS. Trifoliate orange seedlings inoculated with Diversispora versiformis were subjected to well-watered (WW) and DS conditions for 6 weeks. AM seedlings exhibited better growth performance and significantly greater number of 1st, 2nd, and 3rd order lateral roots, root length, area, average diameter, volume, tips, forks, and crossings than non-AM seedlings under both WW and DS conditions. AM fungal inoculation considerably increased root hair density under both WW and DS and root hair length under DS, while dramatically decreased root hair length under WW but there was no change in root hair diameter. AM plants had greater concentrations of indole-3-acetic acid, methyl jasmonate, nitric oxide, and calmodulin in roots, which were significantly correlated with changes in root morphology. These results support the hypothesis that AM plants show superior adaptation in root morphology under DS that is potentially associated with indole-3-acetic acid, methyl jasmonate, nitric oxide, and calmodulin levels. PMID:28106141

  9. Asymmetric distribution of glucose and indole-3-acetyl-myo-inositol in geostimulated Zea mays seedlings

    Science.gov (United States)

    Momonoki, Y. S.; Bandurski, R. S. (Principal Investigator)

    1988-01-01

    Indole-3-acetyl-myo-inositol occurs in both the kernel and vegetative shoot of germinating Zea mays seedlings. The effect of a gravitational stimulus on the transport of [3H]-5-indole-3-acetyl-myo-inositol and [U-14C]-D-glucose from the kernel to the seedling shoot was studied. Both labeled glucose and labeled indole-3-acetyl-myo-inositol become asymmetrically distributed in the mesocotyl cortex of the shoot with more radioactivity occurring in the bottom half of a horizontally placed seedling. Asymmetric distribution of [3H]indole-3-acetic acid, derived from the applied [3H]indole-3-acetyl-myo-inositol, occurred more rapidly than distribution of total 3H-radioactivity. These findings demonstrate that the gravitational stimulus can induce an asymmetric distribution of substances being transported from kernel to shoot. They also indicate that, in addition to the transport asymmetry, gravity affects the steady state amount of indole-3-acetic acid derived from indole-3-acetyl-myo-inositol.

  10. Quantification of polyacetylenes in apiaceous plants by high-performance liquid chromatography coupled with diode array detection.

    Science.gov (United States)

    Kramer, Maike; Mühleis, Andrea; Conrad, Jürgen; Leitenberger, Martin; Beifuss, Uwe; Carle, Reinhold; Kammerer, Dietmar R

    2011-01-01

    Polyacetylenes are known for their biofunctional properties in a wide range of organisms. In the present study, the most frequently occurring polyacetylenes, i.e. falcarinol, falcarindiol, and falcarindiol-3-acetate, were determined in six genera of the Apiaceae family. For this purpose, a straightforward and reliable method for the screening and quantification of the polyacetylenes using high-performance liquid chromatography coupled with diode array and mass spectrometric detection without tedious sample clean-up has been developed. Peak assignment was based on retention times, UV spectra, and mass spectral data. Quantification was carried out using calibration curves of authentic standards isolated from turnip-rooted parsley and Ligusticum mutellina, respectively. The references were unambiguously identified by Fourier transform-IR (FT-IR) spectroscopy, GC-MS, HPLC-MSn in the positive ionization mode, and 1H NMR and 13C NMR spectroscopy. To the best of our knowledge, the occurrence of falcarindiol-3-acetate in Anthriscus sylvestris and Pastinaca sativa has been reported for the first time. The data revealed great differences in the polyacetylene contents and varying proportions of individual compounds in the storage roots of Apiaceous plants. The results of the present study may be used as a suitable tool for authenticity control and applied to identify novel sources devoid or particularly rich in polyacetylenes, thus facilitating breeding programs for the selective enrichment and depletion of these plant secondary metabolites, respectively.

  11. Dietary polyacetylenes of the falcarinol type are inhibitors of breast cancer resistance protein (BCRP/ABCG2).

    Science.gov (United States)

    Tan, Kee W; Killeen, Daniel P; Li, Yan; Paxton, James W; Birch, Nigel P; Scheepens, Arjan

    2014-01-15

    Polyacetylenes of the falcarinol type are present in vegetables such as carrots and parsley. They display interesting bioactivities and hold potential as health-promoting and therapeutic agents. In this study, falcarinol, falcarindiol, falcarindiol 3-acetate and falcarindiol 3,8-diacetate were examined for their modulation on breast cancer resistance protein (BCRP/ABCG2), an efflux transporter important for xenobiotic absorption and disposition, and multidrug resistance in cancer. Falcarinol, falcarindiol, and falcarindiol 3-acetate were extracted from carrots and falcarindiol 3,8-diacetate prepared from falcarindiol. Their modulatory effects on ABCG2 were studied using three methods-mitoxantrone accumulation, vesicular transport, and ATPase assay. The polyacetylenes inhibited mitoxantrone (an ABCG2 substrate) efflux in ABCG2-overexpressing HEK293 cells. The inhibitory effect was confirmed in the vesicular transport assay, in which concentration-dependent inhibition of methotrexate (an ABCG2 substrate) uptake into ABCG2-overexpressing Sf9 membrane vesicles was observed (IC50=19.7-41.7µM). The polyacetylenes also inhibited baseline and sulfasalazine-stimulated vanadate-sensitive ATPase activities in ABCG2-overexpressing Sf9 membrane vesicles (IC50=19.3-79.3µM). This is the first report of an inhibitory effect of polyacetylenes on ABCG2. These results indicate a prospective use of polyacetylenes as multidrug resistance reversal agents, a possible role of ABCG2 in the absorption and disposition of polyacetylenes, and potential food-drug interactions between polyacetylene-rich foods and ABCG2 substrate drugs.

  12. Comparison of polyacetylene content in organically and conventionally grown carrots using a fast ultrasonic liquid extraction method.

    Science.gov (United States)

    Søltoft, Malene; Eriksen, Morten Rosbjørn; Träger, Anne Wibe Braendholt; Nielsen, John; Laursen, Kristian Holst; Husted, Søren; Halekoh, Ulrich; Knuthsen, Pia

    2010-07-14

    A rapid and sensitive analytical method for quantification of polyacetylenes in carrot roots was developed. The traditional extraction method (stirring) was compared to a new ultrasonic liquid processor (ULP)-based methodology using high-performance liquid chromatography-ultraviolet (HPLC-UV) and mass spectrometry (MS) for identification and quantification of three polyacetylenes. ULP was superior because a significant reduction in extraction time and improved extraction efficiencies were obtained. After optimization, the ULP method showed good selectivity, precision [relative standard deviations (RSDs) of 2.3-3.6%], and recovery (93% of falcarindiol) of the polyacetylenes. The applicability of the method was documented by comparative analyses of carrots grown organically or conventionally in a 2 year field trial study. The average concentrations of falcarindiol, falcarindiol-3-acetate, and falcarinol in year 1 were 222, 30, and 94 mug of falcarindiol equiv/g of dry weight, respectively, and 3-15% lower in year 2. The concentrations were not significantly influenced by the growth system, but a significant year-year variation was observed for falcarindiol-3-acetate.

  13. Functional characterization of PaLAX1, a putative auxin permease, in heterologous plant systems.

    Science.gov (United States)

    Hoyerová, Klára; Perry, Lucie; Hand, Paul; Lanková, Martina; Kocábek, Tomás; May, Sean; Kottová, Jana; Paces, Jan; Napier, Richard; Zazímalová, Eva

    2008-03-01

    We have isolated the cDNA of the gene PaLAX1 from a wild cherry tree (Prunus avium). The gene and its product are highly similar in sequences to both the cDNAs and the corresponding protein products of AUX/LAX-type genes, coding for putative auxin influx carriers. We have prepared and characterized transformed Nicotiana tabacum and Arabidopsis thaliana plants carrying the gene PaLAX1. We have proved that constitutive overexpression of PaLAX1 is accompanied by changes in the content and distribution of free indole-3-acetic acid, the major endogenous auxin. The increase in free indole-3-acetic acid content in transgenic plants resulted in various phenotype changes, typical for the auxin-overproducing plants. The uptake of synthetic auxin, 2,4-dichlorophenoxyacetic acid, was 3 times higher in transgenic lines compared to the wild-type lines and the treatment with the auxin uptake inhibitor 1-naphthoxyacetic acid reverted the changes caused by the expression of PaLAX1. Moreover, the agravitropic response could be restored by expression of PaLAX1 in the mutant aux1 plants, which are deficient in auxin influx carrier activity. Based on our data, we have concluded that the product of the gene PaLAX1 promotes the uptake of auxin into cells, and, as a putative auxin influx carrier, it affects the content and distribution of free endogenous auxin in transgenic plants.

  14. Functional Characterization of PaLAX1, a Putative Auxin Permease, in Heterologous Plant Systems1[W][OA

    Science.gov (United States)

    Hoyerová, Klára; Perry, Lucie; Hand, Paul; Laňková, Martina; Kocábek, Tomáš; May, Sean; Kottová, Jana; Pačes, Jan; Napier, Richard; Zažímalová, Eva

    2008-01-01

    We have isolated the cDNA of the gene PaLAX1 from a wild cherry tree (Prunus avium). The gene and its product are highly similar in sequences to both the cDNAs and the corresponding protein products of AUX/LAX-type genes, coding for putative auxin influx carriers. We have prepared and characterized transformed Nicotiana tabacum and Arabidopsis thaliana plants carrying the gene PaLAX1. We have proved that constitutive overexpression of PaLAX1 is accompanied by changes in the content and distribution of free indole-3-acetic acid, the major endogenous auxin. The increase in free indole-3-acetic acid content in transgenic plants resulted in various phenotype changes, typical for the auxin-overproducing plants. The uptake of synthetic auxin, 2,4-dichlorophenoxyacetic acid, was 3 times higher in transgenic lines compared to the wild-type lines and the treatment with the auxin uptake inhibitor 1-naphthoxyacetic acid reverted the changes caused by the expression of PaLAX1. Moreover, the agravitropic response could be restored by expression of PaLAX1 in the mutant aux1 plants, which are deficient in auxin influx carrier activity. Based on our data, we have concluded that the product of the gene PaLAX1 promotes the uptake of auxin into cells, and, as a putative auxin influx carrier, it affects the content and distribution of free endogenous auxin in transgenic plants. PMID:18184737

  15. Characteristics of triphenylamine-based dyes with multiple acceptors in application of dye-sensitized solar cells

    Science.gov (United States)

    Yang, Chien-Hsin; Chen, Han-Lung; Chuang, Yao-Yuan; Wu, Chun-Guey; Chen, Chiao-Pei; Liao, Shao-Hong; Wang, Tzong-Liu

    We report the synthesis and photophysical/electrochemical properties of triphenylamine (TPA)-based multiple electron acceptor dyes (TPAR1, TPAR2, and TPAR3) as well as their applications in dye-sensitized solar cells (DSSCs). In these dyes, the TPA group and the rhodanine-3-acetic acid play the role of the basic electron donor unit and the electron acceptor, respectively. It was found that introduction of two rhodanine-3-acetic acid groups into the TPA unit (TPAR2) exhibited better photovoltaic performance due to the increase with a red shift and broadening of the absorption spectrum. The monolayer of these TPA-based dyes was adsorbed on the surface of nanocrystalline TiO 2 mesoporous electrode with the thickness of ∼6 μm, polyethylene oxide (PEO) used as the matrix of gel electrolyte, and 4-nm thick Pt used as a counter-electrode. Photovoltaic device can be realized in a single quasi-solid-state DSSC. TPAR2-based gel DSSC had an open circuit voltage and short circuit current density of about 541 and 10.7 mA cm -2, respectively, at 1-sun.

  16. A carotenoid-deficient mutant in Pantoea sp. YR343, a bacteria isolated from the rhizosphere of Populus deltoides, is defective in root colonization

    Directory of Open Access Journals (Sweden)

    Amber N Bible

    2016-04-01

    Full Text Available The complex interactions between plants and their microbiome can have a profound effect on the health and productivity of the plant host. A better understanding of the microbial mechanisms that promote plant health and stress tolerance will enable strategies for improving the productivity of economically-important plants. Pantoea sp. YR343 is a motile, rod-shaped bacterium isolated from the roots of Populus deltoides that possesses the ability to solubilize phosphate and produce the phytohormone indole-3-acetic acid. Pantoea sp. YR343 readily colonizes plant roots and does not appear to be pathogenic when applied to the leaves or roots of selected plant hosts. To better understand the molecular mechanisms involved in plant association and rhizosphere survival by Pantoea sp. YR343, we constructed a mutant in which the crtB gene encoding phytoene synthase was deleted. Phytoene synthase is responsible for converting geranylgeranyl pyrophosphate to phytoene, an important precursor to the production of carotenoids. As predicted, the ΔcrtB mutant is defective in carotenoid production, and shows increased sensitivity to oxidative stress. Moreover, we find that the ΔcrtB mutant is impaired in biofilm formation and production of indole-3-acetic acid. Finally we demonstrate that the ΔcrtB mutant shows reduced colonization of plant roots. Taken together, these data suggest that carotenoids are important for plant association and/or rhizosphere survival in Pantoea sp. YR343.

  17. Membrane effects of 2,4-dichlorophenoxyacetic acid in motor cells of Mimosa pudica L.

    Science.gov (United States)

    Moyen, Christelle; Bonmort, Janine; Roblin, Gabriel

    2007-01-01

    2,4-dichlorophenoxyacetic acid applied to excised leaves of Mimosa pudica L. inhibited in a dose-dependent manner the shock-induced pulvinar movement. This inhibition was negatively correlated with the amount of [(14)C] 2,4-dichlorophenoxyacetic acid present in the vicinity of the motor cells. Although 2,4-dichlorophenoxyacetic acid is a weak acid, its greatest physiological efficiency was obtained with pH values close to neutrality. This observation opens the question of its mode of action which may be through external signaling or following internal transport by a specific anionic form transporter. The effect was related to molecular structure since 2,4-dichlorophenoxyacetic acid>3,4-dichlorophenoxyacetic acid>2,3-dichlorophenoxyacetic acid. An essential target of 2,4-dichlorophenoxyacetic acid action lies at the plasmalemma as indicated by the induced hyperpolarization of the cell membrane. Compared to indole-3-acetic acid and fusicoccin, it induced a complex effect on H(+) fluxes. Applied to plasma membrane vesicles purified from motor organs, 2,4-dichlorophenoxyacetic acid enhanced proton pumping, but, unlike fusicoccin, it did not increase the H(+)-ATPase catalytic activity in our experimental conditions. Taken together, the data suggest that 2,4-dichlorophenoxyacetic acid acts on cell turgor variation and the concomittant ion migration, in particular K(+), by a mechanism involving specific steps compared to indole-3-acetic acid and fusicoccin.

  18. Indirect organogenesis from various explants of Hildegardia populifolia (Roxb. Schott & Endl. – A threatened tree species from Eastern Ghats of Tamil Nadu, India

    Directory of Open Access Journals (Sweden)

    A.R. Lavanya

    2014-12-01

    Full Text Available Hildegardia species are an important resource for fiber industry. This investigation was conducted to develop a plant regeneration protocol for Hildegardia populifolia (Roxb. Schott & Endl. via indirect organogenesis Callus was obtained from leaf, internode and petiole explants, among these explants internode explant gave best result on MS medium supplemented with different concentrations of 2,4-Dichlorophenoxy acetic acid (2,4-D. The highest percentage (100% of regeneration was obtained with benzyladenine (BA (2.0 mg/l + indole-3-acetic acid (IAA (0.1 mg/l + glutamine (25 mg/l + thidiazuron (TDZ (0.5 mg/l from internode explants. Shootlets were highly rooted on MS medium supplemented with 3.0 mg/l indole-3-butyric acid (IBA. In vitro rooted seedlings were successfully acclimatized. This in vitro regeneration system will facilitate further development of reliable procedures for this genus.

  19. Relationship between gene responses and symptoms induced by Rice grassy stunt virus

    Directory of Open Access Journals (Sweden)

    Kouji eSatoh

    2013-10-01

    Full Text Available Rice grassy stunt virus (RGSV is a serious threat to rice production in Southeast Asia. RGSV is a member of the genus Tenuivirus, and it induces leaf yellowing, stunting, and excess tillering on rice plants. Here we examined gene responses of rice to RGSV infection to gain insight into the gene responses which might be associated with the disease symptoms. The results indicated that 1 many genes related to cell wall synthesis and chlorophyll synthesis were predominantly suppressed by RGSV infection; 2 RGSV infection induced genes associated with tillering process; 3 RGSV activated genes involved in inactivation of gibberellic acid and indole-3-acetic acid ; and 4 the genes for strigolactone signaling were suppressed by RGSV. These results suggest that these gene responses to RGSV infection account for the excess tillering specific to RGSV infection as well as other symptoms by RGSV, such as stunting and leaf chlorosis.

  20. In vitro micropropagation of Stevia rebaudiana Bertoni in Malaysia

    Directory of Open Access Journals (Sweden)

    Ummi Nur Ain Abdul Razak

    2014-02-01

    Full Text Available Stevia rebaudiana Bertoni is a medicinal plants and commercially use as non-caloric sweetener for diabetic patient. In the present study, a protocol was developed for in vitro micropropagation using 6-benzylamino purine (BAP and Kinetin (Kn for the formation of multiple shoot proliferation and Indole-3-acetic acid (IAA, Indole-3-butyric acid (IBA and 1-Naphthaleneacetic acid (NAA for the induction of roots. Maximum shoot formation (7.82 ± 0.7 shoots per explants was observed on a Murashige and Skoog (MS medium supplemented with 0.5 mg L-1 BAP and 0.25 mg L-1 Kn. The maximum number of roots (30.12 ± 2.1 roots per explants was obtained on a MS medium containing 1.0 mg L-1 IBA. The well rooted plantlets were successfully weaned and acclimatized in plant soil with survival rate of 83.3 %.

  1. Effects of plant growth regulators on the growth and lipid accumulation of Nannochloropsis oculata (droop) Hibberd

    Science.gov (United States)

    Trinh, Cam Tu; Tran, Thanh Huong; Bui, Trang Viet

    2017-09-01

    Nannochloropsis oculata cells were grown in f/2 modified medium of Chiu et al. (2009) supplemented with the plant growth regulators in different concentrations. Lipid accumulation of N. oculata cells was evaluated by using Nile Red dye and Fiji Image J with Analyze Particles. Indole-3-acetic acid (IAA) stimulated the increase of cell density in rapid growth phase (day 6) at high concentration (0.75 mg/L) and in slow growth phase (day 10) at lower concentration (0.50 mg/L). IAA, gibberellic acid (GA3) and zeatin increased content of chlorophyll a, in particular, in f/2 modified medium supplemented with 0.5 mg/L zeatin at the 10th day of culture. Roles of plant growth regulators in growth and lipid accumulation of N. oculata were discussed.

  2. Plant regeneration from protoplasts of hydroxyproline resistant cell line in Onobrychis viciaefolia

    Institute of Scientific and Technical Information of China (English)

    XUZIQIN; JINGFENJIA

    1995-01-01

    An efficient protocol for plant regeneration from protoplasts of hydroxyproline(HYP)resistant cell line of Onobrychis viciaefolia was established.In SH medium supplemented with 1mg/L2,4-dichlorophenoxy-acetic acid(2,4-D),0.5mg/L kinetin(KT)and 0.2mg/L naphthalene acetic acid(NAA),the division frequency of protoplastderived cells reached up to over 60%,and microcalli were obtained in 5-6wk.Upon transferring them on agar solidified MS medium plus 2mg/L indole-3-acetic acid (IAA),shoots were induced.After cultivating them on MS medium with or without IAA,roots were regenerated.Chromosome number of all protoplast-regenerated plants examined were normal(2n=28).The protoplast-derived calli and plants grew vigorously on the medium containing 10 mmol/L HYP.

  3. Gravimetric method for the determination of diclofenac in pharmaceutical preparations.

    Science.gov (United States)

    Tubino, Matthieu; De Souza, Rafael L

    2005-01-01

    A gravimetric method for the determination of diclofenac in pharmaceutical preparations was developed. Diclofenac is precipitated from aqueous solution with copper(II) acetate in pH 5.3 (acetic acid/acetate buffer). Sample aliquots had approximately the same quantity of the drug content in tablets (50 mg) or in ampules (75 mg). The observed standard deviation was about +/- 2 mg; therefore, the relative standard deviation (RSD) was approximately 4% for tablet and 3% for ampule preparations. The results were compared with those obtained with the liquid chromatography method recommended in the United States Pharmacopoeia using the statistical Student's t-test. Complete agreement was observed. It is possible to obtain more precise results using higher aliquots, for example 200 mg, in which case the RSD falls to 1%. This gravimetric method, contrary to what is expected for this kind of procedure, is relatively fast and simple to perform. The main advantage is the absolute character of the gravimetric analysis.

  4. Altered phenotypes in plants transformed with chimeric tobacco peroxidase genes

    Energy Technology Data Exchange (ETDEWEB)

    Lagrimini, L.M.

    1990-12-31

    Peroxidases have been implicated in a variety of secondary metabolic reactions including lignification, cross-linking of cell wall polysaccharides, oxidation of indole-3-acetic acid, regulation of cell elongation, wound-healing, phenol oxidation, and pathogen defense. However, due to the many different isoenzymes and even more potential substrates, it has proven difficult to verify actual physiological roles for peroxidase. We are studying the molecular biology of the tobacco peroxidase genes, and have utilized genetic engineering techniques to produce transgenic plants which differ only in their expression of an individual peroxidase isoenzyme. Many of the in planta functions for any individual isoenzyme may be predicted through the morphological and physiological analysis of transformed plants.

  5. Altered phenotypes in plants transformed with chimeric tobacco peroxidase genes

    Energy Technology Data Exchange (ETDEWEB)

    Lagrimini, L.M.

    1990-01-01

    Peroxidases have been implicated in a variety of secondary metabolic reactions including lignification, cross-linking of cell wall polysaccharides, oxidation of indole-3-acetic acid, regulation of cell elongation, wound-healing, phenol oxidation, and pathogen defense. However, due to the many different isoenzymes and even more potential substrates, it has proven difficult to verify actual physiological roles for peroxidase. We are studying the molecular biology of the tobacco peroxidase genes, and have utilized genetic engineering techniques to produce transgenic plants which differ only in their expression of an individual peroxidase isoenzyme. Many of the in planta functions for any individual isoenzyme may be predicted through the morphological and physiological analysis of transformed plants.

  6. Influence of microbial diversity and plant growth hormones in compost and vermicompost from fermented tannery waste.

    Science.gov (United States)

    Ravindran, Balasubramani; Wong, Jonathan W C; Selvam, Ammaiyappan; Sekaran, Ganesan

    2016-10-01

    This study focuses on the effect of the epigeic earthworm Eudrilus eugeniae (with and without addition) to transform solid state fermented (SSF) and submerged (SmF) state fermented TFL mixed with cow dung and leaf litter into value added products in compost and vermicompost bioreactors respectively. The significant role of microbes was identified during compost and vermicompost process. In addition, three important phytohormones (Indole 3-acetic acid, Gibberellic acid, Kinetin) were also detected in the compost and vermicompost products. The results revealed that the maximum amount of plant hormones were available in the vermicompost products which may be due to the joint action of earthworm and microorganisms. The overall results confirmed that the vermicomposting process produced a greater value added product.

  7. Detection and quantification of some plant growth regulators in a seaweed-based foliar spray employing a mass spectrometric technique sans chromatographic separation.

    Science.gov (United States)

    Prasad, Kamalesh; Das, Arun Kumar; Oza, Mihir Deepak; Brahmbhatt, Harshad; Siddhanta, Arup Kumar; Meena, Ramavatar; Eswaran, Karuppanan; Rajyaguru, Mahesh Rameshchandra; Ghosh, Pushpito Kumar

    2010-04-28

    The sap expelled from the fresh harvest of Kappaphycus alvarezii , a red seaweed growing in tropical waters, has been reported to be a potent foliar spray. Tandem mass spectrometry of various organic extracts of the sap confirmed the presence of the plant growth regulators (PGRs) indole 3-acetic acid, gibberellin GA(3), kinetin, and zeatin. These PGRs were quantified in fresh state and after 1 year of storage by ESI-MS without recourse to chromatographic separation. Quantification was validated against HPLC data. The results may be useful in correlating with the efficacy of the sap. The methodology was extended to two other seaweeds. The method developed is convenient and precise and may find application in other agricultural formulations containing these growth hormones.

  8. Vegetative propagation of Aesculus indica through stem cuttings treated with plant growth regulators

    Institute of Scientific and Technical Information of China (English)

    Mumtaz Majeed; M.A.Khan; A.H.Mughal

    2009-01-01

    Cuttage propagation of Aesculus indica was tested by treatments with different concentrations of indole-3-acetic acid (IAA) @ 2000, 4000 (ppm), indolebutyric acid (IBA) @ 2000, 4000 (ppm) and naphthlcetic acid (NAA) @ 2000, 4000 (ppm) in dry formulation in the Forest Nursery, Faculty of Forestry, SKUAST-K, Shalimar. The cuttings treated with IBA @ 4000 ppm and IBA @ 2000 ppm had a sprouting rate of 75% and 50%, respectively, which was significantly higher than that of control and other treatments. The highest rooting rate (50%) was recorded in the cuttings with the application of IBA @ 4000 ppm. The cuttings treated with IBA @ 2000 ppm had 25% rooting rate. All other treatments along with control (talc powder) failed to induce rooting. It was concluded that IBA @ 4000 ppm was a better-applied concentration for vegetative propagation of A. indica under Kashmir conditions.

  9. Occurrence of plant growth regulators in Psilotum nudum.

    Science.gov (United States)

    Abul, Y; Menéndez, V; Gómez-Campo, C; Revilla, M A; Lafont, F; Fernández, H

    2010-09-15

    The endogenous content of the auxin indole-3-acetic acid (IAA), the cytokinins trans-zeatin (tZ), trans-zeatin riboside (tZR), dihydrozeatin (DHZ), dihydrozeatin riboside (DHZR), isopentenyladenine (iP) and isopentenyladenosine (iPR), the gibberellins GA(1), GA(3), GA(4), GA(7), GA(9) and GA(20) in the rhizome and aerial shoots during and after sporogenesis were measured by high-performance liquid chromatography-tandem mass spectrometry in the fern Psilotum nudum. The present study shows, for the first time, the presence of the auxin IAA, the cytokinins tZR, DHZR and iP, and the gibberellins GA(4), GA(9) and GA(20) in the rhizome and aerial shoots of this species and suggests a possible role of gibberellins in the evolution of ferns.

  10. Micropropagation of an elite F1 watermelon (Citrullus lanatus hybrid from the shoot tip of field grown plants

    Directory of Open Access Journals (Sweden)

    Mohammad Khalekuzzaman

    2012-06-01

    Full Text Available The aim of this work was to develop a protocol for rapid micropropagation of an elite F1 hybrid watermelon cultivar using shoot tip of field-grown plants. Maximum frequency (73% of shoot tip showed growth response in MS medium supplemented with 5 mg l-1 benzyl adenine (BA and 0.1 mg l-1 indole-3 acetic acid (IAA. Upon transfer to cytokinin-enriched medium, the cultures produced multiple shoots and 2.0 mg l-1 BA was optimum in this respect. Addition of gibberellic acid (GA3 in the multiplication medium resulted in better growth of shoots. Rooting rate was 100% when shoots were obtained from second subculture were cultured in medium with 1.0 mg l-1 indole-3 butyric acid (IBA. The shoots produced more roots with increasing number of subcultures. About 72% of the regenerated plantlets acclimatized successfully and survived in the soil condition.

  11. α-Glucosidase Inhibitory Constituents from Acanthopanax senticosus Harm Leaves

    Directory of Open Access Journals (Sweden)

    Hai-Xue Kuang

    2012-05-01

    Full Text Available A new triterpene glycoside, 3-O-[(α-L-rhamnopyranosyl(1→2]-[β-D-glucuronopyranosyl-6-O-methyl ester]-olean-12-ene-28-olic acid (1 and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5 were isolated from the leaves of Acanthopanax senticosus Harms along with six known compounds. The structures of the new compounds were determined by means of 2D-NMR experiments and chemical methods. All the isolated compounds were evaluated for their glycosidase inhibition activities and compound 6 showed significant α-glucosidase inhibition activity.

  12. Acetobacter intermedius, sp. nov.

    Science.gov (United States)

    Boesch, C; Trcek, J; Sievers, M; Teuber, M

    1998-03-01

    Strains of a new species in the genus Acetobacter, for which we propose the name A. intermedius sp. nov., were isolated and characterized in pure culture from different sources (Kombucha beverage, cider vinegar, spirit vinegar) and different countries (Switzerland, Slovenia). The isolated strains grow in media with 3% acetic acid and 3% ethanol as does A. europaeus, do, however, not require acetic acid for growth. These characteristics phenotypically position A. intermedius between A. europaeus and A. xylinus, DNA-DNA hybridizations of A. intermedius-DNA with DNA of the type strains of Acetobacter europaeus, A. xylinus, A. aceti, A. hansenii, A. liquefaciens, A. methanolicus, A. pasteurianus, A. diazotrophicus, Gluconobacter oxydans and Escherichia coli HB 101 indicated less than 60% DNA similarity. The important features of the new species are described. Acetobacter intermedius strain TF2 (DSM11804) isolated from the liquid phase of a tea fungus beverage (Kombucha) is the type strain.

  13. Physicochemical inactivation of Lassa, Ebola, and Marburg viruses and effect on clinical laboratory analyses

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, S.W.; McCormick, J.B.

    1984-09-01

    Clinical specimens from patients infected with Lassa, Ebola, or Marburg virus may present a serious biohazard to laboratory workers. The authors have examined the effects of heat, alteration of pH, and gamma radiation on these viruses in human blood and on the electrolytes, enzymes, and coagulation factors measured in laboratory tests that are important in the care of an infected patient. Heating serum at 60 degrees C for 1 h reduced high titers of these viruses to noninfectious levels without altering the serum levels of glucose, blood urea nitrogen, and electrolytes. Dilution of blood in 3% acetic acid, diluent for a leukocyte count, inactivated all of these viruses. All of the methods tested for viral inactivation markedly altered certain serum proteins, making these methods unsuitable for samples that are to be tested for certain enzyme levels and coagulation factors.

  14. Enzymic synthesis of indole-3-acetyl-1-O-beta-d-glucose. I. Partial purification and characterization of the enzyme from Zea mays

    Science.gov (United States)

    Leznicki, A. J.; Bandurski, R. S.

    1988-01-01

    The first enzyme-catalyzed reaction leading from indole-3-acetic acid (IAA) to the myo-inositol esters of IAA is the synthesis of indole-3-acetyl-1-O-beta-D-glucose from uridine-5'-diphosphoglucose (UDPG) and IAA. The reaction is catalyzed by the enzyme, UDPG-indol-3-ylacetyl glucosyl transferase (IAA-glucose-synthase). This work reports methods for the assay of the enzyme and for the extraction and partial purification of the enzyme from kernels of Zea mays sweet corn. The enzyme has an apparent molecular weight of 46,500 an isoelectric point of 5.5, and its pH optimum lies between 7.3 and 7.6. The enzyme is stable to storage at zero degrees but loses activity during column chromatographic procedures which can be restored only fractionally by addition of column eluates. The data suggest either multiple unknown cofactors or conformational changes leading to activity loss.

  15. NMR Spectroscopy Identifies Metabolites Translocated from Powdery Mildew Resistant Rootstocks to Susceptible Watermelon Scions.

    Science.gov (United States)

    Mahmud, Iqbal; Kousik, Chandrasekar; Hassell, Richard; Chowdhury, Kamal; Boroujerdi, Arezue F

    2015-09-16

    Powdery mildew (PM) disease causes significant loss in watermelon. Due to the unavailability of a commercial watermelon variety that is resistant to PM, grafting susceptible cultivars on wild resistant rootstocks is being explored as a short-term management strategy to combat this disease. Nuclear magnetic resonance-based metabolic profiles of susceptible and resistant rootstocks of watermelon and their corresponding susceptible scions (Mickey Lee) were compared to screen for potential metabolites related to PM resistance using multivariate principal component analysis. Significant score plot differences between the susceptible and resistant groups were revealed through Mahalanobis distance analysis. Significantly different spectral buckets and their corresponding metabolites (including choline, fumarate, 5-hydroxyindole-3-acetate, and melatonin) have been identified quantitatively using multivariate loading plots and verified by volcano plot analyses. The data suggest that these metabolites were translocated from the powdery mildew resistant rootstocks to their corresponding powdery mildew susceptible scions and can be related to PM disease resistance.

  16. Analgesic, anti-inflammatory and anti-pyretic activities of Thymus linearis.

    Science.gov (United States)

    Qadir, Muhammad Imran; Parveen, Amna; Abbas, Khizar; Ali, Muhammad

    2016-03-01

    The present study was aimed to investigate the antipyretic, analgesic and anti-inflammatory activity of aqueous methanolic and n-hexane extract of Thymus linearis. For measuring analgesic activity, writhing test, hot plate method and formalin test were performed and abdominal writhing was induced by intra-peritoneal injection of 0.2 ml of 3% acetic acid. While in formalin test, pain was experimentally induced by injecting 25 μl of 2.5% formalin in left hind paw. In hot plate method, pain was induced thermally by keeping the animals on a hot plate with temperature of about 51°C. Anti-inflammatory activity was assessed by carrageenan induced mice paw edema. For determination of antipyretic activity, pyrexia was induced by subcutaneous injection of 15% yeast. The results showed that both the extracts had significant analgesic activity (pThymus linearis may be used against pain, pyrexia and inflammation.

  17. Selective enrichment of Eicosapentaenoic acid (20:5n-3) in N. oceanica CASA CC201 by natural auxin supplementation.

    Science.gov (United States)

    Udayan, Aswathy; Arumugam, Muthu

    2017-10-01

    The present study aims to evaluate the effect of different concentration of natural auxin, Indole-3 acetic acid (IAA) on growth, lipid yield, PUFA and EPA accumulation in Nannochloropsis oceanica CASA CC201. It was observed that the, treatment with 10ppm concentration of IAA resulted in high cell number 579.5×10(6)cells/ml than the control (215.5×10(6)cells/ml). Treatment with IAA at a concentration of 40ppm gives the highest cellular lipid accumulation of 60.9% DCW than the control 31.05% DCW). Lipid yield is also found to be increased by the addition of 40ppm IAA (319.5mg/L) compared with the control (121.5mg/L). EPA percentage is increased to 10.76% by the addition of 40ppm IAA compared to the control (1.87%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Genome-wide analysis of Aux/IAA and ARF gene families in Populus trichocarpa

    Energy Technology Data Exchange (ETDEWEB)

    Kalluri, Udaya C [ORNL; DiFazio, Stephen P [West Virginia University; Brunner, A. [Virginia Polytechnic Institute and State University (Virginia Tech); Tuskan, Gerald A [ORNL

    2007-01-01

    Auxin/Indole-3-Acetic Acid (Aux/IAA) and Auxin Response Factor (ARF) transcription factors are key regulators of auxin responses in plants. A total of 35 Aux/IAA and 39 ARF genes were identified in the Populus genome. Comparative phylogenetic analysis revealed that the subgroups PoptrARF2, 6, 9 and 16 and PoptrIAA3, 16, 27 and 29 have differentially expanded in Populus relative to Arabidopsis. Activator ARFs were found to be two fold-overrepresented in the Populus genome. PoptrIAA and PoptrARF gene families appear to have expanded due to high segmental and low tandem duplication events. Furthermore, expression studies showed that genes in the expanded PoptrIAA3 subgroup display differential expression. The gene-family analysis reported here will be useful in conducting future functional genomics studies to understand how the molecular roles of these large gene families translate into a diversity of biologically meaningful auxin effects.

  19. Biosynthetic pathway of the phytohormone auxin in insects and screening of its inhibitors.

    Science.gov (United States)

    Suzuki, Hiroyoshi; Yokokura, Junpei; Ito, Tsukasa; Arai, Ryoma; Yokoyama, Chiaki; Toshima, Hiroaki; Nagata, Shinji; Asami, Tadao; Suzuki, Yoshihito

    2014-10-01

    Insect galls are abnormal plant tissues induced by galling insects. The galls are used for food and habitation, and the phytohormone auxin, produced by the insects, may be involved in their formation. We found that the silkworm, a non-galling insect, also produces an active form of auxin, indole-3-acetic acid (IAA), by de novo synthesis from tryptophan (Trp). A detailed metabolic analysis of IAA using IAA synthetic enzymes from silkworms indicated an IAA biosynthetic pathway composed of a three-step conversion: Trp → indole-3-acetaldoxime → indole-3-acetaldehyde (IAAld) → IAA, of which the first step is limiting IAA production. This pathway was shown to also operate in gall-inducing sawfly. Screening of a chemical library identified two compounds that showed strong inhibitory activities on the conversion step IAAld → IAA. The inhibitors can be efficiently used to demonstrate the importance of insect-synthesized auxin in gall formation in the future.

  20. Transport and Metabolism of the Endogenous Auxin Precursor lndole-3-Butyric Acid

    Institute of Scientific and Technical Information of China (English)

    Lucia C. Strader; Bonnie Bartel

    2011-01-01

    T Plant growth and morphogenesis depend on the levels and distribution of the plant hormone auxin. Plants tightly regulate cellular levels of the active auxin indole-3-acetic acid (IAA) through synthesis, inactivation, and transport. Although the transporters that move IAA into and out of cells are well characterized and play important roles in development, little is known about the transport of IAA precursors. In this review, we discuss the accumulating evidence suggesting that the IAA precursor indole-3-butyric acid (IBA) is transported independently of the characterized IAA transport machinery along with the recent identification of specific IBA efflux carriers and enzymes suggested to metabolize IBA. These studies have revealed important roles for IBA in maintaining IAA levels and distribution within the plant to support normal development.

  1. Physiological response of Tamarix ramosissima under water stress along the lower reaches of Tarim River

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Li; CHEN Yaning

    2006-01-01

    Tamarix ramosissima is one of the constructive species growing on both sides of Tarim River which is favorable to constituting a natural barrier containing local deserts and protecting the oasis. By analyzing characteristics of the main physiological indexes, such as chlorophyll, soluble sugar, proline (Pro), malondialdehyde (MDA), superoxide dismutase (SOD), peroxidase (POD), indole-3-acetic acid (IAA), C3-gibberellins (GA3) and abscisic acid (ABA), at different sections with different water tables in the lower reaches of Tarim River, it has been found that these physiological indexes have close correlations with water tables. In addition, the rational ecological, coercing and critical water tables of T. Ramosissima are 2-4 m, 6 m and 10 m, respectively, which provides an important theoretical basis for the ecological conservation of extremely arid regions.

  2. Simulation study of element plastic migration from radiometric measurements

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Faena M.L.; Manzoli, Jose Eduardo; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Soares, Eufemia Paez [Escola SENAI Fundacao Zerrenner, Sao Paulo, SP (Brazil)], E-mail: eufemia@sp.senai.br

    2007-07-01

    Element migration from plastic packaging to either foodstuffs or medicine is a serious public health. Many conventional experimental techniques such as chromatography-mass spectrometry, atomic absorption spectroscopy, inductively coupled plasma spectroscopy or calorimetric methods are used to measure total and specific migration of components from plastic packaging. The radiometric method is also used to measure the element migration. In this study a numerical technique was employed to simulate the experimental migration results obtained from measurements of elements from dairy product polymeric packages into 3% acetic acid solution which is a normative food simulant. This numerical technique can be used as complementary tool for the experimental measurements, allowing for a better understanding of the diffusion process and to estimate element migration situations not experimentally measured. (author)

  3. Production of 2-hydroxy-4-methoxybenzaldehyde in roots of tissue culture raised and acclimatized plants of Decalepis hamiltonii Wight & Arn., an endangered shrub endemic to Southern India and evaluation of its performance vis-a-vis plants from natural habitat.

    Science.gov (United States)

    Giridhar, P; Rajasekaran, T; Nagarajan, S; Ravishankar, G A

    2004-01-01

    Axillary buds obtained from field grown plants of D. hamiltonii were used to initiate multiple shoots on Murashige and Skoog's medium (MS) supplemented with 2 mg L(-1) 6-benzyl aminopurine (BA) and 0.5 mg L(-1) indole-3-acetic acid (IAA). Profuse rooting was achieved when the actively growing shoots were cultured on MS medium supplemented with 1.0 mg l(-1) indole-3-butyric acid (IBA). Regenerated plants were grown successfully in the plains, in contrast to wild growth in high altitudes and rocky crevices of hilly regions. Roots of different sizes from one-year-old tissue culture raised field grown plants had the same profile of 2-hydroxy-4-methoxybenzaldehyde as that of wild plants. A maximum of 0.14% and 0.12% 2-hydroxy-4-methoxybenzaldehyde was produced in roots of one year old tissue culture derived plants and greenhouse grown plants respectively.

  4. Study on Migration of Melamine from Food Packaging Materials on Markets

    Institute of Scientific and Technical Information of China (English)

    JIE LU; JING XIAO; DA-JIN YANG; ZHU-TIAN WANG; DING-GUO JIANG; CONG-RONG FANG; JIE YANG

    2009-01-01

    Objectives To study the migration of melamine into foods from plastic food packaging materials and dairy product containers commonly used in China. Methods 37 samples were collected from the market. The EU migration testing conditions were adopted with distilled water, 3% acetic acid, n-hexane and 15% ethanol being chosen as the simulating solutions. The HPLC method was used to detect melamine. Results No melamine was detected in 15 dairy product containers. Among the 22 plastic samples, 16 of polypropylene, and polycarbonate types had no delectable amount melamine while a low level of melamine was found in 3 of the 6 melamine resin containers. Conclusion Migration of melamine from food packaging materials in China market is in line with the requirements of EU.

  5. Azetidinic amino acids

    DEFF Research Database (Denmark)

    Bräuner-Osborne, Hans; Bunch, Lennart; Chopin, Nathalie

    2005-01-01

    A set of ten azetidinic amino acids, that can be envisioned as C-4 alkyl substituted analogues of trans-2-carboxyazetidine-3-acetic acid (t-CAA) and/or conformationally constrained analogues of (R)- or (S)-glutamic acid (Glu) have been synthesized in a diastereo- and enantiomerically pure form from...... of two diastereoisomers that were easily separated and converted in two steps into azetidinic amino acids. Azetidines 35-44 were characterized in binding studies on native ionotropic Glu receptors and in functional assays at cloned metabotropic receptors mGluR1, 2 and 4, representing group I, II and III...... beta-amino alcohols through a straightforward five step sequence. The key step of this synthesis is an original anionic 4-exo-tet ring closure that forms the azetidine ring upon an intramolecular Michael addition. This reaction was proven to be reversible and to lead to a thermodynamic distribution...

  6. Nanofabrication of organic/inorganic hybrids of TiO2 with substituted phthalocyanine or polythiophene.

    Science.gov (United States)

    Ding, H; Ram, M K; Nicolini, C

    2001-06-01

    Organic photovoltaic cells, similar to Grätzel type, have been widely investigated in recent years. In the case of Grätzel-type cells, TiO2 colloids are usually spin-coated onto an electrode and then sintered. Later, such electrodes are immersed in dye solution to sensitize the TiO2 layer for fabrication of photovoltaic cells. In the current study, an attempt was made to fabricate photovoltaic cells using a layer-by-layer technique. Based on such a method, ordered substituted phthalocyanine or conducting polythiophene-sensitized TiO2 multilayers were fabricated at the molecular level. Buildup of multilayer films of copper phthalocyanine-capped TiO2 and poly(thiophene-3-acetic acid)/TiO2 was monitored by increments in the UV-visible absorption and the frequency decrease of quartz crystal microbalance. The ordered multilayers were further characterized by infrared spectroscopy, and electrochemical and photoelectrochemical measurements.

  7. Three new triterpene esters from pumpkin (Cucurbita maxima) seeds.

    Science.gov (United States)

    Kikuchi, Takashi; Ueda, Shinsuke; Kanazawa, Jokaku; Naoe, Hiroki; Yamada, Takeshi; Tanaka, Reiko

    2014-04-16

    Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1), 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2), and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3), were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11)-diene-3α,29-diol 3,29-dibenzoate (4). Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5-93.7 μM against HL-60 and P388 cells.

  8. Micropropagation of Cordyline terminalis.

    Science.gov (United States)

    Ray, Tui; Saha, Prasenjit; Roy, Satyesh C

    2013-01-01

    This protocol describes an efficient and rapid method for large-scale multiplication of Cordyline terminalis in a cost-effective manner. Actively growing shoot tips were selected as explants. Murashige and Skoog (MS) basal medium was supplemented with different plant growth regulators at various developmental stages of C. terminalis. The highest percentage of regeneration (95 ± 2.8) and average number of shoot buds (60.2 ± 4.4) per explant were obtained in medium containing 80 mg /L adenine sulfate (AdSO(4)), 2 mg/L 6-benzyladenine (BA), and 0.1 mg/L indole-3-acetic acid (IAA). Thousands of micropropagated plants were produced within 4-5 months using this protocol.

  9. Highly sensitive assay for the measurement of serotonin in microdialysates using capillary high-performance liquid chromatography with electrochemical detection.

    Science.gov (United States)

    Parrot, Sandrine; Lambás-Señas, Laura; Sentenac, Sabine; Denoroy, Luc; Renaud, Bernard

    2007-05-01

    A highly sensitive isocratic capillary high-performance liquid chromatographic (HPLC) method with electrochemical detection (ED) for the simultaneous measurement of serotonin (5-hydroxytryptamine, 5-HT) and its metabolite 5-hydroxyindole-3-acetic acid (5-HIAA) in microdialysates has been developed using a 0.5 mm i.d. capillary column and a 11-nL detection cell. This method, validated on both pharmacological and analytical bases, can be performed using injection volumes as low as 1 microL. The limits of detection were 5.6 x 10(-11)mol/L and 3.0 x 10(-9)mol/L for 5-HT and 5-HIAA. Several applications of the present method are given on microdialysates from rodent brain and human spinal cord.

  10. Effects of 2,4-D and 4-CPA on yield and quality of the tomato, Lycopersicon esculentum Miller (Solanaceae)

    DEFF Research Database (Denmark)

    Gemici, Meliha; Türkyilmaz, B.; Tan, Kit

    2007-01-01

    economy. Our tests confirm that application of concentrations in excess of the recommended dosage produces deformed and inferior fruit, increases fruit number and incidence of parthenocarpy. The use of growth regulators led to an increase in the levels of the internal plant hormone indol-3 acetic acid......Synthetic plant growth substances augment plant growth when applied at specific concentrations; they are also reported as without causing significant increases in the amount of internal plant hormones. Exceeding recommended dosages, however, affects yield and quality adversely. An experiment......, to test the effects of high concentrations of two growth regulators 2,4- dichlorophenoxy acetic acid (2,4-D) and 4-chlorophenoxy acetic acid (4-CPA) on fruit development in the tomato plant, was carried out. This plant is grown on a large scale in Turkey, contributing to and supporting the national...

  11. Difference in in vitro response and esculin content in two populations of Taraxacum officinale Weber.

    Science.gov (United States)

    Jamshieed, Sumiya; Das, Sandip; Sharma, M P; Srivastava, P S

    2010-12-01

    In vitro micropropagation has been achieved in medicinally important plant, Taraxacum officinale collected from two different regions, Kashmir (J & K) and Garhwal (Uttarakhand). Leaf segments inoculated on MS supplemented with different combinations of Indole-3-acetic acid (IAA) and Benzyladenine (BA) produced indirect regeneration. For root induction MS fortified with Indole-3-butyric acid (IBA) was used. Taraxacum officinale collected from Garhwal responded two weeks earlier and showed shoot regeneration whereas in Kashmir population only callus proliferation occurred. Esculin content was also higher in the samples from Garhwal. The content was affected by both, the hormone concentration as well as age of the cultures. RAPD of the in vitro raised regenerants confirmed genetic stability.

