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Sample records for active gibberellin content

  1. Cryptochrome and Phytochrome Cooperatively but Independently Reduce Active Gibberellin Content in Rice Seedlings under Light Irradiation

    PubMed Central

    Hirose, Fumiaki; Inagaki, Noritoshi; Hanada, Atsushi; Yamaguchi, Shinjiro; Kamiya, Yuji; Miyao, Akio; Hirochika, Hirohiko; Takano, Makoto

    2012-01-01

    In contrast to a wealth of knowledge about the photoregulation of gibberellin metabolism in dicots, that in monocots remains largely unclear. In this study, we found that a blue light signal triggers reduction of active gibberellin content in rice seedlings with simultaneous repression of two gibberellin 20-oxidase genes (OsGA20ox2 and OsGA20ox4) and acute induction of four gibberellin 2-oxidase genes (OsGA2ox4–OsGA2ox7). For further examination of the regulation of these genes, we established a series of cryptochrome-deficient lines through reverse genetic screening from a Tos17 mutant population and construction of knockdown lines based on an RNA interference technique. By using these lines and phytochrome mutants, we elucidated that cryptochrome 1 (cry1), consisting of two species in rice plants (cry1a and cry1b), is indispensable for robust induction of the GA2ox genes. On the other hand, repression of the GA20ox genes is mediated by phytochromes. In addition, we found that the phytochromes also mediate the repression of a gibberellin 3-oxidase gene (OsGA3ox2) in the light. These results imply that, in rice seedlings, phytochromes mediate the repression of gibberellin biosynthesis capacity, while cry1 mediates the induction of gibberellin inactivation capacity. The cry1 action was demonstrated to be dominant in the reduction of active gibberellin content, but, in rice seedlings, the cumulative effects of these independent actions reduced active gibberellin content in the light. This pathway design in which different types of photoreceptors independently but cooperatively regulate active gibberellin content is unique from the viewpoint of dicot research. This redundancy should provide robustness to the response in rice plants. PMID:22764280

  2. Germination of photoblastic lettuce seeds is regulated via the control of endogenous physiologically active gibberellin content, rather than of gibberellin responsiveness

    PubMed Central

    Sawada, Yoshiaki; Katsumata, Takumi; Kitamura, Jun; Kawaide, Hiroshi; Nakajima, Masatoshi; Asami, Tadao; Nakaminami, Kentaro; Kurahashi, Toshihiro; Mitsuhashi, Wataru; Inoue, Yasunori; Toyomasu, Tomonobu

    2008-01-01

    Phytochrome regulates lettuce (Lactuca sativa L. cv. Grand Rapids) seed germination via the control of the endogenous level of bioactive gibberellin (GA). In addition to the previously identified LsGA20ox1, LsGA20ox2, LsGA3ox1, LsGA3ox2, LsGA2ox1, and LsGA2ox2, five cDNAs were isolated from lettuce seeds: LsCPS, LsKS, LsKO1, LsKO2, and LsKAO. Using an Escherichia coli expression system and functional assays, it is shown that LsCPS and LsKS encode ent-copalyl diphosphate synthase and ent-kaurene synthase, respectively. Using a Pichia pastoris system, it was found that LsKO1 and LsKO2 encode ent-kaurene oxidases and LsKAO encodes ent-kaurenoic acid oxidase. A comprehensive expression analysis of GA metabolism genes using the quantitative reverse transcription polymerase chain reaction suggested that transcripts of LsGA3ox1 and LsGA3ox2, both of which encode GA 3-oxidase for GA activation, were primarily expressed in the hypocotyl end of lettuce seeds, were expressed at much lower levels than the other genes tested, and were potently up-regulated by phytochrome. Furthermore, LsDELLA1 and LsDELLA2 cDNAs that encode DELLA proteins, which act as negative regulators in the GA signalling pathway, were isolated from lettuce seeds. The transcript levels of these two genes were little affected by light. Lettuce seeds in which de novo GA biosynthesis was suppressed responded almost identically to exogenously applied GA, irrespective of the light conditions, suggesting that GA responsiveness is not significantly affected by light in lettuce seeds. It is proposed that lettuce seed germination is regulated mainly via the control of the endogenous content of bioactive GA, rather than the control of GA responsiveness. PMID:18653696

  3. Cytosolic activity of the gibberellin receptor GIBBERELLIN INSENSITIVE DWARF1A.

    PubMed

    Livne, Sivan; Weiss, David

    2014-10-01

    Arabidopsis has three gibberellin receptors, GIBBERELLIN INSENSITIVE DWARF1 A (GID1A), GID1B and GID1C. All GID1s are localized to the nucleus but have also been detected in the cytoplasm. Since other major gibberellin signaling components have been localized to the nucleus, the current model suggests that gibberellin perception and signaling is nuclear. In this work we investigated whether GID1A can perceive gibberellin and initiate a signaling cascade in the cytosol. We have generated transgenic plants expressing GID1A fused to green florescence protein (GFP) and either a nuclear export signal (NES) or a nuclear localization signal (NLS), in the background of the gid1a gid1c (gid1ac) double mutant. Analyses by confocal microscopy confirmed the localization of GFP-GID1A-NES only in the cytosol and of GFP-GID1A-NLS only in the nucleus. Surprisingly, both recombinant proteins were able to complement the gid1ac mutation and to restore growth and responsiveness to gibberellin. However, transgenic seeds and seedlings expressing GFP-GID1A-NLS were more sensitive to gibberellin than those expressing GFP-GID1A-NES. The results of this study suggest that GID1A can bind gibberellin in the cytosol to initiate gibberellin signaling and responses. It is possible that activated cytosolic GID1A interacts with DELLA proteins before they enter the nucleus and induces a conformational transition that leads to DELLA's deactivation or degradation in the nucleus.

  4. Aloe vera and gibberellin. Anti-inflammatory activity in diabetes.

    PubMed

    Davis, R H; Maro, N P

    1989-01-01

    Aloe vera inhibits inflammation and adjuvant-induced arthritis. The authors' laboratory has shown that A. vera improves wound healing, which suggests that it does not act like an adrenal steroid. Diabetic animals were used in this study because of their poor wound healing and anti-inflammatory capabilities. The anti-inflammatory activity of A. vera and gibberellin was measured in streptozotocin-induced diabetic mice by measuring the inhibition of polymorphonuclear leukocyte infiltration into a site of gelatin-induced inflammation over a dose range of 2 to 100 mg/kg. Both Aloe and gibberellin similarly inhibited inflammation in a dose-response manner. These data tend to suggest that gibberellin or a gibberellin-like substance is an active anti-inflammatory component in A. vera.

  5. Biological activity of some conjugated gibberellins.

    PubMed

    Sembdner, G; Borgmann, E; Schneider, G; Liebisch, H W; Miersch, O; Adam, G; Lischewski, M; Schrefber, K

    1976-01-01

    The biological activity of several gibberellin (GA) conjugates was studied and compared with that of the corresponding free GAs. The following conjugates were included: O(3)-β-D-glucopyranosides of GA1, GA3 and GA4; O(13)-β-D-glucopyranosides of GA1, GA3 and GA5; O(13)-β-D-glucopyranosyl-GA5-β-D-glucopyranosyl ester; GA3-β-D-glucopyranosyl ester and GA3-α-D-glucopyranosyl ester; N-GA3-oyl-glycine, its methyl ester, N-GA3-oyl-glycylglycine, and N-GA3-oyl-proline. All compounds were synthesized chemically but some of them are known to occur as endogenous plant products, or to be formed in plants upon application of a free GA. Activity was determined in the dwarf pea, dwarf corn, dwarf rice, and lettuce hypocotyl bioassays. The GA conjugates were found to posses different relative activities depending on the chemical structure, the bioassay system, and the site of application (shoot or roots). It is concluded that the activity of GA conjugates as measured in different bioassays is based upon the ability of plant enzymes and possibly of certain microorganisms to hydrolyze glucosidic, glucosyl ester, and amide-like linkages.

  6. Comparison of Biological Activities of Gibberellins and Gibberellin-Precursors Native to Thlaspi arvense L. 1

    PubMed Central

    Metzger, James D.

    1990-01-01

    Field pennycress (Thlaspi arvense L.) is a winter annual weed with a cold requirement for stem elongation and flowering. The relative abilities of several native gibberellins (GAs) and GA-precursors to elicit stem growth were compared. Of the eight compounds tested, gibberellin A1, (GA1), GA9, and GA20 caused stem growth in noninduced (no cold treatment) plants. No stem growth was observed in plants treated with ent-kaurene, ent-kaurenol, ent-kaurenoic acid, GA53, or GA8. Moreover, of the biologically active compounds, GA9 was the most active followed closely by GA1. In thermoinduced plants (4-week cold treatment at 6°C) that were continuously treated with 2-chlorocholine chloride to reduce endogenous GA production, GA9 was the most biologically active compound. However, the three kaurenoid GA precursors also promoted stem growth in thermoinduced plants, and were almost as active as GA20. No such increase in activity was observed for either GA[unk] or GA53. The results are discussed in relation to thermoinductive regulation of GA metabolism and its significance to the initiation of stem growth in field pennycress. It is proposed that thermoinduction results in increased conversion of ent-kaurenoic acid to GAs through the C-13 desoxy pathway and that GA9 is the endogenous mediator of thermoinduced stem growth in field pennycress. PMID:16667681

  7. Reduction of the Gibberellin Content of Pharbitis Seeds by CCC and After-Effects in the Progeny.

    PubMed

    Zeevaart, J A

    1966-05-01

    Plants of Pharbitis nil were treated with the growth retardant (2-chloroethyl) trimethylammonium chloride (CCC) shortly before and after anthesis. Fresh and dry weight of immature seeds were not affected by the CCC treatment.The level of gibberellin-like activity in Pharbitis seeds as compared to control seeds was strongly reduced by CCC application. The progenies of the treated plants also had a much reduced GA content in the seedling stage. These results are interpreted to indicate that CCC blocks gibberellin biosynthesis in higher plants, as it does in the fungus Fusarium.CCC applied via the roots accumulated in the immature seeds and was carried over to the following generation. Consequently, growth of CCC progenies was dwarfed and flower formation inhibited. Both phenomena were overcome by application of gibberellin A(3).Three gibberellin-like substances (called fractions I, II, and III) were present in Pharbitis seeds and could be separated by thin-layer chromatography. All 3 fractions were also present in seeds treated with CCC. Fractions II and III were present in much higher quantities than fraction I. Both fractions II and III promoted growth of d5 corn but only fraction II was active in dwarf peas grown under red light.

  8. Heterosis in rice seedlings: its relationship to gibberellin content and expression of gibberellin metabolism and signaling genes.

    PubMed

    Ma, Qian; Hedden, Peter; Zhang, Qifa

    2011-08-01

    Despite the accumulation of data on the genetic and molecular understanding of heterosis, there is little information on the regulation of heterosis at the physiological level. In this study, we performed a quantitative analysis of endogenous gibberellin (GA) content and expression profiling of the GA metabolism and signaling genes to investigate the possible relationship between GA signaling and heterosis for seedling development in rice (Oryza sativa). The materials used were an incomplete diallele set of 3 × 3 crosses and the six parents. In the growing shoots of the seedlings at 20 d after sowing, significant positive correlations between the contents of some GA species and performance and heterosis based on shoot dry mass were detected. Expression analyses of GA-related genes by real-time reverse transcription-polymerase chain reaction revealed that 13 out of the 16 GA-related genes examined exhibited significant differential expression among the F1 hybrid and its parents, acting predominantly in the modes of overdominance and positive dominance. Expression levels of nine genes in the hybrids displayed significant positive correlations with the heterosis of shoot dry mass. These results imply that GAs play a positive role in the regulation of heterosis for rice seedling development. In shoots plus root axes of 4-d-old germinating seeds that had undergone the deetiolation, mimicking normal germination in soil, the axis dry mass was positively correlated with the content of GA₂₉ but negatively correlated with that of GA₁₉. Our findings provide supporting evidence for GAs playing an important regulatory role in heterosis for rice seedling development.

  9. Wounding induces changes in cytokinin and auxin content in potato tuber, but does not induce formation of gibberellins.

    PubMed

    Lulai, Edward C; Suttle, Jeffrey C; Olson, Linda L; Neubauer, Jonathan D; Campbell, Larry G; Campbell, Michael A

    2016-02-01

    Cytokinin, auxin and gibberellin contents in resting and wound-responding potato tubers have not been fully determined and coordinated with wound-healing processes. Using a well-defined wound-healing model system, hormone content and expression of genes associated with hormone turnover were determined in tubers following wounding. Changes in hormone content were coordinated with: (I) formation and completion of the wound closing layer (0-5/6 days), and (II) initiation of phellogen and wound periderm formation (∼ 7 days). Quantifiable amounts of biologically active cytokinins (Z, DZ and IP) were not detected in resting or wound-responding tubers. However, the precursor IPA and catabolic product c-ZOG were found in small amounts in resting and wound-responding tubers. Wound-induced activation of cytokinin biosynthesis was suggested by an increase in t-ZR and c-ZR content at 0.5 days and large increases in IPA and c-ZR content by 3 days and throughout 7 days after wounding suggesting roles in II, but little or no role in I. Expression of key genes involved in cytokinin metabolism followed similar profiles with transcripts decreasing through 3 days and then increasing at 5-7 days after wounding. Both free IAA and IAA-Asp were present in resting tubers. While IAA-Asp was no longer present by 3 days after wounding, IAA content nearly doubled by 5 days and was more than 4-fold greater at 7 days compared to that in resting tuber (0 day) suggesting roles in II, but little or no role in I. Gibberellins were not present in quantifiable amounts in resting or wound-responding tubers. These results suggest that bio-active cytokinins are wound-induced, but their residency is temporal and highly regulated. The transient presence of active cytokinins and corresponding increases in IAA content strongly suggest their involvement in the regulation of wound periderm development. The absence of gibberellins indicates that they are not a regulatory component of wound-healing processes.

  10. The gene pat-2, which induces natural parthenocarpy, alters the gibberellin content in unpollinated tomato ovaries.

    PubMed

    Fos, M; Nuez, F; García-Martínez, J L

    2000-02-01

    We investigated the role of gibberellins (GAs) in the effect of pat-2, a recessive mutation that induces facultative parthenocarpic fruit development in tomato (Lycopersicon esculentum Mill.) using near-isogenic lines with two different genetic backgrounds. Unpollinated wild-type Madrigal (MA/wt) and Cuarenteno (CU/wt) ovaries degenerated, but GA(3) application induced parthenocarpic fruit growth. On the contrary, parthenocarpic growth of MA/pat-2 and CU/pat-2 fruits, which occurs in the absence of pollination and hormone application, was not affected by GA(3). Pollinated MA/wt and parthenocarpic MA/pat-2 ovary development was negated by paclobutrazol, and this inhibitory effect was counteracted by GA(3). The main GAs of the early-13-hydroxylation pathway (GA(1), GA(3), GA(8), GA(19), GA(20), GA(29), GA(44), GA(53), and, tentatively, GA(81)) and two GAs of the non-13-hydroxylation pathway (GA(9) and GA(34)) were identified in MA/wt ovaries by gas chromatography-selected ion monitoring. GAs were quantified in unpollinated ovaries at flower bud, pre-anthesis, and anthesis. In unpollinated MA/pat-2 and CU/pat-2 ovaries, the GA(20) content was much higher (up to 160 times higher) and the GA(19) content was lower than in the corresponding non-parthenocarpic ovaries. The application of an inhibitor of 2-oxoglutarate-dependent dioxygenases suggested that GA(20) is not active per se. The pat-2 mutation may increase GA 20-oxidase activity in unpollinated ovaries, leading to a higher synthesis of GA(20), the precursor of an active GA.

  11. Gibberellin-like activity in suspensors of Tropaeolum majus L. and Cytisus laburnum L.

    PubMed

    Picciarelli, P; Alpi, A; Pistelli, L; Scalet, M

    1984-12-01

    Gibberellins in the embryo-suspensor system have been considered so far only in Phaseolus coccineus. We present in this report the localization of gibberellin-like substances in the suspensors of Tropaeolum majus L. and Cytisus laburnum L. The total gibberellin activity (expressed as gibberellic-acid equivalent in the α-amylase bioassay) in 2000 suspensors (106 mg fresh weight; FW) of C. laburnum and in 600 suspensors (236 mg FW) of T. majus were 50.9 μg g(-1) FW and 8.9 μg g(-1) FW respectively.

  12. Ethylene-mediated regulation of gibberellin content and growth in helianthus annuus L

    SciTech Connect

    Pearce, D.W.; Reid, D.M.; Pharis, R.P. )

    1991-04-01

    Elongation of hypocotyls of sunflower can be promoted by gibberellins (GAs) and inhibited by ethylene. The role of these hormones in regulating elongation was investigated by measuring changes in both endogenous GAs and in the metabolism of exogenous ({sup 3}H)- and ({sup 2}H{sub 2})GA{sub 20} in the hypocotyls of sunflower (Helianthus annuus L. cv Delgren 131) seedlings exposed to ethylene. The major biologically active GAs identified by gas chromatography-mass spectrometry were GA{sub 1}, GA{sub 19}, GA{sub 20}, and GA{sub 44}. In hypocotyls of seedlings exposed to ethylene, the concentration of GA{sub 1}, known to be directly active in regulating shoot elongation in a number of species, was reduced. Ethylene treatment reduced the metabolism of ({sup 3}H)GA{sub 20} and less ({sup 2}H{sub 2})GA{sub 1} was found in the hypocotyls of those seedlings exposed to the higher ethylene concentrations. However, it is not known if the effect of ethylene on GA{sub 20} metabolism was direct or indirect. In seedlings treated with exogenous GA{sub 1} or GA{sub 3}, the hypocotyls elongated faster than those of controls, but the GA treatment only partially overcame the inhibitory effect of ethylene on elongation. The authors conclude that GA content is a factor which may limit elongation in hypocotyls of sunflower, and that while exposure to ethylene results in reduced concentration of GA{sub 1} this is not sufficient per se to account for the inhibition of elongation caused by ethylene.

  13. Increased gibberellin contents contribute to accelerated growth and development of transgenic tobacco overexpressing a wheat ubiquitin gene.

    PubMed

    Wang, Guo-Kun; Zhang, Meng; Gong, Jiang-Feng; Guo, Qi-Fang; Feng, Ya-Nan; Wang, Wei

    2012-12-01

    Overexpressing TaUb2 promoted stem growth and resulted in early flowering in transgenic tobacco plants. Ubiquitin are involved in the production, metabolism and proper function of gibberellin. The ubiquitin-26S proteasome system (UPS), in which ubiquitin (Ub) functions as a marker, is a post-translational regulatory system that plays a prominent role in various biological processes. To investigate the impact of different Ub levels on plant growth and development, transgenic tobacco (Nicotiana tabacum L.) plants were engineered to express an Ub gene (TaUb2) from wheat (Triticum aestivum L.) under the control of cauliflower mosaic virus 35S promoter. Transgenic tobacco plants overexpressing TaUb2 demonstrated an accelerated growth rate at early stage and an early flowering phenotype in development. The preceding expression of MADS-box genes also corresponded to the accelerated developmental phenotypes of the transgenic tobacco plants compared to that of wild-type (WT). Total gibberellin (GA) and active GA contents in transgenic tobacco plants were higher than those in WT at the corresponding developmental stages, and some GA metabolism genes were upregulated. Treatment with GA(3) conferred a similarly accelerated grown rate in WT plants to that of transgenic tobacco plants, while growth was inhibited when transgenic tobacco plants were treated with a GA biosynthesis inhibitor. Thus, the results suggest that Ub are involved in the production, metabolism and proper function of GA, which is important in the regulation of plant growth and development.

  14. Wounding induces changes in cytokinin and auxin content in potato tuber, but does not induce formation of gibberellins

    USDA-ARS?s Scientific Manuscript database

    Cytokinin, auxin and gibberellin content in resting and wound-responding potato tuber are not clearly defined. Consequently, the coordination and possible networking of these classical hormones in the regulation of wound-healing processes are poorly understood. Using a well-defined tuber wound-hea...

  15. Hormone profiles in microalgae: gibberellins and brassinosteroids.

    PubMed

    Stirk, W A; Bálint, P; Tarkowská, D; Novák, O; Strnad, M; Ördög, V; van Staden, J

    2013-09-01

    Endogenous gibberellins and brassinosteroids were quantified in 24 axenic microalgae strains from the Chlorophyceae, Trebouxiophyceae, Ulvophyceae and Charophyceae microalgae strains after 4 days in culture. This is the first report of endogenous gibberellins being successfully detected in microalgae. Between 18 and 20 gibberellins were quantified in all strains with concentrations ranging from 342.7 pg mg(-1) DW in Raphidocelis subcapitata MACC 317-4746.1 pg mg(-)(1) DW in Scotiellopsis terrestris MACC 44. Slower growing strains (S. terrestris MACC 44, Gyoerffyana humicola MACC 334, Nautococcus mamillatus MACC 716 and Chlorococcum ellipsoideum MACC 712) exhibited the highest gibberellin contents while lowest levels of gibberellins were found in faster growing strains (R. subcapitata MACC 317 and Coelastrum excentrica MACC 504). In all strains, the active gibberellin detected in the highest concentration was GA6, the predominant intermediates were GA15 and GA53 and the main biosynthetic end products were GA13 and GA51. Gibberellin profiles were similar in all strains except for the presence/absence of GA12 and GA12ald. To date this is the second report of endogenous brassinosteroids in microalgae. Brassinosteroids were detected in all 24 strains with concentrations ranging from 117.3 pg mg(-)(1) DW in R. subcapitata MACC 317-977.8 pg mg(-)(1) DW in Klebsormidium flaccidum MACC 692. Two brassinosteroids, brassinolide and castasterone were determined in all the strains. Generally, brassinolide occurred in higher concentrations than castasterone.

  16. Temperature Regulation of Endogenous Gibberellin Activity and Development of Tulipa gesneriana L. 1

    PubMed Central

    Aung, L. H.; De Hertogh, A. A.; Staby, G.

    1969-01-01

    The changes in the contents of free and bound gibberellin-like activity (GA) of Tulipa gesneriana L. cv. Ralph during development under 2 temperature conditions were studied. The results show that the content of free GA of bulbs grown at 18° increased by 67% over the initial level during development. The bound GA showed a slight initial increase and was followed by a rapid decrease. In contrast, bulbs treated at 13° showed a marked decline in free GA and a 2-fold increase in the content of bound GA. However, after the transfer of these bulbs from 13° to 18° the free GA increased to the initial level while the bound GA decreased to a low level. The rate of floral shoot and root development and time of flowering were accelerated at 18° as compared to 13°. From the data obtained, it was suggested that a temperature-sensitive interconversion mechanism between free and bound GA exists in tulip bulbs and that there is apparent synthesis or transformation of these phytohormones during development of the bulbs. PMID:16657075

  17. The Gene pat-2, Which Induces Natural Parthenocarpy, Alters the Gibberellin Content in Unpollinated Tomato Ovaries1

    PubMed Central

    Fos, Mariano; Nuez, Fernando; García-Martínez, José L.

    2000-01-01

    We investigated the role of gibberellins (GAs) in the effect of pat-2, a recessive mutation that induces facultative parthenocarpic fruit development in tomato (Lycopersicon esculentum Mill.) using near-isogenic lines with two different genetic backgrounds. Unpollinated wild-type Madrigal (MA/wt) and Cuarenteno (CU/wt) ovaries degenerated, but GA3 application induced parthenocarpic fruit growth. On the contrary, parthenocarpic growth of MA/pat-2 and CU/pat-2 fruits, which occurs in the absence of pollination and hormone application, was not affected by GA3. Pollinated MA/wt and parthenocarpic MA/pat-2 ovary development was negated by paclobutrazol, and this inhibitory effect was counteracted by GA3. The main GAs of the early-13-hydroxylation pathway (GA1, GA3, GA8, GA19, GA20, GA29, GA44, GA53, and, tentatively, GA81) and two GAs of the non-13-hydroxylation pathway (GA9 and GA34) were identified in MA/wt ovaries by gas chromatography-selected ion monitoring. GAs were quantified in unpollinated ovaries at flower bud, pre-anthesis, and anthesis. In unpollinated MA/pat-2 and CU/pat-2 ovaries, the GA20 content was much higher (up to 160 times higher) and the GA19 content was lower than in the corresponding non-parthenocarpic ovaries. The application of an inhibitor of 2-oxoglutarate-dependent dioxygenases suggested that GA20 is not active per se. The pat-2 mutation may increase GA 20-oxidase activity in unpollinated ovaries, leading to a higher synthesis of GA20, the precursor of an active GA. PMID:10677440

  18. Heterosis in Rice Seedlings: Its Relationship to Gibberellin Content and Expression of Gibberellin Metabolism and Signaling Genes1[W][OA

    PubMed Central

    Ma (马谦), Qian; Hedden, Peter; Zhang (张启发), Qifa

    2011-01-01

    Despite the accumulation of data on the genetic and molecular understanding of heterosis, there is little information on the regulation of heterosis at the physiological level. In this study, we performed a quantitative analysis of endogenous gibberellin (GA) content and expression profiling of the GA metabolism and signaling genes to investigate the possible relationship between GA signaling and heterosis for seedling development in rice (Oryza sativa). The materials used were an incomplete diallele set of 3 × 3 crosses and the six parents. In the growing shoots of the seedlings at 20 d after sowing, significant positive correlations between the contents of some GA species and performance and heterosis based on shoot dry mass were detected. Expression analyses of GA-related genes by real-time reverse transcription-polymerase chain reaction revealed that 13 out of the 16 GA-related genes examined exhibited significant differential expression among the F1 hybrid and its parents, acting predominantly in the modes of overdominance and positive dominance. Expression levels of nine genes in the hybrids displayed significant positive correlations with the heterosis of shoot dry mass. These results imply that GAs play a positive role in the regulation of heterosis for rice seedling development. In shoots plus root axes of 4-d-old germinating seeds that had undergone the deetiolation, mimicking normal germination in soil, the axis dry mass was positively correlated with the content of GA29 but negatively correlated with that of GA19. Our findings provide supporting evidence for GAs playing an important regulatory role in heterosis for rice seedling development. PMID:21693671

  19. Gibberellin Perception by the Gibberellin Receptor and its Effector Recognition

    NASA Astrophysics Data System (ADS)

    Hakoshima, Toshio; Murase, Kohji; Hirano, Yoshinori; Sun, Tai-Ping

    Gibberellins control a diverse range of growth and developmental processes in higher plants and have been widely utilized in the agricultural industry. By binding to a nuclear receptor GIBBERELLIN INSENSITIVE DWARF1 (GID1), gibberellins regulate gene expression by promoting degradation of the transcriptional regulator DELLA proteins. The precise manner in which GID1 discriminates and becomes activated by bioactive gibberellins for specific binding to DELLA proteins remains unclear. We present the crystal structure of a ternary complex of Arabidopsis thaliana GID1A, a bioactive gibberellin and the N-terminal DELLA domain of GAI. In this complex, GID1a occludes gibberellin in a deep binding pocket covered by its N-terminal helical switch region, which in turn interacts with the DELLA domain containing DELLA, VHYNP and LExLE motifs. Our results establish a structural model of a plant hormone receptor which is distinct from the hormone-perception mechanism and effector recognition of the known auxin receptors.

  20. Expression of gibberellin 3 beta-hydroxylase gene in a gravi-response mutant, weeping Japanese flowering cherry

    NASA Technical Reports Server (NTRS)

    Sugano, Mami; Nakagawa, Yuriko; Nyunoya, Hiroshi; Nakamura, Teruko

    2004-01-01

    Expressions of the gibberellin biosynthesis gene were investigated in a normal upright type and a gravi-response mutant, a weeping type of Japanese flowering cherry (Prunus spachiana), that is unable to support its own weight and elongates downward. A segment of the gibberellin 3 beta-hydroxylase cDNA of Prunus spachiana (Ps3ox), which is responsible for active gibberellin synthesis, was amplified by using real-time RT-PCR. The content of Ps3ox mRNA in the weeping type was much greater than that in the upright type, while the endogenous gibberellin level was much higher in the elongating zone of the weeping type. These results suggest that the amount and distribution of synthesized gibberellin regulate secondary xylem formation, and the unbalanced distribution of gibberellin affects the gravi-response of the Prunus tree.

  1. Expression of gibberellin 3 beta-hydroxylase gene in a gravi-response mutant, weeping Japanese flowering cherry

    NASA Technical Reports Server (NTRS)

    Sugano, Mami; Nakagawa, Yuriko; Nyunoya, Hiroshi; Nakamura, Teruko

    2004-01-01

    Expressions of the gibberellin biosynthesis gene were investigated in a normal upright type and a gravi-response mutant, a weeping type of Japanese flowering cherry (Prunus spachiana), that is unable to support its own weight and elongates downward. A segment of the gibberellin 3 beta-hydroxylase cDNA of Prunus spachiana (Ps3ox), which is responsible for active gibberellin synthesis, was amplified by using real-time RT-PCR. The content of Ps3ox mRNA in the weeping type was much greater than that in the upright type, while the endogenous gibberellin level was much higher in the elongating zone of the weeping type. These results suggest that the amount and distribution of synthesized gibberellin regulate secondary xylem formation, and the unbalanced distribution of gibberellin affects the gravi-response of the Prunus tree.

  2. Rapid and reproducible determination of active gibberellins in citrus tissues by UPLC/ESI-MS/MS.

    PubMed

    Manzi, Matías; Gómez-Cadenas, Aurelio; Arbona, Vicent

    2015-09-01

    Phytohormone determination is crucial to explain the physiological mechanisms during growth and development. Therefore, rapid and precise methods are needed to achieve reproducible determination of phytohormones. Among many others, gibberellins (GAs) constitute a family of complex analytes as most of them share similar structure and chemical properties although only a few hold biological activity (namely GA1; GA3; GA4 and GA7). A method has been developed to extract GAs from plant tissues by mechanical disruption using ultrapure water as solvent and, in this way, ion suppression was reduced whereas sensitivity increased. Using this methodology, the four active GAs were separated and quantified by UPLC coupled to MS/MS using the isotope-labeled internal standards [(2)H2]-GA1 and [(2)H2]-GA4. To sum up, the new method provides a fast and reproducible protocol to determine bioactive GAs at low concentrations, using minimal amounts of sample and reducing the use of organic solvents.

  3. An A20/AN1-type zinc finger protein modulates gibberellins and abscisic acid contents and increases sensitivity to abiotic stress in rice (Oryza sativa).

    PubMed

    Zhang, Ye; Lan, Hongxia; Shao, Qiaolin; Wang, Ruqin; Chen, Hui; Tang, Haijuan; Zhang, Hongsheng; Huang, Ji

    2016-01-01

    The plant hormones gibberellins (GA) and abscisic acid (ABA) play important roles in plant development and stress responses. Here we report a novel A20/AN1-type zinc finger protein ZFP185 involved in GA and ABA signaling in the regulation of growth and stress response. ZFP185 was constitutively expressed in various rice tissues. Overexpression of ZFP185 in rice results in a semi-dwarfism phenotype, reduced cell size, and the decrease of endogenous GA3 content. By contrast, higher GA3 content was observed in RNAi plants. The application of exogenous GA3 can fully rescue the semi-dwarfism phenotype of ZFP185 overexpressing plants, suggesting the negative role of ZFP185 in GA biosynthesis. Besides GA, overexpression of ZFP185 decreased ABA content and expression of several ABA biosynthesis-related genes. Moreover, it was found that ZFP185, unlike previously known A20/AN1-type zinc finger genes, increases sensitivity to drought, cold, and salt stresses, implying the negative role of ZFP185 in stress tolerance. ZFP185 was localized in the cytoplasm and lacked transcriptional activation potential. Our study suggests that ZFP185 regulates plant growth and stress responses by affecting GA and ABA biosynthesis in rice.

  4. The Arabidopsis gibberellin methyl transferase 1 suppresses gibberellin activity, reduces whole-plant transpiration and promotes drought tolerance in transgenic tomato.

    PubMed

    Nir, Ido; Moshelion, Menachem; Weiss, David

    2014-01-01

    Previous studies have shown that reduced gibberellin (GA) level or signal promotes plant tolerance to environmental stresses, including drought, but the underlying mechanism is not yet clear. Here we studied the effects of reduced levels of active GAs on tomato (Solanum lycopersicum) plant tolerance to drought as well as the mechanism responsible for these effects. To reduce the levels of active GAs, we generated transgenic tomato overexpressing the Arabidopsis thaliana GA METHYL TRANSFERASE 1 (AtGAMT1) gene. AtGAMT1 encodes an enzyme that catalyses the methylation of active GAs to generate inactive GA methyl esters. Tomato plants overexpressing AtGAMT1 exhibited typical GA-deficiency phenotypes and increased tolerance to drought stress. GA application to the transgenic plants restored normal growth and sensitivity to drought. The transgenic plants maintained high leaf water status under drought conditions, because of reduced whole-plant transpiration. The reduced transpiration can be attributed to reduced stomatal conductance. GAMT1 overexpression inhibited the expansion of leaf-epidermal cells, leading to the formation of smaller stomata with reduced stomatal pores. It is possible that under drought conditions, plants with reduced GA activity and therefore, reduced transpiration, will suffer less from leaf desiccation, thereby maintaining higher capabilities and recovery rates.

  5. The ERF11 Transcription Factor Promotes Internode Elongation by Activating Gibberellin Biosynthesis and Signaling1[OPEN

    PubMed Central

    Zhou, Xin; Zhang, Zhong-Lin; Tyler, Ludmila; Yusuke, Jikumaru; Qiu, Kai; Lumba, Shelley; Desveaux, Darrell; McCourt, Peter; Sun, Tai-ping

    2016-01-01

    The phytohormone gibberellin (GA) plays a key role in promoting stem elongation in plants. Previous studies show that GA activates its signaling pathway by inducing rapid degradation of DELLA proteins, GA signaling repressors. Using an activation-tagging screen in a reduced-GA mutant ga1-6 background, we identified AtERF11 to be a novel positive regulator of both GA biosynthesis and GA signaling for internode elongation. Overexpression of AtERF11 partially rescued the dwarf phenotype of ga1-6. AtERF11 is a member of the ERF (ETHYLENE RESPONSE FACTOR) subfamily VIII-B-1a of ERF/AP2 transcription factors in Arabidopsis (Arabidopsis thaliana). Overexpression of AtERF11 resulted in elevated bioactive GA levels by up-regulating expression of GA3ox1 and GA20ox genes. Hypocotyl elongation assays further showed that overexpression of AtERF11 conferred elevated GA response, whereas loss-of-function erf11 and erf11 erf4 mutants displayed reduced GA response. In addition, yeast two-hybrid, coimmunoprecipitation, and transient expression assays showed that AtERF11 enhances GA signaling by antagonizing the function of DELLA proteins via direct protein-protein interaction. Interestingly, AtERF11 overexpression also caused a reduction in the levels of another phytohormone ethylene in the growing stem, consistent with recent finding showing that AtERF11 represses transcription of ethylene biosynthesis ACS genes. The effect of AtERF11 on promoting GA biosynthesis gene expression is likely via its repressive function on ethylene biosynthesis. These results suggest that AtERF11 plays a dual role in promoting internode elongation by inhibiting ethylene biosynthesis and activating GA biosynthesis and signaling pathways. PMID:27255484

  6. Physiological Studies of a Synthetic Gibberellin-Like Bioregulator: II. Effect of Site of Application on Biological Activity.

    PubMed

    Suttle, J C; Hultstrand, J F

    1987-08-01

    The biological activity of the synthetic gibberellin agonist AC-94,377 (1-[3-chlorophthalimido]-cyclohexanecarboxamide) in certain plants is strictly dependent on the site of application. Root application of AC-94,377 at concentrations greater than or equal to 1 micromolar to seedlings of dwarf corn (Zea mays L. var d(5)), dwarf rice (Oryza sativa L. cv Tan-ginbozu), and sunflower (Helianthus annuus L. cv NK265) seedlings resulted in readily measurable gibberellin-like biological activity. Application of up to 10 micrograms of AC-94,377 to the shoots of these same species had no effect. AC-94,377 was metabolized to more polar products in both dwarf corn and sunflower seedlings. After 4 days of continuous root treatment with [(14)C]AC-94,377, greater than 70% of the recovered (14)C was found in the form of unmetabolized AC-94,377. In contrast, only 30 to 40% of the recovered (14)C was unmetabolized 4 days after shoot treatment. Translocation studies demonstrated that the movement of [(14)C]AC-94,377 was limited and occurred almost exclusively in an apoplastic fashion. Four days after leaf treatment, less than 1.5% (corn) or 4% (sunflower) of the recovered radioactivity had moved away from the treated area. It was concluded that the lack of biological activity of AC-94,377 following shoot treatment resulted principally from limited phloem mobility and to a lesser extent from accelerated metabolic breakdown.

  7. Reactivation of meristem activity and sprout growth in potato tubers require both cytokinin and gibberellin.

    PubMed

    Hartmann, Anja; Senning, Melanie; Hedden, Peter; Sonnewald, Uwe; Sonnewald, Sophia

    2011-02-01

    Reactivation of dormant meristems is of central importance for plant fitness and survival. Due to their large meristem size, potato (Solanum tuberosum) tubers serve as a model system to study the underlying molecular processes. The phytohormones cytokinins (CK) and gibberellins (GA) play important roles in releasing potato tuber dormancy and promoting sprouting, but their mode of action in these processes is still obscure. Here, we established an in vitro assay using excised tuber buds to study the dormancy-releasing capacity of GA and CK and show that application of gibberellic acid (GA(3)) is sufficient to induce sprouting. In contrast, treatment with 6-benzylaminopurine induced bud break but did not support further sprout growth unless GA(3) was administered additionally. Transgenic potato plants expressing Arabidopsis (Arabidopsis thaliana) GA 20-oxidase or GA 2-oxidase to modify endogenous GA levels showed the expected phenotypical changes as well as slight effects on tuber sprouting. The isopentenyltransferase (IPT) from Agrobacterium tumefaciens and the Arabidopsis cytokinin oxidase/dehydrogenase1 (CKX) were exploited to modify the amounts of CK in transgenic potato plants. IPT expression promoted earlier sprouting in vitro. Strikingly, CKX-expressing tubers exhibited a prolonged dormancy period and did not respond to GA(3). This supports an essential role of CK in terminating tuber dormancy and indicates that GA is not sufficient to break dormancy in the absence of CK. GA(3)-treated wild-type and CKX-expressing tuber buds were subjected to a transcriptome analysis that revealed transcriptional changes in several functional groups, including cell wall metabolism, cell cycle, and auxin and ethylene signaling, denoting events associated with the reactivation of dormant meristems.

  8. Gibberellin Receptor GID1: Gibberellin Recognition and Molecular Evolution

    NASA Astrophysics Data System (ADS)

    Kato, Hiroaki; Sato, Tomomi; Ueguchi-Tanaka, Miyako

    Gibberellins (GAs) are phytohormones essential for many developmental processes in plants. We analyzed the crystal structure of a nuclear GA receptor, GIBBERELLIN INSENSITIVE DWARF 1 (GID1) from Oryza sativa. As it was proposed from the sequence similarity, the overall structure of GID1 shows an α/β-hydrolase fold similar to that of the hormone-sensitive lipases (HSLs) except for an amino-terminal lid. The GA-binding site corresponds to the substrate-binding site of HSLs. Almost residues assigned for GA binding showed very little or no activity when they were replaced with Ala. The substitution of the residues corresponding to those of the lycophyte GID1s caused an increase in the binding affinity for GA34, a 2β-hydroxylated GA4. These findings indicate that GID1 originated from HSL and was tinkered to have the specificity for bioactive GAs in the course of plant evolution.

  9. Assessing Gibberellins Oxidase Activity by Anion Exchange/Hydrophobic Polymer Monolithic Capillary Liquid Chromatography-Mass Spectrometry

    PubMed Central

    Liu, Jiu-Feng; Wu, Yan; Feng, Yu-Qi; Yuan, Bi-Feng

    2013-01-01

    Bioactive gibberellins (GAs) play a key regulatory role in plant growth and development. In the biosynthesis of GAs, GA3-oxidase catalyzes the final step to produce bioactive GAs. Thus, the evaluation of GA3-oxidase activity is critical for elucidating the regulation mechanism of plant growth controlled by GAs. However, assessing catalytic activity of endogenous GA3-oxidase remains challenging. In the current study, we developed a capillary liquid chromatography – mass spectrometry (cLC-MS) method for the sensitive assay of in-vitro recombinant or endogenous GA3-oxidase by analyzing the catalytic substrates and products of GA3-oxidase (GA1, GA4, GA9, GA20). An anion exchange/hydrophobic poly([2-(methacryloyloxy)ethyl]trimethylammonium-co-divinylbenzene-co-ethylene glycol dimethacrylate)(META-co-DVB-co-EDMA) monolithic column was successfully prepared for the separation of all target GAs. The limits of detection (LODs, Signal/Noise = 3) of GAs were in the range of 0.62–0.90 fmol. We determined the kinetic parameters (Km) of recombinant GA3-oxidase in Escherichia coli (E. coli) cell lysates, which is consistent with previous reports. Furthermore, by using isotope labeled substrates, we successfully evaluated the activity of endogenous GA3-oxidase that converts GA9 to GA4 in four types of plant samples, which is, to the best of our knowledge, the first report for the quantification of the activity of endogenous GA3-oxidase in plant. Taken together, the method developed here provides a good solution for the evaluation of endogenous GA3-oxidase activity in plant, which may promote the in-depth study of the growth regulation mechanism governed by GAs in plant physiology. PMID:23922762

  10. Assessing gibberellins oxidase activity by anion exchange/hydrophobic polymer monolithic capillary liquid chromatography-mass spectrometry.

    PubMed

    Chen, Ming-Luan; Su, Xin; Xiong, Wei; Liu, Jiu-Feng; Wu, Yan; Feng, Yu-Qi; Yuan, Bi-Feng

    2013-01-01

    Bioactive gibberellins (GAs) play a key regulatory role in plant growth and development. In the biosynthesis of GAs, GA3-oxidase catalyzes the final step to produce bioactive GAs. Thus, the evaluation of GA3-oxidase activity is critical for elucidating the regulation mechanism of plant growth controlled by GAs. However, assessing catalytic activity of endogenous GA3-oxidase remains challenging. In the current study, we developed a capillary liquid chromatography--mass spectrometry (cLC-MS) method for the sensitive assay of in-vitro recombinant or endogenous GA3-oxidase by analyzing the catalytic substrates and products of GA3-oxidase (GA1, GA4, GA9, GA20). An anion exchange/hydrophobic poly([2-(methacryloyloxy)ethyl]trimethylammonium-co-divinylbenzene-co-ethylene glycol dimethacrylate)(META-co-DVB-co-EDMA) monolithic column was successfully prepared for the separation of all target GAs. The limits of detection (LODs, Signal/Noise = 3) of GAs were in the range of 0.62-0.90 fmol. We determined the kinetic parameters (K m) of recombinant GA3-oxidase in Escherichia coli (E. coli) cell lysates, which is consistent with previous reports. Furthermore, by using isotope labeled substrates, we successfully evaluated the activity of endogenous GA3-oxidase that converts GA9 to GA4 in four types of plant samples, which is, to the best of our knowledge, the first report for the quantification of the activity of endogenous GA3-oxidase in plant. Taken together, the method developed here provides a good solution for the evaluation of endogenous GA3-oxidase activity in plant, which may promote the in-depth study of the growth regulation mechanism governed by GAs in plant physiology.

  11. Expression of seed dormancy in grain sorghum lines with contrasting pre-harvest sprouting behavior involves differential regulation of gibberellin metabolism genes.

    PubMed

    Rodríguez, María Verónica; Mendiondo, Guillermina Mónica; Cantoro, Renata; Auge, Gabriela Alejandra; Luna, Virginia; Masciarelli, Oscar; Benech-Arnold, Roberto Luis

    2012-01-01

    Grain sorghum [Sorghum bicolor (L) moench] exhibits intraspecific variability for the rate of dormancy release and pre-harvest sprouting behavior. Two inbred lines with contrasting sprouting response were compared: IS9530 (resistant) and RedlandB2 (susceptible). Precocious dormancy release in RedlandB2 is related to an early loss of embryo sensitivity to ABA and higher levels of gibberellins in imbibed grains as compared with IS9530. With the aim of identifying potential regulatory sites for gibberellin metabolism involved in the expression of dormancy in immature grains of both lines, we carried out a time course analysis of transcript levels of putative gibberellin metabolism genes and hormone content (GA(1), GA(4), GA(8) and GA(34)). A lower embryonic GA(4) level in dormant IS9530 was related to a sharp and transient induction of two SbGA2-oxidase (inactivation) genes. In contrast, these genes were not induced in less dormant RedlandB2, while expression of two SbGA20-oxidase (synthesis) genes increased together with active GA(4) levels before radicle protrusion. Embryonic levels of GA(4) and its catabolite GA(34) correlated negatively. Thus, in addition to the process of gibberellin synthesis, inactivation is also important in regulating GA(4) levels in immature grains. A negative regulation by gibberellins was observed for SbGA20ox2, SbGA2ox1 and SbGA2ox3 and also for SbGID1 encoding a gibberellin receptor. We propose that the coordinated regulation at the transcriptional level of several gibberellin metabolism genes identified in this work affects the balance between gibberellin synthesis and inactivation processes, controlling active GA(4) levels during the expression of dormancy in maturing sorghum grains.

  12. Dark-mediated dormancy release in stratified Lolium rigidum seeds is associated with higher activities of cell wall-modifying enzymes and an apparent increase in gibberellin sensitivity.

    PubMed

    Goggin, Danica E; Powles, Stephen B; Toorop, Peter E; Steadman, Kathryn J

    2011-04-15

    Dormancy release in freshly matured, imbibed annual ryegrass (Lolium rigidum) seeds is inhibited by light and involves a decrease in seed sensitivity to abscisic acid. Other processes involved in dormancy release in the dark were investigated by measuring seed storage compound mobilisation and the activity of cell wall-degrading enzymes. Activities of endo-β-mannanase and total peroxidase were higher in dark-stratified compared to light-stratified seeds, indicating that weakening of the structures constraining the embryo was accelerated in the dark. A dramatic degradation of storage proteins in light-stratified seeds, accompanied by induction of a high molecular mass protease, suggests that maintenance of storage(-like) proteins is also important in dark-mediated dormancy release. α-Amylase activity was induced in dark-stratified seeds at least 48 h prior to radicle emergence upon transfer to conditions permitting germination, or in light-stratified seeds supplied with exogenous gibberellin A(4). This suggests that (a) α-amylase is involved in stimulation of germination of non-dormant L. rigidum seeds, and (b) dark-stratified seeds have an increased sensitivity to gibberellins which permits the rapid induction of α-amylase activity upon exposure to germination conditions. Overall, it appears that a number of processes, although possibly minor in themselves, occur in concert during dark-stratification to contribute to dormancy release. Copyright © 2010 Elsevier GmbH. All rights reserved.

  13. Opposing effects of external gibberellin and Daminozide on Stevia growth and metabolites.

    PubMed

    Karimi, Mojtaba; Hashemi, Javad; Ahmadi, Ali; Abbasi, Alireza; Pompeiano, Antonio; Tavarini, Silvia; Guglielminetti, Lorenzo; Angelini, Luciana G

    2015-01-01

    Steviol glycosides (SVglys) and gibberellins are originated from the shared biosynthesis pathway in Stevia (Stevia rebaudiana Bertoni). In this research, two experiments were conducted to study the opposing effects of external gibberellin (GA3) and Daminozide (a gibberellin inhibitor) on Stevia growth and metabolites. Results showed that GA3 significantly increased the stem length and stem dry weight in Stevia. Total soluble sugar content increased while the SVglys biosynthesis was decreased by external GA3 applying in Stevia leaves. In another experiment, the stem length was reduced by Daminozide spraying on Stevia shoots. The Daminozide did not affect the total SVglys content, while in 30 ppm concentration, significantly increased the soluble sugar production in Stevia leaves. Although the gibberellins biosynthesis pathway has previously invigorated in Stevia leaf, the Stevia response to external gibberellins implying on high precision regulation of gibberellins biosynthesis in Stevia and announces that Stevia is able to kept endogenous gibberellins in a low quantity away from SVglys production. Moreover, the assumption that the internal gibberellins were destroyed by Daminozide, lack of Daminozide effects on SVglys production suggests that gibberellins biosynthesis could not act as a competitive factor for SVglys production in Stevia leaves.

  14. Leaf-Induced Gibberellin Signaling Is Essential for Internode Elongation, Cambial Activity, and Fiber Differentiation in Tobacco Stems[C][W

    PubMed Central

    Dayan, Jonathan; Voronin, Nickolay; Gong, Fan; Sun, Tai-ping; Hedden, Peter; Fromm, Hillel; Aloni, Roni

    2012-01-01

    The gibberellins (GAs) are a group of endogenous compounds that promote the growth of most plant organs, including stem internodes. We show that in tobacco (Nicotiana tabacum) the presence of leaves is essential for the accumulation of bioactive GAs and their immediate precursors in the stem and consequently for normal stem elongation, cambial proliferation, and xylem fiber differentiation. These processes do not occur in the absence of maturing leaves but can be restored by application of C19-GAs, identifying the presence of leaves as a requirement for GA signaling in stems and revealing the fundamental role of GAs in secondary growth regulation. The use of reporter genes for GA activity and GA-directed DELLA protein degradation in Arabidopsis thaliana confirms the presence of a mobile signal from leaves to the stem that induces GA signaling. PMID:22253226

  15. Reactivation of Meristem Activity and Sprout Growth in Potato Tubers Require Both Cytokinin and Gibberellin1[C][W][OA

    PubMed Central

    Hartmann, Anja; Senning, Melanie; Hedden, Peter; Sonnewald, Uwe; Sonnewald, Sophia

    2011-01-01

    Reactivation of dormant meristems is of central importance for plant fitness and survival. Due to their large meristem size, potato (Solanum tuberosum) tubers serve as a model system to study the underlying molecular processes. The phytohormones cytokinins (CK) and gibberellins (GA) play important roles in releasing potato tuber dormancy and promoting sprouting, but their mode of action in these processes is still obscure. Here, we established an in vitro assay using excised tuber buds to study the dormancy-releasing capacity of GA and CK and show that application of gibberellic acid (GA3) is sufficient to induce sprouting. In contrast, treatment with 6-benzylaminopurine induced bud break but did not support further sprout growth unless GA3 was administered additionally. Transgenic potato plants expressing Arabidopsis (Arabidopsis thaliana) GA 20-oxidase or GA 2-oxidase to modify endogenous GA levels showed the expected phenotypical changes as well as slight effects on tuber sprouting. The isopentenyltransferase (IPT) from Agrobacterium tumefaciens and the Arabidopsis cytokinin oxidase/dehydrogenase1 (CKX) were exploited to modify the amounts of CK in transgenic potato plants. IPT expression promoted earlier sprouting in vitro. Strikingly, CKX-expressing tubers exhibited a prolonged dormancy period and did not respond to GA3. This supports an essential role of CK in terminating tuber dormancy and indicates that GA is not sufficient to break dormancy in the absence of CK. GA3-treated wild-type and CKX-expressing tuber buds were subjected to a transcriptome analysis that revealed transcriptional changes in several functional groups, including cell wall metabolism, cell cycle, and auxin and ethylene signaling, denoting events associated with the reactivation of dormant meristems. PMID:21163959

  16. The Reductase Activity of the Arabidopsis Caleosin RESPONSIVE TO DESSICATION20 Mediates Gibberellin-Dependent Flowering Time, Abscisic Acid Sensitivity, and Tolerance to Oxidative Stress1[W

    PubMed Central

    Blée, Elizabeth; Boachon, Benoît; Burcklen, Michel; Le Guédard, Marina; Hanano, Abdulsamie; Heintz, Dimitri; Ehlting, Jürgen; Herrfurth, Cornelia; Feussner, Ivo; Bessoule, Jean-Jacques

    2014-01-01

    Contrasting with the wealth of information available on the multiple roles of jasmonates in plant development and defense, knowledge about the functions and the biosynthesis of hydroxylated oxylipins remains scarce. By expressing the caleosin RESPONSIVE TO DESSICATION20 (RD20) in Saccharomyces cerevisiae, we show that the recombinant protein possesses an unusual peroxygenase activity with restricted specificity toward hydroperoxides of unsaturated fatty acid. Accordingly, Arabidopsis (Arabidopsis thaliana) plants overexpressing RD20 accumulate the product 13-hydroxy-9,11,15-octadecatrienoic acid, a linolenate-derived hydroxide. These plants exhibit elevated levels of reactive oxygen species (ROS) associated with early gibberellin-dependent flowering and abscisic acid hypersensitivity at seed germination. These phenotypes are dependent on the presence of active RD20, since they are abolished in the rd20 null mutant and in lines overexpressing RD20, in which peroxygenase was inactivated by a point mutation of a catalytic histidine residue. RD20 also confers tolerance against stress induced by Paraquat, Rose Bengal, heavy metal, and the synthetic auxins 1-naphthaleneacetic acid and 2,4-dichlorophenoxyacetic acid. Under oxidative stress, 13-hydroxy-9,11,15-octadecatrienoic acid still accumulates in RD20-overexpressing lines, but this lipid oxidation is associated with reduced ROS levels, minor cell death, and delayed floral transition. A model is discussed where the interplay between fatty acid hydroxides generated by RD20 and ROS is counteracted by ethylene during development in unstressed environments. PMID:25056921

  17. A GRAS-like gene of sunflower (Helianthus annuus L.) alters the gibberellin content and axillary meristem outgrowth in transgenic Arabidopsis plants.

    PubMed

    Fambrini, M; Mariotti, L; Parlanti, S; Salvini, M; Pugliesi, C

    2015-11-01

    The GRAS proteins belong to a plant transcriptional regulator family that function in the regulation of plant growth and development. Despite their important roles, in sunflower only one GRAS gene (HaDella1) with the DELLA domain has been reported. Here, we provide a functional characterisation of a GRAS-like gene from Helianthus annuus (Ha-GRASL) lacking the DELLA motif. The Ha-GRASL gene contains an intronless open reading frame of 1,743 bp encoding 580 amino acids. Conserved motifs in the GRAS domain are detected, including VHIID, PFYRE, SAW and two LHR motifs. Within the VHII motif, the P-H-N-D-Q-L residues are entirely maintained. Phylogenetic analysis reveals that Ha-GRASL belongs to the SCARECROW LIKE4/7 (SCL4/7) subfamily of the GRAS consensus tree. Accumulation of Ha-GRASL mRNA at the adaxial boundaries from P6/P7 leaf primordia suggests a role of Ha-GRASL in the initiation of median and basal axillary meristems (AMs) of sunflower. When Ha-GRASL is over-expressed in Arabidopsis wild-type plants, the number of lateral bolts increases differently from untransformed plants. However, Ha-GRASL slightly affects the lateral suppressor (las-4-) mutation. Therefore, we hypothesise that Ha-GRASL and LAS are not functionally equivalent. The over-expression of Ha-GRASL reduces metabolic flow of gibberellins (GAs) in Arabidopsis and this modification could be relevant in AM development. Phylogenetic analysis includes LAS and SCL4/7 in the same major clade, suggesting a more recent separation of these genes with respect to other GRAS members. We propose that some features of their ancestor, as well as AM initiation and outgrowth, are partially retained in both LAS and SCL4/7.

  18. Release of the repressive activity of rice DELLA protein SLR1 by gibberellin does not require SLR1 degradation in the gid2 mutant.

    PubMed

    Ueguchi-Tanaka, Miyako; Hirano, Ko; Hasegawa, Yasuko; Kitano, Hidemi; Matsuoka, Makoto

    2008-09-01

    The rice (Oryza sativa) DELLA protein SLR1 acts as a repressor of gibberellin (GA) signaling. GA perception by GID1 causes SLR1 protein degradation involving the F-box protein GID2; this triggers GA-associated responses such as shoot elongation and seed germination. In GA-insensitive and GA biosynthesis mutants, SLENDER RICE1 (SLR1) accumulates to high levels, and the severity of dwarfism is usually correlated with the level of SLR1 accumulation. An exception is the GA-insensitive F-box mutant gid2, which shows milder dwarfism than mutants such as gid1 and cps even though it accumulates higher levels of SLR1. The level of SLR1 protein in gid2 was decreased by loss of GID1 function or treatment with a GA biosynthesis inhibitor, and dwarfism was enhanced. Conversely, overproduction of GID1 or treatment with GA(3) increased the SLR1 level in gid2 and reduced dwarfism. These results indicate that derepression of SLR1 repressive activity can be accomplished by GA and GID1 alone and does not require F-box (GID2) function. Evidence for GA signaling without GID2 was also provided by the expression behavior of GA-regulated genes such as GA-20oxidase1, GID1, and SLR1 in the gid2 mutant. Based on these observations, we propose a model for the release of GA suppression that does not require DELLA protein degradation.

  19. Gibberellin Structure-Dependent Interaction between Gibberellins and Deoxygibberellin C in the Growth of Dwarf Maize Seedlings.

    PubMed

    Hashimoto, T

    1987-04-01

    The effects of 3-deoxygibberellin C (DGC) on the growth-promoting actions of gibberellins A(1), A(2), A(3), A(4), A(5), A(7), A(8), A(9), A(13), A(18), A(19), A(20), and A(23) (GAn) as well as 13-deoxygibberellin A(5) (deoxy-GA(5)) were tested with seedlings of gibberellin-deficient dwarf mutants (d(2) and d(5)) of maize (Zea mays L.). It was found that DGC promoted the actions of gibberellins having both C-1 double bond and C-3 axial hydroxyl group, and it inhibited the action of gibberellins having the saturated ring A and lacking the C-3 axial hydroxyl group, whereas it did not affect that of the ones having the hydroxyl group. The presence of C-2 double bond, as in GA(5) and deoxy-GA(5), diminished the inhibitory action of DGC. The DGC inhibition was alleviated by raising the doses of the relevant GAs, suggesting that it is a competitive inhibition. These results and the finding that the growth of normal maize and rice seedlings are inhibited by DGC indicate that GA(9), GA(19), GA(20) or other gibberellins having ring A of the same structure are involved in the growth of these plants as active form(s) or as intermediate(s) leading to the active form(s).

  20. Endophytic fungi: resource for gibberellins and crop abiotic stress resistance.

    PubMed

    Khan, Abdul Latif; Hussain, Javid; Al-Harrasi, Ahmed; Al-Rawahi, Ahmed; Lee, In-Jung

    2015-03-01

    The beneficial effects of endophytes on plant growth are important for agricultural ecosystems because they reduce the need for fertilizers and decrease soil and water pollution while compensating for environmental perturbations. Endophytic fungi are a novel source of bioactive secondary metabolites; moreover, recently they have been found to produce physiologically active gibberellins as well. The symbiosis of gibberellins producing endophytic fungi with crops can be a promising strategy to overcome the adverse effects of abiotic stresses. The association of such endophytes has not only increased plant biomass but also ameliorated plant-growth during extreme environmental conditions. Endophytic fungi represent a trove of unexplored biodiversity and a frequently overlooked component of crop ecology. The present review describes the role of gibberellins producing endophytic fungi, suggests putative mechanisms involved in plant endophyte stress interactions and discusses future prospects in this field.

  1. Preparation of Radioactive Gibberellin A1 and its Metabolism in Dwarf Peas

    PubMed Central

    Kende, H.

    1967-01-01

    Gibberellin A1-3,4-3H was prepared by selective catalytic reduction of gibberellic acid with a mixture of tritium and hydrogen. 3H-GA1 was applied at physiological concentrations to dwarf peas and the metabolism of the hormone was investigated. 3H-GA1 was converted to an acidic, biologically active compound. Radioactive but biologically inactive compounds were also found in the neutral fraction and could not be converted to acidic gibberellins by hydrolysis. No attachment of gibberellin to any macromolecular fraction was evident. PMID:16656696

  2. Colonization by the endophyte Piriformospora indica leads to early flowering in Arabidopsis thaliana likely by triggering gibberellin biosynthesis.

    PubMed

    Kim, Dongjin; Abdelaziz, Mohamad E; Ntui, Valentine Otang; Guo, Xiujie; Al-Babili, Salim

    2017-09-02

    Piriformospora indica is an endophytic fungus colonizing roots of a wide variety of plants. Previous studies showed that P. indica promotes early flowering and plant growth in the medicinal plant Coleus forskohlii. To determine the impact of P. indica on flowering time in Arabidopsis, we co-cultivated the plants with P. indica under long day condition. P. indica inoculated Arabidopsis plants displayed significant early flowering phenotype. qRT-PCR analysis of colonized plants revealed an up-regulation of flowering regulatory (FLOWERING LOCUS T, LEAFY, and APETALA1) and gibberellin biosynthetic (Gibberellin 20-Oxidase2, Gibberellin 3-Oxidase1 and Gibberellin requiring1) genes, while the flowering-repressing gene FLOWERING LOCUS C was down regulated. Quantification of gibberellins content showed that the colonization with P. indica caused an increase in GA4 content. Compared to wild-type plants, inoculation of the Arabidopsis ga5 mutant affected in gibberellin biosynthetic gene led to less pronounced changes in the expression of genes regulating flowering and to a lower increase in GA4 content. Taken together, our data indicate that P. indica promotes early flowering in Arabidopsis likely by increasing gibberellin content. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Gibberellin (GA3) enhances cell wall invertase activity and mRNA levels in elongating dwarf pea (Pisum sativum) shoots

    NASA Technical Reports Server (NTRS)

    Wu, L. L.; Mitchell, J. P.; Cohn, N. S.; Kaufman, P. B.

    1993-01-01

    The invertase (EC 3.2.1.26) purified from cell walls of dwarf pea stems to homogeneity has a molecular mass of 64 kilodaltons (kD). Poly(A)+RNA was isolated from shoots of dwarf pea plants, and a cDNA library was constructed using lambda gt11 as an expression vector. The expression cDNA library was screened with polyclonal antibodies against pea cell wall invertase. One invertase cDNA clone was characterized as a full-length cDNA with 1,863 base pairs. Compared with other known invertases, one homologous region in the amino acid sequence was found. The conserved motif, Asn-Asp-Pro-Asn-Gly, is located near the N-terminal end of invertase. Northern blot analysis showed that the amount of invertase mRNA (1.86 kb) was rapidly induced to a maximal level 4 h after GA3 treatment, then gradually decreased to the control level. The mRNA level at 4 h in GA3-treated peas was fivefold higher than that of the control group. The maximal increase in activity of pea cell wall invertase elicited by GA3 occcured at 8 h after GA3 treatment. This invertase isoform was shown immunocytochemically to be localized in the cell walls, where a 10-fold higher accumulation occurred in GA3-treated tissue compared with control tissue. This study indicates that the expression of the pea shoot cell-wall invertase gene could be regulated by GA3 at transcriptional and/or translational levels.

  4. Gibberellin (GA3) enhances cell wall invertase activity and mRNA levels in elongating dwarf pea (Pisum sativum) shoots

    NASA Technical Reports Server (NTRS)

    Wu, L. L.; Mitchell, J. P.; Cohn, N. S.; Kaufman, P. B.

    1993-01-01

    The invertase (EC 3.2.1.26) purified from cell walls of dwarf pea stems to homogeneity has a molecular mass of 64 kilodaltons (kD). Poly(A)+RNA was isolated from shoots of dwarf pea plants, and a cDNA library was constructed using lambda gt11 as an expression vector. The expression cDNA library was screened with polyclonal antibodies against pea cell wall invertase. One invertase cDNA clone was characterized as a full-length cDNA with 1,863 base pairs. Compared with other known invertases, one homologous region in the amino acid sequence was found. The conserved motif, Asn-Asp-Pro-Asn-Gly, is located near the N-terminal end of invertase. Northern blot analysis showed that the amount of invertase mRNA (1.86 kb) was rapidly induced to a maximal level 4 h after GA3 treatment, then gradually decreased to the control level. The mRNA level at 4 h in GA3-treated peas was fivefold higher than that of the control group. The maximal increase in activity of pea cell wall invertase elicited by GA3 occcured at 8 h after GA3 treatment. This invertase isoform was shown immunocytochemically to be localized in the cell walls, where a 10-fold higher accumulation occurred in GA3-treated tissue compared with control tissue. This study indicates that the expression of the pea shoot cell-wall invertase gene could be regulated by GA3 at transcriptional and/or translational levels.

  5. [Effect of triterpenoid glycosides on alpha- and beta-amylase activity and total protein content in wheat seedlings].

    PubMed

    Davidiants, E S

    2011-01-01

    Influence of the aleanolic acid glycosides from Silphium perfoliatum L. (silphioside B, C, E and G) and their progenins on the amylase activity and total protein content in wheat seedlings was studied. Treatment of the Triticum aestivum L. seeds with 1-10 microM water solutions of mono- and diglycosides (mono- and bisdesmosines) elevated the alpha-amylase and total amylase activities in seedlings. Silphioside E containing three glucose moieties in its molecule did not change alpha-amylase activity, but it did if bis-triglycoside acetylated carbohydrate (as in silphioside C). Effects of 5-10 microM solutions of the active glycosides was comparable with that of exogenous gibberellin A3 and 6-benzylaminopurine.

  6. Gibberellins regulate seed germination in tomato by endosperm weakening: a study with gibberellin-deficient mutants.

    PubMed

    Groot, S P; Karssen, C M

    1987-08-01

    The germination of seeds of tomato [Lycopersicon esculentum (L.) Mill.] cv. Moneymaker has been compared with that of seeds of the gibberellin-deficient dwarf-mutant line ga-1, induced in the same genetic background. Germination of tomato seeds was absolutely dependent on the presence of either endogenous or exogenous gibberellins (GAs). Gibberellin A4+7 was 1000-fold more active than commercial gibberellic acid in inducing germination of the ga-1 seeds. Red light, a preincubation at 2°C, and ethylene did not stimulate germination of ga-1 seeds in the absence of GA4+7; however, fusicoccin did stimulate germination independently. Removal of the endosperm and testa layers opposite the radicle tip caused germination of ga-1 seeds in water. The seedlings and plants that develop from the detipped ga-1 seeds exhibited the extreme dwarfy phenotype that is normal to this genotype. Measurements of the mechanical resistance of the surrounding layers showed that the major action of GAs was directed to the weakening of the endosperm cells around the radicle tip. In wild-type seeds this weakening occurred in water before radicle protrusion. In ga-1 seeds a similar event was dependent on GA4+7, while fusicoccin also had some activity. Simultaneous incubation of de-embryonated endosperms and isolated axes showed that wild-type embryos contain and endosperm-weakening factor that is absent in ga-1 axes and is probably a GA. Thus, an endogenous GA facilitates germination in tomato seeds by weakening the mechanical restraint of the endosperm cells to permit radicle protrusion.

  7. [Recent advances in the analysis of gibberellins plant hormones].

    PubMed

    Zhang, Xiaona; Lu, Minghua; Xu, Linfang; Xiao, Rui; Cai, Zongwei

    2015-08-01

    Gibberellins (GAs) are a class of phytohormones that exert profound and diverse effects on plant growth and development, such as seed germination and leaf expansion. Up to now, 136 members of GAs have been identified and recognized. All known GAs are diterpenoid acids with similar chemical structures, only double bonds, hydroxyl numbers and locations on gibberellin alkane skeleton are different. However, the content of GAs in plants is of ultra trace levels (usually at ng/g and even pg/g levels) with little ultraviolet (UV) absorption, no fluorescence and no distinguishing chemical characteristics. Moreover, the matrix of plant samples is complicated. Thus, quantification of GAs is always extremely difficult. Nowadays, the bottle necks for the study of GAs in plants are due to the lack of efficient sample preparation and sensitive detection techniques. This article reviews the analytical methods for determination of GAs in recent years, hoping to provide some references to develop new methods and techniques.

  8. Identification of Endogenous Gibberellins from Sorghum1

    PubMed Central

    Rood, Stewart B.; Larsen, Karen M.; Mander, Lewis N.; Abe, Hiroshi; Pharis, Richard P.

    1986-01-01

    Gibberellins (GA) A1, A19, and A20 were identified in shoot cylinders containing the apical meristems from sorghum (Sorghum bicolor L.). Extracts were purified by sequential SiO2 partition chromatography and reversed-phase C18 high performance liquid chromatography and biologically active (dwarf rice cv Tan-ginbozu microdrop assay) fractions were subjected to gas chromatography-selected ion monitoring. Based on the use of [3H]GA and [2H](d2)GA internal standards, amounts of GA1, GA19, and GA20 were estimated to be 0.7, 8.8, and 1.5 namograms per gram dry weight of tissue, respectively. PMID:16665017

  9. Bacterial endophyte Sphingomonas sp. LK11 produces gibberellins and IAA and promotes tomato plant growth.

    PubMed

    Khan, Abdul Latif; Waqas, Muhammad; Kang, Sang-Mo; Al-Harrasi, Ahmed; Hussain, Javid; Al-Rawahi, Ahmed; Al-Khiziri, Salima; Ullah, Ihsan; Ali, Liaqat; Jung, Hee-Young; Lee, In-Jung

    2014-08-01

    Plant growth promoting endophytic bacteria have been identified as potential growth regulators of crops. Endophytic bacterium, Sphingomonas sp. LK11, was isolated from the leaves of Tephrosia apollinea. The pure culture of Sphingomonas sp. LK11 was subjected to advance chromatographic and spectroscopic techniques to extract and isolate gibberellins (GAs). Deuterated standards of [17, 17-(2)H2]-GA4, [17, 17-(2)H2]-GA9 and [17, 17-(2)H2]-GA20 were used to quantify the bacterial GAs. The analysis of the culture broth of Sphingomonas sp. LK11 revealed the existence of physiologically active gibberellins (GA4: 2.97 ± 0.11 ng/ml) and inactive GA9 (0.98 ± 0.15 ng/ml) and GA20 (2.41 ± 0.23). The endophyte also produced indole acetic acid (11.23 ± 0.93 μM/ml). Tomato plants inoculated with endophytic Sphingomonas sp. LK11 showed significantly increased growth attributes (shoot length, chlorophyll contents, shoot, and root dry weights) compared to the control. This indicated that such phyto-hormones-producing strains could help in increasing crop growth.

  10. Endogenous Gibberellins of Pine Pollen

    PubMed Central

    Kamienska, Aniela; Durley, Richard C.; Pharis, Richard P.

    1976-01-01

    Gibberellins A1 and A34 (possibly A2) were found as products of metabolism of 1,2-[3H]GA4 during germination of Pinus attenuata pollen. The conversion from GA4 to GA1 and GA34 occurred as hydroxylations at atoms C-13 and C-2 of the ent-gibberellane skeleton, respectively. Percentage interconversion of the GA4 absorbed was in the range of 0.15 to 0.43% for GA1 and 1.54 to 3.22% for GA34. Identifications were made on a gas-liquid chromatograph with radioactive monitoring by comparison with standards. PMID:16659622

  11. Endogenous Gibberellins and Inhibitors in Relation to Flower Induction and Inflorescence Development in the Olive

    PubMed Central

    Badr, Sayed A.; Hartmann, Hudson T.; Martin, George C.

    1970-01-01

    Comparative analyses of reproductive and vegetative tissues of the olive (Olea europaea L. cv. Manzanillo) for endogenous hormones, particularly inhibitors and gibberellin like substances, were made to study the relation between such hormones and thermoinduction of flowering. Qualitative and quantitative changes in gibberellin-like subtance(s) were observed in lateral buds (potential flower buds) but not in leaves or terminal buds (potential vegetative buds) sampled from orchard trees at intervals during the winter and spring. At least two types of gibberellin-like substances were found in extracts of lateral buds; their levels increased progressively during the low temperature induction period, reaching a maximum shortly before floral initiation. Two types of inhibitors were extracted from buds and leaves. A nonacidic type did not change during the induction stage but decreased considerably during the initiation period. An acidic inhibitor, which was identified as an abscisic acid-like substance, was present at a relatively lower level in lateral (flower) buds than in terminal (vegetative) buds during the induction period. It was concluded that winter chilling induces flowering in the olive possibly by altering a balance between endogenous gibberellins and inhibitors, including abscisic acid. Inflorescence development following the winter chilling period was associated with an increase in the level of endogenous inhibitors and gibberellins. Shoot growth, however, was correlated with a decrease in the inhibitor(s) level. A rise in gibberellin-like activity is believed to be a result, not a cause, of shoot growth. Images PMID:16657528

  12. Characterization of gibberellin-signalling elements during plum fruit ontogeny defines the essentiality of gibberellin in fruit development.

    PubMed

    El-Sharkawy, Islam; Sherif, Sherif; El Kayal, Walid; Mahboob, Abdullah; Abubaker, Kamal; Ravindran, Pratibha; Jyothi-Prakash, Pavithra A; Kumar, Prakash P; Jayasankar, Subramanian

    2014-03-01

    Fruit growth is a coordinated, complex interaction of cell division, differentiation and expansion. Gibberellin (GA) involvement in the reproductive events is an important aspect of GA effects. Perennial fruit-trees such as plum (Prunus salicina L.) have distinct features that are economically important and provide opportunities to dissect specific GA mechanisms. Currently, very little is known on the molecular mechanism(s) mediating GA effects on fruit development. Determination of bioactive GA content during plum fruit ontogeny revealed that GA1 and GA4 are critical for fruit growth and development. Further, characterization of several genes involved in GA-signalling showed that their transcriptional regulation are generally GA-dependent, confirming their involvement in GA-signalling. Based on these results, a model is presented elucidating how the potential association between GA and other hormones may contribute to fruit development. PslGID1 proteins structure, Y2H and BiFC assays indicated that plum GA-receptors can form a complex with AtDELLA-repressors in a GA-dependent manner. Moreover, phenotypical-, molecular- and GA-analyses of various Arabidopsis backgrounds ectopically expressing PslGID1 sequences provide evidence on their role as active GA-signalling components that mediate GA-responsiveness. Our findings support the critical contribution of GA alone or in association with other hormones in mediating plum fruit growth and development.

  13. Gibberellin Metabolism in Maize (The Stepwise Conversion of Gibberellin A12-Aldehyde to Gibberellin A20.

    PubMed

    Kobayashi, M.; Spray, C. R.; Phinney, B. O.; Gaskin, P.; MacMillan, J.

    1996-02-01

    The stepwise metabolism of gibberellin A12-aldehyde (GA12-aldehyde) to GA20 is demonstrated from seedling shoots of maize (Zea mays L.). The labeled substrates [13C,3H]GA12-aldehyde, [13C,3H]GA12, [14C4]GA53, [14C4/2H2]GA44, and [14C4/2H2]GA19 were fed individually to dwarf-5 vegetative shoots. Both [13C,3H]GA12-aldehyde and [13C,3H]GA12 were also added individually to normal shoots. The labeled metabolites were identified by full-scan gas chromatography-mass spectrometry and Kovats retention indices. GA12-aldehyde was metabolized to GA53-aldehyde, GA12, GA53, GA44, and GA19; GA12 was metabolized to 2[beta]-hydroxy-GA12, GA53, 2[beta]-hydroxyGA53, GA44, 2[beta]-hydroxyGA44, and GA19; GA53 was metabolized to GA44, GA19, GA20, and GA1; GA44 was metabolized to GA19; and GA19 was metabolized to GA20. These results, together with previously published data from this laboratory, document the most completely defined gibberellin pathway for the vegetative tissues of higher plants.

  14. Evidence for Phytochrome Regulation of Gibberellin A20 3β-Hydroxylation in Shoots of Dwarf (lele) Pisum sativum L. 1

    PubMed Central

    Campell, Bruce R.; Bonner, Bruce A.

    1986-01-01

    The effect of light on the dwarfing allele, le, in Pisum sativum L. was tested as the growth response to gibberellins prior to or beyond the presumed block in the gibberellin biosynthetic pathway. The response to the substrate (GA20), the product (GA1), and a nonendogenous early precursor (steviol) was compared in plants bearing the normal Le and the deficient lele genotypes in plants made low in gibberellin content genetically (nana lines) or by paclobutrazol treatment to tall (cv Alaska) and dwarf (cv Progress) peas. Both genotypes responded to GA1 under red irradiation and in darkness. The lele plants grew in response to GA20 and steviol in darkness but showed a much smaller response when red irradiated. The Le plants responded to GA20 and steviol in both light and darkness. The red effects on lele plants were largely reversible by far-red irradiation. It is concluded that the deficiency in 3β-hydroxylation of GA20 to GA1 in genotype lele is due to a Pfr-induced blockage in the expression of that activity. PMID:16665165

  15. CbCBF from Capsella bursa-pastoris enhances cold tolerance and restrains growth in Nicotiana tabacum by antagonizing with gibberellin and affecting cell cycle signaling.

    PubMed

    Zhou, Mingqi; Xu, Ming; Wu, Lihua; Shen, Chen; Ma, Hong; Lin, Juan

    2014-06-01

    Plant cells respond to cold stress via a regulatory mechanism leading to enhanced cold acclimation accompanied by growth retardation. The C-repeat binding factor (CBF) signaling pathway is essential for cold response of flowering plants. Our previously study documented a novel CBF-like gene from the cold-tolerant Capsella bursa-pastoris named CbCBF, which was responsive to chilling temperatures. Here, we show that CbCBF expression is obviously responsive to chilling, freezing, abscisic acid, gibberellic acid (GA), indoleacetic acid or methyl jasmonate treatments and that the CbCBF:GFP fusion protein was localized to the nucleus. In addition, CbCBF overexpression conferred to the cold-sensitive tobacco plants enhanced tolerance to chilling and freezing, as well as dwarfism and delayed flowering. The leaf cells of CbCBF overexpression tobacco lines attained smaller sizes and underwent delayed cell division with reduced expression of cyclin D genes. The dwarfism of CbCBF transformants can be partially restored by GA application. Consistently, CbCBF overexpression reduced the bioactive gibberellin contents and disturbed the expression of gibberellin metabolic genes in tobacco. Meanwhile, cold induced CbCBF expression and cold tolerance in C. bursa-pastoris are reduced by GA. We conclude that CbCBF confers cold resistance and growth inhibition to tobacco cells by interacting with gibberellin and cell cycle pathways, likely through activation of downstream target genes.

  16. Gibberellin biosynthesis in Gibberlla fujikuroi

    SciTech Connect

    Johnson, S.W.; Coolbaugh, R.C. )

    1989-04-01

    Gibberellins (GAs) are a group of plant growth hormones which were first isolated from the fungus Gibberella fujikuori. We have examined the biosynthesis of GAs in this fungus in liquid cultures using HPLC followed by GC-MS. Furthermore we have used cell-free enzyme extracts with {sup 14}C-labeled intermediates to examine the regulation of specific parts of the biosynthetic pathway. GA{sub 3} is the predominant GA in well aerated cultures. GA{sub 4} and GA{sub 7}, intermediates in GA{sub 3} biosynthesis, accumulate in cultures with low levels of dissolved oxygen, but are not detectable in more aerated cultures. Light stimulates GA production in G. fujikuroi cultures grown from young stock. Cell-free enzyme studies indicate that light has no effect on incorporation of mevalonic acid into kaurene, but does significantly stimulate the oxidation of kaurenoic acid.

  17. Oligo-carrageenan kappa-induced reducing redox status and activation of TRR/TRX system increase the level of indole-3-acetic acid, gibberellin A3 and trans-zeatin in Eucalyptus globulus trees.

    PubMed

    González, Alberto; Contreras, Rodrigo A; Zúiga, Gustavo; Moenne, Alejandra

    2014-08-20

    Eucalyptus globulus trees treated with oligo-carrageenan (OC) kappa showed an increase in NADPH, ascorbate and glutathione levels and activation of the thioredoxin reductase (TRR)/thioredoxin (TRX) system which enhance photosynthesis, basal metabolism and growth. In order to analyze whether the reducing redox status and the activation of thioredoxin reductase (TRR)/thioredoxin (TRX) increased the level of growth-promoting hormones, trees were treated with water (control), with OC kappa, or with inhibitors of ascorbate synthesis, lycorine, glutathione synthesis, buthionine sulfoximine (BSO), NADPH synthesis, CHS-828, and thioredoxin reductase activity, auranofine, and with OC kappa, and cultivated for four additional months. Eucalyptus trees treated with OC kappa showed an increase in the levels of the auxin indole 3-acetic acid (IAA), gibberellin A3 (GA3) and the cytokinin trans-zeatin (t-Z) as well as a decrease in the level of the brassinosteroid epi-brassinolide (EB). In addition, treatment with lycorine, BSO, CHS-828 and auranofine inhibited the increase in IAA, GA3 and t-Z as well as the decrease in EB levels. Thus, the reducing redox status and the activation of TRR/TRX system induced by OC kappa increased the levels of IAA, GA3 and t-Z levels determining, at least in part, the stimulation of growth in Eucalyptus trees.

  18. Plant hormones in arbuscular mycorrhizal symbioses: an emerging role for gibberellins

    PubMed Central

    Foo, Eloise; Ross, John J.; Jones, William T.; Reid, James B.

    2013-01-01

    Background and Aims Arbuscular mycorrhizal symbioses are important for nutrient acquisition in >80 % of terrestrial plants. Recently there have been major breakthroughs in understanding the signals that regulate colonization by the fungus, but the roles of the known plant hormones are still emerging. Here our understanding of the roles of abscisic acid, ethylene, auxin, strigolactones, salicylic acid and jasmonic acid is discussed, and the roles of gibberellins and brassinosteroids examined. Methods Pea mutants deficient in gibberellins, DELLA proteins and brassinosteroids are used to determine whether fungal colonization is altered by the level of these hormones or signalling compounds. Expression of genes activated during mycorrhizal colonization is also monitored. Key Results Arbuscular mycorrhizal colonization of pea roots is substantially increased in gibberellin-deficient na-1 mutants compared with wild-type plants. This is reversed by application of GA3. Mutant la cry-s, which lacks gibberellin signalling DELLA proteins, shows reduced colonization. These changes were parallelled by changes in the expression of genes associated with mycorrhizal colonization. The brassinosteroid-deficient lkb mutant showed no change in colonization. Conclusions Biologically active gibberellins suppress arbuscule formation in pea roots, and DELLA proteins are essential for this response, indicating that this role occurs within the root cells. PMID:23508650

  19. Content Analysis in Systems Engineering Acquisition Activities

    DTIC Science & Technology

    2016-04-30

    qÜáêíÉÉåíÜ=^ååì~ä= ^Åèìáëáíáçå=oÉëÉ~êÅÜ= póãéçëáìã= tÉÇåÉëÇ~ó=pÉëëáçåë= sçäìãÉ=f= = Content Analysis in Systems Engineering Acquisition Activities Karen...of Design Thinking Ronald Giachetti, Chair and Professor, NPS Clifford Whitcomb, Professor, NPS Content Analysis in Systems Engineering...Åèìáëáíáçå=oÉëÉ~êÅÜ=mêçÖê~ãW= `êÉ~íáåÖ=póåÉêÖó=Ñçê=fåÑçêãÉÇ=`Ü~åÖÉ= - 57 - Content Analysis in Systems Engineering Acquisition Activities

  20. [Changes of endogenous hormone contents and antioxidative enzyme activities in wheat leaves under low temperature stress at jointing stage].

    PubMed

    Li, Chun-yan; Xu, Wen; Liu, Li-wei; Yang, Jing; Zhu, Xin-kai; Guo, Wen-shan

    2015-07-01

    Low temperature stresses (-3 and -5 °C) were simulated using artificial temperature-controlled phytotrons to study the freezing rate, the contents of endogenous hormones, and the activities of antioxidative enzymes in the leaves of wheat plants of Yangmai 16 (YM 16) and Xumai 30 (XM 30) at jointing stage. The grade and index of freezing injury increased with lower temperature and longer stress. The freezing rate was at the 5th level and the main stems and tillers of both cultivars were finally dead under -5 °C lasting for 72 h. On the last day of stress initiation, the contents of abscisic acid (ABA) and zeatin riboside (ZR), and the activities of superoxide dismutase (SOD), peroxide dismutase (POD), and catalase (CAT) in leaves increased at the beginning and then declined as low temperature progressed. On the 3rd day after stress, the contents of ABA and ZR and the activities of antioxidative enzymes were higher than those on the last day of cold stress, and then reduced to the level of the control on the 6th day after stress. The content of gibberellins (GA3) was lowered by cold stress. For YM 16, GA3 content increased from the 3rd day to the 6th day after cold stress, whereas, for XM 30, it increased first and then decreased. For the treatment of -5 °C lasting for 72 h, the contents of hormones and the activities of antioxidative enzymes were significantly lower than those of the other treatments. Correlation analyses showed that higher ABA and ZR contents, and higher SOD, POD and CAT activities as well as lower GA3 content could alleviate the low-temperature injury in wheat plants under low temperature stress.

  1. Advertising Content in Physical Activity Print Materials.

    ERIC Educational Resources Information Center

    Cardinal, Bradley J.

    2002-01-01

    Evaluated the advertising content contained in physical activity print materials. Analysis of print materials obtained from 80 sources (e.g., physicians' offices and fitness events) indicated that most materials contained some form of advertising. Materials coming from commercial product vendors generally contained more advertising than materials…

  2. Localization of phytochrome in etioplasts and its regulation in vitro of gibberellin levels

    PubMed Central

    Evans, A.; Smith, H.

    1976-01-01

    Etioplasts isolated from barley leaves and purified on a Sephadex G-50 (coarse) column were characterized by electron microscopy and nucleic acid analysis. The majority of etioplasts retained an intact outer envelope, and contamination by other fragments was extremely low. The level of gibberellin-like substances extractable from intact etioplast suspensions was enhanced within 5 min of the termination of a saturating red irradiation, and the response was far-red reversible. Ultra-sonication caused a 3-fold increase in extractable activity both in dark control suspension and suspensions treated with red light. It is concluded that phytochrome, as a function of its interconversions, probably causes the transport of gibberellin from inside the etioplast into the surrounding medium. This leads to increased production of active gibberellins, possibly by release of feedback control of late steps of the biosynthetic pathway. Dual wavelength difference spectrophotometry has demonstrated the presence of a proportion of total cellular phytochrome within the etioplast. Images PMID:16592300

  3. Plant growth enhancement and associated physiological responses are coregulated by ethylene and gibberellin in response to harpin protein Hpa1.

    PubMed

    Li, Xiaojie; Han, Bing; Xu, Manyu; Han, Liping; Zhao, Yanying; Liu, Zhilan; Dong, Hansong; Zhang, Chunling

    2014-04-01

    The harpin protein Hpa1 produced by the bacterial blight pathogen of rice induces several growth-promoting responses in plants, activating the ethylene signaling pathway, increasing photosynthesis rates and EXPANSIN (EXP) gene expression levels, and thereby enhancing the vegetative growth. This study was attempted to analyze any mechanistic connections among the above and the role of gibberellin in these responses. Hpa1-induced growth enhancement was evaluated in Arabidopsis, tomato, and rice. And growth-promoting responses were determined mainly as an increase of chlorophyll a/b ratio, which indicates a potential elevation of photosynthesis rates, and enhancements of photosynthesis and EXP expression in the three plant species. In Arabidopsis, Hpa1-induced growth-promoting responses were partially compromised by a defect in ethylene perception or gibberellin biosynthesis. In tomato and rice, compromises of Hpa1-induced growth-promoting responses were caused by a pharmacological treatment with an ethylene perception inhibitor or a gibberellin biosynthesis inhibitor. In the three plant species, moreover, Hpa1-induced growth-promoting responses were significantly impaired, but not totally eliminated, by abolishing ethylene perception or gibberellin synthesis. However, simultaneous nullifications in both ethylene perception and gibberellin biosynthesis almost canceled the full effects of Hpa1 on plant growth, photosynthesis, and EXP2 expression. Theses results suggest that ethylene and gibberellin coregulate Hpa1-induced plant growth enhancement and associated physiological and molecular responses.

  4. Gibberellins and gravitropism in maize shoots: endogenous gibberellin-like substances and movement and metabolism of (/sup 3/)gibberellin A

    SciTech Connect

    Rood, S.B.; Kaufman, P.B.; Abe, H.; Pharis, R.P.

    1987-03-01

    (/sup 3/H)Gibberellin A/sub 20/(GA/sub 20/) of high specific radioactivity was applied equilaterally in a ring of microdrops to the internodal pulvinus of shoots of 3-week-old vertical normal maize (Zea mays L.), and to a pleiogravitropic (prostrate) maize mutant, lazy (la). All plants converted the (/sup 3/H)GA/sub 1//sup -/ and (/sup 3/H)GA/sub 29/-like metabolites as well as to several metabolites with the partitioning and chromatographic behavior of glucosyl conjugates of (/sup 3/H)GA/sub 1/(/sup 3/H)GA/sub 29/, and (/sup 3/H)GA/sub 8/. The tentative identification of these putative (/sup 3/H)GA glucosyl conjugates was further supported by the release of the free (/sup 3/H)GA moiety after cleavage with cellulase. Within 12 hours of the (/sup 3/H)GA/sub 20/ feed, there was a significantly higher proportion of total radioactivity in lower than in upper halves of internode and leaf sheaf pulvini in gravistimulated normal maize. Further, there was a significantly higher proportion of putative free GA metabolites of (/sup 3/H)GA/sub 20/, especially (/sup 3/H) GA/sub 1/, in the lower halves of normal maize relative to upper halves. The differential localization of the metabolites between upper and lower halves was not apparent in the pleiogravitropic mutant, la. Endogenous GA-like substances were also examined in gravistimulated maize shoots. Forty-eight hours after gravistimulation of 3-week-old maize seedlings, endogenous free GA-like substances in upper and lower leaf sheath and internode pulvini halves were extracted, chromatographed, and bioassayed using the Tanginbozu dwarf rice microdroassay. Lower halves contained higher total levels of GA-like activity.

  5. Further Experiments on Gibberellin-Stimulated Amylase Production in Cereal Grains

    ERIC Educational Resources Information Center

    Coppage, Jo; Hill, T. A.

    1973-01-01

    Experiments conducted on wheat and barley grains to analyze activities of alpha- and beta-amylase enzymes. Gibberellins were used exogenously. Techniques are described in detail. Results on different cultivars revealed that beta-amylase was not an invariable result of imbibition. Techniques employed can be used by school students. (PS)

  6. Further Experiments on Gibberellin-Stimulated Amylase Production in Cereal Grains

    ERIC Educational Resources Information Center

    Coppage, Jo; Hill, T. A.

    1973-01-01

    Experiments conducted on wheat and barley grains to analyze activities of alpha- and beta-amylase enzymes. Gibberellins were used exogenously. Techniques are described in detail. Results on different cultivars revealed that beta-amylase was not an invariable result of imbibition. Techniques employed can be used by school students. (PS)

  7. Gibberellin-like effects of KAR1 on dormancy release of Avena fatua caryopses include participation of non-enzymatic antioxidants and cell cycle activation in embryos.

    PubMed

    Cembrowska-Lech, Danuta; Kępczyński, Jan

    2016-02-01

    The induction of dormancy release and germination of Avena fatua caryopses by KAR 1 involves ABA degradation to phaseic acid. Both, KAR 1 and GA 3 , control the AsA-GSH cycle, DNA replication and accumulation of β-tubulin in embryos before caryopses germination. Avena fatua caryopses cannot germinate in darkness at 20 °C because of dormancy, but karrikinolide-1 (KAR1), a compound in plant-derived smoke, and gibberellic acid (GA3) induced an almost complete germination. The radicle protrusion through the coleorhiza was preceded by increased water uptake, rupture of coat, increased embryo size and coleorhiza length as well as coleorhiza protrusion through covering structures. The stimulatory effect of KAR1 was correlated with the reduced content of abscisic acid (ABA) and an increase in phaseic acid (PA) in embryos from caryopses before coleorhiza protrusion. Two non-enzymatic antioxidants, ascorbate (AsA) and reduced glutathione (GSH), did not affect the germination of dormant caryopses, but in the presence of KAR1 or GA3 they only slightly delayed the germination. The stimulatory effect of KAR1 or GA3 on the final germination percentage was markedly antagonized by lycorine, an AsA biosynthesis inhibitor. KAR1 and GA3 applied during caryopses imbibition resulted in increases of AsA, dehydroascorbate (DHA) and GSH, but reduced the embryos' oxidized glutathione (GSSG) content. Furthermore, both KAR1 and GA3 induced an additional ascorbate peroxidase (APX) isoenzyme and increased the glutathione reductase (GR) activity. Both compounds stimulated β-tubulin accumulation in radicle+coleorhiza (RC) and plumule+coleoptile (PC), and enhanced the transition from G1 to S and also from S to G2 phases. The comparison of the effects produced by KAR1 and GA3  shows a similar action; thus the KAR1 effect may not be specific. The study provides new data regarding the mechanism with which KAR1, a representative of a novel class of plant growth regulators, regulates dormancy and

  8. The characterization of transgenic tomato overexpressing gibberellin 20-oxidase reveals induction of parthenocarpic fruit growth, higher yield, and alteration of the gibberellin biosynthetic pathway.

    PubMed

    García-Hurtado, Noemí; Carrera, Esther; Ruiz-Rivero, Omar; López-Gresa, Maria Pilar; Hedden, Peter; Gong, Fan; García-Martínez, José Luis

    2012-10-01

    Fruit-set and growth in tomato depend on the action of gibberellins (GAs). To evaluate the role of the GA biosynthetic enzyme GA 20-oxidase (GA20ox) in that process, the citrus gene CcGA20ox1 was overexpressed in tomato (Solanum lycopersicum L.) cv Micro-Tom. The transformed plants were taller, had non-serrated leaves, and some flowers displayed a protruding stigma due to a longer style, thus preventing self-pollination, similar to GA(3)-treated plants. Flowering was delayed compared with wild-type (WT) plants. Both yield and number of fruits per plant, some of them seedless, were higher in the transgenic plants. The Brix index value of fruit juice was also higher due to elevated citric acid content, but not glucose or fructose content. When emasculated, 14-30% of ovaries from transgenic flowers developed parthenocarpically, whereas no parthenocarpy was found in emasculated WT flowers. The presence of early-13-hydroxylation and non-13-hydroxylation GA pathways was demonstrated in the shoot and fruit of Micro-Tom, as well as in two tall tomato cultivars (Ailsa Craig and UC-82). The transgenic plants had altered GA profiles containing higher concentrations of GA(4), from the non-13-hydroxylation pathway, which is generally a minor active GA in tomato. The effect of GA(4) application in enhancing stem growth and parthenocarpic fruit development was proportional to dose, with the same activity as GA(1). The results support the contention that GA20ox overexpression diverts GA metabolism from the early-13-hydroxylation pathway to the non-13-hydroxylation pathway. This led to enhanced GA(4) synthesis and higher yield, although the increase in GA(4) content in the ovary was not sufficient to induce full parthenocarpy.

  9. Gibberellin as a factor in floral regulatory networks.

    PubMed

    Mutasa-Göttgens, Effie; Hedden, Peter

    2009-01-01

    Gibberellins (GAs) function not only to promote the growth of plant organs, but also to induce phase transitions during development. Their involvement in flower initiation in long-day (LD) and biennial plants is well established and there is growing insight into the mechanisms by which floral induction is achieved. The extent to which GAs mediate the photoperiodic stimulus to flowering in LD plants is, with a few exceptions, less clear. Despite evidence for photoperiod-enhanced GA biosynthesis in leaves of many LD plants, through up-regulation of GA 20-oxidase gene expression, a function for GAs as transmitted signals from leaves to apices in response to LD has been demonstrated only in Lolium species. In Arabidopsis thaliana, as one of four quantitative floral pathways, GA signalling has a relatively minor influence on flowering time in LD, while in SD, in the absence of the photoperiod flowering pathway, the GA pathway assumes a major role and becomes obligatory. Gibberellins promote flowering in Arabidopsis through the activation of genes encoding the floral integrators SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), LEAFY (LFY), and FLOWERING LOCUS T (FT) in the inflorescence and floral meristems, and in leaves, respectively. Although GA signalling is not required for floral organ specification, it is essential for the normal growth and development of these organs. The sites of GA production and action within flowers, and the signalling pathways involved are beginning to be revealed.

  10. Interplay of sugar, light and gibberellins in expression of Rosa hybrida vacuolar invertase 1 regulation.

    PubMed

    Rabot, Amélie; Portemer, Virginie; Péron, Thomas; Mortreau, Eric; Leduc, Nathalie; Hamama, Latifa; Coutos-Thévenot, Pierre; Atanassova, Rossitza; Sakr, Soulaiman; Le Gourrierec, José

    2014-10-01

    Our previous findings showed that the expression of the Rosa hybrida vacuolar invertase 1 gene (RhVI1) was tightly correlated with the ability of buds to grow out and was under sugar, gibberellin and light control. Here, we aimed to provide an insight into the mechanistic basis of this regulation. In situ hybridization showed that RhVI1 expression was localized in epidermal cells of young leaves of bursting buds. We then isolated a 895 bp fragment of the promoter of RhVI1. In silico analysis identified putative cis-elements involved in the response to sugars, light and gibberellins on its proximal part (595 bp). To carry out functional analysis of the RhVI1 promoter in a homologous system, we developed a direct method for stable transformation of rose cells. 5' deletions of the proximal promoter fused to the uidA reporter gene were inserted into the rose cell genome to study the cell's response to exogenous and endogenous stimuli. Deletion analysis revealed that the 468 bp promoter fragment is sufficient to trigger reporter gene activity in response to light, sugars and gibberellins. This region confers sucrose- and fructose-, but not glucose-, responsive activation in the dark. Inversely, the -595 to -468 bp region that carries the sugar-repressive element (SRE) is required to down-regulate the RhVI1 promoter in response to sucrose and fructose in the dark. We also demonstrate that sugar/light and gibberellin/light act synergistically to up-regulate β-glucuronidase (GUS) activity sharply under the control of the 595 bp pRhVI1 region. These results reveal that the 127 bp promoter fragment located between -595 and -468 bp is critical for light and sugar and light and gibberellins to act synergistically.

  11. Incorporation of Socio-scientific Content into Active Learning Activities

    NASA Astrophysics Data System (ADS)

    King, D. B.; Lewis, J. E.; Anderson, K.; Latch, D.; Sutheimer, S.; Webster, G.; Moog, R.

    2014-12-01

    Active learning has gained increasing support as an effective pedagogical technique to improve student learning. One way to promote active learning in the classroom is the use of in-class activities in place of lecturing. As part of an NSF-funded project, a set of in-class activities have been created that use climate change topics to teach chemistry content. These activities use the Process Oriented Guided Inquiry Learning (POGIL) methodology. In this pedagogical approach a set of models and a series of critical thinking questions are used to guide students through the introduction to or application of course content. Students complete the activities in their groups, with the faculty member as a facilitator of learning. Through assigned group roles and intentionally designed activity structure, process skills, such as teamwork, communication, and information processing, are developed during completion of the activity. Each of these climate change activities contains a socio-scientific component, e.g., social, ethical and economic data. In one activity, greenhouse gases are used to explain the concept of dipole moment. Data about natural and anthropogenic production rates, global warming potential and atmospheric lifetimes for a list of greenhouse gases are presented. The students are asked to identify which greenhouse gas they would regulate, with a corresponding explanation for their choice. They are also asked to identify the disadvantages of regulating the gas they chose in the previous question. In another activity, where carbon sequestration is used to demonstrate the utility of a phase diagram, students use economic and environmental data to choose the best location for sequestration. Too often discussions about climate change (both in and outside the classroom) consist of purely emotional responses. These activities force students to use data to support their arguments and hypothesize about what other data could be used in the corresponding discussion to

  12. Over-expression of a gibberellin 2-oxidase gene from Phaseolus coccineus L. enhances gibberellin inactivation and induces dwarfism in Solanum species.

    PubMed

    Dijkstra, C; Adams, E; Bhattacharya, A; Page, A F; Anthony, P; Kourmpetli, S; Power, J B; Lowe, K C; Thomas, S G; Hedden, P; Phillips, A L; Davey, M R

    2008-03-01

    Gibberellins (GAs) are endogenous hormones that play a predominant role in regulating plant stature by increasing cell division and elongation in stem internodes. The product of the GA 2-oxidase gene from Phaseolus coccineus (PcGA2ox1) inactivates C(19)-GAs, including the bioactive GAs GA(1 )and GA(4), by 2beta-hydroxylation, reducing the availability of these GAs in plants. The PcGA2ox1 gene was introduced into Solanum melanocerasum and S. nigrum (Solanaceae) by Agrobacterium-mediated transformation with the aim of decreasing the amounts of bioactive GA in these plants and thereby reducing their stature. The transgenic plants exhibited a range of dwarf phenotypes associated with a severe reduction in the concentrations of the biologically active GA(1) and GA(4). Flowering and fruit development were unaffected. The transgenic plants contained greater concentrations of chlorophyll b (by 88%) and total chlorophyll (11%), although chlorophyll a and carotenoid contents were reduced by 8 and 50%, respectively. This approach may provide an alternative to the application of chemical growth retardants for reducing the stature of plants, particularly ornamentals, in view of concerns over the potential environmental and health hazards of such compounds.

  13. Natural Variation of Molecular and Morphological Gibberellin Responses1[OPEN

    PubMed Central

    Herman, Dorota; Kojima, Mikiko; Van Daele, Twiggy; Sakakibara, Hitoshi

    2017-01-01

    Although phytohormones such as gibberellins are essential for many conserved aspects of plant physiology and development, plants vary greatly in their responses to these regulatory compounds. Here, we use genetic perturbation of endogenous gibberellin levels to probe the extent of intraspecific variation in gibberellin responses in natural accessions of Arabidopsis (Arabidopsis thaliana). We find that these accessions vary greatly in their ability to buffer the effects of overexpression of GA20ox1, encoding a rate-limiting enzyme for gibberellin biosynthesis, with substantial differences in bioactive gibberellin concentrations as well as transcriptomes and growth trajectories. These findings demonstrate a surprising level of flexibility in the wiring of regulatory networks underlying hormone metabolism and signaling. PMID:27879393

  14. Detection of endogenous gibberellins and their relationship to hypocotyl elongation in soybean seedlings

    SciTech Connect

    Bensen, R.J.; Beall, F.D.; Mullet, J.E.; Morgan, P.W. )

    1990-09-01

    Four gibberellins, GA{sub 53}, GA{sub 19}, GA{sub 20}, and GA{sub 1}, were detected by bioassay, chromatography in two HPLC systems, and combined gas chromatography-mass spectroscopy-selected ion monitoring (GC-MS-SIM) in etiolated soybean (Glycine max (L.) Merr.) hypocotyls. GC-MS-SIM employed ({sup 2}H{sub 2})-labeled standards for each endogenous gibberellin detected, and quantities estimated from bioassays and GC-MS-SIM were similar. This result plus the tentative detection of GA{sub 44} and GA{sub 8} (standards not available) indicates that the early-C-13-hydroxylation pathway for gibberellin biosynthesis predominates in soybean hypocotyls. Other gibberellins were not detected. Growth rates decreased after transfer to low water potential ({psi}{sub w}) vermiculite and were completely arrested 24 hours after transfer. The GA{sub 1} content in the elongating region of hypocotyls had declined to 38% of the 0 time value at 24 hours after transfer to low {psi}{sub w} vermiculite, a level which was only 13% of the GA{sub 1} content in control seedlings at the same time (24 hours posttransfer). Seedlings were growth responsive to exogenous GA{sub 3}, and this GA{sub 3}-promoted growth was inhibited by exogenous ABA. The data are consistent with the hypothesis that changes in GA{sub 1} and ABA levels play a role in adjusting hypocotyl elongation rates. However, the changes observed are not of sufficient magnitude nor do they occur rapidly enough to suggest they are the primary regulators of elongation rate responses to rapidly changing plant water status.

  15. Chemical screening and development of novel gibberellin mimics.

    PubMed

    Jiang, Kai; Shimotakahara, Hiroaki; Luo, Ming; Otani, Masato; Nakamura, Hidemitsu; Moselhy, Said Salama; Abualnaja, Khalid Omer; Al-Malki, Abdulrahman Labeed; Kumosani, Taha Abduallah; Kitahata, Nobutaka; Nakano, Takeshi; Nakajima, Masatoshi; Asami, Tadao

    2017-08-15

    Gibberellin (GA) plays versatile roles in the regulation of plant growth and development and therefore is widely used as a regulator in agriculture. We performed a chemical library screening and identified a chemical, named 67D, as a stimulator of seed germination that was suppressed by paclobutrazol (PAC), a GA biosynthesis inhibitor. In vitro binding assays indicated that 67D binds to the GID1 receptor. Further studies on the structure-activity relationship identified a chemical, named chemical 6, that strongly promoted seed germination suppressed by PAC. Chemical 6 was further confirmed to promote the degradation of RGA (for repressor of ga1-3), a DELLA protein, and suppress the expression levels of GA3ox1 in the same manner as GA does. 67D and its analogs are supposed to be agonists of GID1 and are expected to be utilized in agriculture and basic research as an alternative to GA. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Gibberellins - a multifaceted hormone in plant growth regulatory network.

    PubMed

    Gantait, Saikat; Sinniah, Uma Rani; Ali, Md Nasim; Sahu, Narayan Chandra

    2015-01-01

    Plants tend to acclimatize to unfavourable environs by integrating growth and development to environmentally activated signals. Phytohormones strongly regulate convergent developmental and stress adaptive procedures and synchronize cellular reaction to the exogenous and endogenous conditions within the adaptive signaling networks. Gibberellins (GA), a group of tetracyclic diterpenoids, being vital regulators of plant growth, are accountable for regulating several aspects of growth and development of higher plants. If the element of reproduction is considered as an absolute requisite then for a majority of the higher plants GA signaling is simply indispensable. Latest reports have revealed unique conflicting roles of GA and other phytohormones in amalgamating growth and development in plants through environmental signaling. Numerous physiological researches have detailed substantial crosstalk between GA and other hormones like abscisic acid, auxin, cytokinin, and jasmonic acid. In this review, a number of explanations and clarifications for this discrepancy are explored based on the crosstalk among GA and other phytohormones.

  17. Mechanisms of signaling crosstalk between brassinosteroids and gibberellins

    PubMed Central

    Li, Qian-Feng; He, Jun-Xian

    2013-01-01

    Brassinosteroids (BRs) and Gibberellins (GAs) are two principal groups of growth-promoting phytohormones. Accumulating evidence supports that there are crosstalks between BR and GA signaling pathways. However, a molecular mechanism for direct signaling crosstalk between BRs and GAs was not revealed until recently. Works from three different groups demonstrated that an interaction between BZR1/BES1 and DELLAs, two groups of key transcriptional regulators from the BR and GA signaling pathways, respectively, mediates the direct signaling crosstalk between BRs and GAs in controlling cell elongation in Arabidopsis. It was shown that DELLA proteins not only affect the protein stability but also inhibit the transcriptional activity of BZR1. Thus, GAs promote cell elongation, at least in part, through releasing DELLA-mediated inhibition of BZR1. This review aims to introduce these recent advances in our understanding of how BRs and GAs coordinate to regulate plant growth and development at the molecular level. PMID:23603943

  18. Mechanisms of signaling crosstalk between brassinosteroids and gibberellins.

    PubMed

    Li, Qian-Feng; He, Jun-Xian

    2013-07-01

    Brassinosteroids (BRs) and Gibberellins (GAs) are two principal groups of growth-promoting phytohormones. Accumulating evidence supports that there are crosstalks between BR and GA signaling pathways. However, a molecular mechanism for direct signaling crosstalk between BRs and GAs was not revealed until recently. Works from three different groups demonstrated that an interaction between BZR1/BES1 and DELLAs, two groups of key transcriptional regulators from the BR and GA signaling pathways, respectively, mediates the direct signaling crosstalk between BRs and GAs in controlling cell elongation in Arabidopsis. It was shown that DELLA proteins not only affect the protein stability but also inhibit the transcriptional activity of BZR1. Thus, GAs promote cell elongation, at least in part, through releasing DELLA-mediated inhibition of BZR1. This review aims to introduce these recent advances in our understanding of how BRs and GAs coordinate to regulate plant growth and development at the molecular level.

  19. Gibberellin 3-oxidase gene expression patterns influence gibberellin biosynthesis, growth, and development in pea.

    PubMed

    Reinecke, Dennis M; Wickramarathna, Aruna D; Ozga, Jocelyn A; Kurepin, Leonid V; Jin, Alena L; Good, Allen G; Pharis, Richard P

    2013-10-01

    Gibberellins (GAs) are key modulators of plant growth and development. PsGA3ox1 (LE) encodes a GA 3β-hydroxylase that catalyzes the conversion of GA20 to biologically active GA1. To further clarify the role of GA3ox expression during pea (Pisum sativum) plant growth and development, we generated transgenic pea lines (in a lele background) with cauliflower mosaic virus-35S-driven expression of PsGA3ox1 (LE). PsGA3ox1 transgene expression led to higher GA1 concentrations in a tissue-specific and development-specific manner, altering GA biosynthesis and catabolism gene expression and plant phenotype. PsGA3ox1 transgenic plants had longer internodes, tendrils, and fruits, larger stipules, and displayed delayed flowering, increased apical meristem life, and altered vascular development relative to the null controls. Transgenic PsGA3ox1 overexpression lines were then compared with lines where endogenous PsGA3ox1 (LE) was introduced, by a series of backcrosses, into the same genetic background (BC LEle). Most notably, the BC LEle plants had substantially longer internodes containing much greater GA1 levels than the transgenic PsGA3ox1 plants. Induction of expression of the GA deactivation gene PsGA2ox1 appears to make an important contribution to limiting the increase of internode GA1 to modest levels for the transgenic lines. In contrast, PsGA3ox1 (LE) expression driven by its endogenous promoter was coordinated within the internode tissue to avoid feed-forward regulation of PsGA2ox1, resulting in much greater GA1 accumulation. These studies further our fundamental understanding of the regulation of GA biosynthesis and catabolism at the tissue and organ level and demonstrate that the timing/localization of GA3ox expression within an organ affects both GA homeostasis and GA1 levels, and thereby growth.

  20. Immunomodulation of bioactive gibberellin confers gibberellin-deficient phenotypes in plants.

    PubMed

    Suzuki, Yoshihito; Mizuno, Toru; Urakami, Eriko; Yamaguchi, Isomaro; Asami, Tadao

    2008-05-01

    Immunomodulation is a means to modulate an organism's function by antibody production to capture either endogenous or exogenous antigens. This method was applied to plants to repress the function of gibberellins (GAs), a class of phytohormones responsible for plant elongation, by anti-bioactive GA antibodies. Two different antibodies were produced in Arabidopsis as single-chain variable fragment (scFv) fused to green fluorescent protein (GFP) with four different subcellular localizations: endoplasmic reticulum (ER), cytosol, apoplastic space or the outer surface of the plasma membrane. When targeting scFv-GFP to ER, plants showed the highest accumulation of scFv-GFP, with binding activity, strong GFP fluorescence in ER-derived compartments and mild but clear GA-deficient phenotypes, including a smaller leaf size, delayed bolting, shorter inflorescence length and decreased germination. Plants expressing scFv-GFP in ER responded to exogenous GA(4) and contained 15-40 times greater endogenous GA(4) than wild-type plants. They also showed increased gene expression for GA3ox1, GA20ox1 and GA20ox2, but decreased expression for GA2ox1, which are feedback and feedforward regulated by GA signalling, respectively. These results suggest that the level of free functional GA(4) decreased when trapped in the ER with scFv to the extent that mild GA-deficient phenotypes were created. A dramatic increase in the total sum of GA(4) (free plus scFv-GFP bound) was detected as a result of the up-regulation of GA biosynthesis (feedback regulated), and a decrease in GA(4) catabolism as a result of protection by scFv-GFP binding. This study demonstrates that the use of immunomodulation to inhibit the action of bioactive GAs is an effective method of creating GA-deficient plants.

  1. Characterization of CYP115 As a Gibberellin 3-Oxidase Indicates That Certain Rhizobia Can Produce Bioactive Gibberellin A4.

    PubMed

    Nett, Ryan S; Contreras, Tiffany; Peters, Reuben J

    2017-02-16

    The gibberellin (GA) phytohormones are produced not only by plants but also by fungi and bacteria. Previous characterization of a cytochrome P450 (CYP)-rich GA biosynthetic operon found in many symbiotic, nitrogen-fixing rhizobia led to the elucidation of bacterial GA biosynthesis and implicated GA9 as the final product. However, GA9 does not exhibit hormonal/biological activity and presumably requires further transformation to elicit an effect in the legume host plant. Some rhizobia that contain the GA operon also possess an additional CYP (CYP115), and here we show that this acts as a GA 3-oxidase to produce bioactive GA4 from GA9. This is the first GA 3-oxidase identified for rhizobia, and provides a more complete scheme for biosynthesis of bioactive GAs in bacteria. Furthermore, phylogenetic analyses suggest that rhizobia acquired CYP115 independently of the core GA operon, adding further complexity to the horizontal gene transfer of GA biosynthetic enzymes among bacteria.