  12. Molecular interactions between caffeine and catechins in green tea.

    Science.gov (United States)

    Colon, Marta; Nerin, Cristina

    2014-07-16

    Migration of green tea components from an active packaging material containing green tea extract was performed in water and 3% acetic acid in water. The migration values for acid simulant were much higher than the values obtained in water. The influence of the acidic media in solutions of catechin standards and green tea extract was evaluated by liquid chromatography. Catechin, epicatechin, and caffeine from the green tea extract exhibited major variation in their concentrations values, with increases of 29.90, 20.75, and 15.95%, respectively, in acidic medium. The results suggested that catechins and caffeine form complexes through intermolecular interactions in neutral media and that these interactions are broken in acidic media. The continuous variation method was also performed to confirm the stoichiometry of the complexes between catechins and caffeine. Finally, a computer simulation was applied by Chem Pro 12.0, and the energies involved were calculated to confirm the experimental results obtained.

  13. Determination of tryptophan and tryptophan metabolites in grape must and wine.

    Science.gov (United States)

    Hoenicke, K; Simat, T J; Steinhart, H; Christoph, N; Köhler, H J; Schwab, A

    1999-01-01

    Tryptophan (Trp) and its metabolites, especially indole-3-acetic acid (IAA), are considered as potential precursors of 2-aminoacetophenone (AAP), an aroma compound which causes the "untypical aging off-flavor" (UTA) in Vitis vinifera white wines. In this study RP-HPLC with fluorescence detection was used for the qualitative and quantitative analysis of Trp and Trp-metabolites in 39 grapes, 22 grape musts and 16 wines, to which different viticultural conditions (ripeness, pruning, strip of leaves, soil condition) have been applied. A sensitive and selective determination was achieved after solid phase extraction using an anion exchange material. Only traces of Trp-metabolites could be determined in the examined grapes and grape musts, but their amounts increased significantly during fermentation, whereas the amount of Trp decreased. Different viticultural measures, besides the time of grape harvest, showed no significant influences on the amount of Trp and Trp-metabolites.

  14. Auxin level and regeneration of Begonia leaves.

    Science.gov (United States)

    Heide, O M

    1968-06-01

    As previously found, both the level of ether-extractable auxin (presumably indole-3-acetic acid) and the root-forming ability of B.xcheimantha leaves are increased under long-day conditions by high temperature, whereas the capacity for adventitious bud formation is reduced. However, this relation is present under relatively high light intensity only. Under the low light intensities in late fall neither auxin level nor regeneration ability were significantly affected by temperature.Dark treatment of detached leaves for 2 to 16 days greatly counteracted the inhibitory effect of high temperature on bud formation and reduced both the auxin level and the root-forming ability of the leaves.The great seasonal changes in the regeneration ability of Begonia leaves seem to be the result of a complex interaction of temperature, day-length, and daily light energy on the level of endogenous auxin and other growth regulators.

  15. Possible effects of organelle charge and density on cell metabolism. [chemical response to gravitational stimulus

    Science.gov (United States)

    Bandurski, Robert S.; Schulze, Aga; Domagalski, W.

    1986-01-01

    A system of perception and transduction involving the gravity-induced asymmetric distribution of a plant growth hormone is studied. A theory is constructed which assumes that the perception of the gravitational stimulus involved a perturbation of the plant's bioelectric field and that the transduction of the stimulus involved voltage-gating of hormone movement from the plant's vascular tissue into the hormone responsive growing tissue. Particular attention is focused on the barriers to indole-3-acetic acid (IAA) transport from the seed to the mesocotyl cortex, the protoinhibition of IAA movement from the endosperm to the shoot, the effects of the gravitational stimulus on the movement of IAA from the kernel to the shoot, electrochemical gating as a target for the gravity stimulus, and the gravity sensing mechanism.

  16. Enzymic synthesis of indole-3-acetyl-1-O-beta-d-glucose. I. Partial purification and characterization of the enzyme from Zea mays

    Science.gov (United States)

    Leznicki, A. J.; Bandurski, R. S.

    1988-01-01

    The first enzyme-catalyzed reaction leading from indole-3-acetic acid (IAA) to the myo-inositol esters of IAA is the synthesis of indole-3-acetyl-1-O-beta-D-glucose from uridine-5'-diphosphoglucose (UDPG) and IAA. The reaction is catalyzed by the enzyme, UDPG-indol-3-ylacetyl glucosyl transferase (IAA-glucose-synthase). This work reports methods for the assay of the enzyme and for the extraction and partial purification of the enzyme from kernels of Zea mays sweet corn. The enzyme has an apparent molecular weight of 46,500 an isoelectric point of 5.5, and its pH optimum lies between 7.3 and 7.6. The enzyme is stable to storage at zero degrees but loses activity during column chromatographic procedures which can be restored only fractionally by addition of column eluates. The data suggest either multiple unknown cofactors or conformational changes leading to activity loss.

  17. Spatiotemporal manipulation of auxin biosynthesis in cotton ovule epidermal cells enhances fiber yield and quality.

    Science.gov (United States)

    Zhang, Mi; Zheng, Xuelian; Song, Shuiqing; Zeng, Qiwei; Hou, Lei; Li, Demou; Zhao, Juan; Wei, Yuan; Li, Xianbi; Luo, Ming; Xiao, Yuehua; Luo, Xiaoying; Zhang, Jinfa; Xiang, Chengbin; Pei, Yan

    2011-05-01

    The capacity of conventional breeding to simultaneously improve the yield and quality of cotton fiber is limited. The accumulation of the plant hormone indole-3-acetic acid (IAA) in cotton fiber initials prompted us to investigate the effects of genetically engineering increased IAA levels in the ovule epidermis. Targeted expression of the IAA biosynthetic gene iaaM, driven by the promoter of the petunia MADS box gene Floral Binding protein 7 (FBP7), increased IAA levels in the epidermis of cotton ovules at the fiber initiation stage. This substantially increased the number of lint fibers, an effect that was confirmed in a 4-year field trial. The lint percentage of the transgenic cotton, an important component of fiber yield, was consistently higher in our transgenic plants than in nontransgenic controls, resulting in a >15% increase in lint yield. Fiber fineness was also notably improved.

  18. OPTIMISATION OF A HYDROPHILIC INTERACTION LIQUID CHROMATOGRAPHY METHOD FOR CATECHOLAMINES AND RELATED MOLECULES ANALYSIS

    Directory of Open Access Journals (Sweden)

    RALUCA-IOANA CHIRITA-TAMPU

    2017-03-01

    Full Text Available A simple and specific method for the analysis of 11 compounds (catecholamines, their precursors and their metabolites has been developed using hydrophilic interaction chromatography. Adrenaline, noradrenalin, dopamine, serotonin, 3,4-dihydroxy-phenylalanine, 3-methoxytyramine, tryptophan, homovanillic acid, tyrosine, 3,4-dihydroxy-phenylacetic acid, 5-hydroxyindole-3-acetic acid and 3,4-dihydroxybenzylalanine (as internal standard were separated on a TSK gel amide 80 column. The influence of parameters such as organic modifier type and content, salt nature and concentration, pH as well as column temperature on the selectivity were investigated. The optimized mobile phase consisted of a 20 mM ammonium acetate aqueous solution buffered at pH 3 and acetonitrile (20:80 v/v mixture.

  19. Phytohormone Production by Strains of Pantoea agglomerans from Knots on Olive Plants Caused by Pseudomonas savastanoi pv. savastanoi

    Directory of Open Access Journals (Sweden)

    A. Cimmino

    2006-12-01

    Full Text Available Pantoea agglomerans is a common epiphyte of many plant species, and it is associated with Pseudomonas savastanoi pv. savastanoi in young and apparently intact olive knots. Strains of P. agglomerans collected from various olive groves in central Italy were studied for their ability to accumulate plant growth substances in culture. All the strains produced indole-3-aldehyde, indole-3-ethanol and indole-3-acetic acid (IAA, this last compound in amounts (average 8.7 mg l-1 comparable to those produced in vitro by virulent strains of P. savastanoi. None of the olive strains produced cytokinins. It is suggested that the IAA produced by P. agglomerans may increase the size of the knots caused on olive by P. savastanoi.

  20. Preparation and characterization of a sulindac sensor based on PVC/TOA-SUL membrane.

    Science.gov (United States)

    Lenik, Joanna

    2014-04-01

    A potentiometric sulindac sensitive sensor based on tetraoctylammonium (Z)-5-fluoro-2-methyl-1-[[p-(methylsulfinyl)phenyl]methylene]-1H-indene-3-acetate (TOA-SUL) was described. The electrode responded with sensitivity of 57.5±1.6mV decade(-1) over the linear range 5×10(-5)-1×10(-2)mol L(-1) at pH6.0-9.0. It had the limit of detection 1.4×10(-5)mol L(-1), a fast response time of 13s and showed clear discrimination of sulindac ions from several inorganic and organic compounds and also amino acids. This electrode did not contain any inner solutions, so it was easy and comfortable to use. The proposed sensor was used to determine sulindac in clear solution and in urine sample solution.

  1. Auxin effectively induces the formation of the secondary abscission zone in Bryophyllum calycinum Salisb. (Crassulaceae

    Directory of Open Access Journals (Sweden)

    Marian Saniewski

    2016-05-01

    Full Text Available We have found that auxin, indole-3-acetic acid (IAA substantially induces the formation of the secondary abscission zone in stem and petiole explants and in decapitated stem and petiole after excision of blade in intact plants of Bryophyllum calycinum when IAA at a concentration of 0.1% as lanolin paste was applied in the middle of these organs. The secondary abscission zone was formed at a few mm above of the treatment with IAA, and senescence of the part above abscission zone was observed. IAA additionally applied on the top of explants or top of the dacapitated stem or the debladed petiole totally prevented the secondary abscission zone formation and senescence induced by IAA applied in the middle of these organs. Possible mechanisms of the formation of the secondary abscission zone are discussed in terms of the interaction of auxin and ethylene.

  2. Migration of 2-butoxyethyl acetate from polycarbonate infant feeding bottles

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Lund, K.H.

    2003-01-01

    An enforcement campaign was carried out to assess the migration of 2-butoxyethyl acetate (2-BEA) from polycarbonate infant feeding bottles intended for repeated use. Migration was measured by three successive migration tests into two of the European Union official food simulants: distilled water...... and 3% acetic acid testing at 40degrees C for 10 days. The Danish Veterinary and Food Administration (DVFA) has assessed that a migration above 0.33 mg for 2-BEA and a group of eight related substances kg(-1) foodstuff from plastics articles used exclusively for infants is unacceptable. Migration of 2......-BEA was found from eight of 12 bottles. However, migration above the target value of 0.33 mg kg(-1) was not observed in the third decisive test from any of the 12 different brands of polycarbonate feeding bottles. A migration of between 0.05 and 0.26 mg kg(-1) from seven of 12 bottles was measured...

  3. Competitive inhibition of transcription factors by small interfering peptides.

    Science.gov (United States)

    Seo, Pil Joon; Hong, Shin-Young; Kim, Sang-Gyu; Park, Chung-Mo

    2011-10-01

    Combinatorial assortment by dynamic dimer formation diversifies gene transcriptional specificities of transcription factors. A similar but biochemically distinct mechanism is competitive inhibition in which small proteins act as negative regulators by competitively forming nonfunctional heterodimers with specific transcription factors. The most extensively studied is the negative regulation of auxin response factors by AUXIN/INDOLE-3-ACETIC ACID repressors. Similarly, Arabidopsis thaliana (Arabidopsis) little zipper and mini finger proteins act as competitive inhibitors of target transcription factors. Competitive inhibitors are also generated by alternative splicing and controlled proteolytic processing. Because they provide a way of attenuating transcription factors we propose to call them small interfering peptides (siPEPs). The siPEP-mediated strategy could be applied to deactivate specific transcription factors in crop plants.

  4. Effect of PGR producing bacterial strains isolated from vermisources on germination and growth of Vigna unguiculata (L. Walp.

    Directory of Open Access Journals (Sweden)

    Anandharaj Marimuthu

    2014-12-01

    Full Text Available Nineteen bacterial strains were isolated from vermisources andscreened for Indole-3-acetic acid (IAA production among themonly nine strains produce IAA and they were identified asStreptococcus spp., Micrococcus spp., Klebsiella spp., Bacillus spp., Enterobacter spp., Escherichia spp., Alcaligenes spp., Erwinia spp., and Pseudomonas spp. Among all other strains Bacillus sp. showed the higher IAA production hence selected for further molecular analysis and confirmed as Bacillus cereus. The B. cereus was grown in nutrient broth supplemented with different concentrations (1, 2, 3, 4 and 5mg/ml of tryptophan for seven days at pH 7 and at 37ºC. Crude IAA was used for in vitro phytostimulatory studies using Vigna unguiculata (L. Walp. The plant growth parameters were analyzed at different day intervals (5, 10 and 15 days. Supplementation of 5 ml crude IAA (2mg/ml of tryptophan dynamically enhances the plant growth parameters after 15 days.

  5. Influence of lead on auxin-induced cell elongation

    Directory of Open Access Journals (Sweden)

    Marek Burzyński

    2014-01-01

    Full Text Available The influence of lead chloride on plant tissue growth is described. Lead reduced elongation of etiolated wheat coleoptile segments, green pea epicotyl fragments and etiolated and green sunflower hypocotyls. Green tissues were more susceptible to lead than etiolated ones. PbCl2 in a 10-4 M concentration significantly reduced plastic and elastic extensibility of the wheat coleoptile cell walls and diminished the hydration of sunflower hypocotyl segments. Auxin (indolyl-3-acetic acid - IAA applied in concentration optimal for growth of the particular tissues partly attenuated the inhibitory action of lead on elongation, plastic and elastic extensibility and water absorption. Auxin applied in supraoptimal concentrations did not abolish the inhibitory action of lead on tissue growth.

  6. Phytotoxical effect of Lepidium draba L. extracts on the germination and growth of monocot (Zea mays L.) and dicot (Amaranthus retroflexus L.) seeds.

    Science.gov (United States)

    Kaya, Yusuf; Aksakal, Ozkan; Sunar, Serap; Erturk, Filiz Aygun; Bozari, Sedat; Agar, Guleray; Erez, Mehmet Emre; Battal, Peyami

    2015-03-01

    Laboratory experiments were performed to determine phytotoxic potentials of white top (Lepidium draba) methanol extracts (root, stem and leaf) on germination and early growth of corn (Zea mays) and redroot pigweed (Amaranthus retroflexus). Furthermore, the effects of different methanol extracts of L. draba on the phytohormone (indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and zeatin) levels of corn and redroot pigweed were investigated. It was observed that all concentrations of methanol extracts of root, stem and leaf of L. draba inhibited germination, radicle and plumule elongation when compared with the respective controls. Besides this, the degree of inhibition was increased in concert with increasing concentrations of extracts used. On the other hand, phytohormone levels changed with the application of different extract concentrations. Comparing with the control, the GA levels significantly decreased while the ABA levels increased in all the application groups. Zeatin and IAA levels showed changes depending upon the applied extracts and concentrations.

  7. Androgenesis in Citrus aurantifolia (Christm.) swingle.

    Science.gov (United States)

    Chaturvedi, H C; Sharma, A K

    1985-07-01

    Embryoids were differentiated from anthers of C. aurantifolia which were first floated on a modified Murashige and Skoog's liquid medium supplemented with 0.5 mg/l N(6)-benzylaminopurine and 1 mg/l indole-3-acetic acid for 20-30 d, followed by 30 d culture in semisolid Schenk and Hildebrandt's medium having the same growth hormones. Embryoids originated from within the anther lobes. Initially, a few embryoids were formed by each anther; later, they multiplied rapidly by the production of new embryoids from the hypocotyl and cotyledon portions of the original embryoids. The embryoids could develop into plantlets, which were all diploid (2n=18). The androgenic plants grew normally in soil.

  8. Plant growth-promoting traits of yeasts isolated from the phyllosphere and rhizosphere of Drosera spatulata Lab.

    Science.gov (United States)

    Fu, Shih-Feng; Sun, Pei-Feng; Lu, Hsueh-Yu; Wei, Jyuan-Yu; Xiao, Hong-Su; Fang, Wei-Ta; Cheng, Bai-You; Chou, Jui-Yu

    2016-03-01

    Microorganisms can promote plant growth through direct and indirect mechanisms. Compared with the use of bacteria and mycorrhizal fungi, the use of yeasts as plant growth-promoting (PGP) agents has not been extensively investigated. In this study, yeast isolates from the phyllosphere and rhizosphere of the medicinally important plant Drosera spatulata Lab. were assessed for their PGP traits. All isolates were tested for indole-3-acetic acid-, ammonia-, and polyamine-producing abilities, calcium phosphate and zinc oxide solubilizing ability, and catalase activity. Furthermore, the activities of siderophore, 1-aminocyclopropane-1-carboxylate deaminase, and fungal cell wall-degrading enzymes were assessed. The antagonistic action of yeasts against pathogenic Glomerella cingulata was evaluated. The cocultivation of Nicotiana benthamiana with yeast isolates enhanced plant growth, indicating a potential yeast-plant interaction. Our study results highlight the potential use of yeasts as plant biofertilizers under controlled and field conditions. Copyright © 2016 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  9. Method for assessing lead, cadmium, mercury and arsenic in high-density polyethylene packaging and study of the migration into yoghurt and simulant.

    Science.gov (United States)

    Kiyataka, Paulo Henrique M; Dantas, Sílvia T; Pallone, Juliana Azevedo Lima

    2014-01-01

    The purpose of this paper was to assess the concentration of lead (Pb), cadmium (Cd), mercury (Hg) and arsenic (As) in high-density polyethylene (HDPE) packaging intended for contact with yoghurt and the migration of these elements using the food itself and 3% acetic acid as a food simulant in accordance to ANVISA, the Brazilian Health Surveillance Agency. In order to perform this study, it was necessary to develop and validate a method by inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis. For method validation, the parameters linearity, limits of detection (LODs) and quantification (LOQs), accuracy and precision were determined. Fifteen commercial samples of yoghurt, marketed in Campinas - São Paulo (Brazil), were used for the analysis. The packaging and yoghurt were digested in high-pressure ashing equipment (HPA) and the migration of the elements into simulant were determined directly in the solution. The validated method proved adequate and the results obtained showed that all the packaging had levels of Hg and Cd below the LOQ, corresponding to 1.0 and 1.5 μg l(-1), respectively. The highest levels of As and Pb were 0.87 and 462.3 mg kg(-1), respectively. The migration of these elements to the yoghurt after 45 days of contact at 4ºC was below the LOQ for all the samples assessed. The results of specific migration into 3% acetic acid simulant showed the concentrations of Cd, Hg and As below 5, 5 and 10 µg kg(-1), respectively, which are the maximum limits set by ANVISA. However, for three samples the packaging lid showed migration of Pb into simulant ranging from 30.6 to 40.2 μg kg(-1), exceeding the limit set by ANVISA of 10 μg kg(-1).

  10. High-frequency in vitro plantlet regeneration from apical bud as a novel explant of Carum copticum L.

    Institute of Scientific and Technical Information of China (English)

    Mansoureh Salehi; Bahman Hosseini; Zohreh Jabbarzadeh

    2014-01-01

    Objective: To develop an in vitro regeneration system to increase the recovery of Carum copticum L. plantlets as a part of developing a metabolic engineering program.Methods:3-acetic acid and indole butyric acid on direct shoot regeneration and rooting of ajowan from apical bud explants were assessed. All explants were cultured on Murashige and Skoog (MS) medium supplemented with different combinations of 6-benzyl amino purine (BAP) (0, 2.2, 4.4, 8.8µ The efficacy of different concentrations and combinations of 6-benzyladenine, indole-Results: The maximum shoot regeneration frequency (97.5%) and the highest number of shoots produced from apical buds (34 shoots per explant) were obtained on MS medium fortified with BAP (4.4 µmol/L) and IAA (0.5 µmol/L). Low shoot regeneration frequency was observed in BAP free treatments. The effects of different strengths of MS medium and various concentrations of IAA and indole-3- butyric acid on rooting rate, length and average number of roots were also investigated. Application of indole-3- butyric acid (6 µmol/L) in full-strength MS medium, was more effective than IAA and resulted in highest shoot regeneration frequency with the rooting rate of 100% and highest mean number of roots per shoot (41.8). The rooted plantlets were acclimatized successfully in greenhouse conditions with a survival rate of 90%. mol/L) and indole-3-acetic acid (IAA) (0, 0.5, 1.1, 2.2 µmol/L). Conclusion: In this study, a simple and reliable regeneration and acclimatization protocol for Carum copticum has been presented. This protocol can be found very advantageous for a variety of purposes, including mass multiplication of Carum species, medicinal plant breeding studies and transgenic plant production.

  11. 5 prime -Azido-(3,6- sup 3 H sub 2 )-1-naphthylphthalamic acid, a photoactivatable probe for naphthylphthalamic acid receptor proteins from higher plants: Identification of a 23-kDa protein from maize coleoptile plasma membranes

    Energy Technology Data Exchange (ETDEWEB)

    Zettl, R.; Feldwisch, J.; Schell, J.; Palme, K. (Max-Planck-Inst. fuer Zuechtungsforschung, Koeln (West Germany)); Boland, W. (Univ. Karlsruhe (West Germany))

    1992-01-15

    1-Naphthylphthalamic acid (NPA) is a specific inhibitor of polar auxin transport that blocks carrier mediated auxin efflux from plant cells. To allow identification of the NPA receptor thought to be part of the auxin efflux carrier, the authors have synthesized a tritiated, photolabile NPA analogue, 5{prime}-azido-(3,6-{sup 3}H{sub 2})NPA (({sup 3}H{sub 2})N{sub 3}NPA). This analogue was used to identify NPA-binding proteins in fractions highly enriched for plasma membrane vesicles isolated from maize coleoptiles (Zea mays L.). Competition studies showed that binding of ({sup 3}H{sub 2})N{sub 3}NPA to maize plasma membrane vesicles was blocked by nonradioactive NPA but not by benzoic acid. After incubation of plasma membrane vesicles with ({sup 3}H{sub 2})N{sub 3}NPA and exposure to UV light, they observed specific photoaffinity labeling of a protein with an apparent molecular mass of 23 kDa. Pretreatment of the plasma membrane vesicles with indole-3-acetic acid or with the auxin-transport inhibitors NPA and 2,3,5-triiodobenzoic acid strongly reduced specific labeling of this protein. This 23-kDa protein was also labeled by addition of 5-azido-(7-{sup 3}H)indole-3-acetic acid to plasma membranes prior to exposure to UV light. The 23-kDa protein was solubilized from plasma membranes by 1% Triton X-100. The possibility that this 23-kDa polypeptide is part of the auxin efflux carrier system is discussed.

  12. Auxin-induced fruit-set in tomato is mediated in part by gibberellins.

    Science.gov (United States)

    Serrani, Juan Carlos; Ruiz-Rivero, Omar; Fos, Mariano; García-Martínez, José Luis

    2008-12-01

    Tomato (Solanum lycopersicum L.) fruit-set and growth depend on gibberellins (GAs). Auxins, another kind of hormone, can also induce parthenocarpic fruit growth in tomato, although their possible interaction with GAs is unknown. We showed that fruit development induced by the auxins indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid (2,4-D) were significantly reduced by the simultaneous application of inhibitors of GA biosynthesis, and that this effect was reversed by the application of GA(3). This suggested that the effect of auxin was mediated by GA. Parthenocarpic fruits induced by 2,4-D had higher levels of the active GA(1), its precursors and metabolites, than unpollinated non-treated ovaries, but similar levels as those found in pollinated ovaries. Application experiments of radioactive-labelled GAs to unpollinated ovaries showed than 2,4-D altered GA metabolism (both biosynthesis and catabolism) in vivo. Transcript levels of genes encoding copalyldiphosphate synthase (SlCPS), SlGA20ox1, SlGA20ox2 and SlGA20ox3, and SlGA3ox1 were higher in unpollinated ovaries treated with 2,4-D. In contrast, transcript levels of SlGA2ox2 (out of the five SlGA2ox genes known to encode this kind of GA-inactivating enzyme) were lower in ovaries treated with 2,4-D. Our results support the idea that auxins induce fruit-set and growth in tomato, at least partially, by enhancing GA biosynthesis (GA 20-oxidase, GA 3-oxidase and CPS), and probably by decreasing GA inactivation (GA2ox2) activity, thereby leading to higher levels of GA(1). The expression of diverse Aux/indole-3-acetic acid (IAA) and auxin response factors, which may be involved in this effect of auxin, was also altered in 2,4-D-induced ovaries.

  13. Randomised, double-blind, placebo-controlled trial with azithromycin selects for anti-inflammatory microbial metabolites in the emphysematous lung

    Science.gov (United States)

    Segal, Leopoldo N; Clemente, Jose C; Wu, Benjamin G; Wikoff, William R; Gao, Zhan; Li, Yonghua; Ko, Jane P; Rom, William N; Blaser, Martin J; Weiden, Michael D

    2017-01-01

    Introduction Azithromycin (AZM) reduces pulmonary inflammation and exacerbations in patients with COPD having emphysema. The antimicrobial effects of AZM on the lower airway microbiome are not known and may contribute to its beneficial effects. Here we tested whether AZM treatment affects the lung microbiome and bacterial metabolites that might contribute to changes in levels of inflammatory cytokines in the airways. Methods 20 smokers (current or ex-smokers) with emphysema were randomised to receive AZM 250 mg or placebo daily for 8 weeks. Bronchoalveolar lavage (BAL) was performed at baseline and after treatment. Measurements performed in acellular BAL fluid included 16S rRNA gene sequences and quantity; 39 cytokines, chemokines and growth factors and 119 identified metabolites. The response to lipopolysaccharide (LPS) by alveolar macrophages after ex-vivo treatment with AZM or bacterial metabolites was assessed. Results Compared with placebo, AZM did not alter bacterial burden but reduced α-diversity, decreasing 11 low abundance taxa, none of which are classical pulmonary pathogens. Compared with placebo, AZM treatment led to reduced in-vivo levels of chemokine (C-X-C) ligand 1 (CXCL1), tumour necrosis factor (TNF)-α, interleukin (IL)-13 and IL-12p40 in BAL, but increased bacterial metabolites including glycolic acid, indol-3-acetate and linoleic acid. Glycolic acid and indol-3-acetate, but not AZM, blunted ex-vivo LPS-induced alveolar macrophage generation of CXCL1, TNF-α, IL-13 and IL-12p40. Conclusion AZM treatment altered both lung microbiota and metabolome, affecting anti-inflammatory bacterial metabolites that may contribute to its therapeutic effects. Trial registration number NCT02557958. PMID:27486204

  14. Plant Growth Promoting Bacteria Associated with Langsdorffia hypogaea-Rhizosphere-Host Biological Interface: A Neglected Model of Bacterial Prospection

    Science.gov (United States)

    Felestrino, Érica B.; Santiago, Iara F.; Freitas, Luana da Silva; Rosa, Luiz H.; Ribeiro, Sérvio P.; Moreira, Leandro M.

    2017-01-01

    Soil is a habitat where plant roots and microorganisms interact. In the region of the Brazilian Iron Quadrangle (IQ), studies involving the interaction between microbiota and plants have been neglected. Even more neglected are the studies involving the holoparasite plant Langsdorffia hypogaea Mart. (Balanophoraceae). The geomorphological peculiarities of IQ soil, rich in iron ore, as well as the model of interaction between L. hypogaea, its hosts and the soil provide a unique niche that acts as selective pressure to the evolution of plant growth-promoting bacteria (PGPB). The aim of this study was to prospect the bacterial microbiota of holoparasitic plant L. hypogaea, its plant host and corresponding rhizosphere of IQ soil, and to analyze the potential of these isolates as PGPB. We obtained samples of 11 individuals of L. hypogaea containing fragments of host and rhizosphere remnants, resulting in 81 isolates associated with Firmicutes and Proteobacteria phyla. The ability to produce siderophores, hydrocyanic acid (HCN), indole-3-acetic acid (IAA), nitrogen (N2) fixation, hydrolytic enzymes secretion and inhibition of enteropathogens, and phytopathogens were evaluated. Of the total isolates, 62, 86, and 93% produced, respectively, siderophores, IAA, and were able to fix N2. In addition, 27 and 20% of isolates inhibited the growth of enteropathogens and phytopathogens, respectively, and 58% were able to produce at least one hydrolytic activity investigated. The high number of isolates that produce siderophores and indole-3-acetic acid suggests that this microbiota may be important for adaptation of plants to IQ. The results demonstrate for the first time the biological importance of Brazilian IQ species as reservoirs of specific microbiotas that might be used as PGPB on agricultural land or antropized soils that needs to be reforested. PMID:28239369

  15. Revealing the biotechnological potential of Delftia sp. JD2 by a genomic approach

    Directory of Open Access Journals (Sweden)

    María A. Morel

    2016-04-01

    Full Text Available Delftia sp. JD2 is a chromium-resistant bacterium that reduces Cr(VI to Cr(III, accumulates Pb(II, produces the phytohormone indole-3-acetic acid and siderophores, and increases the plant growth performance of rhizobia in co-inoculation experiments. We aimed to analyze the biotechnological potential of JD2 using a genomic approach. JD2 has a genome of 6.76Mb, with 6,051 predicted protein coding sequences and 93 RNA genes (tRNA and rRNA. The indole-acetamide pathway was identified as responsible for the synthesis of indole-3-acetic acid. The genetic information involved in chromium resistance (the gene cluster, chrBACF, was found. At least 40 putative genes encoding for TonB-dependent receptors, probably involved in the utilization of siderophores and biopolymers, and genes for the synthesis, maturation, exportation and uptake of pyoverdine, and acquisition of Fe-pyochelin and Fe-enterobactin were also identified. The information also suggests that JD2 produce polyhydroxybutyrate, a carbon reserve polymer commonly used for manufacturing petrochemical free bioplastics. In addition, JD2 may degrade lignin-derived aromatic compounds to 2-pyrone-4,6-dicarboxylate, a molecule used in the bio-based polymer industry. Finally, a comparative genomic analysis of JD2, Delftia sp. Cs1-4 and Delftia acidovorans SPH-1 is also discussed. The present work provides insights into the physiology and genetics of a microorganism with many potential uses in biotechnology.

  16. Acrylamide-functionalized graphene micro-solid-phase extraction coupled to high-performance liquid chromatography for the online analysis of trace monoamine acidic metabolites in biological samples.

    Science.gov (United States)

    Yang, Xiaoting; Hu, Yufei; Li, Gongke; Zhang, Zhuomin

    2015-05-01

    Monoamine acidic metabolites in biological samples are essential biomarkers for the diagnosis of neurological disorders. In this work, acrylamide-functionalized graphene adsorbent was successfully synthesized by a chemical functionalization method and was packed in a homemade polyether ether ketone micro column as a micro-solid-phase extraction unit. This micro-solid-phase extraction unit was directly coupled to high-performance liquid chromatography to form an online system for the separation and analysis of three monoamine acidic metabolites including homovanillic acid, 5-hydroxyindole-3-acetic acid, and 3,4-dihydroxyphenylacetic acid in human urine and plasma. The online system showed high stability, permeability, and adsorption capacity toward target metabolites. The saturated extraction amount of this online system was 213.1, 107.0, and 153.4 ng for homovanillic acid, 5-hydroxyindole-3-acetic acid, and 3,4-dihydroxyphenylacetic acid, respectively. Excellent detection limits were achieved in the range of 0.08-0.25 μg/L with good linearity and reproducibility. It was interesting that three targets in urine and plasma could be actually quantified to be 0.94-3.93 μg/L in plasma and 7.15-19.38 μg/L in urine. Good recoveries were achieved as 84.8-101.4% for urine and 77.8-95.1% for plasma with the intra- and interday relative standard deviations less than 9.3 and 10.3%, respectively. This method shows great potential for online analysis of trace monoamine acidic metabolites in biological samples.

  17. Aminopropyl-modified mesoporous molecular sieves as efficient adsorbents for removal of auxins

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, Michał, E-mail: michal.moritz@put.poznan.pl [Poznan University of Technology, Faculty of Chemical Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, 60-965 Poznań (Poland); Geszke-Moritz, Małgorzata, E-mail: Malgorzata.Geszke-Moritz@amu.edu.pl [NanoBioMedical Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland)

    2015-03-15

    Graphical abstract: Adsorption of indole-3-acetic acid (IAA) on aminopropyl-modified mesoporous sieves. - Highlights: • Four types of mesoporous molecular sieves were used as sorbents for removal of auxins. • SBA-15, MCF, PHTS and SBA-16 were grafted with (3-aminopropyl)triethoxysilane. • The adsorption capacity of modified materials was higher as compared to pure silicas. • Surface modification and pore volume play important role in adsorption process. - Abstract: In the present study, mesoporous siliceous materials grafted with 3-aminopropyltriethoxysilane (APTES) were examined as sorbents for removal of chosen plant growth factors (auxins) such as 1-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). Four different types of mesoporous molecular sieves including SBA-15, PHTS, SBA-16 and MCF have been prepared via non-ionic surfactant-assisted soft templating method. Silica molecular sieves were thoroughly characterized by nitrogen adsorption–desorption analysis, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The maximum adsorption capacity (Q{sub max}) for NAA, IAA and IBA was in the range from 51.0 to 140.8 mg/g and from 4.3 to 7.3 mg/g for aminopropyl-modified adsorbents and pure silicas, respectively. The best adsorption performance was observed for IAA entrapment using both APTES-functionalized SBA-15 and MCF matrices (Q{sub max} of 140.8 and 137.0 mg/g, respectively) which can be ascribed to their larger pore volumes and pore diameters. Moreover, these silicas were characterized by the highest adsorption efficiency exceeding 90% at low pollutant concentration. The experimental points for adsorption of plant growth factors onto aminopropyl-modified mesoporous molecular sieves fitted well to the Langmuir equation.

  18. Effect of different plant growth regulators on micro-tuber induction and plant regeneration of Pinellia ternate (Thunb) Briet.

    Science.gov (United States)

    Wang, Junli; Wang, Qian; Wang, Jue; Lu, Yuan; Xiao, Xuan; Gong, Weizhen; Liu, Jikai

    2009-10-01

    An efficient micropropagation system for Pinellia ternate (Thunb) Briet, a traditional Chinese medicinal plant, has been developed. Petiole and lamina of P. ternate were used as explants and cultured on Murashige and Skoog (MS) medium containing different concentrations of different plant growth regulators. The results indicated that low concentration of 2,4-dicholorophenoxy acetic acid (2,4-D), indole-3-acetic acid (IAA) and α-naphthalene acetic acid (NAA) were suitable for micro-tuber induction, but callus induction rate increased with increasing concentrations of growth regulators. Tubers induction rates of petiole and leaf were (81.8 %-100 %) and (89.4 %-96.0 %) respectively, when 0.2 mg l(-1) 2, 4-dicholorophenoxy acetic acid, indole-3-acetic acid or α-naphthalene acetic acid were present in the medium. Tubers induction rates of petiole and leaf cultured on MS medium supplemented with 0.2-0.5 mg l(-1) 6-benzyl amino purine (6-BAP) were (94.1 %-100 %) and (96.0 %-100 %) respectively. When the concentration of 2,4-dicholorophenoxy acetic acid, α-naphthalene acetic acid and 6-benzyl amino purine was increased to 2.0 mg l(-1), callus induction rates of petiole and leaf were 100 % and 98.2 %, 91.0 % and 36.0 %, 62.3 % and 70.0 %, respectively. Different concentration of kinetin (KT) and zeatin (ZT) had no significant effect on micro-tuber induction of petiole. Most petioles showed polarity during the cultivation of explants, when supplemented with different concentrations of auxin or cytokinin in the MS medium.

  19. Transport and metabolism of indole-3-acetyl-myo-inositol-galactoside in seedlings of Zea mays

    Science.gov (United States)

    Komoszynski, M.; Bandurski, R. S.

    1986-01-01

    Indole-3-acetyl-myo-inositol galactoside labeled with 3H in the indole and 14C in the galactose moieties was applied to kernels of 5 day old germinating seedlings of Zea mays. Indole-3-acetyl-myo-inositol galactoside was not transported into either the shoot or root tissue as the intact molecule but was instead hydrolyzed to yield [3H]indole-3-acetyl-myo-inositol and [3H]indole-3-acetic acid which were then transported to the shoot with little radioactivity going to the root. With certain assumption concerning the equilibration of applied [3H]indole-3-acetyl-myo-inositol-[U-14C]galactose with the endogenous pool, it may be concluded that indole-3-acetyl-myo-inositol galactoside in the endosperm supplies about 2 picomoles per plant per hour of indole-3-acetyl-myo-inositol and 1 picomole per plant per hour of indole-3-acetic acid to the shoot and thus is comparable to indole-3-acetyl-myo-inositol as a source of indole-acetic acid for the shoot. Quantitative estimates of the amount of galactose in the kernels suggest that [3H]indole-3-acetyl-myo-inositol-[14C]galactose is hydrolyzed after the compound leaves the endosperm but before it reaches the shoot. In addition, [3H]indole-3-acetyl-myo-inositol-[14C]galactose supplies appreciable amounts of 14C to the shoot and both 14C and 3H to an uncharacterized insoluble fraction of the endosperm.

  20. Effects of bioactive compounds from carrots (Daucus carota L.), polyacetylenes, beta-carotene and lutein on human lymphoid leukaemia cells.

    Science.gov (United States)

    Zaini, Rana G; Brandt, Kirsten; Clench, Malcolm R; Le Maitre, Christine L

    2012-07-01

    New therapies for leukaemia are urgently needed. Carrots have been suggested as a potential treatment for leukaemia in traditional medicine and have previously been studied in other contexts as potential sources of anticancer agents. Indicating that carrots may contain bioactive compounds, which may show potential in leukaemia therapies. This study investigated the effects of five fractions from carrot juice extract (CJE) on human lymphoid leukaemia cell lines, together with five purified bioactive compounds found in Daucus carota L, including: three polyacetylenes (falcarinol, falcarindiol and falcarindiol-3-acetate) and two carotenoids (beta-carotene and lutein). Their effects on induction of apoptosis using Annexin V/PI and Caspase 3 activity assays analysed via flow cytometry and inhibition of cellular proliferation using Cell Titer Glo assay and cell cycle analysis were investigated. Treatment of all three lymphoid leukaemia cell lines with the fraction from carrot extracts which contained polyacetylenes and carotenoids was significantly more cytotoxic than the 4 other fractions. Treatments with purified polyacetylenes also induced apoptosis in a dose and time responsive manner. Moreover, falcarinol and falcarindiol-3-acetate isolated from Daucus carota L were more cytotoxic than falcarindiol. In contrast, the carotenoids showed no significant effect on either apoptosis or cell proliferation in any of the cells investigated. This suggests that polyacetylenes rather than beta-carotene or lutein are the bioactive components found in Daucus carota L and could be useful in the development of new leukemic therapies. Here, for the first time, the cytotoxic effects of polyacetylenes have been shown to be exerted via induction of apoptosis and arrest of cell cycle.

  1. Characterisation of polyacetylenes isolated from carrot (Daucus carota) extracts by negative ion tandem mass spectrometry.

    Science.gov (United States)

    Rai, Dilip K; Brunton, Nigel P; Koidis, Anastasios; Rawson, Ashish; McLoughlin, Padraig; Griffiths, William J

    2011-08-15

    The potential use of negative electrospray ionisation mass spectrometry (ESI-MS) in the characterisation of the three polyacetylenes common in carrots (Daucus carota) has been assessed. The MS scans have demonstrated that the polyacetylenes undergo a modest degree of in-source decomposition in the negative ionisation mode while the positive ionisation mode has shown predominantly sodiated ions and no [M+H](+) ions. Tandem mass spectrometric (MS/MS) studies have shown that the polyacetylenes follow two distinct fragmentation pathways: one that involves cleavage of the C3-C4 bond and the other with cleavage of the C7-C8 bond. The cleavage of the C7-C8 bond generated product ions m/z 105.0 for falcarinol, m/z 105/107.0 for falcarindiol, m/z 147.0/149.1 for falcarindiol-3-acetate. In addition to these product ions, the transitions m/z 243.2 → 187.1 (falcarinol), m/z 259.2 → 203.1 (falcarindiol), m/z 301.2 → 255.2/203.1 (falcarindiol-3-acetate), mostly from the C3-C4 bond cleavage, can form the basis of multiple reaction monitoring (MRM)-quantitative methods which are poorly represented in the literature. The 'MS(3) ' experimental data confirmed a less pronounced homolytic cleavage site between the C11-C12 bond in the falcarinol-type polacetylenes. The optimised liquid chromatography (LC)/MS conditions have achieved a baseline chromatographic separation of the three polyacetylenes investigated within 40 min total run-time.

  2. Effect of succinate on phosphate solubilization in nitrogen fixing bacteria harbouring chick pea and their effect on plant growth.

    Science.gov (United States)

    Iyer, Bhagya; Rajput, Mahendrapal Singh; Rajkumar, Shalini

    2017-09-01

    Diverse nitrogen fixing bacteria harbouring chick pea rhizosphere and root nodules were tested for multiple plant growth promoting traits like tricalcium phosphate (TCP) and rock phosphate (RP) solubilization, production of ammonia, indole 3-acetic acid, chitinase, phytase and alkaline phosphatase. Isolates belonged to diverse genus like Enterobacter, Acinetobacter, Erwinia, Pseudomonas, Rhizobium, Sinorhizobium, Ensifer, Klebsiella, etc. Most isolates solubilized TCP and RP along with the lowering of media pH, indicating acidification to be the chief mechanism behind this solubilization. However, lowering of media pH and P release decreased by 32-100% when media was supplemented with succinate, a major component of plant root exudates indicating succinate mediated repression of P solubilization. Maximum TCP and RP solubilization with P release of 850μg/mL and 2088μg/mL was obtained with lowering of media pH up to 2.8 and 3.3 for isolate E43 and PSB1 respectively. This pH drop changed to 4.4 and 4.8 with 80% and 87% decrease in P solubilization in the presence of succinate. Maximum 246μg/mL indole 3-acetic acid production in Lh3, 44.8U/mL chitinase activity in MB3, 11.3U/mL phytase activity in I91 and 9.4U/mL alkaline phosphatase activity in SM1 were also obtained. Most isolates showed multiple PGP traits which resulted in significant plant growth promotion of chick pea plants. Present study shows repression of P solubilization by succinate for various bacterial groups which might be one of the reasons why phosphate solubilizing bacteria which perform well in vitro often fail in vivo. Studying this repression mechanism might be critical in understanding the in vivo efficacy. Copyright © 2017. Published by Elsevier GmbH.

  3. Species differences in ligand specificity of auxin-controlled elongation and auxin transport: comparing Zea and Vigna

    Science.gov (United States)

    Zhao, Hu; Hertel, Rainer; Ishikawa, Hideo; Evans, Michael L.

    2002-01-01

    The plant hormone auxin affects cell elongation in both roots and shoots. In roots, the predominant action of auxin is to inhibit cell elongation while in shoots auxin, at normal physiological levels, stimulates elongation. The question of whether the primary receptor for auxin is the same in roots and shoots has not been resolved. In addition to its action on cell elongation in roots and shoots, auxin is transported in a polar fashion in both organs. Although auxin transport is well characterized in both roots and shoots, there is relatively little information on the connection, if any, between auxin transport and its action on elongation. In particular, it is not clear whether the protein mediating polar auxin movement is separate from the protein mediating auxin action on cell elongation or whether these two processes might be mediated by one and the same receptor. We examined the identity of the auxin growth receptor in roots and shoots by comparing the response of roots and shoots of the grass Zea mays L. and the legume Vigna mungo L. to indole-3-acetic acid, 2-naphthoxyacetic acid, 4,6-dichloroindoleacetic acid, and 4,7-dichloroindoleacetic acid. We also studied whether or not a single protein might mediate both auxin transport and auxin action by comparing the polar transport of indole-3-acetic acid and 2-naphthoxyacetic acid through segments from Vigna hypocotyls and maize coleoptiles. For all of the assays performed (root elongation, shoot elongation, and polar transport) the action and transport of the auxin derivatives was much greater in the dicots than in the grass species. The preservation of ligand specificity between roots and shoots and the parallels in ligand specificity between auxin transport and auxin action on growth are consistent with the hypothesis that the auxin receptor is the same in roots and shoots and that this protein may mediate auxin efflux as well as auxin action in both organ types.

  4. Expression profile of PIN, AUX/LAX and PGP auxin transporter gene families in Sorghum bicolor under phytohormone and abiotic stress.

    Science.gov (United States)

    Shen, ChenJia; Bai, YouHuang; Wang, SuiKang; Zhang, SaiNa; Wu, YunRong; Chen, Ming; Jiang, DeAn; Qi, YanHua

    2010-07-01

    Auxin is transported by the influx carriers auxin resistant 1/like aux1 (AUX/LAX), and the efflux carriers pin-formed (PIN) and P-glycoprotein (PGP), which play a major role in polar auxin transport. Several auxin transporter genes have been characterized in dicotyledonous Arabidopsis, but most are unknown in monocotyledons, especially in sorghum. Here, we analyze the chromosome distribution, gene duplication and intron/exon of SbPIN, SbLAX and SbPGP gene families, and examine their phylogenic relationships in Arabidopsis, rice and sorghum. Real-time PCR analysis demonstrated that most of these genes were differently expressed in the organs of sorghum. SbPIN3 and SbPIN9 were highly expressed in flowers, SbLAX2 and SbPGP17 were mainly expressed in stems, and SbPGP7 was strongly expressed in roots. This suggests that individual genes might participate in specific organ development. The expression profiles of these gene families were analyzed after treatment with: (a) the phytohormones indole-3-acetic acid and brassinosteroid; (b) the polar auxin transport inhibitors 1-naphthoxyacetic acids, 1-naphthylphthalamic acid and 2,3,5-triiodobenzoic acid; and (c) abscissic acid and the abiotic stresses of high salinity and drought. Most of the auxin transporter genes were strongly induced by indole-3-acetic acid and brassinosteroid, providing new evidence for the synergism of these phytohormones. Interestingly, most genes showed similar trends in expression under polar auxin transport inhibitors and each also responded to abscissic acid, salt and drought. This study provides new insights into the auxin transporters of sorghum.

  5. The volatile profiles of a rare apple (Malus domestica Borkh.) honey: shikimic acid-pathway derivatives, terpenes, and others.

    Science.gov (United States)

    Kuś, Piotr Marek; Jerković, Igor; Tuberoso, Carlo Ignazio Giovanni; Šarolić, Mladenka

    2013-09-01

    The volatile profiles of rare Malus domestica Borkh. honey were investigated for the first time. Two representative samples from Poland (sample I) and Spain (sample II) were selected by pollen analysis (44-45% of Malus spp. pollen) and investigated by GC/FID/MS after headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE). The apple honey is characterized by high percentage of shikimic acid-pathway derivatives, as well as terpenes, norisoprenoids, and some other compounds such as coumaran and methyl 1H-indole-3-acetate. The main compounds of the honey headspace were (sample I; sample II): benzaldehyde (9.4%; 32.1%), benzyl alcohol (0.3%; 14.4%), hotrienol (26.0%, 6.2%), and lilac aldehyde isomers (26.3%; 1.7%), but only Spanish sample contained car-2-en-4-one (10.2%). CH2 Cl2 and pentane/Et2 O 1 : 2 (v/v) were used for USE. The most relevant compounds identified in the extracts were: benzaldehyde (0.9-3.9%), benzoic acid (2.0-11.2%), terpendiol I (0.3-7.4%), coumaran (0.0-2.8%), 2-phenylacetic acid (2.0-26.4%), methyl syringate (3.9-13.1%), vomifoliol (5.0-31.8%), and methyl 1H-indole-3-acetate (1.9-10.2%). Apple honey contained also benzyl alcohol, 2-phenylethanol, (E)-cinnamaldehyde, (E)-cinnamyl alcohol, eugenol, vanillin, and linalool that have been found previously in apple flowers, thus disclosing similarity of both volatile profiles.