  2. A Gibberellin-Mediated DELLA-NAC Signaling Cascade Regulates Cellulose Synthesis in Rice[OPEN

    PubMed Central

    Huang, Debao; Wang, Shaogan; Zhang, Baocai; Shang-Guan, Keke; Shi, Yanyun; Zhang, Dongmei; Liu, Xiangling; Wu, Kun; Xu, Zuopeng; Fu, Xiangdong; Zhou, Yihua

    2015-01-01

    Cellulose, which can be converted into numerous industrial products, has important impacts on the global economy. It has long been known that cellulose synthesis in plants is tightly regulated by various phytohormones. However, the underlying mechanism of cellulose synthesis regulation remains elusive. Here, we show that in rice (Oryza sativa), gibberellin (GA) signals promote cellulose synthesis by relieving the interaction between SLENDER RICE1 (SLR1), a DELLA repressor of GA signaling, and NACs, the top-layer transcription factors for secondary wall formation. Mutations in GA-related genes and physiological treatments altered the transcription of CELLULOSE SYNTHASE genes (CESAs) and the cellulose level. Multiple experiments demonstrated that transcription factors NAC29/31 and MYB61 are CESA regulators in rice; NAC29/31 directly regulates MYB61, which in turn activates CESA expression. This hierarchical regulation pathway is blocked by SLR1-NAC29/31 interactions. Based on the results of anatomical analysis and GA content examination in developing rice internodes, this signaling cascade was found to be modulated by varied endogenous GA levels and to be required for internode development. Genetic and gene expression analyses were further performed in Arabidopsis thaliana GA-related mutants. Altogether, our findings reveal a conserved mechanism by which GA regulates secondary wall cellulose synthesis in land plants and provide a strategy for manipulating cellulose production and plant growth. PMID:26002868

  3. Ectopic expression of EFFECTOR OF TRANSCRIPTION perturbs gibberellin-mediated plant developmental processes.

    PubMed

    Ellerström, M; Reidt, W; Ivanov, R; Tiedemann, J; Melzer, M; Tewes, A; Moritz, T; Mock, H-P; Sitbon, F; Rask, L; Bäumlein, H

    2005-11-01

    The plant hormone gibberellin (GA) is known to modulate various aspects of plant cell differentiation and development. The current model of GA-mediated regulation is based on a de-repressible system and includes specific protein modification and degradation. HRT, a zinc finger protein from barley has been shown to have GA-dependent transcriptional repressing activity on the seed-specific alpha-amylase promoter [Raventos, D., Skriver, K., Schlein, M., Karnahl, K., Rogers, S.W., Rogers, J.C. and Mundy, J. 1998. J. Biol. Chem. 273: 23313-23320]. Here we report the characterization of a dicot homologue from Brassica napus (BnET) and provide evidence for its role in GA response modulation suggesting that this could be a conserved feature of this gene family. When BnET is ectopically expressed in either Arabidopsis or tobacco the phenotypes include dwarfism due to shorter internodes and late flowering, reduced germination rate, increased anthocyanin content and reduced xylem lignification as a marker for terminal cell differentiation. Transient expression in protoplasts supports the notion that this most likely is due to a transcriptional repression of GA controlled genes. Finally, histological analysis showed that in contrast to other GA deficient mutants the shorter internodes were due to fewer but not smaller cells, suggesting a function of BnET in GA-mediated cell division control.

  4. Gibberellin Overproduction Promotes Sucrose Synthase Expression and Secondary Cell Wall Deposition in Cotton Fibers

    PubMed Central

    Zhao, Juan; Song, Shui-Qing; Hu, Lin; Zeng, Jian-Yan; Li, Xian-Bi; Hou, Lei; Luo, Ming; Li, De-Mou; Pei, Yan

    2014-01-01

    Bioactive gibberellins (GAs) comprise an important class of natural plant growth regulators and play essential roles in cotton fiber development. To date, the molecular base of GAs' functions in fiber development is largely unclear. To address this question, the endogenous bioactive GA levels in cotton developing fibers were elevated by specifically up-regulating GA 20-oxidase and suppressing GA 2-oxidase via transgenic methods. Higher GA levels in transgenic cotton fibers significantly increased micronaire values, 1000-fiber weight, cell wall thickness and cellulose contents of mature fibers. Quantitative RT-PCR and biochemical analysis revealed that the transcription of sucrose synthase gene GhSusA1 and sucrose synthase activities were significantly enhanced in GA overproducing transgenic fibers, compared to the wild-type cotton. In addition, exogenous application of bioactive GA could promote GhSusA1 expression in cultured fibers, as well as in cotton hypocotyls. Our results suggested that bioactive GAs promoted secondary cell wall deposition in cotton fibers by enhancing sucrose synthase expression. PMID:24816840

  5. Mechanism of gibberellin-dependent stem elongation in peas

    NASA Technical Reports Server (NTRS)

    Cosgrove, D. J.; Sovonick-Dunford, S. A.

    1989-01-01

    Stem elongation in peas (Pisum sativum L.) is under partial control by gibberellins, yet the mechanism of such control is uncertain. In this study, we examined the cellular and physical properties that govern stem elongation, to determine how gibberellins influence pea stem growth. Stem elongation of etiolated seedlings was retarded with uniconozol, a gibberellin synthesis inhibitor, and the growth retardation was reversed by exogenous gibberellin. Using the pressure probe and vapor pressure osmometry, we found little effect of uniconozol and gibberellin on cell turgor pressure or osmotic pressure. In contrast, these treatments had major effects on in vivo stress relaxation, measured by turgor relaxation and pressure-block techniques. Uniconozol-treated plants exhibited reduced wall relaxation (both initial rate and total amount). The results show that growth retardation is effected via a reduction in the wall yield coefficient and an increase in the yield threshold. These effects were largely reversed by exogenous gibberellin. When we measured the mechanical characteristics of the wall by stress/strain (Instron) analysis, we found only minor effects of uniconozol and gibberellin on the plastic compliance. This observation indicates that these agents did not alter wall expansion through effects on the mechanical (viscoelastic) properties of the wall. Our results suggest that wall expansion in peas is better viewed as a chemorheological, rather than a viscoelastic, process.

  6. Mechanism of gibberellin-dependent stem elongation in peas

    NASA Technical Reports Server (NTRS)

    Cosgrove, D. J.; Sovonick-Dunford, S. A.

    1989-01-01

    Stem elongation in peas (Pisum sativum L.) is under partial control by gibberellins, yet the mechanism of such control is uncertain. In this study, we examined the cellular and physical properties that govern stem elongation, to determine how gibberellins influence pea stem growth. Stem elongation of etiolated seedlings was retarded with uniconozol, a gibberellin synthesis inhibitor, and the growth retardation was reversed by exogenous gibberellin. Using the pressure probe and vapor pressure osmometry, we found little effect of uniconozol and gibberellin on cell turgor pressure or osmotic pressure. In contrast, these treatments had major effects on in vivo stress relaxation, measured by turgor relaxation and pressure-block techniques. Uniconozol-treated plants exhibited reduced wall relaxation (both initial rate and total amount). The results show that growth retardation is effected via a reduction in the wall yield coefficient and an increase in the yield threshold. These effects were largely reversed by exogenous gibberellin. When we measured the mechanical characteristics of the wall by stress/strain (Instron) analysis, we found only minor effects of uniconozol and gibberellin on the plastic compliance. This observation indicates that these agents did not alter wall expansion through effects on the mechanical (viscoelastic) properties of the wall. Our results suggest that wall expansion in peas is better viewed as a chemorheological, rather than a viscoelastic, process.

  7. Mechanism of gibberellin-dependent stem elongation in peas.

    PubMed

    Cosgrove, D J; Sovonick-Dunford, S A

    1989-01-01

    Stem elongation in peas (Pisum sativum L.) is under partial control by gibberellins, yet the mechanism of such control is uncertain. In this study, we examined the cellular and physical properties that govern stem elongation, to determine how gibberellins influence pea stem growth. Stem elongation of etiolated seedlings was retarded with uniconozol, a gibberellin synthesis inhibitor, and the growth retardation was reversed by exogenous gibberellin. Using the pressure probe and vapor pressure osmometry, we found little effect of uniconozol and gibberellin on cell turgor pressure or osmotic pressure. In contrast, these treatments had major effects on in vivo stress relaxation, measured by turgor relaxation and pressure-block techniques. Uniconozol-treated plants exhibited reduced wall relaxation (both initial rate and total amount). The results show that growth retardation is effected via a reduction in the wall yield coefficient and an increase in the yield threshold. These effects were largely reversed by exogenous gibberellin. When we measured the mechanical characteristics of the wall by stress/strain (Instron) analysis, we found only minor effects of uniconozol and gibberellin on the plastic compliance. This observation indicates that these agents did not alter wall expansion through effects on the mechanical (viscoelastic) properties of the wall. Our results suggest that wall expansion in peas is better viewed as a chemorheological, rather than a viscoelastic, process.

  8. Advertising content in physical activity print materials.

    PubMed

    Cardinal, Bradley J

    2002-01-01

    Copies of 80 sets of print materials available free of charge to the general public were analyzed to determine the relationship between the developer and advertising-related material. Almost all of the materials had some form of advertising content. Materials from commercial product vendors were most likely to have product logos, references to specific brands, and had the greatest number of logos, and the greatest number of references to specific brands. They were the second most likely to have advertising slogans, and had the second greatest number of advertising slogans.

  9. Carbohydrates and gibberellins relationship in potato tuberization.

    PubMed

    Ševčíková, Hana; Mašková, Petra; Tarkowská, Danuše; Mašek, Tomáš; Lipavská, Helena

    2017-07-01

    Potato represents the third most important crop worldwide and therefore to understand regulations of tuber onset is crucial from both theoretical and practical points of view. Photosynthesis and related carbohydrate status along with phytohormone balance belong to the essential factors in regulation of plant development including storage organ formation. In our work we used potato (Solanum tuberosum) cv. Lada and its spontaneously tuberizing mutant (ST plants) grown in vitro under low carbohydrate availability (non-inductive conditions). Small plant phenotype and readiness to tuberization of ST plants was, however, not accompanied by lower gibberellins levels, as determined by UHPLC-MS/MS. Therefore, we focused on the other inducing factor, carbohydrate status. Using HPLC, we followed changes in carbohydrate distribution under mixotrophic (2.5% sucrose in medium) and photoautotrophic conditions (no sucrose addition and higher gas and light availability) and observed changes in soluble carbohydrate allocation and starch deposition, favouring basal stem part in mutants. In addition, the determination of tuber-inducing marker gene expressions revealed increased levels of StSP6A in ST leaves. Collectively these data point towards the possibility of two parallel cross-talking pathways (carbohydrate - and gibberellin- dependent ones) with the power of both to outcompete the other one when its signal is for some reason extraordinary strong. Copyright © 2017 Elsevier GmbH. All rights reserved.

  10. Gibberellin homeostasis and plant height control by EUI and a role for gibberellin in root gravity responses in rice.

    PubMed

    Zhang, Yingying; Zhu, Yongyou; Peng, Yu; Yan, Dawei; Li, Qun; Wang, Jianjun; Wang, Linyou; He, Zuhua

    2008-03-01

    The rice Eui (ELONGATED UPPERMOST INTERNODE) gene encodes a cytochrome P450 monooxygenase that deactivates bioactive gibberellins (GAs). In this study, we investigated controlled expression of the Eui gene and its role in plant development. We found that Eui was differentially induced by exogenous GAs and that the Eui promoter had the highest activity in the vascular bundles. The eui mutant was defective in starch granule development in root caps and Eui overexpression enhanced starch granule generation and gravity responses, revealing a role for GA in root starch granule development and gravity responses. Experiments using embryoless half-seeds revealed that RAmy1A and GAmyb were highly upregulated in eui aleurone cells in the absence of exogenous GA. In addition, the GA biosynthesis genes GA3ox1 and GA20ox2 were downregulated and GA2ox1 was upregulated in eui seedlings. These results indicate that EUI is involved in GA homeostasis, not only in the internodes at the heading stage, but also in the seedling stage, roots and seeds. Disturbing GA homeostasis affected the expression of the GA signaling genes GID1 (GIBBERELLIN INSENSITIVE DWARF 1), GID2 and SLR1. Transgenic RNA interference of the Eui gene effectively increased plant height and improved heading performance. By contrast, the ectopic expression of Eui under the promoters of the rice GA biosynthesis genes GA3ox2 and GA20ox2 significantly reduced plant height. These results demonstrate that a slight increase in Eui expression could dramatically change rice morphology, indicating the practical application of the Eui gene in rice molecular breeding for a high yield potential.

  11. Role of reactive oxygen species produced by NADPH oxidase in gibberellin biosynthesis during barley seed germination.

    PubMed

    Kai, Kyohei; Kasa, Shinsuke; Sakamoto, Masatsugu; Aoki, Nozomi; Watabe, Gaku; Yuasa, Takashi; Iwaya-Inoue, Mari; Ishibashi, Yushi

    2016-05-03

    NADPH oxidase catalyzes the production of the superoxide anion (O2(-)), a reactive oxygen species (ROS), and regulates the germination of barley (Hordeum vulgare L.). Diphenyleneiodonium (DPI) chloride, an NADPH oxidase inhibitor, delayed barley germination, and exogenous H2O2 (an ROS) partially rescued it. Six enzymes, ent-copalyl diphosphate synthase (CPS), ent-kaurene synthase (KS), ent-kaurene oxidase (KO), ent-kaurenoic acid oxidase (KAO), GA20-oxidase (GA20ox) and GA3-oxidase (GA3ox), catalyze the transformation of trans-geranylgeranyl diphosphate to active gibberellin, which promotes germination. Exogenous H2O2 promoted the expressions of HvKAO1 and HvGA3ox1 in barley embryos. These results suggest that ROS produced by NADPH oxidase are involved in gibberellin biosynthesis through the regulation of HvKAO1 and HvGA3ox1.

  12. Inhibition of gibberellin-induced elongation growth of rice by feruloyl oligosaccharides.

    PubMed

    Ishii, T; Nishijima, T

    1995-12-01

    The biological activity of cell wall-derived feruloyl oligosaccharides was investigated using a modified micro-drop bioassay. A feruloyl arabinoxylan trisaccharide (FAXX) and a feruloyl arabinoxylan tetrasaccharide (FAXXX) were found to inhibit the gibberellin-induced elongation of dwarf rice (Oryza sativa L., cv, Tan-ginbozu) that had been treated with uniconazole (S-3307), an inhibitor of the biosynthesis of gibberellins. An arabinoxylan trisaccharide (AXX) was ineffective. The growth-inhibitory effect of feruloyl oligosaccharides depended on their feruloyl and glycosyl moieties. The amount of esterified diferulic acid residues in the cell walls of the second leaf sheath of rice seedlings that had been treated with FAXX was almost same as that of controls. Feruloyl oligosaccharides did not inhibit the incorporation of [14C]leucine into acid-precipitable proteins by suspension-cultured maize cells, whereas cinnamic acid and its derivatives strongly inhibited such incorporation.

  13. The Nitrate Content of Greenland Ice and Solar Activity

    NASA Astrophysics Data System (ADS)

    Kocharov, G. E.; Kudryavtsev, I. V.; Ogurtsov, M. G.; Sonninen, E.; Jungner, H.

    2000-12-01

    Past solar activity is studied based on analysis of data on the nitrate content of Greenland ice in the period from 1576 1991. Hundred-year (over the entire period) and quasi-five-year (in the middle of the 18th century) variations in the nitrate content are detected. These reflect the secular solar-activity cycle and cyclicity in the flare activity of the Sun.

  14. Gibberellins and gravitropism in maize shoots: endogenous gibberellin-like substances and movement and metabolism of [3H]Gibberellin A20

    NASA Technical Reports Server (NTRS)

    Rood, S. B.; Kaufman, P. B.; Abe, H.; Pharis, R. P.

    1987-01-01

    [3H]Gibberellin A20 (GA20) of high specific radioactivity (49.9 gigabecquerel per millimole) was applied equilaterally in a ring of microdrops to the internodal pulvinus of shoots of 3-week-old gravistimulated and vertical normal maize (Zea mays L.), and to a pleiogravitropic (prostrate) maize mutant, lazy (la). All plants converted the [3H]GA20 to [3H]GA1- and [3H]GA29-like metabolites as well as to several metabolites with the partitioning and chromatographic behavior of glucosyl conjugates of [3H]GA1, [3H]GA29, and [3H]GA8. The tentative identification of these putative [3H]GA glucosyl conjugates was further supported by the release of the free [3H]GA moiety after cleavage with cellulase. Within 12 hours of the [3H]GA20 feed, there was a significantly higher proportion of total radioactivity in lower than in upper halves of internode and leaf sheath pulvini in gravistimulated normal maize. Further, there was a significantly higher proportion of putative free GA metabolites of [3H]GA20, especially [3H]GA1, in the lower halves of normal maize relative to upper halves. The differential localization of the metabolites between upper and lower halves was not apparent in the pleiogravitropic mutant, la. Endogenous GA-like substances were also examined in gravistimulated maize shoots. Forty-eight hours after gravistimulation of 3-week-old maize seedlings, endogenous free GA-like substances in upper and lower leaf sheath and internode pulvini halves were extracted, chromatographed, and bioassayed using the "Tanginbozu" dwarf rice microdrop assay. Lower halves contained consistently higher total levels of GA-like activity. The qualitative elution profile of GA-like substances differed consistently, upper halves containing principally a GA20-like substance and lower halves containing principally a GA20-like substance and lower halves containing mainly GA1-like and GA19-like substances. Gibberellins A1 (10 nanograms per gram) and A20 (5 nanograms per gram) were identified

  15. Gibberellins and gravitropism in maize shoots: endogenous gibberellin-like substances and movement and metabolism of [3H]Gibberellin A20

    NASA Technical Reports Server (NTRS)

    Rood, S. B.; Kaufman, P. B.; Abe, H.; Pharis, R. P.

    1987-01-01

    [3H]Gibberellin A20 (GA20) of high specific radioactivity (49.9 gigabecquerel per millimole) was applied equilaterally in a ring of microdrops to the internodal pulvinus of shoots of 3-week-old gravistimulated and vertical normal maize (Zea mays L.), and to a pleiogravitropic (prostrate) maize mutant, lazy (la). All plants converted the [3H]GA20 to [3H]GA1- and [3H]GA29-like metabolites as well as to several metabolites with the partitioning and chromatographic behavior of glucosyl conjugates of [3H]GA1, [3H]GA29, and [3H]GA8. The tentative identification of these putative [3H]GA glucosyl conjugates was further supported by the release of the free [3H]GA moiety after cleavage with cellulase. Within 12 hours of the [3H]GA20 feed, there was a significantly higher proportion of total radioactivity in lower than in upper halves of internode and leaf sheath pulvini in gravistimulated normal maize. Further, there was a significantly higher proportion of putative free GA metabolites of [3H]GA20, especially [3H]GA1, in the lower halves of normal maize relative to upper halves. The differential localization of the metabolites between upper and lower halves was not apparent in the pleiogravitropic mutant, la. Endogenous GA-like substances were also examined in gravistimulated maize shoots. Forty-eight hours after gravistimulation of 3-week-old maize seedlings, endogenous free GA-like substances in upper and lower leaf sheath and internode pulvini halves were extracted, chromatographed, and bioassayed using the "Tanginbozu" dwarf rice microdrop assay. Lower halves contained consistently higher total levels of GA-like activity. The qualitative elution profile of GA-like substances differed consistently, upper halves containing principally a GA20-like substance and lower halves containing principally a GA20-like substance and lower halves containing mainly GA1-like and GA19-like substances. Gibberellins A1 (10 nanograms per gram) and A20 (5 nanograms per gram) were identified

  16. Gibberellins and gravitropism in maize shoots: endogenous gibberellin-like substances and movement and metabolism of [3H]Gibberellin A20.

    PubMed

    Rood, S B; Kaufman, P B; Abe, H; Pharis, R P

    1987-01-01

    [3H]Gibberellin A20 (GA20) of high specific radioactivity (49.9 gigabecquerel per millimole) was applied equilaterally in a ring of microdrops to the internodal pulvinus of shoots of 3-week-old gravistimulated and vertical normal maize (Zea mays L.), and to a pleiogravitropic (prostrate) maize mutant, lazy (la). All plants converted the [3H]GA20 to [3H]GA1- and [3H]GA29-like metabolites as well as to several metabolites with the partitioning and chromatographic behavior of glucosyl conjugates of [3H]GA1, [3H]GA29, and [3H]GA8. The tentative identification of these putative [3H]GA glucosyl conjugates was further supported by the release of the free [3H]GA moiety after cleavage with cellulase. Within 12 hours of the [3H]GA20 feed, there was a significantly higher proportion of total radioactivity in lower than in upper halves of internode and leaf sheath pulvini in gravistimulated normal maize. Further, there was a significantly higher proportion of putative free GA metabolites of [3H]GA20, especially [3H]GA1, in the lower halves of normal maize relative to upper halves. The differential localization of the metabolites between upper and lower halves was not apparent in the pleiogravitropic mutant, la. Endogenous GA-like substances were also examined in gravistimulated maize shoots. Forty-eight hours after gravistimulation of 3-week-old maize seedlings, endogenous free GA-like substances in upper and lower leaf sheath and internode pulvini halves were extracted, chromatographed, and bioassayed using the "Tanginbozu" dwarf rice microdrop assay. Lower halves contained consistently higher total levels of GA-like activity. The qualitative elution profile of GA-like substances differed consistently, upper halves containing principally a GA20-like substance and lower halves containing principally a GA20-like substance and lower halves containing mainly GA1-like and GA19-like substances. Gibberellins A1 (10 nanograms per gram) and A20 (5 nanograms per gram) were identified

  17. 'Green revolution' genes encode mutant gibberellin response modulators.

    PubMed

    Peng, J; Richards, D E; Hartley, N M; Murphy, G P; Devos, K M; Flintham, J E; Beales, J; Fish, L J; Worland, A J; Pelica, F; Sudhakar, D; Christou, P; Snape, J W; Gale, M D; Harberd, N P

    1999-07-15

    World wheat grain yields increased substantially in the 1960s and 1970s because farmers rapidly adopted the new varieties and cultivation methods of the so-called 'green revolution'. The new varieties are shorter, increase grain yield at the expense of straw biomass, and are more resistant to damage by wind and rain. These wheats are short because they respond abnormally to the plant growth hormone gibberellin. This reduced response to gibberellin is conferred by mutant dwarfing alleles at one of two Reduced height-1 (Rht-B1 and Rht-D1) loci. Here we show that Rht-B1/Rht-D1 and maize dwarf-8 (d8) are orthologues of the Arabidopsis Gibberellin Insensitive (GAI) gene. These genes encode proteins that resemble nuclear transcription factors and contain an SH2-like domain, indicating that phosphotyrosine may participate in gibberellin signalling. Six different orthologous dwarfing mutant alleles encode proteins that are altered in a conserved amino-terminal gibberellin signalling domain. Transgenic rice plants containing a mutant GAI allele give reduced responses to gibberellin and are dwarfed, indicating that mutant GAI orthologues could be used to increase yield in a wide range of crop species.

  18. Progress and development of analytical methods for gibberellins.

    PubMed

    Pan, Chaozhi; Tan, Swee Ngin; Yong, Jean Wan Hong; Ge, Liya

    2017-01-01

    Gibberellins, as a group of phytohormones, exhibit a wide variety of bio-functions within plant growth and development, which have been used to increase crop yields. Many analytical procedures, therefore, have been developed for the determination of the types and levels of endogenous and exogenous gibberellins. As plant tissues contain gibberellins in trace amounts (usually at the level of nanogram per gram fresh weight or even lower), the sample pre-treatment steps (extraction, pre-concentration, and purification) for gibberellins are reviewed in details. The primary focus of this comprehensive review is on the various analytical methods designed to meet the requirements for gibberellins analyses in complex matrices with particular emphasis on high-throughput analytical methods, such as gas chromatography, liquid chromatography, and capillary electrophoresis, mostly combined with mass spectrometry. The advantages and drawbacks of the each described analytical method are discussed. The overall aim of this review is to provide a comprehensive and critical view on the different analytical methods nowadays employed to analyze gibberellins in complex sample matrices and their foreseeable trends. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Gibberellin Concentration and Transport in Genetic Lines of Pea 1

    PubMed Central

    Proebsting, William M.; Hedden, Peter; Lewis, Mervyn J.; Croker, Stephen J.; Proebsting, Lena N.

    1992-01-01

    Effects of the Na and Le loci on gibberellin (GA) content and transport in pea (Pisum sativum L.) shoots were studied. GA1, GA8, GA17, GA19, GA20, GA29, GA44, GA8 catabolite, and GA29 catabolite were identified by full-scan gas chromatography-mass spectrometry in extracts of expanding and fully expanded tissues of line C79-338 (Na Le). Quantification of GAs by gas chromatography-single-ion monitoring using deuterated internal standards in lines differing at the Na and Le alleles showed that na reduced the contents of GA19, GA20, and GA29 on average to <3% and of GA1 and GA8 to <30% of those in corresponding Na lines. In expanding tissues from Na le lines, GA1 and GA8 concentrations were reduced to approximately 10 and 2%, respectively, and GA29 content increased 2- to 3-fold compared with those in Na Le plants. There was a close correlation between stem length and the concentrations of GA1 or GA8 in shoot apices in all six genotypes investigated. In na/Na grafts, internode length and GA1 concentration of nana scions were normalized, the GA20 content increased slightly, but GA19 levels were unaffected. Movement of labeled GAs applied to leaves on Na rootstocks indicated that GA19 was transported poorly to apices of na scions compared with GA20 and GA1. Our evidence suggests that GA20 is the major transported GA in peas. Images Figure 2 PMID:16653128

  20. The effect of carbon and nitrogen sources on auxins and gibberellin-like substances synthesis by bacteria isolated from the roots of pine seedlings (Pinus silvestris L).

    PubMed

    Pokojska-Burdziej, A

    1981-01-01

    It was found that in the presence of sodium succinate synthesis of auxins and gibberellin-like substances by microflora in the rhizosphere of pine seedlings was higher than in the presence of the other carbon sources. The smallest amounts of these substances were found in media with sodium pyruvate. The highest C-content (C:N = 60:1) was not optimal for the synthesis of plant growth regulators. Ammonia ions inhibited the production of gibberellin-like substances. The effect of different nitrogen sources and C:N ratio on the synthesis of auxins was different depending on bacterial strain used.

  1. Pheophorbide a Content and Chlorophyllase Activity in Green Tea.

    PubMed

    Kohata, K; Hanada, K; Yamauchi, Y; Horie, H

    1998-01-01

    We investigated the total content of pheophorbide a (PB a), which is sum of the contents of newly produced PB a, including PB a initially present and that converted from chlorophyllide a (Chd a) by the chlorophyllase reaction during incubation, in green tea samples, and found that the total content of PB a markedly increased in both Sencha and Matcha, compared with the initially present PB a content in each. This result demonstrates that chlorophyllase activity still remains in green tea, even after processing fresh green leaves. A comparison of the total contents of PB a produced during the incubation of chlorophyll a (Chl a) with Sencha and fresh green leaf acetone powder indicates that the ratio of chlorophyllase activity in Sencha and in fresh green leaves was about 1:20.

  2. In vitro bulb development in shallot (Allium cepa L. Aggregatum Group): effects of anti-gibberellins, sucrose and light.

    PubMed

    Le Guen-Le Saos, F; Hourmant, A; Esnault, F; Chauvin, J E

    2002-04-01

    Bulbing was studied in shallot plants cultured in vitro. Bulbing occurred under a 16 h photoperiod with fluorescent + incandescent light and 30-50 g 1(-1) sucrose in the culture medium. Exogenous gibberellin (10 microM GA3) inhibited leaf and root growth and bulbing. When added to the medium at a concentration of 10 microM, three inhibitors of gibberellin biosynthesis (ancymidol, flurprimidol and paclobutrazol) promoted bulb formation and the percentage of bulbing. When ancymidol was used in combination with GA3, it did not reverse the effect of GA3 applied alone. Under treatments with 30-70 g l(-1) sucrose, bulbing ratios greater than those found in control plants were achieved by addition of ancymidol, and bulb fresh weight was increased in the same way. Ancymidol caused a 66% decrease in sucrose content in leaf bases but greatly increased the glucose, fructose and fructan contents. The increase in fructan content by ancymidol could result from the three-fold rise in total [14C]sucrose uptake per plant from the culture medium associated with a marked increase in leaf base labelling at the expense of root labelling. The possible role of ancymidol is discussed and evidence supports a major regulatory role for gibberellins in bulbing.

  3. In vitro Bulb Development in Shallot (Allium cepa L. Aggregatum Group): Effects of Anti‐gibberellins, Sucrose and Light

    PubMed Central

    SAOS, F. LE GUEN‐LE; HOURMANT, A.; ESNAULT, F.; CHAUVIN, J. E.

    2002-01-01

    Bulbing was studied in shallot plants cultured in vitro. Bulbing occurred under a 16 h photoperiod with fluorescent + incandescent light and 30–50 g l–1 sucrose in the culture medium. Exogenous gibberellin (10 µm GA3) inhibited leaf and root growth and bulbing. When added to the medium at a concentration of 10 µm, three inhibitors of gibberellin biosynthesis (ancymidol, flurprimidol and paclobutrazol) promoted bulb formation and the percentage of bulbing. When ancymidol was used in combination with GA3, it did not reverse the effect of GA3 applied alone. Under treatments with 30–70 g l–1 sucrose, bulbing ratios greater than those found in control plants were achieved by addition of ancymidol, and bulb fresh weight was increased in the same way. Ancymidol caused a 66 % decrease in sucrose content in leaf bases but greatly increased the glucose, fructose and fructan contents. The increase in fructan content by ancymidol could result from the three‐fold rise in total [14C]sucrose uptake per plant from the culture medium associated with a marked increase in leaf base labelling at the expense of root labelling. The possible role of ancymidol is discussed and evidence supports a major regulatory role for gibberellins in bulbing. PMID:12096802

  4. Overexpression of Cotton GhMPK11 Decreases Disease Resistance through the Gibberellin Signaling Pathway in Transgenic Nicotiana benthamiana.

    PubMed

    Wang, Fang; Wang, Chen; Yan, Yan; Jia, Haihong; Guo, Xingqi

    2016-01-01

    Many changes in development, growth, hormone activity and environmental stimuli responses are mediated by mitogen-activated protein kinase (MAPK) cascades. However, in plants, studies on MAPKs have mainly focused on MPK3, MPK4 and MPK6. Here, a novel group B MAPK gene, GhMPK11, was isolated from cotton (Gossypium hirsutum L.) and characterized. Both promoter and expression pattern analyses revealed that GhMPK11 is involved in defense responses and signaling pathways. GhMPK11 overexpression in Nicotiana benthamiana plants could increase gibberellin 3 (GA3) content through the regulation of GA-related genes. Interestingly, either GhMPK11 overexpression or exogenous GA3 treatment in N. benthamiana plants could enhance the susceptibility of these plants to the infectious pathogens Ralstonia solanacearum and Rhizoctonia solani. Moreover, reactive oxygen species (ROS) accumulation was increased after pathogen infiltration due to the increased expression of ROS-related gene respiratory burst oxidative homologs (RbohB) and the decreased expression or activity of ROS detoxification enzymes regulated by GA3, such as superoxide dismutases (SODs), peroxidases (PODs), catalase (CAT) and glutathione S-transferase (GST). Taken together, these results suggest that GhMPK11 overexpression could enhance the susceptibility of tobacco to pathogen infection through the GA3 signaling pathway via down-regulation of ROS detoxification enzymes.

  5. Overexpression of Cotton GhMPK11 Decreases Disease Resistance through the Gibberellin Signaling Pathway in Transgenic Nicotiana benthamiana

    PubMed Central

    Wang, Fang; Wang, Chen; Yan, Yan; Jia, Haihong; Guo, Xingqi

    2016-01-01

    Many changes in development, growth, hormone activity and environmental stimuli responses are mediated by mitogen-activated protein kinase (MAPK) cascades. However, in plants, studies on MAPKs have mainly focused on MPK3, MPK4 and MPK6. Here, a novel group B MAPK gene, GhMPK11, was isolated from cotton (Gossypium hirsutum L.) and characterized. Both promoter and expression pattern analyses revealed that GhMPK11 is involved in defense responses and signaling pathways. GhMPK11 overexpression in Nicotiana benthamiana plants could increase gibberellin 3 (GA3) content through the regulation of GA-related genes. Interestingly, either GhMPK11 overexpression or exogenous GA3 treatment in N. benthamiana plants could enhance the susceptibility of these plants to the infectious pathogens Ralstonia solanacearum and Rhizoctonia solani. Moreover, reactive oxygen species (ROS) accumulation was increased after pathogen infiltration due to the increased expression of ROS-related gene respiratory burst oxidative homologs (RbohB) and the decreased expression or activity of ROS detoxification enzymes regulated by GA3, such as superoxide dismutases (SODs), peroxidases (PODs), catalase (CAT) and glutathione S-transferase (GST). Taken together, these results suggest that GhMPK11 overexpression could enhance the susceptibility of tobacco to pathogen infection through the GA3 signaling pathway via down-regulation of ROS detoxification enzymes. PMID:27242882

  6. Gene expression and metabolite profiling of gibberellin biosynthesis during induction of somatic embryogenesis in Medicago truncatula Gaertn

    PubMed Central

    Igielski, Rafał

    2017-01-01

    Gibberellins (GAs) are involved in the regulation of numerous developmental processes in plants including zygotic embryogenesis, but their biosynthesis and role during somatic embryogenesis (SE) is mostly unknown. In this study we show that during three week- long induction phase, when cells of leaf explants from non-embryogenic genotype (M9) and embryogenic variant (M9-10a) were forming the callus, all the bioactive gibberellins from non-13-hydroxylation (GA4, GA7) and 13-hydroxylation (GA1, GA5, GA3, GA6) pathways were present, but the contents of only a few of them differed between the tested lines. The GA53 and GA19 substrates synthesized by the 13-hydroxylation pathway accumulated specifically in the M9-10a line after the first week of induction; subsequently, among the bioactive gibberellins detected, only the content of GA3 increased and appeared to be connected with acquisition of embryogenic competence. We fully annotated 20 Medicago truncatula orthologous genes coding the enzymes which catalyze all the known reactions of gibberellin biosynthesis. Our results indicate that, within all the genes tested, expression of only three: MtCPS, MtGA3ox1 and MtGA3ox2, was specific to embryogenic explants and reflected the changes observed in GA53, GA19 and GA3 contents. Moreover, by analyzing expression of MtBBM, SE marker gene, we confirmed the inhibitory effect of manipulation in GAs metabolism, applying exogenous GA3, which not only impaired the production of somatic embryos, but also significantly decreased expression of this gene. PMID:28750086

  7. Does gibberellin biosynthesis play a critical role in the growth of Lolium perenne? Evidence from a transcriptional analysis of gibberellin and carbohydrate metabolic genes after defoliation

    PubMed Central

    Liu, Qianhe; Jones, Chris S.; Parsons, Anthony J.; Xue, Hong; Rasmussen, Susanne

    2015-01-01

    Global meat and milk production depends to a large extent on grazed pastures, with Lolium perenne being the major forage grass in temperate regions. Defoliation and subsequent regrowth of leaf blades is a major and essential event with respect to L. perenne growth and productivity. Following defoliation, carbohydrates (mainly fructans and sucrose) have to be mobilized from heterotrophic tissues to provide energy and carbon for regrowth of photosynthetic tissues. This mobilization of reserve carbohydrates requires a substantial change in the expression of genes coding for enzymes involved in carbohydrate metabolism. Here we tested the hypothesis that gibberellins (GA) are at the core of the processes regulating the expression of these genes. Thus, we examined the transcript profiles of genes involved in carbohydrate and GA metabolic pathways across a time course regrowth experiment. Our results show that following defoliation, the immediate reduction of carbohydrate concentrations in growing tissues is associated with a concomitant increase in the expression of genes encoding carbohydrate mobilizing invertases, and was also associated with a strong decrease in the expression of fructan synthesizing fructosyltransferase genes. We also show that the decrease in fructan levels is preceded by increased expression of the GA activating gene GA3-oxidase and decreased expression of the GA inactivating gene GA2-oxidase in sheaths. GA3-oxidase expression was negatively, while GA2-oxidase positively linked to sucrose concentrations. This study provides indicative evidence that gibberellins might play a role in L. perenne regrowth following defoliation and we hypothesize that there is a link between gibberellin regulation and sugar metabolism in L. perenne. PMID:26579182

  8. [Polyphenol content and antioxidant activity of several seeds and nuts].

    PubMed

    Padilla, F C; Rincón, A M; Bou-Rached, L

    2008-09-01

    Foods from plant origin not only provide human diet with certain antioxidant vitamins (C, E and beta-carotene), but also a complex mixture of polyphenols, with antioxidant activity. Numerous studies have been focused on the protective and preventing effect of this antioxidant activity on certain degenerative illnesses such as cardiovascular, cancer, and neurological diseases, cataracts and oxidative stress dysfunctions. The objective of this work was to evaluate total polyphenol content and antioxidant activity of several seeds, nuts, or grains such as Theobroma cacao, Canpsiandra comosa Benth (chiga), Sorghum bicolor, L. Moench, Melicoccus bijugatus (genip). Total polyphenol content was assessed by the Folin-Ciocalteau method and the antioxidant activity by the beta carotene/linoleate, reducing power, and the anti-radical activity methods. Results showed genip pericarp with the lowest polyphenol content (1.40 gGAE/100 g), and cacao beans with the highest (6.66 gGAE/100 g). Reducing power of cacao beans was also the highest and similar to the reducing power of 5.80 g ascorbic acid/100 g, followed by Campsiandra comosa. Moreover, Campsiandra comosa and cacao seeds presented an antioxidant activity comparable to that of the butylhydroxianisol, a synthetic antioxidant. The highest anti-radical activity was shown by Campsiandra comosa with an EC50 of 2.67 g/gDPPH. Total polyphenol content shows a good correlation with the antioxidant activity. Moreover, these seeds might have the same health beneficial effects attributed to other fruits and vegetables.

  9. Effect of photoperiod on gibberellin biosynthetic enzymes in spinach

    SciTech Connect

    Gilmour, S.J.; Bleecker, A.B.; Zeevaart, J.A.D.

    1986-04-01

    The photoperiodic control of stem elongation in spinach, a long day (LD) rosette plant, is mediated by gibberellins (GAs). The early 13-hydroxylated GA biosynthetic pathway from GA/sub 12/ to GA/sub 20/ operates in spinach: GA/sub 12/ ..-->.. GA/sub 53/ ..-->.. GA/sub 44/ ..-->.. GA/sub 19/ ..-->.. GA/sub 20/. Two enzymes of this pathway, those converting GA/sub 53/ to GA/sub 44/ (GA/sub 53/ oxidase) and GA/sub 19/ to GA/sub 20/ (GA/sub 19/ oxidase), are regulated by light. The enzyme converting GA/sub 44/ to GA/sub 19/ (GA/sub 44/ oxidase) is not light-regulated. In the light GA/sub 53/ and GA/sub 18/ oxidase activities are increased, therefore causing the GA biosynthetic pathway to be turned on. This leads to the production of an active GA in LD, which causes an increase in stem elongation. Two the enzymes, GA/sub 44/ and GA/sub 53/ oxidases, can be separated from one another by anion exchange HPLC. Estimates of the molecular weights of these two enzymes based on gel filtration HPLC will be reported.

  10. EarthScope Content Module for IRIS Active Earth Monitor

    NASA Astrophysics Data System (ADS)

    McQuillan, P. J.; Welti, R.; Johnson, J. A.; Shiffman, C. R.; Olds, S. E.

    2012-12-01

    The Active Earth Monitor (AEM) is an interactive computer-based display for university lobbies, museums, visitor centers, schools and libraries. AEM runs in a standard Internet web browser in full screen mode. The display consists of a customizable set of content pages about plate tectonics, earthquakes, volcanoes and tsunamis. Low-cost and simple-to-implement, the Active Earth Monitor provides a way to engage audiences with earth science information without spending resources on a large exhibit. The EarthScope Active Earth Monitor content set highlights the connections between the landscape and the research and monitoring being conducted by EarthScope in partnership with regional monitoring networks. Modules consist of chapters that focus on What is EarthScope?, EarthScope Observatories, and EarthScope Research Results. Content topics are easily explored using a web page button type navigation interface via a touch screen or mouse. A formative evaluation of general public users informed the interface design. Chapters in the modules start with a general overview and proceed to detailed specifics. Each chapter utilizes at least one set of live or near real-time research data (often more than one). This exposes the general public to active ongoing research that is engaging, relevant to the individual user, and explained in easy to understand terms. All live content is updated each time a user accesses the individual page displaying the live data. Leading questions are presented allowing the user to examine the content before accessing the answer via pop-up box. Diagrams and charts of research data have explanatory keys that allow users to self explore all content. Content pages can be created and inserted in the Active Earth Monitor by utilizing the simple HTML/CSS coding.;

  11. A mutant gene that increases gibberellin production in Brassica

    SciTech Connect

    Rood, S.B. ); Williams, P.H. ); Pearce, D.; Pharis, R.P. ); Murofushi, Noboru ); Mander, L.N. )

    1990-07-01

    A single gene mutant (elongated internode (ein/ein)) with accelerated shoot elongation was identified from a rapid cycling line of Brassica rapa. Relative to normal plants, mutant plants had slightly accelerated floral development, greater stem dry weights, and particularly, increased internode and inflorescence elongation. The application of the triazole plant growth retardant, paclobutrazol, inhibited shoot elongation, returning ein to a more normal phenotype. Conversely, exogenous gibberellin A{sub 3} (GA{sub 3}) can convert normal genotypes to a phenotype resembling ein. The content of endogenous GA{sub 1} and GA{sub 3} were estimated by gas chromatography-selected ion monitoring using ({sup 2}H)GA{sub 1} as a quantitative internal standard and at day 14 were 1.5- and 12.1-fold higher per stem, respectively, in ein than in normal plants, although GA concentrations were more similar. The endogenous levels of GA{sub 20} and GA{sub 1}, and the rate of GA{sub 19} metabolism were simultaneously analyzed. Levels of GA{sub 1} and GA{sub 20} were 4.6- and 12.9-fold higher, respectively, and conversions to GA{sub 20} and GA{sub 1} were 8.3 and 1.3 times faster in ein than normal plants. Confirming the enhanced rate of GA{sub 1} biosynthesis in ein, the conversion of ({sup 3}H)GA{sub 20} to ({sup 3}H) GA{sub 1} was also faster in ein than in the normal genotype. Thus, the ein allele results in accelerated GA{sub 1} biosynthesis and an elevated content of endogenous GAs, including the dihydroxylated GAs A{sub 1} and A{sub 3}.

  12. A Mutant Gene That Increases Gibberellin Production in Brassica1

    PubMed Central

    Rood, Stewart B.; Williams, Paul H.; Pearce, David; Murofushi, Noboru; Mander, Lewis N.; Pharis, Richard P.

    1990-01-01

    A single gene mutant (elongated internode [ein/ein]) with accelerated shoot elongation was identified from a rapid cycling line of Brassica rapa. Relative to normal plants, mutant plants had slightly accelerated floral development, greater stem dry weights, and particularly, increased internode and inflorescence elongation. The application of the triazole plant growth retardant, paclobutrazol, inhibited shoot elongation, returning ein to a more normal phenotype. Conversely, exogenous gibberellin A3 (GA3) can convert normal genotypes to a phenotype resembling ein. The content of endogenous GA1 and GA3 were estimated by gas chromatography-selected ion monitoring using [2H]GA1, as a quantitative internal standard and at day 14 were 1.5- and 12.1-fold higher per stem, respectively, in ein than in normal plants, although GA concentrations were more similar. The endogenous levels of GA20 and GA1, and the rate of GA19 metabolism were simultaneously analyzed at day 7 by feeding [2H2]GA19 and measuring metabolites [2H2]GA20 and [2H2]GA1 and endogenous GA20 and GA1, with [2H5]GA20 and [2H5]GA1 as quantitative internal standards. Levels of GA1 and GA20 were 4.6- and 12.9-fold higher, respectively, and conversions to GA20 and GA1 were 8.3 and 1.3 times faster in ein than normal plants. Confirming the enhanced rate of GA1 biosynthesis in ein, the conversion of [3H]GA20 to [3H]GA1 was also faster in ein than in the normal genotype. Thus, the ein allele results in accelerated GA1 biosynthesis and an elevated content of endogenous GAs, including the dihydroxylated GAs A1 and A3. The enhanced GA production probably underlies the accelerated shoot growth and development, and particularly, the increased shoot elongation. Images Figure 1 PMID:16667574

  13. Mechanistic action of gibberellins in legume nodulation.

    PubMed

    Hayashi, Satomi; Gresshoff, Peter M; Ferguson, Brett J

    2014-10-01

    Legume plants are capable of entering into a symbiotic relationship with rhizobia bacteria. This results in the formation of novel organs on their roots, called nodules, in which the bacteria capture atmospheric nitrogen and provide it as ammonium to the host plant. Complex molecular and physiological changes are involved in the formation and establishment of such nodules. Several phytohormones are known to play key roles in this process. Gibberellins (gibberellic acids; GAs), a class of phytohormones known to be involved in a wide range of biological processes (i.e., cell elongation, germination) are reported to be involved in the formation and maturation of legume nodules, highlighted by recent transcriptional analyses of early soybean symbiotic steps. Here, we summarize what is currently known about GAs in legume nodulation and propose a model of GA action during nodule development. Results from a wide range of studies, including GA application, mutant phenotyping, and gene expression studies, indicate that GAs are required at different stages, with an optimum, tightly regulated level being key to achieve successful nodulation. Gibberellic acids appear to be required at two distinct stages of nodulation: (i) early stages of rhizobia infection and nodule primordium establishment; and (ii) later stages of nodule maturation. © 2014 Institute of Botany, Chinese Academy of Sciences.

  14. Thermoperiodic growth control by gibberellin does not involve changes in photosynthetic or respiratory capacities in pea

    PubMed Central

    Stavang, Jon Anders; Pettersen, Rolf Inge; Wendell, Micael; Solhaug, Knut Asbjørn; Junttila, Olavi; Moe, Roar; Olsen, Jorunn E.

    2010-01-01

    Active gibberellin (GA1) is an important mediator of thermoperiodic growth in pea. Plants grown under lower day than night temperature (negative DIF) elongate less and have reduced levels of GA1 compared with plants grown at higher day than night temperature (positive DIF). By comparing the wild type (WT) and the elongated DELLA mutant la crys, this study has examined the effect of impaired GA signalling on thermoperiodic growth, photosynthesis, and respiration in pea. In the WT a negative DIF treatment reduced stem mass ratio and increased both root mass ratio and leaf mass ratio (dry weight of specific tissue related to total plant dry weight). Leaf, root and stem mass ratios of la crys were not affected by DIF. Under negative DIF, specific leaf area (projected leaf area per unit leaf dry mass), biomass, and chlorophyll content of WT and la crys plants were reduced. Young, expanding leaves of plants grown under negative DIF had reduced leaf area-based photosynthetic capacity. However, the highest photosynthetic electron transport rate was found in fully expanded leaves of WT plants grown under negative DIF. Negative DIF increased night respiration and was similar for both genotypes. It is concluded that GA signalling is not a major determinant of leaf area-based photosynthesis or respiration and that reduced dry weight of plants grown under negative DIF is caused by a GA-mediated reduction of photosynthetic stem and leaf tissue, reduced photosynthesis of young, expanding leaves, and reduced growth caused by low temperature in the photoperiod. PMID:20022920

  15. Methylation of Gibberellins by Arabidopsis GAMT1 and GAMT2

    SciTech Connect

    Varbanova,M.; Yamaguchi, S.; Yang, Y.; McKelvey, K.; Hanada, A.; Borochov, R.; Yu, F.; Jikumaru, Y.; Ross, J.; et al

    2007-01-01

    Arabidopsis thaliana GAMT1 and GAMT2 encode enzymes that catalyze formation of the methyl esters of gibberellins (GAs). Ectopic expression of GAMT1 or GAMT2 in Arabidopsis, tobacco (Nicotiana tabacum), and petunia (Petunia hybrida) resulted in plants with GA deficiency and typical GA deficiency phenotypes, such as dwarfism and reduced fertility. GAMT1 and GAMT2 are both expressed mainly in whole siliques (including seeds), with peak transcript levels from the middle until the end of silique development. Within whole siliques, GAMT2 was previously shown to be expressed mostly in developing seeds, and we show here that GAMT1 expression is also localized mostly to seed, suggesting a role in seed development. Siliques of null single GAMT1 and GAMT2 mutants accumulated high levels of various GAs, with particularly high levels of GA1 in the double mutant. Methylated GAs were not detected in wild-type siliques, suggesting that methylation of GAs by GAMT1 and GAMT2 serves to deactivate GAs and initiate their degradation as the seeds mature. Seeds of homozygous GAMT1 and GAMT2 null mutants showed reduced inhibition of germination, compared with the wild type, when placed on plates containing the GA biosynthesis inhibitor ancymidol, with the double mutant showing the least inhibition. These results suggest that the mature mutant seeds contained higher levels of active GAs than wild-type seeds.

  16. Chrysosporium pseudomerdarium produces gibberellins and promotes plant growth.

    PubMed

    Hamayun, Muhammad; Khan, Sumera Afzal; Iqbal, Ilyas; Na, Chae-In; Khan, Abdul Latif; Hwang, Young-Hyun; Lee, Byung-Hyun; Lee, In-Jung

    2009-08-01

    We isolated 10 endophytic fungi from the roots of drought stressed soybean cultivar Hwangkeumkong and bioassayed on waito-c rice and soybean seedlings, in order to identify plant growth-promoting fungi. The fungal isolate D-2-1 provided the best result for plant height and biomass promotion as compared to wild type Gibberella fujikuroi. The D-2-1 culture filtrate (CF) was analyzed for the presence of gibberellins (GAs) and it was observed that all physiologically active GAs, especially gibberellic acid, were present in higher amounts (GA1, 0.24 ng/ml; GA3, 8.99 ng/ml; GA4, 2.58 ng/ml and GA7, 1.39 ng/ml) in conjunction with physiologically inactive GA5, GA9, GA15, GA19, and GA24. The fungal isolate D-2-1 was identified as a new strain of Chrysosporium pseudomerdarium through phylogenetic analysis of 18S rDNA sequence. Plant growth promotion and GAs production capacity of genus Chrysosporium have been reported for the first time in this study.

  17. Antihemolytic activity and mineral contents of Juglans regia L. flowers.

    PubMed

    Ebrahimzadeh, M A; Nabavi, S F; Nabavi, S M

    2013-07-01

    Juglans (J.) regia L. is known to possess many biological properties. In this study, antihemolytic activity of methanol extract of Juglans regia L. flower were investigated. Antihemolytic activities of Juglans regia L. flowers were evaluated by various in vitro assays. In addition, scavenging of hydrogen peroxide and mineral contents of flowers were determined using atomic absorption spectroscopy. Extract showed good antihemolytic activity against H2O2 and CuOOH induced hemolysis in comparison with control. Extract was capable of scavenging H2O2 in a concentration dependent manner. IC50 for H2O2 scavenging activity was 311±12.8 µg ml-1. The amount of eight elements was determined and was in the order: Mn > Cu > Fe > Zn. Our study indicate that J. regia flower has remarkable antihemolytic activity, which maybe result of its high phenol and flavonoid contents, especially quercetin.

  18. Influence of gibberellin and daminozide on the expression of terpene synthases and on monoterpenes in common sage (Salvia officinalis).

    PubMed

    Schmiderer, Corinna; Grausgruber-Gröger, Sabine; Grassi, Paolo; Steinborn, Ralf; Novak, Johannes

    2010-07-01

    Common sage (Salvia officinalis L., Lamiaceae) is one of the most important medicinal and aromatic plants, with antioxidant, antimicrobial, spasmolytic, astringent, antihidrotic and specific sensorial properties. The essential oil of the plant, composed mainly of the monoterpenes 1,8-cineole, alpha-thujone, beta-thujone and camphor, is responsible for some of these effects. Gibberellins regulate diverse physiological processes in plants, such as seed germination, shoot elongation and cell division. In this study, we analyzed the effect of exogenously applied plant growth regulators, namely gibberellic acid (GA(3)) and daminozide, on leaf morphology and essential oil formation of two leaf stages during the period of leaf expansion. Essential oil content increased with increasing levels of gibberellins and decreased when gibberellin biosynthesis was blocked with daminozide. With increasing levels of gibberellins, 1,8-cineole and camphor contents increased. Daminozide blocked the accumulation of alpha- and beta-thujone. GA(3) at the highest level applied also led to a significant decrease of alpha- and beta-thujone. Monoterpene synthases are a class of enzymes responsible for the first step in monoterpene biosynthesis, competing for the same substrate geranylpyrophosphate. The levels of gene expression of the three most important monoterpene synthases in sage were investigated, 1,8-cineole synthase leading directly to 1,8-cineole, (+)-sabinene synthase responsible for the first step in the formation of alpha- and beta-thujone, and (+)-bornyl diphosphate synthase, the first step in camphor biosynthesis. The foliar application of GA(3) increased, while daminozide significantly decreased gene expression of the monoterpene synthases. The amounts of two of the end products, 1,8-cineole and camphor, were directly correlated with the levels of gene expression of the respective monoterpene synthases, indicating transcriptional control, while the formation of alpha- and beta

  19. Gibberellin metabolism in Vitis vinifera L. during bloom and fruit-set: functional characterization and evolution of grapevine gibberellin oxidases

    PubMed Central

    Giacomelli, Lisa

    2013-01-01

    Gibberellins (GAs) are involved in the regulation of flowering and fruit-set in grapes (Vitis vinifera L.), but the molecular mechanisms behind this process are mostly unknown. In this work, the family of grapevine GA oxidases involved in the biosynthesis and deactivation of GAs was characterized. Six putative GA 20-oxidase (GA20ox), three GA 3-oxidase (GA3ox), and eight GA 2-oxidase (GA2ox) proteins, the latter further divided into five C19-GA 2ox and three C20-GA2ox proteins, were identified. Phylogenetic analyses suggest a common origin of the GA3ox and C19-GA2ox groups and challenge previous evolutionary models. In vitro analysis revealed that all GA3ox and GA20ox enzymes prefer substrates of the non-13-hydroxylation pathway. In addition, ectopic expression of GA2ox genes in Arabidopsis thaliana confirmed the activity of their encoded proteins in vivo. The results show that bioactive GA1 accumulates in opening grapevine flowers, whereas at later developmental stages only GA4 is detected in the setting fruit. By studying the expression pattern of the grapevine GA oxidase genes in different organs, and at different stages of flowering and fruit-set, it is proposed that the pool of bioactive GAs is controlled by a fine regulation of the abundance and localization of GA oxidase transcripts. PMID:24006417

  20. Gibberellin metabolism in Vitis vinifera L. during bloom and fruit-set: functional characterization and evolution of grapevine gibberellin oxidases.

    PubMed

    Giacomelli, Lisa; Rota-Stabelli, Omar; Masuero, Domenico; Acheampong, Atiako Kwame; Moretto, Marco; Caputi, Lorenzo; Vrhovsek, Urska; Moser, Claudio

    2013-11-01

    Gibberellins (GAs) are involved in the regulation of flowering and fruit-set in grapes (Vitis vinifera L.), but the molecular mechanisms behind this process are mostly unknown. In this work, the family of grapevine GA oxidases involved in the biosynthesis and deactivation of GAs was characterized. Six putative GA 20-oxidase (GA20ox), three GA 3-oxidase (GA3ox), and eight GA 2-oxidase (GA2ox) proteins, the latter further divided into five C19-GA 2ox and three C20-GA2ox proteins, were identified. Phylogenetic analyses suggest a common origin of the GA3ox and C19-GA2ox groups and challenge previous evolutionary models. In vitro analysis revealed that all GA3ox and GA20ox enzymes prefer substrates of the non-13-hydroxylation pathway. In addition, ectopic expression of GA2ox genes in Arabidopsis thaliana confirmed the activity of their encoded proteins in vivo. The results show that bioactive GA1 accumulates in opening grapevine flowers, whereas at later developmental stages only GA4 is detected in the setting fruit. By studying the expression pattern of the grapevine GA oxidase genes in different organs, and at different stages of flowering and fruit-set, it is proposed that the pool of bioactive GAs is controlled by a fine regulation of the abundance and localization of GA oxidase transcripts.

  1. Content Analysis of a Computer-Based Faculty Activity Repository

    ERIC Educational Resources Information Center

    Baker-Eveleth, Lori; Stone, Robert W.

    2013-01-01

    The research presents an analysis of faculty opinions regarding the introduction of a new computer-based faculty activity repository (FAR) in a university setting. The qualitative study employs content analysis to better understand the phenomenon underlying these faculty opinions and to augment the findings from a quantitative study. A web-based…

  2. Improving Preservice Chemistry Teachers' Content Knowledge through Intervention Activities

    ERIC Educational Resources Information Center

    Wheeldon, Ruth

    2017-01-01

    The effect of intervention activities on the chemistry content knowledge of 92 preservice chemistry teachers (PSCT) was examined via a pre and post true/false with confidence level test focusing on ionisation energy values and the use of a common alternative conception (AC). Data were collected from three cohorts of PSCT each engaged in a one year…

  3. The effect of clothing care activities on textile formaldehyde content.

    PubMed

    Novick, Rachel M; Nelson, Mindy L; McKinley, Meg A; Anderson, Grace L; Keenan, James J

    2013-01-01

    Textiles are commonly treated with formaldehyde-based residues that may potentially induce allergic contact dermatitis in sensitive individuals. This study examined the initial formaldehyde content in clothing and resulting changes due to care activities. Twenty clothing articles were examined and 17 of them did not have detectable levels of formaldehyde. One shirt contained a formaldehyde concentration of 3172 ppm, and two pairs of pants had formaldehyde concentrations of 1391 ppm and 86 ppm. The two highest results represent formaldehyde levels that are up to 40-fold greater than international textile regulations. The two items with the greatest formaldehyde content were washed and dried in a manner similar to that used by consumers, including hand and machine washing in hot or cold water followed by air or machine drying. The washing and drying procedures reduced formaldehyde levels to between 26 and 72% of untreated controls. Differences in the temperature or type of washing and drying did not result in a clear trend in the subsequent formaldehyde content. In addition, samples were hot ironed, which did not affect the formaldehyde content as significantly. Understanding the formaldehyde content in clothing and its potential reduction through care activities may be useful for manufacturers and formaldehyde-sensitive individuals.

  4. Gibberellins and Heterosis in Maize 1

    PubMed Central

    Rood, Stewart B.; Blake, Terence J.; Pharis, Richard P.

    1983-01-01

    Two maize inbreds, CM7 and CM49, and CM7 × CM49, their F1 hybrid (which displayed significant heterosis), were examined with regard to response to exogenous gibberellin A3 (GA3), and in their ability to metabolize GA20, a native GA of maize. The leaf sheath elongation response to GA3 was far greater for the imbreds than for their hybrid. The inbreds also displayed significant elongation of the leaf blades in response to GA3, whereas the hybrid was unaffected. Promotion of cell division in the leaf sheath of CM7 and the hybrid was effected by GA3, but no promotion of cell elongation was observed in CM49, even though significant leaf sheath elongation occurred. Shoot dry weight of both inbreds was significantly increased by GA3, but response by the hybrid in this parameter was slight and variable. Root dry weight of CM7 was significantly increased by GA3, but was unchanged in CM49 and the hybrid. Thus, inbred shoot dry weight increases effected by GA3 were not at the expense of the root system. Rapid metabolism of [2,3-3H]GA20 occurred in all genotypes, although genotypic differences were observed. The hybrid had the highest rates of metabolism to GA glucosyl conjugate-like substances. Oxidative metabolism was also fastest in the hybrid, followed by CM7, and slowest in CM49, the slowest-growing inbred. Thus, rate of GA20 metabolism is under genetic control in normal (i.e. not dwarfed) maize genotypes. These results, taken together with previous reports that the hybrid has significantly enhanced levels of endogenous GA-like substances, suggest that GA play a role in the expression of heterosis in maize. Images Fig. 2 PMID:16662881

  5. Gibberellin Biosynthesis in Developing Pumpkin Seedlings12

    PubMed Central

    Lange, Theo; Kappler, Jeannette; Fischer, Andreas; Frisse, Andrea; Padeffke, Tania; Schmidtke, Sabine; Lange, Maria João Pimenta

    2005-01-01

    A gibberellin (GA) biosynthetic pathway was discovered operating in root tips of 7-d-old pumpkin (Cucurbita maxima) seedlings. Stepwise analysis of GA metabolism in cell-free systems revealed the conversion of GA12-aldehyde to bioactive GA4 and inactive GA34. Highest levels of endogenous GA4 and GA34 were found in hypocotyls and root tips of 3-d-old seedlings. cDNA molecules encoding two GA oxidases, CmGA20ox3 and CmGA3ox3, were isolated from root tips of 7-d-old LAB150978-treated seedlings. Recombinant CmGA20ox3 fusion protein converted GA12 to GA9, GA24 to GA9, GA14 to GA4, and, less efficiently, GA53 to GA20, and recombinant CmGA3ox3 protein oxidized GA9 to GA4. Transcript profiles were determined for four GA oxidase genes from pumpkin revealing relatively high transcript levels for CmGA7ox in shoot tips and cotyledons, for CmGA20ox3 in shoot tips and hypocotyls, and for CmGA3ox3 in hypocotyls and roots of 3-d-old seedlings. Transcripts of CmGA2ox1 were mainly found in roots of 7-d-old seedlings. In roots of 7-d-old seedlings, transcripts of CmGA7ox, CmGA20ox3, and CmGA3ox3 were localized in the cap and the rhizodermis by in situ hybridization. We conclude that hypocotyls and root tips are important sites of GA biosynthesis in the developing pumpkin seedling. PMID:16126862

  6. Inhibition of Gibberellin Production in the Fungi Gibberella fujikuroi and Sphaceloma manihoticola by Plant Growth Retardants

    PubMed Central

    Rademacher, Wilhelm

    1992-01-01

    The effect of different types of plant growth retardants on fungal gibberellin (GA) formation has been studied in cultures of Gibberella fujikuroi and Sphaceloma manihoticola. Quaternary ammonium compounds (chlormequat chloride, mepiquat chloride, Amo-1618), triazoles (uniconazole and several experimental compounds), and the norbornanodiazetine tetcyclacis inhibited GA biosynthesis in both fungal species. Concentrations between 2 × 10−4 and 10−9m were required for a 50% inhibition of the production of gibberellin A3 in Gibberella fujikuroi and of giberellin A4 in Sphaceloma manihoticola. The formation of other prominent GAs was affected at a similar degree of intensity. Tetcyclacis was the most active compound in both fungi. Compared to the growth retardants mentioned above, the biological activity of chlorphonium chloride was low. The acylcyclohexanediones prohexadione and LAB 198 999 had virtually no activity. Most likely, this lack of activity is due to a rapid metabolism of the compounds in the cultures. For the triazole-type compounds and tetcyclacis, a relatively distinct correlation exists in their ability to inhibit GA formation in fungal cultures, to block ent-kaurene oxygenase in a cell-free system, and to reduce shoot growth of rice seedlings. Due to differences in their metabolic fate and species specificities, such conclusions cannot be made for the other compounds. PMID:16653038

  7. Gibberellin-induced formation of tension wood in angiosperm trees.

    PubMed

    Funada, Ryo; Miura, Tatsuhiko; Shimizu, Yousuke; Kinase, Takanori; Nakaba, Satoshi; Kubo, Takafumi; Sano, Yuzou

    2008-05-01

    After gibberellin had been applied to the vertical stems of four species of angiosperm trees for approximately 2 months, we observed eccentric radial growth that was due to the enhanced growth rings on the sides of stems to which gibberellin had been applied. Moreover, the application of gibberellin resulted in the formation of wood fibers in which the thickness of inner layers of cell walls was enhanced. These thickened inner layers of cell walls were unlignified or only slightly lignified. In addition, cellulose microfibrils on the innermost surface of these thickened inner layers of cell walls were oriented parallel or nearly parallel to the longitudinal axis of the fibers. Such thickened inner layers of cell walls had features similar to those of gelatinous layers in the wood fibers of tension wood, which are referred to as gelatinous fibers. Our anatomical and histochemical investigations indicate that the application of gibberellin can induce the formation of tension wood on vertical stems of angiosperm trees in the absence of gravitational stimulus.

  8. Evolutionary conservation of plant gibberellin signalling pathway components

    PubMed Central

    Vandenbussche, Filip; Fierro, Ana C; Wiedemann, Gertrud; Reski, Ralf; Van Der Straeten, Dominique

    2007-01-01

    Background: Gibberellins (GA) are plant hormones that can regulate germination, elongation growth, and sex determination. They ubiquitously occur in seed plants. The discovery of gibberellin receptors, together with advances in understanding the function of key components of GA signalling in Arabidopsis and rice, reveal a fairly short GA signal transduction route. The pathway essentially consists of GID1 gibberellin receptors that interact with F-box proteins, which in turn regulate degradation of downstream DELLA proteins, suppressors of GA-controlled responses. Results: Arabidopsis sequences of the gibberellin signalling compounds were used to screen databases from a variety of plants, including protists, for homologues, providing indications for the degree of conservation of the pathway. The pathway as such appears completely absent in protists, the moss Physcomitrella patens shares only a limited homology with the Arabidopsis proteins, thus lacking essential characteristics of the classical GA signalling pathway, while the lycophyte Selaginella moellendorffii contains a possible ortholog for each component. The occurrence of classical GA responses can as yet not be linked with the presence of homologues of the signalling pathway. Alignments and display in neighbour joining trees of the GA signalling components confirm the close relationship of gymnosperms, monocotyledonous and dicotyledonous plants, as suggested from previous studies. Conclusion: Homologues of the GA-signalling pathway were mainly found in vascular plants. The GA signalling system may have its evolutionary molecular onset in Physcomitrella patens, where GAs at higher concentrations affect gravitropism and elongation growth. PMID:18047669

  9. Phenolic content, antibacterial and antioxidant activities of Erica herbacea L.

    PubMed

    Vucić, Dragana M; Petković, Miroslav R; Rodić-Grabovac, Branka B; Stefanović, Olgica D; Vasić, Sava M; Comić, Ljiljana R

    2013-01-01

    Antibacterial and antioxidant activity, total phenolic and flavonoid concentrations of aqueous, ethanol and ethyl acetate extracts from the leaves and flowers of Erica herbacea L. were studied. In vitro antibacterial activity of the extracts was determined by macrodilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) have been determined. Testing was performed on 30 clinical isolates, including different strains of Escherichia coli, Enterococcus faecalis and Proteus vulgaris. The values for MIC were in the range from 2.5 mg/mL to 40 mg/mL. The most sensitive bacterial strains were Proteus vulgaris strains. The aqueous extract from E. herbacea was found the most active. The total phenolic content was determined using Folin-Ciocalteu reagent and ranged between 14.98 and 119.88 mg GA/g. The concentration of flavonoids in extracts was determined using spectrophotometric method with aluminium chloride and obtained results varied from 16.19 to 26.90 mg RU/g. Antioxidant activity was monitored spectrophotometrically using DPPH reagent. The highest capacity to neutralize DPPH radicals was found in the aqueous extract from E. herbacea. The results of the total phenolic content determination of the examined extracts indicate that E. herbacea extracts are a rich source of phenolic compounds and also possess a significant antioxidant activity and moderate antibacterial activity.

  10. Fruit growth in Arabidopsis occurs via DELLA-dependent and DELLA-independent gibberellin responses.

    PubMed

    Fuentes, Sara; Ljung, Karin; Sorefan, Karim; Alvey, Elizabeth; Harberd, Nicholas P; Østergaard, Lars

    2012-10-01

    Fruit growth and development depend on highly coordinated hormonal activities. The phytohormone gibberellin (GA) promotes growth by inducing degradation of the growth-repressing DELLA proteins; however, the extent to which DELLA proteins contribute to GA-mediated gynoecium and fruit development remains to be clarified. Here, we provide an in-depth characterization of the role of DELLA proteins in Arabidopsis thaliana fruit growth. We show that DELLA proteins are key regulators of reproductive organ size and important for ensuring optimal fertilization. We demonstrate that the seedless fruit growth (parthenocarpy) observed in della mutants can be directly attributed to the constitutive activation of GA signaling. It has been known for >75 years that another hormone, auxin, can induce formation of seedless fruits. Using mutants with complete lack of DELLA activity, we show here that auxin-induced parthenocarpy occurs entirely through GA signaling in Arabidopsis. Finally, we uncover the existence of a DELLA-independent GA response that promotes fruit growth. This response requires GIBBERELLIN-INSENSITIVE DWARF1-mediated GA perception and a functional 26S proteasome and involves the basic helix-loop-helix protein SPATULA as a key component. Taken together, our results describe additional complexities in GA signaling during fruit development, which may be particularly important to optimize the conditions for successful reproduction.

  11. Expression Studies of Gibberellin Oxidases in Developing Pumpkin Seeds1

    PubMed Central

    Frisse, Andrea; Pimenta, Maria João; Lange, Theo

    2003-01-01

    Two cDNA clones, 3-ox and 2-ox, have been isolated from developing pumpkin (Cucurbita maxima) embryos that show significant amino acid homology to gibberellin (GA) 3-oxidases and 2-oxidases, respectively. Recombinant fusion protein of clone 3-ox converted GA12-aldehyde, GA12, GA15, GA24, GA25, and GA9 to GA14-aldehyde, GA14, GA37, GA36, GA13, and GA4, respectively. Recombinant 2-ox protein oxidized GA9, GA4, and GA1 to GA51, GA34, and GA8, respectively. Previously cloned GA 7-oxidase revealed additional 3β-hydroxylation activity of GA12. Transcripts of this gene were identified in endosperm and embryo of the developing seed by quantitative reverse transcriptase-polymerase chain reaction and localized in protoderm, root apical meristem, and quiescent center by in situ hybridization. mRNA of the previously cloned GA 20-oxidase from pumpkin seeds was localized in endosperm and in tissues of protoderm, ground meristem, and cotyledons of the embryo. However, transcripts of the recently cloned GA 20-oxidase from pumpkin seedlings were found all over the embryo, and in tissues of the inner seed coat at the micropylar end. Previously cloned GA 2β,3β-hydroxylase mRNA molecules were specifically identified in endosperm tissue. Finally, mRNA molecules of the 3-ox and 2-ox genes were found in the embryo only. 3-ox transcripts were localized in tissues of cotyledons, protoderm, and inner cell layers of the root apical meristem, and 2-ox transcripts were found in all tissues of the embryo except the root tips. These results indicate tissue-specific GA-biosynthetic pathways operating within the developing seed. PMID:12644672

  12. Expression studies of gibberellin oxidases in developing pumpkin seeds.

    PubMed

    Frisse, Andrea; Pimenta, Maria João; Lange, Theo

    2003-03-01

    Two cDNA clones, 3-ox and 2-ox, have been isolated from developing pumpkin (Cucurbita maxima) embryos that show significant amino acid homology to gibberellin (GA) 3-oxidases and 2-oxidases, respectively. Recombinant fusion protein of clone 3-ox converted GA(12)-aldehyde, GA(12), GA(15), GA(24), GA(25), and GA(9) to GA(14)-aldehyde, GA(14), GA(37), GA(36), GA(13), and GA(4), respectively. Recombinant 2-ox protein oxidized GA(9), GA(4), and GA(1) to GA(51), GA(34), and GA(8), respectively. Previously cloned GA 7-oxidase revealed additional 3beta-hydroxylation activity of GA(12). Transcripts of this gene were identified in endosperm and embryo of the developing seed by quantitative reverse transcriptase-polymerase chain reaction and localized in protoderm, root apical meristem, and quiescent center by in situ hybridization. mRNA of the previously cloned GA 20-oxidase from pumpkin seeds was localized in endosperm and in tissues of protoderm, ground meristem, and cotyledons of the embryo. However, transcripts of the recently cloned GA 20-oxidase from pumpkin seedlings were found all over the embryo, and in tissues of the inner seed coat at the micropylar end. Previously cloned GA 2beta,3beta-hydroxylase mRNA molecules were specifically identified in endosperm tissue. Finally, mRNA molecules of the 3-ox and 2-ox genes were found in the embryo only. 3-ox transcripts were localized in tissues of cotyledons, protoderm, and inner cell layers of the root apical meristem, and 2-ox transcripts were found in all tissues of the embryo except the root tips. These results indicate tissue-specific GA-biosynthetic pathways operating within the developing seed.

  13. Arabidopsis RGL1 Encodes a Negative Regulator of Gibberellin Responses

    PubMed Central

    Wen, Chi-Kuang; Chang, Caren

    2002-01-01

    In Arabidopsis, the DELLA subfamily of GRAS regulatory genes consists of GAI, RGA, RGA-LIKE1 (RGL1), RGL2, and RGL3. GAI and RGA are known to be negative regulators of gibberellin (GA) responses. We found that RGL1 is a similar repressor of GA responses, as revealed by RGL1 gain-of-function and loss-of-function phenotypes. Repression of GA responses in Arabidopsis was conferred by a dominant 35S-rgl1 transgene carrying a DELLA domain deletion analogous to the GA-insensitive gai-1 mutation. As in GA-deficient Arabidopsis, the transgenic plants were dark green dwarfs with underdeveloped trichomes and flowers. Expression levels of GA4, a feedback-regulated GA biosynthetic gene, were increased correspondingly. Conversely, a loss-of-function rgl1 line had reduced GA4 expression and exhibited GA-independent activation of seed germination, leaf expansion, flowering, stem elongation, and floral development, as detected by resistance to the GA biosynthesis inhibitor paclobutrazol. RGL1 plays a greater role in seed germination than do GAI and RGA. The expression profile of RGL1 differed from those of the four other DELLA homologs. RGL1 message levels were predominant in flowers, with transcripts detected in developing ovules and anthers. As with RGA, green fluorescent protein (GFP)–tagged RGL1 protein was localized to the nucleus, but unlike GFP-RGA, there was no degradation after GA treatment. These findings indicate that RGL1 is a partially redundant, but distinct, negative regulator of GA responses and suggest that all DELLA subfamily members might possess separate as well as overlapping roles in GA signaling. PMID:11826301

  14. Gibberellic Acid-Promoted Lignification and Phenylalanine Ammonia-lyase Activity in a Dwarf Pea (Pisum sativum) 1

    PubMed Central

    Cheng, Christina K.-C.; Marsh, H. V.

    1968-01-01

    The effects of gibberellic acid on lignification in seedlings of a dwarf and a tall cultivar of pea (Pisum sativum) grown under red or white light or in the darkness, were studied. Gibberellic acid (10−6-10−4 m) promoted stem elongation in both light and dark and increased the percentage of lignin in the stems of the light-grown dwarf pea. The gibberellin had no effect on the lignin content of the tall pea although high concentrations (10−4 m) promoted growth of the tall plants. Time course studies indicated that the enhanced lignification in the gibberellin-treated dwarf plants occurred only after a lag period of several days. It was concluded that gibberellic acid-enhanced ligmification had no direct relation to gibberellic acid-promoted growth. The activity of phenylalanine ammonia-lyase (E.C. 4.3.1.5) was higher in gibberellin-treated dwarf plants grown under white or red light than in untreated dwarf plants. Gibberellic acid had no detectable effect on the activity of this enzyme when the plants were grown in darkness, just as it had no effect on lignification under dark conditions. The data suggest that in gibberellin-deficient peas the activity of phenylalanine ammonia-lyase is one of the limiting factors in lignification. PMID:16656968

  15. Antioxidant Content, Antioxidant Activity, and Antibacterial Activity of Five Plants from the Commelinaceae Family

    PubMed Central

    Tan, Joash Ban Lee; Yap, Wei Jin; Tan, Shen Yeng; Lim, Yau Yan; Lee, Sui Mae

    2014-01-01

    Commelinaceae is a family of herbaceous flowering plants with many species used in ethnobotany, particularly in South America. However, thus far reports of their bioactivity are few and far between. The primary aim of this study was to quantify the antioxidant and antibacterial activity of five Commelinaceae methanolic leaf extracts. The antioxidant content was evaluated by the total phenolic content (TPC), total tannin content (TTC), and total flavonoid content (TFC) assays. The antioxidant activities measured were DPPH free radical scavenging (FRS), ferric reducing power (FRP), and ferrous ion chelating (FIC); of the five plants, the methanolic leaf extract of Tradescantia zebrina showed the highest antioxidant content and activity, and exhibited antibacterial activity against six species of Gram-positive and two species of Gram-negative bacteria in a range of 5–10 mg/mL based on the broth microdilution method. PMID:26785239

  16. Substituted Phthalimide AC94377 Is a Selective Agonist of the Gibberellin Receptor GID11[OPEN

    PubMed Central

    Otani, Masato; Shimotakahara, Hiroaki; Yoon, Jung-Min; Park, Seung-Hyun; Miyaji, Tomoko; Nakano, Takeshi; Nakamura, Hidemitsu; Nakajima, Masatoshi

    2017-01-01

    Gibberellin (GA) is a major plant hormone that regulates plant growth and development and is widely used as a plant growth regulator in agricultural production. There is an increasing demand for function-limited GA mimics due to the limitations on the agronomical application of GA to crops, including GA’s high cost of producing and its leading to the crops’ lodging. AC94377, a substituted phthalimide, is a chemical that mimics the growth-regulating activity of GAs in various plants, despite its structural difference. Although AC94377 is widely studied in many weeds and crops, its mode of action as a GA mimic is largely unknown. In this study, we confirmed that AC94377 displays GA-like activities in Arabidopsis (Arabidopsis thaliana) and demonstrated that AC94377 binds to the Arabidopsis GIBBERELLIN INSENSITIVE DWARF1 (GID1) receptor (AtGID1), forms the AtGID1-AC94377-DELLA complex, and induces the degradation of DELLA protein. Our results also indicated that AC94377 is selective for a specific subtype among three AtGID1s and that the selectivity of AC94377 is attributable to a single residue at the entrance to the hydrophobic pocket of GID1. We conclude that AC94377 is a GID1 agonist with selectivity for a specific subtype of GID1, which could be further developed and used as a function-limited regulator of plant growth in both basic study and agriculture. PMID:27899534

  17. Cloning and characterization of a gibberellin-induced RNase expressed in barley aleurone cells

    SciTech Connect

    Rogers, S.W.; Rogers, J.C. . Inst. of Biological Chemistry)

    1999-04-01

    The authors cloned a cDNA for a gibberellin-induced ribonuclease (RNase) expressed in barley (Hordeum vulgare) aleurone and the gene for a second barley RNase expressed in leaf tissue. The protein encoded by the cDNA is unique among RNases described to date in that it contains a novel 23-amino acid insert between the C2 and C3 conserved sequences. Expression of the recombinant protein in tobacco (Ncotiana tabacum) suspension-cultured protoplasts gave an active RNase of the expected size, confirming the enzymatic activity of the protein. Analyses of hormone regulation of re-expression of mRNA for the aleurone RNase revealed that, like the pattern for [alpha]-amylase, mRNA levels increased in the presence of gibberellic acid, and its antagonist abscisic acid prevented this effect. Quantitative studies at early times demonstrated that cycloheximide treatment of aleurone layers increased mRNA levels 4-fold, whereas a combination of gibberellin plus cycloheximide treatment was required to increase [alpha]-amylase mRNA levels to the same extent. These results are consistent with loss of repression as an initial effect of gibberellic acid on transcription of those genes, although the regulatory pathways for the two genes may differ.

  18. Flavonoid content and antioxidant activity of vegetables from Indonesia

    PubMed Central

    Andarwulan, Nuri; Batari, Ratna; Sandrasari, Diny Agustini; Bolling, Bradley; Wijaya, Hanny

    2017-01-01

    Extracts from 11 vegetables of Indonesian origin were screened for flavonoid content, total phenolics, and antioxidant activity. The flavonols myricetin, quercetin, and kaempferol and flavones luteolin and apigenin were quantified by HPLC. Flavonoid content in mg/100 g fresh weight (fw) was apparently initially reported for Cosmos caudatus H.B.K. (52.19), Polyscias pinnata (52.19), Pluchea indica Less. (6.39), Nothopanax scutellarius (Burm.f.) Merr (5.43), Talinum triangulare (Jacq.) Willd. (3.93), Pilea melastomoides (Poir.) Bl. (2.27), and Etlingera elatior (Jack) R.M.Sm (1.18). The flavonoid content of the vegetables studied were mainly quercetin and kaempferol and ranged from 0.3 to 143 mg/100 g fw, with the highest level found in Sauropus androgynus (L) Merr. C. caudatus H.B.K. had the greatest total phenols among the vegetables analysed, with 1.52 mg GAE/100 g fw. P. indica Less. and C. caudatus H.B.K. had the highest antioxidant activity as measured by ferric cyanide reducing power, DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) scavenging, and inhibition of linoleic acid oxidation. Therefore, S. androgynus (L) Merr, C. caudatus H.B.K., and P. pinnata were identified as potentially rich sources of dietary flavonoids and antioxidants. PMID:28814820

  19. Arbutin content and antioxidant activity of some Ericaceae species.

    PubMed

    Pavlović, R D; Lakusić, B; Doslov-Kokorus, Z; Kovacević, N

    2009-10-01

    Quantitative analyses and investigation of antioxidant activity of herb and dry ethanolic extracts of five species from Ericaceae family (Arbutus unedo L., Bruckentalia spiculifolia Rchb., Calluna vulgaris Salisb., Erica arborea L. and Erica carnea L.) were performed. Total polyphenols, tannins and flavonoids were determined spectrophotometrically and arbutin content was measured both spectrophotometrically and by HPLC coupled with DAD detection. Antioxidative properites of the ethanolic extracts were tested by means of FRAP (total antioxidant capacity), lipid peroxidation and DPPH free radical scavenging activity. A significant amount of arbutin was detected only in Arbutus unedo. All samples investigated showed excellent antioxidant activity. The best inhibition of lipid peroxidation has been shown by Bruckentalia spiculifolia herb extract (62.5 microg/ml; more than 95%), which contained the highest amount of flavonoids (11.79%). The highest scavenging activity was obtained with leave extract of Arbutus unedo (IC50 = 7.14 microg/ml). The leaves of A. unedo contained a small amount of flavonoids but high content of non-tannins polyphenols.

  20. Gibberellin 3-oxidase Gene Expression Patterns Influence Gibberellin Biosynthesis, Growth, and Development in Pea1[W][OPEN

    PubMed Central

    Reinecke, Dennis M.; Wickramarathna, Aruna D.; Ozga, Jocelyn A.; Kurepin, Leonid V.; Jin, Alena L.; Good, Allen G.; Pharis, Richard P.

    2013-01-01

    Gibberellins (GAs) are key modulators of plant growth and development. PsGA3ox1 (LE) encodes a GA 3β-hydroxylase that catalyzes the conversion of GA20 to biologically active GA1. To further clarify the role of GA3ox expression during pea (Pisum sativum) plant growth and development, we generated transgenic pea lines (in a lele background) with cauliflower mosaic virus-35S-driven expression of PsGA3ox1 (LE). PsGA3ox1 transgene expression led to higher GA1 concentrations in a tissue-specific and development-specific manner, altering GA biosynthesis and catabolism gene expression and plant phenotype. PsGA3ox1 transgenic plants had longer internodes, tendrils, and fruits, larger stipules, and displayed delayed flowering, increased apical meristem life, and altered vascular development relative to the null controls. Transgenic PsGA3ox1 overexpression lines were then compared with lines where endogenous PsGA3ox1 (LE) was introduced, by a series of backcrosses, into the same genetic background (BC LEle). Most notably, the BC LEle plants had substantially longer internodes containing much greater GA1 levels than the transgenic PsGA3ox1 plants. Induction of expression of the GA deactivation gene PsGA2ox1 appears to make an important contribution to limiting the increase of internode GA1 to modest levels for the transgenic lines. In contrast, PsGA3ox1 (LE) expression driven by its endogenous promoter was coordinated within the internode tissue to avoid feed-forward regulation of PsGA2ox1, resulting in much greater GA1 accumulation. These studies further our fundamental understanding of the regulation of GA biosynthesis and catabolism at the tissue and organ level and demonstrate that the timing/localization of GA3ox expression within an organ affects both GA homeostasis and GA1 levels, and thereby growth. PMID:23979969

  1. Roles of gibberellins and abscisic acid in dormancy and germination of red bayberry (Myrica rubra) seeds.

    PubMed

    Chen, Shun-Ying; Kuo, Shing-Rong; Chien, Ching-Te

    2008-09-01

    Intact seeds from freshly harvested fruits of Myrica rubra (Sieb et Zucc.) were dormant and required 8 weeks of warm stratification followed by 12 weeks of cold stratification for germination. Exogenous application of gibberellic acid (GA(3)) to intact fresh seeds was effective in breaking dormancy, with > 70% of seeds germinating when treated with 5.2 mM GA(3) and incubated at a day/night temperature of 30/20 degrees C for 20 weeks. Removing the hard endocarp or endocarp plus seed coat of fresh seeds promoted germination, and addition of GA(3) to the embryo accelerated germination. The gibberellins GA(1) and GA(4) were more effective than GA(3) in promoting germination of seeds with the endocarp removed. Endogenous contents of GA(1), GA(3), GA(4), GA(7) and GA(20) were quantified by gas chromatography-mass spectrometry-selected ion monitoring in the endocarps, seed coats and embryos of fresh seeds treated with 5.2 mM GA(3). The content of GA(3) decreased in the endocarp during incubation, whereas GA(1) contents increased in the endocarp and seed coat. A high GA(1) content was detected in the endocarps and embryos of newly germinated seeds. We speculate that GA(3) was converted to GA(1) during incubation and that GA(1) is involved in seed germination. Endogenous abscisic acid (ABA) contents were measured in fresh seeds and in warm and cold stratified seeds. The ABA content in fresh seeds was distributed in the order endocarp > seed coat > embryo, with the content in the endocarp being about 132-fold higher than in the seed coat and embryo. Total ABA content of seeds subjected to warm or cold stratification, or both, was 8.7- to 14.0-fold lower than that of fresh seeds. Low contents of endogenous GA(1), GA(3), GA(7) and GA(20), but elevated contents of GA(4), were found in the seed coats and endocarps of warm plus cold stratified seeds and in the seed coats and embryos of newly germinated seeds. These observations, coupled with the finding that GA stimulated

  2. Clostridiaceae and Enterobacteriaceae as active fermenters in earthworm gut content.

    PubMed

    Wüst, Pia K; Horn, Marcus A; Drake, Harold L

    2011-01-01

    The earthworm gut provides ideal in situ conditions for ingested heterotrophic soil bacteria capable of anaerobiosis. High amounts of mucus- and plant-derived saccharides such as glucose are abundant in the earthworm alimentary canal, and high concentrations of molecular hydrogen (H(2)) and organic acids in the alimentary canal are indicative of ongoing fermentations. Thus, the central objective of this study was to resolve potential links between fermentations and active fermenters in gut content of the anecic earthworm Lumbricus terrestris by 16S ribosomal RNA (rRNA)-based stable isotope probing, with [(13)C]glucose as a model substrate. Glucose consumption in anoxic gut content microcosms was rapid and yielded soluble organic compounds (acetate, butyrate, formate, lactate, propionate, succinate and ethanol) and gases (carbon dioxide and H(2)), products indicative of diverse fermentations in the alimentary canal. Clostridiaceae and Enterobacteriaceae were users of glucose-derived carbon. On the basis of the detection of 16S rRNA, active phyla in gut contents included Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Proteobacteria, Tenericutes and Verrucomicrobia, taxa common to soils. On the basis of a 16S rRNA gene similarity cutoff of 87.5%, 82 families were detected, 17 of which were novel family-level groups. These findings (a) show the large diversity of soil taxa that might be active during gut passage, (b) show that Clostridiaceae and Enterobacteriaceae (fermentative subsets of these taxa) are selectively stimulated by glucose and might therefore be capable of consuming mucus- and plant-derived saccharides during gut passage and (c) indicate that ingested obligate anaerobes and facultative aerobes from soil can concomitantly metabolize the same source of carbon.

  3. Competition for in vitro (/sup 3/H)gibberellin A/sub 4/ binding in cucumber by gibberellins and their derivatives. [Cucumis sativus L. cv National Pickling

    SciTech Connect

    Yalpani, N.; Srivastava, L.M.

    1985-12-01

    The gibberellin (GA) binding properties of a cytosol fraction from hypocotyls of cucumber (Cucumis sativus L. cv National Pickling) were examined using a DEAE filter paper assay, (/sup 3/H)GA/sub 4/, and over 20 GAs, GA derivatives and other growth regulators. The results demonstrate structural specificity of the binding protein for ..gamma..-lactonic C-19 GAs with a 3 ..beta..-hydroxyl and a C-6 carboxyl group. Additional hydroxylations of the A, C, or D ring of the ent-gibberellane skeleton and methylation of the C-6 carboxyl impede or abolish binding affinity. Bioassay data are generally supported by the in vitro results but significantly GA/sub 9/ and GA/sub 36/, both considered to be precursors of GA/sub 4/ in cucumber, show no affinity for the binding protein. The results are discussed in relation to the active site of the putative GA/sub 4/ receptor in cucumber.

  4. Genotype, location, and year influence antioxidant activity, carotenoid content, phenolic content, and composition in specialty potatoes.

    PubMed

    Reddivari, Lavanya; Hale, Anna L; Miller, J Creighton

    2007-10-03

    The influence of genotype, location, and year on antioxidant activity (AOA), total phenolics (TP), total carotenoids (TC), and phenolic composition was studied using specialty (colored) potatoes ( Solanum tuberosum L.) from the Texas Potato Variety Development Program. Twenty-five potato genotypes were grown at two Texas locations (McCook and Dalhart) and in two years (2003 and 2004). The AOA, TP, and TC differed significantly with genotype (G), location (L), and year (Y). Phenolic composition differed significantly among genotypes and between locations. The AOA, TP, and chlorogenic acid content were significantly correlated with one another. Genotypic effects were significant for all parameters measured and were larger than location and year effects. Interaction effects (G x L and G x L x Y) were significant for most parameters, but were relatively smaller than genotypic effects. Lutein and violaxanthin were the major carotenoids identified, and genotypes differed significantly in their carotenoid content. Genotypes CO112F2-2P/P and ATTX98013-1R/R were stable between locations and years with high AOA and TP, suggesting that they could be used as parents in breeding varieties with improved health benefits.

  5. Further identification of endogenous gibberellins in the shoots of pea, line G2

    SciTech Connect

    Halinska, A.; Davies, P.J.; Lee, J.W.; Zhu, Yuxian )

    1989-12-01

    To interpret the metabolism of radiolabeled gibberellins A{sub 12}-aldehyde and A{sub 12} in shoots of pea (Pisum sativum L.), the identity of the radiolabeled peaks has to be determined and the endogenous presence of the gibberellins demonstrated. High specific activity ({sup 14}C)GA{sub 12} and ({sup 14}C)GA{sub 12}-aldehyde were synthesized using a pumpkin endosperm enzyme preparation, and purified by high performance liquid chromatography (HPLC). ({sup 14}C)GA{sub 12} was supplied to upper shoots of pea, line G2, to produce radiolabeled metabolites on the 13-OH pathway. Endogenous compounds copurifying with the ({sup 14}C)GAs on HPLC were analyzed by gas chromatography-mass spectrometry. The endogenous presence of GA{sub 53}, GA{sub 44}, GA{sub 19} and GA{sub 20} was demonstrated and their HPLC peak identity ascertained. The {sup 14}C was progressively diluted in GAs further down the pathway, proportional to the levels found in the tissue and inversely proportional to the speed of metabolism, ranging from 63% in GA{sub 53} to 4% in GA{sub 20}. Calculated levels of GA{sub 20}, GA{sub 19}, GA{sub 44}, and GA{sub 53} were 42, 8, 10, and 0.5 nanograms/gram, respectively.

  6. Role of gibberellin in the growth response of submerged deep water rice

    SciTech Connect

    Raskin, I.; Kende, H.

    1984-12-01

    The authors have shown previously that ethylene, which accumulates in the air spaces of submerged stem sections of rice (Oryza sativa L. cv Habiganj Aman II), is involved in regulating the growth response caused by submergence. The role of gibberellins in the submergence response was studied using tetcyclacis (TCY), a new plant growth retardant, which inhibits gibberellin biosynthesis. Stem sections excised from plants that had been watered with a solution of 1 micromolar TCY for 7 to 10 days did not elongate when submerged in the same solution or when exposed to 1 microliter per liter ethylene in air. Gibberellic acid (GA/sub 3/) at 0.3 micromolar overcame the effect of TCY and restored the rapid internodal elongation in submerged and ethylene-treated sections to the levels observed in control sections that had not been treated with TCY. The effect of 0.01 to 0.2 micromolar GA/sub 3/ on internodal elongation was enhanced two- to eight-fold when 1 microliter per liter ethylene was added to their passing through the chamber in which the sections were incubated. GA/sub 3/ and ethylene caused a similar increase in cell division and cell elongation in rice internodes. Thus, ethylene may cause internodal elongation in rice by increasing the activity of endogenous GAs. In internodes from which the leaf sheath had been peeled off, growth in response to submergence, ethylene and GA/sub 3/ was severely inhibited by light. 8 references, 3 figures, 2 tables.

  7. Mutations at the SPINDLY locus of Arabidopsis alter gibberellin signal transduction.

    PubMed Central

    Jacobsen, S E; Olszewski, N E

    1993-01-01

    Three independent recessive mutations at the SPINDLY (SPY) locus of Arabidopsis confer resistance to the gibberellin (GA) biosynthesis inhibitor paclobutrazol. Relative to wild type, spy mutants exhibit longer hypocotyls, leaves that are a lighter green color, increased stem elongation, early flowering, parthenocarpy, and partial male sterility. All of these phenotypes are also observed when wild-type Arabidopsis plants are repeatedly treated with gibberellin A3 (GA3). The spy-1 allele is partially epistatic to the ga1-2 mutation, which causes GA deficiency. In addition, the spy-1 mutation can simultaneously suppress the effects of the ga1-2 mutation and paclobutrazol treatment, which inhibit different steps in the GA biosynthesis pathway. This observation suggests that spy-1 activates a basal level of GA signal transduction that is independent of GA. Furthermore, results from GA3 dose-response experiments suggest that GA3 and spy-1 interact in an additive manner. These results are consistent with models in which the SPY gene product regulates a portion of the GA signal transduction pathway. PMID:8400871

  8. Olive Mill Waste Extracts: Polyphenols Content, Antioxidant, and Antimicrobial Activities

    PubMed Central

    Leouifoudi, Inass; Harnafi, Hicham; Zyad, Abdelmajid

    2015-01-01

    Natural polyphenols extracts have been usually associated with great bioactive properties. In this work, we investigated in vitro antioxidant and antimicrobial potential of the phenolic olive mill wastewater extracts (OWWE) and the olive cake extracts (OCE). Using the Folin Ciocalteux method, OWWE contained higher total phenol content compared to OCE (8.90 ± 0.728 g/L versus 0.95 ± 0.017 mg/g). The phenolic compounds identification was carried out with a performance liquid chromatograph coupled to tandem mass spectrometry equipment (HPLC-ESI-MS). With this method, a list of polyphenols from OWWE and OCE was obtained. The antioxidant activity was measured in aqueous (DPPH) and emulsion (BCBT) systems. Using the DPPH assay, the results show that OWWE was more active than OCE and interestingly the extracts originating from mountainous areas were more active than those produced from plain areas (EC50 = 12.1 ± 5.6 μg/mL; EC50 = 157.7 ± 34.9 μg/mL, resp.). However, when the antioxidant activity was reversed in the BCBT, OCE produced from plain area was more potent than mountainous OCE. Testing by the gel diffusion assay, all the tested extracts have showed significant spectrum antibacterial activity against Staphylococcus aureus, whereas the biophenols extracts showed more limited activity against Escherichia coli and Streptococcus faecalis. PMID:26693221

  9. Gibberellin mediates the development of gelatinous fibres in the tension wood of inclined Acacia mangium seedlings.

    PubMed

    Nugroho, Widyanto Dwi; Nakaba, Satoshi; Yamagishi, Yusuke; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

    2013-11-01

    Gibberellin stimulates negative gravitropism and the formation of tension wood in tilted Acacia mangium seedlings, while inhibitors of gibberellin synthesis strongly inhibit the return to vertical growth and suppress the formation of tension wood. To characterize the role of gibberellin in tension wood formation and gravitropism, this study investigated the role of gibberellin in the development of gelatinous fibres and in the changes in anatomical characteristics of woody elements in Acacia mangium seedlings exposed to a gravitational stimulus. Gibberellin, paclobutrazol and uniconazole-P were applied to the soil in which seedlings were growing, using distilled water as the control. Three days after the start of treatment, seedlings were inclined at 45 ° to the vertical and samples were harvested 2 months later. The effects of the treatments on wood fibres, vessel elements and ray parenchyma cells were analysed in tension wood in the upper part of inclined stems and in the opposite wood on the lower side of inclined stems. Application of paclobutrazol or uniconazole-P inhibited the increase in the thickness of gelatinous layers and prevented the elongation of gelatinous fibres in the tension wood of inclined stems. By contrast, gibberellin stimulated the elongation of these fibres. Application of gibberellin and inhibitors of gibberellin biosynthesis had only minor effects on the anatomical characteristics of vessel and ray parenchyma cells. The results suggest that gibberellin is important for the development of gelatinous fibres in the tension wood of A. mangium seedlings and therefore in gravitropism.

  10. Exogenous gibberellin altered morphology, anatomic and transcriptional regulatory networks of hormones in carrot root and shoot.

    PubMed

    Wang, Guang-Long; Que, Feng; Xu, Zhi-Sheng; Wang, Feng; Xiong, Ai-Sheng

    2015-12-15

    Gibberellins stimulate cell elongation and expansion during plant growth and development. Carrot is a root plant with great value and undergoes obvious alteration in organ size over the period of plant growth. However, the roles of gibberellins in carrot remain unclear. To investigate the effects of gibberelliins on the growth of carrot, we treated carrot plants with gibberellic acid 3 (GA3) or paclobutrazol (a gibberellin inhibitor). The results found that GA3 dramatically reduced the root growth but stimulated the shoot growth of carrot. It also significantly promoted xylem development in the tuberous root of carrot. In addition, transcript levels of genes related to gibberellins, auxin, cytokinins, abscisic acid and brassinolides were altered in response to increased or reduced gibberellins. The inhibited tuberous root growth but enhanced shoot growth in plants treated with GA3 can be principally attributed to the changes in the xylem development of carrot roots. Negative feedback regulation mechanism of gibberellin biosynthesis also occurred in response to altered gibberellin accumulation. Gibberellins may interact with other hormones to regulate carrot plant growth through crosstalk mechanisms. This study provided novel insights into the functions of gibberellins in the growth and development of carrot.

  11. Gibberellins in Penicillium strains: Challenges for endophyte-plant host interactions under salinity stress.

    PubMed

    Leitão, Ana Lúcia; Enguita, Francisco J

    2016-02-01

    The genus Penicillium is one of the most versatile "mycofactories", comprising some species able to produce gibberellins, bioactive compounds that can modulate plant growth and development. Although plants have the ability to synthesize gibberellins, their levels are lower when plants are under salinity stress. It has been recognized that detrimental abiotic conditions, such as saline stress, have negative effects on plants, being the availability of bioactive gibberellins a critical factor for their growth under this conditions. This review summarizes the interplay existing between endophytic Penicillium strains and plant host interactions, with focus on bioactive gibberellins production as a fungal response that allows plants to overcome salinity stress.

  12. Increased Nicotiana tabacum fitness through positive regulation of carotenoid, gibberellin and chlorophyll pathways promoted by Daucus carota lycopene β-cyclase (Dclcyb1) expression.

    PubMed

    Moreno, J C; Cerda, A; Simpson, K; Lopez-Diaz, I; Carrera, E; Handford, M; Stange, C

    2016-04-01

    Carotenoids, chlorophylls and gibberellins are derived from the common precursor geranylgeranyl diphosphate (GGPP). One of the enzymes in carotenoid biosynthesis is lycopene β-cyclase (LCYB) that catalyzes the conversion of lycopene into β-carotene. In carrot, Dclcyb1 is essential for carotenoid synthesis in the whole plant. Here we show that when expressed in tobacco, increments in total carotenoids, β-carotene and chlorophyll levels occur. Furthermore, photosynthetic efficiency is enhanced in transgenic lines. Interestingly, and contrary to previous observations where overexpression of a carotenogenic gene resulted in the inhibition of the synthesis of gibberellins, we found raised levels of active GA4 and the concommitant increases in plant height, leaf size and whole plant biomass, as well as an early flowering phenotype. Moreover, a significant increase in the expression of the key carotenogenic genes, Ntpsy1, Ntpsy2 and Ntlcyb, as well as those involved in the synthesis of chlorophyll (Ntchl), gibberellin (Ntga20ox, Ntcps and Ntks) and isoprenoid precursors (Ntdxs2 and Ntggpps) was observed. These results indicate that the expression of Dclcyb1 induces a positive feedback affecting the expression of isoprenoid gene precursors and genes involved in carotenoid, gibberellin and chlorophyll pathways leading to an enhancement in fitness measured as biomass, photosynthetic efficiency and carotenoid/chlorophyll composition.

  13. Increased Nicotiana tabacum fitness through positive regulation of carotenoid, gibberellin and chlorophyll pathways promoted by Daucus carota lycopene β-cyclase (Dclcyb1) expression

    PubMed Central

    Moreno, J.C.; Cerda, A.; Simpson, K.; Lopez-Diaz, I.; Carrera, E; Handford, M.; Stange, C.

    2016-01-01

    Carotenoids, chlorophylls and gibberellins are derived from the common precursor geranylgeranyl diphosphate (GGPP). One of the enzymes in carotenoid biosynthesis is lycopene β-cyclase (LCYB) that catalyzes the conversion of lycopene into β-carotene. In carrot, Dclcyb1 is essential for carotenoid synthesis in the whole plant. Here we show that when expressed in tobacco, increments in total carotenoids, β-carotene and chlorophyll levels occur. Furthermore, photosynthetic efficiency is enhanced in transgenic lines. Interestingly, and contrary to previous observations where overexpression of a carotenogenic gene resulted in the inhibition of the synthesis of gibberellins, we found raised levels of active GA4 and the concommitant increases in plant height, leaf size and whole plant biomass, as well as an early flowering phenotype. Moreover, a significant increase in the expression of the key carotenogenic genes, Ntpsy1, Ntpsy2 and Ntlcyb, as well as those involved in the synthesis of chlorophyll (Ntchl), gibberellin (Ntga20ox, Ntcps and Ntks) and isoprenoid precursors (Ntdxs2 and Ntggpps) was observed. These results indicate that the expression of Dclcyb1 induces a positive feedback affecting the expression of isoprenoid gene precursors and genes involved in carotenoid, gibberellin and chlorophyll pathways leading to an enhancement in fitness measured as biomass, photosynthetic efficiency and carotenoid/chlorophyll composition. PMID:26893492

  14. Gibberellins and the Legume-Rhizobium Symbiosis 1

    PubMed Central

    Dobert, Raymond C.; Rood, Stewart B.; Zanewich, Karen; Blevins, Dale G.

    1992-01-01

    Lima bean (Phaseolus lunatus L.) plants inoculated with Bradyrhizobium sp. strain 127E14 displayed a period of marked internode elongation that was not observed in plants inoculated with other compatible bradyrhizobia, including strain 127E15. When strain 127E14 nodulated an alternate host, cowpea (Vigna unguiculata L. Walp), a similar, although less dramatic growth response induced by the bacteria was observed. It has been speculated that the elongative growth promotion brought about by inoculation with strain 127E14 is mediated by gibberellins (GAs). Using deuterated internal standards and gas chromatography-mass spectroscopy analysis, we have quantified the levels of GA1, GA20, GA19, and GA44 in nodules and stems of two varieties of lima bean (bush and pole) and one variety of cowpea that were inoculated with either strain 127E14 or 127E15. In nodules formed by strain 127E14 on lima bean, endogenous levels of GA20 and GA19 were 10 to 40 times higher (35-88 ng/g dry weight) than amounts found in nodules formed by strain 127E15 (2.2-3.9 ng/g dry weight). Relative amounts of GA44 were also higher (4- to 11-fold) in 127E14 nodules, but this increase was less pronounced. The rhizobial-induced increase of these GAs in the nodule occurred in both pole and bush varieties and seemed to be independent of host morphology. Regardless of rhizobial inoculum, levels of the “bioactive” GA1 in the nodule (0.3-1.1 ng/g dry weight) were similar. In cowpea nodules, a similar, although smaller, difference in GA content due to rhizobial strain was observed. The concentration of GA1 in lima bean stems was generally higher than that observed in the nodule, whereas concentrations of the other GAs measured were lower. In contrast with the nodule, GA concentrations in lima bean stems were not greater in plants inoculated with strain 127E14, and in some cases the slower growing plants inoculated with strain 127E15 actually had higher levels of GA20, GA19, and GA44. Thus, there were

  15. Exogenous gibberellin enhances secondary xylem development and lignification in carrot taproot.

    PubMed

    Wang, Guang-Long; Que, Feng; Xu, Zhi-Sheng; Wang, Feng; Xiong, Ai-Sheng

    2017-03-01

    Gibberellins (GAs) are important growth regulators involved in plant development processes. However, limited information is known about the relationship between GA and xylogenesis in carrots. In this study, carrot roots were treated with GA3. The effects of applied GA3 on root growth, xylem development, and lignin accumulation were then investigated. Results indicated that GA treatment dose-dependently inhibited carrot root growth. The cell wall significantly thickened in the xylem parenchyma. Autofluorescence analysis with ultraviolet (UV) excitation indicated that these cells became lignified because of long-term GA3 treatment. Moreover, lignin content increased in the roots, and the transcripts of lignin biosynthesis genes were altered in response to applied GA3. Our data indicate that GA may play important roles in xylem growth and lignification in carrot roots. Further studies shall focus on regulating plant lignification, which may be achieved by modifying GA levels within plant tissues.

  16. Ectopic Expression of Pumpkin Gibberellin Oxidases Alters Gibberellin Biosynthesis and Development of Transgenic Arabidopsis Plants1

    PubMed Central

    Radi, Abeer; Lange, Theo; Niki, Tomoya; Koshioka, Masaji; Lange, Maria João Pimenta

    2006-01-01

    Immature pumpkin (Cucurbita maxima) seeds contain gibberellin (GA) oxidases with unique catalytic properties resulting in GAs of unknown function for plant growth and development. Overexpression of pumpkin GA 7-oxidase (CmGA7ox) in Arabidopsis (Arabidopsis thaliana) resulted in seedlings with elongated roots, taller plants that flower earlier with only a little increase in bioactive GA4 levels compared to control plants. In the same way, overexpression of the pumpkin GA 3-oxidase1 (CmGA3ox1) resulted in a GA overdose phenotype with increased levels of endogenous GA4. This indicates that, in Arabidopsis, 7-oxidation and 3-oxidation are rate-limiting steps in GA plant hormone biosynthesis that control plant development. With an opposite effect, overexpression of pumpkin seed-specific GA 20-oxidase1 (CmGA20ox1) in Arabidopsis resulted in dwarfed plants that flower late with reduced levels of GA4 and increased levels of physiological inactive GA17 and GA25 and unexpected GA34 levels. Severe dwarfed plants were obtained by overexpression of the pumpkin GA 2-oxidase1 (CmGA2ox1) in Arabidopsis. This dramatic change in phenotype was accompanied by a considerable decrease in the levels of bioactive GA4 and an increase in the corresponding inactivation product GA34 in comparison to control plants. In this study, we demonstrate the potential of four pumpkin GA oxidase-encoding genes to modulate the GA plant hormone pool and alter plant stature and development. PMID:16384902

  17. The dominant non-gibberellin-responding dwarf mutant (D8) of maize accumulates native gibberellins

    PubMed Central

    Fujioka, Shozo; Yamane, Hisakazu; Spray, Clive R.; Katsumi, Masayuki; Phinney, Bernard O.; Gaskin, Paul; MacMillan, Jake; Takahashi, Nobutaka

    1988-01-01

    The endogenous gibberellins (GAs) were examined from young vegetative shoots of the dominant mutant, Dwarf-8, a GA-nonresponder, and normal maize; GA44, GA17, GA19, GA20, GA29, GA1, and GA8, members of the early-13-hydroxylation pathway, were identified from both kinds of shoots by full-scan mass spectra and Kovats retention indices. In addition, we report the identification of 3-epi-GA1, GA3, GA4, GA5, GA7, GA9, GA12, GA15, GA24, GA34, and GA53 by using the same criteria. [1,7,12,18-14C4]GA53 and -GA44, [17-2H2]GA19, and [17-13C,3H2]GA20, -GA29, -GA1, -GA8, and -GA5 were used as internal standards to determine the endogenous levels of these GAs by measurement of isotope dilution, using capillary gas chromatography and selected ion monitoring. Shoots of Dwarf-8 accumulate relatively high levels of GA20, GA1, and GA8. The accumulation of GA1 appears to be related to gene dosage. Since Dwarf-8 contains the same pattern of GAs as normals (including GA1 and GA3), the genetic control point probably lies after GA1 (and GA3). Thus Dwarf-8 may be a GA receptor mutant or a mutant that controls a product downstream from the binding of the bioactive GA to a receptor. Images PMID:16594001

  18. The role of gibberellins in improving the resistance of tebuconazole-coated maize seeds to chilling stress by microencapsulation

    NASA Astrophysics Data System (ADS)

    Yang, Lijuan; Yang, Daibin; Yan, Xiaojing; Cui, Li; Wang, Zhenying; Yuan, Huizhu

    2016-11-01

    Chilling stress during germination often causes severe injury. In the present study, maize seed germination and shoot growth under chilling stress were negatively correlated with the dose of tebuconazole in an exponential manner as predicted by the model Y = A + B × e(-x/k). Microencapsulation was an effective means of eliminating potential phytotoxic risk. The gibberellins (GAs) contents were higher after microencapsulation treatment than after conventional treatment when the dose of tebuconazole was higher than 0.12 g AI (active ingredient) kg-1 seed. Further analysis indicated that microencapsulation can stimulate ent-kaurene oxidase (KO) activity to some extent, whereas GA 3-oxidase (GA3ox) and GA 2-oxidase (GA2ox) activities remained similar to those in the control. Genes encoding GA metabolic enzymes exhibited different expression patterns. Transcript levels of ZmKO1 increased in the microcapsule treatments compared to the control. Even when incorporated into microcapsules, tebuconazole led to the upregulation of ZmGA3ox1 at doses of less than 0.12 g AI kg-1 seed and to the upregulation of ZmGA3ox2 when the dose was higher than 0.12 g AI kg-1 seed. With increasing doses of microencapsulated tebuconazole, the transcript levels of ZmGA2ox4, ZmGA2ox5 and ZmGA2ox6 exhibited upward trends, whereas the transcript levels of ZmGA2ox7 exhibited a downward trend.

  19. The role of gibberellins in improving the resistance of tebuconazole-coated maize seeds to chilling stress by microencapsulation

    PubMed Central

    Yang, Lijuan; Yang, Daibin; Yan, Xiaojing; Cui, Li; Wang, Zhenying; Yuan, Huizhu

    2016-01-01

    Chilling stress during germination often causes severe injury. In the present study, maize seed germination and shoot growth under chilling stress were negatively correlated with the dose of tebuconazole in an exponential manner as predicted by the model Y = A + B × e(−x/k). Microencapsulation was an effective means of eliminating potential phytotoxic risk. The gibberellins (GAs) contents were higher after microencapsulation treatment than after conventional treatment when the dose of tebuconazole was higher than 0.12 g AI (active ingredient) kg−1 seed. Further analysis indicated that microencapsulation can stimulate ent-kaurene oxidase (KO) activity to some extent, whereas GA 3-oxidase (GA3ox) and GA 2-oxidase (GA2ox) activities remained similar to those in the control. Genes encoding GA metabolic enzymes exhibited different expression patterns. Transcript levels of ZmKO1 increased in the microcapsule treatments compared to the control. Even when incorporated into microcapsules, tebuconazole led to the upregulation of ZmGA3ox1 at doses of less than 0.12 g AI kg−1 seed and to the upregulation of ZmGA3ox2 when the dose was higher than 0.12 g AI kg−1 seed. With increasing doses of microencapsulated tebuconazole, the transcript levels of ZmGA2ox4, ZmGA2ox5 and ZmGA2ox6 exhibited upward trends, whereas the transcript levels of ZmGA2ox7 exhibited a downward trend. PMID:27819337

  20. Promoting Physical Activity through Priming the Content of Motivation.

    PubMed

    St Quinton, Tom

    2017-01-01

    Non-conscious processes are important in influencing the performance of a number of behaviors, such as physical activity. One way that such processes can be influenced is through priming. Despite this, approaches within health psychology have predominantly focused on reflective processes with a number of psychological theories dedicated to identifying the predictors of intention. In doing so, critical beliefs and thoughts are first identified and then altered within interventions. Such work has shown limited effectiveness, however, with a gap apparent between what one intends to do and what subsequently ensues. Although there have been attempts to bridge this gap, such as theoretical integration, recent efforts include priming implicit processes. The aim of this commentary is to demonstrate the potential effectiveness of priming non-conscious processes and to suggest that the content of motivation should also succumb to priming influences. This brief review suggests that priming one of the most influential conscious processes, that of self-efficacy, could demonstrate particular effectiveness in promoting physical activity. Thus, the main purpose of the article is to suggest that the content of implicit processes as well their more traditional conscious counterparts may provide useful intervention targets. To achieve this, the article will first introduce the role of non-conscious processes and behavioral priming. Following this, the more common reflective processes will be outlined as well as attempts at theoretical integration. Finally, the article will identify studies priming non-conscious processes and will then suggest priming self-efficacy.