  6. Agrobacterium tumefaciens – Mediated transformation of Woodfordia fruticosa (L. Kurz

    Directory of Open Access Journals (Sweden)

    Mallesham Bulle

    2015-12-01

    Full Text Available In the present study, a protocol for Agrobacterium tumefaciens-mediated transformation has been optimized for Woodfordia fruticosa (L. Kurz. Precultured axenic leaf segments were co-cultivated with A. tumefaciens strain LBA4404 harboring the binary plasmid pCAMBIA1301 with β-glucuronidase (uidA containing intron as the reporter gene and hygromycin phosphotransferase (hpt as a selectable marker gene. After 3 days of co-cultivation, leaf segments were cultured on MS medium containing Thidiazuron (TDZ 4.54 μM and Indole-3-acetic acid IAA (1.14 μM + 20 mg/l hygromycin + 200 mg/l cefotaxime (PTSM1 for 4 weeks (includes a single subculture onto the same medium at a 2 week interval. They were subsequently cultured for 3 weeks on MS medium containing Thidiazuron (TDZ 4.54 μM and Indole-3-acetic acid IAA (1.14 μM + 25 mg/l hygromycin + 100 mg/l cefotaxime (PTSM2 medium for further development and shoot elongation. The hygromycin resistant shoots were rooted on a rooting medium (PTRM containing half strength MS medium + 4.90 μM IBA + 25 mg/l hygromycin. A highest transformation efficiency of 44.5% with a mean number of 2.6 transgenic shoots per explant was achieved. Successful transformation was confirmed by the histochemical GUS activity of the regenerated shoots, PCR and RT-PCR analysis using respective primers. Southern blot analysis revealed that the hpt gene integrated into the genome of transgenic W. fruticosa. Establishment of genetic transformation protocol may facilitate the improvement of this medicinal plant in terms of enhancement of secondary metabolites.

  7. Synthesis and antimicrobial activities of dehydroepiandrosterone oxime acetate%醋酸去氢表雄酮肟的合成及其抗菌活性研究

    Institute of Scientific and Technical Information of China (English)

    田光辉

    2012-01-01

    以醋酸去氢表雄酮为原料,室温搅拌下和盐酸羟胺在弱碱性介质中反应合成醋酸去氢表雄酮肟,得到了纯度较高的醋酸去氢表雄酮肟,收率达89.6%.通过测定其熔点,借助紫外光谱(UV)、红外光谱(IR)、核磁共振谱( NMR)、质谱(MS)以及元素分析等技术来表征其结构.抗菌活性实验表明,醋酸去氢表雄酮肟对实验菌株均有抑制和灭活作用,对枯草芽胞杆菌CMCC63501株的作用表现得更为明显.%The target compound 3-β-hydroxy-deoxyandrost-5-ene-17-one oxime-3-acetate was synthesized in alkalescence medium with 3-β-hydroxy-deoxyandrost-5-ene-17-one-3-acetate and hydroxyla-mine hydrochloride at room temperature by churn-dasher, purer dehydroepiandrosterone oxime acetate was obtained and its yield reached 89. 6%. The melting point of this target compound was determined and its structure was fully characterized by UV, IR, NMR, MS and elemental analysis. The antimicrobial activities of dehydroepiandrosterone oxime acetate was evaluated by inhibiting the growth of four bacteria. The results showed that the target compound inhibited the growth of testing bacteria and sterilized them, and showed higher antimicrobial activity especially against bacillus subtillis CMCC63S01.

  8. Influence of the kind of peat and the depth of sampling on the biochemical properties of Tagan peatland

    Science.gov (United States)

    Wojciech Szajdak, Lech; Inisheva, Lydia I.

    2010-05-01

    The upper layer of a peat bog in which organic matter decomposes aerobically much more rapidly than in the underlying, anaerobic catotelm. As litter accumulates at the surface the size of the catotelm increases, because the thickness of the acrotelm is limited to depth at which aerobic respiration can occur. Although the rate of decomposition per unit volume of material is much greater in the acrotelm than in the catotelm, a point is reached at which the difference in volume between the two layers is such that the total rate of decomposition in the catotelm is equal to that in the acrotelm. This limits the thickness to which the bog can grow. Should there be a climate change (e.g. an increase in precipitation) growth can resume. Bogs therefore preserve a record of climatic conditions. Soils samples were taken from four places marked as No 1, 2, 3 and 4 each from two depth 0-25 and 50-75 cm of the peatland Tagan. Peatlands Tagan is located near Tomsk, West Siberia, Russia. Place No 1 in both layers represents grasses peat with the degree of the decomposition ranged from 25 to 35% (pH 6.31-7.95). Point 2 is characterized by wooden and wooden grasses peat with 35% degree of the decomposition (pH 5.16-9.31. There is buckbean peat in the points 3 and 4 (pH 6.4-6.49). However, 1.5 m depth of sapropel is located in point 4. The activity of the following enzymes: xanthine oxidase, phenolic oxidase, peroxidase, urease, nitrate reductase were measured and two forms of organic carbon (total organic carbon and dissolved organic carbon) and two form of iron Fe(II) and Fe(III) were determined in these samples. These enzymes participate in several biochemical pathways in soil connected with redox potential. The concentrations of indole-3-acetic acid, very famous fitohormone were also measured. It was observed in all places of sampling significant increase of the total organic carbon with an increase of the depth. However, the quantity of dissolved organic carbon closely decreased

  9. 萜类化合物对德国小蠊驱避活性的研究%Repellent activity evaluation of terpenoids against German cockroaches

    Institute of Scientific and Technical Information of China (English)

    韩招久; 王宗德; 姜志宽; 钱万红; 陈金珠; 郑卫青

    2012-01-01

    Objective To screen and evaluate the repellent activity of terpenoids compounds isolated or synthesized from turpentine against adult male German cockroaches(Blattella germanica). Methods Bioassay with dipped filter papers. Results Among those 43 terpenoids compounds, four compounds, namely hydroxycitronellal, menthol, hydroxy-citronellal propionate and campholenic aldehyde propylene glycol 1,3 - acetal displayed the most powerful activity in the preliminary screening test using dipped filter paper at the dose of 340 礸/cm2. Further test with geometric series doses for the RD50s (dose of 50% repellency) reveal that the RD50s were 154. 7, 56. 2, 165. 9 and 151. 3 礸/cm2 for hydroxycitronellal, menthol, hydroxycitronellal propionate and campholenic aldehyde propylene glycol 1,3?acetal respectively, less than diethyltoluamide (DEET) with the RD50 of 194.5 礸/cm2. Conclusion It is supposed that these four terpenoids, hydroxycitronellal, menthol, hydroxycitronellal propionate and campholenic aldehyde propylene glycol 1 ,3 - acetal would be potential and promising cockroach repellents.%目的 筛选评估萜类化合物对德国小蠊的驱避活性.方法 滤纸浸液法生物测定.结果 43个萜类化合物在剂量为340 μg/cm2时对德国小蠊雄性成虫驱避活性的初步测试结果显示,羟基香茅醛、薄荷醇、羟基香茅醛丙酸酯、龙脑烯醛缩-1,3-丙二醇等4个化合物表现出了较高的驱避活性.对这4个化合物采用几何浓度梯度进一步测试,并与目前广泛应用的昆虫驱避剂避蚊胺(DEET)进行比较.羟基香茅醛、薄荷醇、羟基香茅醛丙酸酯、龙脑烯醛缩-1,3-丙二醇的驱避中量(RD50)分别为154.7、56.2、165.9和151.3μg/cm2,均低于DEET的RD50(194.5 μg/cm2).结论 本项研究结果说明,羟基香茅醛、薄荷醇、羟基香茅醛丙酸酯、龙脑烯醛缩-1,3-丙二醇具有作为蟑螂驱避剂的应用前景.

  10. Quorum Sensing Signaling Molecules Produced by Reference and Emerging Soft-Rot Bacteria (Dickeya and Pectobacterium spp.)

    Science.gov (United States)

    Crépin, Alexandre; Barbey, Corinne; Beury-Cirou, Amélie; Hélias, Valérie; Taupin, Laure; Reverchon, Sylvie; Nasser, William; Faure, Denis; Dufour, Alain; Orange, Nicole; Feuilloley, Marc; Heurlier, Karin; Burini, Jean-François; Latour, Xavier

    2012-01-01

    Background Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates. Methodology/Principal Findings Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase. Conclusions/Significance Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also differences in the

  11. THE USE OF gusA REPORTER GENE TO MONITOR THE SURVIVAL OF INTRODUCED BACTERIA IN THE SOIL

    Directory of Open Access Journals (Sweden)

    Edi Husen

    2013-07-01

    Full Text Available An effective marker to monitor the survival of introduced bacteria in the soil is required for further evaluation of their beneficial effects on plant growth. This study tested the use of gusA gene as a marker to trace the fate of three Gram negative bacteria in the root, rhizosphere, and soil. The study was conducted at the laboratory and greenhouse of the National Institute of Molecular Biology and Biotechnology, Philippines from January to December 2001. Isolates TCaR 61 and TCeRe 60, and Azotobacter vinelandii Mac 259 were selected as test bacteria based on their ability to produce indole-3acetic acid and solubilize precipitated phosphate, which may promote plant growth in the field. These bacteria were marked with gusA reporter gene from Escherichia coli strain S17-1(λ-pir containing mTn5SSgusA21. The gusA (β-glucuronidase gene from the donor (E. coli was transferred to each bacterium (recipient through bacterial conjugation in mating procedures using tryptone-yeast agar followed by the selection of the transconjugants (bacteria receiving gusA in tryptone-yeast agar supplemented with double antibiotics and X-GlcA (5bromo-4chloro- 3indoxyl-β-D-glucuronic acid. The antibiotics used were rifampicin and either streptomycin or spectinomycin based on antibiotic profiles of the donor and recipients. The results showed that the insertion of gusA gene into bacterial genomes of the recipient did not impair its phenotypic traits; the growth rates of the transconjugants as well as their ability to produce indole-3acetic acid and solubilize precipitated phosphate in pure culture were similar to their wild types. All transconjugants colonized the roots of hot pepper (Capsicum annuum L. and survived in the rhizosphere and soil until the late of vegetative growth stage. The distinct blue staining of transconjugants as the expression of gusA gene in media containing X-GlcA coupled with their resistance to rifampicin and streptomycin or spectinomycin

  12. Gas and particle emissions from Soufrière Hills Volcano, Montserrat, West Indies: characterization and health hazard assessment

    Science.gov (United States)

    Allen, Andrew G.; Baxter, Peter J.; Ottley, Christopher J.

    The Soufrière Hills Volcano, Montserrat, erupting since 18 July 1995, intensified its degassing in early 1996 with the continuing growth of the lava dome inside the summit crater. During this period of increased activity, between 11 and 18 March 1996, we measured gases and particles within the visible plume to determine whether at that time it posed a health risk to the population of Plymouth, the capital town, which is 5km southwest (downwind) and was then still occupied. Gravimetric measurements were made of total suspended particles (TSP) and particles having an aerodynamic diameter of less than 10μm (PM10). Measurements were made of sulphur dioxide (SO2), hydrochloric acid (HCl), hydrofluoric acid (HF), nitric acid (HNO3), acetic acid (CH3COOH), formic acid (HCOOH), and particulate sulphate (SO42-), chloride (Cl-), nitrate (NO3-), fluoride (F-), methanesulphonate (CH3SO3-), acetate (CH3COO-), formate (HCOO-), ammonium (NH4+), sodium (Na+) and acidity (H+). Trace metals having human health implications [chromium (Cr), nickel (Ni), cobalt (Co), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), tin (Sn), mercury (Hg) and lead (Pb)] were also determined. Mean concentrations of HCl, SO2 and HF obtained in the town of Plymouth were 14.0, 5.9 and 0.8ppbv, respectively. Corresponding concentrations in the mixed plume on the crater edge were 533, 168 and 22ppbv. There were no direct emissions of HNO3, although nitrate was detected in coarse particles at the source. Higher concentrations of CH3COOH and HCOOH were measured close to the crater. Mean TSP and PM10 were 64 and 15μgm-3 in Plymouth, and 455 and 47μgm-3 on the upper volcano slope. Aerosols were highly acidic at the source but rapidly neutralised during transport. Trace metals were enriched in the aerosol relative to crater surface material. The concentrations of the acid gases, sulphur dioxide in particular, and particles were found to be too small to pose a health hazard at the time of

  13. Elicitation of Phenolics from the Micropropagated Endangered Medicinal Plant Calligonum polygonoides L. (Polygonoaceae)

    Science.gov (United States)

    Owis, Asmaa I.; Abdelwahab, Nada S.; Abul-Soad, Adel A.

    2016-01-01

    Background: Calligonum polygonoides L. subsp. comosum (L’Hér.) Sosk. is a plant species belonging to family Polygonaceae. Susceptibility to threaten, presence of various chemical constituents, and many medicinal effects reported for this plant in addition to rareness of in vitro culture studies have fuelled the need for its micropropagation and phytochemical investigations of the produced cultures. Objectives: To employ in vitro culture technique for ex situ conservation of C. polygonoides, using the fruit as an explant; establish callus and cell suspension cultures from in vitro germinated plantlets; investigate the production of phenolics through callus, redifferentiated shoot, and cell suspension cultures; attempt to enhance cell capacity to accumulate phenolics using salicylic acid and yeast extract and provide a brief demonstration of biosynthetic pathway leading to phenolic production. Materials and Methods: Modified Murashige and Skoog media supplemented with growth hormones such as kinetin, 1-naphthaleneacetic acid, 6-benzylaminopurine, and indole-3-acetic acid were used to establish callus, redifferentiated shoots, and cell suspension cultures. Elicitation of cell suspension culture was performed using salicylic acid and yeast extracts. A reversed phase-high performance liquid chromatography method for determination of phenolic content in the aforementioned cultures was developed. Results: The unorganized callus and cell suspension cultures contained fewer amounts of phenolic compounds than redifferentiated shoots. Elicitation produced massive quantitative reprogramming of phenolic content. Conclusion: The present study offers an alternative and renewable source for this valuable natural plant, provide a chance to improve secondary metabolite yield and serve as a useful tool for studying the biosynthesis of these compounds and its regulation in plant cells. SUMMARY In vitro culture techniques provided a strategy for ex situ conservation of the

  14. Cerebral Metabolic Profiling of Hypothermic Circulatory Arrest with and Without Antegrade Selective Cerebral Perfusion: Evidence from Nontargeted Tissue Metabolomics in a Rabbit Model

    Institute of Scientific and Technical Information of China (English)

    Li-Hua Zou; Jin-Ping Liu; Hao Zhang; Shu-Bin Wu; Bing-Yang Ji

    2016-01-01

    Background:Antegrade selective cerebral perfusion (ASCP) is regarded to perform cerebral protection during the thoracic aorta surgery as an adjunctive technique to deep hypothermic circulatory arrest (DHCA).However,brain metabolism profile after ASCP has not been systematically investigated by metabolomics technology.Methods:To clarify the metabolomics profiling of ASCP,12 New Zealand white rabbits were randomly assigned into 60 min DHCA with (DHCA+ASCP [DA] group,n =6) and without (DHCA [D] group,n =6) ASCP according to the random number table.ASCP was conducted by cannulation on the right subclavian artery and cross-clamping of the innominate artery.Rabbits were sacrificed 60 min after weaning off cardiopulmonary bypass.The metabolic features of the cerebral cortex were analyzed by a nontargeted metabolic profiling strategy based on gas chromatography-mass spectrometry.Variable importance projection values exceeding 1.0 were selected as potentially changed metabolites,and then Student's t-test was applied to test for statistical significance between the two groups.Results:Metabolic profiling of brain was distinctive significantly between the two groups (Q2y =0.88 for partial least squares-DA model).In comparing to group D,62 definable metabolites were varied significantly after ASCP,which were mainly related to amino acid metabolism,carbohydrate metabolism,and lipid metabolism.Kyoto Encyclopedia of Genes and Genomes analysis revealed that metabolic pathways after DHCA with ASCP were mainly involved in the activated glycolytic pathway,subdued anaerobic metabolism,and oxidative stress.In addition,L-kynurenine (P =0.0019),5-methoxyindole-3-acetic acid (P =0.0499),and 5-hydroxyindole-3-acetic acid (P =0.0495) in tryptophan metabolism pathways were decreased,and citrulline (P =0.0158) in urea cycle was increased in group DA comparing to group D.Conclusions:The present study applied metabolomics analysis to identify the cerebral metabolic profiling in rabbits with ASCP

  15. Quorum sensing signaling molecules produced by reference and emerging soft-rot bacteria (Dickeya and Pectobacterium spp..

    Directory of Open Access Journals (Sweden)

    Alexandre Crépin

    Full Text Available BACKGROUND: Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates. METHODOLOGY/PRINCIPAL FINDINGS: Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase. CONCLUSIONS/SIGNIFICANCE: Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also

  16. In Vitro and In Vivo Plant Growth Promoting Activities and DNA Fingerprinting of Antagonistic Endophytic Actinomycetes Associates with Medicinal Plants.

    Science.gov (United States)

    Passari, Ajit Kumar; Mishra, Vineet Kumar; Gupta, Vijai Kumar; Yadav, Mukesh Kumar; Saikia, Ratul; Singh, Bhim Pratap

    2015-01-01

    Endophytic actinomycetes have shown unique plant growth promoting as well as antagonistic activity against fungal phytopathogens. In the present study forty-two endophytic actinomycetes recovered from medicinal plants were evaluated for their antagonistic potential and plant growth-promoting abilities. Twenty-two isolates which showed the inhibitory activity against at least one pathogen were subsequently tested for their plant-growth promoting activities and were compared genotypically using DNA based fingerprinting, including enterobacterial repetitive intergenic consensus (ERIC) and BOX repetitive elements. Genetic relatedness based on both ERIC and BOX-PCR generates specific patterns corresponding to particular genotypes. Exponentially grown antagonistic isolates were used to evaluate phosphate solubilization, siderophores, HCN, ammonia, chitinase, indole-3-acetic acid production, as well as antifungal activities. Out of 22 isolates, the amount of indole-3-acetic acid (IAA) ranging between 10-32 μg/ml was produced by 20 isolates and all isolates were positive for ammonia production ranging between 5.2 to 54 mg/ml. Among 22 isolates tested, the amount of hydroxamate-type siderophores were produced by 16 isolates ranging between 5.2 to 36.4 μg/ml, while catechols-type siderophores produced by 5 isolates ranging from 3.2 to 5.4 μg/ml. Fourteen isolates showed the solubilisation of inorganic phosphorous ranging from 3.2 to 32.6 mg/100ml. Chitinase and HCN production was shown by 19 and 15 different isolates, respectively. In addition, genes of indole acetic acid (iaaM) and chitinase (chiC) were successively amplified from 20 and 19 isolates respectively. The two potential strains Streptomyces sp. (BPSAC34) and Leifsonia xyli (BPSAC24) were tested in vivo and improved a range of growth parameters in chilli (Capsicum annuum L.) under greenhouse conditions. This study is the first published report that actinomycetes can be isolated as endophytes from within these

  17. In Vitro and In Vivo Plant Growth Promoting Activities and DNA Fingerprinting of Antagonistic Endophytic Actinomycetes Associates with Medicinal Plants.

    Directory of Open Access Journals (Sweden)

    Ajit Kumar Passari

    Full Text Available Endophytic actinomycetes have shown unique plant growth promoting as well as antagonistic activity against fungal phytopathogens. In the present study forty-two endophytic actinomycetes recovered from medicinal plants were evaluated for their antagonistic potential and plant growth-promoting abilities. Twenty-two isolates which showed the inhibitory activity against at least one pathogen were subsequently tested for their plant-growth promoting activities and were compared genotypically using DNA based fingerprinting, including enterobacterial repetitive intergenic consensus (ERIC and BOX repetitive elements. Genetic relatedness based on both ERIC and BOX-PCR generates specific patterns corresponding to particular genotypes. Exponentially grown antagonistic isolates were used to evaluate phosphate solubilization, siderophores, HCN, ammonia, chitinase, indole-3-acetic acid production, as well as antifungal activities. Out of 22 isolates, the amount of indole-3-acetic acid (IAA ranging between 10-32 μg/ml was produced by 20 isolates and all isolates were positive for ammonia production ranging between 5.2 to 54 mg/ml. Among 22 isolates tested, the amount of hydroxamate-type siderophores were produced by 16 isolates ranging between 5.2 to 36.4 μg/ml, while catechols-type siderophores produced by 5 isolates ranging from 3.2 to 5.4 μg/ml. Fourteen isolates showed the solubilisation of inorganic phosphorous ranging from 3.2 to 32.6 mg/100ml. Chitinase and HCN production was shown by 19 and 15 different isolates, respectively. In addition, genes of indole acetic acid (iaaM and chitinase (chiC were successively amplified from 20 and 19 isolates respectively. The two potential strains Streptomyces sp. (BPSAC34 and Leifsonia xyli (BPSAC24 were tested in vivo and improved a range of growth parameters in chilli (Capsicum annuum L. under greenhouse conditions. This study is the first published report that actinomycetes can be isolated as endophytes from

  18. Pollination-, development-, and auxin-specific regulation of gibberellin 3beta-hydroxylase gene expression in pea fruit and seeds.

    Science.gov (United States)

    Ozga, Jocelyn A; Yu, Jody; Reinecke, Dennis M

    2003-03-01

    To understand further how pollination, seeds, auxin (4-chloroindole-3-acetic acid [4-Cl-IAA]), and gibberellins (GAs) regulate GA biosynthesis in pea (Pisum sativum) fruit, we studied expression of the gene PsGA3ox1 that codes for the enzyme that converts GA(20) to biologically active GA(1) using real-time reverse transcription-polymerase chain reaction analysis. PsGA3ox1 mRNA levels were minimally detectable in prepollinated pericarps and ovules (-2 d after anthesis [DAA]), increased dramatically after pollination (0 DAA), then decreased by 1 DAA. Seed PsGA3ox1 mRNA levels increased at 4 DAA and again 8 to 12 DAA, when seed development was rapid. Pericarp PsGA3ox1 mRNA levels peaked coincidentally with rapid pod diameter expansion (6-10 DAA) to accommodate the growing seeds. The effects of seeds and hormones on the expression of pericarp PsGA3ox1 were investigated over a 24-h treatment period. Pericarp PsGA3ox1 mRNA levels gradually increased from 2 to 3 DAA when seeds were present; however, when the seeds were removed, the pericarp transcript levels dramatically declined. When 2-DAA deseeded pericarps were treated with 4-Cl-IAA, PsGA3ox1 mRNA levels peaked 4 h after hormone treatment (270-fold increase), then decreased. PsGA3ox1 mRNA levels in deseeded pericarps treated with indole-3-acetic acid or GA(3) were the same or lower than deseeded controls. These data show that PsGA3ox1 is expressed and developmentally regulated in pea pericarps and seeds. These data also show that pericarp PsGA3ox1 expression is hormonally regulated and suggest that the conversion of GA(20) to GA(1) occurs in the pericarp and is regulated by the presence of seeds and 4-Cl-IAA for fruit growth.

  19. Control of cytokinin and auxin homeostasis in cyanobacteria and algae.

    Science.gov (United States)

    Žižková, Eva; Kubeš, Martin; Dobrev, Petre I; Přibyl, Pavel; Šimura, Jan; Zahajská, Lenka; Záveská Drábková, Lenka; Novák, Ondřej; Motyka, Václav

    2017-01-01

    The metabolism of cytokinins (CKs) and auxins in vascular plants is relatively well understood, but data concerning their metabolic pathways in non-vascular plants are still rather rare. With the aim of filling this gap, 20 representatives of taxonomically major lineages of cyanobacteria and algae from Cyanophyceae, Xanthophyceae, Eustigmatophyceae, Porphyridiophyceae, Chlorophyceae, Ulvophyceae, Trebouxiophyceae, Zygnematophyceae and Klebsormidiophyceae were analysed for endogenous profiles of CKs and auxins and some of them were used for studies of the metabolic fate of exogenously applied radiolabelled CK, [(3)H]trans-zeatin (transZ) and auxin ([(3)H]indole-3-acetic acid (IAA)), and the dynamics of endogenous CK and auxin pools during algal growth and cell division. Quantification of phytohormone levels was performed by high-performance or ultrahigh-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-MS/MS, UHPLC-MS/MS). The dynamics of exogenously applied [(3)H]transZ and [(3)H]IAA in cell cultures were monitored by HPLC with on-line radioactivity detection. The comprehensive screen of selected cyanobacteria and algae for endogenous CKs revealed a predominance of bioactive and phosphate CK forms while O- and N-glucosides evidently did not contribute greatly to the total CK pool. The abundance of cis-zeatin-type CKs and occurrence of CK 2-methylthio derivatives pointed to the tRNA pathway as a substantial source of CKs. The importance of the tRNA biosynthetic pathway was proved by the detection of tRNA-bound CKs during the course of Scenedesmus obliquus growth. Among auxins, free IAA and its oxidation catabolite 2-oxindole-3-acetic acid represented the prevailing endogenous forms. After treatment with [(3)H]IAA, IAA-aspartate and indole-3-acetyl-1-glucosyl ester were detected as major auxin metabolites. Moreover, different dynamics of endogenous CKs and auxin profiles during S. obliquus culture clearly demonstrated diverse roles of both

  20. Photochemistry of 1,1,1-Trifluoroacetone on Rutile TiO2(110)

    Energy Technology Data Exchange (ETDEWEB)

    Zehr, Robert T.; Deskins, N. Aaron; Henderson, Michael A.

    2010-10-14

    The ultraviolet (UV) photon-induced photodecomposition of 1,1,1-trifluoroacetone (TFA) adsorbed on the rutile TiO2(110) surface has been investigated with photon stimulated desorption (PSD), temperature programmed desorption (TPD) and density functional theory (DFT). TFA adsorbed molecularly on the reduced surface (8% oxygen vacancies) in states desorbing below 300 K with trace thermal decomposition observed in TPD. Adsorption of TFA on a preoxidized TiO2(110) surface (accomplished by pre-exposure with 20 L O2) led to formation of a new TFA desorption state at 350 K, assigned to decomposition of a TFA-diolate species ((CF3)(CH3)COO). No TFA photochemistry was detected on the reduced surface. UV irradiation of TFA on the oxidized surface depleted TFA in the 350 K state, with TFA molecules in other TPD states unaffected. PSD measurements reveal that both carbonyl substituents (CH3 and CF3), as well as CO, were liberated during UV exposure at 95 K. Post-irradiation TPD showed evidence for both acetate (evolving as ketene at 650 K) and trifluoroacetate (evolving as CO2 at 600 K) as surface-bound photodecomposition products. The CO PSD product was not due to adsorbed CO, to mass spectrometer cracking of a CO-containing PSD product, or from background effects, but originated from complete fragmentation of an unidentified adsorbed TFA species. Thermodynamic analysis using DFT indicated that the photodecomposition of the TFA-diolate was likely not driven by thermodynamics alone as both pathways (CH3+trifluoroacetate and CF3+acetate) were detected when thermodynamics shows a clear preference for only one (CF3+acetate). These observations are in contrast to the photochemical behavior of acetone, butanone and acetaldehyde on TiO2(110), where only one of the two carbonyl substituent groups was observed, with a stoichiometric amount of carboxylate containing the other substituent left on the surface. We conclude that fluorination significantly alters the electronic structure of

  1. Fatty acid derivatives and dammarane triterpenes from the glandular trichome exudates of Ibicella lutea and Proboscidea louisiana.

    Science.gov (United States)

    Asai, Teigo; Hara, Noriyuki; Fujimoto, Yoshinori

    2010-06-01

    Ibicellalutea and Proboscidea louisiana, both of the Martyniaceae family, are known for rich glandular trichomes on their leaves and stems. Chemical investigations of the glandular trichome exudates on leaves of the two plants furnished three types of secondary metabolites, glycosylated fatty acids, glycerides (2-O-(3,6-diacetyloxyfattyacyl)glycerols and 2-O-(3-acetyloxyfattyacyl)glycerols) and dammarane triterpenes. The glycosylated fatty acids from I. lutea were determined to be 6(S)-(6-O-acetyl-beta-D-glucopyranosyloxy)-octadecanoic acid (1A), -eicosanoic acid (1B) and -docosanoic acid (1C), as well as their respective deacetyl congeners (2A, 2B and 2C), whereas P. louisiana furnished 8(S)-(6-O-acetyl-beta-D-glucopyranosyloxy)-eicosanoic acid (3A) and -docosanoic acid (3B) and their respective deacetyl congeners (4A and 4B), together with 2B. Both plants contained 12 identical 2-O-[(3R,6S)-3,6-diacetyloxyfattyacyl]glycerols (5A-L), in which the fatty acyl moieties contained between 17 and 21 carbon atoms. The corresponding mono-acetyloxy compounds, 2-O-[(3R)-3-acetyloxyfattyacyl]glycerols (6A-L) were detected in both plants. Among these glycerides, ten compounds (5A, 5C, 5F, 5H, 5K, 6A, 6C, 6F, 6H and 6K) had iso-fattyacyl structures and four (5E, 5J, 6E and 6J) had anteiso-fattyacyl structures. A previously unknown dammarane triterpene, betulatriterpene C 3-acetate (7), was isolated together with three known dammarane triterpenes, 24-epi-polacandrin 1,3-diacetate (8), betulatriterpene C (9) and 24-epi-polacandrin 3-acetate (10) from I. lutea, whereas 12 dammarane triterpenes, named probosciderols A-L (12-23), and the known compound betulafolienetriol (11) were isolated from P. louisiana. The structures of these compounds were elucidated by spectroscopic analysis including 2D-NMR techniques and chemical transformations. The 6-O-acetylglucosyloxy-fatty acids 1A-C (42%) and the dammarane triterpenes 7-10 (31%) were the two most abundant constituents in the

  2. Plant growth-promoting effects of native Pseudomonas strains on Mentha piperita (peppermint): an in vitro study.

    Science.gov (United States)

    Santoro, M V; Cappellari, L R; Giordano, W; Banchio, E

    2015-11-01

    Plant growth-promoting rhizobacteria (PGPR) affect growth of host plants through various direct and indirect mechanisms. Three native PGPR (Pseudomonas putida) strains isolated from rhizospheric soil of a Mentha piperita (peppermint) crop field near Córdoba, Argentina, were characterised and screened in vitro for plant growth-promoting characteristics, such as indole-3-acetic acid (IAA) production, phosphate solubilisation and siderophore production, effects of direct inoculation on plant growth parameters (shoot fresh weight, root dry weight, leaf number, node number) and accumulation and composition of essential oils. Each of the three native strains was capable of phosphate solubilisation and IAA production. Only strain SJ04 produced siderophores. Plants directly inoculated with the native PGPR strains showed increased shoot fresh weight, glandular trichome number, ramification number and root dry weight in comparison with controls. The inoculated plants had increased essential oil yield (without alteration of essential oil composition) and biosynthesis of major essential oil components. Native strains of P. putida and other PGPR have clear potential as bio-inoculants for improving productivity of aromatic crop plants. There have been no comparative studies on the role of inoculation with native strains on plant growth and secondary metabolite production (specially monoterpenes). Native bacterial isolates are generally preferable for inoculation of crop plants because they are already adapted to the environment and have a competitive advantage over non-native strains. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  3. Significance of diazotrophic plant growth-promoting Herbaspirillum sp. GW103 on phytoextraction of Pband Zn by Zea mays L.

    Science.gov (United States)

    Praburaman, Loganathan; Park, Sung-Hee; Cho, Min; Lee, Kui-Jae; Ko, Jeong-Ae; Han, Sang-Sub; Lee, Sang-Hyun; Kamala-Kannan, Seralathan; Oh, Byung-Taek

    2017-01-01

    Microbe-assisted phytoremediation has been considered a promising measure for the remediation of heavy metal-polluted soil. The aim of this study was to assess the effect of diazotrophic plant growth-promoting Herbaspirillum sp. GW103 on growth and lead (Pb) and zinc (Zn) accumulation in Zea mays L. The strain GW103 exhibited plant growth-promoting traits such as indole-3-acetic acid, siderophores, and 1-aminocyclopropane-1-carboxylic deaminase. Treatment of Z. mays L. plants with GW103 significantly increased 19, 31, and 52% of plant biomass and 10, 50, and 126% of chlorophyll a contents in Pb, Zn, and Pb + Zn-amended soils, respectively. Similarly, the strain GW103 significantly increased Pb and Zn accumulation in shoots and roots of Z. mays L., which were 77 and 25% in Pb-amended soil, 42 and 73% in Zn-amended soil, and 27 and 84% in Pb + Zn-amended soil. Furthermore, addition of GW103 increased 8, 12, and 7% of total protein content, catalase, and superoxide dismutase levels, respectively, in Z. mays L. plants. The results pointed out that isolate GW103 could potentially reduce the phytotoxicity of metals and increase Pb and Zn accumulation in Z. mays L. plant.

  4. Distribution and change patterns of free IAA, ABP 1 and PM H⁺-ATPase during ovary and ovule development of Nicotiana tabacum L.

    Science.gov (United States)

    Chen, Dan; Deng, Yingtian; Zhao, Jie

    2012-01-15

    Auxin plays key roles in flower induction, embryogenesis, seed formation and seedling development, but little is known about whether auxin regulates the development of ovaries and ovules before pollination. In the present report, we measured the content of free indole-3-acetic (IAA) in ovaries of Nicotiana tabacum L., and localized free IAA, auxin binding protein 1 (ABP1) and plasma membrane (PM) H⁺-ATPase in the ovaries and ovules. The level of free IAA in the developmental ovaries increased gradually from the stages of ovular primordium to the functional megaspore, but slightly decreased when the embryo sacs formed. Immunoenzyme labeling clearly showed that both IAA and ABP1 were distributed in the ovules, the edge of the placenta, vascular tissues and the ovary wall, while PM H⁺-ATPase was mainly localized in the ovules. By using immunogold labeling, the subcellular distributions of IAA, ABP1 and PM H⁺-ATPase in the ovules were also shown. The results suggest that IAA, ABP1 and PM H⁺-ATPase may play roles in the ovary and ovule initiation, formation and differentiation.

  5. Agrobacterium tumefaciens responses to plant-derived signaling molecules

    Directory of Open Access Journals (Sweden)

    Sujatha eSubramoni

    2014-07-01

    Full Text Available As a special phytopathogen, Agrobacterium tumefaciens infects a wide range of plant hosts and causes plant tumors also known as crown galls. The complexity of Agrobacterium-plant interaction has been studied for several decades. Agrobacterium pathogenicity is largely attributed to its evolved capabilities of precise recognition and response to plant-derived chemical signals. Agrobacterium perceives plant-derived signals to activate its virulence genes, which are responsible for transferring and integrating its T-DNA (Transferred DNA from its Tumour-inducing (Ti plasmid into the plant nucleus. The expression of T-DNA in plant hosts leads to the production of a large amount of indole-3-acetic acid (IAA, cytokinin (CK and opines. IAA and CK stimulate plant growth, resulting in tumor formation. Agrobacterium utilizes opines as nutrient sources as well as signals in order to activate its quorum sensing (QS to further promote virulence and opine metabolism. Intriguingly, Agrobacterium also recognizes plant-derived signals including -amino butyric acid (GABA and salicylic acid (SA to activate quorum quenching that reduces the level of QS signals, thereby avoiding the elicitation of plant defense and preserving energy. In addition, Agrobacterium hijacks plant-derived signals including SA, IAA, and ethylene (ET to down-regulate its virulence genes located on the Ti plasmid. Moreover, certain metabolites from corn (Zea mays also inhibit the expression of Agrobacterium virulence genes. Here we outline the responses of Agrobacterium to major plant-derived signals that impact Agrobacterium-plant interactions.

  6. Cholodny-Went revisited: a role for jasmonate in gravitropism of rice coleoptiles.

    Science.gov (United States)

    Gutjahr, Caroline; Riemann, Michael; Müller, Axel; Düchting, Petra; Weiler, Elmar W; Nick, Peter

    2005-11-01

    Gravitropism is explained by the Cholodny-Went hypothesis: the basipetal flow of auxin is diverted laterally. The resulting lateral auxin gradient triggers asymmetric growth. However, the Cholodny-Went hypothesis has been questioned repeatedly because the internal auxin gradient is too small to account for the observed growth asymmetry. Therefore, an additional gradient in indolyl-3-acetic acid (IAA) sensitivity has been suggested (Brauner and Hager in Planta 51:115-147, 1958). We challenged the Cholodny-Went hypothesis for gravitropism of rice coleoptiles (Oryza sativa L.) and found it to be essentially true. However, we observed, additionally, that the two halves of gravitropically stimulated coleoptiles responded differentially to the same amount of exogenous auxin: the auxin response is reduced in the upper flank but normal in the lower flank. This indicates that the auxin-gradient is amplified by a gradient of auxin responsiveness. Hormone contents were measured across the coleoptile by a GC-MS/MS technique and a gradient of jasmonate was detected opposing the auxin gradient. Furthermore, the total content of jasmonate increased during the gravitropic response. Jasmonate gradient and increase persist even when the lateral IAA gradient is inhibited by 1-N-naphtylphtalamic acid. Flooding with jasmonate delays the onset of gravitropic bending. Moreover, a jasmonate-deficient rice mutant bends more slowly and later than the wild type. We discuss a role of jasmonate as modulator of auxin responsiveness in gravitropism.

  7. lAA and BAP affect protein phosphorylation-dependent processes during sucrose-mediated G1 to S and G2 to M transitions in root meristem cells of Vicia faba

    Directory of Open Access Journals (Sweden)

    Justyna Teresa Polit

    2011-01-01

    Full Text Available In carbohydrate-starved root meristems of Vicia faba subsp. minor, the expression of two Principal Control Points located at the final stages of the G1 (PCP1 and G2 (PCP2 phases has been found to be correlated with a marked decrease of protein phosphorylation within cell nuclei, nucleoli and cytoplasm. Adopting the same experimental model in our present studies, monoclonal FITC conjugated antibodies that recognize phosphorylated form of threonine (αTPab-FITC were used to obtain an insight about how the indole-3-acetic acid (IAA, benzyl-6-aminopurine (BAP, and the mixture of both phytohormones influence the time-course changes in an overall protein phosphorylation during sucrose-mediated PCP1→S and PCP2→M transitions. Unsuspectedly, neither IAA, BAP, nor the mixture of both phytohormones supplied in combination with sucrose did up-regulate protein phosphorylation. However using the block-and-release method, it was shown that root meristems of Vicia provided with sucrose alone indicated higher levels of αTPab-FITC. Contrarily, phytohormones supplied in combination with sucrose induced apparent decline in phosphorylation of cell proteins, which - when compared with the influence of sucrose alone - became increasingly evident in time. Thus, it seems probable, that a general decline in the amount of αTPab-FITC labeled epitopes may overlay specific phosphorylations and dephosphorylations governed by the main cell cycle kinases and phosphatases.

  8. Root cap-dependent gravitropic U-turn of maize root requires light-induced auxin biosynthesis via the YUC pathway in the root apex

    Science.gov (United States)

    Suzuki, Hiromi; Yokawa, Ken; Nakano, Sayuri; Yoshida, Yuriko; Fabrissin, Isabelle; Okamoto, Takashi; Baluška, František; Koshiba, Tomokazu

    2016-01-01

    Gravitropism refers to the growth or movement of plants that is influenced by gravity. Roots exhibit positive gravitropism, and the root cap is thought to be the gravity-sensing site. In some plants, the root cap requires light irradiation for positive gravitropic responses. However, the mechanisms regulating this phenomenon are unknown. We herein report that maize roots exposed to white light continuously for ≥1–2h show increased indole-3-acetic acid (IAA) levels in the root tips, especially in the transition zone (1–3mm from the tip). Treatment with IAA biosynthesis inhibitors yucasin and l-kynurenine prevented any increases in IAA content and root curvature under light conditions. Analyses of the incorporation of a stable isotope label from tryptophan into IAA revealed that some of the IAA in roots was synthesized in the root apex. Furthermore, Zmvt2 and Zmyuc gene transcripts were detected in the root apex. One of the Zmyuc genes (ZM2G141383) was up-regulated by light irradiation in the 0–1mm tip region. Our findings suggest that IAA accumulation in the transition zone is due to light-induced activation of Zmyuc gene expression in the 0–1mm root apex region. Light-induced changes in IAA levels and distributions mediate the maize root gravitropic U-turn. PMID:27307546

  9. Evaluation of Long-Term Migration Testing from Can Coatings into Food Simulants: Polyester Coatings.

    Science.gov (United States)

    Paseiro-Cerrato, Rafael; Noonan, Gregory O; Begley, Timothy H

    2016-03-23

    FDA guidance for food contact substances recommends that for food packaging intended for use at sterilized, high temperature processed, or retorted conditions, a migration test with a retort step at 121 °C for 2 h followed by a 10 day migration test at 40 °C should be performed. These conditions are in intended to simulate processing and long-term storage. However, can coatings may be in contact with food for years, and there are very few data evaluating if this short-term testing accurately simulates migration over extended time periods. A long-term migration test at 40 °C with retorted and non-retorted polyester cans using several food simulants (water, 3% acetic acid, 10% ethanol, 50% ethanol, and isooctane) was conducted to verify whether traditional migration testing protocols accurately predict migration from food contact materials used for extended time periods. Time points were from 1 day to 515 days. HPLC-MS/MS was used to analyze polyester monomers, and oligomer migration was monitored using HPLC-DAD/CAD and HPLC-MS. Concentrations of monomers and oligomers increased during the migration experiments, especially in ethanol food simulants. The data suggest that current FDA migration protocols may need to be modified to address changes in migrants as a result of long-term storage conditions.

  10. Isolation of an endosulfan-degrading bacterium from a coffee farm soil: persistence and inhibitory effect on its biological functions.

    Science.gov (United States)

    Castillo, Jean Manuel; Casas, Jaime; Romero, Esperanza

    2011-12-15

    Endosulfan is a lypophilic persistent organic pollutant (POP) that has caused widespread concern due to its persistence in the environment, toxicity and bioaccumulation in living organisms. The aim of this study is to isolate endosulfan-degrading bacteria taken from five coffee farms historically exposed to this insecticide which could be used in future remediation strategies. The biodegradation capability of the isolated strain as well as endosulfan's impact on some of the strain's biological functions was studied. Endosulfan and its metabolites were analyzed using TLC and GC-MS. The isolated strain, capable of growing in a liquid culture treated with this insecticide as the sole sulfur source rather than a carbon source, was selected for further study. The isolated bacterium is Gram-negative, having the morphological and biochemical characteristics of Azotobacter sp. The remaining concentrations after 6 days, using 2 and 10 mg l(-1) of endosulfan, were 57.6 and 72.3% respectively, and the degradation constants were 0.12 d(-1) and 0.26 d(-1). Four metabolites were detected, one of which was identified as endosulfan ether. Endosulfan reduced nitrogenase activity but had no impact on indole 3-acetic acid production. Thus, these results suggest that this strain has the potential to act as a biocatalyst in endosulfan degradation. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Changes in endogenous hormone levels and redox status during enhanced adventitious rooting by rare earth element neodymium of Dendrobium densiflorum shoot cuttings

    Institute of Scientific and Technical Information of China (English)

    LUO Jianping; ZHANG Jingcheng; WANG Ying

    2008-01-01

    The effects of neodymium nitrate (Nd3+) on the adventitious rooting of Dendrobium densiflorum shoot cuttings were studied. The addition of Nd3+ (5 μmol/L) to culture medium significantly increased rooting frequency. Histological investigation showed that Nd3+ did not change the process of root initiation. Nd3+ did not influence total endogenous cytokinin levels, but significantly increased the level of en-dogenous indole-3-acetic acid (IAA) in the base of shoot cuttings. Compared to the control, the ratio of IAA/cytokinins was very high in the Nd3+ treatment. These results suggested that the enhanced rooting frequency may be related to the increase in endogenous IAA level in Nd3+ treatment. Analysis of enzyme activities showed that the enhanced accumulation of the endogenous IAA by Nd3+ should not be attributed to inhibition of IAA decomposition by IAA oxidase or promotion of cytokinin decomposition by cytokinin oxidase. Besides, Nd3+ increased the ratio of reduced glutathione (GSH) and oxidized glutathione (GSSG) in the process of adventitious rooting while the ratio of ascorbate (ASC) to dehydroascorbate (DHA) was not affected.

  12. Synthesis and pharmacological activity evaluation of arctigenin monoester derivatives.

    Science.gov (United States)

    Chen, Qiulian; Yang, Limin; Han, Mei; Cai, Enbo; Zhao, Yan

    2016-12-01

    Arctigenin (ARG), a nature medicine with many pharmacological activities, was poorly soluble in water and placed restriction on practical usage. Six novel arctigenin monoester derivatives were obtained from the reflux reaction with arctigenin, carboxylic acids (crotonic acid, furoic acid, 2-naphthalene acid and indol-3-acetic acid), EDCI and DMAP in dichloromethane at 60°C for 4-6h and their properties on nitrite scavenging assay were investigated in vitro. Based on the results, the one of the most effective derivatives, arctigenin β-indolylacetate (ARG6), was selected to study anti-tumor activity in vivo at doses of 20 and 40mg/kg. The results showed that comparison with ARG group, ARG6 exhibited more anti-tumor activity in H22 tumor-bearing mice. Furthermore, ARG6 exhibited less damage to the liver, kidney, spleen and thymus when compared with those in positive group. Biochemical parameters of ALT, AST, BUN and Cre showed ARG6 had little toxicity to mice as well. ARG6 significantly improved serum cytokine levels of IL-2, IL-6, IFN-γ and TNF-α, and decreased VEGF compared with ARG. Moreover, H & E staining, TUNEL assay and immunohistochemical of tumor issues also indicated that ARG6 exhibited anti-tumor activity in vivo. In brief, the present study provide a method to improve ARG anti-tumor activity and provide a reference for new anti-tumor agent.

  13. Physiological Basis of Photosynthetic Function and Senescence of Rice Leaves as Regulated by Controlled-Release Nitrogen Fertilizer

    Institute of Scientific and Technical Information of China (English)

    NIE Jun; ZHENG Sheng-xian; DAI Pin-gan; XIAO Jian; YI Guo-ying

    2005-01-01

    The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fertilizer (CRNF), urea and no nitrogen fertilizer. CRNF showed obvious effects on delaying the senescence and prolonging photosynthetic function duration of rice leaves. Compared with urea, CRNF could significantly increase the chlorophyll content of functional leaves in both early and late rice varieties, and this difference between the treatments became larger as rice growth progressed; CRNF increased the activities of active oxygen scavenging enzymes super oxide dismutase (SOD) and peroxidase (POD), and decreased the accumulation amount of malondialdehyde (MDA) in functional leaves during leaf aging; Photosynthetic rate of functional leaves in CRNF treatment was significantly higher than that in urea treatment. The result also indicated that CRNF could effectively regulate the contents of indole-3-acetic acid (IAA) and abscisic acid (ABA) in functional leaves; IAA content was higher and ABA content was lower in CRNF treatment than those in urea treatment. Therefore, application of CRNF could increase the rice yield significantly due to these physiological changes in the functional leaves.

  14. Development of a rapid LC-DAD/FLD method for the simultaneous determination of auxins and abscisic acid in plant extracts.