  1. Evidence for a Gibberellin Biosynthetic Origin of Ceratopteris Antheridiogen 1

    PubMed Central

    Warne, Thomas R.; Hickok, Leslie G.

    1989-01-01

    The species-specific chemical messenger, antheridiogen ACe, mediates the differentiation of male gametophytes in the fern Ceratopteris. In order to investigate the biochemical origin of antheridiogen, the effect of the inhibitors, 2′-isopropyl-4′-(trimethylammoniumchloride)-5′ -methylphenylpiperidine-1-carboxylate (AMO-1618), 2-chloroethyl trimethylammonium chloride (CCC), and α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidine methyl alcohol (ancymidol) on gametophytic sex expression was determined in C. richardii. Both AMO-1618 and ancymidol blocked the production of male gametophytes in three genetically defined strains of C. richardii that exhibit different sensitivities to antheridiogen. Antheridiogen supplementation overcame inhibition by AMO-1618 and ancymidol, except in one strain (HaC18) that is insensitive to antheridiogen supplementation. These data suggest that the synthesis of Ceratopteris antheridiogen, a taxon that is insensitive to exogenously supplied gibberellins, occurs via a pathway that may include steps in common with gibberellin biosynthesis or involves similar reactions. PMID:16666578

  2. Gibberellins Producing Endophytic Fungus Porostereum spadiceum AGH786 Rescues Growth of Salt Affected Soybean

    PubMed Central

    Hamayun, Muhammad; Hussain, Anwar; Khan, Sumera A.; Kim, Ho-Youn; Khan, Abdul L.; Waqas, Muhammad; Irshad, Muhammad; Iqbal, Amjad; Rehman, Gauhar; Jan, Samin; Lee, In-Jung

    2017-01-01

    In the pursuit of sustainable agriculture through environment and human health friendly practices, we evaluated the potential of a novel gibberellins (GAs) producing basidiomycetous endophytic fungus Porostereum spadiceum AGH786, for alleviating salt stress and promoting health benefits of soybean. Soybean seedlings exposed to different levels of NaCl stress (70 and 140 mM) under greenhouse conditions, were inoculated with the AGH786 strain. Levels of phytohormones including GAs, JA and ABA, and isoflavones were compared in control and the inoculated seedlings to understand the mechanism through which the stress is alleviated. Gibberellins producing endophytic fungi have been vital for promoting plant growth under normal and stress conditions. We report P. spadiceum AGH786 as the ever first GAs producing basidiomycetous fungus capable of producing six types of GAs. In comparison to the so for most efficient GAs producing Gibberella fujikuroi, AGH786 produced significantly higher amount of the bioactive GA3. Salt-stressed phenotype of soybean seedlings was characterized by low content of GAs and high amount of ABA and JA with reduced shoot length, biomass, leaf area, chlorophyll contents, and rate of photosynthesis. Mitigation of salt stress by AGH786 was always accompanied by high GAs, and low ABA and JA, suggesting that this endophytic fungus reduces the effect of salinity by modulating endogenous phytohormones of the seedlings. Additionally, this strain also enhanced the endogenous level of two isoflavones including daidzen and genistein in soybean seedlings under normal as well as salt stress conditions as compared to their respective controls. P. spadiceum AGH786 boosted the NaCl stress tolerance and growth in soybean, by modulating seedlings endogenous phytohormones and isoflavones suggesting a valuable contribution of this potent fungal biofertilizer in sustainable agriculture in salt affected soils. PMID:28473818

  3. Gibberellins Producing Endophytic Fungus Porostereum spadiceum AGH786 Rescues Growth of Salt Affected Soybean.

    PubMed

    Hamayun, Muhammad; Hussain, Anwar; Khan, Sumera A; Kim, Ho-Youn; Khan, Abdul L; Waqas, Muhammad; Irshad, Muhammad; Iqbal, Amjad; Rehman, Gauhar; Jan, Samin; Lee, In-Jung

    2017-01-01

    In the pursuit of sustainable agriculture through environment and human health friendly practices, we evaluated the potential of a novel gibberellins (GAs) producing basidiomycetous endophytic fungus Porostereum spadiceum AGH786, for alleviating salt stress and promoting health benefits of soybean. Soybean seedlings exposed to different levels of NaCl stress (70 and 140 mM) under greenhouse conditions, were inoculated with the AGH786 strain. Levels of phytohormones including GAs, JA and ABA, and isoflavones were compared in control and the inoculated seedlings to understand the mechanism through which the stress is alleviated. Gibberellins producing endophytic fungi have been vital for promoting plant growth under normal and stress conditions. We report P. spadiceum AGH786 as the ever first GAs producing basidiomycetous fungus capable of producing six types of GAs. In comparison to the so for most efficient GAs producing Gibberella fujikuroi, AGH786 produced significantly higher amount of the bioactive GA3. Salt-stressed phenotype of soybean seedlings was characterized by low content of GAs and high amount of ABA and JA with reduced shoot length, biomass, leaf area, chlorophyll contents, and rate of photosynthesis. Mitigation of salt stress by AGH786 was always accompanied by high GAs, and low ABA and JA, suggesting that this endophytic fungus reduces the effect of salinity by modulating endogenous phytohormones of the seedlings. Additionally, this strain also enhanced the endogenous level of two isoflavones including daidzen and genistein in soybean seedlings under normal as well as salt stress conditions as compared to their respective controls. P. spadiceum AGH786 boosted the NaCl stress tolerance and growth in soybean, by modulating seedlings endogenous phytohormones and isoflavones suggesting a valuable contribution of this potent fungal biofertilizer in sustainable agriculture in salt affected soils.

  4. Gibberellins in Suspensors of Phaseolus coccineus L. Seeds 1

    PubMed Central

    Picciarelli, Piero; Alpi, Amedeo

    1986-01-01

    Analysis of extracts from 6300 (1.2 grams fresh weight) Phaseolus coccineus suspensors by combined gas chromatography-mass spectrometry has demonstrated the presence of five C19-gibberellins, GA1, GA4, GA5, GA6, GA8, and one C20-GA, GA44. The major GAs present were GA1 and GA8. Data are discussed in relation to previous results obtained in P. coccineus seed as well as in the embryo-suspensor system. PMID:16665010

  5. An investigation of the theoretical content of physical activity brochures

    PubMed Central

    Gainforth, Heather L.; Barg, Carolyn J.; Latimer, Amy E.; Schmid, Kristina L.; O'Malley, Deborah; Salovey, Peter

    2011-01-01

    New evidence-based physical activity guidelines and recommendations for constructing messages supplementing the guidelines have been put forth. As well, recent reviewshave identified theoretical constructs that hold promise as targets for intervention: self-regulation, outcome expectancies and self-efficacy. The purpose of this study was to examine the integration of messages targeting self-regulation, self-efficacy and outcome expectancies in existing physical activity brochures. Twenty-two PA brochures from Canadian and American National Health Organizations were assessed for their use self-efficacy, self-regulatory processes and outcome expectancies. Brochures were analyzed line-by-line using a modified version of the validated Content Analysis Approach to Theory-Specified Persuasive Educational Communication (CAATSPEC; Abraham et al., 2007). One third of the brochures were coded by two independent raters coded a third of the brochures (n = 7). Inter-rater reliability was acceptable for 17 of the 20 categories (rs> .79). Discrepancies in all categories were discussed and agreement was reached. The remaining brochures were coded by one of the two raters. Usage of thethree key theoretical constructs accounted for only 36.43% of brochure content (20.23% self-efficacy, 10.40% outcome expectancies, 5.80% self-regulation). Brochures lacked the use of a variety of theoretical strategies, specifically goal-setting, planning and verbal persuasion and rarely highlighted the affective benefits of physical activity. In the future brochures should aim to place increased emphasis on self-regulation, self-efficacy, and affective outcome expectancies. PMID:22125418

  6. Endophytic Penicillium funiculosum LHL06 secretes gibberellin that reprograms Glycine max L. growth during copper stress

    PubMed Central

    2013-01-01

    Background Heavy metal pollution in crop fields is one of the major issues in sustainable agriculture production. To improve crop growth and reduce the toxic effects of metals is an ideal strategy. Understanding the resilience of gibberellins producing endophytic fungi associated with crop plants in metal contaminated agriculture fields could be an important step towards reducing agrochemical pollutions. In present study, it was aimed to screen and identify metal resistant endophyte and elucidate its role in rescuing crop plant growth and metabolism during metal stress. Results Fungal endophyte, Penicillium funiculosum LHL06, was identified to possess higher growth rate in copper (Cu) and cadmium contaminated mediums as compared to other endophytes (Metarhizium anisopliae, Promicromonospora sp. and Exophiala sp.). P. funiculosum had high biosorption potential toward copper as compared to cadmium. An endophyte-metal-plant interaction was assessed by inoculating the host Glycine max L. plants with P. funiculosum during Cu (100 μM) stress. The Cu application adversely affected the biomass, chlorophyll and total protein content of non-inoculated control plants. The control plants unable to synthesis high carbon, hydrogen and nitrogen because the roots had lower access to phosphorous, potassium, sulphur and calcium during Cu treatment. Conversely, P. funiculosum-association significantly increased the plant biomass, root physiology and nutrients uptake to support higher carbon, hydrogen and nitrogen assimilation in shoot. The metal-removal potential of endophyte-inoculated plants was significantly higher than control as the endophyte-association mediated the Cu uptake via roots into shoots. The symbiosis rescued the host-plant growth by minimizing Cu-induced electrolytic leakage and lipid peroxidation while increasing reduces glutathione activities to avoid oxidative stress. P. funiculosum-association synthesized higher quantities of proline and glutamate as compared

  7. Endophytic Penicillium funiculosum LHL06 secretes gibberellin that reprograms Glycine max L. growth during copper stress.

    PubMed

    Khan, Abdul Latif; Lee, In-Jung

    2013-05-31

    Heavy metal pollution in crop fields is one of the major issues in sustainable agriculture production. To improve crop growth and reduce the toxic effects of metals is an ideal strategy. Understanding the resilience of gibberellins producing endophytic fungi associated with crop plants in metal contaminated agriculture fields could be an important step towards reducing agrochemical pollutions. In present study, it was aimed to screen and identify metal resistant endophyte and elucidate its role in rescuing crop plant growth and metabolism during metal stress. Fungal endophyte, Penicillium funiculosum LHL06, was identified to possess higher growth rate in copper (Cu) and cadmium contaminated mediums as compared to other endophytes (Metarhizium anisopliae, Promicromonospora sp. and Exophiala sp.). P. funiculosum had high biosorption potential toward copper as compared to cadmium. An endophyte-metal-plant interaction was assessed by inoculating the host Glycine max L. plants with P. funiculosum during Cu (100 μM) stress. The Cu application adversely affected the biomass, chlorophyll and total protein content of non-inoculated control plants. The control plants unable to synthesis high carbon, hydrogen and nitrogen because the roots had lower access to phosphorous, potassium, sulphur and calcium during Cu treatment. Conversely, P. funiculosum-association significantly increased the plant biomass, root physiology and nutrients uptake to support higher carbon, hydrogen and nitrogen assimilation in shoot. The metal-removal potential of endophyte-inoculated plants was significantly higher than control as the endophyte-association mediated the Cu uptake via roots into shoots. The symbiosis rescued the host-plant growth by minimizing Cu-induced electrolytic leakage and lipid peroxidation while increasing reduces glutathione activities to avoid oxidative stress. P. funiculosum-association synthesized higher quantities of proline and glutamate as compared to control. Stress

  8. Relationship between typhoon activity and upper ocean heat content

    NASA Astrophysics Data System (ADS)

    Wada, A.; Chan, J. C. L.

    2008-09-01

    A 44-year mean distribution of tropical cyclone heat potential (TCHP), a measure of the oceanic heat content from the surface to the 26°C-isotherm depth, shows that TCHP is locally high in the western North Pacific (WNP). TCHP varies on interannual time scales and has a relationship with tropical cyclone (TC) activity. The third mode of an empirical orthogonal function analysis of TCHP shows that an increase in the total number of TCs is accompanied with a warm central Pacific and cool WNP. Negative TCHP anomalies in the WNP suggest that an increase in total number of TCs results in cooling due to their passages. On the other hand, the first mode shows that the number of super typhoons increases in mature El Niño years. An increase in accumulated TCHP is related to the increase in the number of super typhoons due to long duration.

  9. Transcriptional changes of gibberellin oxidase genes in grapevines with or without gibberellin application during inflorescence development.

    PubMed

    Jung, Chan Jin; Hur, Youn Young; Jung, Sung-Min; Noh, Jung-Ho; Do, Gyung-Ran; Park, Seo-June; Nam, Jong-Chul; Park, Kyo-Sun; Hwang, Hae-Sung; Choi, Doil; Lee, Hee Jae

    2014-03-01

    The concept that gibberellin (GA) application on seeded grapevines induces seedlessness has been known for decades in viticulture. GA was applied to inflorescence clusters of seeded diploid grapevine cultivar 'Tamnara' (Vitis spp.) at 14 days before full bloom (DBF). Morphological and molecular effects of GA application were examined on the induction of parthenocarpic fruit development. With GA application, ovaries were enlarged and pollen tube growth was completely inhibited. Vitis GA oxidase enzymes, key determinants for GA level, were characterized through phylogenetic analysis with Arabidopsis GA oxidase enzymes. Five VvGA 20-oxidase (VvGA20ox), three VvGA 3-oxidase (VvGA3ox), and nine VvGA 2-oxidase (VvGA2ox) family proteins, and one VvGA methyltransferase (VvGAMT) and one Vitis cytochrome P450 714A1 proteins were identified, and their expression patterns were analyzed during inflorescence development from 14 DBF to 5 days after full bloom (DAF). VvGA2ox1, VvGA20ox3, and VvGA3ox2 were the most abundantly expressed genes in each gene family at 7, 5, and 2 DBF, respectively. Following GA application at 14 DBF inducing seedlessness, GA catabolic genes such as VvGAMT2, VvGA2ox3, and VvGA2ox4 were up-regulated at 12 DBF, full bloom, and 5 DAF, respectively. Conversely, most GA biosynthetic genes, VvGA20oxs and VvGA3oxs, were down-regulated at near full bloom, and the timing of their peak expression was changed. These results suggest that GA application at pre-bloom changes the GA biosynthesis into GA catabolic pathway at near full bloom by altering the transcription level and timing of GA oxidase genes during grapevine inflorescence development.

  10. Functional characterization of gibberellin oxidases from cucumber, Cucumis sativus L.

    PubMed

    Pimenta Lange, Maria João; Liebrandt, Anja; Arnold, Linda; Chmielewska, Sara-Miriam; Felsberger, André; Freier, Eduard; Heuer, Monika; Zur, Doreen; Lange, Theo

    2013-06-01

    Cucurbits have been used widely to elucidate gibberellin (GA) biosynthesis. With the recent availability of the genome sequence for the economically important cucurbit Cucumis sativus, sequence data became available for all genes potentially involved in GA biosynthesis for this species. Sixteen cDNAs were cloned from root and shoot of 3-d to 7-d old seedlings and from mature seeds of C. sativus. Two cDNAs code for GA 7-oxidases (CsGA7ox1, and -2), five for GA 20-oxidases (CsGA20ox1, -2, -3, -4, and -5), four for GA 3-oxidases (CsGA3ox1, -2, -3, and -4), and another five for GA 2-oxidases (CsGA2ox1, -2, -3, -4, and -5). Their enzymatic activities were investigated by heterologous expression of the cDNAs in Escherichia coli and incubation of the cell lysates with (14)C-labelled, D2-labelled, or unlabelled GA-substrates. The two GA 7-oxidases converted GA12-aldehyde to GA12 efficiently. CsGA7ox1 converted GA12 to GA14, to 15α-hydroxyGA12, and further to 15α-hydroxyGA14. CsGA7ox2 converted GA12 to its 12α-hydroxylated analogue GA111. All five GA 20-oxidases converted GA12 to GA9 as a major product, and to GA25 as a minor product. The four GA 3-oxidases oxidized the C19-GA GA9 to GA4 as the only product. In addition, three of them (CsGA3ox2, -3, and -4) converted the C20-GA GA12 to GA14. The GA 2-oxidases CsGA2ox1, -2, -3, and -4 oxidized the C19-GAs GA9 and GA4 to GA34 and GA51, respectively. CsGA2ox2, -3, and -4 converted GA51 and GA34 further to respective GA-catabolites. In addition to C19-GAs, CsGA2ox4 also converted the C20-GA GA12 to GA110. In contrast, CsGA2ox5 oxidized only the C20 GA12 to GA110 as the sole product. As shown for CsGA20ox1 and CsGA3ox1, similar reactions were catalysed with 13-hydroxlyated GAs as substrates. It is likely that these enzymes are also responsible for the biosynthesis of 13-hydroxylated GAs in vivo that occur at low levels in cucumber.

  11. Spatially distinct regulatory roles for gibberellins in the promotion of flowering of Arabidopsis under long photoperiods.

    PubMed

    Porri, Aimone; Torti, Stefano; Romera-Branchat, Maida; Coupland, George

    2012-06-01

    The plant growth regulator gibberellin (GA) contributes to many developmental processes, including the transition to flowering. In Arabidopsis, GA promotes this transition most strongly under environmental conditions such as short days (SDs) when other regulatory pathways that promote flowering are not active. Under SDs, GAs activate transcription of SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and LEAFY (LFY) at the shoot meristem, two genes encoding transcription factors involved in flowering. Here, the tissues in which GAs act to promote flowering were tested under different environmental conditions. The enzyme GIBBERELLIN 2 OXIDASE 7 (GA2ox7), which catabolizes active GAs, was overexpressed in most tissues from the viral CaMV 35S promoter, specifically in the vascular tissue from the SUCROSE TRANSPORTER 2 (SUC2) promoter or in the shoot apical meristem from the KNAT1 promoter. We find that under inductive long days (LDs), GAs are required in the vascular tissue to increase the levels of FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) mRNAs, which encode a systemic signal transported from the leaves to the meristem during floral induction. Similarly, impairing GA signalling in the vascular tissue reduces FT and TSF mRNA levels and delays flowering. In the meristem under inductive LDs, GAs are not required to activate SOC1, as reported under SDs, but for subsequent steps in floral induction, including transcription of genes encoding SQUAMOSA PROMOTER BINDING PROMOTER LIKE (SPL) transcription factors. Thus, GA has important roles in promoting transcription of FT, TSF and SPL genes during floral induction in response to LDs, and these functions are spatially separated between the leaves and shoot meristem.

  12. Gibberellin biosynthesis and signal transduction is essential for internode elongation in deepwater rice

    PubMed Central

    Ayano, Madoka; Kani, Takahiro; Kojima, Mikiko; Sakakibara, Hitoshi; Kitaoka, Takuya; Kuroha, Takeshi; Angeles-Shim, Rosalyn B; Kitano, Hidemi; Nagai, Keisuke; Ashikari, Motoyuki

    2014-01-01

    Under flooded conditions, the leaves and internodes of deepwater rice can elongate above the water surface to capture oxygen and prevent drowning. Our previous studies showed that three major quantitative trait loci (QTL) regulate deepwater-dependent internode elongation in deepwater rice. In this study, we investigated the age-dependent internode elongation in deepwater rice. We also investigated the relationship between deepwater-dependent internode elongation and the phytohormone gibberellin (GA) by physiological and genetic approach using a QTL pyramiding line (NIL-1 + 3 + 12). Deepwater rice did not show internode elongation before the sixth leaf stage under deepwater condition. Additionally, deepwater-dependent internode elongation occurred on the sixth and seventh internodes during the sixth leaf stage. These results indicate that deepwater rice could not start internode elongation until the sixth leaf stage. Ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the phytohormone contents showed a deepwater-dependent GA1 and GA4 accumulation in deepwater rice. Additionally, a GA inhibitor abolished deepwater-dependent internode elongation in deepwater rice. On the contrary, GA feeding mimicked internode elongation under ordinary growth conditions. However, mutations in GA biosynthesis and signal transduction genes blocked deepwater-dependent internode elongation. These data suggested that GA biosynthesis and signal transduction are essential for deepwater-dependent internode elongation in deepwater rice. Deepwater rice obtained the ability for rapid internode elongation to avoid drowning and adapt to flooded condition. How does it regulate internode elongation? Using both physiological and genetic approach, this paper shows that the plant hormone, gibberellin (GA) regulates internode elongation. PMID:24891164

  13. Myrigalone A inhibits Lepidium sativum seed germination by interference with gibberellin metabolism and apoplastic superoxide production required for embryo extension growth and endosperm rupture.

    PubMed

    Oracz, Krystyna; Voegele, Antje; Tarkowská, Danuse; Jacquemoud, Dominique; Turecková, Veronika; Urbanová, Terezie; Strnad, Miroslav; Sliwinska, Elwira; Leubner-Metzger, Gerhard

    2012-01-01

    Myrica gale L. (sweet gale) fruit leachate contains myrigalone A (MyA), a rare C-methylated dihydrochalcone and putative allelochemical, which is known to be a phytotoxin impeding seedling growth. We found that MyA inhibited Lepidium sativum L. seed germination in a dose-dependent manner. MyA did not affect testa rupture, but inhibited endosperm rupture and the transition to subsequent seedling growth. MyA inhibited micropylar endosperm cap (CAP) weakening and the increase in the growth potential of the radical/hypocotyl region (RAD) of the embryo, both being key processes required for endosperm rupture. We compared the contents of abscisic acid (ABA) and gibberellins in the tissues and found that the major bioactive forms of gibberellin in L. sativum seed tissues were GA(4) and GA(6), while GA(8) and GA(13) were abundant inactive metabolites. MyA did not appreciably affect the ABA contents, but severely interfered with gibberellin metabolism and signaling by inhibiting important steps catalyzed by GA3 oxidase, as well as by interfering with the GID1-type gibberellin signaling pathway. The hormonally and developmentally regulated formation of apoplastic superoxide radicals is important for embryo growth. Specific zones within the RAD were associated with accumulation of apoplastic superoxide radicals and endoreduplication indicative of embryo cell extension. MyA negatively affected both of these processes and acted as a scavenger of apoplastic reactive oxygen species. We propose that MyA is an allelochemical with a novel mode of action on seed germination.

  14. Overexpression of 20-Oxidase Confers a Gibberellin-Overproduction Phenotype in Arabidopsis

    PubMed Central

    Huang, Shihshieh; Raman, Anuradha S.; Ream, Joel E.; Fujiwara, Hideji; Cerny, R. Eric; Brown, Sherri M.

    1998-01-01

    In the gibberellin (GA) biosynthesis pathway, 20-oxidase catalyzes the oxidation and elimination of carbon-20 to give rise to C19-GAs. All bioactive GAs are C19-GAs. We have overexpressed a cDNA encoding 20-oxidase isolated from Arabidopsis seedlings in transgenic Arabidopsis plants. These transgenic plants display a phenotype that may be attributed to the overproduction of GA. The phenotype includes a longer hypocotyl, lighter-green leaves, increased stem elongation, earlier flowering, and decreased seed dormancy. However, the fertility of the transgenic plants is not affected. Increased levels of endogenous GA1, GA9, and GA20 were detected in seedlings of the transgenic line examined. GA4, which is thought to be the predominantly active GA in Arabidopsis, was not present at increased levels in this line. These results suggest that the overexpression of this 20-oxidase increases the levels of some endogenous GAs in transgenic seedlings, which causes the GA-overproduction phenotype. PMID:9808721

  15. Control of macaw palm seed germination by the gibberellin/abscisic acid balance.

    PubMed

    Bicalho, E M; Pintó-Marijuan, M; Morales, M; Müller, M; Munné-Bosch, S; Garcia, Q S

    2015-09-01

    The hormonal mechanisms involved in palm seed germination are not fully understood. To better understand how germination is regulated in Arecaceae, we used macaw palm (Acrocomia aculeata (Jacq.) Lodd. Ex Mart.) seed as a model. Endogenous hormone concentrations, tocopherol and tocotrienol and lipid peroxidation during germination were studied separately in the embryo and endosperm. Evaluations were performed in dry (D), imbibed (I), germinated (G) and non-germinated (NG) seeds treated (+GA3 ) or not treated (control) with gibberellins (GA). With GA3 treatment, seeds germinated faster and to a higher percentage than control seeds. The +GA3 treatment increased total bioactive GA in the embryo during germination relative to the control. Abscisic acid (ABA) concentrations decreased gradually from D to G in both tissues. Embryos of G seeds had a lower ABA content than NG seeds in both treatments. The GA/ABA ratio in the embryo was significantly higher in G than NG seeds. The +GA3 treatment did not significantly affect the GA/ABA ratio in either treatment. Cytokinin content increased from dry to germinated seeds. Jasmonic acid (JA) increased and 1-aminocyclopropane-1-carboylic acid (ACC) decreased after imbibition. In addition, α-tocopherol and α-tocotrienol decreased, while lipid peroxidation increased in the embryo during germination. We conclude that germination in macaw palm seed involves reductions in ABA content and, consequently, increased GA/ABA in the embryo. Furthermore, the imbibition process generates oxidative stress (as observed by changes in vitamin E and MDA).

  16. Lifting DELLA Repression of Arabidopsis Seed Germination by Nonproteolytic Gibberellin Signaling1[C][W][OPEN

    PubMed Central

    Ariizumi, Tohru; Hauvermale, Amber L.; Nelson, Sven K.; Hanada, Atsushi; Yamaguchi, Shinjiro; Steber, Camille M.

    2013-01-01

    DELLA repression of Arabidopsis (Arabidopsis thaliana) seed germination can be lifted either through DELLA proteolysis by the ubiquitin-proteasome pathway or through proteolysis-independent gibberellin (GA) hormone signaling. GA binding to the GIBBERELLIN-INSENSITIVE DWARF1 (GID1) GA receptors stimulates GID1-GA-DELLA complex formation, which in turn triggers DELLA protein ubiquitination and proteolysis via the SCFSLY1 E3 ubiquitin ligase and 26S proteasome. Although DELLA cannot be destroyed in the sleepy1-2 (sly1-2) F-box mutant, long dry after-ripening and GID1 overexpression can relieve the strong sly1-2 seed dormancy phenotype. It appears that sly1-2 seed dormancy results from abscisic acid (ABA) signaling downstream of DELLA, since dormant sly1-2 seeds accumulate high levels of ABA hormone and loss of ABA sensitivity rescues sly1-2 seed germination. DELLA positively regulates the expression of XERICO, an inducer of ABA biosynthesis. GID1b overexpression rescues sly1-2 germination through proteolysis-independent DELLA down-regulation associated with increased expression of GA-inducible genes and decreased ABA accumulation, apparently as a result of decreased XERICO messenger RNA levels. Higher levels of GID1 overexpression are associated with more efficient sly1 germination and increased GID1-GA-DELLA complex formation, suggesting that GID1 down-regulates DELLA through protein binding. After-ripening results in increased GA accumulation and GID1a-dependent GA signaling, suggesting that after-ripening triggers GA-stimulated GID1-GA-DELLA protein complex formation, which in turn blocks DELLA transcriptional activation of the XERICO inhibitor of seed germination. PMID:23818171

  17. Touch-induced changes in Arabidopsis morphology dependent on gibberellin breakdown.

    PubMed

    Lange, Maria João Pimenta; Lange, Theo

    2015-02-09

    Touch can lead to a reduction in plant growth and a delay in flowering time. Touch-induced changes in plant morphology, termed thigmomorphogenesis, have been shown to depend on the phytohormone jasmonate(1). However, touch-induced phenotypes are also reminiscent of plants deficient in the phytohormone gibberellin(2). Here we assess the effect of touch on wild-type Arabidopsis plants and mutants deficient in gibberellin signalling. We show that touch leads to stunted growth and delayed flowering in wild-type plants, as expected. These touch-induced changes in morphology are accompanied by a reduction in gibberellin levels, and can be reversed through the application of a bioactive form of gibberellin. We further show that touch induces the expression of AtGA2ox7, which encodes an enzyme involved in gibberellin catabolism. Arabidopsis ga2ox7 loss-of-function mutants do not respond to touch, suggesting that this gene is a key regulator of thigmomorphogenesis. We conclude that touch-induced changes in Arabidopsis morphology depend on gibberellin catabolism. Given that AtGA2ox7 helps to confer resistance to salt stress, and that touch can increase plant resistance to pathogens, we suggest that gibberellin catabolism could be targeted to improve plant resistance to abiotic and biotic stress.

  18. Active THz inspection of water content in plants

    NASA Astrophysics Data System (ADS)

    Etayo, D.; Iriarte, J. C.; Palacios, I.; Teniente, J.; Ederra, I.; Gonzalo, R.

    2010-04-01

    The THz range offers the possibility of measuring water content. This can be useful in wine industry to control plants water levels and also to decrease irrigation costs. This paper presents a THz imaging system used to characterise water content in leaves using frequency and time domain methods from 0.14 to 0.22 THz. Our results show the possibility of getting useful information out of the preformed measurements.

  19. Gibberellin mediates the development of gelatinous fibres in the tension wood of inclined Acacia mangium seedlings

    PubMed Central

    Nugroho, Widyanto Dwi; Nakaba, Satoshi; Yamagishi, Yusuke; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

    2013-01-01

    Background and Aims Gibberellin stimulates negative gravitropism and the formation of tension wood in tilted Acacia mangium seedlings, while inhibitors of gibberellin synthesis strongly inhibit the return to vertical growth and suppress the formation of tension wood. To characterize the role of gibberellin in tension wood formation and gravitropism, this study investigated the role of gibberellin in the development of gelatinous fibres and in the changes in anatomical characteristics of woody elements in Acacia mangium seedlings exposed to a gravitational stimulus. Methods Gibberellin, paclobutrazol and uniconazole-P were applied to the soil in which seedlings were growing, using distilled water as the control. Three days after the start of treatment, seedlings were inclined at 45 ° to the vertical and samples were harvested 2 months later. The effects of the treatments on wood fibres, vessel elements and ray parenchyma cells were analysed in tension wood in the upper part of inclined stems and in the opposite wood on the lower side of inclined stems. Key Results Application of paclobutrazol or uniconazole-P inhibited the increase in the thickness of gelatinous layers and prevented the elongation of gelatinous fibres in the tension wood of inclined stems. By contrast, gibberellin stimulated the elongation of these fibres. Application of gibberellin and inhibitors of gibberellin biosynthesis had only minor effects on the anatomical characteristics of vessel and ray parenchyma cells. Conclusions The results suggest that gibberellin is important for the development of gelatinous fibres in the tension wood of A. mangium seedlings and therefore in gravitropism. PMID:24043495

  20. Isolation of gibberellin precursors from heavily pigmented tissues.

    PubMed

    Metzger, J D; Hazebroek, J P

    1989-12-01

    The kauranoid precursors of gibberellins are difficult to isolate from heavily pigmented plant tissues. In this paper, we describe relatively simple and efficient procedures for the purification of these compounds from tissues containing chlorophyll and other high molecular weight pigments. Extracts of shoots from Thlaspi arvense L. were subjected first to size exclusion chromatography using ethyl acetate as the eluting solvent. This procedure resulted in the separation of kauranoids as a class of compounds from chlorophyll. Typically, a 90% reduction in mass of the kauranoid enriched-fraction was observed. This fraction was subjected to reverse phase high performance liquid chromatography and individual fractions analyzed by combined gas chromatography-mass spectrometry. Five kauranoids were identified in shoot extracts of T. arvense: ent-kaur-16-ene, ent-kaur-16-en-19-ol, ent-kaur-16-en-19-oic acid, trachylobanoic acid, and 7beta, 13-dihydroxykaurenolide. The metabolic relationships of these compounds to the gibberellins previously identified in this species (JD Metzger, MC Mardaus [1986] Plant Physiol 80: 396-402) are discussed. In addition, the utility of size exclusion chromatography in preparative situations is demonstrated by the purification of ent-kaurenoic acid in milligram quantities from the florets of Helianthus annuus L.

  1. A Tandem Array of ent-Kaurene Synthases in Maize with Roles in Gibberellin and More Specialized Metabolism1[OPEN

    PubMed Central

    Fu, Jingye; Lu, Xuan; Xu, Meimei; Wang, Qiang

    2016-01-01

    While most commonly associated with its role in gibberellin phytohormone biosynthesis, ent-kaurene also serves as an intermediate in more specialized diterpenoid metabolism, as exemplified by the more than 800 known derived natural products. Among these are the maize kauralexins. However, no ent-kaurene synthases (KSs) have been identified from maize. The maize gibberellin-deficient dwarf-5 (d5) mutant has been associated with a loss of KS activity. The relevant genetic lesion has been previously mapped, and was found here to correlate with the location of the KS-like gene ZmKSL3. Intriguingly, this forms part of a tandem array with two other terpene synthases (TPSs). Although one of these, ZmTPS1, has been previously reported to encode a sesquiterpene synthase, and both ZmTPS1 and that encoded by the third gene, ZmKSL5, have lost the N-terminal γ-domain prototypically associated with KS(L)s, all three genes fall within the KS(L) or TPS-e subfamily. Here it is reported that all three genes encode enzymes that are targeted to the plastid in planta, where diterpenoid biosynthesis is initiated, and which all readily catalyze the production of ent-kaurene. Consistent with the closer phylogenetic relationship of ZmKSL3 with previously identified KSs from cereals, only transcription of this gene is affected in d5 plants. On the other hand, the expression of all three of these genes is inducible, suggesting a role in more specialized metabolism, such as that of the kauralexins. Thus, these results clarify not only gibberellin phytohormone, but also diterpenoid phytoalexin biosynthesis in this important cereal crop plant. PMID:26620527

  2. A Tandem Array of ent-Kaurene Synthases in Maize with Roles in Gibberellin and More Specialized Metabolism.

    PubMed

    Fu, Jingye; Ren, Fei; Lu, Xuan; Mao, Hongjie; Xu, Meimei; Degenhardt, Jörg; Peters, Reuben J; Wang, Qiang

    2016-02-01

    While most commonly associated with its role in gibberellin phytohormone biosynthesis, ent-kaurene also serves as an intermediate in more specialized diterpenoid metabolism, as exemplified by the more than 800 known derived natural products. Among these are the maize kauralexins. However, no ent-kaurene synthases (KSs) have been identified from maize. The maize gibberellin-deficient dwarf-5 (d5) mutant has been associated with a loss of KS activity. The relevant genetic lesion has been previously mapped, and was found here to correlate with the location of the KS-like gene ZmKSL3. Intriguingly, this forms part of a tandem array with two other terpene synthases (TPSs). Although one of these, ZmTPS1, has been previously reported to encode a sesquiterpene synthase, and both ZmTPS1 and that encoded by the third gene, ZmKSL5, have lost the N-terminal γ-domain prototypically associated with KS(L)s, all three genes fall within the KS(L) or TPS-e subfamily. Here it is reported that all three genes encode enzymes that are targeted to the plastid in planta, where diterpenoid biosynthesis is initiated, and which all readily catalyze the production of ent-kaurene. Consistent with the closer phylogenetic relationship of ZmKSL3 with previously identified KSs from cereals, only transcription of this gene is affected in d5 plants. On the other hand, the expression of all three of these genes is inducible, suggesting a role in more specialized metabolism, such as that of the kauralexins. Thus, these results clarify not only gibberellin phytohormone, but also diterpenoid phytoalexin biosynthesis in this important cereal crop plant.

  3. Fruit Growth in Arabidopsis Occurs via DELLA-Dependent and DELLA-Independent Gibberellin Responses[W][OA

    PubMed Central

    Fuentes, Sara; Ljung, Karin; Sorefan, Karim; Alvey, Elizabeth; Harberd, Nicholas P.; Østergaard, Lars

    2012-01-01

    Fruit growth and development depend on highly coordinated hormonal activities. The phytohormone gibberellin (GA) promotes growth by inducing degradation of the growth-repressing DELLA proteins; however, the extent to which DELLA proteins contribute to GA-mediated gynoecium and fruit development remains to be clarified. Here, we provide an in-depth characterization of the role of DELLA proteins in Arabidopsis thaliana fruit growth. We show that DELLA proteins are key regulators of reproductive organ size and important for ensuring optimal fertilization. We demonstrate that the seedless fruit growth (parthenocarpy) observed in della mutants can be directly attributed to the constitutive activation of GA signaling. It has been known for >75 years that another hormone, auxin, can induce formation of seedless fruits. Using mutants with complete lack of DELLA activity, we show here that auxin-induced parthenocarpy occurs entirely through GA signaling in Arabidopsis. Finally, we uncover the existence of a DELLA-independent GA response that promotes fruit growth. This response requires GIBBERELLIN-INSENSITIVE DWARF1–mediated GA perception and a functional 26S proteasome and involves the basic helix-loop-helix protein SPATULA as a key component. Taken together, our results describe additional complexities in GA signaling during fruit development, which may be particularly important to optimize the conditions for successful reproduction. PMID:23064323

  4. The dwarf-1 (dt) Mutant of Zea mays blocks three steps in the gibberellin-biosynthetic pathway.

    PubMed

    Spray, C R; Kobayashi, M; Suzuki, Y; Phinney, B O; Gaskin, P; MacMillan, J

    1996-09-17

    In plants, gibberellin (GA)-responding mutants have been used as tools to identify the genes that control specific steps in the GA-biosynthetic pathway. They have also been used to determine which native GAs are active per se, i.e., further metabolism is not necessary for bioactivity. We present metabolic evidence that the D1 gene of maize (Zea mays L.) controls the three biosynthetic steps: GA20 to GA1, Ga20 to GA5, and GA5 to GA3. We also present evidence that three gibberellins, GA1, GA5, and GA3, have per se activity in stimulating shoot elongation in maize. The metabolic evidence comes from the injection of [17-13C,3H]GA20 and [17-13C,3H]GA5 into seedlings of d1 and controls (normal and d5), followed by isolation and identification of the 13C-labeled metabolites by full-scan GC-MS and Kovats retention index. For the controls, GA20 was metabolized to GA1,GA3, and GA5; GA5 was metabolized to GA3. For the d1 mutant, GA20 was not metabolized to GA1, GA3, or to GA5, and GA5 was not metabolized to GA3. The bioassay evidence is based on dosage response curves using d1 seedlings for assay. GA1, GA3, and GA5 had similar bioactivities, and they were 10-times more active than GA20.

  5. Nighttime Sugar Starvation Orchestrates Gibberellin Biosynthesis and Plant Growth in Arabidopsis[W

    PubMed Central

    Paparelli, Eleonora; Parlanti, Sandro; Gonzali, Silvia; Novi, Giacomo; Mariotti, Lorenzo; Ceccarelli, Nello; van Dongen, Joost T.; Kölling, Katharina; Zeeman, Samuel C.; Perata, Pierdomenico

    2013-01-01

    A plant’s eventual size depends on the integration of its genetic program with environmental cues, which vary on a daily basis. Both efficient carbon metabolism and the plant hormone gibberellin are required to guarantee optimal plant growth. Yet, little is known about the interplay between carbon metabolism and gibberellins that modulates plant growth. Here, we show that sugar starvation in Arabidopsis thaliana arising from inefficient starch metabolism at night strongly reduces the expression of ent-kaurene synthase, a key regulatory enzyme for gibberellin synthesis, the following day. Our results demonstrate that plants integrate the efficiency of photosynthesis over a period of days, which is transduced into a daily rate of gibberellin biosynthesis. This enables a plant to grow to a size that is compatible with its environment. PMID:24096343

  6. Antheridiogen determines sex in ferns via a spatiotemporally split gibberellin synthesis pathway.

    PubMed

    Tanaka, Junmu; Yano, Kenji; Aya, Koichiro; Hirano, Ko; Takehara, Sayaka; Koketsu, Eriko; Ordonio, Reynante Lacsamana; Park, Seung-Hyun; Nakajima, Masatoshi; Ueguchi-Tanaka, Miyako; Matsuoka, Makoto

    2014-10-24

    Some ferns possess the ability to control their sex ratio to maintain genetic variation in their colony with the aid of antheridiogen pheromones, antheridium (male organ)-inducing compounds that are related to gibberellin. We determined that ferns have evolved an antheridiogen-mediated communication system to produce males by modifying the gibberellin biosynthetic pathway, which is split between two individuals of different developmental stages in the colony. Antheridiogen acts as a bridge between them because it is more readily taken up by prothalli than bioactive gibberellin. The pathway initiates in early-maturing prothalli (gametophytes) within a colony, which produce antheridiogens and secrete them into the environment. After the secreted antheridiogen is absorbed by neighboring late-maturing prothalli, it is modified in to bioactive gibberellin to trigger male organ formation.

  7. Nighttime sugar starvation orchestrates gibberellin biosynthesis and plant growth in Arabidopsis.

    PubMed

    Paparelli, Eleonora; Parlanti, Sandro; Gonzali, Silvia; Novi, Giacomo; Mariotti, Lorenzo; Ceccarelli, Nello; van Dongen, Joost T; Kölling, Katharina; Zeeman, Samuel C; Perata, Pierdomenico

    2013-10-01

    A plant's eventual size depends on the integration of its genetic program with environmental cues, which vary on a daily basis. Both efficient carbon metabolism and the plant hormone gibberellin are required to guarantee optimal plant growth. Yet, little is known about the interplay between carbon metabolism and gibberellins that modulates plant growth. Here, we show that sugar starvation in Arabidopsis thaliana arising from inefficient starch metabolism at night strongly reduces the expression of ent-kaurene synthase, a key regulatory enzyme for gibberellin synthesis, the following day. Our results demonstrate that plants integrate the efficiency of photosynthesis over a period of days, which is transduced into a daily rate of gibberellin biosynthesis. This enables a plant to grow to a size that is compatible with its environment.

  8. The Message Content of Advertisements for Active Army Enlistments

    DTIC Science & Technology

    1988-05-01

    to last 15 minutes. Sample Size The youth interviewed during the message content analysis research represent a nonprobability , quota sample of young...men and women 16- to 24-years-old. This age range parallels that used in the 4. . ACOMS youth interview. Mall-intercept samples are inherently nonprob ...cations Objectives Measurement System (ACOMS) project. The results are based on a sample of 3,665 male and female 16- to 24-year-olds who viewed 13

  9. Environmental Print Activities for Teaching Mathematics and Content Areas.

    ERIC Educational Resources Information Center

    Rule, Audrey C., Ed.; McIntyre, Sandra, Ed.; Ranous, Meg, Ed.

    Twenty-three mathematics activities that use environmental print materials are presented, along with two activities that focus on music education, one that highlights history concepts, and five science activities. The environmental print materials are words and images cut from food or other product packaging and mounted on mat board cards.…

  10. Diversion of carbon flux from gibberellin to steviol biosynthesis by over-expressing SrKA13H induced dwarfism and abnormality in pollen germination and seed set behaviour of transgenic Arabidopsis.

    PubMed

    Guleria, Praveen; Masand, Shikha; Yadav, Sudesh Kumar

    2015-07-01

    This paper documents the engineering of Arabidopsis thaliana for the ectopic over-expression of SrKA13H (ent-kaurenoic acid-13 hydroxylase) cDNA from Stevia rebaudiana. HPLC analysis revealed the significant accumulation of steviol (1-3 μg g(-1) DW) in two independent transgenic Arabidopsis lines over-expressing SrKA13H compared with the control. Independent of the steviol concentrations detected, both transgenic lines showed similar reductions in endogenous bioactive gibberellins (GA1 and GA4). They possessed phenotypic similarity to gibberellin-deficient mutants. The reduction in endogenous gibberellin content was found to be responsible for dwarfism in the transgenics. The exogenous application of GA3 could rescue the transgenics from dwarfism. The hypocotyl, rosette area, and stem length were all considerably reduced in the transgenics. A noteworthy decrease in pollen viability was noticed and, similarly, a retardation of 60-80% in pollen germination rate was observed. The exogenous application of steviol (0.2, 0.5, and 1.0 μg ml(-1)) did not influence pollen germination efficiency. This has suggested that in planta formation of steviol was not responsible for the observed changes in transgenic Arabidopsis. Further, the seed yield of the transgenics was reduced by 24-48%. Hence, this study reports for the first time that over-expression of SrKA13H cDNA in Arabidopsis has diverted the gibberellin biosynthetic route towards steviol biosynthesis. The Arabidopsis transgenics showed a significant reduction in endogenous gibberellins that might be responsible for the dwarfism, and the abnormal behaviour of pollen germination and seed set. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  11. Gibberellins Are Involved in Nodulation of Sesbania rostrata1

    PubMed Central

    Lievens, Sam; Goormachtig, Sofie; Den Herder, Jeroen; Capoen, Ward; Mathis, René; Hedden, Peter; Holsters, Marcelle

    2005-01-01

    Upon submergence, Azorhizobium caulinodans infects the semiaquatic legume Sesbania rostrata via the intercellular crack entry process, resulting in lateral root-based nodules. A gene encoding a gibberellin (GA) 20-oxidase, SrGA20ox1, involved in GA biosynthesis, was transiently up-regulated during lateral root base nodulation. Two SrGA20ox1 expression patterns were identified, one related to intercellular infection and a second observed in nodule meristem descendants. The infection-related expression pattern depended on bacterially produced nodulation (Nod) factors. Pharmacological studies demonstrated that GAs were involved in infection pocket and infection thread formation, two Nod factor-dependent events that initiate lateral root base nodulation, and that they were also needed for nodule primordium development. Moreover, GAs inhibited the root hair curling process. These results show that GAs are Nod factor downstream signals for nodulation in hydroponic growth. PMID:16258018

  12. Gibberellin precursor is involved in spore germination in the moss Physcomitrella patens.

    PubMed

    Anterola, Aldwin; Shanle, Erin; Mansouri, Katayoun; Schuette, Scott; Renzaglia, Karen

    2009-03-01

    Gibberellins are ent-kaurene derived phytohormones that are involved in seed germination, stem elongation, and flower induction in seed plants, as well as in antheridia formation and spore germination in ferns. Although ubiquitous in vascular plants, the occurrence and potential function(s) of gibberellins in bryophytes have not yet been resolved. To determine the potential role of gibberellin and/or gibberellin-like compounds in mosses, the effect of AMO-1618 on spores of Physcomitrella patens (Hedw.) B.S.G. was tested. AMO-1618, which inhibited ent-kaurene and gibberellin biosynthesis in angiosperms, also inhibited the bifunctional copalyl diphosphate synthase (E.C. 5.5.1.13)/ent-kaurene synthase (E.C. 4.2.3.19) of P. patens. AMO-1618 also caused a decrease in spore germination rates of P. patens, and this inhibitory effect was less pronounced in the presence of ent-kaurene. These results suggest that ent-kaurene biosynthesis is required by P. patens spores to germinate, implying the presence of gibberellin-like phytohormones in mosses.

  13. Gibberellin secreting rhizobacterium, Pseudomonas putida H-2-3 modulates the hormonal and stress physiology of soybean to improve the plant growth under saline and drought conditions.

    PubMed

    Kang, Sang-Mo; Radhakrishnan, Ramalingam; Khan, Abdul Latif; Kim, Min-Ji; Park, Jae-Man; Kim, Bo-Ra; Shin, Dong-Hyun; Lee, In-Jung

    2014-11-01

    The physiological changes in tolerant soybean plants under salt and drought stress conditions with Pseudomonas putida H-2-3 were investigated. A bacterial isolate H-2-3 was isolated from soil and identified as Pseudomonas putida H-2-3 by 16S rDNA sequences. The treatment of P. putida H-2-3 significantly increased the length, fresh and dry weight of shoot and chlorophyll content in gibberellins (GAs) deficient mutant Waito-c rice seedlings over the control, it might be the presence of GA1, GA4, GA9 and GA20. The soybean plant growth was retarded in salt (120 mM sodium chloride) and drought (15% polyethylene glycol) stress conditions at 10 days treatments, while P. putida H-2-3 effectively enhanced the shoot length and fresh weight of plants suffered at salt and drought stress. The chlorophyll content was lower in abiotic stress conditions and bacterial inoculant P. putida H-2-3 mitigated the stress effects by an evidence of higher quantity of chlorophyll content in plants exposed to salt and drought. The stress hormonal analysis revealed that individual treatment of P. putida H-2-3, salt and drought significantly enhanced the abscisic acid and salicylic acid content than their control. P. putida H-2-3 applied to salt and drought stressed plants showed a lower level of abscisic acid and salicylic acid and a higher level of jasmonic acid content. Under stress condition induced by salt and drought in plants expressed higher level of total polyphenol, superoxide dismutase and radical scavenging activity and no significant changes in flavonoids. The bio-inoculant, P. putida H-2-3 modulated those antioxidants by declining superoxide dismutase, flavonoids and radical scavenging activity. P. putida H-2-3 induced tolerance against abiotic stress was confirmed by a reduction of Na content in abiotic stressed plants. The results suggest that P. putida H-2-3 application reprograms the chlorophyll, stress hormones and antioxidants expression in abiotic stress affected

  14. Anticancer Activity, Antioxidant Activity, and Phenolic and Flavonoids Content of Wild Tragopogon porrifolius Plant Extracts

    PubMed Central

    Rishmawi, Suzi; Ariqat, Sharehan H.; Khalid, Mahmoud F.; Warad, Ismail; Salah, Zaidoun

    2016-01-01

    Tragopogon porrifolius, commonly referred to as white salsify, is an edible herb used in folk medicine to treat cancer. Samples of Tragopogon porrifolius plant grown wild in Palestine were extracted with different solvents: water, 80% ethanol, and 100% ethanol. The extracts were analyzed for their total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity (AA). Four different antioxidant assays were used to evaluate AA of the extracts: two measures the reducing power of the extracts (ferric reducing antioxidant power (FRAP) and cupric reducing antioxidant power (CUPRAC)), while two other assays measure the scavenging ability of the extracts (2,2-azino-di-(3-ethylbenzothialozine-sulphonic acid (ABTS)) and 2,2-diphenyl-1-picrylhydrazyl (DPPH)). Anticancer activity of the plant extracts were also tested on HOS and KHOS osteosarcoma cell lines. The results revealed that the polarity of the extraction solvent affects the TPC, TFC, and AA. It was found that both TPC and AA are highest for plant extracted with 80% ethanol, followed by water, and finally with 100% ethanol. TFC however was the highest in the following order: 80% ethanol > 100% ethanol > water. The plant extracts showed anticancer activities against KHOS cancer cell lines; they reduced total cell count and induced cell death in a drastic manner. PMID:27999608

  15. Variation in Rubisco content and activity under variable climatic factors.

    PubMed

    Galmés, Jeroni; Aranjuelo, Iker; Medrano, Hipólito; Flexas, Jaume

    2013-11-01

    The main objective of the present review is to provide a compilation of published data of the effects of several climatic conditions on Rubisco, particularly its activity, state of activation, and concentration, and its influence on leaf gas exchange and photosynthesis. The environmental conditions analyzed include drought, salinity, heavy metals, growth temperature, and elevated [O3], [CO2], and ultraviolet-B irradiance. The results show conclusive evidence for a major negative effect on activity of Rubisco with increasing intensity of a range of abiotic stress factors. This decrease in the activity of Rubisco is associated with down-regulation of the activation state of the enzyme (e.g., by de-carbamylation and/or binding of inhibitory sugar phosphates) in response to drought or high temperature. On the contrary, the negative effects of low temperature, heavy metal stress (cadmium), ozone, and UV-B stress on Rubisco activity are associated with changes in the concentration of Rubisco. Notably, in response to all environmental factors, the regulation of in vivo CO2 assimilation rate was related to Rubisco in vitro parameters, either concentration and/or carboxylation, depending on the particular stress. The importance of the loss of Rubisco activity and its repercussion on plant photosynthesis are discussed in the context of climate change. It is suggested that decreased Rubisco activity will be a major effect induced by climate change, which will need to be considered in any prediction model on plant productivity in the near future.

  16. Morphological characteristics, anatomical structure, and gene expression: novel insights into gibberellin biosynthesis and perception during carrot growth and development

    PubMed Central

    Wang, Guang-Long; Xiong, Fei; Que, Feng; Xu, Zhi-Sheng; Wang, Feng; Xiong, Ai-Sheng

    2015-01-01

    Gibberellins (GAs) are considered potentially important regulators of cell elongation and expansion in plants. Carrot undergoes significant alteration in organ size during its growth and development. However, the molecular mechanisms underlying gibberellin accumulation and perception during carrot growth and development remain unclear. In this study, five stages of carrot growth and development were investigated using morphological and anatomical structural techniques. Gibberellin levels in leaf, petiole, and taproot tissues were also investigated for all five stages. Gibberellin levels in the roots initially increased and then decreased, but these levels were lower than those in the petioles and leaves. Genes involved in gibberellin biosynthesis and signaling were identified from the carrotDB, and their expression was analyzed. All of the genes were evidently responsive to carrot growth and development, and some of them showed tissue-specific expression. The results suggested that gibberellin level may play a vital role in carrot elongation and expansion. The relative transcription levels of gibberellin pathway-related genes may be the main cause of the different bioactive GAs levels, thus exerting influences on gibberellin perception and signals. Carrot growth and development may be regulated by modification of the genes involved in gibberellin biosynthesis, catabolism, and perception. PMID:26504574

  17. Morphological characteristics, anatomical structure, and gene expression: novel insights into gibberellin biosynthesis and perception during carrot growth and development.

    PubMed

    Wang, Guang-Long; Xiong, Fei; Que, Feng; Xu, Zhi-Sheng; Wang, Feng; Xiong, Ai-Sheng

    2015-01-01

    Gibberellins (GAs) are considered potentially important regulators of cell elongation and expansion in plants. Carrot undergoes significant alteration in organ size during its growth and development. However, the molecular mechanisms underlying gibberellin accumulation and perception during carrot growth and development remain unclear. In this study, five stages of carrot growth and development were investigated using morphological and anatomical structural techniques. Gibberellin levels in leaf, petiole, and taproot tissues were also investigated for all five stages. Gibberellin levels in the roots initially increased and then decreased, but these levels were lower than those in the petioles and leaves. Genes involved in gibberellin biosynthesis and signaling were identified from the carrotDB, and their expression was analyzed. All of the genes were evidently responsive to carrot growth and development, and some of them showed tissue-specific expression. The results suggested that gibberellin level may play a vital role in carrot elongation and expansion. The relative transcription levels of gibberellin pathway-related genes may be the main cause of the different bioactive GAs levels, thus exerting influences on gibberellin perception and signals. Carrot growth and development may be regulated by modification of the genes involved in gibberellin biosynthesis, catabolism, and perception.

  18. Peanut skins-fortified peanut butters: effect of processing on the phenolics content, fibre content and antioxidant activity.

    PubMed

    Ma, Yuanyuan; Kerr, William L; Swanson, Ruthann B; Hargrove, James L; Pegg, Ronald B

    2014-02-15

    Incorporation of ground peanut skins (PS) into peanut butter at 1.25%, 2.5%, 3.75%, and 5.0% (w/w) resulted in a marked concentration-dependent increase in both the total phenolics content (TPC) and antioxidant activity. Using dry-blanched PS to illustrate, the TPC increased by 86%, 357%, 533%, and 714%, respectively, compared to the peanut butter control devoid of PS; the total proanthocyanidins content (TPACs) rose by 633%, 1933%, 3500%, and 5033%, respectively. NP-HPLC detection confirmed that the increase in the phenolics content was attributed to the endogenous proanthocyanidins of the PS, which were characterised as dimers to nonamers by NP-HPLC/ESI-MS. FRAP values increased correspondingly by 62%, 387%, 747%, and 829%, while H-ORAC(FL) values grew by 53%, 247%, 382%, and 415%, respectively. The dietary fibre content of dry-blanched PS was ~55%, with 89-93% being insoluble fibre. Data revealed that PS addition enhances the antioxidant capacity of the peanut butter, permits a "good source of fibre" claim, and offers diversification in the market's product line.

  19. Mutagenic activity and heterocyclic amine content of the human diet

    SciTech Connect

    Knize, M.G.; Dolbeare, F.A.; Cunningham, P.L.; Felton, J.S.

    1993-01-15

    The mutagenic activity and the mass amount of heterocyclic amines responsible for the mutagenic activity have been measured in some cooked foods. Cooked meats are the predominant source of mutagenic activity in the diet with values ranging from 0 to 10,000 revertants per gram reported in the Ames/Salmonelia test with strain TA98. Several heterocyclic amines are present and have been quantified using solid-phase extraction followed by HPLC. Frying at higher temperatures and for longer times produces the greatest mutagenic response, and concomitantly, the largest amounts of heterocyclic amines. Most of the mutagenic activity in fried meat samples can be accounted for by MelQx, DiMelQx and IQ, although other heterocylic amines are present and PHIP mutagenic activity becomes significant at higher temperatures. Non-meat products such as baked breads can also form significant mutagenic activity, particularly when overcooked. Commercially prepared hamburgers made from meat substitutes such as tofu, wheat gluten or tempeh and fried at 210{degrees}C have up to 10% of the mutagenic activity of a fried beef patty cooked under the same conditions. When detected, amounts of heterocyclic amines in fried beef patties range from a total of 0.35 ng/g for commercial beef hamburgers to 142 ng/g for a beef patty cooked over a barbecue. Dietary intake is expected to have a large range, from less than one microgram per day to over 50 micrograms per day based on current knowledge of known heterocyclic amine chemicals and heterocyclic amine-containing foods.

  20. Mutagenic activity and heterocyclic amine content of heated foods

    SciTech Connect

    Knize, M.G.; Johansson, M.; Jones, A.L.; Blakley, M.; Felton, J.S.

    1994-12-31

    Cooked foods were extracted and analyzed for mutagenic activity and assayed for known heterocyclic amines (HAs) by the Ames/Salmonella test and HPLC, respectively. Fried meats contain HAs (predominantly PhIP, MeIQx, DiMeIQx, and A{alpha}C) that are potent promutagens in bacteria, mutagenic in cultured mammalian cells, and carcinogenic in rodents and in nonhuman primates. Meats contain levels ranging from undetectable (< 0.1 ppb) to 50 ppb of known HAs when fried at temperatures from 190 to 250{degrees}C. These identified compounds are responsible for ca 75% of the measured mutagenic activity in Salmonella strain TA98. Barbecued beef and chicken have up to several thousand TA98 revertants per gram (rev/g) of cooked meat, with only ca 30% of the mutagenic activity accounted for by known heterocyclic amines. Some heated nonmeat foods also contain potent mutagenic activity. Toasted breads, cereals and snack foods have 0 to 10 TA98 rev/g, but overtoasting yields up to 40 rev/g, wheat and gluten-containing products are associated with higher activity. Grain-based coffee-substitute powders and instant coffees have 190 to 380 rev/g in TA98, and 1100 to 4000 rev/g in strain YG1024. The identify of the compounds responsible for the mutagenic activity are unknown in these non-meat foods. Toasted grain-based foods probably contribute less than 10% of the total mutagenic activity of the diet, with meat products responsible for the reminder. The finding of varying amounts of known and unknown mutagens in some cooked foods may be responsible for the poorly understood variation in human cancer incidence worldwide.

  1. [Effect of water stress on content of active constituents in Erigeron breviscaps].

    PubMed

    Zhang, Ya'ni; Su, Wenhua; Zhang, Guangfei

    2009-05-01

    To study the effect of water stress on the content of scutellarin and caffeate in Erigeron breviscaps. Fv/Fm, N content, as well as the content of scutellarin and caffeate under three water grads were measured. Fv/Fm of the plant decreased significantly in 8% and 23% water treatment, that proved drought and waterlogging occurred. Under the two conditions, the contents of N were lower but the contents of active constituents were higher than those under 15% treatment. The results support the carbon-nutrient balance hypothesis and the "stress effect hypothesis" for the formation of geo-herbs.

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

    PubMed

    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.

  3. CANTHARELLUS CIBARIUS - CULINARY-MEDICINAL MUSHROOM CONTENT AND BIOLOGICAL ACTIVITY.

    PubMed

    Muszyńska, Bozena; Kała, Katarzyna; Firlej, Anna; Sułkowska-Ziaja, Katarzyna

    2016-01-01

    One of the most frequently harvested mushrooms in Polish forests is Yellow chanterelle (chanterelle) - Cantharellus cibarius Fr. from the Cantharellaceae family. Chanterelle is an ectomycorrhizal mushroom occurring in Poland. Chanterelle lives in symbiosis with pine, spruce, oak and hombeam. In cookery, chanterelle is appreciated because of the aroma, taste, firmness and crunchiness of its fruiting bodies. Wild edible mushrooms are widely consumed in Asia, Western Europe and Central America. Chanterelle contains a great number of carbohydrates and proteins and a low amount of fat. Actual review presents the main groups of physiologically active primary and secondary metabolites in the fruiting bodies of chanterelle such as indole and phenolic compounds, carbohydrates, fatty acids, proteins, free amino acids, sterols, carotenoids, enzymes, vitamins and elements with biological activity. The presence of these compounds and elements conditions the nutrient and therapeutic activity of chanterelle, e.g., immunomodulatory, anti-inflammatory, antioxidant, antiviral, antimicrobial and antigenotoxic properties.

  4. Health and Physical Activity Content Knowledge of Pima Children

    ERIC Educational Resources Information Center

    Brusseau, Timothy; Kulinna, Pamela H.; Cothran, Donetta J.

    2011-01-01

    This study grounded in constructivist theory and the public health literature investigated Native American children's knowledge related to physical activity and healthy behavior concepts. Learning tends to be more meaningful and relevant when teachers take into consideration the students' knowledge and experiences. Therefore it is important to…

  5. Critique in Academic Disciplines and Active Learning of Academic Content

    ERIC Educational Resources Information Center

    Ford, Michael J.

    2010-01-01

    This article argues for increased theoretical specificity in the active learning process. Whereas constructivist learning emphasizes construction of meaning, the process articulated here complements meaning construction with disciplinary critique. This process is an implication of how disciplinary communities generate new knowledge claims, which…

  6. Learning Through Movement: Teaching Cognitive Content through Physical Activities.

    ERIC Educational Resources Information Center

    Werner, Peter H.; Burton, Elsie C.

    Action-oriented learning activities are focused on in this book which attempts to outline an approach for stimulating and motivating children to learn through movement. The book is divided into five parts, each dealing with an aspect of the elementary school curriculum. Part one is concerned with the language arts and is divided into three…

  7. Critique in Academic Disciplines and Active Learning of Academic Content

    ERIC Educational Resources Information Center

    Ford, Michael J.

    2010-01-01

    This article argues for increased theoretical specificity in the active learning process. Whereas constructivist learning emphasizes construction of meaning, the process articulated here complements meaning construction with disciplinary critique. This process is an implication of how disciplinary communities generate new knowledge claims, which…

  8. Health and Physical Activity Content Knowledge of Pima Children

    ERIC Educational Resources Information Center

    Brusseau, Timothy; Kulinna, Pamela H.; Cothran, Donetta J.

    2011-01-01

    This study grounded in constructivist theory and the public health literature investigated Native American children's knowledge related to physical activity and healthy behavior concepts. Learning tends to be more meaningful and relevant when teachers take into consideration the students' knowledge and experiences. Therefore it is important to…

  9. DELLA-mediated gibberellin signalling regulates Nod factor signalling and rhizobial infection

    PubMed Central

    Fonouni-Farde, Camille; Tan, Sovanna; Baudin, Maël; Brault, Mathias; Wen, Jiangqi; Mysore, Kirankumar S.; Niebel, Andreas; Frugier, Florian; Diet, Anouck

    2016-01-01

    Legumes develop symbiotic interactions with rhizobial bacteria to form nitrogen-fixing nodules. Bacterial Nod factors (NFs) and plant regulatory pathways modulating NF signalling control rhizobial infections and nodulation efficiency. Here we show that gibberellin (GA) signalling mediated by DELLA proteins inhibits rhizobial infections and controls the NF induction of the infection marker ENOD11 in Medicago truncatula. Ectopic expression of a constitutively active DELLA protein in the epidermis is sufficient to promote ENOD11 expression in the absence of symbiotic signals. We show using heterologous systems that DELLA proteins can interact with the nodulation signalling pathway 2 (NSP2) and nuclear factor-YA1 (NF-YA1) transcription factors that are essential for the activation of NF responses. Furthermore, MtDELLA1 can bind the ERN1 (ERF required for nodulation 1) promoter and positively transactivate its expression. Overall, we propose that GA-dependent action of DELLA proteins may directly regulate the NSP1/NSP2 and NF-YA1 activation of ERN1 transcription to regulate rhizobial infections. PMID:27586842

  10. Uncovering DELLA-Independent Gibberellin Responses by Characterizing New Tomato procera Mutants.

    PubMed

    Livne, Sivan; Lor, Vai S; Nir, Ido; Eliaz, Natanella; Aharoni, Asaph; Olszewski, Neil E; Eshed, Yuval; Weiss, David

    2015-06-01

    Gibberellin (GA) regulates plant development primarily by triggering the degradation/deactivation of the DELLA proteins. However, it remains unclear whether all GA responses are regulated by DELLAs. Tomato (Solanum lycopersicum) has a single DELLA gene named PROCERA (PRO), and its recessive pro allele exhibits constitutive GA activity but retains responsiveness to external GA. In the loss-of-function mutant pro(ΔGRAS), all examined GA developmental responses were considerably enhanced relative to pro and a defect in seed desiccation tolerance was uncovered. As pro, but not pro(ΔGRAS), elongation was promoted by GA treatment, pro may retain residual DELLA activity. In agreement with homeostatic feedback regulation of the GA biosynthetic pathway, we found that GA20oxidase1 expression was suppressed in pro(ΔGRAS) and was not affected by exogenous GA3. In contrast, expression of GA2oxidase4 was not affected by the elevated GA signaling in pro(ΔGRAS) but was strongly induced by exogenous GA3. Since a similar response was found in Arabidopsis thaliana plants with impaired activity of all five DELLA genes, we suggest that homeostatic GA responses are regulated by both DELLA-dependent and -independent pathways. Transcriptome analysis of GA-treated pro(ΔGRAS) leaves suggests that 5% of all GA-regulated genes in tomato are DELLA independent.

  11. An Investigation into Techniques for the Determination of Moisture Content on Activated Carbon

    DTIC Science & Technology

    1991-09-01

    Activated carbon (or charcoal ) is a universal adsorbent for the removal of a variety of organic/inorganic contaminants, in both gaseous and aqueous phase...AD-A245 938 i * *~fl Nadoni Waren AN INVESTIGATION INTO TECHNIQUES FOR THE DETERMNATION OF MOISTURE CONTENT ON ACTIVATED CARBON (U) by L.E. Cameron...INVESTIGATION INTO TECHNIQUES FOR THE DETERMINATION OF MOISTURE CONTENT ON ACTIVATED CARBON (U) by L.E. Cameron and S.H.C. Liang Chemical Protecti

  12. Flavanol content and antioxidant activity in winery byproducts.

    PubMed

    González-Paramás, Ana M; Esteban-Ruano, Sara; Santos-Buelga, Celestino; de Pascual-Teresa, Sonia; Rivas-Gonzalo, Julián C

    2004-01-28

    Proanthocyanidins, particularly those coming from wine and grape products, have became of interest to nutritionists. Particular attention is currently being paid to the exploitation of this kind of grape byproducts for obtaining bio-active phenolic compounds with potential application as food antioxidants and preventive agents against cancer and other diseases. In this work, the flavanol composition of various winery byproducts submitted to different degrees of industrial exploitation has been studied and their antioxidant activity determined using two different methods (TBARS and TEAC) to evaluate their interest as suitable sources for the preparation of flavanol-rich antioxidant extracts. All the byproducts studied were still good flavanol sources no matter their exploitation degree. An important conclusion was that dried grape seeds, obtained as an end byproduct after the color extraction and alcohol distillation of the wine pomace, still kept important flavanol concentrations and significant antioxidant activity, even if they were submitted to high temperatures. These byproducts can be considered a cheap source for the extraction of antioxidant flavanols, which can be used as dietary supplements or in the production of phytochemicals.

  13. Spatial structure of connection between the troposphere heat content and variations in solar and geomagnetic activities

    NASA Astrophysics Data System (ADS)

    Vasil'eva, L. A.; Molodykh, S. I.; Kovalenko, V. A.

    2016-03-01

    We have carried out correlation analysis of connection between the heat content of different tropospheric layers and variations of solar (F10.7cm) and geomagnetic activity (AA index) in 1950-2007. The heat content response to effects of solar and geomagnetic activity has been found to have an explicit spatial structure. The heat content of the most of the troposphere correlates with solar and geomagnetic activity; however, we have observed significant anticorrelation in some regions. The degree of connection between the tropospheric heat content change and variations of solar and geomagnetic activity have been shown to depend on the time scale (time averaging period). The time averaging period increasing from 5 to 7 years, the correlation coefficient grows in most regions (up to 0.6-0.7), but if the increase continues, only weaker growth is observed. This time-scale dependence can be explained by the fact that the majority of variations in tropospheric heat content on the time-scale of less than 5 years are affected by processes having no connection with solar or geomagnetic activity. We have performed analysis of the influence of atmospheric circulation on connection between the tropospheric heat content change and variations of solar and geomagnetic activity. The heat content change in regions that are frequently occupied by the cyclones is shown to have practically no connection with variations of solar and geomagnetic activity.

  14. Active content determination of pharmaceutical tablets using near infrared spectroscopy as Process Analytical Technology tool.

    PubMed

    Chavez, Pierre-François; Sacré, Pierre-Yves; De Bleye, Charlotte; Netchacovitch, Lauranne; Mantanus, Jérôme; Motte, Henri; Schubert, Martin; Hubert, Philippe; Ziemons, Eric

    2015-11-01

    The aim of this study was to develop Near infrared (NIR) methods to determine the active content of non-coated pharmaceutical tablets manufactured from a proportional tablet formulation. These NIR methods intend to be used for the monitoring of the active content of tablets during the tableting process. Firstly, methods were developed in transmission and reflection modes to quantify the API content of the lowest dosage strength. Secondly, these methods were fully validated for a concentration range of 70-130% of the target active content using the accuracy profile approach based on β-expectation tolerance intervals. The model using the transmission mode showed a better ability to predict the right active content compared to the reflection one. However, the ability of the reflection mode to quantify the API content in the highest dosage strength was assessed. Furthermore, the NIR method based on the transmission mode was successfully used to monitor at-line the tablet active content during the tableting process, providing better insight of the API content during the process. This improvement of control of the product quality provided by this PAT method is thoroughly compliant with the Quality by Design (QbD) concept. Finally, the transfer of the transmission model from the off-line to an on-line spectrometer was efficiently investigated.

  15. Content and activity of cAMP response element-binding protein regulate platelet-derived growth factor receptor-alpha content in vascular smooth muscles.

    PubMed

    Watson, Peter A; Vinson, Charles; Nesterova, Albina; Reusch, Jane E-B

    2002-08-01

    Experiments in vascular smooth muscle cells (SMCs) indicate that the transcription factor cAMP response element-binding protein (CREB), the cyclic nucleotide response element-binding protein, suppresses expression of the platelet-derived growth factor-alpha receptor gene (PDGFRalpha). Adenovirus-mediated expression of constitutively active CREB mutants decreases PDGFRalpha mRNA, PDGFRalpha protein, and PDGFRalpha promoter-luciferase reporter activity in cultured SMCs. Expression of dominant negative CREB protein, A-CREB, increases PDGFRalpha protein content and the PDGFRalpha-promoter activity in SMCs. Active CREB prevents activation of PDGFRalpha promoter-luciferase reporter activity by CCAAT/enhancer-binding protein-delta (C/EBPdelta), shown to mediate IL-1beta stimulation of PDGFRalpha expression. Exposure of cultured SMCs to high glucose or reactive oxidant stress, which decrease CREB protein content and activity, increases PDGFRalpha protein content and promoter activity. Expression of active CREB blunts reactive oxidant stress-induced PDGFRalpha accumulation in SMCs. Loss of CREB protein in aortic walls of rats with streptozotocin-induced diabetes is accompanied by an increase in PDGFRalpha content. In Ob/Ob mice (which demonstrate reduced aortic wall CREB content vs. Ob/- controls), treatment with the peroxisomal proliferator-activated receptor gamma rosiglitazone increases CREB content and decreases PDGFRalpha content in the aortic wall. Thus, both in vitro and in vivo loss of CREB content and activity and subsequent accumulation of PDGFRalpha may contribute to SMC activation during diabetes.

  16. Phenolic content and antioxidant activities of burr parsley (Caucalis platycarpos L.).

    PubMed

    Plazonić, Ana; Mornar, Ana; Maleš, Željan; Kujundžić, Nikola

    2013-07-22

    Since C. platycarpos contains a wide variety of antioxidants, in the present study total flavonoid and phenolic acid content as well as antioxidative activity of various C. platycarpos extracts were investigated. The results obtained show a significant polyphenol content and antioxidant activity of the investigated plant. Moreover, a positive correlation between antioxidant activity and content of flavonoids and phenolic acids was found, indicating the responsibility of these compounds for the antioxidant effectiveness of C. platycarpos extracts and making C. platycarpos a good potential source of natural antioxidants.

  17. Gibberellins Promote Trichome Formation by Up-Regulating GLABROUS1 in Arabidopsis1

    PubMed Central

    Perazza, Daniel; Vachon, Gilles; Herzog, Michel

    1998-01-01

    Trichome development is dependent on gibberellin (GA) signaling in Arabidopsis thaliana. Using the GA-deficient mutant ga1–3, the GA-response mutant spy-5, and uniconazol (a GA-biosynthesis inhibitor), we show that the GA level response correlates positively with both trichome number and trichome branch number. Two genes, GL1 and TTG, are required for trichome initiation. In ga1–3, coexpression of GL1 and R, the maize TTG functional homolog, under control of the constitutive 35S promoter, restored trichome development, whereas overexpression of neither GL1 nor R alone was sufficient to significantly suppress the glabrous phenotype. We next focused on GL1 regulation by GAs. In the double mutant the gl1–1 glabrous phenotype is epistatic to the spy-5 phenotype, suggesting that GL1 acts downstream of the GA signal transduction pathway. The activity of a β-glucuronidase reporter gene driven by the GL1 promoter was decreased in the wild type grown on uniconazol and showed a clear GA-dependent activation in ga1–3. Finally, quantification of GL1 transcript levels by reverse transcriptase-polymerase chain reaction demonstrated that relative to wild type, ga1–3 plants contained less transcript. These data support the hypothesis that GAs induce trichome development through up-regulation of GL1 and possibly TTG genes. PMID:9625690

  18. Floral homeotic genes are targets of gibberellin signaling in flower development.

    PubMed

    Yu, Hao; Ito, Toshiro; Zhao, Yuanxiang; Peng, Jinrong; Kumar, Prakash; Meyerowitz, Elliot M

    2004-05-18

    Gibberellins (GAs) are a class of plant hormones involved in the regulation of flower development in Arabidopsis. The GA-deficient ga1-3 mutant shows retarded growth of all floral organs, especially abortive stamen development that results in complete male sterility. Until now, it has not been clear how GA regulates the late-stage development of floral organs after the establishment of their identities within floral meristems. Various combinations of null mutations of DELLA proteins can gradually rescue floral defects in ga1-3. In particular, the synergistic effect of rga-t2 and rgl2-1 can substantially restore flower development in ga1-3. We find that the transcript levels of floral homeotic genes APETALA3 (AP3), PISTILLATA (PI), and AGAMOUS (AG) are immediately upregulated in young flowers of ga1-3 upon GA treatment. Using a steroid-inducible activation of RGA, we further demonstrated that these floral homeotic genes are transcriptionally repressed by RGA activity in young flowers whereas the expression of LEAFY (LFY) and APETALA1 (AP1) is not substantially affected. In addition, we observed the partial rescue of floral defects in ga1-3 by overexpression of AG. Our results indicate that GA promotes the expression of floral homeotic genes by antagonizing the effects of DELLA proteins, thereby allowing continued flower development.

  19. Gibberellins Regulate Ovule Integument Development by Interfering with the Transcription Factor ATS1[OPEN

    PubMed Central

    Sacristan, Raquel

    2016-01-01

    Gibberellins (GAs) are plant hormones that regulate most plant life cycle aspects, including flowering and fruit development. Here, we demonstrate the implication of GAs in ovule development. DELLA proteins, negative GA response regulators, act as positive factors for ovule integument development in a mechanism that involves transcription factor ABERRANT TESTA SHAPE (ATS). The seeds of the della global mutant, a complete loss-of-function of DELLA, and the ats-1 mutant are remarkably similar, with a round shape, a disorganized testa, and viviparism. These defects are the result of an alteration in integuments that fail to fully develop and are shorter than in wild-type plants. ats-1 also shows some GA-related phenotypes, for example, higher germination rates and early flowering. In fact, ats-1 has elevated GA levels due to the activation of GA biosynthesis genes, which indicates that ATS inhibits GA biosynthesis. Moreover, DELLAs and ATS proteins interact, which suggests the formation of a transcriptional complex that regulates the expression of genes involved in integument growth. Therefore, the repression of GA biosynthesis by ATS would result in the stabilization of DELLAs to ensure correct ATS-DELLA complex formation. The requirement of both activities to coordinate proper ovule development strongly argues that the ATS-DELLA complex acts as a key molecular factor. This work provides the first evidence for a role of GAs in ovule and seed development. PMID:27794102

  20. Effects of gibberellins on seed germination of phytochrome-deficient mutants of Arabidopsis thaliana.

    PubMed

    Yang, Y Y; Nagatani, A; Zhao, Y J; Kang, B J; Kendrick, R E; Kamiya, Y

    1995-10-01

    Experiments were carried out to explore the involvement of gibberellins (GAs) in the light-induced germination of Arabidopsis thaliana (L.) Heynh, using wild type (WT) and phytochrome-deficient mutants (phyA, phyB and phyAphyB deficient in phytochrome A, B and A plus B, respectively). Seed germination of WT and phytochrome-deficient mutants was inhibited by uniconazole (an inhibitor of an early step in biosynthesis of GA, the oxidation of ent-kaurene) and prohexadione (an inhibitor of late steps, namely, 2 beta- and 3 beta-hydroxylation). This inhibition was overcome by simultaneous application of 10(-5) M GA4. The relative activity of GAs for promoting germination of uniconazole-treated seeds was GA4 > GA1 = GA9 > GA20. The wild type and the phyA and phyB mutants had an increased response to a red light pulse in the presence of GA1, GA4, GA9, GA20 and GA24 but there were no significant differences in activity of each GA between the mutants. Therefore, neither phytochrome A nor hytochrome B appears to regulate GA biosynthesis from GA12 to GA4 during seed germination, since the conversion of GA12 to GA9 is regulated by one enzyme (GA 20-oxidase). However, GA responsiveness appears to be regulated by phytochromes other than phytochromes A and B, since the phyAphyB double mutant retains the photoreversible increased response to GAs after a red light pulse.

  1. The GA2 locus of Arabidopsis thaliana encodes ent-kaurene synthase of gibberellin biosynthesis.

    PubMed

    Yamaguchi, S; Sun, T p; Kawaide, H; Kamiya, Y

    1998-04-01

    The ga2 mutant of Arabidopsis thaliana is a gibberellin-deficient dwarf. Previous biochemical studies have suggested that the ga2 mutant is impaired in the conversion of copalyl diphosphate to ent-kaurene, which is catalyzed by ent-kaurene synthase (KS). Overexpression of the previously isolated KS cDNA from pumpkin (Cucurbita maxima) (CmKS) in the ga2 mutant was able to complement the mutant phenotype. A genomic clone coding for KS, AtKS, was isolated from A. thaliana using CmKS cDNA as a heterologous probe. The corresponding A. thaliana cDNA was isolated and expressed in Escherichia coli as a fusion protein. The fusion protein showed enzymatic activity that converted [3H]copalyl diphosphate to [3H]ent-kaurene. The recombinant AtKS protein derived from the ga2-1 mutant is truncated by 14 kD at the C-terminal end and does not contain significant KS activity in vitro. Sequence analysis revealed that a C-2099 to T base substitution, which converts Gln-678 codon to a stop codon, is present in the AtKS cDNA from the ga2-1 mutant. Taken together, our results show that the GA2 locus encodes KS.

  2. Antioxidant activity and polyphenol content in cultivated and wild edible fruits grown in Panama

    PubMed Central

    Murillo, Enrique; Britton, Gabrielle B.; Durant, Armando A.

    2012-01-01

    Objectives: The present research was undertaken to determine the antioxidant activity and total polyphenol content of cultivated and wild edible fruits consumed in Panama. Materials and Methods: 39 cultivated and wild edible fruits antioxidant activity and total polyphenol content was assessed by using the DPPH and the Folin-Ciocalteu assays, respectively. Results and Discussion: The antioxidant composition of the fruits varied between 1083.33 and 16.22 mg TEAC/100 g fresh weight. On the other hand, the total phenolic content of the 39 fruits tested ranged from 604.80 to 35.10 mg GAE/100 g FW. Ziziphus mauritania presented the highest antioxidant activity and the largest phenolic content, whereas most fruits had a moderate TEAC value. Conclusion: Fruits polyphenol content was strongly correlated with antioxidant properties, which pointed out the important role of these compounds in the prevention of many types of cancer, neurological ailments, and cardiovascular diseases through diverse antioxidant mechanisms. PMID:23248565

  3. Breadfruit (Artocarpus altilis) gibberellin 2-oxidase genes in stem elongation and abiotic stress response.

    PubMed

    Zhou, Yuchan; Underhill, Steven J R

    2016-01-01

    Breadfruit (Artocarpus altilis) is a traditional staple tree crop in the Oceania. Susceptibility to windstorm damage is a primary constraint on breadfruit cultivation. Significant tree loss due to intense tropical windstorm in the past decades has driven a widespread interest in developing breadfruit with dwarf stature. Gibberellin (GA) is one of the most important determinants of plant height. GA 2-oxidase is a key enzyme regulating the flux of GA through deactivating biologically active GAs in plants. As a first step toward understanding the molecular mechanism of growth regulation in the species, we isolated a cohort of four full-length GA2-oxidase cDNAs, AaGA2ox1- AaGA2ox4 from breadfruit. Sequence analysis indicated the deduced proteins encoded by these AaGA2oxs clustered together under the C19 GA2ox group. Transcripts of AaGA2ox1, AaGA2ox2 and AaGA2ox3 were detected in all plant organs, but exhibited highest level in source leaves and stems. In contrast, transcript of AaGA2ox4 was predominantly expressed in roots and flowers, and displayed very low expression in leaves and stems. AaGA2ox1, AaGA2ox2 and AaGA2ox3, but not AaGA2ox4 were subjected to GA feedback regulation where application of exogenous GA3 or gibberellin biosynthesis inhibitor, paclobutrazol was shown to manipulate the first internode elongation of breadfruit. Treatments of drought or high salinity increased the expression of AaGA2ox1, AaGA2ox2 and AaGA2ox4. But AaGA2ox3 was down-regulated under salt stress. The function of AaGA2oxs is discussed with particular reference to their role in stem elongation and involvement in abiotic stress response in breadfruit. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  4. Protoporphyrin IX Content Correlates with Activity of Photobleaching Herbicides

    PubMed Central

    Becerril, Jose M.; Duke, Stephen O.

    1989-01-01

    Several laboratories have demonstrated recently that photobleaching herbicides such as acifluorfen and oxadiazon cause accumulation of protoporphyrin IX (PPIX), a photodynamic pigment capable of herbicidal activity. We investigated, in acifluorfen-treated tissues, the in vivo stability of PPIX, the kinetics of accumulation, and the correlation between concentration of PPIX and herbicidal damage. During a 20 hour dark period, PPIX levels rose from barely detectable concentrations to 1 to 2 nanomoles per 50 cucumber (Cucumis sativus L.) cotyledon discs treated with 10 micromolar acifluorfen. When placed in 500 micromoles per square meter per second PAR, PPIX levels decayed logarithmically, with an initial half-life of about 2.5 hours. PPIX levels at each time after exposure to light correlated positively with the cellular damage that occurred during the following 1 hour in both green and yellow (tentoxin-treated) cucumber cotyledon tissues. PPIX levels in discs incubated for 20 hours in darkness correlated positively with the acifluorfen concentration in which they were incubated. In cucumber, the level of herbicidal damage caused by several p-nitrodiphenyl other herbicides, a p-chlorodiphenylether herbicide, and oxadiazon correlated positively with the amount of PPIX induced to accumulate by each of the herbicide treatments. Similar results were obtained with acifluorfen-treated pigweed and velvetleaf primary leaf tissues. In cucumber, PPIX levels increased within 15 and 30 minutes after exposure of discs to 10 micromolar acifluorfen in the dark and light, respectively. These data strengthen the view that PPIX is responsible for all or a major part of the photobleaching activity of acifluorfen and related herbicides. PMID:16666869

  5. [Content and distribution of active components in cultivated and wild Taxus chinensis var. mairei plants].

    PubMed

    Yu, Shao-Shuai; Sun, Qi-Wu; Zhang, Xiao-Ping; Tian, Sheng-Ni; Bo, Pei-Lei

    2012-10-01

    Taxus chinensis var. mairei is an endemic and endangered plant species in China. The resources of T. chinensis var. mairei have been excessively exploited due to its anti-cancer potential, accordingly, the extant T. chinensis var. mairei population is decreasing. In this paper, ultrasonic extraction and HPLC were adopted to determine the contents of active components paclitaxel, 7-xylosyltaxol and cephalomannine in cultivated and wild T. chinensis var. mairei plants, with the content distribution of these components in different parts of the plants having grown for different years and at different slope aspects investigated. There existed obvious differences in the contents of these active components between cultivated and wild T. chinensis var. mairei plants. The paclitaxel content in the wild plants was about 0.78 times more than that in the cultivated plants, whereas the 7-xylosyltaxol and cephalomannine contents were slishtly higher in the cultivated plants. The differences in the three active components contents between different parts and tree canopies of the plants were notable, being higher in barks and upper tree canopies. Four-year old plants had comparatively higher contents of paclitaxel, 7-xylosyltaxol and cephalomannine (0.08, 0.91 and 0.32 mg x g(-1), respectively), and the plants growing at sunny slope had higher contents of the three active components, with significant differences in the paclitaxel and 7-xylosyltaxol contents and unapparent difference in the cephalomannine content of the plants at shady slope. It was suggested that the accumulation of the three active components in T. chinensis var. mairei plants were closely related to the sunshine conditions. To appropriately increase the sunshine during the artificial cultivation of T. chinensis var. mairei would be beneficial to the accumulation of the three active components in T. chinensis var. mairei plants.

  6. A National Study of Training Content and Activities for Faculty Development for Online Teaching

    ERIC Educational Resources Information Center

    Meyer, Katrina A.; Murrell, Vicki S.

    2014-01-01

    This article presents the results of a national study of 39 higher education institutions that collected information about their practices for faculty development for online teaching and particularly the content and training activities used during 2011-2012. This study found that the most frequently offered training content (97% of the…

  7. Contents of phenolics and flavonoids and antioxidant activities in skin, pulp, and seeds of miracle fruit

    USDA-ARS?s Scientific Manuscript database

    Miracle Fruit (Synsepalum dulificum) has been studied because of its unique taste modifying properties. This study investigated antioxidant activities, phenolic contents, and flavonoids in skin, pulp, and seeds of Miracle Fruit. The free phenolic content in skin was almost three times of that in p...

  8. Determining water content in activated carbon for double-layer capacitor electrodes

    NASA Astrophysics Data System (ADS)

    Egashira, Minato; Izumi, Takuma; Yoshimoto, Nobuko; Morita, Masayuki

    2016-09-01

    Karl-Fisher titration is used to estimate water contents in activated carbon and the distribution of impurity-level water in an activated carbon-solvent system. Normalization of the water content of activated carbon is attempted using vacuum drying after immersion in water was controlled. Although vacuum drying at 473 K and 24 h can remove large amounts of water, a substantial amount of water remains in the activated carbon. The water release to propylene carbonate is less than that to acetonitrile. The degradation of capacitor cell capacitance for activated carbon with some amount of water differs according to the electrolyte solvent type: acetonitrile promotes greater degradation than propylene carbonate does.

  9. Functional analysis of synthetic DELLA domain peptides and bioactive gibberellin assay using surface plasmon resonance technology.

    PubMed

    Zhao, Zhuoya; Xing, Zenan; Zhou, Min; Chen, Yi; Li, Chenzhong; Wang, Ruozhong; Xu, Wenzhong; Ma, Mi

    2015-11-01

    DELLA proteins and phytohormone gibberellin act together to control convergence point of plant development. A gibberellin-bound nuclear receptor that interacts with the N-terminal domain of DELLA proteins is required for gibberellin induced degradation of DELLA proteins. N-terminal DELLA domain includes two conserved motifs: DELLA and VHYNP. However, their respective functions remain unclear. Meanwhile, the identification and detection of several bioactive gibberellins from the more than 100 gibberellin metabolites are overwhelmingly difficult for their similar structures. Using in vitro biochemical approach, our work demonstrates for the first time that the synthetic GAI N-terminal DELLA domain peptides have similar bioactive function as the expressed protein to interact with AtGID1a receptor. Furthermore, our results reveal that DELLA motif is vitally important region and DELLA segment is essentially required region to recognize AtGID1a receptor. Finally, based on bioactive GA-dependent of the interaction between AtGID1a and DELLA protein, we generated a new method that could identify and detect bioactive GAs accurately and rapidly with surface plasmon resonance assays. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Differences in phytase activity and phytic acid content between cultivated and Tibetan annual wild barleys.

    PubMed

    Dai, Fei; Qiu, Long; Xu, Yang; Cai, Shengguan; Qiu, Boyin; Zhang, Guoping

    2010-11-24

    The Qinghai-Tibetan Plateau in China is considered to be one of the original centers of cultivated barley. At present, little is known about the phytase activity (Phy) or phytic acid content (PA) in grains of Tibetan annual wild barley. Phy and PA were determined in grains of 135 wild and 72 cultivated barleys. Phy ranged from 171.3 to 1299.2 U kg(-1) and from 219.9 to 998.2 U kg(-1) for wild and cultivated barleys, respectively. PA and protein contents were much higher in wild barley than in cultivated barley. Tibetan annual wild barley showed a larger genetic diversity in phytase activity and phytic acid and protein contents and is of value for barley breeding. There is no significant correlation between phytase activity and phytic acid or protein content in barley grains, indicating that endogenous phytase activity had little effect on the accumulation of phytic acid.

  11. The Effect of Physical Activity on Science Competence and Attitude towards Science Content

    ERIC Educational Resources Information Center

    Klinkenborg, Ann Maria

    2011-01-01

    This study examines the effect of physical activity on science instruction. To combat the implications of physical inactivity, schools need to be willing to consider all possible opportunities for students to engage in moderate-to-vigorous physical activity (MVPA). Integrating physical activity with traditional classroom content is one…

  12. The Effect of Physical Activity on Science Competence and Attitude towards Science Content

    ERIC Educational Resources Information Center

    Klinkenborg, Ann Maria

    2011-01-01

    This study examines the effect of physical activity on science instruction. To combat the implications of physical inactivity, schools need to be willing to consider all possible opportunities for students to engage in moderate-to-vigorous physical activity (MVPA). Integrating physical activity with traditional classroom content is one…

  13. Regulation of Gibberellin 20-Oxidase and Gibberellin 3β-Hydroxylase Transcript Accumulation during De-Etiolation of Pea Seedlings1

    PubMed Central

    Ait-Ali, Tahar; Frances, Shannon; Weller, James L.; Reid, James B.; Kendrick, Richard E.; Kamiya, Yuji

    1999-01-01

    Gibberellin (GA) 20-oxidase (GA 20-ox) and GA 3β-hydroxylase (GA 3β-hy) are enzymes that catalyze the late steps in the formation of active GAs, and are potential control points in the regulation of GA biosynthesis by light. We have investigated the photoregulation of the GA 20-ox and GA 3β-hy transcript levels in pea (Pisum sativum L.). The GA 20-ox transcript level was higher in light-grown seedlings than in etiolated seedlings, whereas GA 3β-hy mRNA accumulation was higher in etiolated seedlings. However, transfer of etiolated seedlings to light led to a 5-fold increase in the expression of both transcripts 4 h after transfer. GA 20-ox mRNA accumulation is regulated by both phytochromes A and B. Transfer to light also resulted in a 6-fold decrease in GA1 levels within 2 h. These results suggest that the light-induced drop in GA1 level is not achieved through regulation of GA 20-ox and GA 3β-hy mRNA accumulation. The application of exogenous GA1 to apical buds of etiolated seedlings prior to light treatments inhibited the light-induced accumulation of both GA 20-ox and GA 3β-hy mRNA, suggesting that negative feedback regulation is an important mechanism in the regulation of GA 20-ox and GA 3β-hy mRNA accumulation during de-etiolation of pea seedlings. PMID:10557226

  14. Investigating the Phylogenetic Range of Gibberellin Biosynthesis in Bacteria.

    PubMed

    Nagel, Raimund; Peters, Reuben J

    2017-04-01

    Certain plant-associated microbes can produce gibberellin (GA) phytohormones, as first described for the rice fungal pathogen Gibberella fujikuroi and, more recently, for bacteria, including several rhizobia and the rice bacterial pathogen Xanthomonas oryzae pv. oryzicola. The relevant enzymes are encoded by a biosynthetic operon that exhibits both a greater phylogenetic range and scattered distribution among plant-associated bacteria. Here, the phylogenetic distribution of this operon was investigated. To demonstrate conserved functionality, the enzymes encoded by the disparate operon from X. translucens pv. translucens, along with those from the most divergent example, found in Erwinia tracheiphila, were biochemically characterized. In both of these phytopathogens, the operon leads to production of the bioactive GA4. Based on these results, it seems that this operon is widely dedicated to GA biosynthesis. However, there is intriguing variation in the exact product. In particular, although all plant pathogens seem to produce bioactive GA4, rhizobia generally only produce the penultimate hormonal precursor GA9. This is suggested to reflect their distinct interactions with plants, because production of GA4 counteracts the jasmonic-acid-mediated defense response, reflecting the importance of wounds as the entry point for these phytopathogens, whereas such suppression presumably is detrimental in the rhizobial symbiotic relationship.

  15. Thermoinductive regulation of gibberellin metabolism in Thlaspi arvense L

    SciTech Connect

    Hazebroek, J.P.; Metzger, J.D. )

    1990-09-01

    Field pennycress (Thlaspi arvense L.) is a winter annual crucifer with a cold requirement for stem elongation and flowering. In the present study, the metabolism of exogenous ({sup 2}H)-ent-kaurenoic acid (KA) and ({sup 14}C)-gibberellin A{sub 12}-aldehyde (GA{sub 12}-aldehyde) was compared in thermo- and noninduced plants. Thermoinduction greatly altered both quantitative and qualitative aspects of ({sup 2}H)-KA metabolism in the shoot tips. The rate of disappearance of the parent compound was much greater in thermoinduced shoot tips. These results are consistent with the suggestion that the conversion of KA in to GAs is under thermoinductive control only in the shoot tip, the site of perception for thermoinductive temperatures in field pennycress. There were essentially no differences in the qualitative or quantitative distribution of metabolites formed following the application of ({sup 14}C)GA{sub 12}-aldehyde to the shoot tips of thermo- or noninduced plants. Thus, the apparent thermoinductive regulation of the KA metabolism into GAs is probably limited to the two metabolic steps involved in converting KA to GA{sub 12}-aldehyde.

  16. Gibberellin metabolism in isolated pea fruit tissue and intact fruits

    SciTech Connect

    Maki, S.; Brenner, M.L. )

    1989-04-01

    Gibberellins (GAs) have been shown by others to be required for normal development of pea fruit. Whether the pericarp of the developing pea fruit produces GAs in situ is not known. To determine if the pericarp has the capacity to produce GAs during fruit growth, the metabolism of the first two committed GAs in the biosynthetic pathway, ({sup 14}C)GA{sub 12}-aldehyde and ({sup 14}C)GA{sub 12} was examined in tissue obtained from pollinated, parthenocarpic, and control fruit over 4 days from treatment. ({sup 14}C)GA{sub 12}-aldehyde was converted primarily to conjugates, including ({sup 14}C)GA{sub 12}-aldehyde conjugate. ({sup 14}C)GA{sub 12} was converted to ({sup 14}C)GA{sub 53} in all tissue, but by day 4 only tissue from pollinated or parthenocarpic fruits showed sustained formation of ({sup 14}C)GA{sub 53}. When ({sup 14}C)GA{sub 12} is applied to 4-day-old fruits attached to the plants, the major product obtained after 24 hours is ({sup 14}C)GA{sub 20} (as identified by GC-MS). No transport to the developing seed was observed. These results indicate that the elongating fruit tissue has the capacity to produce GAs.

  17. Genetics of Dominant Gibberellin-Insensitive Dwarfism in Maize

    PubMed Central

    Harberd, N. P.; Freeling, M.

    1989-01-01

    D8 and Mpl1 are two dominant dwarfing mutations of maize. Although they differ in severity of dwarfism, both D8 and Mpl1 mutants are unresponsive to gibberellin (GA). Because of their close phenotypic resemblance to the recessive GA-sensitive dwarf mutants these dominant mutations may identify a gene whose product is involved in the reception of GA. With this possibility in mind we have studied the genetic properties of D8 and Mpl1. Both mutations map close to Adh1 on chromosome 1L. By marking normal and translocated 1L arms with different Adh1 electrophoretic mobility alleles, we investigated the effect of gene dosage on dominant dwarf phenotype. The results suggest that D8 and Mpl1 encode novel product functions and that these functions are relatively insensitive to the presence of the (presumed) wild-type product. Using X-ray induced chromosome breakage we created sectors of wild-type cells within D8 or Mpl1 tissue; these sectors were marked by the linked recessive lw mutation. The phenotypes of these sectors demonstrated that, at least in certain plant organs and tissues, dominant dwarfism can be an autonomous phenotype. These results are consistent with the hypothesis that the wild-type gene product acts as a GA receptor. The potential utility of dominant dwarf phenotype in plant developmental analysis is discussed, and possible mechanisms for the action of the D8 and Mpl1 mutations are considered. PMID:17246493

  18. Brassinosteroids Are Master Regulators of Gibberellin Biosynthesis in Arabidopsis

    PubMed Central

    Unterholzner, Simon J.; Rozhon, Wilfried; Papacek, Michael; Ciomas, Jennifer; Lange, Theo; Kugler, Karl G.; Mayer, Klaus F.; Sieberer, Tobias; Poppenberger, Brigitte

    2015-01-01

    Plant growth and development are highly regulated processes that are coordinated by hormones including the brassinosteroids (BRs), a group of steroids with structural similarity to steroid hormones of mammals. Although it is well understood how BRs are produced and how their signals are transduced, BR targets, which directly confer the hormone’s growth-promoting effects, have remained largely elusive. Here, we show that BRs regulate the biosynthesis of gibberellins (GAs), another class of growth-promoting hormones, in Arabidopsis thaliana. We reveal that Arabidopsis mutants deficient in BR signaling are severely impaired in the production of bioactive GA, which is correlated with defective GA biosynthetic gene expression. Expression of the key GA biosynthesis gene GA20ox1 in the BR signaling mutant bri1-301 rescues many of its developmental defects. We provide evidence that supports a model in which the BR-regulated transcription factor BES1 binds to a regulatory element in promoters of GA biosynthesis genes in a BR-induced manner to control their expression. In summary, our study underscores a role of BRs as master regulators of GA biosynthesis and shows that this function is of major relevance for the growth and development of vascular plants. PMID:26243314

  19. Brassinosteroids Are Master Regulators of Gibberellin Biosynthesis in Arabidopsis.

    PubMed

    Unterholzner, Simon J; Rozhon, Wilfried; Papacek, Michael; Ciomas, Jennifer; Lange, Theo; Kugler, Karl G; Mayer, Klaus F; Sieberer, Tobias; Poppenberger, Brigitte

    2015-08-01

    Plant growth and development are highly regulated processes that are coordinated by hormones including the brassinosteroids (BRs), a group of steroids with structural similarity to steroid hormones of mammals. Although it is well understood how BRs are produced and how their signals are transduced, BR targets, which directly confer the hormone's growth-promoting effects, have remained largely elusive. Here, we show that BRs regulate the biosynthesis of gibberellins (GAs), another class of growth-promoting hormones, in Arabidopsis thaliana. We reveal that Arabidopsis mutants deficient in BR signaling are severely impaired in the production of bioactive GA, which is correlated with defective GA biosynthetic gene expression. Expression of the key GA biosynthesis gene GA20ox1 in the BR signaling mutant bri1-301 rescues many of its developmental defects. We provide evidence that supports a model in which the BR-regulated transcription factor BES1 binds to a regulatory element in promoters of GA biosynthesis genes in a BR-induced manner to control their expression. In summary, our study underscores a role of BRs as master regulators of GA biosynthesis and shows that this function is of major relevance for the growth and development of vascular plants. © 2015 American Society of Plant Biologists. All rights reserved.

  20. Light-Stimulated Gibberellin Biosynthesis in Gibberella fujikuroi1

    PubMed Central

    Johnson, Stephen W.; Coolbaugh, Ronald C.

    1990-01-01

    Gibberellins (GAs) are a group of plant growth hormones that were first isolated from the fungus Gibberella fujikuroi. The biosynthesis of GA in liquid cultures of the fungus has been examined using high-performance liquid chromatography and combined gas chromatography-mass spectrometry. GA3 was the predominant GA in well-aerated cultures. GA4 and GA7, intermediates in GA3 biosynthesis, accumulated in cultures with low levels of dissolved oxygen, but were not detectable in more highly aerated cultures. Light stimulated the production of GA3 in G. fujikuroi cultures grown from young stock cultures. Cell-free enzyme studies revealed a significant stimulation in the levels of kaurenoic acid oxidation in cultures grown in the light in comparison with those grown in the dark. However, measurements of the relative rates of [14C]mevalonic acid incorporation into kaurene showed no effect of light on this early part of the pathway. Preliminary experiments indicated that blue light is most effective in enhancing kaurenoic acid oxidation. PMID:16667904

  1. Purification of gibberellin sub 53 -oxidase from spinach

    SciTech Connect

    Wilson, T.M.; Zeevaart, J.A.D. )

    1989-04-01

    Spinach is a long-day rosette plants, in which stem growth is mediated by gibberellins. It has been shown that two enzymatic steps, GA{sub 53}-oxidase and GA{sub 19}-oxidase, are controlled by light. To develop an understanding into this light regulation, purification of GA{sub 53}-oxidase has been undertaken. The original assay relied on the HPLC separation of the product and substrate, but was considered too slow for the development of a purification scheme. A TLC system was developed which in conjunction with improvements to the assay conditions was sensitive and gave rapid results. The partial purification of the GA{sub 53}-oxidase is achieved by a high speed centrifugation, 40-55% ammonium sulfate precipitation, an hydroxyapatite column, Sephadex G-100 column and an anion exchange FPLC column, Mono Q HR10/10, yielding 1000-fold purification and 15% recovery. Monoclonal antibodies to the protein will be raised and used to further characterize the enzyme.

  2. Relationships Among Goal Contents, Exercise Motivations, Physical Activity, and Aerobic Fitness in University Physical Education Courses.

    PubMed

    Sibley, Benjamin A; Bergman, Shawn M

    2016-04-01

    The current research examined the relationships among exercise goal contents, behavioral regulation, physical activity, and aerobic fitness within the context of eight-week university physical education courses. Participants were undergraduate students (M age = 20.2 year, SD = 2.3) enrolled in activity courses (N = 461) during the 2010 Fall semester. At pretest, participants completed a demographic survey, Behavioral Regulation in Exercise Questionnaire and the Goal Contents in Exercise Questionnaire. At eight-week posttest, participants completed the Physical Activity Questionnaire for Adults and the PACER aerobic fitness test. Relative intrinsic goal content was found to predict physical activity indirectly and aerobic fitness via behavioral regulation. Specific goal contents related to health management and skill development were found to predict physical activity and aerobic fitness via a fully mediated path through identified and intrinsic regulation. Results supported the efficacy of goal contents and self-determination theory in describing physical activity behavior and fitness. Examining specific types of goal contents and behavioral regulations revealed relationships that were masked by the utilization of omnibus scoring protocols.

  3. Antioxidant Contents and Antioxidant Activities of White and Colored Potatoes (Solanum tuberosum L.).

    PubMed

    Lee, Sang Hoon; Oh, Seung Hee; Hwang, In Guk; Kim, Hyun Young; Woo, Koan Sik; Woo, Shun Hee; Kim, Hong Sig; Lee, Junsoo; Jeong, Heon Sang

    2016-06-01

    This study was performed to evaluate and compare the antioxidant substance content and antioxidant activities of white (Superior) and colored (Hongyoung, Jayoung, Jasim, Seohong, and Jaseo) potatoes. The potatoes were extracted with 80% ethanol and were evaluated for the total polyphenol, flavonoid, and anthocyanin contents and for 1,1-diphenyl- 2-picrylhydrazyl (DPPH)/2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, reducing power, and ferrous metal ion chelating effect. The total polyphenol, flavonoid, and anthocyanin contents of Hongyoung and Jayoung were higher than white and other colored potatoes. All colored potato extracts, except for Jaseo and Seohong, showed higher ABTS radical scavenging activities than the general white potato extract. Hongyoung and Jayoung had the highest ABTS and DPPH radical scavenging activities. Optical density values for the reducing power of Jayoung and Jaseo at concentration of 2 mg/mL were 0.148 and 0.090, respectively. All colored potato extracts had lower ferrous metal ion chelating effect than the white potato. A significant (P<0.05) positive correlation was observed between total polyphenol content and total flavonoid content (r=0.919), anthocyanin content (r=0.992), and ABTS radical scavenging activity (r=0.897). Based on these results, this research may be useful in developing the Hongyoung and Jayoung cultivars with high antioxidant activities.

  4. Antioxidant Contents and Antioxidant Activities of White and Colored Potatoes (Solanum tuberosum L.)

    PubMed Central

    Lee, Sang Hoon; Oh, Seung Hee; Hwang, In Guk; Kim, Hyun Young; Woo, Koan Sik; Woo, Shun Hee; Kim, Hong Sig; Lee, Junsoo; Jeong, Heon Sang

    2016-01-01

    This study was performed to evaluate and compare the antioxidant substance content and antioxidant activities of white (Superior) and colored (Hongyoung, Jayoung, Jasim, Seohong, and Jaseo) potatoes. The potatoes were extracted with 80% ethanol and were evaluated for the total polyphenol, flavonoid, and anthocyanin contents and for 1,1-diphenyl- 2-picrylhydrazyl (DPPH)/2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, reducing power, and ferrous metal ion chelating effect. The total polyphenol, flavonoid, and anthocyanin contents of Hongyoung and Jayoung were higher than white and other colored potatoes. All colored potato extracts, except for Jaseo and Seohong, showed higher ABTS radical scavenging activities than the general white potato extract. Hongyoung and Jayoung had the highest ABTS and DPPH radical scavenging activities. Optical density values for the reducing power of Jayoung and Jaseo at concentration of 2 mg/mL were 0.148 and 0.090, respectively. All colored potato extracts had lower ferrous metal ion chelating effect than the white potato. A significant (P<0.05) positive correlation was observed between total polyphenol content and total flavonoid content (r=0.919), anthocyanin content (r=0.992), and ABTS radical scavenging activity (r=0.897). Based on these results, this research may be useful in developing the Hongyoung and Jayoung cultivars with high antioxidant activities. PMID:27390727

  5. Gibberellin Modulates Anther Development in Rice via the Transcriptional Regulation of GAMYB[W

    PubMed Central

    Aya, Koichiro; Ueguchi-Tanaka, Miyako; Kondo, Maki; Hamada, Kazuki; Yano, Kentaro; Nishimura, Mikio; Matsuoka, Makoto

    2009-01-01

    Gibberellins (GAs) play important roles in regulating reproductive development, especially anther development. Our previous studies revealed that the MYB transcriptional factor GAMYB, an important component of GA signaling in cereal aleurone cells, is also important for anther development. Here, we examined the physiological functions of GA during anther development through phenotypic analyses of rice (Oryza sativa) GA-deficient, GA-insensitive, and gamyb mutants. The mutants exhibited common defects in programmed cell death (PCD) of tapetal cells and formation of exine and Ubisch bodies. Microarray analysis using anther RNAs of these mutants revealed that rice GAMYB is involved in almost all instances of GA-regulated gene expression in anthers. Among the GA-regulated genes, we focused on two lipid metabolic genes, a cytochrome P450 hydroxylase CYP703A3 and β-ketoacyl reductase, both of which might be involved in providing a substrate for exine and Ubisch body. GAMYB specifically interacted with GAMYB binding motifs in the promoter regions in vitro, and mutation of these motifs in promoter-β-glucuronidase (GUS) transformants caused reduced GUS expression in anthers. Furthermore, a knockout mutant for CYP703A3 showed gamyb-like defects in exine and Ubisch body formation. Together, these results suggest that GA regulates exine formation and the PCD of tapetal cells and that direct activation of CYP703A3 by GAMYB is key to exine formation. PMID:19454733

  6. Tissue-Specific Regulation of Gibberellin Signaling Fine-Tunes Arabidopsis Iron-Deficiency Responses.

    PubMed

    Wild, Michael; Davière, Jean-Michel; Regnault, Thomas; Sakvarelidze-Achard, Lali; Carrera, Esther; Lopez Diaz, Isabel; Cayrel, Anne; Dubeaux, Guillaume; Vert, Grégory; Achard, Patrick

    2016-04-18

    Iron is an essential element for most living organisms. Plants acquire iron from the rhizosphere and have evolved different biochemical and developmental responses to adapt to a low-iron environment. In Arabidopsis, FIT encodes a basic helix-loop-helix transcription factor that activates the expression of iron-uptake genes in root epidermis upon iron deficiency. Here, we report that the gibberellin (GA)-signaling DELLA repressors contribute substantially in the adaptive responses to iron-deficient conditions. When iron availability decreases, DELLAs accumulate in the root meristem, thereby restraining root growth, while being progressively excluded from epidermal cells in the root differentiation zone. Such DELLA exclusion from the site of iron acquisition relieves FIT from DELLA-dependent inhibition and therefore promotes iron uptake. Consistent with this mechanism, expression of a non-GA-degradable DELLA mutant protein in root epidermis interferes with iron acquisition. Hence, spatial distribution of DELLAs in roots is essential to fine-tune the adaptive responses to iron availability.

  7. Karrikins delay soybean seed germination by mediating abscisic acid and gibberellin biogenesis under shaded conditions

    PubMed Central

    Meng, Yongjie; Chen, Feng; Shuai, Haiwei; Luo, Xiaofeng; Ding, Jun; Tang, Shengwen; Xu, Shuanshuan; Liu, Jianwei; Liu, Weiguo; Du, Junbo; Liu, Jiang; Yang, Feng; Sun, Xin; Yong, Taiwen; Wang, Xiaochun; Feng, Yuqi; Shu, Kai; Yang, Wenyu

    2016-01-01

    Karrikins (KAR) are a class of signal compounds, discovered in wildfire smoke, which affect seed germination. Currently, numerous studies have focused on the model plant Arabidopsis in the KAR research field, rather than on crops. Thus the regulatory mechanisms underlying KAR regulation of crop seed germination are largely unknown. Here, we report that KAR delayed soybean seed germination through enhancing abscisic acid (ABA) biosynthesis, while impairing gibberellin (GA) biogenesis. Interestingly, KAR only retarded soybean seed germination under shaded conditions, rather than under dark and white light conditions, which differs from in Arabidopsis. Phytohormone quantification showed that KAR enhanced ABA biogenesis while impairing GA biosynthesis during the seed imbibition process, and subsequently, the ratio of active GA4 to ABA was significantly reduced. Further qRT-PCR analysis showed that the transcription pattern of genes involved in ABA and GA metabolic pathways are consistent with the hormonal measurements. Finally, fluridone, an ABA biogenesis inhibitor, remarkably rescued the delayed-germination phenotype of KAR-treatment; and paclobutrazol, a GA biosynthesis inhibitor, inhibited soybean seed germination. Taken together, these evidences suggest that KAR inhibit soybean seed germination by mediating the ratio between GA and ABA biogenesis. PMID:26902640

  8. To Gibberellins and Beyond! Surveying the Evolution of (Di)terpenoid Metabolism

    PubMed Central

    Zi, Jiachen; Mafu, Sibongile; Peters, Reuben J.