    Science.gov (United States)

    Bosco, Renato; Caser, Matteo; Vanara, Francesca; Scariot, Valentina

    2013-11-20

    Plant hormones play a crucial role in controlling plant growth and development. These groups of naturally occurring substances trigger physiological processes at very low concentrations, which mandate sensitive techniques for their quantitation. This paper describes a method to quantify endogenous (±)-2-cis-4-trans-abscisic acid, indole-3-acetic acid, indole-3-propionic acid, and indole-3-butyric acid. The method combines high-performance liquid chromatography (HPLC) with diode array and fluorescence detection in a single run. Hybrid tea rose 'Monferrato' matrices (leaves, petals, roots, seeds, androecium, gynoecium, and pollen) were used as references. Rose samples were separated and suspended in extracting methanol, after which (±)-2-cis-4-trans-abscisic acid and auxins were extracted by solvent extraction. Sample solutions were added first to cation solid phase extraction (SPE) cartridges and the eluates to anion SPE cartridges. The acidic hormones were bound to the last column and eluted with 5% phosphoric acid in methanol. Experimental results showed that this approach can be successfully applied to real samples and that sample preparation and total time for routine analysis can be greatly reduced.

  15. Determination of multiple phytohormones in fruits by high-performance liquid chromatography with fluorescence detection using dispersive liquid-liquid microextraction followed by precolumn fluorescent labeling.

    Science.gov (United States)

    Li, Guoliang; Lu, Shuaimin; Wu, Hongliang; Chen, Guang; Liu, Shucheng; Kong, Xiaojian; Kong, Weiheng; You, Jinmao

    2015-01-01

    Plant hormone determination in food matrices has attracted more and more attention because of their potential risks to human health. However, analytical methods for the analysis of multiple plant hormones remain poorly investigated. In the present study, a convenient, selective, and ultrasensitive high-performance liquid chromatography method for the simultaneous determination of multiple classes of plant hormones has been developed successfully using dispersive liquid-liquid microextraction followed by precolumn fluorescent labeling. Eight plant hormones in fruits including jasmonic acid, 12-oxo-phytodienoic acid, indole-3-acetic acid, 3-indolybutyric acid, 3-indolepropionic acid, gibberellin A3 , 1-naphthylacetic acid, and 2-naphthaleneacetic acid were analyzed by this method. The conditions employed for dispersive liquid-liquid microextraction were optimized systematically. The linearity for all plant hormones was found to be >0.9993 (R(2) values). This method offered low detection limits of 0.19-0.44 ng/mL (at a signal-to-noise ratio of 3), and method accuracies were in the range of 92.32-103.10%. The proposed method was applied to determine plant hormones in five kinds of food samples, and this method can achieve a short analysis time, low threshold levels of detection, and a high specificity for the analysis of targeted plant hormones present at trace level concentrations in complex matrices.

  16. Elongation growth of the leaf sheath base of Avena sativa seedlings: regulation by hormones and sucrose

    Science.gov (United States)

    Brock, T. G.; Kaufman, P. B.

    1991-01-01

    The leaf sheath base of the seedling of Avena sativa was characterized for growth response to hormones and sucrose. Six day old plants, raised under a 10:14 hr light:dark cycle, were excised at the coleoptilar node and 1 cm above the node for treatment. The growth of the leaf sheath base was promoted by gibberellic acid (GA3) and this response was dose dependent. The lag to response initiation was approximately 4 hr. Growth with or without GA3 (10 micromoles) was transient, diminishing appreciably after 48 hr. The addition of 10 mM sucrose greatly prolonged growth; the effect of GA3 and sucrose was additive. Neither indole-3-acetic acid (IAA) nor the cytokinin N6-benzyladenine (BA), alone or in combination, promoted the growth of leaf sheath bases. However, both significantly inhibited the action of GA3. The inhibitory effect of IAA was dose dependent and was not affected by the addition of BA or sucrose. These results indicate that the growth of leaf sheath bases of Avena sativa is promoted specifically by gibberellin, that this action depends on the availability of carbohydrates from outside of the leaf sheath base, and that the promotional effect of GA3 can be modified by either auxins or cytokinins.

  17. Changes in starch and inositol 1,4,5-trisphosphate levels and auxin transport are interrelated in graviresponding oat (Avena sativa) shoots.

    Science.gov (United States)

    Yun, Hye Sup; Joo, Se-Hwan; Kaufman, Peter B; Kim, Tae-Wuk; Kirakosyan, Ara; Philosoph-Hadas, Sonia; Kim, Seong-Ki; Chang, Soo Chul

    2006-11-01

    This study was conducted to unravel a mechanism for the gravitropic curvature response in oat (Avena sativa) shoot pulvini. For this purpose, we examined the downward movement of starch-filled chloroplast gravisensors, differential changes in inositol 1,4,5-trisphosphate (IP(3)) levels, transport of indole-3-acetic acid (IAA) and gravitropic curvature. Upon gravistimulation, the ratio for IAA levels in lower halves versus those in upper halves (L/U) increased from 1.0 at 0 h and reached a maximum value of 1.45 at 8 h. When shoots were grown in the dark for 10 d, to deplete starch in the chloroplast, the gravity-induced L/U of IAA was reduced to 1.0. N-naphthylphthalamic acid (NPA) and 2,3,5-triiodobenzoic acid (TIBA), both auxin transport inhibitors, significantly reduced the amount of gravitropic curvature and gravity-induced lateral IAA transport, but did not reduce the gravity-induced late change in the L/U ratio of IP(3) levels. U73122, a specific phospholipase C (PLC) inhibitor, decreased gravity-induced curvature. Because U73122 reduced the ratio of L/U of IAA imposed by gravistimulation, it is clear that IAA transport is correlated with changes in IP(3) levels upon gravistimulation. These results indicate that gravistimulation-induced differential lateral IAA transport may result from the onset of graviperception in the chloroplast gravisensors coupled with gravity-induced asymmetric changes in IP(3) levels in oat shoot pulvini.

  18. Growth regulator requirement for in vitro embryogenic cultures of snowdrop (Galanthus nivalis L.) suitable for germplasm preservation.

    Science.gov (United States)

    Resetár, Anna; Demeter, Zita; Ficsor, Emese; Balázs, Andrea; Mosolygó, Agnes; Szőke, Eva; Gonda, S; Papp, L; Surányi, G; Máthé, C

    2014-06-01

    In this study, we report on the production of bulb scale-derived tissue cultures capable of efficient shoot and plant regeneration in three genotypes of snowdrop (Galanthus nivalis L., Amaryllidaceae), a protected ornamental plant. For culture line A, high auxin and low cytokinin concentration is required for callus production and plant regeneration. The type of auxin is of key importance: α-naphthaleneacetic acid (NAA) in combination with indole-3-acetic acid (IAA) at concentrations of 2 mg L-1 or 2-10 mg L-1 NAA with 1 mg L-1 N6-benzyladenine (BA), a cytokinin on full-strength media are required for regeneration. Cultures showing regeneration were embryogenic. When lines B and C were induced and maintained with 2 mg L-1 NAA and 1 mg L-1 BA, they produced mature bulblets with shoots, without roots. Line A produced immature bulblets with shoots under the above culture condition. Amplified Fragment Length Polymorphism (AFLP) analysis showed that (i) genetic differences between line A and its bulb explants were not significant, therefore these tissue cultures are suitable for germplasm preservation, and (ii) different morphogenetic responses of lines A, B and C originated from genetic differences. Culture line A is suitable for field-growing, cultivation and germplasm preservation of G. nivalis and for the production of Amaryllidaceae alkaloids.

  19. 一株促生拮抗木霉菌的鉴定%Identification of an Antagonistic Trichoderma spp.Strain with Plant Growth-Promoting Activity

    Institute of Scientific and Technical Information of China (English)

    赵姣; 赵蕾

    2013-01-01

    A strain of Trichoderma spp. LT19 was isolated from soil in Shandong Province, which showed a broad inhibition spectrum against various soil - borne plant phytopathogenic fungi. It also exhibited some plant growth - promoting attributes such as phosphate solubilization, indol - 3 - acetic (IAA) productivity, 1 - aminocyclopropane - 1 -carboxylate (ACC) deaminase activity and siderophore (S) synthesis ability. The pot experiments showed that inoculation with the strain could increase the biomass of cucumber seedlings. Based on its morphology and ITS gene sequences, the strain LT19 was identified as Trichoderma asperellum.%从采集的植物根际土壤中分离到一株对黄瓜具有拮抗作用的木霉菌LT19,该菌能够促进黄瓜幼苗的生长,并具有溶磷、产嗜铁素、IAA及ACC脱氨酶的能力,显示了该菌在防治作物病害以及促进作物生长方面潜在的应用价值.根据形态特征与ITS序列分析,将其鉴定为棘孢木霉(Trichoderma asperellum).

  20. Potential for plant growth promotion of rhizobacteria associated with Salicornia growing in Tunisian hypersaline soils.

    Science.gov (United States)

    Mapelli, Francesca; Marasco, Ramona; Rolli, Eleonora; Barbato, Marta; Cherif, Hanene; Guesmi, Amel; Ouzari, Imen; Daffonchio, Daniele; Borin, Sara

    2013-01-01

    Soil salinity and drought are among the environmental stresses that most severely affect plant growth and production around the world. In this study the rhizospheres of Salicornia plants and bulk soils were collected from Sebkhet and Chott hypersaline ecosystems in Tunisia. Depiction of bacterial microbiome composition by Denaturing Gradient Gel Electrophoresis unveiled the occurrence of a high bacterial diversity associated with Salicornia root system. A large collection of 475 halophilic and halotolerant bacteria was established from Salicornia rhizosphere and the surrounding bulk soil, and the bacteria were characterized for the resistance to temperature, osmotic and saline stresses, and plant growth promotion (PGP) features. Twenty Halomonas strains showed resistance to a wide set of abiotic stresses and were able to perform different PGP activities in vitro at 5% NaCl, including ammonia and indole-3-acetic acid production, phosphate solubilisation, and potential nitrogen fixation. By using a gfp-labelled strain it was possible to demonstrate that Halomonas is capable of successfully colonising Salicornia roots in the laboratory conditions. Our results indicated that the culturable halophilic/halotolerant bacteria inhabiting salty and arid ecosystems have a potential to contribute to promoting plant growth under the harsh salinity and drought conditions. These halophilic/halotolerant strains could be exploited in biofertilizer formulates to sustain crop production in degraded and arid lands.

  1. Isolation and characterization of endophytic plant growth-promoting bacteria from date palm tree (Phoenix dactylifera L.) and their potential role in salinity tolerance.

    Science.gov (United States)

    Yaish, Mahmoud W; Antony, Irin; Glick, Bernard R

    2015-06-01

    Endophytic bacteria were isolated from date palm (Phoenix dactylifera L.) seedling roots, characterized and tested for their ability to help plants grow under saline conditions. Molecular characterization showed that the majority of these strains belonged to the genera Bacillus and Enterobacter and had different degrees of resistance to various antibiotics. Some of these strains were able to produce the enzyme 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and the plant growth regulatory hormone indole-3-acetic acid (IAA). Some strains were also able to chelate ferric iron (Fe(3+)) and solubilize potassium (K(+)), phosphorus (PO 4 (3-) ) and zinc (Zn(2+)), and produce ammonia. The results also showed that ACC deaminase activity and IAA production was slightly increased in some strains in response to an increase in NaCl concentration in the growth media. Consistent with these results, selected strains such as PD-R6 (Paenibacillus xylanexedens) and PD-P6 (Enterobacter cloacae) were able to enhance canola root elongation when grown under normal and saline conditions as demonstrated by a gnotobiotic root elongation assay. These results suggest that the isolated and characterized endophytic bacteria can alter ethylene and IAA levels and also facilitate nutrient uptake in roots and therefore have the potential role to promote the growth and development of date palm trees growing under salinity stress.

  2. Whole genome analysis of halotolerant and alkalotolerant plant growth-promoting rhizobacterium Klebsiella sp. D5A

    Science.gov (United States)

    Liu, Wuxing; Wang, Qingling; Hou, Jinyu; Tu, Chen; Luo, Yongming; Christie, Peter

    2016-05-01

    This research undertook the systematic analysis of the Klebsiella sp. D5A genome and identification of genes that contribute to plant growth-promoting (PGP) traits, especially genes related to salt tolerance and wide pH adaptability. The genome sequence of isolate D5A was obtained using an Illumina HiSeq 2000 sequencing system with average coverages of 174.7× and 200.1× using the paired-end and mate-pair sequencing, respectively. Predicted and annotated gene sequences were analyzed for similarity with the Kyoto Encyclopedia of Genes and Genomes (KEGG) enzyme database followed by assignment of each gene into the KEGG pathway charts. The results show that the Klebsiella sp. D5A genome has a total of 5,540,009 bp with 57.15% G + C content. PGP conferring genes such as indole-3-acetic acid (IAA) biosynthesis, phosphate solubilization, siderophore production, acetoin and 2,3-butanediol synthesis, and N2 fixation were determined. Moreover, genes putatively responsible for resistance to high salinity including glycine-betaine synthesis, trehalose synthesis and a number of osmoregulation receptors and transport systems were also observed in the D5A genome together with numerous genes that contribute to pH homeostasis. These genes reveal the genetic adaptation of D5A to versatile environmental conditions and the effectiveness of the isolate to serve as a plant growth stimulator.

  3. A novel Azotobacter vinellandii (SRIAz3) functions in salinity stress tolerance in rice.

    Science.gov (United States)

    Sahoo, Ranjan Kumar; Ansari, Mohammad Wahid; Pradhan, Madhusmita; Dangar, Tushar K; Mohanty, Santanu; Tuteja, Narendra

    2014-01-01

    The plant growth promoting rhizobacteria (PGPRs) as a biofertilizer provide agricultural benefits to advance various crops productivity. Recently, we discovered a novel Azotobacter vinellandii (SRIAz3) from rice rhizosphere, which is well competent to improve rice productivity. In this study, we investigated a role of A. vinellandii to confer salinity tolerance in rice (var. IR64). A. vinellandii inoculated rice plants showed higher proline and malondialdehyde content under 200 mM NaCl stress as compared with uninoculated one. The endogenous level of plant hormones viz., indole-3 acetic acid (IAA), gibberellins (GA3), zeatint (Zt) was higher in A. vinellandii inoculated plants under high salinity. The fresh biomass of root and shoot were relatively elevated in A. vinellandii inoculated rice. Further, the macronutrient profile was superior in A. vinellandii inoculated plants under salinity as compared with non-inoculated plants. The present findings further suggest that A. vinellandii, a potent biofertilzer, potentially confer salinity stress tolerance in rice via sustaining growth and improving compatible solutes and nutrients profile and thereby crop improvement.

  4. SINAT5 promotes ubiquitin-related degradation of NAC1 to attenuate auxin signals.

    Science.gov (United States)

    Xie, Qi; Guo, Hui-Shan; Dallman, Geza; Fang, Shengyun; Weissman, Allan M; Chua, Nam-Hai

    2002-09-12

    The plant hormone indole-3 acetic acid (IAA or auxin) controls many aspects of plant development, including the production of lateral roots. Ubiquitin-mediated proteolysis has a central role in this process. The genes AXR1 and TIR1 aid the assembly of an active SCF (Skp1/Cullin/F-box) complex that probably promotes degradation of the AUX/IAA transcriptional repressors in response to auxin. The transcription activator NAC1, a member of the NAM/CUC family of transcription factors, functions downstream of TIR1 to transduce the auxin signal for lateral root development. Here we show that SINAT5, an Arabidopsis homologue of the RING-finger Drosophila protein SINA, has ubiquitin protein ligase activity and can ubiquitinate NAC1. This activity is abolished by mutations in the RING motif of SINAT5. Overexpressing SINAT5 produces fewer lateral roots, whereas overexpression of a dominant-negative Cys49 --> Ser mutant of SINAT5 develops more lateral roots. These lateral root phenotypes correlate with the expression of NAC1 observed in vivo. Low expression of NAC1 in roots can be increased by treatment with a proteasome inhibitor, which indicates that SINAT5 targets NAC1 for ubiquitin-mediated proteolysis to downregulate auxin signals in plant cells.

  5. Thidiazuron: A potent cytokinin for efficient plant regeneration in Himalayan poplar (Populus ciliata Wall. using leaf explants

    Directory of Open Access Journals (Sweden)

    Gaurav Aggarwal

    2012-11-01

    Full Text Available Populus species are important resource for certain branches of industry and have special roles for scientific study on biological and agricultural systems. The present investigation was undertaken with an objective of enhancing the frequency of plant regeneration in Himalayan poplar (Populus ciliata Wall.. The effect of Thiadizuron (TDZ alone and in combination with adenine and α-Naphthalene acetic acid (NAA were studied on the regeneration potential of leaf explants. A high efficiency of shoot regeneration was observed in leaf (80.00% explants on MS basal medium supplemented with 0.024 mg/l TDZ and 79.7 mg/l adenine. Elongation and multiplication of shoots were obtained on Murashige and Skoog (MS basal medium, containing 0.5 mg/l 6. Benzyl aminopurine (BAP + 0.2mg/l Indole 3-acetic acid (IAA + 0.3 mg/l Gibberellic acid (GA3. High frequency root regeneration from in vitro developed shoots was observed on MS basal medium supplemented with 0.10 mg/l Indole 3-butyric acid(IBA. Maximum of the in vitro rooted plantlets were well accomplished to the mixture of sand: soil (1:1 and exhibited similar morphology with the field plants. A high efficiency plant regeneration protocol has been developedfrom leaf explants in Himalayan poplar (Populus ciliata Wall..

  6. Tissue culture and regeneration of an antimalarial plant, Artemisia sieberi Besser

    Directory of Open Access Journals (Sweden)

    A. Sharafi

    2014-10-01

    Full Text Available WHO recommends artemisinin-based combination therapies (ACTs as the most effective choice to treat malaria. For developing transgenic plants with high accumulation of artemisinin (by introducing genes encoding enzymes which regulate the biosynthetic pathway of artemisinin, an efficient protocol for tissue culture and plant regeneration is necessary. In the present study, leaf explants of Artemisia sieberi were cultivated in Murashige & Skoog based medium supplemented by combination of different plant growth regulators including 6-benzyl-aminopurine (BA, α-naphthalene-acetic acid (NAA, indole-3-acetic acid (IAA, picloram (Pic and 2,4-dichlorophenoxyacetic acid (2,4-D. The highest frequency of shoot induction was obtained on MS medium supplemented with 2 mg/L BA plus 0.05 mg/L NAA (95% regeneration and MS medium supplemented with 2 mg/L BA plus 0.5 mg/L IAA (85% regeneration. Rooting was obtained on MS medium supplemented with 0.05 mg/L NAA. The present study has revealed a simple, reliable, rapid and high efficient regeneration system for A. sieberi Besser as a source of artemisinin in short period via adventitious shoot induction procedure.

  7. In vitro regeneration of Centaurium erythraea Rafn from shoot tips and other seedling explants

    Directory of Open Access Journals (Sweden)

    Ewelina Piątczak

    2011-01-01

    Full Text Available Various explants from 30-day-old seedlings of Centaurium erythraea Rafn were evaluated for their morphogenetic capacity under in vitro culture conditions. Shoot formation from shoot tip explants was achieved mainly through adventitious bud differentiation. The highest number of shoots (up to 43.3 ± 2.2 from a single shoot tip was obtained on Murashige and Skoog medium (MS supplemented with indole-3-acetic acid (IAA (0.57 μM and 6-benzylaminopurine (BAP (4.4 μM. Adventitious shoot regeneration was also achieved through organogenesis from calluses obtained from hypocotyls, cotyledons, roots and leaves on MS medium containing IAA (2.85 μM and BAP (0.88 μM. Significant differences were noted between explant types in their effects on shoot regeneration. In the primary culture, the best response was obtained either from calluses derived from roots or leaves (44.4 ± 4.5 and 40.2 ± 6.0 shoots per callus, respectively. The number of subcultures of inoculated calluses affected both the multiplication rate (the number of shoots/explant and shoot morphology (the frequency of shoot hyperhydricity. Shoots rooted with the frequency of 94-100% after culture on MS medium without growth regulators. Plantlets were successfully acclimatized (97% under high relative humidity and then moved to the greenhouse.

  8. 辣椒胞质雄性不育系(CMS)子叶培养植株再生%In vitro Plant Regeneration of Pepper Cytoplasmic Male Sterility (CMS) Lines via Cotyledon Culture

    Institute of Scientific and Technical Information of China (English)

    邓明华; 文锦芬; 邹学校

    2009-01-01

    An in vitro shoot regeneration procedure was developed in pepper (Capsicum annuum L.) cytoplasmic male sterility (CMS) lines 9704A and 8214A using cotyledon as explant. The callus and bud cluster derived from cotyledon tissue explants were proliferated on Murashige and Skoog (MS) medium supplemented with different combinations of 6-benzladenine (6-BA), indole-3-acetic acid (IAA), gibberellic acid (GA3) and silver nitrate (AgNO3). From the formula of MS appended with 5.0 mg/L 6-BA, 1.0 mg/L IAA and 5.0 mg/L AgNO3, for the explants callus and bud cluster, the maximum differentiation rates (respectively 100.0% and 58.3%) and average number of adventitious bud from each explant (respectively 18.8 and 13.2) were obtained. The optimum medium combination for the elongation of adventitious bud was determined to be: MS+ 3.0 mg/L 6-BA + 1.0 mg/L IAA+ 5.0 mg/L AgNO3+ 2.0 mg/L GA3, from which the elongation rates of buds from callus and bud cluster were both 100%, and the average number of per explant adventitious bud number reached 6.3 and 5.8, respectively. And all the elongated shoots were successfully rooted on half-strength MS medium supplemented with 0.3-0.5 mg/L IAA.

  9. Copper mediates auxin signalling to control cell differentiation in the copper moss Scopelophila cataractae.

    Science.gov (United States)

    Nomura, Toshihisa; Itouga, Misao; Kojima, Mikiko; Kato, Yukari; Sakakibara, Hitoshi; Hasezawa, Seiichiro

    2015-03-01

    The copper (Cu) moss Scopelophila cataractae (Mitt.) Broth. is often found in Cu-enriched environments, but it cannot flourish under normal conditions in nature. Excess Cu is toxic to almost all plants, and therefore how this moss species thrives in regions with high Cu concentration remains unknown. In this study, we investigated the effect of Cu on gemma germination and protonemal development in S. cataractae. A high concentration of Cu (up to 800 µM) did not affect gemma germination. In the protonemal stage, a low concentration of Cu promoted protonemal gemma formation, which is the main strategy adopted by S. cataractae to expand its habitat to new locations. Cu-rich conditions promoted auxin accumulation and induced differentiation of chloronema into caulonema cells, whereas it repressed protonemal gemma formation. Under low-Cu conditions, auxin treatment mimicked the effects of high-Cu conditions. Furthermore, Cu-induced caulonema differentiation was severely inhibited in the presence of the auxin antagonist α-(phenylethyl-2-one)-indole-3-acetic acid, or the auxin biosynthesis inhibitor l-kynurenine. These results suggest that S. cataractae flourishes in Cu-rich environments via auxin-regulated cell differentiation. The copper moss might have acquired this mechanism during the evolutionary process to benefit from its advantageous Cu-tolerance ability. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  10. Characteristics of purple nonsulfur bacteria grown under Stevia residue extractions.

    Science.gov (United States)

    Xu, J; Feng, Y; Wang, Y; Lin, X

    2013-11-01

    As a consequence of the large-scale cultivation of Stevia plants, releases of plant residues, the byproduct after sweetener extraction, to the environment are inevitable. Stevia residue and its effluent after batching up contain large amounts of organic matters with small molecular weight, which therefore are a potential pollution source. Meanwhile, they are favourite substrates for micro-organism growths. This investigation was aimed to utilize the simulated effluent of Stevia residue to enrich the representative purple nonsulfur bacterium (PNSB), Rhodopseudomonas palustris (Rps. palustris), which has important economic values. The growth profile and quality of Rps. palustris were characterized by spectrophotometry, compared to those grown in common PNSB mineral synthetic medium. Our results revealed that the simulated effluent of Stevia residue not only stimulated Rps. palustris growth to a greater extent, but also increased its physiologically active cytochrome concentrations and excreted indole-3-acetic acid (IAA) content. This variation in phenotype of Rps. palustris could result from the shift in its genotype, further revealed by the repetitive sequence-based PCR (rep-PCR) fingerprinting analysis. Our results showed that the effluent of Stevia residue was a promising substrate for microbial growth.

  11. 2C-Methyl- D- erythritol 2,4-cyclodiphosphate synthase from Stevia rebaudiana Bertoni is a functional gene.

    Science.gov (United States)

    Kumar, Hitesh; Singh, Kashmir; Kumar, Sanjay

    2012-12-01

    Stevia [Stevia rebaudiana (Bertoni)] is a perennial herb which accumulates sweet diterpenoid steviol glycosides (SGs) in its leaf tissue. SGs are synthesized by 2C-methyl-D-erythritol 4-phosphate (MEP) pathway. Of the various enzymes of the MEP pathway, 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (MDS) (encoded by MDS) catalyzes the cyclization of 4-(cytidine 5' diphospho)-2C-methyl-D-erythritol 2-phosphate into 2C-methyl-D-erythritol 2,4-cyclodiphosphate. Complementation of the MDS knockout mutant strain of Escherichia coli, EB370 with putative MDS of stevia (SrMDS) rescued the lethal mutant, suggesting SrMDS to be a functional gene. Experiments conducted in plant growth chamber and in the field suggested SrMDS to be a light regulated gene. Indole 3-acetic acid (IAA; 50, 100 μM) down-regulated the expression of SrMDS at 4 h of the treatment, whereas, abscisic acid did not modulate its expression. A high expression of SrMDS was observed during the light hours of the day as compared to the dark hours. The present work established functionality of SrMDS and showed the role of light and IAA in regulating expression of SrMDS.

  12. Genotypic Characterization of Azotobacteria Isolated from Argentinean Soils and Plant-Growth-Promoting Traits of Selected Strains with Prospects for Biofertilizer Production

    Directory of Open Access Journals (Sweden)

    Esteban Julián Rubio

    2013-01-01

    Full Text Available The genetic diversity among 31 putative Azotobacter isolates obtained from agricultural and non-agricultural soils was assessed using rep-PCR genomic fingerprinting and identified to species level by ARDRA and partial 16S rRNA gene sequence analysis. High diversity was found among the isolates, identified as A. chroococcum, A. salinestris, and A. armeniacus. Selected isolates were characterized on the basis of phytohormone biosynthesis, nitrogenase activity, siderophore production, and phosphate solubilization. Indole-3 acetic-acid (IAA, gibberellin (GA3 and zeatin (Z biosynthesis, nitrogenase activity, and siderophore production were found in all evaluated strains, with variation among them, but no phosphate solubilization was detected. Phytohormones excreted to the culture medium ranged in the following concentrations: 2.2–18.2 μg IAA mL−1, 0.3–0.7 μg GA3 mL−1, and 0.5–1.2 μg Z mL−1. Seed inoculations with further selected Azotobacter strains and treatments with their cell-free cultures increased the number of seminal roots and root hairs in wheat seedlings. This latter effect was mimicked by treatments with IAA-pure solutions, but it was not related to bacterial root colonization. Our survey constitutes a first approach to the knowledge of Azotobacter species inhabiting Argentinean soils in three contrasting geographical regions. Moreover, this phenotypic characterization constitutes an important contribution to the selection of Azotobacter strains for biofertilizer formulations.

  13. Comparison of the bacterial community and characterization of plant growth-promoting rhizobacteria from different genotypes of Chrysopogon zizanioides (L.) Roberty (vetiver) rhizospheres.

    Science.gov (United States)

    Monteiro, Juliana Mendes; Vollú, Renata Estebanez; Coelho, Marcia Reed Rodrigues; Alviano, Celuta Sales; Blank, Arie Fitzgerald; Seldin, Lucy

    2009-08-01

    Molecular approaches [PCR-denaturing gradient gel electrophoresis (DGGE)] were used to determine whether three different vetiver (Chrysopogon zizanioides) genotypes, commercially used in Brazil and considered economically important over the world, select specific bacterial populations to coexist in their rhizospheres. DGGE profiles revealed that the predominant rhizospheric bacterial community hardly varies regarding the vetiver genotype. Moreover, using traditional cultivation methods, bacterial strains were isolated from the different rhizospheres. Colonies presenting different morphologies (83) were selected for determining their potential for plant growth promotion. More than half of the strains tested (57.8%) were amplified by PCR using nifH-based primers, specific for the enzyme nitrogenase reductase. The production of siderophores was observed in 88% of the strains, while the production of antimicrobial substances was detected in only 14.5% of the isolates when Micrococcus sp. was used as the indicator strain. Production of indole-3-acetic acid and the solubilization of phosphate were observed in 55.4% and 59% of the isolates, respectively. In total, 44 strains (53%) presented at least three characteristics of plant growth promotion and were submitted to amplified ribosomal DNA restriction analysis. Twenty-four genetic groups were formed at 100% similarity and one representative of each group was selected for their identification by partial 16S rRNA gene sequencing. They were affiliated with the genera Acinetobacter, Comamonas, Chryseobacterium, Klebsiella, Enterobacter, Pantoea, Dyella, Burkholderia, or Pseudomonas. These strains can be considered of great importance as possible biofertilizers in vetiver.

  14. Indole signalling and (micro)algal auxins decrease the virulence of Vibrio campbellii, a major pathogen of aquatic organisms.

    Science.gov (United States)

    Yang, Qian; Pande, Gde Sasmita Julyantoro; Wang, Zheng; Lin, Baochuan; Rubin, Robert A; Vora, Gary J; Defoirdt, Tom

    2017-05-01

    Vibrios belonging to the Harveyi clade are major pathogens of marine vertebrates and invertebrates, causing major losses in wild and cultured organisms. Despite their significant impact, the pathogenicity mechanisms of these bacteria are not yet completely understood. In this study, the impact of indole signalling on the virulence of Vibrio campbellii was investigated. Elevated indole levels significantly decreased motility, biofilm formation, exopolysaccharide production and virulence to crustacean hosts. Indole furthermore inhibited the three-channel quorum sensing system of V. campbellii, a regulatory mechanism that is required for full virulence of the pathogen. Further, indole signalling was found to interact with the stress sigma factor RpoS. Together with the observations that energy-consuming processes (motility and bioluminescence) are downregulated, and microarray-based transcriptomics demonstrating that indole decreases the expression of genes involved in energy and amino acid metabolism, the data suggest that indole is a starvation signal in V. campbellii. Finally, it was found that the auxins indole-3-acetic acid and indole-3-acetamide, which were produced by various (micro)algae sharing the aquatic environment with V. campbellii, have a similar effect as observed for indole. Auxins might, therefore, have a significant impact on the interactions between vibrios, (micro)algae and higher organisms, with major ecological and practical implications. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. Low-temperature conditioning induces chilling tolerance in 'Hayward' kiwifruit by enhancing antioxidant enzyme activity and regulating en-dogenous hormones levels.

    Science.gov (United States)

    Yang, Qingzhen; Zhang, Zhengke; Rao, Jingping; Wang, Yuping; Sun, Zhenying; Ma, Qiushi; Dong, Xiaoqing

    2013-12-01

    To understand the mechanisms leading to the enhanced chilling tolerance of kiwifruit by low-temperature conditioning (LTC, 12 °C for 3 days), this study investigated the effect of LTC on chilling tolerance and changes in antioxidant enzyme activities and endogenous hormones. LTC significantly alleviated chilling injury in kiwifruit. Fruits treated with LTC maintained lower respiration and ethylene production and higher firmness. Furthermore, this treatment inhibited the accumulation of malondialdehyde, superoxide radicals and hydrogen peroxide and the increase in membrane permeability and increased the activities of superoxide dismutase, catalase, ascorbate peroxidase and peroxidase under chilling stress. The treatment also maintained higher levels of endogenous abscisic acid (ABA), indole-3-acetic acid (IAA) and zeatin riboside (ZR), lower gibberellic acid (GA3) levels and higher ABA/GA3 and ABA/IAA ratios. The results suggested that LTC alleviated chilling injury in kiwifruit by improving antioxidant enzyme activities and maintaining higher levels of endogenous ABA, IAA and ZR, lower GA3 levels and higher ABA/GA3 and ABA/IAA ratios. © 2013 Society of Chemical Industry.

  16. Genome sequence and mutational analysis of plant-growth-promoting bacterium Agrobacterium tumefaciens CCNWGS0286 Isolated from a zinc-lead mine tailing.

    Science.gov (United States)

    Hao, Xiuli; Xie, Pin; Johnstone, Laurel; Miller, Susan J; Rensing, Christopher; Wei, Gehong

    2012-08-01

    The plant-growth-promoting bacterium Agrobacterium tumefaciens CCNWGS0286, isolated from the nodules of Robinia pseudoacacia growing in zinc-lead mine tailings, both displayed high metal resistance and enhanced the growth of Robinia plants in a metal-contaminated environment. Our goal was to determine whether bacterial metal resistance or the capacity to produce phytohormones had a larger impact on the growth of host plants under zinc stress. Eight zinc-sensitive mutants and one zinc-sensitive mutant with reduced indole-3-acetic acid (IAA) production were obtained by transposon mutagenesis. Analysis of the genome sequence and of transcription via reverse transcriptase PCR (RT-PCR) combined with transposon gene disruptions revealed that ZntA-4200 and the transcriptional regulator ZntR1 played important roles in the zinc homeostasis of A. tumefaciens CCNWGS0286. In addition, interruption of a putative oligoketide cyclase/lipid transport protein reduced IAA synthesis and also showed reduced zinc and cadmium resistance but had no influence on copper resistance. In greenhouse studies, R. pseudoacacia inoculated with A. tumefaciens CCNWGS0286 displayed a significant increase in biomass production over that without inoculation, even in a zinc-contaminated environment. Interestingly, the differences in plant biomass improvement among A. tumefaciens CCNWGS0286, A. tumefaciens C58, and zinc-sensitive mutants 12-2 (zntA::Tn5) and 15-6 (low IAA production) revealed that phytohormones, rather than genes encoding zinc resistance determinants, were the dominant factor in enhancing plant growth in contaminated soil.

  17. Application of the Organic Photosensitizers Bearing Two Carboxylic Acid Groups to Dye-Sensitized Solar Cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-Hua; YAO Yi-Shan; LI Chao; WANG Wei-Bo; CHENG Xue-Xin; WANG Xue-Song; ZHANG Bao-Wen

    2008-01-01

    Three electron donor-n bridge-electron acceptor(D-π-A)organic dyes bearing two carboxylic acid groups were applied to dye-sensitized solar cells(DSSC)as sensitizers,in Which one triphenylamine or modified triphenylamine and two rhodanine-3-acetic acid fragments act as D and A.respectively.It was found that the introduction of t-butyl or methoxy group in the triphenylamine subunit could lead to more efficient photoinduced intramolecular charge transfer,thus improving the overall photoelectric conversion efficiency of the resultant DSSC.Under global AM 1.5 solar irradiation(73 mW·cm-2),the dye molecule based on methoxy-substituted triphenylamine achieved the best photovoltaic performance:a short circuit photocurrent density(Jsc)of 12.63 mA·cm-2,an open circuit voltage(Voc)of 0.55 V,a fill factor(FF)of 0.62,corresponding to an overall efficiency(η)of 5.9%.

  18. Insect stings to change gear for healthy plant: Improving maize drought tolerance by whitefly infestation.

    Science.gov (United States)

    Park, Yong-Soon; Ryu, Choong-Min

    2016-05-03

    Since plants first appeared about 1.1 billion years ago, they have been faced with biotic and abiotic stresses in their environment. To overcome these stresses, plants developed defense strategies. Accumulating evidence suggests that the whitefly [Bemisia tabaci (Genn.)] affects the regulation of plant defenses and physiology. A recent study demonstrates that aboveground whitefly infestation positively modulates root biomass and anthocyanin pigmentation on brace roots of maize plants (Zea mays L.). In agreement with these observations, indole-3-acetic acid (IAA) and jasmonic acid (JA) contents and the expression of IAA- and JA-related genes are higher in whitefly-infested maize plants than in non-infected control plants. Interestingly, the fresh weight of whitefly-infested maize plants is approximately 20% higher than in non-infected control plants under water stress conditions. Further investigation has revealed that hydrogen peroxide (H2O2) accumulates in whitefly-infested maize plants after water stoppage. Taken together, these results suggest that activation of phytohormones- (i.e., IAA and JA) and H2O2-mediated maize signaling pathways triggered by aboveground whitefly infestation promotes drought resistance. They also provide an insight into how inter-kingdom interactions can improve drought tolerance in plants.

  19. Improved dialytic removal of protein-bound uraemic toxins with use of albumin binding competitors: an in vitro human whole blood study.

    Science.gov (United States)

    Tao, Xia; Thijssen, Stephan; Kotanko, Peter; Ho, Chih-Hu; Henrie, Michael; Stroup, Eric; Handelman, Garry

    2016-03-22

    Protein-bound uraemic toxins (PBUTs) cause various deleterious effects in end-stage kidney disease patients, because their removal by conventional haemodialysis (HD) is severely limited by their low free fraction in plasma. Here we provide an experimental validation of the concept that the HD dialytic removal of PBUTs can be significantly increased by extracorporeal infusion of PBUT binding competitors. The binding properties of indoxyl sulfate (IS), indole-3-acetic acid (IAA) and hippuric acid (HIPA) and their binding competitors, ibuprofen (IBU), furosemide (FUR) and tryptophan (TRP) were studied in uraemic plasma. The effect of binding competitor infusion on fractional removal of PBUT was then quantified in an ex vivo single-pass HD model using uraemic human whole blood. The infusion of a combination of IBU and FUR increased the fractional removal of IS from 6.4 ± 0.1 to 18.3 ± 0.4%. IAA removal rose from 16.8 ± 0.3 to 34.5 ± 0.7%. TRP infusion increased the removal of IS and IAA to 10.5 ± 0.1% and 27.1 ± 0.3%, respectively. Moderate effects were observed on HIPA removal. Pre-dialyzer infusion of PBUT binding competitors into the blood stream can increase the HD removal of PBUTs. This approach can potentially be applied in current HD settings.

  20. CsAGP1, a gibberellin-responsive gene from cucumber hypocotyls, encodes a classical arabinogalactan protein and is involved in stem elongation.

    Science.gov (United States)

    Park, Me Hea; Suzuki, Yoshihito; Chono, Makiko; Knox, J Paul; Yamaguchi, Isomaro

    2003-03-01

    Fluorescence differential display was used to isolate the gibberellin (GA)-responsive gene, CsAGP1, from cucumber (Cucumis sativus) hypocotyls. A sequence analysis of CsAGP1 indicated that the gene putatively encodes a "classical" arabinogalactan protein (AGP) in cucumber. Transgenic tobacco (Nicotiana tabacum) plants overexpressing CsAGP1 under the control of the cauliflower mosaic virus 35S promoter produced a Y(betaGlc)(3)-reactive proteoglycan in addition to AGPs present in wild-type tobacco plants. Immuno-dot blotting of the product, using anti-AGP antibodies, showed that the CsAGP1 protein had the AGP epitopes common to AGP families. The transcription level of CsAGP1 in cucumber hypocotyls increased in response not only to GA but also to indole-3-acetic acid. Although CsAGP1 is expressed in most vegetative tissues of cucumber, including the shoot apices and roots, the GA treatment resulted in an increase in the mRNA level of CsAGP1 only in the upper part of the hypocotyls. Y(betaGlc)(3), which selectively binds AGPs, inhibited the hormone-promoted elongation of cucumber seedling hypocotyls. Transgenic plants ectopically expressing CsAGP1 showed a taller stature and earlier flowering than the wild-type plants. These observations suggest that CsAGP1 is involved in stem elongation.

  1. Auxin and Cytokinin Metabolism and Root Morphological Modifications in Arabidopsis thaliana Seedlings Infected with Cucumber mosaic virus (CMV or Exposed to Cadmium

    Directory of Open Access Journals (Sweden)

    Adriano Sofo

    2013-03-01

    Full Text Available Arabidopsis thaliana L. is a model plant but little information is available about morphological root changes as part of a phytohormonal common response against both biotic and abiotic stressors. For this purpose, two-week-old Arabidopsis seedlings were treated with 10 µM CdSO4 or infected with CMV. After 12 days the entire aerial parts and the root system were analyzed, and the presence of CMV or the accumulation of Cd were detected. Microscopic analysis revealed that both CMV and Cd influenced root morphology by a marked development in the length of root hairs and an intense root branching if compared to controls. Among the three treatments, Cd-treated seedlings showed a shorter root axis length and doubled their lateral root diameter, while the lateral roots of CMV-infected seedlings were the longest. The root growth patterns were accompanied by significant changes in the levels of indole-3-acetic acid, trans-zeatin riboside, dihydrozeatin riboside, as a probable consequence of the regulation of some genes involved in their biosynthesis/degradation. The opposite role on root development played by the phythormones studied is discussed in detail. The results obtained could provide insights into novel strategies for plant defense against pathogens and plant protection against pollutants.

  2. Genome-wide analysis of auxin response factor gene family members in medicinal model plant Salvia miltiorrhiza

    Directory of Open Access Journals (Sweden)

    Zhichao Xu

    2016-06-01

    Full Text Available Auxin response factors (ARFs can function as transcriptional activators or repressors to regulate the expression of auxin response genes by specifically binding to auxin response elements (AuxREs during plant development. Based on a genome-wide strategy using the medicinal model plant Salvia miltiorrhiza, 25 S. miltiorrhiza ARF (SmARF gene family members in four classes (class Ia, IIa, IIb and III were comprehensively analyzed to identify characteristics including gene structures, conserved domains, phylogenetic relationships and expression patterns. In a hybrid analysis of the phylogenetic tree, microRNA targets, and expression patterns of SmARFs in different organs, root tissues, and methyl jasmonate or indole-3-acetic acid treatment conditions, we screened for candidate SmARFs involved in various developmental processes of S. miltiorrhiza. Based on this analysis, we predicted that SmARF25, SmARF7, SmARF16 and SmARF20 are involved in flower, leaf, stem and root development, respectively. With the further insight into the targets of miR160 and miR167, specific SmARF genes in S. miltiorrhiza might encode products that participate in biological processes as described for ARF genes in Arabidopsis. Our results provide a foundation for understanding the molecular basis and regulatory mechanisms of SmARFs in S. miltiorrhiza.

  3. Characterization of plant-growth-promoting effects and concurrent promotion of heavy metal accumulation in the tissues of the plants grown in the polluted soil by Burkholderia strain LD-11.

    Science.gov (United States)

    Huang, Gui-Hai; Tian, Hui-Hui; Liu, Hai-Ying; Fan, Xian-Wei; Liang, Yu; Li, You-Zhi

    2013-01-01

    Plant-growth-promoting (PGP) bacteria especially with the resistance to multiple heavy metals are helpful to phytoremediation. Further development of PGP bacteria is very necessary because of the extreme diversity of plants, soils, and heavy metal pollution. A Burkholderia sp. strain, numbered LD-11, was isolated, which showed resistances to multiple heavy metals and antibiotics. It can produce indole-3-acetic acid, 1-aminocyclopropane-1-carboxylic acid deaminase and siderophores. Inoculation with the LD-11 improved germination of seeds of the investigated vegetable plants in the presence of Cu, promoted elongation of roots and hypocotyledonary axes, enhanced the dry weights of the plants grown in the soils polluted with Cu and/or Pb, and increased activity of the soil urease and the rhizobacteria diversity. Inoculation with the LD-11 significantly enhanced Cu and/or Pb accumulation especially in the roots of the plants grown in the polluted soils. Notably, LD-11 could produce siderophores in the presence of Cu. Conclusively, the PGP effects and concurrent heavy metal accumulation in the plant tissues results from combined effects of the above-mentioned multiple factors. Cu is an important element that represses production of the siderophore by the bacteria. Phytoremediation by synergistic use of the investigated plants and the bacterial strain LD-11 is a phytoextraction process.

  4. Isolation of Pantoea ananatis from sugarcane and characterization of its potential for plant growth promotion.

    Science.gov (United States)

    da Silva, J F; Barbosa, R R; de Souza, A N; da Motta, O V; Teixeira, G N; Carvalho, V S; de Souza, A L S R; de Souza Filho, G A

    2015-11-30

    Each year, approximately 170 million metric tons of chemical fertilizer are consumed by global agriculture. Furthermore, some chemical fertilizers contain toxic by-products and their long-term use may contaminate groundwater, lakes, and rivers. The use of plant growth-promoting bacteria may be a cost-effective strategy for partially replacing conventional chemical fertilizers, and may become an integrated plant nutrient solution for sustainable crop production. The main direct bacteria-activated mechanisms of plant growth promotion are based on improvement of nutrient acquisition, siderophore biosynthesis, nitrogen fixation, and hormonal stimulation. The aim of this study was to isolate and identify bacteria with growth-promoting activities from sugarcane. We extracted the bacterial isolate SCB4789F-1 from sugarcane leaves and characterized it with regard to its profile of growth-promoting activities, including its ability to colonize Arabidopsis thaliana. Based on its biochemical characteristics and 16S rDNA sequence analysis, this isolate was identified as Pantoea ananatis. The bacteria were efficient at phosphate and zinc solubilization, and production of siderophores and indole-3-acetic acid in vitro. The isolate was characterized by Gram staining, resistance to antibiotics, and use of carbon sources. This is the first report on zinc solubilization in vitro by this bacterium, and on plant growth promotion following its inoculation into A. thaliana. The beneficial effects to plants of this bacterium justify future analysis of inoculation of economically relevant crops.

  5. An auxin-binding protein is localized to the plasma membrane of maize coleoptile cells: Identification by photoaffinity labeling and purification of a 23-kDa polypeptide

    Energy Technology Data Exchange (ETDEWEB)

    Feldwisch, J.; Zettl, R.; Hesse, F.; Schell, J.; Palme, K. (Max-Planck-Inst. fuer Zuechtungsforschung, Koeln (West Germany))

    1992-01-15

    Plasma membrane vesicles were isolated from maize (Zea mays L.) coleoptile tissue by aqueous two-phase partitioning and assayed for homogeneity by the use of membrane-specific enzymatic assays. Using 5-azido-(7-{sup 3}H)indole-3-acetic acid (({sup 3}H)N{sub 3}IAA), the authors identified several IAA-binding proteins with the molecular masses of 60 kDa (pm60), 58 kDa (pm58), and 23 kDa (pm23). Using Triton X-114, they were able to selectively extract pm23 from the plasma membrane. They show that auxins and functional analogues compete with ({sup 3}H)N{sub 3}IAA for binding to pm23. They found that PAB130, a polyclonal antibody raised against auxin-binding protein 1 (ABP-1), recognized ABP-1 as well as pm23. This suggests that pm23 shares common epitopes with ABP-1. In addition, they identified an auxin-binding protein with a molecular mass of 24 kDa (pm24), which was detected in microsomal but not in plasma membrane vesicle preparations. Like pm23 this protein was extracted from membrane vesicles with Triton X-114. They designed a purification scheme allowing simultaneous purification of pm23 and pm24. Homogeneous pm23 and pm24 were obtained from coleoptile extracts after 7,000-fold purification.

  6. Plant growth regulators induced urease activity in Cucurbita pepo L. cotyledons.

    Science.gov (United States)

    El Shora, Hamed M; Ali, Awatif S

    2016-03-01

    This study is aimed to investigate the activity of urease (EC 3.5.1.5, urea amidohydrolase) that catalyzes the hydrolysis of urea in 5-day-old Cucurbita pepo cotyledons subjected to various concentrations of different growth regulators. The treatment of C. pepo cotyledons with different concentrations (100-600 μmol) of different auxins [indole-3-acetic acid (IAA), indole butyric acid (IBA), indole propionic acid (IPA) and naphthalene acetic acid (NAA)]; or with different concentrations (100-300 μmol) of different cytokinins [kinetin, zeatin and benzyladenine (6-BA)] resulted in a significant increase of urease activity, compared to control. The optimal effects were recorded for each of 500 μmol of IAA and 300 μmol of zeatin treatments. A gradual increase in urease activity was detected in cotyledons treated with various concentrations (0.2-1.0 mM) of 28-homobrassinolide (HBL), in relative to control. A substantial increase in urease activity was observed in cotyledons subjected to different concentrations of triazole (10-60 mg L(-1)), containing either triadimefon (TDM) or hexaconazole (HEX), compared to control. The combination of 300 μmol zeatin with any of protein inhibitors, namely 5-fluorouridine (FUrd), cordycepin and α-amanitin, resulted in the alleviation of their inhibitory effect on the urease activity.