    2014-01-01

    The diterpenoids are classically defined by their composition, four isoprenyl units (20 carbons), and are generally derived from [E,E,E]-geranylgeranyl diphosphate (GGPP). Such metabolism seems to be ancient and has been extensively diversified, with ~12,000 diterpenoid natural products known. Particularly notable are the gibberellin phytohormones, whose requisite biosynthesis has provided a genetic reservoir giving rise to not only a large super-family of ~7,000 diterpenoids, but to some degree all plant terpenoid natural products. This review focuses on the diterpenoids, particularly the defining biosynthetic characteristics of the major superfamilies defined by the cyclization and/or rearrangement of GGPP catalyzed by diterpene synthases/cyclases, although some discussion also is provided of the important subsequent elaboration in those few cases where molecular genetic information is available. In addition, the array of biological activity providing the selective pressure driving the observed gene family expansion and diversification, along with biosynthetic gene clustering, will be discussed as well. PMID:24471837

  9. Endogenous gibberellins and stem growth as related to photoperiod in Silene armeria L

    SciTech Connect

    Talon, M.; Zeevaart, J.A.D. )

    1989-04-01

    The early 13-hydroxylation gibberellin (GA) pathway operates in the long-day plant Silene armeria grown under both long-day (LD) and short-day (SD) conditions. Thus, induction of stem growth must be related to quantitative changes in GA pattern. Using GC-SIM-MS and GAs labeled with stable isotopes as internal standards, the levels of GA{sub 53}, GA{sub 19}, GA{sub 20}, and GA{sub 1} were measured in shoots and various organs of plants grown under different photoperiods. Exposure to 8 LD decreased the levels of GA{sub 53} and GA{sub 19}, and increased the levels of GA{sub 20} and particularly of GA{sub 1}; the latter GA accumulated to very high levels in expanding leaves and tips. When plants were exposed to LD, followed by SD, GA levels decreased, and the relative increases in stem length were correlated with the level of GA{sub 1} at the time the plants were returned to SD. These observations suggest that GA{sub 53}-oxidase, and probable also GA{sub 19}-oxidase, are under photoperiodic control. Furthermore, GA{sub 1} appears to be active per se in Silene in causing stem growth, since its level was always correlated with the degree of stem elongation.

  10. Brassinosteroid Regulates Cell Elongation by Modulating Gibberellin Metabolism in Rice[C][W][OPEN

    PubMed Central

    Tong, Hongning; Xiao, Yunhua; Liu, Dapu; Gao, Shaopei; Liu, Linchuan; Yin, Yanhai; Jin, Yun; Qian, Qian; Chu, Chengcai

    2014-01-01

    Brassinosteroid (BR) and gibberellin (GA) are two predominant hormones regulating plant cell elongation. A defect in either of these leads to reduced plant growth and dwarfism. However, their relationship remains unknown in rice (Oryza sativa). Here, we demonstrated that BR regulates cell elongation by modulating GA metabolism in rice. Under physiological conditions, BR promotes GA accumulation by regulating the expression of GA metabolic genes to stimulate cell elongation. BR greatly induces the expression of D18/GA3ox-2, one of the GA biosynthetic genes, leading to increased GA1 levels, the bioactive GA in rice seedlings. Consequently, both d18 and loss-of-function GA-signaling mutants have decreased BR sensitivity. When excessive active BR is applied, the hormone mostly induces GA inactivation through upregulation of the GA inactivation gene GA2ox-3 and also represses BR biosynthesis, resulting in decreased hormone levels and growth inhibition. As a feedback mechanism, GA extensively inhibits BR biosynthesis and the BR response. GA treatment decreases the enlarged leaf angles in plants with enhanced BR biosynthesis or signaling. Our results revealed a previously unknown mechanism underlying BR and GA crosstalk depending on tissues and hormone levels, which greatly advances our understanding of hormone actions in crop plants and appears much different from that in Arabidopsis thaliana. PMID:25371548

  11. OsGSR1 is involved in crosstalk between gibberellins and brassinosteroids in rice.

    PubMed

    Wang, Li; Wang, Zhen; Xu, Yunyuan; Joo, Se-Hwan; Kim, Seong-Ki; Xue, Zhen; Xu, Zhihong; Wang, Zhiyong; Chong, Kang

    2009-02-01

    Gibberellins (GAs) and brassinosteroids (BRs), two growth-promoting phytohormones, regulate many common physiological processes. Their interactions at the molecular level remain unclear. Here, we demonstrate that OsGSR1, a member of the GAST (GA-stimulated transcript) gene family, is induced by GA and repressed by BR. RNA interference (RNAi) transgenic rice plants with reduced OsGSR1 expression show phenotypes similar to plants deficient in BR, including short primary roots, erect leaves and reduced fertility. The OsGSR1 RNAi transgenic rice shows a reduced level of endogenous BR, and the dwarf phenotype could be rescued by the application of brassinolide. The yeast two-hybrid assay revealed that OsGSR1 interacts with DIM/DWF1, an enzyme that catalyzes the conversion from 24-methylenecholesterol to campesterol in BR biosynthesis. These results suggest that OsGSR1 activates BR synthesis by directly regulating a BR biosynthetic enzyme at the post-translational level. Furthermore, OsGSR1 RNAi plants show a reduced sensitivity to GA treatment, an increased expression of the GA biosynthetic gene OsGA20ox2, which is feedback inhibited by GA signaling, and an elevated level of endogenous GA: together, these suggest that OsGSR1 is a positive regulator of GA signaling. These results demonstrate that OsGSR1 plays important roles in both BR and GA pathways, and also mediates an interaction between the two signaling pathways.

  12. Karrikins delay soybean seed germination by mediating abscisic acid and gibberellin biogenesis under shaded conditions.

    PubMed

    Meng, Yongjie; Chen, Feng; Shuai, Haiwei; Luo, Xiaofeng; Ding, Jun; Tang, Shengwen; Xu, Shuanshuan; Liu, Jianwei; Liu, Weiguo; Du, Junbo; Liu, Jiang; Yang, Feng; Sun, Xin; Yong, Taiwen; Wang, Xiaochun; Feng, Yuqi; Shu, Kai; Yang, Wenyu

    2016-02-23

    Karrikins (KAR) are a class of signal compounds, discovered in wildfire smoke, which affect seed germination. Currently, numerous studies have focused on the model plant Arabidopsis in the KAR research field, rather than on crops. Thus the regulatory mechanisms underlying KAR regulation of crop seed germination are largely unknown. Here, we report that KAR delayed soybean seed germination through enhancing abscisic acid (ABA) biosynthesis, while impairing gibberellin (GA) biogenesis. Interestingly, KAR only retarded soybean seed germination under shaded conditions, rather than under dark and white light conditions, which differs from in Arabidopsis. Phytohormone quantification showed that KAR enhanced ABA biogenesis while impairing GA biosynthesis during the seed imbibition process, and subsequently, the ratio of active GA4 to ABA was significantly reduced. Further qRT-PCR analysis showed that the transcription pattern of genes involved in ABA and GA metabolic pathways are consistent with the hormonal measurements. Finally, fluridone, an ABA biogenesis inhibitor, remarkably rescued the delayed-germination phenotype of KAR-treatment; and paclobutrazol, a GA biosynthesis inhibitor, inhibited soybean seed germination. Taken together, these evidences suggest that KAR inhibit soybean seed germination by mediating the ratio between GA and ABA biogenesis.

  13. Emission of ent-kaurene, a diterpenoid hydrocarbon precursor for gibberellins, into the headspace from plants.

    PubMed

    Otsuka, Minoru; Kenmoku, Hiromichi; Ogawa, Mikihiro; Okada, Kazunori; Mitsuhashi, Wataru; Sassa, Takeshi; Kamiya, Yuji; Toyomasu, Tomonobu; Yamaguchi, Shinjiro

    2004-09-01

    ent-Kaurene is a tetracyclic hydrocarbon precursor for gibberellins (GAs) in plants and fungi. To address whether fungal GA biosynthesis enzymes function in plants, we generated transgenic Arabidopsis plants overexpressing ent-kaurene synthase (GfCPS/KS) from a GA-producing fungus Gibberella fujikuroi. GfCPS/KS catalyzes a two-step reaction corresponding to ent-copalyl diphosphate synthase (CPS) and ent-kaurene synthase (KS) activities in plants. When GfCPS/KS was overexpressed and targeted to plastids, a range of GA-deficient phenotypes of the ga1-3 and ga2-1 mutants (defective in CPS and KS, respectively) were restored to wild type. Unexpectedly, the transgenic lines overproducing GfCPS/KS emitted the GA precursor ent-kaurene into the headspace besides its accumulation in the plant body. When co-cultivated with the ent-kaurene overproducers in a closed environment, the airborne ent-kaurene was able to fully complement the dwarf phenotype of ga1-3 and ga2-1 mutants, but not that of the ga3-1 mutant (defective in ent-kaurene oxidase). These results suggest that ent-kaurene may be efficiently metabolized into bioactive GAs in Arabidopsis when supplied as a volatile. We also provide evidence that ent-kaurene is released in the headspace of wild-type Chamaecyparis obtusa and Cryptomeria japonica plants, suggesting the occurrence of this hydrocarbon GA precursor as a volatile in nature.

  14. In vivo gibberellin biosynthesis in endosperm of Sechium edule Sw. seeds

    SciTech Connect

    Ceccarelli, N.; Lorenzi, R. )

    1990-07-01

    Biosynthesis of gibberellins (GAs) was studied in vivo in endosperms of Sechium edule Sw. Exogenous ent-({sup 14}C)kaurene was metabolized into four major products: GA{sub 12}, GA{sub 4}, GA{sub 7} and 16,17-dihydro-16-hydroxy-GA{sub 15} alcohol glucoside. Other minor metabolites were also observed including ent-kaurenol and ent-kaurenal. Conversion of ent-({sup 14}C)kaurene to ent-karuenol glucoside by endosperm cell-free preparations in the presence of UDPG was observed. However, the finding was not confirmed in in vivo studies and is probably artifactual. Overall evidence coming from the analysis of endogenous GAs and in vitro and in vivo biosynthetic studies are discussed in relation to the possible existence in the Sechium seeds of a different route, along with the known pathway, branching from ent-kaurene or ent-7-{alpha}-hydroxykaurenoic acid and this also leading to biologically active GAs.

  15. Partial purification of gibberellin oxidases from spinach leaves. [Spinacia oleracea L

    SciTech Connect

    Gilmour, S.J.; Bleecker, A.B.; Zeevaart, J.A.D.

    1987-09-01

    Four enzyme activities catalyzing the following oxidative steps in the gibberellin (GA) biosynthetic pathway have been extracted from spinach (Spinacia oleracea L.) leaves after exposure to 8 long days: GA/sub 12/ ..-->.. GA/sub 53/ ..-->.. GA/sub 44/ ..-->.. GA/sub 19/ ..-->.. GA/sub 20/. Two of these, GA/sub 53/ oxidase and GA/sup 19/ oxidase, were separable from the other two, GA/sub 44/ oxidase and GA/sub 12/ 13-hydroxylase, by anion exchange high performance liquid chromatography (HPLC). Apparent molecular weights of the four enzymes as determined by gel filtration HLPL are: GA/sub 12/ 13-hydroxylase, 28,400; GA/sub 43/ oxidase, 42,500; GA/sub 44/ oxidase, 38,100; GA/sub 19/ oxidase, 39,500. GA/sub 44/ oxidase was purified approximately 100-fold in 0.3% yield by a combination of ammonium sulfate fractionation, anion exchange HPLC, phenyl-Sepharose chromatography and gel filtration HLPC.

  16. Strawberries from integrated and organic production: mineral contents and antioxidant activity.

    PubMed

    Kristl, Janja; Krajnc, Andreja Urbanek; Kramberger, Branko; Mlakar, Silva Grobelnik

    2013-01-01

    As the nutritional quality of food is becoming increasingly more important for consumers, significant attention needs to be devoted to agricultural practices and their influences on the nutrient contents in food. The presented investigation studied the mineral contents and antioxidant activities in the fruits of four organically-grown strawberry cultivars 'St. Pierre', 'Elsanta', 'Sugar Lia' and 'Thuchampion' when compared to those of integrated-grown plants. The strawberries were digested and analyzed for K, Mg, Fe, Zn, Cu, and Mn using an atomic absorption spectrometer, whilst P was analyzed using a vanadate-molybdate method. In addition, antioxidant activity was estimated by using the ABTS assay. The results showed that the mineral contents and antioxidant activities in strawberries depends on the cultivar, and its production system. Organically-grown fruits showed higher antioxidant activities and Cu content than the integrated fruits, whilst the integrated fruits were superior in their contents of P, K, Mg, Fe and Mn. All the cultivars showed similar Zn content, probably reflecting the fact that the Zn content in strawberries does not depend on the cultivar.

  17. Gibberellin A sub 3 is biosynthesized from gibberellin A sub 20 via gibberellin A sub 5 in shoots of Zea mays L

    SciTech Connect

    Fujioka, Shozo; Spray, C.R.; Phinney, B.O. ); Gaskin, P.; MacMillan, J. ); Yamane, Hisakazu Univ. of Tokyo ); Takahashi, Nobutaka )

    1990-09-01

    (17-{sup 13}C, {sup 3}H)-Labeled gibberellin A{sub 20} (GA{sub 20}), GA{sub 5}, and GA{sub 1} were fed to homozygous normal (+/+), heterozygous dominant dwarf (D8/+), and homozygous dominant dwarf (D8/D8) seedlings of Zea mays L. (maize). {sup 13}C-Labeled GA{sub 29}, GA{sub 8}, GA{sub 5}, GA{sub 1}, and 3-epi-GA{sub 1}, as well as unmetabolized ({sup 13}C)GA{sub 20}, were identified by gas chromatography-selected ion monitoring (GC-SIM) from feeds of (17-{sup 13}C, {sup 3}H)GA{sub 20} to all three genotypes. {sup 13}C-Labeled GA{sub 8} and 3-epi-G{sub 1}, as well as unmetabolized ({sup 13}C)GA{sub 1}, were identified by GC-SIM from feeds of (17-{sup 13}C, {sup 3}H)GA{sub 1} to all three genotypes. From feeds of (17-{sup 13}C, {sup 3}H)GA{sub 5}, {sup 13}C-labeled GA{sub 3} and the GA{sub 3}-isolactone, as well as unmetabolized ({sup 13}C)GA{sub 5}, were identified by GC-SIM from +/+ and D8/D8, and by full scan GC-MS from D8/+. No evidence was found for the metabolism of (17-{sup 13}C, {sup 3}H)GA{sub 5} to ({sup 13}C)GA{sub 1}, either by full scan GC-mass spectrometry or by GC-SIM. The results demonstrate the presence in maize seedlings of three separate branches from GA{sub 20}, as follows: (a) GA{sub 20} {yields} GA{sub 1} {yields} GA{sub 8}; (b) GA{sub 20} {yields} GA{sub 5} {yields} GA{sub 3}; and (c) GA{sub 20} {yields} GA{sub 29}. The in vivo biogenesis of GA{sub 3} from GA{sub 5}, as well as the origin of GA{sub 5} from GA{sub 20}, are conclusively established for the first time in a higher plant (maize shoots).

  18. Patient-reported physical activity questionnaires: A systematic review of content and format

    PubMed Central

    2012-01-01

    Background Many patients with chronic illness are limited in their physical activities. This systematic review evaluates the content and format of patient-reported outcome (PRO) questionnaires that measure physical activity in elderly and chronically ill populations. Methods Questionnaires were identified by a systematic literature search of electronic databases (Medline, Embase, PsychINFO & CINAHL), hand searches (reference sections and PROQOLID database) and expert input. A qualitative analysis was conducted to assess the content and format of the questionnaires and a Venn diagram was produced to illustrate this. Each stage of the review process was conducted by at least two independent reviewers. Results 104 questionnaires fulfilled our criteria. From these, 182 physical activity domains and 1965 items were extracted. Initial qualitative analysis of the domains found 11 categories. Further synthesis of the domains found 4 broad categories: 'physical activity related to general activities and mobility', 'physical activity related to activities of daily living', 'physical activity related to work, social or leisure time activities', and '(disease-specific) symptoms related to physical activity'. The Venn diagram showed that no questionnaires covered all 4 categories and that the '(disease-specific) symptoms related to physical activity' category was often not combined with the other categories. Conclusions A large number of questionnaires with a broad range of physical activity content were identified. Although the content could be broadly organised, there was no consensus on the content and format of physical activity PRO questionnaires in elderly and chronically ill populations. Nevertheless, this systematic review will help investigators to select a physical activity PRO questionnaire that best serves their research question and context. PMID:22414164

  19. A genetic test of bioactive gibberellins as regulators of heterosis in maize.

    PubMed

    Auger, D L; Peters, E M; Birchler, J A

    2005-01-01

    This study tested the hypothesis that gibberellin levels were responsible for the superior growth habit of hybrids (i.e., heterosis). If this were true, plants reduced in their capacity to produce gibberellin, such as maize plants homozygous for dwarf1 (d1), should display a lesser heterotic response. The d1 mutation was introgressed into two inbred lines of maize, B73 and Mo17, for seven generations. Plants segregating for the dwarf phenotype were produced both by self-fertilizing the introgressed inbred lines and by making reciprocal crosses between them to produce hybrids. Measurements were made of several physical traits. The results indicated that the hybrid dwarf plants experienced no loss of heterosis relative to their normal siblings. These results exclude the possibility that modulation of bioactive gibberellins is a major underlying basis of the heterotic response.

  20. [Dynamic change of active component content in different parts of Prunella vulgaris].

    PubMed

    Wang, Yuxia; Yin, Jinbao; Guo, Qiaosheng; Xiao, Yunhua

    2011-03-01

    Through determination of the dynamic change of the active component in different parts of Prunella vulgaris at different growth stages, to find the optimal harvest time. Total flavonoids content was determined by using the spectrophotometric method, and the content of ursolic acid and oleanolic acid was determined by HPLC. The contents of ash and extract were determined according to the methods in Chinese Pharmacopeia (2005 edition). There existed the active components in all parts of P. vulgaris, but the active component contents in different parts of P. vulgaris of at different growth stages, changed very obviously. In Yangtze-Huaihai region, the optimal harvest time of Prunella spike best harvest is at the end of June, and Prunellastem at the end of May. All parts of P. vulgaris have medicinal value.

  1. Effects of Copper Pollution on the Phenolic Compound Content, Color, and Antioxidant Activity of Wine.

    PubMed

    Sun, Xiangyu; Ma, Tingting; Han, Luyang; Huang, Weidong; Zhan, Jicheng

    2017-05-03

    The effects of copper pollution on the polyphenol content, color, and antioxidant activity of wine, as well as correlations among these factors, were investigated. Copper had clear influences on wine polyphenol content. At low copper concentrations, the concentrations of nearly all polyphenols increased, and the antioxidant activity values of the wine also increased. When the copper concentration reached the lowest level of the medium copper range (9.6~16 mg/L), most of the indices also improved. When the copper concentrations reached the latter part of the medium copper range (19.2 and 22.4 mg/L), many of the tested indices began to decrease. Furthermore, when the copper concentration reached the high ranges (32, 64, and 96 mg/L), the polyphenol content, CIELAB color parameters, and antioxidant activity of wine were substantially decreased, indicating the need to control increasing copper content in grape must.

  2. Antioxidant activity of some Moroccan marine microalgae: Pufa profiles, carotenoids and phenolic content.

    PubMed

    Maadane, Amal; Merghoub, Nawal; Ainane, Tarik; El Arroussi, Hicham; Benhima, Redouane; Amzazi, Saaid; Bakri, Youssef; Wahby, Imane

    2015-12-10

    In order to promote Moroccan natural resources, this study aims to evaluate the potential of microalgae isolated from Moroccan coastlines, as new source of natural antioxidants. Different extracts (ethanolic, ethanol/water and aqueous) obtained from 9 microalgae strains were screened for their in vitro antioxidant activity using DPPH free radical-scavenging assay. The highest antioxidant potentials were obtained in Dunalliela sp., Tetraselmis sp. and Nannochloropsis gaditana extracts. The obtained results indicate that ethanol extract of all microalgae strains exhibit higher antioxidant activity, when compared to water and ethanol/water extracts. Therefore, total phenolic and carotenoid content measurement were performed in active ethanol extracts. The PUFA profiles of ethanol extracts were also determined by GC/MS analysis. The studied microalgae strains displayed high PUFA content ranging from 12.9 to 76.9 %, total carotenoids content varied from 1.9 and 10.8mg/g of extract and total polyphenol content varied from 8.1 to 32.0mg Gallic acid Equivalent/g of extract weight. The correlation between the antioxidant capacities and the phenolic content and the carotenoids content were found to be insignificant, indicating that these compounds might not be major contributor to the antioxidant activity of these microalgae. The microalgae extracts exerting the high antioxidant activity are potential new source of natural antioxidants. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Phenolic content and antioxidant and antimutagenic activities in tomato peel, seeds, and byproducts.

    PubMed

    Valdez-Morales, Maribel; Espinosa-Alonso, Laura Gabriela; Espinoza-Torres, Libia Citlali; Delgado-Vargas, Francisco; Medina-Godoy, Sergio

    2014-06-11

    The phenolic content and antioxidant and antimutagenic activities from the peel and seeds of different tomato types (grape, cherry, bola and saladette type), and simulated tomato industrial byproducts, were studied. Methanolic extracts were used to quantify total phenolic content, groups of phenolic compounds, antioxidant activities, and the profile of phenolic compounds (by HPLC-DAD). Antimutagenic activity was determined by Salmonella typhimurium assay. The total phenolic content and antioxidant activity of tomato and tomato byproducts were comparable or superior to those previously reported for whole fruit and tomato pomace. Phenolic compounds with important biological activities, such as caffeic acid, ferulic acid, chlorogenic acids, quercetin-3-β-O-glycoside, and quercetin, were quantified. Differences in all phenolic determinations due to tomato type and part of the fruit analyzed were observed, peel from grape type showing the best results. Positive antimutagenic results were observed in all samples. All evaluated materials could be used as a source of potential nutraceutical compounds.

  4. Active retrieval facilitates across-episode binding by modulating the content of memory

    PubMed Central

    Bridge, Donna J.; Voss, Joel L.

    2014-01-01

    The contents of memory can be updated when information from the current episode is bound with content retrieved from previous episodes. Little is known regarding factors that determine the memory content that is subject to this across-episode binding. We tested whether across-episode binding preferentially occurs for memory content that is currently “active” and identified relevant neural correlates. After studying objects at specific locations on scene backgrounds, subjects performed one of two retrieval tasks for the objects on different scene backgrounds. In an active condition, subjects recalled object locations, whereas subjects merely dragged objects to predetermined locations in a passive condition. Immediately following each object-location retrieval event, a novel face appeared on a blank screen. We hypothesized that the original episode content would be active in memory during face encoding in the active condition, but not in the passive condition (despite seeing the same content in both conditions). A ramification of the active condition would thus be preferential binding of original episode content to novel faces, with no such across-episode binding in the passive condition. Indeed, memory for faces was better when tested on the original background scenes in the active relative to passive condition, indicating that original episode content was bound with the active condition faces, whereas this occurred to a lesser extent for the passive condition faces. Likewise, early-onset negative ERP effects reflected binding of the face to the original episode content in the active but not the passive condition. In contrast, binding in the passive condition occurred only when faces were physically displayed on the original scenes during recognition testing, and a very similar early-onset negative ERP effect signaled binding in this condition. ERP correlates of binding were thus similar for across-episode and within-episode binding (and were distinct from other

  5. Seasonal dynamics of total flavonoid contents and antioxidant activity of Dryopteris erythrosora.

    PubMed

    Xie, Yinghua; Zheng, Yunxia; Dai, Xiling; Wang, Quanxi; Cao, Jianguo; Xiao, Jianbo

    2015-11-01

    The seasonal dynamics of the total flavonoid contents in various parts of Dryopteris erythrosora, a traditional Chinese medicinal fern, and their antioxidant activity were investigated. The total flavonoids content in various parts of D. erythrosora showed an obvious seasonal dynamic change. The total flavonoid contents in stems (from 4.3% to 12.5%) were much higher than that in leaves with an average content of 2.01%. In spring, the total flavonoid contents in stems were relatively low, but increased rapidly from summer to winter. However, the seasonal dynamics of total flavonoid contents in leaves showed different model. The total flavonoid contents in the stems showed a negative correlation with that in the leaves from January to July. The correlation coefficient of about -0.7 was obtained. The antioxidant activity of the extracts also altered in proportion to the change of total flavonoid contents. In general, the extracts from stems always showed highest antioxidant potentials and it was suggested that the stems can be used as crude medicine.

  6. Computational gibberellin-binding channel discovery unraveling the unexpected perception mechanism of hormone signal by gibberellin receptor.

    PubMed

    Hao, Ge-Fei; Yang, Sheng-Gang; Yang, Guang-Fu; Zhan, Chang-Guo

    2013-09-15

    Gibberellins (GAs) are phytohormones essential for many developmental processes in plants. In this work, fundamental mechanism of hormone perception by receptor GID1 has been studied by performing computational simulations, revealing a new GA-binding channel of GID1 and a novel hormone perception mechanism involving only one conformational state of GID1. The novel hormone perception mechanism demonstrated here is remarkably different from the previously proposed/speculated mechanism [Murase et al., Nature 2008, 456, 459] involving two conformational states ("OPEN" and "CLOSED") of GID1. According to the new perception mechanism, GA acts as a "conformational stabilizer," rather than the previously speculated "allosteric inducer," to induce the recognition of protein DELLA by GID1. The novel mechanistic insights obtained in this study provide a new starting point for further studies on the detailed molecular mechanisms of GID1 interacting with DELLA and various hormones and for mechanism-based rational design of novel, potent growth regulators that target crops and ornamental plants.

  7. Thermal properties of ration components as affected by moisture content and water activity during freezing.

    PubMed

    Li, J; Chinachoti, P; Wang, D; Hallberg, L M; Sun, X S

    2008-11-01

    Beef roast with vegetables is an example of a meal, ready-to-eat (MRE) ration entrée. It is a mixture of meat, potato, mushroom, and carrot with a gravy sauce. The thermal properties of each component were characterized in terms of freezing point, latent heat, freezable and unfreezable water contents, and enthalpy during freezing using differential scanning calorimetry. Freezing and thawing curves and the effect of freezing and thawing cycles on thermal properties were also evaluated. The freezing points of beef, potato, mushroom, and sauce were all in the range of -5.1 to -5.6 degrees C, but moisture content, water activity, latent heat, freezable and unfreezable water contents, and enthalpy varied among these components. Freezing temperature greatly affected the unfrozen water fraction. The unfreezable water content (unfrozen water fraction at -50 degrees C) of ration components was in the range of 8.2% to 9.7%. The freezing and thawing curves of vegetables with sauce differed from those of beef but took similar time to freeze or thaw. Freezing and thawing cycles did not greatly affect the thermal properties of each component. Freezing point and latent heat were reduced by decreasing moisture content and water activity of each component. Water activity was proportionally linear to freezing point at a(w) > 0.88, and moisture content was proportionally linear to freezable water content in all ration components. Water was not available for freezing when moisture content was reduced to 28.8% or less. This study indicates that moisture content and water activity are critical factors affecting thermal behavior of ration components during freezing.

  8. Aerobic and resistance training do not influence plasma carnosinase content or activity in type 2 diabetes.

    PubMed

    Stegen, Sanne; Sigal, Ronald J; Kenny, Glen P; Khandwala, Farah; Yard, Benito; De Heer, Emile; Baelde, Hans; Peersman, Wim; Derave, Wim

    2015-10-01

    A particular allele of the carnosinase gene (CNDP1) is associated with reduced plasma carnosinase activity and reduced risk for nephropathy in diabetic patients. On the one hand, animal and human data suggest that hyperglycemia increases plasma carnosinase activity. On the other hand, we recently reported lower carnosinase activity levels in elite athletes involved in high-intensity exercise compared with untrained controls. Therefore, this study investigates whether exercise training and the consequent reduction in hyperglycemia can suppress carnosinase activity and content in adults with type 2 diabetes. Plasma samples were taken from 243 males and females with type 2 diabetes (mean age = 54.3 yr, SD = 7.1) without major microvascular complications before and after a 6-mo exercise training program [4 groups: sedentary control (n = 61), aerobic exercise (n = 59), resistance exercise (n = 63), and combined exercise training (n = 60)]. Plasma carnosinase content and activity, hemoglobin (Hb) A1c, lipid profile, and blood pressure were measured. A 6-mo exercise training intervention, irrespective of training modality, did not decrease plasma carnosinase content or activity in type 2 diabetic patients. Plasma carnosinase content and activity showed a high interindividual but very low intraindividual variability over the 6-mo period. Age and sex, but not Hb A1c, were significantly related to the activity or content of this enzyme. It can be concluded that the beneficial effects of exercise training on the incidence of diabetic complications are probably not related to a lowering effect on plasma carnosinase content or activity. Copyright © 2015 the American Physiological Society.

  9. Polyphenol content and antioxidant activity of fourteen wild edible fruits from Burkina Faso.

    PubMed

    Lamien-Meda, Aline; Lamien, Charles Euloge; Compaoré, Moussa M Y; Meda, Roland N T; Kiendrebeogo, Martin; Zeba, Boukare; Millogo, Jeanne F; Nacoulma, Odile G

    2008-03-06

    A total of fourteen (14) species of wild edible fruits from Burkina Faso were analyzed for their phenolic and flavonoid contents, and their antioxidant activities using the DPPH, FRAP and ABTS methods. The data obtained show that the total phenolic and total flavonoid levels were significantly higher in the acetone than in the methanol extracts.Detarium microcarpum fruit had the highest phenolic and the highest flavonoid content,followed by that of Adansonia digitata, Ziziphus mauritiana, Ximenia americana and Lannea microcarpa. Significant amounts of total phenolics were also detected in the other fruit species in the following order of decreasing levels: Tamarindus indica > Sclerocaryabirrea > Dialium guineense > Gardenia erubescens > Diospyros mespiliformis > Parkiabiglobosa > Ficus sycomorus > Vitellaria paradoxa. Detarium microcarpum fruit also showed the highest antioxidant activity using the three antioxidant assays. Fruits with high antioxidant activities were also found to possess high phenolic and flavonoid contents. There was a strong correlation between total phenolic and flavonoid levels and antioxidant activities.

  10. 77 FR 75198 - Standard Format and Content for Post-Shutdown Decommissioning Activities Report

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-19

    ...The U.S. Nuclear Regulatory Commission (NRC) is issuing for public comment draft regulatory guide (DG), DG-1272, ``Standard Format and Content for Post-shutdown Decommissioning Activities Report.'' This guide describes a method that the NRC staff considers acceptable for use in complying with the Commission's requirements regarding the submission of a post-shutdown decommissioning activities......

  11. 78 FR 38739 - Standard Format and Content for Post-Shutdown Decommissioning Activities Report

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-27

    ...The U.S. Nuclear Regulatory Commission (NRC) is issuing Revision 1 of Regulatory Guide (RG) 1.185, ``Standard Format and Content for Post-shutdown Decommissioning Activities Report.'' This guide describes a method that the NRC staff considers acceptable for use in complying with the Commission's requirements regarding the submission of a post-shutdown decommissioning activities report...

  12. Comparing Primary Student Teachers' Attitudes, Subject Knowledge and Pedagogical Content Knowledge Needs in a Physics Activity

    ERIC Educational Resources Information Center

    Johnston, Jane; Ahtee, Maija

    2006-01-01

    This research explores and compares primary student teachers' attitudes, subject knowledge and pedagogical content knowledge (PCK) in physics in two institutions in England and Finland, using a practical physics activity and questionnaire. Teaching of physics activities was rated unpopular both in Finland and England, although English students…

  13. Elementary Physical Education Teachers' Content Knowledge of Physical Activity and Health-Related Fitness

    ERIC Educational Resources Information Center

    Santiago, Jose A.; Disch, James G.; Morales, Julio

    2012-01-01

    The purpose of this study was to examine elementary physical education teachers' content knowledge of physical activity and health-related fitness. Sixty-four female and 24 male teachers completed the Appropriate Physical Activity and Health-Related Fitness test. Descriptive statistics results indicated that the mean percentage score for the test…

  14. Elementary Physical Education Teachers' Content Knowledge of Physical Activity and Health-Related Fitness

    ERIC Educational Resources Information Center

    Santiago, Jose A.; Disch, James G.; Morales, Julio

    2012-01-01

    The purpose of this study was to examine elementary physical education teachers' content knowledge of physical activity and health-related fitness. Sixty-four female and 24 male teachers completed the Appropriate Physical Activity and Health-Related Fitness test. Descriptive statistics results indicated that the mean percentage score for the test…

  15. Newspaper Content Analysis in Evaluation of a Community-Based Participatory Project to Increase Physical Activity

    ERIC Educational Resources Information Center

    Granner, Michelle L.; Sharpe, Patricia A.; Burroughs, Ericka L.; Fields, Regina; Hallenbeck, Joyce

    2010-01-01

    This study conducted a newspaper content analysis as part of an evaluation of a community-based participatory research project focused on increasing physical activity through policy and environmental changes, which included activities related to media advocacy and media-based community education. Daily papers (May 2003 to December 2005) from both…

  16. Comparing Primary Student Teachers' Attitudes, Subject Knowledge and Pedagogical Content Knowledge Needs in a Physics Activity

    ERIC Educational Resources Information Center

    Johnston, Jane; Ahtee, Maija

    2006-01-01

    This research explores and compares primary student teachers' attitudes, subject knowledge and pedagogical content knowledge (PCK) in physics in two institutions in England and Finland, using a practical physics activity and questionnaire. Teaching of physics activities was rated unpopular both in Finland and England, although English students…

  17. Antioxidant activity, phenolic and anthocyanin contents of various rhubarb (Rheum-spp.) varieties

    USDA-ARS?s Scientific Manuscript database

    Antioxidant activity (ABTS assay), total phenolics, and total anthocyanins were determined in the petioles of fifteen rhubarb (Rheum spp.) varieties. Antioxidant activity ranged from 491 ± 60 (Victoria 574/27) to 1820 'mol Trolox/g DW (Valentine). The phenolic content varied from 673 ± 41 (Loher Blu...

  18. Phytochrome Regulates Gibberellin Biosynthesis during Germination of Photoblastic Lettuce Seeds1

    PubMed Central

    Toyomasu, Tomonobu; Kawaide, Hiroshi; Mitsuhashi, Wataru; Inoue, Yasunori; Kamiya, Yuji

    1998-01-01

    Germination of lettuce (Lactuca sativa L.) seed is regulated by phytochrome. The requirement for red light is circumvented by the application of gibberellin (GA). We have previously shown that the endogenous content of GA1, the main bioactive GA in lettuce seeds, increases after red-light treatment. To clarify which step of GA1 synthesis is regulated by phytochrome, cDNAs encoding GA 20-oxidases (Ls20ox1 and Ls20ox2, for L. sativa GA 20-oxidase) and 3β-hydroxylases (Ls3h1 and Ls3h2 for L. sativa GA 3β-hydroxylase) were isolated from lettuce seeds by reverse-transcription polymerase chain reaction. Functional analysis of recombinant proteins expressed in Escherichia coli confirmed that the Ls20ox and Ls3h encode GA 20-oxidases and 3β-hydroxylases, respectively. Northern-blot analysis showed that Ls3h1 expression was dramatically induced by red-light treatment within 2 h, and that this effect was canceled by a subsequent far-red-light treatment. Ls3h2 mRNA was not detected in seeds that had been allowed to imbibe under any light conditions. Expression of the two Ls20ox genes was induced by initial imbibition alone in the dark. The level of Ls20ox2 mRNA decreased after the red-light treatment, whereas that of Ls20ox1 was unaffected by light. These results suggest that red light promotes GA1 synthesis in lettuce seeds by inducing Ls3h1 expression via phytochrome action. PMID:9847128

  19. Auxin acts independently of DELLA proteins in regulating gibberellin levels.

    PubMed

    Reid, James B; Davidson, Sandra E; Ross, John J

    2011-03-01

    Shoot elongation is a vital process for plant development and productivity, in both ecological and economic contexts. Auxin and bioactive gibberellins (GAs), such as GA1, play critical roles in the control of elongation, along with environmental and endogenous factors, including other hormones such as the brassinosteroids. The effect of auxins, such as indole-3-acetic acid (IAA), is at least in part mediated by its effect on GA metabolism, since auxin up-regulates biosynthesis genes such as GA 3-oxidase and GA 20-oxidase and down regulates GA catabolism genes such as GA 2-oxidases, leading to elevated levels of bioactive GA 1. In our recent paper, we have provided evidence that this action of IAA is largely independent of DELLA proteins, the negative regulators of GA action, since the auxin effects are still present in the DELLA-deficient la cry-s genotype of pea. This was a crucial issue to resolve, since like auxin, the DELLAs also promote GA 1 synthesis and inhibit its deactivation. DELLAs are deactivated by GA, and thereby mediate a feedback system by which bioactive GA regulates its own level. However, our recent results, in themselves, do not show the generality of the auxin-GA relationship across species and phylogenetic groups or across different tissue types and responses. Further, they do not touch on the ecological benefits of the auxin-GA interaction. These issues are discussed below as well as the need for the development of suitable experimental systems to allow this process to be examined.

  20. Calcium and gibberellin-induced elongation of lettuce hypocotyl sections.

    PubMed

    Moll, C; Jones, R L

    1981-08-01

    The relationship between calcium ions and gibberellic acid (GA3)-induced growth in the excised hypocotyl of lettuce (Lactuca sativa L.) was investigated. The short-term kinetics of growth responses were measured using a linear displacement transducer. Test solutions were added either as drops to the filter paper on which the hypocotyl stood ("non-flow-past") or by switching solution flowing past the base of hypocotyl ("flow-past"), resulting in differences in growth behavior. Drops of CaCl2 added at a high concentration (10 mM) inhibited growth within a few minutes. This inhibition was reversed by ethylenediaminetetraacetic acid (EDTA). Drops of EDTA or ethyleneglycol-bis(2-aminoethylether)-tetraacetic acid caused a rapid increase in growth rate. Growth induced by EDTA was not further promoted by GA3. A continuous H2O flow resulted in growth rates comparable to those in response to GA3. Addition of CaCl2 to the flow-past medium inhibited growth and this inhibition was reversed by a decrease in CaCl2 concentration. The growth rate was found to be a function of CaCl2 concentration. When a constant CaCl2 concentration was maintained by the flow-past medium, a shift in pH from 5.5 to 4.25 had no obvious effect on hypocotyl elongation. Gibberellic acid was found to reverse the inhibitory effect of CaCl2, causing an increase in growth rate similar to that found previously when GA3 was added to hypocotyls grown in H2O under non-flow-past conditions. We propose that gibberellin controls extension growth in lettuce hypocotyl sections by regulating the uptake of Ca(2+) by the hypocotyl cells.

  1. Phytochemical Contents and Antioxidant and Antiproliferative Activities of Selected Black and White Sesame Seeds.

    PubMed

    Zhou, Lin; Lin, Xiaohui; Abbasi, Arshad Mehmood; Zheng, Bisheng

    2016-01-01

    Sesame (Sesamum indicum L.) seeds are popular nutritional food but with limited knowledge about their antioxidant and antiproliferative activities of various varieties. Phytochemical profiles and antioxidant and antiproliferative activities of six varieties of sesame (Sesamum indicum L.) seeds were studied. Fenheizhi3 (black) cultivar exhibited the maximum contents of total phenolics and lignans and values of total oxygen radical absorbance capacity (ORAC) and antiproliferative activity (EC50) against HepG2 cells. Bound ORAC values showed strong associations with bound phenolics contents (r = 0.976, p < 0.01); in bound phenolic extracts, EC50 values showed strong negative associations with phenolic contents (r = -0.869, p < 0.05) and ORAC values (r = -0.918, p < 0.01). Moreover, the contents of free phenolics were higher than that of the bound phenolics, and the three black sesame seeds generally depicted higher total phenolics compared to the three white varieties. The antioxidant (ORAC values) and antiproliferation activities of six sesame seeds were both associated with contents of bound phenolics (r > 0.8, p < 0.05). Interestingly, nonlignan components in bound phenolics contributed to the antioxidant and antiproliferative activities. This study suggested that Fenheizhi3 variety is superior to the other five varieties as antioxidant supplements.

  2. Effect of polyphenols on calcium content and alkaline phosphatase activity in rat femoral tissues in vitro.

    PubMed

    Yamaguchi, M; Jie, Z

    2001-12-01

    The effect of various polyphenols on calcium content and alkaline phosphatase activity in the femoral-diaphyseal and -metaphyseal tissues of young rats in vitro was investigated. Bone tissues were cultured for 24 h in serum-free Dulbecco's modified Eagle's medium containing either vehicle or various polyphenols (10(-7) - 10(-4) M). The presence of genistein (10(-6) - 10(-4) M) caused a significant increase in calcium content and alkaline phosphatase activity in the femoral-diaphyseal and -metaphyseal tissues. Resveratrol (10(-4) m) decreased metaphyseal calcium content significantly, and it (10(-6) - 10(-4) M) had a significant inhibitory effect on diaphyseal enzyme activity. Epigallocatechin gallate (EGCg; 10(-4) M) significantly inhibited alkaline phosphatase activity in the diaphyseal and metaphyseal tissues. EGCg (10(-7) - 10(-4) M) had no effect on bone calcium content. Meanwhile, glycitein, quercetin, or catechin in the range of 10(-7) to 10(-4) ml did not have an effect on calcium content and alkaline phosphatase activity in the femoral-diaphyseal and -metaphyseal tissues. The present study suggests that a phytoestrogen genistein has a unique anabolic effect on bone calcification in vitro.

  3. Phytochemical Contents and Antioxidant and Antiproliferative Activities of Selected Black and White Sesame Seeds

    PubMed Central

    Abbasi, Arshad Mehmood; Zheng, Bisheng

    2016-01-01

    Sesame (Sesamum indicum L.) seeds are popular nutritional food but with limited knowledge about their antioxidant and antiproliferative activities of various varieties. Phytochemical profiles and antioxidant and antiproliferative activities of six varieties of sesame (Sesamum indicum L.) seeds were studied. Fenheizhi3 (black) cultivar exhibited the maximum contents of total phenolics and lignans and values of total oxygen radical absorbance capacity (ORAC) and antiproliferative activity (EC50) against HepG2 cells. Bound ORAC values showed strong associations with bound phenolics contents (r = 0.976, p < 0.01); in bound phenolic extracts, EC50 values showed strong negative associations with phenolic contents (r = −0.869, p < 0.05) and ORAC values (r = −0.918, p < 0.01). Moreover, the contents of free phenolics were higher than that of the bound phenolics, and the three black sesame seeds generally depicted higher total phenolics compared to the three white varieties. The antioxidant (ORAC values) and antiproliferation activities of six sesame seeds were both associated with contents of bound phenolics (r > 0.8, p < 0.05). Interestingly, nonlignan components in bound phenolics contributed to the antioxidant and antiproliferative activities. This study suggested that Fenheizhi3 variety is superior to the other five varieties as antioxidant supplements. PMID:27597975

  4. Water activity of poultry litter: Relationship to moisture content during a grow-out.

    PubMed

    Dunlop, Mark W; McAuley, Jim; Blackall, Patrick J; Stuetz, Richard M

    2016-05-01

    Poultry grown on litter floors are in contact with their own waste products. The waste material needs to be carefully managed to reduce food safety risks and to provide conditions that are comfortable and safe for the birds. Water activity (Aw) is an important thermodynamic property that has been shown to be more closely related to microbial, chemical and physical properties of natural products than moisture content. In poultry litter, Aw is relevant for understanding microbial activity; litter handling and rheological properties; and relationships between in-shed relative humidity and litter moisture content. We measured the Aw of poultry litter collected throughout a meat chicken grow-out (from fresh pine shavings bedding material to day 52) and over a range of litter moisture content (10-60%). The Aw increased non-linearly from 0.71 to 1.0, and reached a value of 0.95 when litter moisture content was only 22-33%. Accumulation of manure during the grow-out reduced Aw for the same moisture content. These results are relevant for making decisions regarding litter re-use in multiple grow-outs as well as setting targets for litter moisture content to minimise odour, microbial risks and to ensure necessary litter physical conditions are maintained during a grow-out. Methods to predict Aw in poultry litter from moisture content are proposed. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  5. Physical activity and exercise promotion and prescription in undergraduate physiotherapy education: content analysis of Irish curricula.

    PubMed

    O'Donoghue, Grainne; Doody, Catherine; Cusack, Tara

    2011-06-01

    Overwhelming evidence shows that physical activity and exercise promotion and prescription are effective in preventing and managing numerous chronic conditions. With physiotherapists commonly referred to as 'exercise prescription experts', an in-depth knowledge of exercise promotion and prescription is assumed. However, to date, no information exists about what is or should be included in terms of undergraduate physiotherapy physical activity and exercise education, nor whether the content prepares graduates to be exercise experts for contemporary practice. To provide an accurate, contemporary picture of physical activity and exercise promotion and prescription content within Irish undergraduate physiotherapy curricula. Content analysis was used to explore physical activity and exercise inclusion within four of the five programmes in Ireland. Seven categories were generated. Frequency analysis for each category was used to provide a guide to the extensiveness of physical activity and exercise promotion and prescription content. All curricula included varying quantities of basic exercise science and exercise testing and prescription. Physical activity and exercise promotion and prescription for conditions routinely referred to physiotherapy, such as cardio respiratory disease, were well represented. Three key areas were identified as being absent or needing further emphasis: physical activity/exercise for public health, strategies for changing physical activity behaviour, and physical activity/exercise for lifestyle-related diseases. Results indicate a strong need for re-evaluation of physical activity and exercise education in Irish physiotherapy curricula. There is a lack of explicit exercise content in relation to public health and lifestyle-related disease. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  6. Diaphragm dysfunction in heart failure is accompanied by increases in neutral sphingomyelinase activity and ceramide content.

    PubMed

    Empinado, Hyacinth M; Deevska, Gergana M; Nikolova-Karakashian, Mariana; Yoo, Jeung-Ki; Christou, Demetra D; Ferreira, Leonardo F

    2014-05-01

    Chronic heart failure (CHF) causes inspiratory (diaphragm) muscle weakness and fatigue that contributes to dyspnoea and limited physical capacity in patients. However, the mechanisms that lead to diaphragm dysfunction in CHF remain poorly understood. Cytokines and angiotensin II are elevated in CHF and stimulate the activity of the enzyme sphingomyelinase (SMase) and accumulation of its reaction product ceramide. In the diaphragm, SMase or ceramide exposure in vitro causes weakness and fatigue. Thus, elevated SMase activity and ceramide content have been proposed as mediators of diaphragm dysfunction in CHF. In the present study, we tested the hypotheses that diaphragm dysfunction was accompanied by increases in diaphragm SMase activity and ceramide content. Myocardial infarction was used to induce CHF in rats. We measured diaphragm isometric force, SMase activity by high-performance liquid chromatography, and ceramide subspecies and total ceramide using mass spectrometry. Diaphragm force was depressed and fatigue accelerated by CHF. Diaphragm neutral SMase activity was increased by 20% in CHF, while acid SMase activity was unchanged. We also found that CHF increased the content of C18 -, C20 -, and C24 -ceramide subspecies and total ceramide. Downstream of ceramide degradation, diaphragm sphingosine was unchanged, and sphingosine-1-phosphate level was increased in CHF. Our major novel finding was that diaphragm dysfunction in CHF rats was accompanied by higher diaphragm neutral SMase activity, which is expected to cause the observed increase in diaphragm ceramide content. © 2014 The Authors. European Journal of Heart Failure © 2014 European Society of Cardiology.

  7. Water content or water activity: what rules crispy behavior in bread crust?

    PubMed

    van Nieuwenhuijzen, N H; Primo-Martín, C; Meinders, M B J; Tromp, R H; Hamer, R J; van Vliet, T

    2008-08-13

    A dry crust loses its crispness when water migrates into the crust. It is not clear if it is the amount of water absorbed or the water activity ( a w) that leads to a loss of crispness. The hysteresis effect observed when recording a water sorption isotherm allowed us to study the effects of a w and moisture content separately. All experiments were carried out on model bread crusts made from Soissons bread flour. The effect of water content and water activity on the glass transition of model bread crusts was studied in detail using two complimentary techniques: phase transition analysis (PTA) and nuclear magnetic resonance (NMR). The results were compared with sensory data and results from a puncture test, which provided data on acoustic emission and fracture mechanics during breaking of the crusts. The water content of the crust was found to be decisive for the transition point as measured by PTA and NMR. However, both water content and water activity had an effect on perceived crispness and number of force and sound peaks. From this may be concluded that the distribution of the water in the samples with a history of high water content is more inhomogeneous, which results in crispy and less crispy regions, thus making them overall more crispy than samples with the same water content but higher a w.

  8. Effect of Cu content on the antibacterial activity of titanium-copper sintered alloys.

    PubMed

    Liu, Jie; Li, Fangbing; Liu, Cong; Wang, Hongying; Ren, Baorui; Yang, Ke; Zhang, Erlin

    2014-02-01

    The phase constitution and the microstructure Ti-x Cu (x=2, 5, 10 and 25 wt.%) sintered alloys were investigated by XRD and SEM and the antibacterial activity was assessed in order to investigate the effect of the Cu content on the antibacterial activity. The results have shown that Ti2Cu was synthesized as a main secondary phase in all Ti-Cu alloys while Cu-rich phase was formed in the alloys with 5 wt.% or more copper. Antibacterial tests have showed that the Cu content influences the antibacterial rate seriously and only the alloys with 5 wt.% or high Cu have a strong and stable antibacterial rate, which indicates that the Cu content in Ti-Cu alloys must be at least 5 wt.% to obtain strong and stable antibacterial property. The Cu content also influenced the Cu ion release behavior. High Cu ion release concentration and high Cu ion release rate were observed for Ti-Cu alloys with high Cu content. It was concluded that the Cu content affects the Cu existence and the Cu ion release behavior, which in turn influences the antibacterial property. It was thought that the Cu-rich phase should play an important role in the strong antibacterial activity. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Gibberellin production and plant growth promotion from pure cultures of Cladosporium sp. MH-6 isolated from cucumber (Cucumis sativus L.).

    PubMed

    Hamayun, Muhammad; Khan, Sumera Afzal; Khan, Abdul Latif; Rehman, Gauhar; Kim, Youn-Ha; Iqbal, Ilyas; Hussain, Javid; Sohn, Eun-Young; Lee, In-Jung

    2010-01-01

    Gibberellin (GA) production by soil fungi has received little attention, although substantial work has been carried out on other aspects of plant growth promoting fungi (PGPF). In our studies we investigated GA production and growth-promoting capacity of a novel fungal strain isolated from the roots of soil-grown cucumber. Pure cultures of 19 endophytic fungi were tested for shoot length promotion of Waito-C rice to identify the GA production capacity of these fungal isolates. Isolate MH-6 significantly increased shoot length (12.9 cm) of Waito-C, in comparison to control treatments. Bioassay with culture filtrate (CF) of MH-6 also significantly promoted growth attributes of cucumber plants. Analysis of MH-6 CF showed the presence of physiologically active (GA1, 1.97 ng/mL; GA3, 5.18 ng/mL; GA4, 13.35 ng/mL and GA7, 2.4 ng/ mL) in conjunction with physiologically inactive (GA9 [0.69 ng/mL], GA12 [0.24 ng/mL], GA15 [0.68 ng/ mL, GA19 [1.94 ng/mL and GA20 [0.78 ng/mL]) gibberellins. The CF of MH-6 produced greater amounts of GA3, GA4, GA7 and GA19 than wild type Fusarium fujikuroi, a fungus known for high production of GA. The fungal isolate MH-6 was identified as a new strain of Cladosporium sp. on the basis of sequence homology (99%) and phylogenetic analysis of 18S rDNA sequence.

  10. Polyphenolic Contents and Antioxidant Activities of Underutilized Grape (Vitis vinifera L.) Pomace Extracts.

    PubMed

    Kabir, Faisal; Sultana, Mosammad Shahin; Kurnianta, Heri

    2015-09-01

    Grape pomace is an abundant source of underutilized winery by-products. Polyphenols were extracted from grape pomace using cellulase and gluco-amylase enzymes. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteu's assays were used to measure antioxidant activity and total polyphenolic contents. Both cellulase, and gluco-amylase digested grape pomace showed efficient radical scavenging activity. In addition, the total polyphenolic contents of cellulase digested grape pomace showed lower concentrations were effective compared to higher concentrations, whereas gluco-amylase enzyme did not show remarkable variations. The DPPH radical scavenging activity and total polyphenolic contents were significantly higher in the cellulase digested grape pomace compared to the gluco-amylase digested and the not digested grape pomace. It is notable that enzymatic digestions were efficient for extracting polyphenols from grape pomace. The underutilized grape pomace polyphenols can be further used for food safety as a natural antioxidant.

  11. Anti-Inflammatory and Antioxidant Activities of Salvia fruticosa: An HPLC Determination of Phenolic Contents.

    PubMed

    Boukhary, Rima; Raafat, Karim; Ghoneim, Asser I; Aboul-Ela, Maha; El-Lakany, Abdalla

    2016-01-01

    Objectives. Salvia fruticosa Mill. (S. fruticosa) is widely used in folk medicine. Accordingly, the present study was designed to evaluate the antioxidant and anti-inflammatory activities of S. fruticosa, and to determine the phenolic constituents of its extracts. Methods. The antioxidant activity was determined using 2,2-diphenylpicrylhydrazyl assay. Total phenolic contents were estimated using Folin-Ciocalteu reagent, and high-performance liquid chromatography was performed to identify phenolic constituents. To evaluate the anti-inflammatory activity, carrageenan-induced mouse paw edema was determined plethysmographically. Key Findings. Different plant extracts demonstrated strong radical scavenging activity, where the ethyl acetate extract had the highest value in the roots and the lowest in the aerial parts. This antioxidant activity was correlated to the total phenolic content of different extracts, where rutin and luteolin were the most abundant constituents. Interestingly, both the roots and aerial parts revealed a significant anti-inflammatory activity comparable to diclofenac. Conclusions. This study is the first to demonstrate pharmacologic evidence of the potential anti-inflammatory activity of S. fruticosa. This activity may partly be due to the radical scavenging effects of its polyphenolic contents. These findings warrant the popular use of the East Mediterranean sage and highlight the potential of its active constituents in the development of new anti-inflammatory drugs.

  12. ACTIVITY AND ISOZYME CONTENT OF LACTATE DEHYDROGENASE UNDER LONG-TERM ORAL TAURINE ADMINISTRATION TO RATS.

    PubMed

    Ostapiv, R D; Humenyuk, S L; Manko, V V

    2015-01-01

    The effect of long-term oral taurine administration to rats on activity of lactate dehydrogenase (LDH), its isozyme content and activity in the whole blood, liver, thigh muscle, brain and testes tissues were studied in the present work. For this purpose male Wistar rats with body weight 190-220 g were randomly divided into three groups, they were orally administered drinking water (control group) or taurine solution 40 and 100 mg per kg of body weight ( groups I and II, respectively). The total lactate dehydrogenase activity was measured spectrophotometrically, the percentage content of isozymes was determined by electrophoresis in 7.5% poliacrylamide gel withfurther staining according to J. Garbus. It was found that the total lactate dehydrogenase activity increased in all studied tissues. In testes of animals of both groups and in brain of group I animals, the total percentage contents of isozymes that are responsible for lactate production (LDH4+LDH5) increased. In liver of animals of both groups and in whole blood of group II animals, the total percentage content of isozymes that produce pyruvate (LDH1+LDH2) increased. In thigh muscle of both groups and in brain of group II animals the balance between LDH1+LDH2 and LDH4+LDH5 content did not differ from control values, though total lactate dehydrogenase activity was significantly higher, than that in the control group. Thus, the increase in the lactate dehydrogenase activity under long-term oral taurine administration in different rat tissues was found to be tissue- and dose-dependent and was caused by the increase in the content of different isozymes. Such increase in group I animals might be explained by adaptive mechanisms to hypoxia caused by high doses of taurine. For group II animals high doses of taurine were toxic and directly affected metabolic processes in the animal bodies.