  7. Multiresidue analysis of plant growth regulators in grapes by triple quadrupole and quadrupole-time of flight-based liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Oulkar, Dasharath P; Banerjee, Kaushik; Kulkarni, Sunil

    2011-01-01

    A selective and sensitive LC-MS/MS method is presented for simultaneous determination of 12 plant growth regulators, viz., indol-3-acetic acid, indol-3-butyric acid, kinetin, zeatin, 6-benzyl aminopurine, gibberellic acid, abscisic acid, chlormequat chloride, forchlorfenuron, paclobutrazole, daminozide, and 2,4-dichlorophenoxy acetic acid, in bud sprouts and grape berries. The sample preparation method involved extraction of homogenized sample (5 g) with 40 mL methanol (80%), and final determination was by LC-MS/MS in the multiple reaction monitoring (MRM) mode with time segmentation for quantification supported by complementary analysis by quadrupole-time of flight (Q-TOF) MS with targeted high-resolution MS/MS scanning for confirmatory identification based on accurate mass measurements. The recovery of the test compounds ranged within 90-107% with precision RSD less than 5% (n = 6). The method could be successfully applied in analyzing incurred residue samples, and the strength of accurate mass analysis could be utilized in identifying the compounds in cases where the qualifier MRM ions were absent or at an S/N less than 3:1 due to low concentrations.

  8. The Effect Of Some Plant Growth Regulators And Their Combination With Methyl Jasmonate On Anthocyanin Formation In Roots Of Kalanchoe Blossfeldiana

    Directory of Open Access Journals (Sweden)

    Góraj Justyna

    2014-12-01

    Full Text Available In this study, we investigated the effect of plant growth regulators (PGRs - auxins, gibberellin, cytokinin, abscisic acid, brassinosteroid, ethylene and their interaction with methyl jasmonate (JA-Me applied to roots of the whole plants Kalanchoe blossfeldiana on the accumulation of anthocyanins in roots. The highest stimulation of anthocyanins synthesis was stated with application of JA-Me alone. In response to treatments with the other tested PGRs, the content of anthocyanins in roots of a whole plant was different depending on the concentration of the PGR when being applied alone or together with JA-Me. Auxin, indole-3-acetic acid (IAA at a concentration of 50 mg·L-1, indole-3-butyric acid (IBA at 5 mg·L-1 and abscisic acid (ABA at 10 mg·L-1 induced anthocyanin accumulation with approximately 60-115% compared to the control while 24-epibrassinolid (epiBL, gibberellic acid (GA3 and 6-benzylaminopurine (BAP had no effect on the anthocyanin accumulation. The simultaneous administration of the PGRs with JA-Me usually resulted in the accumulation of anthocyanins in roots in a manner similar to that caused by JA-Me. PGRs applied to isolated roots did not stimulate anthocyanin accumulation, except for the combination of JA-Me with 50 mg·L-1 IAA.

  9. The improved phytoextraction of lead (Pb) and the growth of maize (Zeamays L.): the role of plant growth regulators (GA3 and IAA) and EDTA alone and in combinations.

    Science.gov (United States)

    Hadi, Fazal; Bano, Asghari; Fuller, Michael P

    2010-06-01

    This investigation was made to examine the role of gibberellic acid (GA(3)), indole-3-acetic acid (IAA) and EDTA in improving phytoextraction of the Pb and plant growth on Pb added soil. GA(3), IAA and EDTA were applied separately and in combinations. GA(3) and IAA were applied as foliar spray and seed soaking. EDTA was applied in single and split doses. Analysis of the Pb in different parts of plant was carried out using atomic absorption/flame spectrophotometer. EDTA significantly reduced the plant growth and dry biomass, whereas GA(3) and IAA foliar spray increased it significantly when compared with control (only Pb added soil). In combined treatments of EDTA+GA(3) and EDTA+IAA, the growth and biomass was restored, which shows that GA(3) and IAA did compensate the negative effect of EDTA on plant growth. The separate treatments of EDTA, GA(3) and IAA increased the Pb uptake and translocation significantly moreover in combine treatments, synergistic effect was found and remarkable increase in Pb uptake and translocation into shoot was observed. EDTA increased the Pb uptake but declined the biomass; subsequently the total Pb accumulation was decreased in plant. The maximum total Pb was found in combined treatment of EDTA+GA(3). These findings suggest more investigation to find a combination of GA(3) with a very low concentration of EDTA, as in high concentration it causes soil and ground water pollution.

  10. Influence of Plant Growth Regulators on In Vitro Shoot Multiplication and Plantlet Formation in Cassia angustifolia Vahl

    Directory of Open Access Journals (Sweden)

    Iram Siddique

    2015-10-01

    Full Text Available ABSTRACTAn effective and improved plant regeneration system was successfully developed using shoot tip explants taken from a two years old mature plant of Cassia angustifolia. The effect of different cytokinins, [6-benzyladenine (BA, Kinetin (Kin and thidiazuron (TDZ] at different concentrations (0.5-10 µM were evaluated as augmented with Murashige and Skoog (MS 1962 medium. Among all the cytokinins tested, TDZ (5.0 µM was optimum in inducing multiple shoots as compared to BA and Kin. The rate of shoot multiplication was increased when optimal concentration (5.0 µM of BA and Kin was tested with different concentration (0.1-1.0 µM of Indole-3- acetic acid (IAA. Among all the combinations tested, the maximum rate of shoot multiplication was obtained on MS medium supplemented with 5.0 µM BA and 0.5 µM IAA. The number of the shoots and shoot length developed in TDZ was increased when transferred to MS medium devoid of TDZ. After every subculture, rate of the shoot multiplication and shoot length showed increment and continued even after fifth subculture without any decline rate. In vitro rooting in regenerated shoots were best obtained in half-strength MS medium supplemented with 2.0 µM indole-3- butyric acid (IBA. Plantlets with well-developed shoot and roots were successfully hardened off in earthen pots containing garden soil and grown in greenhouse with 80% survival rate.

  11. Gadolinium-loaded gel scintillators for neutron and antineutrino detection

    Science.gov (United States)

    Riddle, Catherine Lynn; Akers, Douglas William; Demmer, Ricky Lynn; Paviet, Patricia Denise; Drigert, Mark William

    2016-11-29

    A gadolinium (Gd) loaded scintillation gel (Gd-ScintGel) compound allows for neutron and gamma-ray detection. The unique gel scintillator encompasses some of the best features of both liquid and solid scintillators, yet without many of the disadvantages associated therewith. Preferably, the gel scintillator is a water soluble Gd-DTPA compound and water soluble fluorophores such as: CdSe/ZnS (or ZnS) quantum dot (Q-dot) nanoparticles, coumarin derivatives 7-hydroxy-4-methylcoumarin, 7-hydroxy-4-methylcoumarin-3-acetic acid, 7-hydroxycoumarin-3-carboxylic acid, and Alexa Fluor 350 as well as a carbostyril compound, carbostyril 124 in a stable water-based gel, such as methylcellulose or polyacrylamide polymers. The Gd-loaded ScintGel allows for a homogenious distribution of the Gd-DTPA and the fluorophores, and yields clean fluorescent emission peaks. A moderator, such as deuterium or a water-based clear polymer, can be incorporated in the Gd-ScintGel. The gel scintillators can be used in compact detectors, including neutron and antineutrino detectors.

  12. The Effect of Plant Growth Regulators on Callus Induction and Regeneration of Amygdalus communis

    Directory of Open Access Journals (Sweden)

    Naimeh SHARIFMOGHADAM

    2011-08-01

    Full Text Available The Almond (Amygdalus communis is one of the most important and oldest commercial nut crops, belonging to the Rosaceae family. Almond has been used as base material in pharmaceutical, cosmetic, hygienically and food industry. Propagation by tissue culture technique is the most important one in woody plants. In the current research, in vitro optimization of tissue culture and mass production of almond was investigated. In this idea, explants of actively growing shoots were collected and sterilized, then transferred to MS medium with different concentrations and combinations of plant growth regulators. The experiment was done in completely randomized blocks design, with 7 treatment and 30 replications. After 4 weeks, calli induction, proliferation, shoot length and number of shoot per explants were measured. Results showed that the best medium for shoot initiation and proliferation was MS + 0.5 mg/l IAA (Indol-3-Acetic Acid + 1 mg/l BA (Benzyl Adenine. Autumn was the best season for collecting explants. The shoots were transferred to root induction medium with different concentrations of plant growth regulators. The best root induction medium was MS + 0.5 mg/l IBA (Indol Butyric Acid.

  13. INVESTIGATION OF A MIXTURE CONTAINING ALPRAZOLAM, CODEINE AND PARACETAMOL USING THIN-LAYER AND HIGH PERFORMANCE LIQUID CHROMATOGRAPHY METHODS.

    Science.gov (United States)

    Ciegis, Paulius; Zevzikovas, Andrejus; Zevzikoviene, Augusta; Nenortiene, Palma; Kazlauskiene, Daiva

    2016-01-01

    The increasing drug consumption in Lithuania and all over the world makes us think about the negative consequences - the risk of toxicity. Fast and accurate identification of material that caused the poisoning reduces the probability in death cases and makes easier to determine the main cause of death. The results have shown that the most appropriate systems of solvents for qualitative analysis by TLC method of the mixture consisting of alprazolam, codeine and paracetanol are: system "D" (trichloromethane : acetone : conc. ammonia = 55 : 40 : 5 (v/v/v)) and system "F" (trichloromethane : diethyl ether: isobutanol : conc. ammonia = 50 : 30 : 15 : 5 (v/v/v/v)). For qualitative analysis of the mixture consisting of alprazolam, codeine and paracetamol by HPLC method the chromatographic column ACE C18 (25 cm x 4.6 mm x 5 µm), gradient elution mode (mixture of 3% acetic acid and methanol and the flow rate 1 mL/min have been used. The injection volume was 10 pL. Photodiode array detector (210 - 240 nm range) has been used. UV absorption spectra of materials measured using photodiode array detector have been identical to those presented in the scientific literature.

  14. Auxin Is Rapidly Induced by Herbivore Attack and Regulates a Subset of Systemic, Jasmonate-Dependent Defenses1[OPEN

    Science.gov (United States)

    Machado, Ricardo A. R.; Robert, Christelle A. M.; Arce, Carla C. M.; Ferrieri, Abigail P.; Jimenez-Aleman, Guillermo H.

    2016-01-01

    Plant responses to herbivore attack are regulated by phytohormonal networks. To date, the role of the auxin indole-3-acetic acid (IAA) in this context is not well understood. We quantified and manipulated the spatiotemporal patterns of IAA accumulation in herbivore-attacked Nicotiana attenuata plants to unravel its role in the regulation of plant secondary metabolism. We found that IAA is strongly, rapidly, and specifically induced by herbivore attack. IAA is elicited by herbivore oral secretions and fatty acid conjugate elicitors and is accompanied by a rapid transcriptional increase of auxin biosynthetic YUCCA-like genes. IAA accumulation starts 30 to 60 s after local induction and peaks within 5 min after induction, thereby preceding the jasmonate (JA) burst. IAA accumulation does not require JA signaling and spreads rapidly from the wound site to systemic tissues. Complementation and transport inhibition experiments reveal that IAA is required for the herbivore-specific, JA-dependent accumulation of anthocyanins and phenolamides in the stems. In contrast, IAA does not affect the accumulation of nicotine or 7-hydroxygeranyllinalool diterpene glycosides in the same tissue. Taken together, our results uncover IAA as a rapid and specific signal that regulates a subset of systemic, JA-dependent secondary metabolites in herbivore-attacked plants. PMID:27485882

  15. [Determination of 46 plasticizers in food contact polyvinyl chloride packaging materials and their migration into food simulants by gas chromatography-mass spectrometry].

    Science.gov (United States)

    Guo, Chunhai; Bo, Haibo; Duan, Wenzhong; Jia, Haitao; Chen, Ruichun; Ma, Yusong; Ai, Lianfeng

    2011-01-01

    A gas chromatography-mass spectrometry (GC-MS) method was developed for the determination of 46 plasticizers in food contact polyvinyl chloride (PVC) packaging materials and their migration into food simulants, i. e. water, 3% acetic acid, 10% ethanol and olive oil. Plasticizers in the PVC packaging materials, aqueous food simulants and olive oil food simulants were extracted by the dissolution-precipitation, liquid-liquid extraction and gel permeation chromatography (GPC) approaches, respectively. The extracts were analyzed by GC-MS in selective ion monitoring (SIM) mode and quantified using the external standard method. The cal-ibration curves were linear in the ranges of 0.1-2.0 mg/L with the correlation coefficients of 0.9910-0. 999 9. The limits of detection were from 0. 005 mg/kg to 0. 05 mg/kg ( S/N = 5 ). The recoveries at 3 spiked levels were 69.51%-107. 21% and the relative standard deviations (RSDs n = 6) ranged from 3.53% to 18.95%. These results show that this method is fast, sensitive and accurate for the qualitative and quantitative determination of plasticizers in food contact plastic products and 4 types of food simulants.

  16. YUCCA-mediated auxin biogenesis is required for cell fate transition occurring during de novo root organogenesis in Arabidopsis

    Science.gov (United States)

    Chen, Lyuqin; Tong, Jianhua; Xiao, Langtao; Ruan, Ying; Liu, Jingchun; Zeng, Minhuan; Huang, Hai; Wang, Jia-Wei; Xu, Lin

    2016-01-01

    Many plant organs have the ability to regenerate a new plant after detachment or wounding via de novo organogenesis. During de novo root organogenesis from Arabidopsis thaliana leaf explants, endogenic auxin is essential for the fate transition of regeneration-competent cells to become root founder cells via activation of WUSCHEL-RELATED HOMEOBOX 11 (WOX11). However, the molecular events from leaf explant detachment to auxin-mediated cell fate transition are poorly understood. In this study, we used an assay to determine the concentration of indole-3-acetic acid (IAA) to provide direct evidence that auxin is produced after leaf explant detachment, a process that involves YUCCA (YUC)-mediated auxin biogenesis. Inhibition of YUC prevents expression of WOX11 and fate transition of competent cells, resulting in the blocking of rooting. Further analysis showed that YUC1 and YUC4 act quickly (within 4 hours) in response to wounding after detachment in both light and dark conditions and promote auxin biogenesis in both mesophyll and competent cells, whereas YUC5, YUC8, and YUC9 primarily respond in dark conditions. In addition, YUC2 and YUC6 contribute to rooting by providing a basal auxin level in the leaf. Overall, our study indicates that YUC genes exhibit a division of labour during de novo root organogenesis from leaf explants in response to multiple signals. PMID:27255928

  17. Chemical and biological studies of Kalanchoe pinnata (Lam.) growing in Bangladesh

    Institute of Scientific and Technical Information of China (English)

    Shazid M. Sharker; Mohammad K. Hossain; Mohammad R. Haque; Abu A. Chowdhury; Md. A. Kaisar; Choudhury M. Hasan; Mohammad A. Rashid

    2012-01-01

    Objective: To isolate compounds from K. pinnata and elucidate their structures and to explore preliminary antioxidant, antimicrobial, cytotoxic and thombolytic activities of extractives of the plant. Methods: The methanol extract of whole plant of K. pinnata has been subjected to different chromatographic separation and purification processes to isolate the secondary metabolites. The structures of the isolated compounds have been elucidated by extensive NMR studies. The free radical scavenging activity of the crude extract and its different Kupchan fractions were determined on stable radical DPPH. In vitro antimicrobial activity was determined by the disk diffusion method. Cytotoxicity screening has been performed against Artemia salina. Total phenolics content, membrane stabilizing activity and thombolytic activities were assessed by following established protocol. Results: The isolated compounds were identified as glut-5(6)-en-3-one, taraxerone, 3β-friedelanol, β-amyrin-3-acetate, 3,5,7,3',5'-pentahydroxyflavone and β-sitosterol. The chloroform soluble fraction showed potent antioxidant activity of (IC50=80.0 μg/mL) and significant cytotoxicity, while the crude extract demonstrated noticeable total polyphenol content (149.24 mg of GAE/gm of extractive), moderate membrane stabilizing activity and inhibition of clot lysis of blood. Conclusions: The obtained results rationalize the folkloric use of the plant and can be further investigated to isolate the active compounds responsible for the biological activities.

  18. Effects of phytohormones on mycelial growth and exopolysaccharide biosynthesis of medicinal mushroom Phellinus [corrected] linteus.

    Science.gov (United States)

    Guo, Xia; Zou, Xiang; Sun, Min

    2009-08-01

    Effects of phytohormones including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and 1-naphthaleneacetic [corrected] acid (NAA) on mycelial growth of medicinal mushroom Phellinus linteus were investigated. Under the optimal IAA, IBA and NAA concentration of 1.0, 1.5 and 5.0 mg/l, the maximal mycelial diameter reached 8.6 +/- 0.4, 7.3 +/- 2.6 and 9.0 +/- 1.0 mm, respectively. The mycelial biomass and exopolysaccharide (EPS) production with addition of 5.0 mg/l NAA in a shake flask were 6.24 +/- 0.18 g/l at 168 h and 0.86 +/-0.01 g/l at 192 h, which were enhanced by 15.98 and 56.36% compared to the control, respectively. However, the molecular weight and infrared spectrum of EPS were coincident with the control. Results indicated that NAA at the proper concentration was beneficial in stimulating mycelial growth and EPS biosynthesis, whereas it could not alter the molecular structure of EPS.

  19. Five New Cytotoxic Metabolites from the Marine Fungus Neosartorya pseudofischeri

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    Wen-Jian Lan

    2016-01-01

    Full Text Available The marine fungus Neosartorya pseudofischeri was isolated from Acanthaster planci from the South China Sea. In a preliminary bioactivity screening, the crude methanol extract of the fungal mycelia showed significant inhibitory activity against the Sf9 cell line from the fall armyworm Spodoptera frugiperda. Five novel compounds, including 5-olefin phenylpyropene A (1, 13-dehydroxylpyripyropene A (4, deacetylsesquiterpene (7, 5-formyl-6-hydroxy-8-isopropyl-2- naphthoic acid (9 and 6,8-dihydroxy-3-((1E,3E-penta-1,3-dien-1-ylisochroman-1-one (10, together with eleven known compounds, phenylpyropene A (2 and C (3, pyripyropene A (5, 7-deacetylpyripyropene A (6, (1S,2R,4aR,5R,8R,8aR-1,8a-dihydroxy-2-acetoxy-3,8-dimethyl-5- (prop-1-en-2-yl-1,2,4a, 5,6,7,8,8a-octahydronaphthalene (8, isochaetominine C (11, trichodermamide A (12, indolyl-3-acetic acid methyl ester (13, 1-acetyl-β-carboline (14, 1,2,3,4-tetrahydro-6-hydroxyl-2-methyl-l,3,4-trioxopyrazino[l,2-a]-indole (15 and fumiquinazoline F (16, were obtained. The structures of these compounds were determined mainly by MS and NMR data. The absolute configuration of 9 was assigned by the single-crystal X-ray diffraction studies. Compounds 1–11 and 15 showed significant cytotoxicity against the Sf9 cells from S. frugiperda.

  20. Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements.

    Science.gov (United States)

    López-Aparicio, S; Hak, C

    2013-05-01

    Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO2, O3, acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde>150 ppm; acetic acid ≈ 20-30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion.

  1. Halogenated auxins affect microtubules and root elongation in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    2000-01-01

    We studied the effect of 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA), a recently described root growth stimulator, and 5,6-dichloro-indole-3-acetic acid (DCIAA) on growth and microtubule (MT) organization in roots of Lactuca sativa L. DCIAA and indole-3-butyric acid (IBA) inhibited root elongation and depolymerized MTs in the cortex of the elongation zone, inhibited the elongation of stele cells, and promoted xylem maturation. Both auxins caused the plane of cell division to shift from anticlinal to periclinal. In contrast, TFIBA (100 micromolar) promoted elongation of primary roots by 40% and stimulated the elongation of lateral roots, even in the presence of IBA, the microtubular inhibitors oryzalin and taxol, or the auxin transport inhibitor naphthylphthalamic acid. However, TFIBA inhibited the formation of lateral root primordia. Immunostaining showed that TFIBA stabilized MTs orientation perpendicular to the root axis, doubled the cortical cell length, but delayed xylem maturation. The data indicate that the auxin-induced inhibition of elongation and swelling of roots results from reoriented phragmoplasts, the destabilization of MTs in elongating cells, and promotion of vessel formation. In contrast, TFIBA induced promotion of root elongation by enhancing cell length, prolonging transverse MT orientation, delaying cell and xylem maturation.

  2. Effects of sodium nitroprusside (SNP) pretreatment on UV-B stress tolerance in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Esringu, Aslıhan; Aksakal, Ozkan; Tabay, Dilruba; Kara, Ayse Aydan

    2016-01-01

    Ultraviolet-B (UV-B) radiation is one of the most important abiotic stress factors that could influence plant growth, development, and productivity. Nitric oxide (NO) is an important plant growth regulator involved in a wide variety of physiological processes. In the present study, the possibility of enhancing UV-B stress tolerance of lettuce seedlings by the exogenous application of sodium nitroprusside (SNP) was investigated. UV-B radiation increased the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and total phenolic concentrations, antioxidant capacity, and expression of phenylalanine ammonia lyase (PAL) gene in seedlings, but the combination of SNP pretreatment and UV-B enhanced antioxidant enzyme activities, total phenolic concentrations, antioxidant capacity, and PAL gene expression even more. Moreover, UV-B radiation significantly inhibited chlorophylls, carotenoid, gibberellic acid (GA), and indole-3-acetic acid (IAA) contents and increased the contents of abscisic acid (ABA), salicylic acid (SA), malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide radical (O2•(-)) in lettuce seedlings. When SNP pretreatment was combined with the UV-B radiation, we observed alleviated chlorophylls, carotenoid, GA, and IAA inhibition and decreased content of ABA, SA, MDA, H2O2, and O2•(-) in comparison to non-pretreated stressed seedlings.

  3. Phytohormone profile in Lactuca sativa and Brassica oleracea plants grown under Zn deficiency.

    Science.gov (United States)

    Navarro-León, Eloy; Albacete, Alfonso; Torre-González, Alejandro de la; Ruiz, Juan M; Blasco, Begoña

    2016-10-01

    Phytohormones, structurally diverse compounds, are involved in multiple processes within plants, such as controlling plant growth and stress response. Zn is an essential micronutrient for plants and its deficiency causes large economic losses in crops. Therefore, the purpose of this study was to analyse the role of phytohormones in the Zn-deficiency response of two economically important species, i.e. Lactuca sativa and Brassica oleracea. For this, these two species were grown hydroponically with different Zn-application rates: 10 μM Zn as control and 0.1 μM Zn as deficiency treatment and phytohormone concentration was determined by U-HPLC-MS. Zn deficiency resulted in a substantial loss of biomass in L. sativa plants that was correlated with a decline in growth-promoting hormones such as indole-3-acetic acid (IAA), cytokinins (CKs), and gibberellins (GAs). However these hormones increased or stabilized their concentrations in B. oleracea and could help to maintain the biomass in this species. A lower concentration of stress-signaling hormones such as ethylene precursor aminocyclopropane-1-carboxylic acid (ACC), abscisic acid (ABA), salicylic acid (SA) and jasmonic acid (JA) and also CKs might be involved in Zn uptake in L. sativa while a rise in GA4, isopentenyl adenine (iP), and ACC and a fall in JA and SA might contribute to a better Zn-utilization efficiency (ZnUtE), as observed in B. oleracea plants.

  4. Changes in the anti-inflammatory activity of soy isoflavonoid genistein versus genistein incorporated in two types of cyclodextrin derivatives

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    Danciu CorinaTiulea

    2012-06-01

    Full Text Available Abstract Background The isoflavonoid genistein represents the major active compound from soybean, the vegetal product from Glycine max (Fabaceae. The aim of this study is to prove that genistein was incorporated in two semisynthetic cyclodextrins, beta-cyclodextrin derivatives: hydroxypropyl-beta-cyclodextrin and randomly-methylated-beta-cyclodextrin as well as to compare the anti-inflammatory activity of genistein with that of genistein incorporated in these two types of semisynthetic cyclodextrins. Results The animal studies were conducted on 8-week old C57BL/6 J female mice. Inflammation was induced in both ears of each mouse by topical application of 10 micrograms 12-O-tetradecanoylphorbol-3-acetate dissolved in 0.1 ml solvent (acetone : dimethylsulfoxide in a molar ratio 9:1. Thirty minutes later treatment was applied. The inflammatory reaction was correlated with increased values in ear thickness. Treatment with genistein and genistein incorporated in the two cyclodextrins led to decreased values for ear thickness. Better anti-inflammatory action was found for the complexes of genistein. Both haematoxylin-eosin analysis and CD45 marker expression are in agreement with these findings. Conclusions Results allow concluding that genistein is an active anti-inflammatory phytocompound and its complexation with hydrophilic beta-cyclodextrin derivatives leads to a stronger anti-inflammatory activity.

  5. Glutathione synthesis is essential for pollen germination in vitro

    Science.gov (United States)

    2011-01-01

    Background The antioxidant glutathione fulfills many important roles during plant development, growth and defense in the sporophyte, however the role of this important molecule in the gametophyte generation is largely unclear. Bioinformatic data indicate that critical control enzymes are negligibly transcribed in pollen and sperm cells. Therefore, we decided to investigate the role of glutathione synthesis for pollen germination in vitro in Arabidopsis thaliana accession Col-0 and in the glutathione deficient mutant pad2-1 and link it with glutathione status on the subcellular level. Results The depletion of glutathione by buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis, reduced pollen germination rates to 2-5% compared to 71% germination in wildtype controls. The application of reduced glutathione (GSH), together with BSO, restored pollen germination and glutathione contents to control values, demonstrating that inhibition of glutathione synthesis is responsible for the decrease of pollen germination in vitro. The addition of indole-3-acetic acid (IAA) to media containing BSO restored pollen germination to control values, which demonstrated that glutathione depletion in pollen grains triggered disturbances in auxin metabolism which led to inhibition of pollen germination. Conclusions This study demonstrates that glutathione synthesis is essential for pollen germination in vitro and that glutathione depletion and auxin metabolism are linked in pollen germination and early elongation of the pollen tube, as IAA addition rescues glutathione deficient pollen. PMID:21439079

  6. Indolic Uremic Solutes Enhance Procoagulant Activity of Red Blood Cells through Phosphatidylserine Exposure and Microparticle Release

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    Chunyan Gao

    2015-10-01

    Full Text Available Increased accumulation of indolic uremic solutes in the blood of uremic patients contributes to the risk of thrombotic events. Red blood cells (RBCs, the most abundant blood cells in circulation, may be a privileged target of these solutes. However, the effect of uremic solutes indoxyl sulfate (IS and indole-3-acetic acid (IAA on procoagulant activity (PCA of erythrocyte is unclear. Here, RBCs from healthy adults were treated with IS and IAA (mean and maximal concentrations reported in uremic patients. Phosphatidylserine (PS exposure of RBCs and their microparticles (MPs release were labeled with Alexa Fluor 488-lactadherin and detected by flow cytometer. Cytosolic Ca2+ ([Ca2+] with Fluo 3/AM was analyzed by flow cytometer. PCA was assessed by clotting time and purified coagulation complex assays. We found that PS exposure, MPs generation, and consequent PCA of RBCs at mean concentrations of IS and IAA enhanced and peaked in maximal uremic concentrations. Moreover, 128 nM lactadherin, a PS inhibitor, inhibited over 90% PCA of RBCs and RMPs. Eryptosis or damage, by indolic uremic solutes was due to, at least partially, the increase of cytosolic [Ca2+]. Our results suggest that RBC eryptosis in uremic solutes IS and IAA plays an important role in thrombus formation through releasing RMPs and exposing PS. Lactadherin acts as an efficient anticoagulant in this process.

  7. In Vitro Micropropagation of the Medicinal Plant Physalis angulata L.

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    Owk ANIEL KUMAR

    2016-06-01

    Full Text Available Physalis angulata L. is an important medicinal herb. An efficient direct adventitious plant regeneration protocol was developed for large scale propagation using leaf disc as explants. The explants were cultured on MS basal medium supplemented with 0.25-3.0 mg/L 6-benzyl amino purine (BAP for primary shoot proliferation. Inclusion of indole-3-acetic acid (IAA and gibberellic acid (GA3 in the culture medium along with BAP promoted a higher rate of shoot multiplication. The maximum number of shoots was produced in MS + BAP (1.0 mg/L + IAA (0.5 mg/L + GA3 (0.20 mg/L after the third subculture. An average of 152.8 ± 0.40 shoots were produced from each leaf disc. For root induction the shootlets were transferred to MS medium supplemented with different concentrations of indole-3-butyric acid (IBA. The highest percentage of root induction was observed in 1.0 mg/L (IBA. Rooted plants were successfully established in the soil after hardening. The survival percentage of rooted plants on soil was found to be 85%. This result will facilitate the conservation and propagation of the important medicinal herb Physalis angulata L.

  8. Genome-wide identification, isolation and expression analysis of auxin response factor(ARF gene family in sweet orange (Citrus sinensis

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    si-bei eli

    2015-03-01

    Full Text Available Auxin response factors (ARFs are an important family of proteins in auxin-mediated response, with key roles in various physiological and biochemical processes. To date, a genome-wide overview of the ARF gene family in citrus was not available. A systematic analysis of this gene family in citrus was begun by carrying out a genome-wide search for the homologues of auxin response genes. A total of 19 non-redundant ARF genes (CiARF were identified and validated from the sweet orange genome. A comprehensive overview of the CiARF gene family was undertaken, including the gene structures, phylogeny, chromosome locations, conserved motifs, and cis-elements in promoter sequences. Furthermore, expression profiling using real-time PCR revealed many CiARF genes, albeit with different patterns depending on types of tissues and/or developmental stages. Comprehensive expression analysis of these genes was also performed under two hormone treatments using real-time PCR. Indole-3-acetic acid and N-1-napthylphthalamic acid treatment experiments revealed differential up-regulation and down-regulation, respectively, of the 19 citrus ARF genes in the callus of sweet orange. Our comprehensive analysis of ARF genes further elucidates the roles of CiARF family members in citrus growth and development.

  9. Activation of ethylene-responsive p-hydroxyphenylpyruvate dioxygenase leads to increased tocopherol levels during ripening in mango

    Science.gov (United States)

    Singh, Rajesh K.; Ali, Sharique A.; Nath, Pravendra; Sane, Vidhu A.

    2011-01-01

    Mango is characterized by high tocopherol and carotenoid content during ripening. From a cDNA screen of differentially expressing genes during mango ripening, a full-length p-hydroxyphenylpyruvate dioxygenase (MiHPPD) gene homologue was isolated that encodes a key enzyme in the biosynthesis of tocopherols. The gene encoded a 432-amino-acid protein. Transcript analysis during different stages of ripening revealed that the gene is ripening related and rapidly induced by ethylene. The increase in MiHPPD transcript accumulation was followed by an increase in tocopherol levels during ripening. The ripening-related increase in MiHPPD expression was also seen in response to abscisic acid and to alesser extent to indole-3-acetic acid. The expression of MiHPPD was not restricted to fruits but was also seen in other tissues such as leaves particularly during senescence. The strong ethylene induction of MiHPPD was also seen in young leaves indicating that ethylene induction of MiHPPD is tissue independent. Promoter analysis of MiHPPD gene in tomato discs and leaves of stable transgenic lines of Arabidopsis showed that the cis elements for ripening-related, ethylene-responsive, and senescence-related expression resided within the 1590 nt region upstream of the ATG codon. Functionality of the gene was demonstrated by the ability of the expressed protein in bacteria to convert p-hydroxyphenylpyruvate to homogentisate. These results provide the first evidence for HPPD expression during ripening of a climacteric fruit. PMID:21430290

  10. Ecdysteroid-containing food supplements from Cyanotis arachnoidea on the European market: evidence for spinach product counterfeiting

    Science.gov (United States)

    Hunyadi, Attila; Herke, Ibolya; Lengyel, Katalin; Báthori, Mária; Kele, Zoltán; Simon, András; Tóth, Gábor; Szendrei, Kálmán

    2016-12-01

    Phytoecdysteroids like 20-hydroxyecdysone (“ecdysterone”) can exert a mild, non-hormonal anabolic/adaptogenic activity in mammals, and as such, are frequently used in food supplements. Spinach is well-known for its relatively low ecdysteroid content. Cyanotis arachnoidea, a plant native in China, is among the richest sources of phytoecdysteroids, and extracts of this plant are marketed in tons per year amounts via the internet at highly competitive prices. Here we report the investigation of a series of food supplements produced in Germany and claimed to contain spinach extracts. Twelve ecdysteroids including two new compounds were isolated and utilized as marker compounds. A comparative analysis of the products with Cyanotis and spinach extracts provides evidence that they were manufactured from Cyanotis extracts instead of spinach as stated. Based on the chromatographic fingerprints, 20-hydroxyecdysone 2- and 3-acetate are suggested as diagnostic markers for related quality control. This case appears to represent an unusual type of dietary supplement counterfeiting: undeclared extracts from alternative plants would supposedly ‘guarantee’ product efficacy.

  11. CgOpt1, a putative oligopeptide transporter from Colletotrichum gloeosporioides that is involved in responses to auxin and pathogenicity

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    Maor Rudy

    2009-08-01

    Full Text Available Abstract Background The fungus Colletotrichum gloeosporioides f. sp. aeschynomene produces high levels of indole-3-acetic acid (IAA in axenic cultures and during plant infection. We generated a suppression subtractive hybridization library enriched for IAA-induced genes and identified a clone, which was highly expressed in IAA-containing medium. Results The corresponding gene showed similarity to oligopeptide transporters of the OPT family and was therefore named CgOPT1. Expression of CgOPT1 in mycelia was low, and was enhanced by external application of IAA. cgopt1-silenced mutants produced less spores, had reduced pigmentation, and were less pathogenic to plants than the wild-type strain. IAA enhanced spore formation and caused changes in colony morphology in the wild-type strain, but had no effect on spore formation or colony morphology of the cgopt1-silenced mutants. Conclusion Our results show that IAA induces developmental changes in C. gloeosporioides. These changes are blocked in cgopt1-silenced mutants, suggesting that this protein is involved in regulation of fungal response to IAA. CgOPT1 is also necessary for full virulence, but it is unclear whether this phenotype is related to auxin.

  12. Aminopropyl-modified mesoporous molecular sieves as efficient adsorbents for removal of auxins

    Science.gov (United States)

    Moritz, Michał; Geszke-Moritz, Małgorzata

    2015-03-01

    In the present study, mesoporous siliceous materials grafted with 3-aminopropyltriethoxysilane (APTES) were examined as sorbents for removal of chosen plant growth factors (auxins) such as 1-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). Four different types of mesoporous molecular sieves including SBA-15, PHTS, SBA-16 and MCF have been prepared via non-ionic surfactant-assisted soft templating method. Silica molecular sieves were thoroughly characterized by nitrogen adsorption-desorption analysis, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The maximum adsorption capacity (Qmax) for NAA, IAA and IBA was in the range from 51.0 to 140.8 mg/g and from 4.3 to 7.3 mg/g for aminopropyl-modified adsorbents and pure silicas, respectively. The best adsorption performance was observed for IAA entrapment using both APTES-functionalized SBA-15 and MCF matrices (Qmax of 140.8 and 137.0 mg/g, respectively) which can be ascribed to their larger pore volumes and pore diameters. Moreover, these silicas were characterized by the highest adsorption efficiency exceeding 90% at low pollutant concentration. The experimental points for adsorption of plant growth factors onto aminopropyl-modified mesoporous molecular sieves fitted well to the Langmuir equation.

  13. Effect of N Fertilizers on Root Growth and Endogenous Hormones in Strawberry

    Institute of Scientific and Technical Information of China (English)

    WANG Bo; LAI Tao; HUANG Qi-Wei; YANG Xing-Ming; SHEN Qi-Rong

    2009-01-01

    Endogenous hormones play an important role in the growth and development of roots. The objective of this research was to study the effect of four types of N fertilizers on the root growth of strawberry (Fragaria ananassa Duchesne) and the endogenous enzymes of indole-3-acetic acid (IAA), abscisic acid (ABA), and isopentenyl adenosine (iPA) in its roots and leaves using enzyme-linked immunosorbent assay. Application of all types of N fertilizers significantly depressed (P ≤ 0.05) root growth at 20 d after transplanting. Application of organic-inorganic fertilizer (OIF) as basal fertilizer had a significant negative effect (P ≤ 0.05) on root growth. The application of OIF and urea lowered the lateral root frequency in strawberry plants at 60 d (P ≤ 0.05) compared with the application of two organic fertilizers (OFA and OFB) and the control (CK). With the fertilizer treatments, there were the same concentrations of IAA and ABA in both roots and leaves at the initial growth stage (20 d), lower levels of IAA and ABA at the later stage (60 d), and higher iPA levels at all seedling stages as compared to those of CK. Thus, changes in the concentrations of endogenous phytohormones in strawberry plants could be responsible for the morphological changes of roots due to fertilization.

  14. Overexpression of Arabidopsis YUCCA6 in Potato Results in High-Auxin Developmental Phenotypes and Enhanced Resistance to Water Deficit

    Institute of Scientific and Technical Information of China (English)

    Jeong Im Kim; Dongwon Baek; Hyeong Cheol Park; Hyun Jin Chun; Dong-Ha Oh; Min Kyung Lee; Joon-Yung Cha

    2013-01-01

    Indole-3-acetic acid (IAA),a major plant auxin,is produced in both tryptophan-dependent and tryptophanindependent pathways.A major pathway in Arabidopsis thaliana generates IAA in two reactions from tryptophan.Step one converts tryptophan to indole-3-pyruvic acid (IPA) by tryptophan aminotransferases followed by a rate-limiting step converting IPA to IAA catalyzed by YUCCA proteins.We identified eight putative StYUC (Solanum tuberosum YUCCA)genes whose deduced amino acid sequences share 50%-70% identity with those of Arabidopsis YUCCA proteins.All include canonical,conserved YUCCA sequences:FATGY motif,FMO signature sequence,and FAD-binding and NADP-binding sequences.In addition,five genes were found with-50% amino acid sequence identity to Arabidopsis tryptophan aminotransferases.Transgenic potato (Solanum tuberosum cv.Jowon) constitutively overexpressing Arabidopsis AtYUC6 displayed high-auxin phenotypes such as narrow downward-curled leaves,increased height,erect stature,and longevity.Transgenic potato plants overexpressing AtYUC6 showed enhanced drought tolerance based on reduced water loss.The phenotype was correlated with reduced levels of reactive oxygen species in leaves.The results suggest a functional YUCCA pathway of auxin biosynthesis in potato that may be exploited to alter plant responses to the environment.

  15. A solvent extraction approach to recover acetic acid from mixed waste acids produced during semiconductor wafer process.

    Science.gov (United States)

    Shin, Chang-Hoon; Kim, Ju-Yup; Kim, Jun-Young; Kim, Hyun-Sang; Lee, Hyang-Sook; Mohapatra, Debasish; Ahn, Jae-Woo; Ahn, Jong-Gwan; Bae, Wookeun

    2009-03-15

    Recovery of acetic acid (HAc) from the waste etching solution discharged from silicon wafer manufacturing process has been attempted by using solvent extraction process. For this purpose 2-ethylhexyl alcohol (EHA) was used as organic solvent. In the pre-treatment stage >99% silicon and hydrofluoric acid was removed from the solution by precipitation. The synthesized product, Na(2)SiF(6) having 98.2% purity was considered of commercial grade having good market value. The waste solution containing 279 g/L acetic acid, 513 g/L nitric acid, 0.9 g/L hydrofluoric acid and 0.030 g/L silicon was used for solvent extraction study. From the batch test results equilibrium conditions for HAc recovery were optimized and found to be 4 stages of extraction at an organic:aqueous (O:A) ratio of 3, 4 stages of scrubbing and 4 stages of stripping at an O:A ratio of 1. Deionized water (DW) was used as stripping agent to elute HAc from organic phase. In the whole batch process 96.3% acetic acid recovery was achieved. Continuous operations were successfully conducted for 100 h using a mixer-settler to examine the feasibility of the extraction system for its possible commercial application. Finally, a complete process flowsheet with material balance for the separation and recovery of HAc has been proposed.

  16. Utilization of Enzyme-Immobilized Mesoporous Silica Nanocontainers (IBN-4 in Prodrug-Activated Cancer Theranostics

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    Bau-Yen Hung

    2015-12-01

    Full Text Available To develop a carrier for use in enzyme prodrug therapy, Horseradish peroxidase (HRP was immobilized onto mesoporous silica nanoparticles (IBN-4: Institute of Bioengineering and Nanotechnology, where the nanoparticle surfaces were functionalized with 3-aminopropyltrimethoxysilane and further conjugated with glutaraldehyde. Consequently, the enzymes could be stabilized in nanochannels through the formation of covalent imine bonds. This strategy was used to protect HRP from immune exclusion, degradation and denaturation under biological conditions. Furthermore, immobilization of HRP in the nanochannels of IBN-4 nanomaterials exhibited good functional stability upon repetitive use and long-term storage (60 days at 4 °C. The generation of functionalized and HRP-immobilized nanomaterials was further verified using various characterization techniques. The possibility of using HRP-encapsulated IBN-4 materials in prodrug cancer therapy was also demonstrated by evaluating their ability to convert a prodrug (indole-3- acetic acid (IAA into cytotoxic radicals, which triggered tumor cell apoptosis in human colon carcinoma (HT-29 cell line cells. A lactate dehydrogenase (LDH assay revealed that cells could be exposed to the IBN-4 nanocomposites without damaging their membranes, confirming apoptotic cell death. In summary, we demonstrated the potential of utilizing large porous mesoporous silica nanomaterials (IBN-4 as enzyme carriers for prodrug therapy.

  17. Influence of growth regulators in biomass production and volatile profile of in vitro plantlets of Thymus vulgaris L.

    Science.gov (United States)

    Affonso, Vanessa Ribeiro; Bizzo, Humberto Ribeiro; Lage, Celso Luiz Salgueiro; Sato, Alice

    2009-07-22

    In vitro shoots of thyme (Thymus vulgaris L.) were established, and the effects of the auxin indole-3-acetic (IAA) acid and the cytokinins benzyladenine (BA), zeatin (ZEA), and kinetin (KIN) at 1.0, 5.0, and 10.0 microM on rooting, biomass production, and volatile compounds production by these plants were investigated. The volatiles were extracted by solid phase microextraction (SPME) and analyzed by gas chromatography. The highest biomass shoot growth was obtained with BA at 5.0 microM, while IAA at all concentrations tested achieved 100% rooting frequency. The three major compounds were gamma-terpinene (22.8-38.8%), p-cymene (13.8-27.9%), and thymol (6.5-29.0%). Quantitative changes of these compounds were observed in response to the effect of varying growth regulators concentrations in the culture medium. Growing Thymus vulgaris L. plants in media supplemented with IAA at 1.0 microM increased volatile compounds such as thymol by 315%. Nevertheless, the same major compounds were produced in all treatments and no qualitative changes were observed in the volatile profile of thyme plants.

  18. Effects of exogenous ABA application on post-anthesis dry matter redistribution and grain starch accumulation of winter wheat with different staygreen characteristics

    Directory of Open Access Journals (Sweden)

    Dongqing Yang

    2014-04-01

    Full Text Available The objective of this study was to investigate whether and how exogenous abscisic acid (ABA is involved in mediating starch accumulation in the grain and redistribution of carbohydrates during grain filling of two wheat cultivars with different staygreen characteristics. At blooming stage, plants of Wennong 6 (a staygreen cultivar and Jimai 20 (control were sprayed with 10 mg L− 1 abscisic acid (ABA for 3 days. The application of ABA significantly (P < 0.05 increased grain filling rate, starch accumulation rate and content, remobilization of dry matters to kernels, and 1000-grain weight of the two cultivars. Exogenous ABA markedly (P < 0.05 increased grain yield at maturity, and Wennong 6 and Jiami 20 showed 14.14% and 4.86% higher compared yield than the control. Dry matter accumulation after anthesis of Wennong 6 was also significantly (P < 0.05 influenced by exogenous ABA, whereas that of Jimai 20 was unchanged. Application of ABA increased endogenous zeatin riboside (ZR content 7 days after anthesis (DAA, and spraying ABA significantly increased endogenous indole-3-acetic acid (IAA and ABA contents from 7 to 21 DAA and decreased gibberellin (GA3 content at 14 DAA, but increased GA3 content from 21 to 35 DAA. The results suggested that increased yield of staygreen was due to greater starch assimilation owing to a higher filling rate and longer grain-filling duration.

  19. The relationship between polyamines and hormones in the regulation of wheat grain filling.

    Directory of Open Access Journals (Sweden)

    Yang Liu

    Full Text Available The grain weight of wheat is strongly influenced by filling. Polyamines (PA are involved in regulating plant growth. However, the effects of PA on wheat grain filling and its mechanism of action are unclear. The objective of the present study was to investigate the relationship between PAs and hormones in the regulation of wheat grain filling. Three PAs, spermidine (Spd, spermine (Spm, and putrescine (Put, were exogenously applied, and the grain filling characteristics and changes in endogenous PA and hormones, i.e., indole-3-acetic acid (IAA, zeatin (Z + zeatin riboside (ZR, abscisic acid (ABA, ethylene (ETH and gibberellin 1+4 (GAs, were quantified during wheat grain filling. Exogenous applications of Spd and Spm significantly increased the grain filling rate and weight, but exogenous Put had no significant effects on these measures. Exogenous Spd and Spm significantly increased the endogenous Spd, Spm, Z+ZR, ABA, and IAA contents and significantly decreased ETH evolution in grains. The endogenous Spd, Spm and Z+ZR contents were positively and significantly correlated with the grain filling rate and weight of wheat, and the endogenous ETH evolution was negatively and significantly correlated with the wheat grain filling rate and weight. Based upon these results, we concluded that PAs were involved in the balance of hormones that regulated the grain filling of wheat.

  20. Metabolite Profiling of Barley Grains Subjected to Water Stress: To Explain the Genotypic Difference in Drought-Induced Impacts on Malting Quality

    Directory of Open Access Journals (Sweden)

    Xiaojian Wu

    2017-09-01

    Full Text Available Grain weight and protein content will be reduced and increased, respectively, when barley is subjected to water stress after anthesis, consequently deteriorating the malt quality. However, such adverse impact of water stress differs greatly among barley genotypes. In this study, two Tibetan wild barley accessions and two cultivated varieties differing in water stress tolerance were used to investigate the genotypic difference in metabolic profiles during grain-filling stage under drought condition. Totally, 71 differently accumulated metabolites were identified, including organic acids, amino acids/amines, and sugars/sugar alcohols. Their relative contents were significantly affected by water stress for all genotypes and differed distinctly between the wild and cultivated barleys. The principal component analysis of metabolites indicated that the Tibetan wild barley XZ147 possessed a unique response to water stress. When subjected to water stress, the wild barley XZ147 showed the most increase of β-amylase activity among the four genotypes, as a result of its higher lysine content, less indole-3-acetic acid (IAA biosynthesis, more stable H2O2 homeostasis, and more up-regulation of BMY1 gene. On the other hand, XZ147 had the most reduction of β-glucan content under water stress than the other genotypes, which could be explained by the faster grain filling process and the less expression of β-glucan synthase gene GSL7. All these results indicated a great potential for XZ147 in barley breeding for improving water stress tolerance.

  1. Effects of Auxins on PIN-FORMED2 (PIN2) Dynamics Are Not Mediated by Inhibiting PIN2 Endocytosis.

    Science.gov (United States)

    Jásik, Ján; Bokor, Boris; Stuchlík, Stanislav; Mičieta, Karol; Turňa, Ján; Schmelzer, Elmon

    2016-10-01

    By using the photoconvertible fluorescence protein Dendra2 as a tag we demonstrated that neither the naturally occurring auxins indole-3-acetic acid and indole-3-butyric acid, nor the synthetic auxin analogs 1-naphthaleneacetic acid and 2,4-dichlorophenoxyacetic acid nor compounds inhibiting polar auxin transport such as 2,3,5-triiodobenzoic acid and 1-N-naphthylphthalamic acid, were able to inhibit endocytosis of the putative auxin transporter PIN-FORMED2 (PIN2) in Arabidopsis (Arabidopsis thaliana) root epidermis cells. All compounds, except Indole-3-butyric acid, repressed the recovery of the PIN2-Dendra2 plasma membrane pool after photoconversion when they were used in high concentrations. The synthetic auxin analogs 1-naphthaleneacetic acid and 2,4-dichlorophenoxyacetic acid showed the strongest inhibition. Auxins and auxin transport inhibitors suppressed also the accumulation of both newly synthesized and endocytotic PIN2 pools in Brefeldin A compartments (BFACs). Furthermore, we demonstrated that all compounds are also interfering with BFAC formation. The synthetic auxin analogs caused the highest reduction in the number and size of BFACs. We concluded that auxins and inhibitors of auxin transport do affect PIN2 turnover in the cells, but it is through the synthetic rather than the endocytotic pathway. The study also confirmed inappropriateness of the BFA-based approach to study PIN2 endocytosis because the majority of PIN2 accumulating in BFACs is newly synthesized and not derived from the plasma membrane. © 2016 American Society of Plant Biologists. All Rights Reserved.

  2. Analyses of Indole Compounds in Sugar Cane (Saccharum officinarum L. Juice by High Performance Liquid Chromatography and Liquid Chromatography-Mass Spectrometry after Solid-Phase Extraction

    Directory of Open Access Journals (Sweden)

    Jean Wan Hong Yong

    2017-03-01

    Full Text Available Simultaneous quantitative analysis of 10 indole compounds, including indole-3-acetic acid (IAA, one of the most important naturally occurring auxins and some of its metabolites, by high performance liquid chromatography (HPLC and liquid chromatography-mass spectrometry (LC-MS after solid-phase extraction (SPE was reported for the first time. The analysis was carried out using a reverse phase HPLC gradient elution, with an aqueous mobile phase (containing 0.1% formic acid modified by methanol. Furthermore, a novel SPE procedure was developed for the pre-concentration and purification of indole compounds using C18 SPE cartridges. The combination of SPE, HPLC, and LC-MS was applied to screen for the indole compounds present in sugar cane (Saccharum officinarum L. juice, a refreshing beverage with various health benefits. Finally, four indole compounds were successfully detected and quantified in sugar cane juice by HPLC, which were further unequivocally confirmed by LC-MS/MS experiments operating in the multiple reaction monitoring (MRM mode.

  3. Halogenated auxins affect microtubules and root elongation in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    2000-01-01

    We studied the effect of 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA), a recently described root growth stimulator, and 5,6-dichloro-indole-3-acetic acid (DCIAA) on growth and microtubule (MT) organization in roots of Lactuca sativa L. DCIAA and indole-3-butyric acid (IBA) inhibited root elongation and depolymerized MTs in the cortex of the elongation zone, inhibited the elongation of stele cells, and promoted xylem maturation. Both auxins caused the plane of cell division to shift from anticlinal to periclinal. In contrast, TFIBA (100 micromolar) promoted elongation of primary roots by 40% and stimulated the elongation of lateral roots, even in the presence of IBA, the microtubular inhibitors oryzalin and taxol, or the auxin transport inhibitor naphthylphthalamic acid. However, TFIBA inhibited the formation of lateral root primordia. Immunostaining showed that TFIBA stabilized MTs orientation perpendicular to the root axis, doubled the cortical cell length, but delayed xylem maturation. The data indicate that the auxin-induced inhibition of elongation and swelling of roots results from reoriented phragmoplasts, the destabilization of MTs in elongating cells, and promotion of vessel formation. In contrast, TFIBA induced promotion of root elongation by enhancing cell length, prolonging transverse MT orientation, delaying cell and xylem maturation.

  4. Jasmonoyl-L-Tryptophan Disrupts IAA Activity through the AUX1 Auxin Permease

    Directory of Open Access Journals (Sweden)

    Paul Staswick

    2017-05-01

    Full Text Available Amide-linked conjugates between tryptophan (Trp and jasmonic (JA or indole-3-acetic (IAA acids interfered with gravitropism and other auxin-dependent activities in Arabidopsis, but the mechanism was unclear. To identify structural features necessary for activity several additional Trp conjugates were synthesized. The phenylacetic acid (PAA conjugate was active, while several others were not. Common features of active conjugates is that they have ring structures that are linked to Trp through an acetic acid side chain, while longer or shorter linkages are inactive or less active. A dominant mutant, called tryptophan conjugate response1-D that is insensitive to JA-Trp, but still sensitive to other active conjugates, was identified and the defect was found to be a substitution of Asn for Asp456 in the C-terminal domain of the IAA cellular permease AUX1. Mutant seedling primary root growth in the absence of added conjugate was 15% less than WT, but otherwise plant phenotype appeared normal. These results suggest that JA-Trp disrupts AUX1 activity, but that endogenous JA-Trp has only a minor role in regulating plant growth. In contrast with IAA- and JA-Trp, which are present at <2 pmole g-1 FW, PAA-Trp was found at about 30 pmole g-1 FW. The latter, or other undiscovered Trp conjugates, may still have important endogenous roles, possibly helping to coordinate other pathways with auxin response.

  5. Endogenous auxin and jasmonic acid levels are differentially modulated by abiotic stresses in rice

    Directory of Open Access Journals (Sweden)

    Hao eDu

    2013-10-01

    Full Text Available Abiotic stresses such as drought, salinity, and adverse temperatures are major limiting factors for plant growth and reproduction. Plant responses to these stresses are coordinated by arrays of regulatory networks including the induction of endogenous abscisic acid (ABA, a well documented phytohormone for stress responses. However, whether or how these abiotic stresses affect the endogenous biosynthesis or metabolism of other phytohormones remains largely unknown. Here, we report the changes of endogenous indole-3-acetic acid (IAA and jasmonic acid (JA levels and expression of genes related to the biosynthesis or signalling of these hormones in rice under various abiotic stress conditions. The IAA content was decreased after drought stress, but it was significantly increased under cold and heat stresses. And the auxin-regulated gravitropism of root tip was inhibited by cold stress. Many genes involved in the IAA biosynthesis and signalling were changed in transcript level under these stresses, and the changes were essentially in agreement with the change of endogenous IAA level. Interestingly, the endogenous JA content was increased markedly under drought and cold stresses, but it was reduced by heat stress. Accordingly, many genes involved in JA biosynthesis and signalling were induced by drought and cold treatment but these genes were significantly suppressed by heat stress. We concluded that endogenous levels of IAA and JA were differentially regulated by abiotic stresses in rice, implying diverse roles of these hormones in stress responses.

  6. AUX/LAX family of auxin influx carriers-an overview

    Directory of Open Access Journals (Sweden)

    Ranjan eSwarup

    2012-10-01

    Full Text Available Auxin regulates several aspects of plant growth and development. Auxin is unique among plant hormones for exhibiting polar transport. Indole-3-acetic acid, the major form of auxin in higher plants, is a weak acid and its intercellular movement is facilitated by auxin influx and efflux carriers.. Polarity of auxin movement is provided by asymmetric localisation of auxin carriers (mainly PIN efflux carriers. PIN-FORMED (PIN and P-GLYCOPROTEIN (PGP family of proteins are major auxin efflux carriers whereas AUXIN1/LIKE-AUX1 (AUX/LAX are major auxin influx carriers.. Genetic and biochemical evidence show that each member of the AUX/LAX family is a functional auxin influx carrier and mediate auxin related developmental programmes in different organs and tissues. Of the four AUX/LAX genes, AUX1 regulates root gravitropism, root hair development and leaf phyllotaxy whereas LAX2 regulates vascular development in cotyledons. Both AUX1 and LAX3 have been implicated in lateral root development as well as apical hook formation whereas both AUX1 and LAX1 and possibly LAX2 are required for leaf phyllotactic patterning.

  7. Enzyme-encapsulated silica nanoparticle for cancer chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Yi-Rong; Ho, Wei-Jen; Chao, Jiun-Shuan; Yuan, Chiun-Jye, E-mail: cjyuan@mail.nctu.edu.tw [National Chiao Tung University, Department of Biological Science and Technology, Taiwan (China)

    2012-03-15

    A novel horseradish peroxidase-encapsulated silica nanoparticle (SNP) was generated in this study under relatively mild conditions. The generated enzyme-encapsulated SNP were relatively uniform in size (average 70 {+-} 14.3 nm), monodispersed, and spherical, as characterized by transmission electron microscopy and scanning electron microscopy. The horseradish peroxidase encapsulated in silica nanoparticle exhibits biological properties, such as a pH-dependent activity profile and k{sub m} value, similar to that of free enzymes. Furthermore, enzyme-encapsulated SNP exhibited good operational stability for the repetitive usage with a relative standard deviation of 5.1 % (n = 10) and a high stability for long term storage (>60 days) at 4 Degree-Sign C. The feasibility of using enzyme-encapsulated SNP in prodrug cancer therapy was also demonstrated by its capability to convert the prodrug indole-3-acetic acid into cytotoxic peroxyl radicals and trigger the death of tumor cells. These results indicate that the developed enzyme-encapsulated SNP has potential in the applications of prodrug cancer therapy.

  8. Auxin-activated NADH oxidase activity of soybean plasma membranes is distinct from the constitutive plasma membrane NADH oxidase and exhibits prion-like properties

    Science.gov (United States)

    Morre, D. James; Morre, Dorothy M.; Ternes, Philipp

    2003-01-01

    The hormone-stimulated and growth-related cell surface hydroquinone (NADH) oxidase activity of etiolated hypocotyls of soybeans oscillates with a period of about 24 min or 60 times per 24-h day. Plasma membranes of soybean hypocotyls contain two such NADH oxidase activities that have been resolved by purification on concanavalin A columns. One in the apparent molecular weight range of 14-17 kDa is stimulated by the auxin herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The other is larger and unaffected by 2,4-D. The 2,4-D-stimulated activity absolutely requires 2,4-D for activity and exhibits a period length of about 24 min. Also exhibiting 24-min oscillations is the rate of cell enlargement induced by the addition of 2,4-D or the natural auxin indole-3-acetic acid (IAA). Immediately following 2,4-D or IAA addition, a very complex pattern of oscillations is frequently observed. However, after several hours a dominant 24-min period emerges at the expense of the constitutive activity. A recruitment process analogous to that exhibited by prions is postulated to explain this behavior.

  9. WOX5-1AA17 Feedback Circuit-Mediated CellularAuxin Response Is Crucial for the Patterning ofRoot Stem Cell Niches in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    In plants, the patterning of stem cell-enriched meristems requires a graded auxin response maximum thatemerges from the concerted action of polar auxin transport, auxin biosynthesis, auxin metabolism, and cellular auxinresponse machinery. However, mechanisms underlying this auxin response maximum-mediated root stem cell mainte-nance are not fully understood. Here, we present unexpected evidence that WUSCHEL-RELATED HOMEOBOX 5 (WOX5)transcription factor modulates expression of auxin biosynthetic genes in the quiescent center (QC) of the root and thusprovides a robust mechanism for the maintenance of auxin response maximum in the root tip. This WOX5 action is bal-anced through the activity of indole-3-acetic acid 17 (IAA17) auxin response repressor. Our combined genetic, cell biol-ogy, and computational modeling studies revealed a previously uncharacterized feedback loop linking WOX5-mediatedauxin production to IAA17-dependent repression of auxin responses. This WOX5-1AA17 feedback circuit further assuresthe maintenance of auxin response maximum in the root tip and thereby contributes to the maintenance of distal stemcell (DSC) populations. Our experimental studies and in silico computer simulations both demonstrate that the WOX5-iAA17 feedback circuit is essential for the maintenance of auxin gradient in the root tip and the auxin-mediated root DSCdifferentiation.

  10. Auxin induces cell proliferation in an experimental model of mammalian renal tubular epithelial cells.

    Science.gov (United States)

    Cernaro, Valeria; Medici, Maria Antonietta; Leonello, Giuseppa; Buemi, Antoine; Kohnke, Franz Heinrich; Villari, Antonino; Santoro, Domenico; Buemi, Michele

    2015-06-01

    Indole-3-acetic acid is the main auxin produced by plants and plays a key role in the plant growth and development. This hormone is also present in humans where it is considered as a uremic toxin deriving from tryptophan metabolism. However, beyond this peculiar aspect, the involvement of auxin in human pathophysiology has not been further investigated. Since it is a growth hormone, we evaluated its proliferative properties in an in vitro model of mammalian renal tubular epithelial cells. We employed an experimental model of renal tubular epithelial cells belonging to the LLC-PK1 cell line that is derived from the kidney of healthy male pig. Growth effects of auxin against LLC-PK1 cell lines were determined by a rapid colorimetric assay. Increasing concentrations of auxin (to give a final concentration from 1 to 1000 ng/mL) were added and microplates were incubated for 72 h. Each auxin concentration was assayed in four wells and repeated four times. Cell proliferation significantly increased, compared to control cells, 72 h after addition of auxin to cultured LLC-PK1 cells. Statistically significant values were observed when 100 ng/mL (p auxin influences cell growth not only in plants, where its role is well documented, but also in mammalian cell lines. This observation opens new scenarios in the field of tissue regeneration and may stimulate a novel line of research aiming at investigating whether this hormone really influences human physiology and pathophysiology and in particular, kidney regeneration.

  11. Genome-wide identification, expression analysis of auxin-responsive GH3 family genes in maize (Zea mays L.) under abiotic stresses.

    Science.gov (United States)

    Feng, Shangguo; Yue, Runqing; Tao, Sun; Yang, Yanjun; Zhang, Lei; Xu, Mingfeng; Wang, Huizhong; Shen, Chenjia

    2015-09-01

    Auxin is involved in different aspects of plant growth and development by regulating the expression of auxin-responsive family genes. As one of the three major auxin-responsive families, GH3 (Gretchen Hagen3) genes participate in auxin homeostasis by catalyzing auxin conjugation and bounding free indole-3-acetic acid (IAA) to amino acids. However, how GH3 genes function in responses to abiotic stresses and various hormones in maize is largely unknown. Here, the latest updated maize (Zea mays L.) reference genome sequence was used to characterize and analyze the ZmGH3 family genes from maize. The results showed that 13 ZmGH3 genes were mapped on five maize chromosomes (total 10 chromosomes). Highly diversified gene structures and tissue-specific expression patterns suggested the possibility of function diversification for these genes in response to environmental stresses and hormone stimuli. The expression patterns of ZmGH3 genes are responsive to several abiotic stresses (salt, drought and cadmium) and major stress-related hormones (abscisic acid, salicylic acid and jasmonic acid). Various environmental factors suppress auxin free IAA contents in maize roots suggesting that these abiotic stresses and hormones might alter GH3-mediated auxin levels. The responsiveness of ZmGH3 genes to a wide range of abiotic stresses and stress-related hormones suggested that ZmGH3s are involved in maize tolerance to environmental stresses.

  12. Auxin response factors.

    Science.gov (United States)

    Chandler, John William

    2016-05-01

    Auxin signalling involves the activation or repression of gene expression by a class of auxin response factor (ARF) proteins that bind to auxin response elements in auxin-responsive gene promoters. The release of ARF repression in the presence of auxin by the degradation of their cognate auxin/indole-3-acetic acid repressors forms a paradigm of transcriptional response to auxin. However, this mechanism only applies to activating ARFs, and further layers of complexity of ARF function and regulation are being revealed, which partly reflect their highly modular domain structure. This review summarizes our knowledge concerning ARF binding site specificity, homodimer and heterodimer multimeric ARF association and cooperative function and how activator ARFs activate target genes via chromatin remodelling and evolutionary information derived from phylogenetic comparisons from ARFs from diverse species. ARFs are regulated in diverse ways, and their importance in non-auxin-regulated pathways is becoming evident. They are also embedded within higher-order transcription factor complexes that integrate signalling pathways from other hormones and in response to the environment. The ways in which new information concerning ARFs on many levels is causing a revision of existing paradigms of auxin response are discussed.

  13. Physcomitrella patens auxin conjugate synthetase (GH3) double knockout mutants are more resistant to Pythium infection than wild type.

    Science.gov (United States)

    Mittag, Jennifer; Šola, Ivana; Rusak, Gordana; Ludwig-Müller, Jutta

    2015-07-01

    Auxin homeostasis is involved in many different plant developmental and stress responses. The auxin amino acid conjugate synthetases belonging to the GH3 family play major roles in the regulation of free indole-3-acetic acid (IAA) levels and the moss Physcomitrella patens has two GH3 genes in its genome. A role for IAA in several angiosperm--pathogen interactions was reported, however, in a moss--oomycete pathosystem it had not been published so far. Using GH3 double knockout lines we have investigated the role of auxin homeostasis during the infection of P. patens with the two oomycete species, Pythium debaryanum and Pythium irregulare. We show that infection with P. debaryanum caused stronger disease symptoms than with P. irregulare. Also, P. patens lines harboring fusion constructs of an auxin-inducible promoter from soybean (GmGH3) with a reporter (ß-glucuronidase) showed higher promoter induction after P. debaryanum infection than after P. irregulare, indicating a differential induction of the auxin response. Free IAA was induced upon P. debaryanum infection in wild type by 1.6-fold and in two GH3 double knockout (GH3-doKO) mutants by 4- to 5-fold. All GH3-doKO lines showed a reduced disease symptom progression compared to wild type. Since P. debaryanum can be inhibited in growth on medium containing IAA, these data might indicate that endogenous high auxin levels in P. patens GH3-doKO mutants lead to higher resistance against the oomycete.

  14. Basipetal auxin transport is required for gravitropism in roots of Arabidopsis

    Science.gov (United States)

    Rashotte, A. M.; Brady, S. R.; Reed, R. C.; Ante, S. J.; Muday, G. K.; Davies, E. (Principal Investigator)

    2000-01-01

    Auxin transport has been reported to occur in two distinct polarities, acropetally and basipetally, in two different root tissues. The goals of this study were to determine whether both polarities of indole-3-acetic acid (IAA) transport occur in roots of Arabidopsis and to determine which polarity controls the gravity response. Global application of the auxin transport inhibitor naphthylphthalamic acid (NPA) to roots blocked the gravity response, root waving, and root elongation. Immediately after the application of NPA, the root gravity response was completely blocked, as measured by an automated video digitizer. Basipetal [(3)H]IAA transport in Arabidopsis roots was inhibited by NPA, whereas the movement of [(14)C]benzoic acid was not affected. Inhibition of basipetal IAA transport by local application of NPA blocked the gravity response. Inhibition of acropetal IAA transport by application of NPA at the root-shoot junction only partially reduced the gravity response at high NPA concentrations. Excised root tips, which do not receive auxin from the shoot, exhibited a normal response to gravity. The Arabidopsis mutant eir1, which has agravitropic roots, exhibited reduced basipetal IAA transport but wild-type levels of acropetal IAA transport. These results support the hypothesis that basipetally transported IAA controls root gravitropism in Arabidopsis.

  15. Studies on the Rice LEAF INCLINATION1 (LC1),an IAA-amido Synthetase, Reveal the Effects of Auxin in Leaf Inclination Control

    Institute of Scientific and Technical Information of China (English)

    Shu-Qing Zhao; Jing-Jing Xiang; Hong-Wei Xue

    2013-01-01

    The angle of rice leaf inclination is an important agronomic trait and closely related to the yields and architecture of crops.Although few mutants with altered leaf angles have been reported,the molecular mechanism remains to be elucidated,especially whether hormones are involved in this process.Through genetic screening,a rice gain-offunction mutant leaf inclination1,Ic1-D,was identified from the Shanghai T-DNA Insertion Population (SHIP).Phenotypic analysis confirmed the exaggerated leaf angles of Ic1-D due to the stimulated cell elongation at the lamina joint.LC1 is transcribed in various tissues and encodes OsGH3-1,an indole-3-acetic acid (IAA) amido synthetase,whose homolog of Arabidopsis functions in maintaining the auxin homeostasis by conjugating excess IAA to various amino acids.Indeed,recombinant LC1 can catalyze the conjugation of IAA to Ala,Asp,and Asn in vitro,which is consistent with the decreased free IAA amount in Ic1-D mutant.Ic1-D is insensitive to IAA and hypersensitive to exogenous BR,in agreement with the microarray analysis that reveals the altered transcriptions of genes involved in auxin signaling and BR biosynthesis.These results indicate the crucial roles of auxin homeostasis in the leaf inclination control.

  16. The role of auxin and ethylene for gravitropic differential growth of coleoptiles and roots of rye- and maize seedlings

    Science.gov (United States)

    Edelmann, H. G.; Sabovljevic, A.; Njio, G.; Roth, U.

    The relevance of auxin and ethylene for differential gravitropic growth has been analyzed both in shoots and roots of etiolated rye- and maize seedlings. As previously demonstrated for indolyl-3-acetic acid (IAA), incubation of coleoptiles in dichlorophenoxy acetic acid (2,4-D) resulted in a two- to threefold length increase compared to water controls. In spite of this immense effect on elongation growth, gravi-curvature was similar to water controls. In contrast, inhibition of ethylene synthesis prevented differential growth of abraded coleoptiles as well as of roots without a significant inhibiting effect on elongation. Inhibition of ethylene perception in horizontally stimulated maize roots growing on surfaces eliminated the capacity of the roots to adapt growth to the surface and a vertical orientation of the root tip. This effect is accompanied by up- and down-regulation of a number of proteins as detected with the 2D-MALDI-TOF (matrix-assisted laser desorption ionization- time of flight) method. Exogenous ethylene inhibited growth but enhanced gravitropic curvature in roots that were "freely" gravistimulated in a horizontal position, exhibiting a pronounced "waving" behavior. Together the data challenge the regulatory relevance of IAA-redistribution for gravitropic differential growth. They corroborate the crucial regulatory relevance of ethylene for gravitropic growth, in both roots and coleoptiles.

  17. Genome-wide identification, expression analysis of auxin-responsive GH3 family genes in maize (Zea mays L.) under abiotic stresses

    Institute of Scientific and Technical Information of China (English)

    Shangguo Feng; Runqing Yue; Sun Tao Yanjun Yang; Lei Zhang; Mingfeng Xu; Huizhong Wang; Chenjia Shen

    2015-01-01

    Auxin is involved in different aspects of plant growth and development by regulating the expression of auxin-responsive family genes. As one of the three major auxin-responsive families, GH3 (Gretchen Hagen3) genes participate in auxin homeostasis by catalyzing auxin conjugation and bounding free indole-3-acetic acid (IAA) to amino acids. However, how GH3 genes function in responses to abiotic stresses and various hormones in maize is largely unknown. Here, the latest updated maize (Zea mays L.) reference genome sequence was used to characterize and analyze the ZmGH3 family genes from maize. The results showed that 13 ZmGH3 genes were mapped on five maize chromosomes (total 10 chromosomes). Highly diversified gene structures and tissue-specific expression patterns suggested the possibility of function diversification for these genes in response to environmental stresses and hormone stimuli. The expression patterns of ZmGH3 genes are responsive to several abiotic stresses (salt, drought and cadmium) and major stress-related hormones (abscisic acid, salicylic acid and jasmonic acid). Various environmental factors suppress auxin free IAA contents in maize roots suggesting that these abiotic stresses and hormones might alter GH3-mediated auxin levels. The respon-siveness of ZmGH3 genes to a wide range of abiotic stresses and stress-related hormones suggested that ZmGH3s are involved in maize tolerance to environmental stresses.

  18. Light inhibits gravity-regulated peg formation and asymmetric mRNA accumulation of auxin-inducible CsIAA1 in the cortex of the transition zone in cucumber seedlings

    Science.gov (United States)

    Fujii, Nobuharu; Saito, Yuko; Miyazawa, Yutaka; Takahashi, Hideyuki

    When cucumber seedlings are grown horizontally, a specialized protuberance, termed the peg, develops on the lower side of the transition zone between the hypocotyl and the root. Gravimorphogenesis regulates the lateral positioning of the peg in the transition zone and it has been suggested that auxin plays an important role in peg formation in cucumber seedlings. Here, we found that light inhibited auxin-regulated peg formation. In the transition zone of horizontally positioned cucumber seedlings grown in the dark, we detected an asymmetric accumulation of mRNA from the auxin-inducible gene CsIAA1 in the epidermis and cortex. However, in seedlings grown under illumination, this asymmetry was greatly reduced. In dark- and light-grown seedlings, application of 10 -3 M indole-3-acetic acid induced peg formation on both the lower and upper sides of the transition zone. These results suggest that light inhibits peg formation via modification of auxin distribution and/or levels in the transition zone of cucumber seedlings.

  19. Flavonoids and Auxin Transport Inhibitors Rescue Symbiotic Nodulation in the Medicago truncatula Cytokinin Perception Mutant cre1.

    Science.gov (United States)

    Ng, Jason Liang Pin; Hassan, Samira; Truong, Thy T; Hocart, Charles H; Laffont, Carole; Frugier, Florian; Mathesius, Ulrike

    2015-08-01

    Initiation of symbiotic nodules in legumes requires cytokinin signaling, but its mechanism of action is largely unknown. Here, we tested whether the failure to initiate nodules in the Medicago truncatula cytokinin perception mutant cre1 (cytokinin response1) is due to its altered ability to regulate auxin transport, auxin accumulation, and induction of flavonoids. We found that in the cre1 mutant, symbiotic rhizobia cannot locally alter acro- and basipetal auxin transport during nodule initiation and that these mutants show reduced auxin (indole-3-acetic acid) accumulation and auxin responses compared with the wild type. Quantification of flavonoids, which can act as endogenous auxin transport inhibitors, showed a deficiency in the induction of free naringenin, isoliquiritigenin, quercetin, and hesperetin in cre1 roots compared with wild-type roots 24 h after inoculation with rhizobia. Coinoculation of roots with rhizobia and the flavonoids naringenin, isoliquiritigenin, and kaempferol, or with the synthetic auxin transport inhibitor 2,3,5,-triiodobenzoic acid, rescued nodulation efficiency in cre1 mutants and allowed auxin transport control in response to rhizobia. Our results suggest that CRE1-dependent cytokinin signaling leads to nodule initiation through the regulation of flavonoid accumulation required for local alteration of polar auxin transport and subsequent auxin accumulation in cortical cells during the early stages of nodulation.

  20. Auxin-dependent compositional change in Mediator in ARF7- and ARF19-mediated transcription.

    Science.gov (United States)

    Ito, Jun; Fukaki, Hidehiro; Onoda, Makoto; Li, Lin; Li, Chuanyou; Tasaka, Masao; Furutani, Masahiko

    2016-06-07

    Mediator is a multiprotein complex that integrates the signals from transcription factors binding to the promoter and transmits them to achieve gene transcription. The subunits of Mediator complex reside in four modules: the head, middle, tail, and dissociable CDK8 kinase module (CKM). The head, middle, and tail modules form the core Mediator complex, and the association of CKM can modify the function of Mediator in transcription. Here, we show genetic and biochemical evidence that CKM-associated Mediator transmits auxin-dependent transcriptional repression in lateral root (LR) formation. The AUXIN/INDOLE 3-ACETIC ACID 14 (Aux/IAA14) transcriptional repressor inhibits the transcriptional activity of its binding partners AUXIN RESPONSE FACTOR 7 (ARF7) and ARF19 by making a complex with the CKM-associated Mediator. In addition, TOPLESS (TPL), a transcriptional corepressor, forms a bridge between IAA14 and the CKM component MED13 through the physical interaction. ChIP assays show that auxin induces the dissociation of MED13 but not the tail module component MED25 from the ARF7 binding region upstream of its target gene. These findings indicate that auxin-induced degradation of IAA14 changes the module composition of Mediator interacting with ARF7 and ARF19 in the upstream region of their target genes involved in LR formation. We suggest that this regulation leads to a quick switch of signal transmission from ARFs to target gene expression in response to auxin.

  1. Auxin physiology of the tomato mutant diageotropica

    Science.gov (United States)

    Daniel, S. G.; Rayle, D. L.; Cleland, R. E.

    1989-01-01

    The tomato (Lycopersicon esculentum, Mill.) mutant diageotropica (dgt) exhibits biochemical, physiological, and morphological abnormalities that suggest the mutation may have affected a primary site of auxin perception or action. We have compared two aspects of the auxin physiology of dgt and wild-type (VFN8) seedlings: auxin transport and cellular growth parameters. The rates of basipetal indole-3-acetic acid (IAA) polar transport are identical in hypocotyl sections of the two genotypes, but dgt sections have a slightly greater capacity for IAA transport. 2,3,5-Triiodobenzoic acid and ethylene reduce transport in both mutant and wild-type sections. The kinetics of auxin uptake into VFN8 and dgt sections are nearly identical. These results make it unlikely that an altered IAA efflux carrier or IAA uptake symport are responsible for the pleiotropic effects resulting from the dgt mutation. The lack of auxin-induced cell elongation in dgt plants is not due to insufficient turgor, as the osmotic potential of dgt cell sap is less (more negative) than that of VFN8. An auxin-induced increase in wall extensibility, as measured by the Instron technique, only occurs in the VFN8 plants. These data suggest dgt hypocotyls suffer a defect in the sequence of events culminating in auxin-induced cell wall loosening.

  2. The promoting effects of alginate oligosaccharides on root development in Oryza sativa L. mediated by auxin signaling.

    Science.gov (United States)

    Zhang, Yunhong; Yin, Heng; Zhao, Xiaoming; Wang, Wenxia; Du, Yuguang; He, Ailing; Sun, Kegang

    2014-11-26

    Alginate oligosaccharides (AOS), which are marine oligosaccharides, are involved in regulating plant root growth, but the promotion mechanism for AOS remains unclear. Here, AOS (10-80 mg/L) induced the expression of auxin-related gene (OsYUCCA1, OsYUCCA5, OsIAA11 and OsPIN1) in rice (Oryza sativa L.) tissues to accelerate auxin biosynthesis and transport, and reduced indole-3-acetic acid (IAA) oxidase activity in rice roots. These changes resulted in the increase of 37.8% in IAA concentration in rice roots, thereby inducing the expression of root development-related genes, promoting root growth in a dose-dependent manner, which were inhibited by auxin transport inhibitor 2,3,5-triiodo benzoic acid (TIBA) and calcium-chelating agent ethylene glycol bis (2-aminoethyl) tetraacetic acid (EGTA). AOS also induced calcium signaling generation in rice roots. Those results indicated that auxin mediated AOS regulation of root development, and calcium signaling may act mainly in the upstream of auxin in the regulation of AOS on rice root development.

  3. Auxin response under osmotic stress.

    Science.gov (United States)

    Naser, Victoria; Shani, Eilon

    2016-08-01

    The phytohormone auxin (indole-3-acetic acid, IAA) is a small organic molecule that coordinates many of the key processes in plant development and adaptive growth. Plants regulate the auxin response pathways at multiple levels including biosynthesis, metabolism, transport and perception. One of the most striking aspects of plant plasticity is the modulation of development in response to changing growth environments. In this review, we explore recent findings correlating auxin response-dependent growth and development with osmotic stresses. Studies of water deficit, dehydration, salt, and other osmotic stresses point towards direct and indirect molecular perturbations in the auxin pathway. Osmotic stress stimuli modulate auxin responses by affecting auxin biosynthesis (YUC, TAA1), transport (PIN), perception (TIR/AFB, Aux/IAA), and inactivation/conjugation (GH3, miR167, IAR3) to coordinate growth and patterning. In turn, stress-modulated auxin gradients drive physiological and developmental mechanisms such as stomata aperture, aquaporin and lateral root positioning. We conclude by arguing that auxin-mediated growth inhibition under abiotic stress conditions is one of the developmental and physiological strategies to acclimate to the changing environment.

  4. Auxin and its transport play a role in plant tolerance to arsenite-induced oxidative stress in Arabidopsis thaliana.

    Science.gov (United States)

    Krishnamurthy, Aparna; Rathinasabapathi, Bala

    2013-10-01

    The role of auxin in plant development is well known; however, its possible function in root response to abiotic stress is poorly understood. In this study, we demonstrate a novel role of auxin transport in plant tolerance to oxidative stress caused by arsenite. Plant response to arsenite [As(III)] was evaluated by measuring root growth and markers for stress on seedlings treated with control or As(III)-containing medium. Auxin transporter mutants aux1, pin1 and pin2 were significantly more sensitive to As(III) than the wild type (WT). Auxin transport inhibitors significantly reduced plant tolerance to As(III) in the WT, while exogenous supply of indole-3-acetic acid improved As(III) tolerance of aux1 and not that of WT. Uptake assays using H(3) -IAA showed As(III) affected auxin transport in WT roots. As(III) increased the levels of H2 O2 in WT but not in aux1, suggesting a positive role for auxin transport through AUX1 on plant tolerance to As(III) stress via reactive oxygen species (ROS)-mediated signalling. Compared to the WT, the mutant aux1 was significantly more sensitive to high-temperature stress and salinity, also suggesting auxin transport influences a common element shared by plant tolerance to arsenite, salinity and high-temperature stress.

  5. The rice FISH BONE gene encodes a tryptophan aminotransferase, which affects pleiotropic auxin-related processes.

    Science.gov (United States)

    Yoshikawa, Takanori; Ito, Momoyo; Sumikura, Tsuyoshi; Nakayama, Akira; Nishimura, Takeshi; Kitano, Hidemi; Yamaguchi, Isomaro; Koshiba, Tomokazu; Hibara, Ken-Ichiro; Nagato, Yasuo; Itoh, Jun-Ichi

    2014-06-01

    Auxin is a fundamental plant hormone and its localization within organs plays pivotal roles in plant growth and development. Analysis of many Arabidopsis mutants that were defective in auxin biosynthesis revealed that the indole-3-pyruvic acid (IPA) pathway, catalyzed by the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA) and YUCCA (YUC) families, is the major biosynthetic pathway of indole-3-acetic acid (IAA). In contrast, little information is known about the molecular mechanisms of auxin biosynthesis in rice. In this study, we identified a auxin-related rice mutant, fish bone (fib). FIB encodes an orthologue of TAA genes and loss of FIB function resulted in pleiotropic abnormal phenotypes, such as small leaves with large lamina joint angles, abnormal vascular development, small panicles, abnormal organ identity and defects in root development, together with a reduction in internal IAA levels. Moreover, we found that auxin sensitivity and polar transport activity were altered in the fib mutant. From these results, we suggest that FIB plays a pivotal role in IAA biosynthesis in rice and that auxin biosynthesis, transport and sensitivity are closely interrelated.

  6. Small-molecule auxin inhibitors that target YUCCA are powerful tools for studying auxin function.

    Science.gov (United States)

    Kakei, Yusuke; Yamazaki, Chiaki; Suzuki, Masashi; Nakamura, Ayako; Sato, Akiko; Ishida, Yosuke; Kikuchi, Rie; Higashi, Shouichi; Kokudo, Yumiko; Ishii, Takahiro; Soeno, Kazuo; Shimada, Yukihisa

    2015-11-01

    Auxin is essential for plant growth and development, this makes it difficult to study the biological function of auxin using auxin-deficient mutants. Chemical genetics have the potential to overcome this difficulty by temporally reducing the auxin function using inhibitors. Recently, the indole-3-pyruvate (IPyA) pathway was suggested to be a major biosynthesis pathway in Arabidopsis thaliana L. for indole-3-acetic acid (IAA), the most common member of the auxin family. In this pathway, YUCCA, a flavin-containing monooxygenase (YUC), catalyzes the last step of conversion from IPyA to IAA. In this study, we screened effective inhibitors, 4-biphenylboronic acid (BBo) and 4-phenoxyphenylboronic acid (PPBo), which target YUC. These compounds inhibited the activity of recombinant YUC in vitro, reduced endogenous IAA content, and inhibited primary root elongation and lateral root formation in wild-type Arabidopsis seedlings. Co-treatment with IAA reduced the inhibitory effects. Kinetic studies of BBo and PPBo showed that they are competitive inhibitors of the substrate IPyA. Inhibition constants (Ki ) of BBo and PPBo were 67 and 56 nm, respectively. In addition, PPBo did not interfere with the auxin response of auxin-marker genes when it was co-treated with IAA, suggesting that PPBo is not an inhibitor of auxin sensing or signaling. We propose that these compounds are a class of auxin biosynthesis inhibitors that target YUC. These small molecules are powerful tools for the chemical genetic analysis of auxin function.

  7. Development of the Poplar-Laccaria bicolor Ectomycorrhiza Modifies Root Auxin Metabolism, Signaling, and Response.

    Science.gov (United States)

    Vayssières, Alice; Pěnčík, Ales; Felten, Judith; Kohler, Annegret; Ljung, Karin; Martin, Francis; Legué, Valérie

    2015-09-01

    Root systems of host trees are known to establish ectomycorrhizae (ECM) interactions with rhizospheric fungi. This mutualistic association leads to dramatic developmental modifications in root architecture, with the formation of numerous short and swollen lateral roots ensheathed by a fungal mantle. Knowing that auxin plays a crucial role in root development, we investigated how auxin metabolism, signaling, and response are affected in poplar (Populus spp.)-Laccaria bicolor ECM roots. The plant-fungus interaction leads to the arrest of lateral root growth with simultaneous attenuation of the synthetic auxin response element DR5. Measurement of auxin-related metabolites in the free-living partners revealed that the mycelium of L. bicolor produces high concentrations of the auxin indole-3-acetic acid (IAA). Metabolic profiling showed an accumulation of IAA and changes in the indol-3-pyruvic acid-dependent IAA biosynthesis and IAA conjugation and degradation pathways during ECM formation. The global analysis of auxin response gene expression and the regulation of AUXIN SIGNALING F-BOX PROTEIN5, AUXIN/IAA, and AUXIN RESPONSE FACTOR expression in ECM roots suggested that symbiosis-dependent auxin signaling is activated during the colonization by L. bicolor. Taking all this evidence into account, we propose a model in which auxin signaling plays a crucial role in the modification of root growth during ECM formation.

  8. Enhancement of lead uptake by alfalfa (Medicago sativa) using EDTA and a plant growth promoter.

    Science.gov (United States)

    López, Martha L; Peralta-Videa, Jose R; Benitez, Tenoch; Gardea-Torresdey, Jorge L

    2005-10-01

    Phytoremediation is a novel cleanup technology for the removal of contaminants from polluted waters and soils. In phytoremediation, the plant uptake capability and the availability of the pollutant in the media are important. Here we show the results of a study on the combined effects of ethylenediaminetetraacetic acid (EDTA) and the phytohormone indole-3-acetic acid (IAA) on Pb uptake by Medicago sativa (alfalfa). Plants were grown in hydroponics media containing a nutrient solution amended with Pb at 0.2mM and different combinations of EDTA, and IAA. After 10d of treatment, the Pb content in plant tissues was quantified using an Inductively Coupled Plasma Optical Emission Spectrometer (ICP/OES). The results showed that the combination of 100 microM IAA/0.2 mM EDTA increased the Pb accumulation in leaves by about 2800% and by about 600%, as compared to Pb content in leaves of plants exposed to Pb alone and those cultivated with Pb/EDTA, respectively. These results indicate that non-metal hyperaccumulator plants could increase their hyperaccumulating potential without genetic manipulation.

  9. Identification and Functional Analysis of microRNAs Involved in the Anther Development in Cotton Genic Male Sterile Line Yu98-8A

    Directory of Open Access Journals (Sweden)

    Xiaojie Yang

    2016-10-01

    Full Text Available Hybrid vigor contributes in a large way to the yield and quality of cotton (Gossypium hirsutum fiber. Although microRNAs play essential regulatory roles in flower induction and development, it is still unclear if microRNAs are involved in male sterility, as the regulatory molecular mechanisms of male sterility in cotton need to be better defined. In this study, two independent small RNA libraries were constructed and sequenced from the young buds collected from the sporogenous cell formation to the meiosis stage of the male sterile line Yu98-8A and the near-isogenic line. Sequencing revealed 1588 and 1536 known microRNAs and 347 and 351 novel miRNAs from male sterile and male fertile libraries, respectively. MicroRNA expression profiles revealed that 49 conserved and 51 novel miRNAs were differentially expressed. Bioinformatic and degradome analysis indicated the regulatory complexity of microRNAs during flower induction and development. Further RT-qPCR and physiological analysis indicated that, among the different Kyoto Encyclopedia Gene and Genomes pathways, indole-3-acetic acid and gibberellic acid signaling transduction pathways may play pivotal regulatory functions in male sterility.

  10. Modulation of auxin content in Arabidopsis confers improved drought stress resistance.

    Science.gov (United States)

    Shi, Haitao; Chen, Li; Ye, Tiantian; Liu, Xiaodong; Ding, Kejian; Chan, Zhulong

    2014-09-01

    Auxin is a well-known plant phytohormone that is involved in multiple plant growth processes and stress responses. In this study, auxin response was significantly modulated under drought stress condition. The iaaM-OX transgenic lines with higher endogenous indole-3-acetic acid (IAA) level and IAA pre-treated wild type (WT) plants exhibited enhanced drought stress resistance, while the yuc1yuc2yuc6 triple mutants with lower endogenous IAA level showed decreased stress resistance in comparison to non-treated WT plants. Additionally, endogenous and exogenous auxin positively modulated the expression levels of multiple abiotic stress-related genes (RAB18, RD22, RD29A, RD29B, DREB2A, and DREB2B), and positively affected reactive oxygen species (ROS) metabolism and underlying antioxidant enzyme activities. Moreover, auxin significantly modulated some carbon metabolites including amino acids, organic acids, sugars, sugar alcohols and aromatic amines. Notably, endogenous and exogenous auxin positively modulated root architecture especially the lateral root number. Taken together, this study demonstrated that auxin might participate in the positive regulation of drought stress resistance, through regulation of root architecture, ABA-responsive genes expression, ROS metabolism, and metabolic homeostasis, at least partially.

  11. Roles of YUCCAs in auxin biosynthesis and drought stress responses in plants.

    Science.gov (United States)

    Cheol Park, Hyeong; Cha, Joon-Yung; Yun, Dae-Jin

    2013-06-01

    Auxin, a plant hormone, plays crucial roles in diverse aspects of plant growth and development reacting to and integrating environmental stimuli. Indole-3-acetic acid (IAA) is the major plant auxin that is synthesized by members of the YUCCA (YUC) family of flavin monooxygenases that catalyse a rate-limiting step. Although the paths to IAA biosynthesis are characterized in Arabidopsis, little is known about the corresponding components in potato. Recently, we isolated eight putative StYUC (Solanum tuberosum YUCCA) genes and five putative tryptophan aminotransferase genes in comparison to those found in Arabidopsis. (1) The specific domains of YUC proteins were well conserved in all StYUC amino acid sequences. Transgenic potato (Solanum tuberosum cv. Jowon) overexpressing AtYUC6 showed high-auxin and enhanced drought tolerance phenotypes. The transgenic potatoes also exhibited reduced levels of ROS (reactive oxygen species) compared to control plants. We therefore propose that YUCCA and TAA families in potato would function in the auxin biosynthesis. The overexpression of AtYUC6 in potato establishes enhanced drought tolerance through regulated ROS homeostasis.

  12. Evaluation of element migration from food plastic packagings into simulated solutions using radiometric method; Avaliacao da migracao de elementos de embalagens plasticas de alimentos para solucoes simulantes pelo metodo radiometrico

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Eufemia Paez [Escola SENAI ' Fundacao Zerrenner' , Sao Paulo, SP (Brazil)]. E-mail: vlcastro@dialdata.com.br; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: mitiko@ipen.br; Wiebeck, Helio [Sao Paulo Univ., SP (Brazil). Escola Politecnica]. E-mail: hwiebeck@usp.br

    2005-07-01

    In the present study a radiometric method was established to determine the migration of elements from food plastic packagings to a simulated acetic acid solution. This radiometric method consisted of irradiating plastic samples with neutrons at IEA-R1 nuclear reactor for a period of 16 hours under a neutron flux of 10{sup 12} n cm{sup -2} s{sup -1} and, then to expose them to the element migration into a simulated solution. The radioactivity of the activated elements transferred to the solutions was measured to evaluate the migration. The experimental conditions were: time of exposure of 10 days at 40 deg C and 3% acetic acid solution was used as simulated solution, according to the procedure established by the National Agency of Sanitary Monitoring (ANVISA). The migration study was applied for plastic samples from soft drink and juice packagings. The results obtained indicated the migration of elements Co, Cr and Sb. The advantage of this methodology was no need to analyse the blank of simulantes, as well as the use of high purity simulated solutions. Besides, the method allows to evaluate the migration of the elements into the food content instead of simulated solution. The detention limits indicated high sensitivity of the radiometric method. (author)

  13. RpoS differentially affects the general stress response and biofilm formation in the endophytic Serratia plymuthica G3.

    Science.gov (United States)

    Liu, Xiaoguang; Wu, Yan; Chen, Yuanyuan; Xu, Fang; Halliday, Nigel; Gao, Kexiang; Chan, Kok Gan; Cámara, Miguel

    2016-04-01

    The σ(S) subunit RpoS of RNA polymerase functions as a master regulator of the general stress response in Escherichia coli and related bacteria. RpoS has been reported to modulate biocontrol properties in the rhizobacterium Serratia plymuthica IC1270. However, the role of RpoS in the stress response and biofilm formation in S. plymuthica remains largely unknown. Here we studied the role of RpoS from an endophytic S. plymuthica G3 in regulating these phenotypes. Mutational analysis demonstrated that RpoS positively regulates the global stress response to acid or alkaline stresses, oxidative stress, hyperosmolarity, heat shock and carbon starvation, in addition to proteolytic and chitinolytic activities. Interestingly, rpoS mutations resulted in significantly enhanced swimming motility, biofilm formation and production of the plant auxin indole-3-acetic acid (IAA), which may contribute to competitive colonization and environmental fitness for survival. These findings provide further insight into the strain-specific role of RpoS in the endophytic strain G3 of S. plymuthica, where it confers resistance to general stresses encountered within the plant environment. The heterogeneous functionality of RpoS in rhizosphere and endophytic S. plymuthica populations may provide a selective advantage for better adaptation to various physiological and environmental stresses.

  14. Isolation of Endophytic Plant Growth-Promoting Bacteria Associated with the Halophyte Salicornia europaea and Evaluation of their Promoting Activity Under Salt Stress.

    Science.gov (United States)

    Zhao, Shuai; Zhou, Na; Zhao, Zheng-Yong; Zhang, Ke; Wu, Guo-Hua; Tian, Chang-Yan

    2016-10-01

    Several reports have highlighted that many plant growth-promoting endophytic bacteria (PGPE) can assist their host plants in coping with various biotic and abiotic stresses. However, information about the PGPE colonizing in the halophytes is still scarce. This study was designed to isolate and characterize PGPE from salt-accumulating halophyte Salicornia europaea grown under extreme salinity and to evaluate in vitro the bacterial mechanisms related to plant growth promotion. A total of 105 isolates were obtained from the surface-sterilized roots, stems, and assimilation twigs of S. europaea. Thirty-two isolates were initially selected for their ability to produce 1-aminocyclopropane-1-carboxylate deaminase as well as other properties such as production of indole-3-acetic acid and phosphate-solubilizing activities. The 16S rRNA gene-sequencing analysis revealed that these isolates belong to 13 different genera and 19 bacterial species. For these 32 strains, seed germination and seedling growth in axenically grown S. europaea seedlings at different NaCl concentrations (50-500 mM) were quantified. Five isolates possessing significant stimulation of the host plant growth were obtained. The five isolates were identified as Bacillus endophyticus, Bacillus tequilensis, Planococcus rifietoensis, Variovorax paradoxus, and Arthrobacter agilis. All the five strains could colonize and can be reisolated from the host plant interior tissues. These results demonstrate that habitat-adapted PGPE isolated from halophyte could enhance plant growth under saline stress conditions.

  15. Extracellular ATP inhibits root gravitropism at concentrations that inhibit polar auxin transport

    Science.gov (United States)

    Tang, Wenqiang; Brady, Shari R.; Sun, Yu; Muday, Gloria K.; Roux, Stanley J.

    2003-01-01

    Raising the level of extracellular ATP to mM concentrations similar to those found inside cells can block gravitropism of Arabidopsis roots. When plants are grown in Murashige and Skoog medium supplied with 1 mM ATP, their roots grow horizontally instead of growing straight down. Medium with 2 mM ATP induces root curling, and 3 mM ATP stimulates lateral root growth. When plants are transferred to medium containing exogenous ATP, the gravity response is reduced or in some cases completely blocked by ATP. Equivalent concentrations of ADP or inorganic phosphate have slight but usually statistically insignificant effects, suggesting the specificity of ATP in these responses. The ATP effects may be attributable to the disturbance of auxin distribution in roots by exogenously applied ATP, because extracellular ATP can alter the pattern of auxin-induced gene expression in DR5-beta-glucuronidase transgenic plants and increase the response sensitivity of plant roots to exogenously added auxin. The presence of extracellular ATP also decreases basipetal auxin transport in a dose-dependent fashion in both maize (Zea mays) and Arabidopsis roots and increases the retention of [(3)H]indole-3-acetic acid in root tips of maize. Taken together, these results suggest that the inhibitory effects of extracellular ATP on auxin distribution may happen at the level of auxin export. The potential role of the trans-plasma membrane ATP gradient in auxin export and plant root gravitropism is discussed.

  16. Zinc Acetate Immobilized on Mesoporous Materials by Acetate Ionic Liquids as Catalysts for Vinyl Acetate Synthesis

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    Hang Xu

    2015-01-01

    Full Text Available Ionic liquid containing active ingredient Zn(CH3COO2 was loaded in mesoporous silica gel to form supported ionic liquids catalyst (SILC which was used to synthesize vinyl acetate monomer (VAM. SILC was characterized by 1HNMR, FT-IR, TGA, BET, and N2 adsorption/desorption and the acetylene method was used to evaluate SILC catalytic activity and stability in fixed reactor. The result shows that 1-allyl-3-acetic ether imidazole acetate ionic liquid is successfully fixed within mesoporous channel of silica gel. The average thickness of ionic liquid catalyst layer is about 1.05 nm. When the catalytic temperature is 195°C, the acetic acid (HAc conversion is 10.9% with 1.1 g vinyl acetate yield and 98% vinyl acetate (VAc selectivity. The HAc conversion is increased by rise of catalytic temperature and molar ratio of C2H2 : HAc and decreased by mass space velocity (WHSV. The catalyst activity is not significantly reduced within 7 days and VAc selectivity has a slight decrease.

  17. STUDIES ON THE MAJOR FACTORS AFFECTING IN VITRO MICROPROPAGATION OF TWO INTERGENERIC HYBRIDS FRAGARIA × POTENTILLA

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    Anca Nicoleta Şuțan

    2012-04-01

    Full Text Available In order to establish the major factors affecting in vitro micropropagation of intergeneric hybrids Fragaria × Potentilla, respectively ‘Pink Panda’ and ‘Serenata’, basic culture media Murashige-Skoog (MS, Lee-Fossard (LF and Knop, were supplemented with 6-benzylaminopurine (BAP, kinetine (Kin, indole-3-acetic acid (AIA, indole-3-butyric acid (AIB and gibberellic acid (GA3, in different combination and concentration. In ornamental strawberry ‘Serenata’, which showed a genetic potential of shoot regeneration significantly higher compared with ‘Pink Panda’, a high multiplication rate associated with a high vigor of shoots was obtained on MS medium supplemented with 0.5 mg/l BAP + 0.1 mg/l AIB + 0.1 mg/l GA3. The same combination of growth regulators, added in MS medium in higher concentrations, namely 1.0 mg/l BAP + 0.2 mg/l AIB + 0.1 mg/l GA3 led to the highest rate of multiplication in ‘Pink Panda’ intergeneric hybrid of Fragaria × Potentilla.

  18. Soluble species in aerosols collected on the route of the Second Chinese National Arctic Research Expedition

    Institute of Scientific and Technical Information of China (English)

    Xu Jianzhong; Sun Junying; Ren Jiawen; Qin Dahe

    2005-01-01

    Aerosol samples are collected on the route of the Second Chinese National Arctic Research Expedition from July 15 to September 28, 2003. The concentration of water soluble ions (Na+, NH4+, Ca2+, CI-, MSA , SO42- and so on) are analyzed. By correlation analysis, the ions can be divided into three groups: ( 1 ) Na + ,Mg2+ , K + , Ca2 + , Cl- , SO42 - , mainly from sea salt; (2) NH4+ , NO3- , markedly from coastal regions of the continents ; (3) Acetate, MSA, C2042-, from other sources. Marine aerosols are the dominant origin, Cl- and Na + are the most dominant anion and cation, respectively and these two ions ( Na + + Cl - ) account for 55.6% of the total aerosol loading. The mean equivalence ratio of NH4+/SO42 - is 0.45,we suggest that ammonium and sulfate exist mainly as NH4HSO4. The concentration of NO3- shows three different patterns on the route of expedition: Japan Sea with meparison of the concentration of main water soluble ions between the First and Second Chinese National Arctic Research Expedition, the variation matches each other.

  19. Rhodanineacetic Acid Derivatives as Potential Drugs: Preparation, Hydrophobic Properties and Antifungal Activity of (5-Arylalkylidene-4-oxo-2-thioxo-1,3-thiazolidin-3-ylacetic Acids

    Directory of Open Access Journals (Sweden)

    Josef Jampilek

    2009-10-01

    Full Text Available Some [(5Z-(5-arylalkylidene-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acids were prepared as potential antifungal compounds. The general synthetic approach to all synthesized compounds is presented. Lipophilicity of all the discussed rhodanine-3-acetic acid derivatives was analyzed using a reversed phase high performance liquid chromatography (RP-HPLC method. The procedure was performed under isocratic conditions with methanol as an organic modifier in the mobile phase using an end-capped non-polar C18 stationary RP column. The RP-HPLC retention parameter log k (the logarithm of the capacity factor k is compared with log P values calculated in silico. All compounds were evaluated for antifungal effects against selected fungal species. Most compounds exhibited no interesting activity, and only {(5Z-[4-oxo-5-(pyridin-2- ylmethylidene-2-thioxo-1,3-thiazolidin-3-yl]}acetic acid strongly inhibited the growth of Candida tropicalis 156, Candida krusei E 28, Candida glabrata 20/I and Trichosporon asahii 1188.

  20. Auxin biosynthesis by the YUCCA6 flavin monooxygenase gene in woodland strawberry.

    Science.gov (United States)

    Liu, Hong; Xie, Wei-Fa; Zhang, Ling; Valpuesta, Victoriano; Ye, Zheng-Wen; Gao, Qing-Hua; Duan, Ke

    2014-04-01

    Auxin has been regarded as the main signal molecule coordinating the growth and ripening of fruits in strawberry, the reference genomic system for Rosaceae. The mechanisms regulating auxin biosynthesis in strawberry are largely elusive. Recently, we demonstrated that two YUCCA genes are involved in flower and fruit development in cultivated strawberry. Here, we show that the woodland strawberry (Fragaria vesca L.) genome harbors nine loci for YUCCA genes and eight of them encode functional proteins. Transcription pattern in different plant organs was different for all eight FvYUCs. Functionality of the FvYUC6 gene was studied in transgenic strawberry overexpressing FvYUC6, which showed typical high-auxin phenotypes. Overexpression of FvYUC6 also delayed flowering and led to complete male sterility in F. vesca. Additionally, specific repression of FvYUC6 expression by RNA interference significantly inhibited vegetative growth and reduced plant fertility. The development of leaves, roots, flowers, and fruits was greatly affected in FvYUC6-repressed plants. Expression of a subset of auxin-responsive genes was well correlated with the changes of FvYUC6 transcript levels and free indole-3-acetic acid levels in transgenic strawberry. These observations are consistent with an important role of FvYUC6 in auxin synthesis, and support a main role of the gene product in vegetative and reproductive development in woodland strawberry.

  1. MASSUGU2 encodes Aux/IAA19, an auxin-regulated protein that functions together with the transcriptional activator NPH4/ARF7 to regulate differential growth responses of hypocotyl and formation of lateral roots in Arabidopsis thaliana.

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    Tatematsu, Kiyoshi; Kumagai, Satoshi; Muto, Hideki; Sato, Atsuko; Watahiki, Masaaki K; Harper, Reneé M; Liscum, Emmanuel; Yamamoto, Kotaro T

    2004-02-01

    We have isolated a dominant, auxin-insensitive mutant of Arabidopsis thaliana, massugu2 (msg2), that displays neither hypocotyl gravitropism nor phototropism, fails to maintain an apical hook as an etiolated seedling, and is defective in lateral root formation. Yet other aspects of growth and development of msg2 plants are almost normal. These characteristics of msg2 are similar to those of another auxin-insensitive mutant, non-phototropic hypocotyl4 (nph4), which is a loss-of-function mutant of AUXIN RESPONSE FACTOR7 (ARF7) (Harper et al., 2000). Map-based cloning of the MSG2 locus reveals that all four mutant alleles result in amino acid substitutions in the conserved domain II of an Auxin/Indole-3-Acetic Acid protein, IAA19. Interestingly, auxin inducibility of MSG2/IAA19 gene expression is reduced by 65% in nph4/arf7. Moreover, MSG2/IAA19 protein binds to the C-terminal domain of NPH4/ARF7 in a Saccharomyces cerevisiae (yeast) two-hybrid assay and to the whole latter protein in vitro by pull-down assay. These results suggest that MSG2/IAA19 and NPH4/ARF7 may constitute a negative feedback loop to regulate differential growth responses of hypocotyls and lateral root formation.

  2. Brassinosteroids stimulate plant tropisms through modulation of polar auxin transport in Brassica and Arabidopsis.

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    Li, Li; Xu, Jian; Xu, Zhi-Hong; Xue, Hong-Wei

    2005-10-01

    Brassinosteroids (BRs) are important plant growth regulators in multiple developmental processes. Previous studies have indicated that BR treatment enhanced auxin-related responses, but the underlying mechanisms remain unknown. Using (14)C-labeled indole-3-acetic acid and Arabidopsis thaliana plants harboring an auxin-responsive reporter construct, we show that the BR brassinolide (BL) stimulates polar auxin transport capacities and modifies the distribution of endogenous auxin. In plants treated with BL or defective in BR biosynthesis or signaling, the transcription of PIN genes, which facilitate functional auxin transport in plants, was differentially regulated. In addition, BL enhanced plant tropistic responses by promoting the accumulation of the PIN2 protein from the root tip to the elongation zone and stimulating the expression and dispersed localization of ROP2 during tropistic responses. Constitutive overexpression of ROP2 results in enhanced polar accumulation of PIN2 protein in the root elongation region and increased gravitropism, which is significantly affected by latrunculin B, an inhibitor of F-actin assembly. The ROP2 dominant negative mutants (35S-ROP2-DA/DN) show delayed tropistic responses, and this delay cannot be reversed by BL addition, strongly supporting the idea that ROP2 modulates the functional localization of PIN2 through regulation of the assembly/reassembly of F-actins, thereby mediating the BR effects on polar auxin transport and tropistic responses.

  3. The transparent testa4 mutation prevents flavonoid synthesis and alters auxin transport and the response of Arabidopsis roots to gravity and light.

    Science.gov (United States)

    Buer, Charles S; Muday, Gloria K

    2004-05-01

    We examined whether flavonoids act as endogenous auxin transport regulators during gravity vector and light intensity changes in Arabidopsis thaliana roots. Flavonoid deficient transparent testa4 [tt4(2YY6)] seedlings had elevated root basipetal auxin transport compared with the wild type, consistent with the absence of a negative auxin transport regulator. The tt4(2YY6) roots had delayed gravitropism that was chemically complemented with a flavonoid intermediate. Flavonoid accumulation was found in wild-type columella cells, the site of gravity perception, and in epidermal and cortical cells, the site of differential growth, but flavonoid accumulation was absent in tt4(2YY6) roots. Flavonoid accumulation was higher in gravity-stimulated root tips as compared with vertical controls, with maximum differences coinciding with the timing of gravitropic bending, and was located in epidermal cells. Exogenous indole-3-acetic acid (IAA) also elevated flavonoid accumulation, suggesting that flavonoid changes in response to gravity might be partly as a result of changing IAA distribution. Acropetal IAA transport was also elevated in roots of tt4(2YY6). Flavonoid synthesis was repressed in the dark, as were differences in root acropetal transport in tt4(2YY6). These results are consistent with light- and gravity-induced flavonoid stimulation that alters auxin transport in roots and dependent physiological processes, including gravitropic bending and root development.

  4. Kudsuphilactone B, a nortriterpenoid isolated from Schisandra chinensis fruit, induces caspase-dependent apoptosis in human ovarian cancer A2780 cells.

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    Jeong, Miran; Kim, Hye Mi; Kim, Hyun Ji; Choi, Jung-Hye; Jang, Dae Sik

    2017-02-22

    A phytochemical study on the fruits of Schisandra chinensis led to the isolation and characterization of nineteen compounds. The structures of the isolates were determined to be schizandrin, deoxyschizandrin, angeloylgomisin H, gomisin A, gomisin J, (-)-gomisin L1, (-)-gomisin L2, wuweizisu C, gomisin N, meso-dihydroguaiaretic acid, kadsuphilactone B, α-ylangenol, α-ylangenyl acetate, β-chamigrenal, β-chamigrenic acid, 4-hydroxybenzoic acid, protocatechuic acid, p-methylcarvacrol, and indole-3-acetic acid. Of these, some lignans and a nortriterpene showed cytotoxic activity in human ovarian and endometrial cancer cells. In particular, a nortriterpenoid kadsuphilactone B exhibited significant cytotoxic activity with IC50 values below 25 μM in both A2780 and Ishikawa cells. Kadsuphilactone B induced apoptotic cell death and stimulated the activation of caspase-3, -8, and -9 and the cleavages of poly (ADP-ribose) polymerase. Caspase inhibitors attenuated the pro-apoptotic activity of kudsuphilactone B. In addition, kadsuphilactone B altered the expression levels of B cell lymphoma 2 (Bcl-2) family proteins. Moreover, activation of MAPKs was modulated by kadsuphilactone B in a dose-dependent manner. Taken together, these results show that kadsuphilactone B induces caspase-dependent apoptosis in human cancer cells via the regulation of Bcl-2 family protein and MAPK signaling.

  5. Screening of Azotobacter isolates for PGP properties and antifungal activity

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    Bjelić Dragana Đ.

    2015-01-01

    Full Text Available Аmong 50 bacterial isolates obtained from maize rhizospherе, 13 isolates belonged to the genus Azotobacter. Isolates were biochemically characterized and estimated for pH and halo tolerance ability and antibiotic resistance. According to characterization, the six representative isolates were selected and further screened in vitro for plant growth promoting properties: production of indole-3-acetic acid (IAA, siderophores, hydrogen cyanide (HCN, exopolysaccharides, phosphate solubilization and antifungal activity (vs. Helminthosporium sp., Macrophomina sp., Fusarium sp.. Beside HCN production, PGP properties were detected for all isolates except Azt7. All isolates produced IAA in the medium without L-tryptophan and the amount of produced IAA increased with concentration of precursor in medium. The highest amount of IAA was produced by isolates Azt4 (37.69 and 45.86 μg ml-1 and Azt5 (29.44 and 50.38 μg ml-1 in the medium with addition of L-tryptophan (2.5 and 5 mM. The isolates showed the highest antifungal activity against Helminthosporium sp. and the smallest antagonistic effect on Macrophomina sp. Radial Growth Inhibition (RGI obtained by the confrontation of isolates with tested phytopathogenic fungi, ranged from 10 to 48%. [Projekat Ministarstva nauke Republike Srbije, br. TR 31073

  6. Mycorrhiza alters the profile of root hairs in trifoliate orange.

    Science.gov (United States)

    Wu, Qiang-Sheng; Liu, Chun-Yan; Zhang, De-Jian; Zou, Ying-Ning; He, Xin-Hua; Wu, Qing-Hua

    2016-04-01

    Root hairs and arbuscular mycorrhiza (AM) coexist in root systems for nutrient and water absorption, but the relation between AM and root hairs is poorly known. A pot study was performed to evaluate the effects of four different AM fungi (AMF), namely, Claroideoglomus etunicatum, Diversispora versiformis, Funneliformis mosseae, and Rhizophagus intraradices on root hair development in trifoliate orange (Poncirus trifoliata) seedlings grown in sand. Mycorrhizal seedlings showed significantly higher root hair density than non-mycorrhizal seedlings, irrespective of AMF species. AMF inoculation generally significantly decreased root hair length in the first- and second-order lateral roots but increased it in the third- and fourth-order lateral roots. AMF colonization induced diverse responses in root hair diameter of different order lateral roots. Considerably greater concentrations of phosphorus (P), nitric oxide (NO), glucose, sucrose, indole-3-acetic acid (IAA), and methyl jasmonate (MeJA) were found in roots of AM seedlings than in non-AM seedlings. Levels of P, NO, carbohydrates, IAA, and MeJA in roots were correlated with AM formation and root hair development. These results suggest that AMF could alter the profile of root hairs in trifoliate orange through modulation of physiological activities. F. mosseae, which had the greatest positive effects, could represent an efficient AM fungus for increasing fruit yields or decreasing fertilizer inputs in citrus production.

  7. Arbuscular mycorrhizal symbiosis and methyl jasmonate avoid the inhibition of root hydraulic conductivity caused by drought.

    Science.gov (United States)

    Sánchez-Romera, Beatriz; Ruiz-Lozano, Juan Manuel; Zamarreño, Ángel María; García-Mina, José María; Aroca, Ricardo

    2016-02-01

    Hormonal regulation and symbiotic relationships provide benefits for plants to overcome stress conditions. The aim of this study was to elucidate the effects of exogenous methyl jasmonate (MeJA) application on root hydraulic conductivity (L) of Phaseolus vulgaris plants which established arbuscular mycorrhizal (AM) symbiosis under two water regimes (well-watered and drought conditions). The variation in endogenous contents of several hormones (MeJA, JA, abscisic acid (ABA), indol-3-acetic acid (IAA), salicylic acid (SA)) and the changes in aquaporin gene expression, protein abundance and phosphorylation state were analyzed. AM symbiosis decreased L under well-watered conditions, which was partially reverted by the MeJA treatment, apparently by a drop in root IAA contents. Also, AM symbiosis and MeJA prevented inhibition of L under drought conditions, most probably by a reduction in root SA contents. Additionally, the gene expression of two fungal aquaporins was upregulated under drought conditions, independently of the MeJA treatment. Plant aquaporin gene expression could not explain the behaviour of L. Conversely, evidence was found for the control of L by phosphorylation of aquaporins. Hence, MeJA addition modified the response of L to both AM symbiosis and drought, presumably by regulating the root contents of IAA and SA and the phosphorylation state of aquaporins.

  8. USE OF AGRICULTURAL WASTES FOR BIOMASS PRODUCTION OF THE PLANT GROWTH PROMOTER ACTINOBACTERIA, Streptomyces sp. MCR26

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    Iván Ávila-Cortes

    2014-10-01

    Full Text Available The use of agricultural wastes for plant growth promoting rhizobacteria (PGPR biomass production has not been widely explored. This study focuses on the development a culture medium for PGPR Streptomyces sp. MCR26, evaluating the influence of carnation harvest waste, yeast extract and ammonium sulfate on biomass production, as well as, the effect of biomass produced in the designed culture medium on the maintenance of PGPR MCR26 traits. The experiments were conducted by a full factorial design, varying nutritional sources concentrations, with duplicate experiments at the central point. Yeast extract and carnation harvest waste were the most influential factors, showing a positive effect on biomass production. The statistical model predicted optimal conditions for maximal biomass production at 20.0 g/L carnation harvest waste and 4.0 g/L yeast extract. Shake flask validation experiments resulted in 8.087 g/L of MCR26 biomass, 80.6% higher compared to carboxymetil cellulose (CMC broth. MCR26 biomass produced on designed culture medium enhanced hydroxamate production, and maintained phosphatases and indole-3-acetic acid synthesis. In addition, white clover inoculated plants presented higher shoot biomass accumulation compared to control treatment; nevertheless, there were no effects on seed germination. These results demonstrated that the designed culture medium effectively induced Streptomyces sp. MCR26 biomass production and maintained its plant growth promotion traits.

  9. Colonization strategy of the endophytic plant growth-promoting strains of Pseudomonas fluorescens and Klebsiella oxytoca on the seeds, seedlings and roots of the epiphytic orchid, Dendrobium nobile Lindl.

    Science.gov (United States)

    Pavlova, A S; Leontieva, M R; Smirnova, T A; Kolomeitseva, G L; Netrusov, A I; Tsavkelova, E A

    2017-04-29

    Orchids form strong mycorrhizal associations, but their interactions with bacteria are poorly understood. We aimed to investigate the distribution of plant growth promoting rhizobacteria (PGPR) at different stages of orchid development and to study if there is any selective specificity in choosing PGPR partners. Colonization patterns of gfp-tagged Pseudomonas fluorescens and Klebsiella oxytoca were studied on roots, seeds, and seedlings of Dendrobium nobile. Endophytic rhizobacteria rapidly colonized velamen and core parenchyma entering through exodermis and the passage cells, whereas at the early stages, they stayed restricted to the surface and the outer layers of the protocorms and rhizoids. The highest amounts of auxin (indole-3-acetic acid) were produced by K. oxytoca and P. fluorescens in the nitrogen-limiting and NO3 -containing media respectively. Bacterization of D. nobile seeds resulted in promotion of their in vitro germination. The plant showed no selective specificity to the tested strains. Klebsiella oxytoca demonstrated more intense colonization activity and more efficient growth promoting impact under tryptophan supplementation, while P. fluorescens revealed its growth-promoting capacity without tryptophan. Both strategies are regarded as complementary, improving adaptive potentials of the orchid when different microbial populations colonize the plant. This study enlarges our knowledge on orchid-microbial interactions, and provides new features on application of the nonorchid PGPR in orchid seed germination and conservation. © 2017 The Society for Applied Microbiology.

  10. Analyses of Phytohormones in Coconut (Cocos Nucifera L. Water Using Capillary Electrophoresis-Tandem Mass Spectrometry

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    Swee Ngin Tan

    2014-12-01

    Full Text Available Capillary electrophoresis (CE coupled with mass spectrometry (MS or tandem mass spectrometry (MS/MS is reported as an alternative and potentially useful method for the simultaneous analysis of various classes of phytohormones with diversified structures, including indole-3-acetic acid (IAA, indole-3-butyric acid (IBA, abscisic acid (ABA, gibberellic acid (GA, zeatin (Z, N6-benzyladenine (BA, α-naphthaleneacetic acid (NAA and 2,4-dichlorophenoxyacetic acid (2,4-D. The key to the CE-MS/MS analysis was based on electroosmotic flow reversal using a cationic polymer-coated capillary. Under optimum conditions, a baseline separation of eight phytohormones was accomplished within 30 min using 60 mM ammonium formate/formic acid buffer of pH 3.8 with −20 kV as the separation voltage. The accessibility of MS/MS together with the characterization by migration properties obtained by CE allows for the development of CE-MS/MS as an emerging potential method for the analysis of different classes of phytohormones in a single run. The utility of the CE-MS/MS method was demonstrated by the comprehensive screening of phytohormones in coconut (Cocos nucifera L. water after pre-concentration and purification through solid-phase extraction (SPE cartridge. IAA, ABA, GA and Z were detected and quantified in the purified coconut water extract sample.

  11. The Relationship between Polyamines and Hormones in the Regulation of Wheat Grain Filling

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    Liu, Yang; Gu, Dandan; Wu, Wei; Wen, Xiaoxia; Liao, Yuncheng

    2013-01-01

    The grain weight of wheat is strongly influenced by filling. Polyamines (PA) are involved in regulating plant growth. However, the effects of PA on wheat grain filling and its mechanism of action are unclear. The objective of the present study was to investigate the relationship between PAs and hormones in the regulation of wheat grain filling. Three PAs, spermidine (Spd), spermine (Spm), and putrescine (Put), were exogenously applied, and the grain filling characteristics and changes in endogenous PA and hormones, i.e., indole-3-acetic acid (IAA), zeatin (Z) + zeatin riboside (ZR), abscisic acid (ABA), ethylene (ETH) and gibberellin 1+4 (GAs), were quantified during wheat grain filling. Exogenous applications of Spd and Spm significantly increased the grain filling rate and weight, but exogenous Put had no significant effects on these measures. Exogenous Spd and Spm significantly increased the endogenous Spd, Spm, Z+ZR, ABA, and IAA contents and significantly decreased ETH evolution in grains. The endogenous Spd, Spm and Z+ZR contents were positively and significantly correlated with the grain filling rate and weight of wheat, and the endogenous ETH evolution was negatively and significantly correlated with the wheat grain filling rate and weight. Based upon these results, we concluded that PAs were involved in the balance of hormones that regulated the grain filling of wheat. PMID:24205154

  12. Gene expression and proteomic analysis of shoot apical meristem transition from dormancy to activation in Cunninghamia lanceolata (Lamb.) Hook.

    Science.gov (United States)

    Xu, Huimin; Cao, Dechang; Chen, Yanmei; Wei, Dongmei; Wang, Yanwei; Stevenson, Rebecca Ann; Zhu, Yingfang; Lin, Jinxing

    2016-02-02

    In contrast to annual plants, in perennial plants, the shoot apical meristem (SAM) can undergo seasonal transitions between dormancy and activity; understanding this transition is crucial for understanding growth in perennial plants. However, little is known about the molecular mechanisms of SAM development in trees. Here, light and transmission electron microscopy revealed that evident changes in starch granules, lipid bodies, and cell walls thickness of the SAM in C. lanceolata during the transition from dormancy to activation. HPLC-ESI-MS/MS analysis showed that levels of indole-3-acetic acid (IAA) increased and levels of abscisic acid (ABA) decreased from dormant to active stage. Examination of 20 genes and 132 differentially expressed proteins revealed that the expression of genes and proteins potentially involved in cell division and expansion significantly increased in the active stage, whereas those related to the abscisic acid insensitive 3(ABI3), the cytoskeleton and energy metabolism decreased in the dormant stage. These findings provide new insights into the complex mechanism of gene and protein expression and their relation to cytological and physiological changes of SAM in this coniferous species.

  13. The Analgesic Effect of Pineapple Fruit Juice on Mice

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    Ainul Atiqah binti Hilmi

    2014-08-01

    Full Text Available Background: Pain is a feeling stimulated by the nervous system which can be suppressed by giving an analgesic agent. Some studies revealed that pineapples have an analgesic effect. This study aim was to determine analgesic effect of pineapple on mice. Methods: In this experimental study, the effect was examined by using a writhing method on the 28 male mice. Subjects were divided into 4 groups with 7 mice each. The control group received aquades and other groups received pineapple fruit juice with 20%, 40% and 80% concentration with the dosage of 10 mL/kg/body weight. After 30 minutes, 3% acetic acid was injected intraperitoneally to induce pain. Writhing responseswere observed every 5 minutes for 30 minutes. Results: The result for mean of total writhing reaction was 2.39±0.40, 1.92±0.40, 1.50±2.13, 1.66±0.11 respectively for group 1 to 4. These data indicated a significant decrease of total writhing response in mice with 20%, 40% and 80% concentration compared to control group (p=0.023;p=0.000 and p=0.000 respectively. Most optimal concentration was40% with the protective percentage equal to 71.8%. Conclusion: Pineapple fruit juice concentrations (20%, 40%, and 80%has an analgesic effect with the most optimal concentration of 40%.

  14. Effects of IAA and IBA on the in vitro rooting of stem cuttings of Sechium edule (Jacq. Sw

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    José García García

    2015-01-01

    Full Text Available This investigation was carried out with the objective of evaluating the response of shoots of chayote [S. edule (Jacq. Sw.] to the application of indole-3-butyric acid (IBA and indole-3-acetic acid (IAA on the in vitro rooting phase. The effect of three culture media, modified from the proposed of Murashige and Skoog (MS was studied: 1- 65% MS salt base, 2- 65% MS salt base + 0.05 mg l-1 of indolebutyric acid (AIB and 3- 65% MS salt base + 3.0 mg l-1-3-indole acetic acid (IAA. The variables evaluated were: number of roots, length and number of shoots per in vitro seedling. The best result were obtained when using 65% MS salt base with 3.0 mg l-1 of IAA. Significant differences (P<0.05 among treatments containing growth regulators was obtained for the variables number of roots and length of in vitro plantlets. In the UNA-730 accession root induction was obtained in a 65% MS salt base culture medium without growth regulators; however, when IAA and IBA was added the induction was 100%. The differences identified in this work with regards to the root induction were probably the combined result of genotype and specific culture conditions. Key words: auxins, chayote, growth regulators, in vitro culture

  15. Water stress, CO2 and photoperiod influence hormone levels in wheat

    Science.gov (United States)

    Nan, Rubin; Carman, John G.; Salisbury, Frank B.; Campbell, W. F. (Principal Investigator)

    2002-01-01

    'Super Dwarf' wheat (Triticum aestivum L.) plants have been grown from seed to maturity in the Mir space station where they were periodically exposed, because of microgravity and other constraints, to water deficit, waterlogging, high CO2 levels, and low light intensities. The plants produced many tillers, but none of them produced viable seed. Studies have been initiated to determine why the plants responded in these ways. In the present study, effects of the listed stresses on abscisic acid (ABA), indole-3-acetic acid (IAA) and isopentenyl adenosine ([9R]iP) levels in roots and leaves of plants grown under otherwise near optimal conditions on earth were measured. Hormones were extracted, purified by HPLC, and quantified by noncompetitive indirect ELISA. In response to water deficit, ABA levels increased in roots and leaves, IAA levels decreased in roots and leaves, and [9R]iP levels increased in leaves but decreased in roots. In response to waterlogging, ABA, IAA and [9R]iP levels briefly increased in roots and leaves and then decreased. When portions of the root system were exposed to waterlogging and/or water deficit, ABA levels in leaves increased while [9R]iP and IAA levels decreased. These responses were correlated with the percentage of the root system stressed. At a low photosynthetic photon flux (100 micromoles m-2 s-1), plants grown in continuous light had higher leaf ABA levels than plants grown using an 18 or 21 h photoperiod.

  16. In Vitro Propagation, Phytochemical Analysis, and Evaluation of Free Radical Scavenging Property of Scrophularia kakudensis Franch Tissue Extracts.

    Science.gov (United States)

    Manivannan, Abinaya; Soundararajan, Prabhakaran; Park, Yoo Gyeong; Jeong, Byoung Ryong

    2015-01-01

    The current study deals with in vitro propagation, antioxidant property estimation, and assessment of acacetin content in Scrophularia kakudensis Franch. Adventitious shoot induction was achieved from the nodal explant with the highest number of adventitious shoots per explant (17.4) on Murashige and Skoog's (MS) medium fortified with 2.0 mg·L(-1) 6-benzyladenine (BA) and 0.5 mg L(-1) indole-3-acetic acid (IAA). Maximum number of roots per plant (16.5) was noted in half strength MS medium supplemented with 0.5 mg·L(-1) IAA. The regenerated plants displayed successful survival ratio (95%) in the greenhouse. The highest content of acacetin, a pharmaceutically important flavonoid, was observed in the shoot extracts (in vitro: 32.83 µg·g(-1) FW; in vivo: 30.05 µg·g(-1) FW) followed by root extracts. Total phenol and flavonoid contents along with free radical scavenging assays revealed the occurrence of larger amount of antioxidants in shoot extract in comparison with callus and root extracts of S. kakudensis. Thus, the outcome of the present study can be highly beneficial for the germplasm conservation and commercial cultivation of S. kakudensis for therapeutic purposes.

  17. Simultaneous analysis of different classes of phytohormones in coconut (Cocos nucifera L.) water using high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry after solid-phase extraction.

    Science.gov (United States)

    Ma, Zhen; Ge, Liya; Lee, Anna S Y; Yong, Jean Wan Hong; Tan, Swee Ngin; Ong, Eng Shi

    2008-03-10

    Coconut (Cocos nucifera L.) water, which contains many uncharacterized phytohormones is extensively used as a growth promoting supplement in plant tissue culture. In this paper, a high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of various classes phytohormones, including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), abscisic acid (ABA), gibberellic acid (GA), zeatin (Z), N(6)-benzyladenine (BA), alpha-naphthaleneacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) in young coconut water (CW). The analysis was carried out using a reverse-phase HPLC gradient elution, with an aqueous mobile phase (containing 0.1% formic acid, pH adjusted to 3.2 with triethylamine (TEA)) modified by methanol, and solute detection made at 265 nm wavelength. The method was validated for specificity, quantification, accuracy and precision. After preconcentration of putative endogenous phytohormones in CW using C(18) solid-phase extraction (SPE) cartridges, the HPLC method was able to screen for putative endogenous phytohormones present in CW. Finally, the identities of the putative phytohormones present in CW were further confirmed using independent liquid chromatography-tandem mass spectrometry (LC-MS/MS) equipped with an electrospray ionization (ESI) interface.

  18. The effect of sodium valproate on acetic acid-induced colitis in rats.

    Science.gov (United States)

    Najafi, Ali; Motaghi, Ehsan; Hosseini, Mohammad Javad; Ghasemi-Pirbaluti, Masoumeh

    2017-02-01

    Ulcerative colitis is a chronic recurrent disease with incomplete treatment options. The current article evaluated the effect of sodium valproate on acetic acid-induced ulcerative colitis in rats. Rats were randomly distributed into six groups including Sham group, colitis control group, sodium valproate treatment groups (50, 100 and 300 mg/kg, i.p.) and dexamethasone-treatment group. Dexamethasone was used as a reference drug. Colitis was induced by intracolonic instillation of 2 mL of 3% acetic acid solution. The efficacy of sodium valproate was evaluated by macroscopical and histopathological scoring systems, hematocrit measurement as well as biochemical analysis including myeloperoxidase (MPO) and pro-inflammatory cytokines assessment. Sodium valproate, particularly with doses of 100 and 300 mg/kg significantly improved weight loss, and macroscopic damage, reduced ulcer area, colon weight, microscopic colitis index and elevated hematocrit level. Biochemical experiments showed elevated levels of colonic MPO activity, interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in colitis control group. Treatment with sodium valproate at the doses of 100 and 300 mg/Kg) decreased the MPO activity and colonic concentrations of IL-1β, IL-6 and TNF-α. The results provide evidence that sodium valproate has a protective effect in acetic acid-induced ulcerative colitis which might be due to its anti-inflammatory activities, and it may be useful in patients with ulcerative colitis.

  19. Isolation, cytotoxic evaluation, and simultaneous quantification of eight bioactive secondary metabolites from Cicer microphyllum by high-performance thin-layer chromatography.

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    Dar, Alamgir A; Rath, Santosh K; Qaudri, Afnan; Singh, Buddh; Tasduq, Sheikh A; Kumar, Anil; Sangwan, Payare L

    2015-12-01

    Chemical investigation of Cicer microphyllum resulted in the isolation and characterization of eight natural products viz. Stigmasterol, Oleanolic acid-3-acetate, Oleanolic acid, Biochanin A, Genistein, Pratensein, Chrysoeriol, and Luteolin. Herein, we report a novel, accurate, and cost-effective high-performance thin-layer chromatography method for the simultaneous quantification of the isolated natural products on silica-gel 60F254 plates using the solvent system n-hexane/ethyl acetate/formic acid (9.0:6.5:0.8, v/v/v). Natural products were quantified after postchromatographic derivatization with ceric ammonium sulfate. The method was validated as per the International Conference on Harmonization guidelines. All calibration curves showed a good linear relationship (r > 0.9943) within the test range. Precision was assessed by intra- and interday tests with relative standard deviations <1.82%, accuracy validation recovery 98.38-99.57% with relative standard deviations <1.00%. On quantification, Pratensein was a major constituent (0.921%). The screening for cytotoxic activity using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay resulted into identification of Luteolin as potent molecule with IC50 3.5 and 25.6 μg/mL against murine melanoma and human epidermoid carcinoma cell lines, respectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Characterization of monoaminergic systems in brain regions of prematurely ageing mice.

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    De la Fuente, Monica; Hernanz, Angel; Medina, Sonia; Guayerbas, Noelia; Fernández, Beatriz; Viveros, Maria Paz

    2003-07-01

    We have previously shown that differences in life span among members of Swiss mouse populations appear to be related to their exploration of a T-maze, with a slow exploration ("slow mice") being linked to increased levels of emotionality/anxiety, an impaired immune function and a shorter life span. Thus, we proposed the slow mice as prematurely ageing mice (PAM). We have now compared the monoaminergic systems of the PAM and of the non-prematurely ageing mice (NPAM), in discrete brain regions. PAM had decreased noradrenaline (NA) levels in all the brain regions analysed, whereas the 3-methoxy-4-hydroxyphenyl glycol (MHPG)/NA ratios were not significantly modified. PAM also showed decreased serotonine (5-HT) levels in hypothalamus, striatum and midbrain, as well as increased 5-hydroxyindol-3-acetic acid (5-HIAA)/5-HT ratios in hypothalamus and hippocampus. The dopamine (DA) content was lower in PAM in most regions, whereas the 3,4-dihydroxyphenylacetic acid (DOPAC)/DA and homovanillic acid (HVA)/DA ratios were either increased or unchanged depending on the region analysed. In most cases, the differences between PAM and NPAM involved both sexes. One exception was the hypothalamus where the differences only affected the male mice. The neurochemical alterations found in PAM resemble some changes reported for aged animals and are related with their behavioural features.

  1. Endogenous hormones response to cytokinins with regard to organogenesis in explants of peach (Prunus persica L. Batsch) cultivars and rootstocks (P. persica × Prunus dulcis).

    Science.gov (United States)

    Pérez-Jiménez, Margarita; Cantero-Navarro, Elena; Pérez-Alfocea, Francisco; Cos-Terrer, José

    2014-11-01

    Organogenesis in peach (Prunus persica L. Batsch) and peach rootstocks (P. persica × Prunus dulcis) has been achieved and the action of the regeneration medium on 7 phytohormones, zeatin (Z), zeatin riboside (ZR), indole-3-acetic acid (IAA), abscisic acid (ABA), ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), salicylic acid (SA), and jasmonic acid (JA), has been studied using High performance liquid chromatography - mass spectrometry (HPLC-MS/MS). Three scion peach cultivars, 'UFO-3', 'Flariba' and 'Alice Bigi', and the peach × almond rootstocks 'Garnem' and 'GF677' were cultured in two different media, Murashige and Skoog supplemented with plant growth regulators (PGRs) (regeneration medium) and without PGRs (control medium), in order to study the effects of the media and/or genotypes in the endogenous hormones content and their role in organogenesis. The highest regeneration rate was obtained with the peach × almond rootstocks and showed a lower content of Z, IAA, ABA, ACC and JA. Only Z, ZR and IAA were affected by the action of the culture media. This study shows which hormones are external PGRs-dependent and what is the weight of the genotype and hormones in peach organogenesis that provide an avenue to manipulate in vitro organogenesis in peach.

  2. Micropropagation and assessment of genetic fidelity of Henckelia incana: an endemic and medicinal Gesneriad of South India.

    Science.gov (United States)

    Prameela, J; Ramakrishnaiah, H; Krishna, V; Deepalakshmi, A P; Naveen Kumar, N; Radhika, R N

    2015-07-01

    Henckelia incana is an endemic medicinal plant used for the treatment of fever and skin allergy. In the present study shoot regeneration was evaluated on Murashige and Skoog's (MS) medium supplemented with auxins, Indole-3-acetic acid (IAA), Indole-3- butyric acid (IBA), 1-Naphthaleneacetic acid (NAA), 2, 4-Dichlorophenoxyacetic acid (2, 4-D) and cytokinins, 6-Benzylaminopurine (BAP) and Kinetin (Kn) at concentrations of 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 mgl(-1). MS medium with IBA (18.08), NAA (17.83) and IAA (17.58) at 0.5 mgl(-1) concentrations showed efficient regeneration. Regenerated shoots were rooted on half-strength MS medium with and without 0.5 mgl(-1) IBA or NAA. The plantlets were successfully hardened in rooting trays (peat, vermiculite and sand) and transferred to field mileu. The genetic fidelity of in vitro raised plants was assessed by using three different single primer amplification reaction (SPAR) markers namely random amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR) and direct amplification of mini-satellite DNA region (DAMD). The results consistently demonstrated true-to-true type propagation. This is the first report of in vitro propagation and establishment of true-to-true type genetic fidelity in H. incana.

  3. Micropropagation of bioencapsulation and ultrastructural features of sainfoin (Onobrychis viciifolia) grown in vivo and in vitro.

    Science.gov (United States)

    Mohajer, Sadegh; Mat Taha, Rosna; Mohajer, Minoo; Khorasani Esmaeili, Arash

    2014-01-01

    To explore the potential of in vitro rapid regeneration, three varieties (Golpaygan-181, Orumieh-1763, and Gorgan-1601) of sainfoin (Onobrychis viciifolia Scop. syn. Onobrychis sativa L.) were evaluated. For the first time, an encapsulation protocol was established from somatic embryogenic callus in torpedo and cotyledonary stages to create artificial seeds. Callus derived from different concentrations of Kinetin (0-2.0 mg L(-1)) and Indole-3-acetic acid (0-2.0 mg L(-1)) was coated with sodium alginate and subsequently cultured either in Murashige and Skoog (MS) medium or in soil substrate. Adventitious shoots from synthetic beads developed into rooting in full and half strength MS medium supplemented with various concentrations of auxin and cytokinin. Prolonged water conservation of black and red soils (1:1) had the highest rate of survival plantlets in the acclimatization process. Diverse resistance techniques in Onobrychis viciifolia were evaluated when the plants were subjected to water deficiency. Higher frequency of epicuticular waxes was observed in in vivo leaves compared to in vitro leaves. Jagged trichomes nonsecreting glands covered by spines were only observed in the lower leaf side. Ultimately, stomata indices were 0.127 (abaxial), 0.188 (adaxial) in in vivo and 0.121 (abaxial), 0.201 (adaxial) in in vitro leaves.

  4. An efficient system for in vitro propagation of Bouchea fluminensis (Vell. Mold. (Verbenaceae

    Directory of Open Access Journals (Sweden)

    Cristiano Ferrara de Resende

    2014-06-01

    Full Text Available This study aimed to establish and propagate in vitro plants of Bouchea fluminensis, a medicinal species known in Brazil as gervão-falso ("false verbena", evaluating the influences of different growth regulators on in vitro multiplication and rooting stages, as well as examining ex vitro acclimatization of rooted plants. Explants were established on Murashige and Skoog medium at half strength of salts and vitamins without growth regulators. For multiplication, the explants were subjected to combinations of 6-benzyladenine (BA; 0, 2.5, 5.0 and 7.5 µM and α-naphthalene-acetic acid (NAA; 0, 0.2, 0.4 and 0.6 µM. The medium found to induce the greatest number of shoot was that containing 5 µM of BA (NAA-free. For rooting, we evaluated three auxins (NAA, indole-3-acetic acid and indole-3-butyric acid; 0.1, 0.2, 0.3 and 0.4 µM, as well as a control. No differences were observed between the control and the other treatments. The auxin-free medium was deemed the most suitable, because it ensures the lowest cost in the micropropagation procedures. We obtained 100% survival of the acclimatized seedlings, and the plants showed normal vegetative and reproductive development, suggesting that the micropropagation did not alter the biological cycle of this species. The results show the importance and potential of micropropagation for biodiversity conservation of Bouchea fluminensis.

  5. Micropropagation of Gerbera (Gerbera jamesonii Bolus).

    Science.gov (United States)

    Minerva, Ghani; Kumar, Surinder

    2013-01-01

    Gerbera (Gerbera jamesonii Bolus) is one of the most popular ornamental flowers worldwide and used both as cut flower and potted plant. Some of them show excellent agronomic characters such as color, floral diameter, stem length, and vigor, which make this plant of commercial importance. Conventionally, multiplication is done through seeds or rhizome cuttings. Rapid multiplication of elite cultivars of Gerbera, with improved agronomic traits, has been achieved by using both direct and indirect tissue culture methods. Direct shoot regeneration was accomplished from stem apices on MS medium supplemented with 1 mg/L 6-benzyladenine (BA) and 1 mg/L kinetin. Indirect shoot induction succeeded from callus differentiation has been achieved on MS medium containing 2 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L indole-3-acetic acid, and 2 mg/L BA. The in vitro shoots, 4-5 cm long, were rooted by quick dipping the shoot bases for 3-5 s in 2,000 mg/L indole-3-butyric acid solution followed by transfer to the pots containing farmyard manure, soil, and sand (1:1:1 by volume). Initially, in vitro plantlets were covered with glass jars to maintain a high relative humidity (85-90%). As soon as new shoot growth begins, relative humidity is decreased by exposing them to the open environmental conditions prior transferring to the glasshouse. Indirect shoot regeneration increased the frequency of somaclonal variations. The selected somaclones were used in developing new and novel cultivars.

  6. Micropropagation ofTigridia pavonia (L.f) DC-a potential floricultural plant from twin scale explants

    Institute of Scientific and Technical Information of China (English)

    Lekha Kumar; Sincy Joseph; Narmatha Bai

    2012-01-01

    Objective:The present study was performed to standardize an effective protocol for micropropagation ofTigridia pavonia using tissue culture.Methods: The explants were cultured on Murashige and Skoog (MS) medium supplemented with cytokinins like thidiazuron (TDZ), zeatin, kinetin and auxins such as indole-3-acetic acid (IAA), 1-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA), individually at different concentrations.Results:Multiple shoots were obtained on MS medium containing either 2.0 mg/L TDZ or 2.0 mg/L IAA or 0.5 mg/L IBA and in the same medium for a long period (120 d) produced tiny bulbs at the base of the senescent leaves. TDZ favored only multiple shoots without roots, whereas IAA or IBA individually or in combination with TDZ produced rooted shoots. Shoots developed on MS medium supplemented with TDZ were rooted on MS medium containing either IBA or NAA at 0.5 mg/L. The plantlets were acclimatized in pots containing garden soil. Regenerated plantlets developed into normal plants. The plants showed 99% survival.Conclusions:The highest number of bulblets obtained in the present study represents an effective alternative to the conventional method.

  7. Selection and Assessment of Plant Growth-Promoting Rhizobacteria for Biological Control of Multiple Plant Diseases.

    Science.gov (United States)

    Liu, Ke; Newman, Molli; McInroy, John A; Hu, Chia-Hui; Kloepper, Joseph W

    2017-08-01

    A study was designed to screen individual strains of plant growth-promoting rhizobacteria (PGPR) for broad-spectrum disease suppression in vitro and in planta. In a preliminary screen, 28 of 196 strains inhibited eight different tested pathogens in vitro. In a secondary screen, these 28 strains showed broad spectrum antagonistic activity to six different genera of pathogens, and 24 of the 28 strains produced five traits reported to be related to plant growth promotion, including nitrogen fixation, phosphate solubilization, indole-3-acetic acid production, siderophore production, and biofilm formation. In advanced screens, the 28 PGPR strains selected in vitro were tested in planta for biological control of multiple plant diseases including bacterial spot of tomato caused by Xanthomonas axonopodis pv. vesicatoria, bacterial speck of tomato caused by Pseudomonas syringae pv. tomato, damping-off of pepper caused by Rhizoctonia solani, and damping-off of cucumber caused by Pythium ultimum. In all, 5 of the 28 tested strains significantly reduced three of the four tested diseases, and another 19 strains showed biological control to two tested diseases. To understand the observed broad-spectrum biocontrol capacity, antiSMASH was used to predict secondary metabolite clusters of selected strains. Multiple gene clusters encoding for secondary metabolites, e.g., bacillibactin, bacilysin, and microcin, were detected in each strain. In conclusion, selected individual PGPR strains showed broad-spectrum biocontrol activity to multiple plant diseases.

  8. IN VITRO RHIZOGENESIS IN PAPAYA (CARICA PAPAYA L.

    Directory of Open Access Journals (Sweden)

    Jaime A. TEIXEIRA DA SILVA

    2013-12-01

    Full Text Available The seeds of two papaya (Carica papaya L. cultivars ('Rainbow' and 'Sunrise Solo' were germinated on Murashige and Skoog (MS medium with 3% sucrose, and free of plant growth regulators. Papaya contains some important secondary metabolites such as papain, and there would be interest in the in vitro mass production of papaya tissue of uniform origin. The most obvious form would be through the induction of somatic embryos, but rhizogenesis, an unexplored method, could provide as-yet unknown advantages. In this study, with the objective of artificaially inducing rhizogenesis in vitro, young leaves of both cultivars were placed on MS basal medium exposed to 5 concentrations (0, 1, 2, 4 or 8 mg/l of auxins (2,4,5-trichlorophenoxyacetic acid, 2,4,5-T; indole-3-acetic acid, IAA; indole-3-butyric acid, IBA; α-naphthaleneacetic acid, NAA; β-naphthoxyacetic acid, BNOA or phloroglucinol. All auxins could induce adventitious roots. Most roots (23/explant formed with 2 mg/l NAA. The ability to induce only roots without any other intermediary organs such as callus or shoots provides an exclusive system for possible root-specific secondary metabolite production without the need for transgenic technologies such as Agrobacterium rhizogenes, or could provide a model protocol for more in-depth developmental studies on root development in papaya, an unexplored topic for this tropical plant.

  9. Genome-wide survey of Aux/IAA gene family members in potato (Solanum tuberosum): Identification, expression analysis, and evaluation of their roles in tuber development.

    Science.gov (United States)

    Gao, Junpeng; Cao, Xiaoli; Shi, Shandang; Ma, Yuling; Wang, Kai; Liu, Shengjie; Chen, Dan; Chen, Qin; Ma, Haoli

    2016-03-04

    The Auxin/indole-3-acetic acid (Aux/IAA) genes encode short-lived nuclear proteins that are known to be involved in the primary cellular responses to auxin. To date, systematic analysis of the Aux/IAA genes in potato (Solanum tuberosum) has not been conducted. In this study, a total of 26 potato Aux/IAA genes were identified (designated from StIAA1 to StIAA26), and the distribution of four conserved domains shared by the StIAAs were analyzed based on multiple sequence alignment and a motif-based sequence analysis. A phylogenetic analysis of the Aux/IAA gene families of potato and Arabidopsis was also conducted. In order to assess the roles of StIAA genes in tuber development, the results of RNA-seq studies were reformatted to analyze the expression patterns of StIAA genes, and then verified by quantitative real-time PCR. A large number of StIAA genes (12 genes) were highly expressed in stolon organs and in during the tuber initiation and expansion developmental stages, and most of these genes were responsive to indoleacetic acid treatment. Our results suggested that StIAA genes were involved in the process of tuber development and provided insights into functional roles of potato Aux/IAA genes.

  10. Combination of the auxins NAA, IBA, and IAA with GA3 improves the commercial seed-tuber production of potato (Solanum tuberosum L.) under in vitro conditions.

    Science.gov (United States)

    Kumlay, Ahmet Metin

    2014-01-01

    The study compared the effects of 1.0 × MS medium containing various concentrations of α-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA), alone or in combination with gibberellic acid (GA3) in micropropagation of three potato (Solanum tuberosum L.) cultivars Pasinler, Granola, and Caspar using binodal stem cuttings. The results testified improved regeneration on 1.0 × MS medium containing variants of NAA, IAA, and IBA plus GA3 on all cultivars. The minimum days to shoot induction on three cultivars ranged 4.25-5 d on 1.0 × MS medium containing 0.25 mg L(-1) GA3 + 1 mg L(-1) NAA. The longest shoots (11.8 cm), maximum number of nodes (13.50), and maximum number of leaves (11.00) were recorded on cv. Caspar on 1.0 × MS medium containing 1 mg L(-1) NAA + 0.25 mg L(-1) GA3. The minimum time to root induction (12.25 d) was noted on cv. Pasinler on the same medium. All of the regenerated shoots could be easily rooted. The results showed that the combined effect of various concentrations of NAA, IAA, and IBA plus GA3 was more pronounced compared to the auxins used alone. The results of this research are of significant importance for potato breeders.

  11. Water stress, CO2 and photoperiod influence hormone levels in wheat

    Science.gov (United States)

    Nan, Rubin; Carman, John G.; Salisbury, Frank B.; Campbell, W. F. (Principal Investigator)

    2002-01-01

    'Super Dwarf' wheat (Triticum aestivum L.) plants have been grown from seed to maturity in the Mir space station where they were periodically exposed, because of microgravity and other constraints, to water deficit, waterlogging, high CO2 levels, and low light intensities. The plants produced many tillers, but none of them produced viable seed. Studies have been initiated to determine why the plants responded in these ways. In the present study, effects of the listed stresses on abscisic acid (ABA), indole-3-acetic acid (IAA) and isopentenyl adenosine ([9R]iP) levels in roots and leaves of plants grown under otherwise near optimal conditions on earth were measured. Hormones were extracted, purified by HPLC, and quantified by noncompetitive indirect ELISA. In response to water deficit, ABA levels increased in roots and leaves, IAA levels decreased in roots and leaves, and [9R]iP levels increased in leaves but decreased in roots. In response to waterlogging, ABA, IAA and [9R]iP levels briefly increased in roots and leaves and then decreased. When portions of the root system were exposed to waterlogging and/or water deficit, ABA levels in leaves increased while [9R]iP and IAA levels decreased. These responses were correlated with the percentage of the root system stressed. At a low photosynthetic photon flux (100 micromoles m-2 s-1), plants grown in continuous light had higher leaf ABA levels than plants grown using an 18 or 21 h photoperiod.

  12. Cinnamic acid increases lignin production and inhibits soybean root growth.

    Directory of Open Access Journals (Sweden)

    Victor Hugo Salvador

    Full Text Available Cinnamic acid is a known allelochemical that affects seed germination and plant root growth and therefore influences several metabolic processes. In the present work, we evaluated its effects on growth, indole-3-acetic acid (IAA oxidase and cinnamate 4-hydroxylase (C4H activities and lignin monomer composition in soybean (Glycine max roots. The results revealed that exogenously applied cinnamic acid inhibited root growth and increased IAA oxidase and C4H activities. The allelochemical increased the total lignin content, thus altering the sum and ratios of the p-hydroxyphenyl (H, guaiacyl (G, and syringyl (S lignin monomers. When applied alone or with cinnamic acid, piperonylic acid (PIP, a quasi-irreversible inhibitor of C4H reduced C4H activity, lignin and the H, G, S monomer content compared to the cinnamic acid treatment. Taken together, these results indicate that exogenously applied cinnamic acid can be channeled into the phenylpropanoid pathway via the C4H reaction, resulting in an increase in H lignin. In conjunction with enhanced IAA oxidase activity, these metabolic responses lead to the stiffening of the cell wall and are followed by a reduction in soybean root growth.

  13. Bioprospecting of plant growth promoting psychrotrophic Bacilli from the cold desert of north western Indian Himalayas.

    Science.gov (United States)

    Yadav, Ajar Nath; Sachan, Shashwati Ghosh; Verma, Priyanka; Saxena, Anil Kumar

    2016-02-01

    The plant growth promoting psychrotrophic Bacilli were investigated from different sites in north western Indian Himalayas. A total of 247 morphotypes were obtained from different soil and water samples and were grouped into 43 clusters based on 16S rDNA-RFLP analysis with three restriction endonucleases. Sequencing of representative isolates has revealed that these 43 Bacilli belonged to different species of 11 genera viz., Desemzia, Exiguobacterium, Jeotgalicoccus, Lysinibacillus, Paenibacillus, Planococcus, Pontibacillus, Sinobaca, Sporosarcina, Staphylococcus and Virgibacillus. With an aim to develop microbial inoculants that can perform efficiently at low temperatures, all representative isolates were screened for different plant growth promoting traits at low temperatures (5-15 degrees C). Among the strains, variations were observed for production (%) of indole-3-acetic acid (20), ammonia (19), siderophores (11), gibberellic acid (4) and hydrogen cyanide (2); solubilisation (%) of zinc (14), phosphate (13) and potassium (7); 1-aminocyclopropane-1-carboxylate deaminase activity (6%) and biocontrol activity (4%) against Rhizoctonia solani and Macrophomina phaseolina. Among all the strains, Bacillus licheniformis, Bacillus muralis, Desemzia incerta, Paenibacillus tylopili and Sporosarcina globispora were found to be potent candidates to be developed as inoculants as they exhibited multiple PGP traits at low temperature.

  14. Micropropagation of Bioencapsulation and Ultrastructural Features of Sainfoin (Onobrychis viciifolia Grown In Vivo and In Vitro

    Directory of Open Access Journals (Sweden)

    Sadegh Mohajer

    2014-01-01

    Full Text Available To explore the potential of in vitro rapid regeneration, three varieties (Golpaygan-181, Orumieh-1763, and Gorgan-1601 of sainfoin (Onobrychis viciifolia Scop. syn. Onobrychis sativa L. were evaluated. For the first time, an encapsulation protocol was established from somatic embryogenic callus in torpedo and cotyledonary stages to create artificial seeds. Callus derived from different concentrations of Kinetin (0–2.0 mg L−1 and Indole-3-acetic acid (0–2.0 mg L−1 was coated with sodium alginate and subsequently cultured either in Murashige and Skoog (MS medium or in soil substrate. Adventitious shoots from synthetic beads developed into rooting in full and half strength MS medium supplemented with various concentrations of auxin and cytokinin. Prolonged water conservation of black and red soils (1 : 1 had the highest rate of survival plantlets in the acclimatization process. Diverse resistance techniques in Onobrychis viciifolia were evaluated when the plants were subjected to water deficiency. Higher frequency of epicuticular waxes was observed in in vivo leaves compared to in vitro leaves. Jagged trichomes nonsecreting glands covered by spines were only observed in the lower leaf side. Ultimately, stomata indices were 0.127 (abaxial, 0.188 (adaxial in in vivo and 0.121 (abaxial, 0.201 (adaxial in in vitro leaves.

  15. Biotransformation of antibiotics. I. Acylation of chloramphenicol by spores of Streptomyces griseus isolated from the Egyptian soil .

    Science.gov (United States)

    El-Kersh, T A; Plourde, J R

    1976-03-01

    Incubation of spores, washed mycelium or whole cultures of a Streptomyces sp. with chloramphenicol (I) resulted in the loss of in vitro bioactivity of the antibiotic. Gas chromatographic estimation of an appropriate extract revealed that more than 95% of the antibiotic was inactivated under the specified conditions. The spores inactivated chloramphenicol in an inorganic buffer solution, or in distilled water, without the addition of carbohydrate or external co-factor. However, addition of certain carbon sources to the spores showed a pronounced effect on the chloramphenicol transformation process and on the relative concentration of the inactivated products. Time-course studies on the spore-catalyzed chloramphenicol transformation activity showed a maximum activity at 12-hour incubation. Addition of glucose or acetate at this point maintained maximum activity. The transformation products were identified as: chloramphenicol-1-acetate (IIa); chloramphenicol-3-acetate (IIb); chloramphenicol-3-propionate (III); CHLORAMPHENICOL-O-ISOBUTYRATE (IV); chloramphenicol-3-butyrate (V); and chloramphenicol-3-isovalerate (VI), by techniques of TLC, CPC, GC, UV, IR, MS and NMR. The microbial characteristics of the isolated strain include the formation of flexuous gray aerial mycelium with smooth to rough spores, irregular in size. It is an H2S and melanin former, non-chromogenic, and was inhibited by a streptomycin-producing strain of Streptomyces griseus (Krainsky 1914) Waksman and Henrici(1948).

  16. Genome-wide identification, isolation and expression analysis of auxin response factor (ARF) gene family in sweet orange (Citrus sinensis).

    Science.gov (United States)

    Li, Si-Bei; OuYang, Wei-Zhi; Hou, Xiao-Jin; Xie, Liang-Liang; Hu, Chun-Gen; Zhang, Jin-Zhi

    2015-01-01

    Auxin response factors (ARFs) are an important family of proteins in auxin-mediated response, with key roles in various physiological and biochemical processes. To date, a genome-wide overview of the ARF gene family in citrus was not available. A systematic analysis of this gene family in citrus was begun by carrying out a genome-wide search for the homologs of ARFs. A total of 19 nonredundant ARF genes (CiARF) were found and validated from the sweet orange. A comprehensive overview of the CiARFs was undertaken, including the gene structures, phylogenetic analysis, chromosome locations, conserved motifs of proteins, and cis-elements in promoters of CiARF. Furthermore, expression profiling using real-time PCR revealed many CiARF genes, albeit with different patterns depending on types of tissues and/or developmental stages. Comprehensive expression analysis of these genes was also performed under two hormone treatments using real-time PCR. Indole-3-acetic acid (IAA) and N-1-napthylphthalamic acid (NPA) treatment experiments revealed differential up-regulation and down-regulation, respectively, of the 19 citrus ARF genes in the callus of sweet orange. Our comprehensive analysis of ARF genes further elucidates the roles of CiARF family members during citrus growth and development process.

  17. Simultaneous quantification of phytohormones in fermentation extracts of Botryodiplodia theobromae by liquid chromatography-electrospray tandem mass spectrometry.

    Science.gov (United States)

    Castillo, Grolamys; Torrecillas, Alejandro; Nogueiras, Clara; Michelena, Georgina; Sánchez-Bravo, José; Acosta, Manuel

    2014-07-01

    Fermentation broth and biomass from three strains of Botryodiplodia theobromae were characterized by high performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-ESI-MS/MS) method, in order to quantify different phytohormones and to identify amino acid conjugates of jasmonic acid (JA) present in fermentation broths. A liquid-liquid extraction with ethyl acetate was used as sample preparation. The separation was carried out on a C18 reversed-phase HPLC column followed by analysis via ESI-MS/MS. The multiple reaction monitoring mode was used for quantitative measurement. For the first time, indole-3-acetic acid, indole-3-propionic acid, indole-3-butyric acid and JA were identified and quantified in the ethyl acetate extracts from the biomass, after the separation of mycelium from supernatant. The fermentation broths showed significantly higher levels of JA in relation to the other phytohormones. This is the first report of the presence of gibberellic acid, abscisic acid, salicylic acid and the cytokinins zeatin, and zeatin riboside in fermentation broths of Botryodiplodia sp. The presence of JA-serine and JA-threonine conjugates in fermentation broth was confirmed using HPLC-ESI tandem mass spectrometry in negative ionization mode, while the occurrence of JA-glycine and JA-isoleucine conjugates was evidenced with the same technique but with positive ionization. The results demonstrated that the used HPLC-ESI-MS/MS method was effective for analysing phytohormones in fermentation samples.

  18. Thermodynamics of the hydrolysis reactions of nitriles

    Energy Technology Data Exchange (ETDEWEB)

    Tewari, Yadu B. [Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States)]. E-mail: yadu.tewari@nist.gov; Goldberg, Robert N. [Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States)]. E-mail: robert.goldberg@nist.gov

    2005-07-15

    Microcalorimetry and high-performance liquid chromatography (h.p.l.c) have been used to conduct a thermodynamic investigation of the following nitrilase catalyzed reactions: (1) benzonitrile(aq) + 2H{sub 2}O(l) = benzoic acid(aq) + ammonia(aq), (2) benzylcyanide(aq) + 2H{sub 2}O(l) = benzeneacetic acid(aq) + ammonia(aq) (3) 3-phenylpropionitrile(aq) + 2H{sub 2}O(l) 3-phenylpropanoic acid(aq) + ammonia(aq), (4) 4-phenylbutyonitrile(aq) + 2H{sub 2}O(l) = 4-phenylbutyric acid(aq) + ammonia(aq), (5) {alpha}-methylbenzyl cyanide(aq) + 2H{sub 2}O(l) = {alpha}-methylbenzene acetic acid(aq) + ammonia(aq), and (6) 3-indoleacetonitrile(aq) + 2H{sub 2}O(l) = indole-3-acetic acid(aq) + ammonia(aq). The equilibrium measurements showed that these reactions proceeded to completion. Thus, it was possible to set only lower limits for the values of the apparent equilibrium constants K'. However, it was possible to obtain precise values of the calorimetrically determined molar enthalpies of reaction {delta}{sub r} H {sub m}(cal). These values were then used in conjunction with an equilibrium model to calculate values of the standard molar enthalpies for chemical reference reactions that correspond to the above overall biochemical reactions.

  19. Alleviation of salt stress by halotolerant and halophilic plant growth-promoting bacteria in wheat (Triticum aestivum

    Directory of Open Access Journals (Sweden)

    Furkan Orhan

    Full Text Available ABSTRACT In the current study, 18 halotolerant and halophilic bacteria have been investigated for their plant growth promoting abilities in vitro and in a hydroponic culture. The bacterial strains have been investigated for ammonia, indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate-deaminase production, phosphate solubilisation and nitrogen fixation activities. Of the tested bacteria, eight were inoculated with Triticum aestivum in a hydroponic culture. The investigated bacterial strains were found to have different plant-growth promoting activities in vitro. Under salt stress (200 mM NaCl, the investigated bacterial strains significantly increased the root and shoot length and total fresh weight of the plants. The growth rates of the plants inoculated with bacterial strains ranged from 62.2% to 78.1%.Identifying of novel halophilic and halotolerant bacteria that promote plant growth can be used as alternatives for salt sensitive plants. Extensive research has been conducted on several halophilic and halotolerant bacterial strains to investigate their plant growth promoting activities. However, to the best of my knowledge, this is the first study to inoculate these bacterial strains with wheat.

  20. Extracts and constituents of Rubus chingii with 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity.

    Science.gov (United States)

    Ding, Hsiou-Yu

    2011-01-01

    The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the fruits of Rubus chingii was studied in vitro. Ethanolic extract, ethyl acetate and n-butanol fractions from dried R. chingii fruits revealed strong DPPH free radical scavenging activity with IC(50) values of 17.9, 3.4 and 4.0 μg/mL, respectively. The ethyl acetate and n-butanol fractions were further purified by a combination of silica gel chromatography, Lobar RP-8 chromatography, and high-pressure liquid chromatography (HPLC). Nine compounds were isolated, where methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), vanillic acid (5), kaempferol (7), and tiliroside (9) showed stronger DPPH free radical scavenging activity than that of ascorbic acid (131.8 μM) with IC(50) values of 45.2, 34.9, 78.5, and 13.7 μM, respectively. In addition, rubusine (1) is a new compound discovered in the present study and methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), methyl dioxindole-3-acetate (3), and 2-oxo-1,2-dihydroquinoline-4-carboxylic acid (4) were isolated from the fruits for the first time.

  1. The influence of light spectra, UV-A, and growth regulators on the in vitro seed germination of Senecio cineraria DC.

    Directory of Open Access Journals (Sweden)

    Cristiane Pimentel Victório

    2010-10-01

    Full Text Available This study was carried out to investigate the effects of light spectra, additional UV-A, and different growth regulators on the in vitro germination of Senecio cineraria DC. Seeds were surface-sterilized and inoculated in MS medium to evaluate the following light spectra: white, white plus UV-A, blue, green, red or darkness. The maximum germinability was obtained using MS0 medium under white light (30% and MS + 0.3 mg L-1 GA3 in the absence of light (30.5%. S. cineraria seeds were indifferent to light. Blue and green lights inhibited germination. Different concentrations of gibberellic acid (GA3 (0.1; 0.4; 0.6; 0.8; 1.0 and 2.0 mg L-1 and indole-3-acetic acid IAA (0.1; 0.3 and 1.0 mg L-1 were evaluated under white light and darkness. No concentration of GA3 enhanced seed germination percentage under white light. However, when the seeds were maintained in darkness, GA3 improved germination responses in all tested concentrations, except at 1.0 mg L-1. Under white light, these concentrations also increased the germination time and reduced germination rate. Germination rate, under light or darkness, was lower using IAA compared with GA3.

  2. Effect of an IAA overproducer mutant of the fungus hebeloma Cylindrosporum romagnesi on the early stages of ectomycorrhizal infection and carbohydrate content in seedlings of Pinus pinaster (ait. SOL.

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    Maria Rudawska

    2014-01-01

    Full Text Available Ectomycorrhizal and control seedlings of Pinus pinaster were cultured on a synthetic Melin-Norkrans medium in Petri dishes. Seedlings were inoculated with a mycelial slurry of an indole-3-acetic acid (IAA overproducer Hebeloma cylindrosporum mutant 331. The wild strain H. cylindrosporum hl was used as a reference. Medium was supplemented or not with glucose. The mycelial slurry appeared to be very effective for mycorrhizal inoculation even on the medium without glucose. In such culture conditions ectomycorrhizal ability of the IAA overproducer mutant 331 was significantly higher than of the comparable wild type. The highest content of soluble sugars was found in stems and roots of plants mycorrhizal with the mutant followed by mycorrhizal plants with the wild type and then by the uninoculated control. Sucrose practically disappeared from roots of mycorrhizal plants. Starch content in roots of mycorrhizal plants with the IAA overproducer mutant was lower as compared with other treatments. Fungal auxin in mycorrhizal symbiosis seems to be responsible for maintaining the source-sink relationship. This is revealed by higher sugar level in the host's photosynthetic tissue (source and the rise of soluble sugar content in roots (sink due to enhanced translocation of sugars to the roots and auxin stimulated conversion of carbohydrates (sucrose, starch of the host.

  3. Active food packaging based on molecularly imprinted polymers: study of the release kinetics of ferulic acid.

    Science.gov (United States)

    Otero-Pazos, Pablo; Rodríguez-Bernaldo de Quirós, Ana; Sendón, Raquel; Benito-Peña, Elena; González-Vallejo, Victoria; Moreno-Bondi, M Cruz; Angulo, Immaculada; Paseiro-Losada, Perfecto

    2014-11-19

    A novel active packaging based on molecularly imprinted polymer (MIP) was developed for the controlled release of ferulic acid. The release kinetics of ferulic acid from the active system to food simulants (10, 20, and 50% ethanol (v/v), 3% acetic acid (w/v), and vegetable oil), substitutes (95% ethanol (v/v) and isooctane), and real food samples at different temperatures were studied. The key parameters of the diffusion process were calculated by using a mathematical modeling based on Fick's second law. The ferulic acid release was affected by the temperature as well as the percentage of ethanol of the simulant. The fastest release occurred in 95% ethanol (v/v) at 20 °C. The diffusion coefficients (D) obtained ranged between 1.8 × 10(-11) and 4.2 × 10(-9) cm(2)/s. A very good correlation between experimental and estimated data was obtained, and consequently the model could be used to predict the release of ferulic acid into food simulants and real food samples.

  4. Extracts and Constituents of Rubus chingii with 1,1-Diphenyl-2-picrylhydrazyl (DPPH Free Radical Scavenging Activity

    Directory of Open Access Journals (Sweden)

    Hsiou-Yu Ding

    2011-06-01

    Full Text Available The 1,1-diphenyl-2-picrylhydrazyl (DPPH free radical scavenging activity of the fruits of Rubus chingii was studied in vitro. Ethanolic extract, ethyl acetate and n-butanol fractions from dried R. chingii fruits revealed strong DPPH free radical scavenging activity with IC50 values of 17.9, 3.4 and 4.0 µg/mL, respectively. The ethyl acetate and n-butanol fractions were further purified by a combination of silica gel chromatography, Lobar RP-8 chromatography, and high-pressure liquid chromatography (HPLC. Nine compounds were isolated, where methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl-acetate (2, vanillic acid (5, kaempferol (7, and tiliroside (9 showed stronger DPPH free radical scavenging activity than that of ascorbic acid (131.8 µM with IC50 values of 45.2, 34.9, 78.5, and 13.7 µM, respectively. In addition, rubusine (1 is a new compound discovered in the present study and methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl-acetate (2, methyl dioxindole-3-acetate (3, and 2-oxo-1,2-dihydroquinoline-4-carboxylic acid (4 were isolated from the fruits for the first time.

  5. A rapid and sensitive method for the analysis of brain monoamine neurotransmitters using ultra-fast liquid chromatography coupled to electrochemical detection.

    Science.gov (United States)

    Parrot, Sandrine; Neuzeret, Pierre-Charles; Denoroy, Luc

    2011-12-15

    Electrochemical detection is often used to detect catecholamines and indolamines in brain samples that have been separated by conventional reverse-phase high performance liquid chromatography (HPLC). This paper presents the transfer of an existing chromatographic method for the determination of monoamines in brain tissues using 5 μm granulometry HPLC columns to columns with a particle diameter less than 3 μm. Several parameters (repeatability, linearity, accuracy, limit of detection, and stability of samples) for this new ultrafast high performance liquid chromatography (UHPLC) method were examined after optimization of the analytical conditions. The separation of seven compounds, noradrenaline, dopamine and three of its metabolites, dihydroxyphenylacetic acid, homovanillic acid, and 3-methoxytyramine, and serotonin and its metabolite, 5-hydroxyindole-3-acetic acid was analyzed using this UHPLC-electrochemical detection method. The final method, which was applied to brain tissue extracts from mice, rats, and cats, decreased analysis time by a factor of 4 compared to HPLC, while guaranteeing good analytical performance.

  6. Efficient antibody production in the methylotrophic yeast Ogataea minuta by overexpression of chaperones.

    Science.gov (United States)

    Suzuki, Takeshi; Baba, Satoshi; Ono, Minako; Nonaka, Koichi; Ichikawa, Kimihisa; Yabuta, Masayuki; Ito, Rie; Chiba, Yasunori

    2017-08-01

    A production system for a therapeutic monoclonal antibody was developed using the methylotrophic yeast Ogataea minuta IFO10746. The genetically engineered O. minuta secreted a detectable amount of anti-TRAIL receptor antibody into the culture supernatant, and the secreted antibody was purified by multiple column chromatography steps. In the purification process, both fully and partially assembled antibodies were detected and isolated. The fully assembled antibody from O. minuta showed almost the same biological activity as that derived from mammalian cells despite the distinct glycosylation profile, whereas the partially assembled antibody showed no cytotoxic activity. To increase the production of active antibody in O. minuta, we overexpressed selected chaperone proteins (included protein disulfide isomerase (OmPDI1), thiol oxidase (OmERO1), and immunoglobulin heavy chain binding protein (OmKAR2)) known to assist in the proper folding (in the endoplasmic reticulum) of proteins destined for secretion. Each of these chaperones enhanced antibody secretion, and together these three factors yielded 16-fold higher antibody accumulation while increasing the ratio of the fully assembled antibody compared to that from the parental strain. Supplementation of a rhodanine-3-acetic acid derivative (R3AD_1c), an inhibitor of O-mannosylation, further increased the secretion of the correctly assembled antibody. These results indicated that the co-overexpression of chaperones is an effective way to produce the correctly assembled antibody in O. minuta. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. Scientific Opinion on the safety evaluation of the substance, 1,3,5-tris(2,2-dimethylpropanamidobenzene, CAS No. 745070-61-5, for use in food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-07-01

    Full Text Available This scientific opinion of EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the additive 1,3,5-tris(2,2-dimethylpropanamidobenzene with the CAS No. 745070-61-5, the Ref. No 95420, the FCM Substance No 784, for use as a nucleating agent/clarifier at a maximum use level of 250 mg/kg in polyprolylene (PP. Final articles are intended to be used in contact with all type of foods for short term contact (1 hour at temperatures up to 100 ºC and/or for long term storage at ambient temperature or below. Specific migration of the substance into 3 % acetic acid, 10 % ethanol and olive oil, was measured to be up to 48 µg/kg, 79 µg/kg and 94 µg/kg, respectively. In vitro and in vivo genotoxicity tests showed no evidence for a genotoxic potential of the substance. A 90-day dietary toxicity study in Wistar rats showed no effects at any dose and the NOAEL was considered to be 961 mg/kg bw/day in males and 1104 mg/kg bw/day in females or higher. Therefore, the CEF Panel concluded that the substance 1,3,5-tris(2,2-dimethylpropanamidobenzene does not raise a safety concern for the consumer if it is used in polyolefins and the migration does not exceed 5 mg/kg food.

  8. Identification and quantification of phytochemical composition and anti-inflammatory and radical scavenging properties of methanolic extracts of Chinese propolis.

    Science.gov (United States)

    Shi, Haiming; Yang, Haisha; Zhang, Xiaowei; Yu, Liangli Lucy

    2012-12-19

    Fifteen propolis samples collected from different regions of China were investigated and compared for their phytochemical composition and anti-inflammatory and radical scavenging properties. Eleven compounds including caffeic, p-coumaric, ferulic, isoferulic, and 3,4-dimethylcaffeic acids, pinobanksin, chrysin, pinocembrin, galangin, pinobanksin 3-acetate, and caffeic acid phenylethyl ester were quantified for the 15 propolis samples using a UHPLC method, whereas 38 compounds were identified by UPLC/Q-TOF-MS. The 15 propolis samples significantly differed in their total phenolic and total flavonoid contents, as well as their phytochemical profiles. The methanol extracts of propolis also showed significant anti-inflammatory effects in LPS-stimulated RAW 264.7 mouse macrophage cells at 10 μg propolis extract/mL concentration. Additionally, the propolis samples differed in their DPPH, ABTS cation, hydroxyl, and peroxide radical scavenging capacities and ferric reducing abilities. The results from this study may be used to improve the commercial production and consumption of Chinese propolis products.

  9. Phytotoxic Mechanism of Nanoparticles: Destruction of Chloroplasts and Vascular Bundles and Alteration of Nutrient Absorption

    Science.gov (United States)

    Nhan, Le Van; Ma, Chuanxin; Rui, Yukui; Liu, Shutong; Li, Xuguang; Xing, Baoshan; Liu, Liming

    2015-06-01

    This study focused on determining the phytotoxic mechanism of CeO2 nanoparticles (NPs): destroying chloroplasts and vascular bundles and altering absorption of nutrients on conventional and Bt-transgenic cottons. Experiments were designed with three concentrations of CeO2 NPs including: 0, 100 and 500 mg·L-1, and each treatment was three replications. Results indicate that absorbed CeO2 nanoparticles significantly reduced the Zn, Mg, Fe, and P levels in xylem sap compared with the control group and decreased indole-3-acetic acid (IAA) and abscisic acid (ABA) concentrations in the roots of conventional cotton. Transmission electron microscopy (TEM) images revealed that CeO2 NPs were absorbed into the roots and subsequently transported to the stems and leaves of both conventional and Bt-transgenic cotton plants via xylem sap. In addition, the majority of aggregated CeO2 NPs were attached to the external surface of chloroplasts, which were swollen and ruptured, especially in Bt-transgenic cotton. The vascular bundles were destroyed by CeO2 nanoparticles, and more damage was observed in transgenic cotton than conventional cotton.

  10. Phytobeneficial Properties of Bacteria Isolated from the Rhizosphere of Maize in Southwestern Nigerian Soils.

    Science.gov (United States)

    Abiala, M A; Odebode, A C; Hsu, S F; Blackwood, C B

    2015-07-01

    Biocontrol agents isolated outside Africa have performed inconsistently under field conditions in Africa. The development of indigenous phytobeneficial microbial strains that suit local environments may help enhance competitiveness with in situ microorganisms and effectiveness at suppressing local pathogen strains. We isolated bacteria from the rhizosphere of maize growing in southwestern Nigeria and assessed them for growth-promoting characteristics. The best isolates were characterized using 16S rRNA genes and were further evaluated in the greenhouse on maize seedlings. Four isolates (EBS8, IGBR11, EPR2, and ADS14) were outstanding in in vitro assays of antagonistic activity against a local strain of Fusarium verticillioides, phosphate solubilization efficiency, chitinase enzyme activity, and indole-3-acetic acid production. Inoculation of maize seeds with these isolates resulted in ≥95% maize seed germination and significantly enhanced radicle and plumule length. In the greenhouse, maize seedling height, stem girth, number of leaves, leaf area, shoot mass (dry matter), and nutrient contents were significantly enhanced. The bioprotectant and phytobeneficial effects were strongest and most consistent for isolate EBS8, which was identified as a Bacillus strain by 16S rRNA gene analysis. As a bacterial strain that exhibits multiple growth-promoting characteristics and is adapted to local conditions, EBS8 should be considered for the development of indigenous biological fertilizer treatments. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. Change of Endogenous Hormones, Amino-acid and Nutrition in Flowering Stage of Phyllostachys praecox f. prevernalis%雷竹开花期内源激素、氨基酸和营养成分含量变化

    Institute of Scientific and Technical Information of China (English)

    何奇江; 汪奎宏; 华锡奇; 童晓青

    2005-01-01

    The test site was located in Jincheng Town, Lin'an City, Zhejiang Province. The leaves, culms and rhizomes of two-year-old and three-year-old flowering individuals or non-flowering individuals were taken from the same bamboo (Phyllostachys praecox f. prevernalis ) forest. The culms and rhizomes of one-year-old flowering or non-flowering were also taken from the same bamboo forest. Based on analysis of the content of endogenous hormones, amino-acid and nutrition in flowering stage of bamboo, the results showed that abscisic acid(ABA) had main effect on accelerating its flowering and the increase of cytokinin(CTK) was also one reason for bringing flower, but indole-3-acetic acid(IAA) antagonized on its flowering. Total aminoacid in the non-flowering bamboo was 23.01 % higher than that in flowering bamboo. Aspartic acid (ASP) could delay flowering. Protein, especially protein in leaves had main effect on senescence procedure. Increase of phosphorus content in flowering bamboo could accelerate metabolizing, and therefore promote senescence of bamboo.

  12. Structure–anticancer activity relationships among 4-azolidinone-3-carboxylic acids derivatives

    Directory of Open Access Journals (Sweden)

    Lesyk R. B.

    2010-04-01

    Full Text Available The aim of present research was investigation of anticancer activity of 4-azolidinone-3-carboxylic acids derivatives, and studies of structure–activity relationships (SAR aspects. Methods. Organic synthesis; spectral methods; anticancer screening was performed according to the US NCI protocol (Developmental Therapeutic Program. Results. The data of new 4-thiazolidinone-3-alkanecarboxylic acids derivatives in vitro anticancer activity were described. The most active compounds which belong to 5-arylidene-2,4- thia(imidazolidinone-3-alkanecarboxylic acids; 5-aryl(heterylidenerhodanine-3-succinic acids derivatives were selected. Determination of some SAR aspects which allowed to determine directions in lead- compounds structure optimization, as well as desirable molecular fragments for design of potential anticancer agents based on 4-azolidinone scaffold were performed. 5-Arylidenehydantoin-3-acetic acids amides were identified as a new class of significant selective antileukemic agents. Possible pharmacophore scaffold of 5-ylidenerhodanine-3-succinic acids derivatives was suggested. Conclusions. The series of active compounds with high anticancer activity and/or selectivity levels were selected. Some SAR aspects were determined and structure design directions were proposed.

  13. OsAUX1 controls lateral root initiation in rice (Oryza sativa L.).

    Science.gov (United States)

    Zhao, Heming; Ma, Tengfei; Wang, Xin; Deng, Yingtian; Ma, Haoli; Zhang, Rongsheng; Zhao, Jie

    2015-11-01

    Polar auxin transport, mediated by influx and efflux transporters, controls many aspects of plant growth and development. The auxin influx carriers in Arabidopsis have been shown to control lateral root development and gravitropism, but little is known about these proteins in rice. This paper reports on the functional characterization of OsAUX1. Three OsAUX1 T-DNA insertion mutants and RNAi knockdown transgenic plants reduced lateral root initiation compared with wild-type (WT) plants. OsAUX1 overexpression plants exhibited increased lateral root initiation and OsAUX1 was highly expressed in lateral roots and lateral root primordia. Similarly, the auxin reporter, DR5-GUS, was expressed at lower levels in osaux1 than in the WT plants, which indicated that the auxin levels in the mutant roots had decreased. Exogenous 1-naphthylacetic acid (NAA) treatment rescued the defective phenotype in osaux1-1 plants, whereas indole-3-acetic acid (IAA) and 2,4-D could not, which suggested that OsAUX1 was a putative auxin influx carrier. The transcript levels of several auxin signalling genes and cell cycle genes significantly declined in osaux1, hinting that the regulatory role of OsAUX1 may be mediated by auxin signalling and cell cycle genes. Overall, our results indicated that OsAUX1 was involved in polar auxin transport and functioned to control auxin-mediated lateral root initiation in rice.

  14. Response difference of transgenic and conventional rice (Oryza sativa) to nanoparticles (γFe₂O₃).

    Science.gov (United States)

    Gui, Xin; Deng, Yingqing; Rui, Yukui; Gao, Binbin; Luo, Wenhe; Chen, Shili; Nhan, Le Van; Li, Xuguang; Liu, Shutong; Han, Yaning; Liu, Liming; Xing, Baoshan

    2015-11-01

    Nanoparticles (NPs) are an increasingly common contaminant in agro-environments, and their potential effect on genetically modified (GM) crops has been largely unexplored. GM crop exposure to NPs is likely to increase as both technologies develop. To better understand the implications of nanoparticles on GM plants in agriculture, we performed a glasshouse study to quantify the uptake of Fe2O3 NPs on transgenic and non-transgenic rice plants. We measured nutrient concentrations, biomass, enzyme activity, and the concentration of two phytohormones, abscisic acid (ABA) and indole-3-acetic acid (IAA), and malondialdehyde (MDA). Root phytohormone inhibition was positively correlated with Fe2O3 NP concentrations, indicating that Fe2O3 had a significant influence on the production of these hormones. The activities of antioxidant enzymes were significantly higher as a factor of low Fe2O3 NP treatment concentration and significantly lower at high NP concentrations, but only among transgenic plants. There was also a positive correlation between the treatment concentration of Fe2O3 and iron accumulation, and the magnitude of this effect was greatest among non-transgenic plants. The differences in root phytohormone production and antioxidant enzyme activity between transgenic and non-transgenic rice plants in vivo suggests that GM crops may react to NP exposure differently than conventional crops. It is the first study of NPs that may have an impact on GM crops, and a realistic significance for food security and food safety.

  15. Heat-induced phytohormone changes are associated with disrupted early reproductive development and reduced yield in rice

    Science.gov (United States)

    Wu, Chao; Cui, Kehui; Wang, Wencheng; Li, Qian; Fahad, Shah; Hu, Qiuqian; Huang, Jianliang; Nie, Lixiao; Peng, Shaobing

    2016-01-01

    Heat stress causes morphological and physiological changes and reduces crop yield in rice (Oryza sativa). To investigate changes in phytohormones and their relationships with yield and other attributes under heat stress, four rice varieties (Nagina22, Huanghuazhan, Liangyoupeijiu, and Shanyou 63) were grown in pots and subjected to three high temperature treatments plus control in temperature-controlled greenhouses for 15 d during the early reproductive phase. Yield reductions in Nagina22, Huanghuazhan, and Liangyoupeijiu were attributed to reductions in spikelet fertility, spikelets per panicle, and grain weight. The adverse effects of high temperature were alleviated by application of exogenous 6-benzylaminopurine (6-BA) in the heat-susceptible Liangyoupeijiu. High temperature stress reduced active cytokinins, gibberellin A1 (GA1), and indole-3-acetic acid (IAA), but increased abscisic acid (ABA) and bound cytokinins in young panicles. Correlation analyses and application of exogenous 6-BA revealed that high temperature-induced cytokinin changes may regulate yield components by modulating the differentiation and degradation of branches and spikelets, panicle exsertion, pollen vigor, anther dehiscence, and grain size. Heat-tolerant Shanyou 63 displayed minor changes in phytohormones, panicle formation, and grain yield under high temperature compared with those of the other three varieties. These results suggest that phytohormone changes are closely associated with yield formation, and a small reduction or stability in phytohormone content is required to avoid large yield losses under heat stress. PMID:27713528

  16. Development of Electrically Conductive Double-Network Hydrogels via One-Step Facile Strategy for Cardiac Tissue Engineering.

    Science.gov (United States)

    Yang, Boguang; Yao, Fanglian; Hao, Tong; Fang, Wancai; Ye, Lei; Zhang, Yabin; Wang, Yan; Li, Junjie; Wang, Changyong

    2016-02-18

    Cardiac tissue engineering is an effective method to treat the myocardial infarction. However, the lack of electrical conductivity of biomaterials limits their applications. In this work, a homogeneous electronically conductive double network (HEDN) hydrogel via one-step facile strategy is developed, consisting of a rigid/hydrophobic/conductive network of chemical crosslinked poly(thiophene-3-acetic acid) (PTAA) and a flexible/hydrophilic/biocompatible network of photo-crosslinking methacrylated aminated gelatin (MAAG). Results suggest that the swelling, mechanical, and conductive properties of HEDN hydrogel can be modulated via adjusting the ratio of PTAA network to MAAG network. HEDN hydrogel has Young's moduli ranging from 22.7 to 493.1 kPa, and its conductivity (≈10(-4) S cm(-1)) falls in the range of reported conductivities for native myocardium tissue. To assess their biological activity, the brown adipose-derived stem cells (BADSCs) are seeded on the surface of HEDN hydrogel with or without electrical stimulation. Our data show that the HEDN hydrogel can support the survival and proliferation of BADSCs, and that it can improve the cardiac differentiation efficiency of BADSCs and upregulate the expression of connexin 43. Moreover, electrical stimulation can further improve this effect. Overall, it is concluded that the HEDN hydrogel may represent an ideal scaffold for cardiac tissue engineering.

  17. Wastewater treatment, energy recovery and desalination using a forward osmosis membrane in an air-cathode microbial osmotic fuel cell

    KAUST Repository

    Werner, Craig M.

    2013-02-01

    A microbial osmotic fuel cell (MOFC) has a forward osmosis (FO) membrane situated between the electrodes that enable desalinated water recovery along with power generation. Previous designs have required aerating the cathode chamber water, offsetting the benefits of power generation by power consumption for aeration. An air-cathode MOFC design was developed here to improve energy recovery, and the performance of this new design was compared to conventional microbial fuel cells containing a cation (CEM) or anion exchange membrane (AEM). Internal resistance of the MOFC was reduced with the FO membrane compared to the ion exchange membranes, resulting in a higher maximum power production (43W/m3) than that obtained with an AEM (40W/m3) or CEM (23W/m3). Acetate (carbon source) removal reached 90% in the MOFC; however, a small amount of acetate crossed the membrane to the catholyte. The initial water flux declined by 28% from cycle 1 to cycle 3 of operation but stabilized at 4.1L/m2/h over the final three batch cycles. This decline in water flux was due to membrane fouling. Overall desalination of the draw (synthetic seawater) solution was 35%. These results substantially improve the prospects for simultaneous wastewater treatment and seawater desalination in the same reactor. © 2012 Elsevier B.V.

  18. Effects of indole amides on lettuce and onion germination and growth.

    Science.gov (United States)

    Borgati, Thiago F; Boaventura, Maria Amelia D

    2011-01-01

    Auxins, such as indole-3-acetic acid (IAA), are important in plant germination and growth, while physiological polyamines, such as putrescine, are involved in cell proliferation and differentiation, and their concentrations increase during germination. In this work, novel indole amides were synthesized in good yields by monoacylation of morpholine and unprotected symmetrical diamines with indole-3-carboxylic acid, a putative metabolite of IAA, possessing no auxin-like activity. These amides were tested for their effects on seed germination and growth of the radicles and shoots of Lactuca sativa (lettuce) and Allium cepa (onion) seedlings, at 100.0, 1.0, and 0.01 microM concentrations. Germination was generally stimulated, with the exception of amide 3, derived from morpholine, at 100 microM. On radicle and shoot growth, the effect of these compounds was predominantly inhibitory. Compound 3 was the best inhibitor of growth of lettuce and onion, at the highest concentration. Amides, such as propanil, among others, are described as having herbicidal activity.

  19. Characterization of two tomato aquaporins and expression during the incompatible interaction of tomato with the plant parasite Cuscuta reflexa.

    Science.gov (United States)

    Werner, M; Uehlein, N; Proksch, P; Kaldenhoff, R

    2001-08-01

    A subtractive suppression hybridization technique was used to identify genes that were induced during early phases of the interaction between Cuscuta reflexa, a phanerogamic plant parasite and the incompatible host tomato (Lycopersicon esculentum Mill.). One of the identified genes encodes a new aquaporin (LeAqp2) from tomato. Its function was concluded from the swelling kinetics of LeAqp2-expressing Xenopus laevis oocytes under hypo-osmotic conditions. It was shown that, 6 h after attachment of the plant parasite, the corresponding mRNA accumulated in cells at and adjacent to the attachment site of Cuscuta, while artificial wounding did not modify steady-state LeAqp2- RNA levels. Expression of a close homologue named TRAMP (tomato-ripening-associated protein) was not affected by the plant-plant interaction. Levels of indole-3-acetic acid (IAA) in tomato tissue after infection by Cuscuta have been found to increase at a similar stage of infection. In contrast to the different behavior with respect to infection, IAA induced both LeAqp2 and TRAMP expression. The observed pattern of LeAqp2 expression during the interaction at a stage where cell elongation occurs together with the water-channel activity in the heterologous expression system suggest a function for LeAqp2 during the tomato-Cuscuta interaction.

  20. Changes induced by sodium cromoglycate on brain serotonin turnover in morphine dependent and abstinent mice.

    Science.gov (United States)

    San-Martin-Clark, O; Leza, J C; Lizasoain, I; Lorenzo, P

    1993-01-01

    This study was designed to explain the action of sodium cromoglycate (CRO) on the brain serotonergic system in control, morphine tolerant (by SC implantation of a 75 mg morphine pellet), and also in morphine dependent mice just before naloxone-precipitated withdrawal. After SC injections of CRO in control mice, morphine tolerant mice (day 4 of addiction), and 1 h before abstinence (withdrawal was induced by SC injection of 1 mg/kg naloxone on day 4 of addiction), animals were decapitated and various brain areas were rapidly removed. 5HT (Serotonin) and 5HIAA (5-hydroxyindole-3-acetic acid) were measured by high performance liquid chromatography coupled with electrochemical detection (HPLC-ECD). The ratio 5HIAA/5HT provided one index by which the turnover of the indoleamine was measured. CRO increased the turnover of 5HT in most of the brain areas studied in both control and morphine dependent mice. Furthermore, previous administration of CRO prior to naloxone challenge induced a significant increase in the 5HIAA/5HT ratio in the hypothalamus and striatum. These results are discussed as the reason for the preventive effect of CRO on jumping behaviour in morphine abstinent mice.