  13. Biochemical characterization of three hamster melanoma variants--I. Tyrosinase activity and melanin content.

    PubMed

    Słomiński, A; Scisłowski, P W; Bomirski, A

    1984-01-01

    Tyrosinase activity in the soluble fraction of the cells and melanin content in the whole cells of the black-melanotic (Ma), brown-melanotic (MI) and amelanotic (Ab) hamster melanomas were studied. The activity of the soluble tyrosinase was highest in MI lower in Ma, and very low in Ab melanoma. Melanin content was greatest in the Ma, lower in MI, and none in Ab melanoma. Acrylamide gel electrophoretic pattern of the soluble tyrosinase consisted of 2 bands in Ma and MI melanomas, and of 1 band in Ab melanoma.

  14. Auxin-induced nitric oxide, cGMP and gibberellins were involved in the gravitropism

    NASA Astrophysics Data System (ADS)

    Cai, Weiming; Hu, Liwei; Hu, Xiangyang; Cui, Dayong; Cai, Weiming

    Gravitropism is the asymmetric growth or curvature of plant organs in response to gravistimulation. There is a complex signal transduction cascade which involved in the differential growth of plants in response to changes in the gravity vector. The role of auxin in gravitropism has been demonstrated by many experiments, but little is known regarding the molecular details of such effects. In our studies before, mediation of the gravitropic bending of soybean roots and rice leaf sheath bases by nitric oxide, cGMP and gibberellins, are induced by auxin. The asymmetrical distribution of nitric oxide, cGMP and gibberellins resulted from the asymmetrical synthesis of them in bending sites. In soybean roots, inhibitions of NO and cGMP synthesis reduced differential NO and cGMP accumulation respectively, which both of these effects can lead to the reduction of gravitropic bending. Gibberellin-induced OsXET, OsEXPA4 and OsRWC3 were also found involved in the gravitropic bending. These data indicated that auxin-induced nitric oxide, cGMP and gibberellins were involved in the gravitropism. More experiments need to prove the more detailed mechanism of them.

  15. Lifting DELLA repression of Arabidopsis seed germination by nonproteolytic gibberellin signaling

    USDA-ARS?s Scientific Manuscript database

    DELLA repression of Arabidopsis seed germination can be lifted through the ubiquitin-proteasome pathway and proteolysis-independent GA signaling. GA-binding to the GID1 (GIBBERELLIN-INSENSITIVE DWARF1) GA receptors stimulates GID1-GA-DELLA complex formation which in turn triggers DELLA protein ubiq...

  16. Gibberellin hormone signal perception: down-regulating DELLA repressors of plant growth and development

    USDA-ARS?s Scientific Manuscript database

    The gibberellin (GA) hormone signal is perceived by a receptor with homology to hormone sensitive lipases, GID1 (GA-INSENSITIVE DWARF1). This leads to GA-stimulated responses including stem elongation, seed germination, and the transition to flowering. GA-binding enables GID1 to interact with and ...

  17. Brassinosteroid and Gibberellin control of seedling traits in maize (Zea mays L.)

    USDA-ARS?s Scientific Manuscript database

    Brassinosteroids (BRs) and gibberellins (GAs) are two major plant hormones regulating various plant developmental processes. In maize, BRs and GAs have been shown to regulate field traits such as plant height and sex determination. This study used 207 doubled haploid maize lines and measured respons...

  18. Characterization of grape Gibberellin Insensitive 1 mutant alleles in transgenic Arabidopsis

    USDA-ARS?s Scientific Manuscript database

    We generated a dozen of different mutations in the grape Gibberellin Insensitive or GAI sequence, transformed them into Arabidopsis under the control of 35S, Arabidopsis or grape GAI promoter, and evaluated the impact of these mutant alleles on plant growth and development. These GAI sequence varian...

  19. Gibberellin biosynthesis in bacteria: separate ent-copalyl diphosphate and ent-kaurene synthases in Bradyrhizobium japonicum.

    PubMed

    Morrone, Dana; Chambers, Jacob; Lowry, Luke; Kim, Gunjune; Anterola, Aldwin; Bender, Kelly; Peters, Reuben J

    2009-01-22

    Gibberellins are ent-kaurene-derived diterpenoid phytohormones produced by plants, fungi, and bacteria. The distinct gibberellin biosynthetic pathways in plants and fungi are known, but not that in bacteria. Plants typically use two diterpene synthases to form ent-kaurene, while fungi use only a single bifunctional diterpene synthase. We demonstrate here that Bradyrhizobium japonicum encodes separate ent-copalyl diphosphate and ent-kaurene synthases. These are found in an operon whose enzymatic composition indicates that gibberellin biosynthesis in bacteria represents a third independently assembled pathway relative to plants and fungi. Nevertheless, sequence comparisons also suggest potential homology between diterpene synthases from bacteria, plants, and fungi.

  20. Functional Analysis of SPINDLY in Gibberellin Signaling in Arabidopsis1[C][W][OA

    PubMed Central

    Silverstone, Aron L.; Tseng, Tong-Seung; Swain, Stephen M.; Dill, Alyssa; Jeong, Sun Yong; Olszewski, Neil E.; Sun, Tai-ping

    2007-01-01

    The Arabidopsis (Arabidopsis thaliana) SPINDLY (SPY) protein negatively regulates the gibberellin (GA) signaling pathway. SPY is an O-linked N-acetylglucosamine (GlcNAc) transferase (OGT) with a protein-protein interaction domain consisting of 10 tetratricopeptide repeats (TPR). OGTs add a GlcNAc monosaccharide to serine/threonine residues of nuclear and cytosolic proteins. Determination of the molecular defects in 14 new spy alleles reveals that these mutations cluster in three TPRs and the C-terminal catalytic region. Phenotypic characterization of 12 spy alleles indicates that TPRs 6, 8, and 9 and the catalytic domain are crucial for GA-regulated stem elongation, floral induction, and fertility. TPRs 8 and 9 and the catalytic region are also important for modulating trichome morphology and inflorescence phyllotaxy. Consistent with a role for SPY in embryo development, several alleles affect seedling cotyledon number. These results suggest that three of the TPRs and the OGT activity in SPY are required for its function in GA signal transduction. We also examined the effect of spy mutations on another negative regulator of GA signaling, REPRESSOR OF ga1-3 (RGA). The DELLA motif in RGA is essential for GA-induced proteolysis of RGA, and deletion of this motif (as in rga-Δ17) causes a GA-insensitive dwarf phenotype. Here, we demonstrate that spy partially suppresses the rga-Δ17 phenotype but does not reduce rga-Δ17 or RGA protein levels or alter RGA nuclear localization. We propose that SPY may function as a negative regulator of GA response by increasing the activity of RGA, and presumably other DELLA proteins, by GlcNAc modification. PMID:17142481

  1. Roles of Gibberellins and Abscisic Acid in Regulating Germination of Suaeda salsa Dimorphic Seeds Under Salt Stress

    PubMed Central

    Li, Weiqiang; Yamaguchi, Shinjiro; Khan, M. Ajmal; An, Ping; Liu, Xiaojing; Tran, Lam-Son P.

    2016-01-01

    Seed heteromorphism observed in many halophytes is an adaptive phenomenon toward high salinity. However, the relationship between heteromorphic seed germination and germination-related hormones under salt stress remains elusive. To gain an insight into this relationship, the roles of gibberellins (GAs) and abscisic acid (ABA) in regulating germination of Suaeda salsa dimorphic brown and black seeds under salinity were elucidated by studying the kinetics of the two hormones during germination of the two seed types with or without salinity treatment. Morphological analysis suggested that brown and black are in different development stage. The content of ABA was higher in dry brown than in black seeds, which gradually decreased after imbibition in water and salt solutions. Salt stress induced ABA accumulation in both germinating seed types, with higher induction effect on black than brown seeds. Black seeds showed lower germination percentage than brown seeds under both water and salt stress, which might be attributed to their higher ABA sensitivity rather than the difference in ABA content between black and brown seeds. Bioactive GA4 and its biosynthetic precursors showed higher levels in brown than in black seeds, whereas deactivated GAs showed higher content in black than brown seeds in dry or in germinating water or salt solutions. High salinity inhibited seed germination through decreasing the levels of GA4 in both seeds, and the inhibited effect of salt stress on GA4 level of black seeds was more profound than that of brown seeds. Taken together higher GA4 content, and lower ABA sensitivity contributed to the higher germination percentage of brown seeds than black seeds in water and salinity; increased ABA content and sensitivity, and decreased GA4 content by salinity were more profound in black than brown seeds, which contributed to lower germination of black seeds than brown seeds in salinity. The differential regulation of ABA and GA homeostases by salt

  2. Roles of Gibberellins and Abscisic Acid in Regulating Germination of Suaeda salsa Dimorphic Seeds Under Salt Stress.

    PubMed

    Li, Weiqiang; Yamaguchi, Shinjiro; Khan, M Ajmal; An, Ping; Liu, Xiaojing; Tran, Lam-Son P

    2015-01-01

    Seed heteromorphism observed in many halophytes is an adaptive phenomenon toward high salinity. However, the relationship between heteromorphic seed germination and germination-related hormones under salt stress remains elusive. To gain an insight into this relationship, the roles of gibberellins (GAs) and abscisic acid (ABA) in regulating germination of Suaeda salsa dimorphic brown and black seeds under salinity were elucidated by studying the kinetics of the two hormones during germination of the two seed types with or without salinity treatment. Morphological analysis suggested that brown and black are in different development stage. The content of ABA was higher in dry brown than in black seeds, which gradually decreased after imbibition in water and salt solutions. Salt stress induced ABA accumulation in both germinating seed types, with higher induction effect on black than brown seeds. Black seeds showed lower germination percentage than brown seeds under both water and salt stress, which might be attributed to their higher ABA sensitivity rather than the difference in ABA content between black and brown seeds. Bioactive GA4 and its biosynthetic precursors showed higher levels in brown than in black seeds, whereas deactivated GAs showed higher content in black than brown seeds in dry or in germinating water or salt solutions. High salinity inhibited seed germination through decreasing the levels of GA4 in both seeds, and the inhibited effect of salt stress on GA4 level of black seeds was more profound than that of brown seeds. Taken together higher GA4 content, and lower ABA sensitivity contributed to the higher germination percentage of brown seeds than black seeds in water and salinity; increased ABA content and sensitivity, and decreased GA4 content by salinity were more profound in black than brown seeds, which contributed to lower germination of black seeds than brown seeds in salinity. The differential regulation of ABA and GA homeostases by salt

  3. Antioxidant Activities and Total Phenolic Content of Aqueous Extract of Pleurotus ostreatus (Cultivated Oyster Mushroom).

    PubMed

    Yim, H S; Chye, F Y; Tan, C T; Ng, Y C; Ho, C W

    2010-08-01

    Pleurotus ostreatus better known as oyster mushroom is widely cultivated and consumed as food in Malaysia. The present study aims to assess the antioxidative potential and total phenolic content of P. ostreatus aqueous extract. The antioxidant activities were evaluated against DPPH and ABTS radical-scavenging activity, ferric-reducing antioxidant power (FRAP) and β-carotene-linoleate bleaching assay, and the Folin-Ciocalteu method for total phenolic content (TPC). The DPPH and ABTS radical-scavenging activity was found to be 63.20% and 87.29% respectively; antioxidant activity using FRAP at 1.45 mM FE/100g and β-carotenelinoleate bleaching assay was 83.51%, while the TPC was found to be 798.55 mg GAE/100g. These antioxidant activities were compared to synthetic antioxidant, BHA and ascorbic acid. Ascorbic acid showed highest scavenging effects on DPPH and ABTS radical, followed by P. ostreatus and BHA (at maximum safety limit). The ferric reducing power of P. ostreatus was significantly higher than BHA and ascorbic acid. The antioxidant activity as assessed in β-carotene-linoleate bleaching assay was found to be higher in BHA compared to P. ostreatus. The aqueous extract of P. ostreatus was found to respond differently in antioxidant assays. The antioxidative activity of the aqueous extract of P. ostreatus correlated with its total phenolic content. Generally, the antioxidant activities of P. ostreatus' aqueous extract are comparable to that of BHA and ascorbic acid to a certain extent.

  4. Labeled Content of Two Furanocoumarins in Dietary Supplements Correlates with neither Actual Content nor CYP3A Inhibitory Activity

    PubMed Central

    VanderMolen, Karen M.; Ainslie, Garrett R.; Paine, Mary F.; Oberlies, Nicholas H.

    2014-01-01

    Dietary supplements are a multi-billion dollar business, with yearly profit increases. Allegedly safe, these supplements are marketed to a variety of niches, encompassing claims from immune support to weight loss. Six sports nutrition supplements were acquired that were labeled to contain the furanocoumarin(s) bergamottin and/or 6′,7′-dihydroxybergamottin (DHB), both of which are potent irreversible inhibitors of the prominent drug metabolizing enzyme cytochrome P450 3A (CYP3A). Both furanocoumarins are typically present in grapefruit juice, which has been shown to inhibit intestinal CYP3A, perpetrating an increase in the systemic exposure of certain concomitant ‘victim’ drugs. The acquired supplements were analyzed using ultra-performance liquid chromatography coupled to both a photodiode array (PDA) detector and a triple quadrupole mass spectrometer (MS). Contrary to the product labeling, four of the supplements contained no detectable quantities of either furanocoumarin (LOD 0.060 μg/capsule), while two of the supplements contained minimal amounts (one contained 12.13 (± 0.23) μg bergamottin and 65.51 (± 0.64) μg DHB per capsule; the other contained 2.705 (± 0.069) μg bergamottin per capsule and no detectable quantities of DHB). A CYP3A inhibition bioassay was used to assess whether the actual content of the furanocoumarins correlated with CYP3A inhibitory activity. Despite the low amounts of bergamottin and DHB, CYP3A inhibition by the supplements was greater than could be accounted for by the two furanocoumarins. The additional activity suggests the presence of other potent or highly abundant CYP3A inhibitors. PMID:24951959

  5. Conventional, organic and biodynamic farming: differences in polyphenol content and antioxidant activity of Batavia lettuce.

    PubMed

    Heimler, Daniela; Vignolini, Pamela; Arfaioli, Paola; Isolani, Laura; Romani, Annalisa

    2012-02-01

    Lactuca sativa L. ssp. acephala L., cv. Batavia red Mohican plants were cultivated under intensive conventional, organic and biodynamic farming and were analyzed for their polyphenol content and antiradical activity in order to demonstrate the influence of farming on yield, polyphenol content and antiradical activity. The yield of plants from conventional farming was the highest (2.89 kg m⁻²), while polyphenol content, measured by spectrophotometry, of these plants was lower at P < 0.05 (1.36 mg g⁻¹) than the content of plants from organic and biodynamic farming (1.74 and 1.85 mg g⁻¹, respectively). The antiradical activity, measured by DPPH · assay, was positively correlated to flavonoid and hydroxycinnamic acid contents. Flavonoid, hydroxycinnamic acid and anthocyan patterns were not affected by the type of cultivation, while quantitative differences were demonstrated and some differences were found between conventional farming and organic or biodynamic farming. The yield of conventionally grown salads was the highest. Copyright © 2011 Society of Chemical Industry.

  6. Gibberellin is required for the formation of tension wood and stem gravitropism in Acacia mangium seedlings

    PubMed Central

    Nugroho, Widyanto Dwi; Yamagishi, Yusuke; Nakaba, Satoshi; Fukuhara, Shiori; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

    2012-01-01

    Background and Aims Angiosperm trees generally form tension wood on the upper sides of leaning stems. The formation of tension wood is an important response to gravitational stimulus. Gibberellin appears to be involved in the differentiation of secondary xylem, but it remains unclear whether gibberellin plays a key role in the formation of tension wood and plant gravitropism. Therefore, a study was designed to investigate the effects of gibberellin and of inhibitors of the synthesis of gibberellin, namely paclobutrazole and uniconazole-P, on the formation of tension wood and negative stem gravitropism in Acacia mangium seedlings. Methods Gibberellic acid (GA3), paclobutrazole and uniconazole-P were applied to seedlings via the soil in which they were growing. Distilled water was applied similarly as a control. Three days after such treatment, seedlings were tilted at an angle of 45° from the vertical, and samples of stems were collected for analysis 2 weeks, 2 months and 6 months after tilting. The effects of treatments on the stem recovery degree (Rº) were analysed as an index of the negative gravitropism of seedlings, together the width of the region of tension wood in the upper part of inclined stems. Key Results It was found that GA3 stimulated the negative gravitropism of tilted seedling stems of A. mangium, while paclobutrazole and uniconazole-P inhibited recovery to vertical growth. Moreover, GA3 stimulated the formation of tension wood in tilted A. mangium seedlings, while paclobutrazole and uniconazole-P strongly suppressed the formation of tension wood, as assessed 2 weeks after tilting. Conclusions The results suggest that gibberellin plays an important role at the initial stages of formation of tension wood and in stem gravitropism in A. mangium seedlings in response to a gravitational stimulus. PMID:22843341

  7. Gibberellin is required for the formation of tension wood and stem gravitropism in Acacia mangium seedlings.

    PubMed

    Nugroho, Widyanto Dwi; Yamagishi, Yusuke; Nakaba, Satoshi; Fukuhara, Shiori; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

    2012-09-01

    Angiosperm trees generally form tension wood on the upper sides of leaning stems. The formation of tension wood is an important response to gravitational stimulus. Gibberellin appears to be involved in the differentiation of secondary xylem, but it remains unclear whether gibberellin plays a key role in the formation of tension wood and plant gravitropism. Therefore, a study was designed to investigate the effects of gibberellin and of inhibitors of the synthesis of gibberellin, namely paclobutrazole and uniconazole-P, on the formation of tension wood and negative stem gravitropism in Acacia mangium seedlings. Gibberellic acid (GA(3)), paclobutrazole and uniconazole-P were applied to seedlings via the soil in which they were growing. Distilled water was applied similarly as a control. Three days after such treatment, seedlings were tilted at an angle of 45° from the vertical, and samples of stems were collected for analysis 2 weeks, 2 months and 6 months after tilting. The effects of treatments on the stem recovery degree (Rº) were analysed as an index of the negative gravitropism of seedlings, together the width of the region of tension wood in the upper part of inclined stems. It was found that GA(3) stimulated the negative gravitropism of tilted seedling stems of A. mangium, while paclobutrazole and uniconazole-P inhibited recovery to vertical growth. Moreover, GA(3) stimulated the formation of tension wood in tilted A. mangium seedlings, while paclobutrazole and uniconazole-P strongly suppressed the formation of tension wood, as assessed 2 weeks after tilting. The results suggest that gibberellin plays an important role at the initial stages of formation of tension wood and in stem gravitropism in A. mangium seedlings in response to a gravitational stimulus.

  8. Gibberellin stimulates regrowth after defoliation of sheepgrass (Leymus chinensis) by regulating expression of fructan-related genes.

    PubMed

    Cai, Yueyue; Shao, Linhui; Li, Xiuqing; Liu, Gongshe; Chen, Shuangyan

    2016-09-01

    Gibberellins (GAs) affect forage growth and development; however, it is largely unknown how GAs regulate the metabolism of fructan (an important polysaccharide reserve in many cereals) and the regrowth of forage plants after defoliation. To explore the mechanism of the responses of defoliated sheepgrass [Leymus chinensis (Trin.) Tzvel] to GA, we sprayed defoliated sheepgrass with GA3 and/or paclobutrazol (PAC; an inhibitor of GA biosynthesis) and analyzed the growth characteristics, carbohydrate contents, and transcript levels of genes related to GA metabolism, GA signal transduction, and fructan metabolism. The results showed that spraying exogenous GA3 onto defoliated sheepgrass promoted leaf and internode elongation, while spraying with PAC inhibited leaf and internode elongation, compared with the control. Spraying GA3 onto defoliated sheepgrass also altered the fructan content by extending the period of fructan utilization. At the transcriptional level, exogenous GA3 increased the transcript levels of genes related to GA metabolism in the sheath. Taken together, our results suggest that exogenous GA3 stimulates the regrowth of defoliated sheepgrass regrowth by regulating GA and fructan-related genes, and by promoting endogenous GA synthesis, fructan metabolism, and signaling.

  9. Relationship among antioxidant activity, vasodilation capacity, and phenolic content of red wines.

    PubMed

    Burns, J; Gardner, P T; O'Neil, J; Crawford, S; Morecroft, I; McPhail, D B; Lister, C; Matthews, D; MacLean, M R; Lean, M E; Duthie, G G; Crozier, A

    2000-02-01

    The relationship among antioxidant activity, based on the electron-spin resonance determination of the reduction of Fremy's radical, vasodilation activity, and phenolic content was investigated in 16 red wines. The wines were selected to provide a range of origins, grape varieties, and vinification methods. Sensitive and selective HPLC methods were used for the analysis of the major phenolics in red wine: free and conjugated myricetin, quercetin, kaempferol, and isorhamnetin; (+)-catechin, (-)-epicatechin, gallic acid, p-coumaric acid, caffeic acid, caftaric acid, trans-resveratrol, cis-resveratrol, and trans-resveratrol glucoside. Total anthocyanins were measured using a colorimetric assay. The total phenolic content of the wines was determined according to the Folin-Ciocalteu colorimetric assay and also by the cumulative measurements obtained by HPLC. The 16 wines exhibited a wide range in the values of all parameters investigated. However, the total phenol contents, measured both by HPLC and colorimetrically, correlated very strongly with the antioxidant activity and vasodilation activity. In addition, the antioxidant activity was associated with gallic acid, total resveratrol, and total catechin. In contrast, only the total anthocyanins were correlated with vasodilation activity. The results demonstrate that the different phenolic profiles of wines can produce varying antioxidant and vasodilatant activities, which opens up the possibility that some red wines may provide enhanced health benefits for the consumer.

  10. Polyphenol content and antioxidant activity of California almonds depend on cultivar and harvest year ☆

    PubMed Central

    Bolling, Bradley W.; Dolnikowski, Gregory; Blumberg, Jeffrey B.; Chen, C.-Y. Oliver

    2014-01-01

    The polyphenol content and antioxidant activity of Nonpareil, Carmel, Butte, Sonora, Fritz, Mission, and Monterey almond cultivars harvested over three seasons in California were examined. LC–MS was employed to quantify 16 flavonoids and two phenolic acids in acidified methanol extracts of almond skins. The 3-year mean polyphenol content of cultivars ranged from 4.0 to 10.7 mg/100 g almonds. Isorhamnetin-3-O-rutinoside was the most abundant flavonoid, present at 28–49% of total polyphenols among cultivars. Almonds from 2006 and 2007 had 13% fewer polyphenols than 2005, but FRAP and total phenols were comparable. Cultivar, but not season, had a differential impact on individual polyphenol synthesis. Using the results of polyphenol, total phenol, and FRAP, multivariate analysis distinguished harvest years and most cultivars with 80% confidence. Flavonoid content and antioxidant activity of almonds may be more dependent on cultivar than on seasonal differences. PMID:25544797

  11. Endogenous Gibberellins and Shoot Growth and Development in Brassica napus.

    PubMed

    Rood, S B; Mandel, R; Pharis, R P

    1989-01-01

    Greenhouse-grown oilseed rape (Brassica napus, annual Canola variety ;Westar') plants were harvested at six dates from the vegetative phase until the early pod (silique)-fill/late flowering stage. Endogenous gibberellin (GA)-like substances were extracted from stems, purified, and chromatographed on silica gel partition columns prior to bioassay in serial dilution using the ;Tan-ginbozu' dwarf rice microdrop assay. The concentrations of total endogenous GA-like substances were low during vegetative stages (1 nanogram GA(3) equivalents/gram dry weight), and rose 300-fold by the time of floral initiation. After floral initiation the concentration of GA-like substances fell, then rose again during bolting to maximal levels during the early pod-fill stage (940 nanograms per gram dry weight). The qualitative profiles of GA-like substances varied across harvests, with higher proportions of a GA(1)-like substance at the early pod-fill stage. In a second study stems were similarly harvested at eight dates and the concentrations of endogenous GA(1), the principal bioactive native GA of oilseed rape, were determined by gas chromatography-selected ion monitoring using [17,17-(2)H]GA(1) as a quantitative internal standard. The concentration of GA(1) increased at about the time of floral initiation and then subsequently fell, thus confirming the pattern noted above for total GA-like substances. The exogenous application of paclobutrazol (PP333), a persistent triazole plant growth regulator (PGR) which blocks GA biosynthesis, or another triazole, triapenthenol (RSW0411), prevented flowering as well as bolting; plants remained at the vegetative rosette stage. These results imply a causal role for endogenous GA, in the control of bolting, which normally precedes anthesis. Further, the rise in the concentration of total endogenous GA-like substances, including GA(1), which was associated with floral initiation, and the prevention of visable floral development by the triazole PGRs

  12. Influence of heating on the polyphenolic content and antioxidant activity of grape seed flour.

    PubMed

    Ross, Carolyn Felicity; Hoye, Clifford; Fernandez-Plotka, Virginia Christina

    2011-08-01

    The production of grape seed flour (GSF) from a waste product generated during winemaking, is of interest in product development applications due to its potential health benefits. However, before GSF can used in baking as a source of additional antioxidants, research on its heat stability is required. The overall objective of this study was to assess changes in phenolic content and antioxidant activity of GSF during heating. Merlot GSF was heated at 5 temperatures (120 to 240 °C) for 0 to 90 min. At each time/temperature combination, total phenolic content (TPC), total flavanoid content (TFC), Trolox equivalent antioxidant capacity (TEAC), 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and ferric ion reducing antioxidant power (FRAP) of the extracts were determined. Specific polyphenolic compounds, including catechin, gallocatechin, epicatechin, and gallic acid were also measured. Results showed that when Merlot GSF was heated to ≥180 °C, significant decreases in the TPC and antioxidant activity, measured using FRAP, DPPH, and TEAC, were observed. Longer heating times also caused a reduction in antioxidant capability. Catechin and epicatechin content decreased with increasing heating temperature while gallocatechin and gallic acid content increased. Both catechin and epicatechin content had strong positive correlations (r > 0.91) with TPC and TFC, as well with FRAP and TEAC, suggesting that the GSF antioxidant activity is related to the presence of these particular compounds. Overall, while a decrease in antioxidant content was observed during heating, this occurred at higher baking temperatures. Thus GSF may be suitable for use as an ingredient in baked goods to bolster antioxidant content. In order for Merlot grape seed flour (GSF) to be used in baking as a source of additional antioxidant compounds, the impact of heating on the polyphenolic compounds in the GSF needed to be examined. Thermal treatment of Merlot GSF caused significant decreases in

  13. Content memory and temporal order memory for performed activities after severe closed-head injury.

    PubMed

    Schmitter-Edgecombe, Maureen; Wright, Matthew J

    2003-10-01

    Thirty severe closed-head injured (CHI) participants (more than 1 year postinjury) and 30 matched controls completed eight different cognitive activities. Participants' free recall and recognition of the activities provided a measure of content memory. Temporal order memory was assessed with a reconstruction task. CHI participants recalled and recognized fewer activities than did controls. However, the CHI and control groups did not differ in temporal order memory. For both groups, recognition memory was not correlated with temporal order memory. These results demonstrate intact temporal order memory for performed activities in a severe CHI population, and support the notion of separate processing of content memory and order information. Issues related to automaticity and the roles of the frontal lobes in temporal order memory are also discussed.

  14. Effects of Ge Gen Decoction on PGE2 content and COX activity in the degenarated cervical intervertebral discs of rats.

    PubMed

    Jun, Zhou; Fang, Suping; Huo, Hairu; Qi, Yun; Guo, Shuying; Jiang, Tingliang; Shi, Qi

    2005-09-01

    After the rat model of cervical spondylosis was developed for 6 months, the PGE2 content and COX activity in the cervical intervertebral discs were determined respectively by radioimmunoassay and catalytic activity assay. The results indicated that the PGE2 content and COX activity in the model rat increased significantly, and that Ge Gen Decoction could down-regulate the PGE2 content and inhibit COX activity. This is possibly one of the mechanisms of Ge Gen Decoction for treating cervical spondylosis.

  15. Glucosinolate content and nematicidal activity of Brazilian wild mustard tissues against Meloidogyne incognita in tomato

    USDA-ARS?s Scientific Manuscript database

    The wild mustard (Brassica juncea L.), an invasive weed of winter crops in Brazil, was evaluated for glucosinolate content of its plant tissues and nematicidal activity of its dry leaf meal (LM), whole seed meal (WSM) and hexane defatted seed meal (DSM) against Meloidogyne incognita on tomato plants...

  16. OpenSim-Supported Virtual Learning Environment: Transformative Content Representation, Facilitation, and Learning Activities

    ERIC Educational Resources Information Center

    Kim, Heesung; Ke, Fengfeng

    2016-01-01

    The pedagogical and design considerations for the use of a virtual reality (VR) learning environment are important for prospective and current teachers. However, empirical research investigating how preservice teachers interact with transformative content representation, facilitation, and learning activities in a VR educational simulation is still…

  17. Variability in tannin content, chemistry and activity in a diverse group of tannin containing sorghum cultivars

    USDA-ARS?s Scientific Manuscript database

    Tannins are large polyphenolic polymers and are known to bind proteins, limiting their digestibility. Tannins are also known for having excellent antioxidant potential. To examine the precise impact of tannin content and composition on the biological activities (protein binding, protein digestibil...

  18. Polyphenol content and antioxidant activity of California almonds depend on cultivar and harvest year

    USDA-ARS?s Scientific Manuscript database

    The polyphenol content and antioxidant activity of Nonpareil, Carmel, Butte, Sonora, Fritz, Mission, and Monterey almond cultivars harvested over 3 seasons in California were examined. LC-MS was employed to quantify 16 flavonoids and 2 phenolic acids in acidified methanol extracts of almond skins. T...

  19. Unlocking Doors to Self-Esteem. Content-Oriented Activities for Grades 7-12.

    ERIC Educational Resources Information Center

    Fox, C. Lynn; Weaver, Francine Lavin

    This book presents content-oriented activities for grades 7-12 designed to promote self-esteem. The first chapter presents the objectives and philosophy of this book. The second chapter presents the theoretical concepts as well as empirical data relative to the social development of adolescents. The third chapter deals with ways in which teachers…

  20. Total phenolic content and antioxidant activity of myrtle (Myrtus communis) extracts.

    PubMed

    Amensour, Mahassine; Sendra, Esther; Abrini, Jamal; Bouhdid, Samira; Pérez-Alvarez, José Angel; Fernández-López, Juana

    2009-06-01

    The total phenolic content and antioxidant activity of methanolic, ethanolic and aqueous extracts of myrtle (Myrtus communis) leaves and berries were measured to find new potential sources of natural antioxidants. Total phenolic content was assessed by the Folin-Ciocalteau assay, while the antioxidant activity was evaluated by three methods: diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, the reducing antioxidant power assay and beta-carotene linoleic acid assay. The total phenol content of myrtle extracts ranged between 9.0 and 35.6 mg GAE per g extract. For each solvent, leaf extracts contained significantly higher amount of total phenolic compounds than berry extracts. All of the extracts presented antioxidant capacity assessed by the three methods, but at different levels depending on the concentration, the extraction solvent and the part of the plant used. Generally, leaf extracts showed higher antioxidant activities than berry extracts, while the overall antioxidant strength was in the order methanol > water > ethanol in leaf extracts and methanol > ethanol > water in berry extracts. The phenolic content exhibited a positive correlation with the antioxidant activity: DPPH assay showed the highest correlation (r = 0.949), followed by the reducing power assay (r = 0.914) and the lowest for the beta-carotene linoleic acid assay (r = 0.722).

  1. The polyphenol content and antioxidant activities of the main edible vegetables in northern Vietnam.

    PubMed

    Thu, Nghiem Nguyet; Sakurai, Chika; Uto, Harumi; Van Chuyen, Nguyen; Lien, Do Thi Kim; Yamamoto, Shigeru; Ohmori, Reiko; Kondo, Kazuo

    2004-06-01

    Oxidized low-density lipoprotein (LDL) is considered a risk factor in atherosclerosis, and polyphenols are the potential agents to inhibit the oxidation of LDL. We determined the polyphenol contents and the antioxidant activities of commonly consumed vegetables in Vietnam and assessed the quantity of the polyphenol intake from vegetables in the current Vietnamese diet. The polyphenol contents in 30 kinds of vegetables was determined by the Folin-Ciocalteu method. The antioxidant activities of vegetables were evaluated by measuring the oxidation of LDL and the reduction of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. In this study, some herbs and edible wild vegetables possessed high contents of polyphenols and antioxidant activities. Among green vegetables, sweet potato leaves showed both a high polyphenol content and antioxidant activity. The mean polyphenol daily intake of the Vietnamese was a 595 mg catechin equivalent. Water spinach, a kind of green vegetable, contributed the highest amount (45%) of the total polyphenol intake, followed by other green vegetables. Neither herbs nor edible wild vegetables contributed significantly to the total polyphenol intake due to their low consumption. Green vegetables are therefore considered very important sources of polyphenol intake for the Vietnamese.

  2. Reading Activities in Content Areas: An Ideabook for Middle and Secondary Schools.

    ERIC Educational Resources Information Center

    Piercey, Dorothy

    This book suggests reading activities and teaching strategies to encourage students' success in the following middle school and secondary school content areas: business; driver education; English, speech, and journalism; art, music, and theater; foreign languages (French, Spanish, and German); health; home economics end industrial and vocational…

  3. Relationship Between Kernel Moisture Content and Water Activity in Different Maturity Stages of Peanut

    USDA-ARS?s Scientific Manuscript database

    The water activity (aw) and moisture content (KMC) of individual peanut kernels representing five different maturity stages were measured during a period of late-season drought stress leading up to normal harvest time. Curves were generated describing the relationship between aw and KMC for yellow 1...

  4. Aluminum toxicity in tomato. Part 2.Leaf gas exchange, chlorophyll content, and invertase activity

    Treesearch

    L. Simon; M. Kieger; Shi-Jean S. Sung; T.J. Smalley

    1994-01-01

    The effect of aluminum (Al) toxicity on leaf gas exchange, leaf chlorophyll content, and sucrose metabolizing enzyme activity of two tomato cultivars (Lycopersicon esculentum Mill. 'Mountain Pride' and 'Floramerica') was studied to determine the mechanism of growth reduction observed in a related study (Simon et al., 1994, Part 1).Plants were grown...

  5. OpenSim-Supported Virtual Learning Environment: Transformative Content Representation, Facilitation, and Learning Activities

    ERIC Educational Resources Information Center

    Kim, Heesung; Ke, Fengfeng

    2016-01-01

    The pedagogical and design considerations for the use of a virtual reality (VR) learning environment are important for prospective and current teachers. However, empirical research investigating how preservice teachers interact with transformative content representation, facilitation, and learning activities in a VR educational simulation is still…

  6. Plum Fruit Development Occurs via Gibberellin-Sensitive and -Insensitive DELLA Repressors.

    PubMed

    El-Sharkawy, Islam; Sherif, Sherif; Abdulla, Mahboob; Jayasankar, Subramanian

    2017-01-01

    Fruit growth depends on highly coordinated hormonal activities. The phytohormone gibberellin (GA) promotes growth by triggering degradation of the growth-repressing DELLA proteins; however, the extent to which such proteins contribute to GA-mediated fruit development remains to be clarified. Three new plum genes encoding DELLA proteins, PslGAI, PslRGL and PslRGA were isolated and functionally characterized. Analysis of expression profile during fruit development suggested that PslDELLA are transcriptionally regulated during flower and fruit ontogeny with potential positive regulation by GA and ethylene, depending on organ and developmental stage. PslGAI and PslRGL deduced proteins contain all domains present in typical DELLA proteins. However, PslRGA exhibited a degenerated DELLA domain and subsequently lacks in GID1-DELLA interaction property. PslDELLA-overexpression in WT Arabidopsis caused dramatic disruption in overall growth including root length, stem elongation, plant architecture, flower structure, fertility, and considerable retardation in development due to dramatic distortion in GA-metabolic pathway. GA treatment enhanced PslGAI/PslRGL interaction with PslGID1 receptors, causing protein destabilization and relief of growth-restraining effect. By contrast, PslRGA protein was not degraded by GA due to its inability to interact with PslGID1. Relative to other PslDELLA-mutants, PslRGA-plants displayed stronger constitutive repressive growth that was irreversible by GA application. The present results describe additional complexities in GA-signalling during plum fruit development, which may be particularly important to optimize successful reproductive growth.

  7. Exogenous gibberellins induce wheat spike development under short days only in the presence of VERNALIZATION1.

    PubMed

    Pearce, Stephen; Vanzetti, Leonardo S; Dubcovsky, Jorge

    2013-11-01

    The activation of the meristem identity gene VERNALIZATION1 (VRN1) is a critical regulatory point in wheat (Triticum spp.) flowering. In photoperiod-sensitive wheat varieties, VRN1 is expressed only under long days (LDs), but mutants carrying deletions in a regulatory element in its promoter show VRN1 transcription and early spike development under short days (SDs). However, complete spike development is delayed until plants are transferred to LDs, indicating the existence of an additional regulatory mechanism dependent on LDs. We show here that exogenous gibberellin (GA) application accelerates spike development under SDs, but only in wheat lines expressing VRN1. The simultaneous presence of GA and VRN1 results in the up-regulation of the floral meristem identity genes SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1-1 and LEAFY, whereas inhibition of GA biosynthesis with paclobutrazol precludes the LD induction of these two genes. The inductive role of GA on wheat flowering is further supported by the up-regulation of GA biosynthetic genes in the apices of plants transferred from SDs to LDs and in photoperiod-insensitive and transgenic wheat plants with increased FLOWERING LOCUS T transcription under SDs. The up-regulation of GA biosynthetic genes was not observed in the leaves of the same genetic stocks. Based on these observations, we propose a model in which FLOWERING LOCUS T is up-regulated in the leaves under LDs and is then transported to the shoot apical meristem, where it simultaneously induces the expression of VRN1 and GA biosynthetic genes, which are both required for the up-regulation of the early floral meristem genes SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1-1 and LEAFY and the timely development of the wheat spike.

  8. ARABIDOPSIS THALIANA HOMEOBOX25 Uncovers a Role for Gibberellins in Seed Longevity1[C][W

    PubMed Central

    Bueso, Eduardo; Muñoz-Bertomeu, Jesús; Campos, Francisco; Brunaud, Veronique; Martínez, Liliam; Sayas, Enric; Ballester, Patricia; Yenush, Lynne; Serrano, Ramón

    2014-01-01

    Seed longevity is crucial for agriculture and plant genetic diversity, but it is limited by cellular damage during storage. Seeds are protected against aging by cellular defenses and by structures such as the seed coat. We have screened an activation-tagging mutant collection of Arabidopsis (Arabidopsis thaliana) and selected four dominant mutants with improved seed longevity (isl1-1D to isl4-1D) under both natural and accelerated aging conditions. In the isl1-1D mutant, characterized in this work, overexpression of the transcription factor ARABIDOPSIS THALIANA HOMEOBOX25 (ATHB25; At5g65410) increases the expression of GIBBERELLIC ACID3-OXIDASE2, encoding a gibberellin (GA) biosynthetic enzyme, and the levels of GA1 and GA4 are higher (3.2- and 1.4-fold, respectively) in the mutant than in the wild type. The morphological and seed longevity phenotypes of the athb25-1D mutant were recapitulated in transgenic plants with moderate (4- to 6-fold) overexpression of ATHB25. Simultaneous knockdown of ATHB25, ATHB22, and ATHB31 expression decreases seed longevity, as does loss of ATHB25 and ATHB22 function in a double mutant line. Seeds from wild-type plants treated with GA and from a quintuple DELLA mutant (with constitutive GA signaling) are more tolerant to aging, providing additional evidence for a role of GA in seed longevity. A correlation was observed in several genotypes between seed longevity and mucilage formation at the seed surface, suggesting that GA may act by reinforcing the seed coat. This mechanism was supported by the observation of a maternal effect in reciprocal crosses between the wild type and the athb25-1D mutant. PMID:24335333

  9. Photocontrol of gibberellin metabolism in situ in maize. [Zea mays L

    SciTech Connect

    Rood, S.B.; Beall, F.D.; Pharis, R.P.

    1986-02-01

    Mature maize seeds were labeled with 10 to 100 pg per seed of (/sup 3/H) gibberellins (GA) and (/sup 3/H)GA glucosyl conjugate-like substances by feeding (/sup 3/H)GA/sub 20/ of high specific activity (2.3 Curies per millimole) during seed maturation. The dry seeds, which contained 14% (/sup 3/H)GA/sub 20/, 7% putative (/sup 3/H)GA/sub 1/ and 78% (/sup 3/H)GA glucosyl conjugate-like metabolites, were imbibed and germinated in the dark and under incandescent light. In both light and dark the proportion of (/sup 3/H)GA conjugate-like metabolities declined (relative to that in the mature dry seeds) during imbibition and up to germination at hour 36. This decline was accompanied by increases in the proportions of (/sup 3/H)GA/sub 20/ and putative (/sup 3/H)GA/sub 1/ thereby indicating hydrolysis, which was greater in the dark than in the light. The proportions of (/sup 3/H)GA conjugate-like substances in light-grown germinants were higher (121 and 141% of dark-grown) at 24 and 48 hour harvests and this statistically significant pattern was sustained up to 120 hours after imbibition. Conversely, the proportions of (/sup 3/H)GA/sub 20/ and putative (/sup 3/H)GA/sub 1/ were lower in the light-grown seedlings. Thus, during imbibition, hydrolysis (de-conjugation) of (/sup 3/H)GA glucosyl conjugate-like substances apparently occurred, and occurred more rapidly in the dark than in the light. Subsequently, during germination the reformation of (/sup 3/H)GA conjugate-like substances was less rapid in the dark than in the light.

  10. Gibberellin mediates daylength-controlled differentiation of vegetative meristems in strawberry (Fragaria × ananassa Duch)

    PubMed Central

    Hytönen, Timo; Elomaa, Paula; Moritz, Thomas; Junttila, Olavi

    2009-01-01

    Background Differentiation of long and short shoots is an important developmental trait in several species of the Rosaceae family. However, the physiological mechanisms controlling this differentiation are largely unknown. We have studied the role of gibberellin (GA) in regulation of shoot differentiation in strawberry (Fragaria × ananassa Duch.) cv. Korona. In strawberry, differentiation of axillary buds to runners (long shoot) or to crown branches (short shoot) is promoted by long-day and short-day conditions, respectively. Formation of crown branches is a prerequisite for satisfactory flowering because inflorescences are formed from the apical meristems of the crown. Results We found that both prohexadione-calcium and short photoperiod inhibited runner initiation and consequently led to induction of crown branching. In both cases, this correlated with a similar decline in GA1 level. Exogenous GA3 completely reversed the effect of prohexadione-calcium in a long photoperiod, but was only marginally effective in short-day grown plants. However, transfer of GA3-treated plants from short days to long days restored the normal runner formation. This did not occur in plants that were not treated with GA3. We also studied GA signalling homeostasis and found that the expression levels of several GA biosynthetic, signalling and target genes were similarly affected by prohexadione-calcium and short photoperiod in runner tips and axillary buds, respectively. Conclusion GA is needed for runner initiation in strawberry, and the inhibition of GA biosynthesis leads to the formation of crown branches. Our findings of similar changes in GA levels and in GA signalling homeostasis after prohexadione-calcium and short-day treatments, and photoperiod-dependent responsiveness of the axillary buds to GA indicate that GA plays a role also in the photoperiod-regulated differentiation of axillary buds. We propose that tightly regulated GA activity may control induction of cell division in

  11. GAMYB-like Genes, Flowering, and Gibberellin Signaling in Arabidopsis1

    PubMed Central

    Gocal, Gregory F.W.; Sheldon, Candice C.; Gubler, Frank; Moritz, Thomas; Bagnall, David J.; MacMillan, Colleen P.; Li, Song F.; Parish, Roger W.; Dennis, Elizabeth S.; Weigel, Detlef; King, Rod W.

    2001-01-01

    We have identified three Arabidopsis genes with GAMYB-like activity, AtMYB33, AtMYB65, and AtMYB101, which can substitute for barley (Hordeum vulgare) GAMYB in transactivating the barley α-amylase promoter. We have investigated the relationships between gibberellins (GAs), these GAMYB-like genes, and petiole elongation and flowering of Arabidopsis. Within 1 to 2 d of transferring plants from short- to long-day photoperiods, growth rate and erectness of petioles increased, and there were morphological changes at the shoot apex associated with the transition to flowering. These responses were accompanied by accumulation of GAs in the petioles (GA1 by 11-fold and GA4 by 3-fold), and an increase in expression of AtMYB33 at the shoot apex. Inhibition of GA biosynthesis using paclobutrazol blocked the petiole elongation induced by long days. Causality was suggested by the finding that, with GA treatment, plants flowered in short days, AtMYB33 expression increased at the shoot apex, and the petioles elongated and grew erect. That AtMYB33 may mediate a GA signaling role in flowering was supported by its ability to bind to a specific 8-bp sequence in the promoter of the floral meristem-identity gene, LEAFY, this same sequence being important in the GA response of the LEAFY promoter. One or more of these AtMYB genes may also play a role in the root tip during germination and, later, in stem tissue. These findings extend our earlier studies of GA signaling in the Gramineae to include a dicot species, Arabidopsis, and indicate that GAMYB-like genes may mediate GA signaling in growth and flowering responses. PMID:11743113

  12. ARABIDOPSIS THALIANA HOMEOBOX25 uncovers a role for Gibberellins in seed longevity.

    PubMed

    Bueso, Eduardo; Muñoz-Bertomeu, Jesús; Campos, Francisco; Brunaud, Veronique; Martínez, Liliam; Sayas, Enric; Ballester, Patricia; Yenush, Lynne; Serrano, Ramón

    2014-02-01

    Seed longevity is crucial for agriculture and plant genetic diversity, but it is limited by cellular damage during storage. Seeds are protected against aging by cellular defenses and by structures such as the seed coat. We have screened an activation-tagging mutant collection of Arabidopsis (Arabidopsis thaliana) and selected four dominant mutants with improved seed longevity (isl1-1D to isl4-1D) under both natural and accelerated aging conditions. In the isl1-1D mutant, characterized in this work, overexpression of the transcription factor ARABIDOPSIS THALIANA HOMEOBOX25 (ATHB25; At5g65410) increases the expression of GIBBERELLIC ACID3-OXIDASE2, encoding a gibberellin (GA) biosynthetic enzyme, and the levels of GA1 and GA4 are higher (3.2- and 1.4-fold, respectively) in the mutant than in the wild type. The morphological and seed longevity phenotypes of the athb25-1D mutant were recapitulated in transgenic plants with moderate (4- to 6-fold) overexpression of ATHB25. Simultaneous knockdown of ATHB25, ATHB22, and ATHB31 expression decreases seed longevity, as does loss of ATHB25 and ATHB22 function in a double mutant line. Seeds from wild-type plants treated with GA and from a quintuple DELLA mutant (with constitutive GA signaling) are more tolerant to aging, providing additional evidence for a role of GA in seed longevity. A correlation was observed in several genotypes between seed longevity and mucilage formation at the seed surface, suggesting that GA may act by reinforcing the seed coat. This mechanism was supported by the observation of a maternal effect in reciprocal crosses between the wild type and the athb25-1D mutant.

  13. Antihepatoma activity of Artocarpus communis is higher in fractions with high artocarpin content.

    PubMed

    Tzeng, Cheng-Wei; Yen, Feng-Lin; Lin, Liang-Tzung; Lee, Chiang-Wen; Yen, Ming-Hong; Tzeng, Wen-Sheng; Lin, Chun-Ching

    2014-01-01

    Extracts from natural plants have been used in traditional medicine for many centuries worldwide. Artocarpus communis is one such plant that has been used to treat liver cirrhosis, hypertension, and diabetes. To our knowledge, this study is the first to investigate the antihepatoma activity of A. communis toward HepG2 and PLC/PRF/5 cells and the first to explore the relationship between antihepatoma activity and the active compound artocarpin content in different fractions of A. communis. A. communis methanol extract and fractions induced dose-dependent reduction of tumor cell viability. DNA laddering analysis revealed that A. communis extract and fractions did not induce apoptosis in HepG2 and PLC/PRF/5 cells. Instead, acridine orange staining revealed that A. communis triggered autophagic cell death in a dose-dependent manner. The antihepatoma activity of A. communis is attributable to artocarpin. The fractions with the highest artocarpin content were also the fractions with the highest antihepatoma activity in the following order: dichloromethane fraction > methanol extract > ethyl acetate fraction > n-butanol fraction > n-hexane fraction. Taken together, A. communis showed antihepatoma activity through autophagic cell death. The effect was related to artocarpin content. Artocarpin could be considered an indicator of the anticancer potential of A. communis extract.

  14. Antihepatoma Activity of Artocarpus communis Is Higher in Fractions with High Artocarpin Content

    PubMed Central

    Tzeng, Cheng-Wei; Yen, Feng-Lin; Lee, Chiang-Wen; Yen, Ming-Hong; Tzeng, Wen-Sheng; Lin, Chun-Ching

    2014-01-01

    Extracts from natural plants have been used in traditional medicine for many centuries worldwide. Artocarpus communis is one such plant that has been used to treat liver cirrhosis, hypertension, and diabetes. To our knowledge, this study is the first to investigate the antihepatoma activity of A. communis toward HepG2 and PLC/PRF/5 cells and the first to explore the relationship between antihepatoma activity and the active compound artocarpin content in different fractions of A. communis. A. communis methanol extract and fractions induced dose-dependent reduction of tumor cell viability. DNA laddering analysis revealed that A. communis extract and fractions did not induce apoptosis in HepG2 and PLC/PRF/5 cells. Instead, acridine orange staining revealed that A. communis triggered autophagic cell death in a dose-dependent manner. The antihepatoma activity of A. communis is attributable to artocarpin. The fractions with the highest artocarpin content were also the fractions with the highest antihepatoma activity in the following order: dichloromethane fraction > methanol extract > ethyl acetate fraction > n-butanol fraction > n-hexane fraction. Taken together, A. communis showed antihepatoma activity through autophagic cell death. The effect was related to artocarpin content. Artocarpin could be considered an indicator of the anticancer potential of A. communis extract. PMID:25133268

  15. Great horsetail (Equisetum telmateia Ehrh.): Active substances content and biological effects

    PubMed Central

    Radojevic, Ivana D.; Stankovic, Milan S.; Stefanovic, Olgica D.; Topuzovic, Marina D.; Comic, Ljiljana R.; Ostojic, Aleksandar M.

    2012-01-01

    This paper deals with the antioxidant and antimicrobial activity, total phenolic content and concentrations of flavonoids of Equisetum telmateia extracts. Total phenolic content was determined with Folin-Ciocalteu reagent and it ranged between 129.0 to 262.7 mg GA/g. The concentration of flavonoids in various extracts of E. telmateia was determined using spectrophotometric method with aluminum chloride and obtained results varied from 112.6 to 199.8 mg RU/g. Antioxidant activity was monitored spectrophotometrically and expressed in terms of IC50 (µg/ml), and its values ranged from 33.4 to 982.2 µg/ml. The highest phenolic content, concentrations of flavonoids and capacity to neutralize DPPH radicals were found in the acetone extract. In vitro antimicrobial activity was determined using microdilution method. Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) were also determined. Testing was performed on 22 microorganisms, including 15 strains of bacteria (standard and clinical strains) and 7 species of fungi. There were statistically significant differences in activity between the extracts of E. telmateia. Different effects were noticed against the bacteria and the methanol extract appeared to be most efficient. All the extracts showed significant antibacterial activity against G+ bacteria and weak to moderate activity against other microorganisms. PMID:27350768

  16. Great horsetail (Equisetum telmateia Ehrh.): Active substances content and biological effects.

    PubMed

    Radojevic, Ivana D; Stankovic, Milan S; Stefanovic, Olgica D; Topuzovic, Marina D; Comic, Ljiljana R; Ostojic, Aleksandar M

    2012-01-01

    This paper deals with the antioxidant and antimicrobial activity, total phenolic content and concentrations of flavonoids of Equisetum telmateia extracts. Total phenolic content was determined with Folin-Ciocalteu reagent and it ranged between 129.0 to 262.7 mg GA/g. The concentration of flavonoids in various extracts of E. telmateia was determined using spectrophotometric method with aluminum chloride and obtained results varied from 112.6 to 199.8 mg RU/g. Antioxidant activity was monitored spectrophotometrically and expressed in terms of IC50 (µg/ml), and its values ranged from 33.4 to 982.2 µg/ml. The highest phenolic content, concentrations of flavonoids and capacity to neutralize DPPH radicals were found in the acetone extract. In vitro antimicrobial activity was determined using microdilution method. Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) were also determined. Testing was performed on 22 microorganisms, including 15 strains of bacteria (standard and clinical strains) and 7 species of fungi. There were statistically significant differences in activity between the extracts of E. telmateia. Different effects were noticed against the bacteria and the methanol extract appeared to be most efficient. All the extracts showed significant antibacterial activity against G+ bacteria and weak to moderate activity against other microorganisms.

  17. Metrologically Traceable Determination of the Water Content in Biopolymers: INRiM Activity

    NASA Astrophysics Data System (ADS)

    Rolle, F.; Beltramino, G.; Fernicola, V.; Sega, M.; Verdoja, A.

    2017-03-01

    Water content in materials is a key factor affecting many chemical and physical properties. In polymers of biological origin, it influences their stability and mechanical properties as well as their biodegradability. The present work describes the activity carried out at INRiM on the determination of water content in samples of a commercial starch-derived biopolymer widely used in shopping bags (Mater-Bi^{circledR }). Its water content, together with temperature, is the most influencing parameter affecting its biodegradability, because of the considerable impact on the microbial activity which is responsible for the biopolymer degradation in the environment. The main scope of the work was the establishment of a metrologically traceable procedure for the determination of water content by using two electrochemical methods, namely coulometric Karl Fischer (cKF) titration and evolved water vapour (EWV) analysis. The obtained results are presented. The most significant operational parameters were considered, and a particular attention was devoted to the establishment of metrological traceability of the measurement results by using appropriate calibration procedures, calibrated standards and suitable certified reference materials. Sample homogeneity and oven-drying temperature were found to be the most important influence quantities in the whole water content measurement process. The results of the two methods were in agreement within the stated uncertainties. Further development is foreseen for the application of cKF and EWV to other polymers.

  18. A correlation between tocopherol content and antioxidant activity in seeds and germinating seeds of soybean cultivars.

    PubMed

    Lee, Yu Young; Park, Hyang Mi; Hwang, Tae Young; Kim, Sun Lim; Kim, Mi Jung; Lee, Seuk Ki; Seo, Min Jung; Kim, Kee Jong; Kwon, Young-Up; Lee, Sang Chul; Kim, Yul Ho

    2015-03-15

    Tocopherols are crucial lipid-soluble antioxidants and essential nutrients. There is increasing interest in the biofortification of crops with vitamin E for reducing micronutrient malnutrition. However, relatively little is known about the development of soybean cultivars with high levels of tocopherol through combined breeding. Tocopherol contents of seeds and germinating seeds of 28 Korean soybean cultivars were analyzed and evaluated for health-promoting activities. Total tocopherol concentrations ranged from 203.9 to 503.1 µg g⁻¹ in seeds and from 20.1 to 230.1 µg g⁻¹ in germinating seeds. The traditional landraces of HaNagari (HN, 503.1 µg g⁻¹), Orialtae (OL, 486.6 µg g⁻¹), SuMoktae (SM, 476.5 µg g⁻¹) and SoRitae (SR, 475.5 µg g⁻¹) showed high levels of tocopherol content. The contents of the four isomers of tocopherol in seeds and germinating seeds were correlated with lipid peroxidation. The γ- and δ-tocopherol contents in seeds were related to 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity (0.434; P < 0.01 and 0.373; P < 0.05). Total tocopherol content was higher in soybean landraces as compared with modern cultivars developed by cross-breeding. These results suggest that soybean breeding is necessary to increase tocopherol levels. © 2014 Society of Chemical Industry.

  19. The jasmonate-responsive GTR1 transporter is required for gibberellin-mediated stamen development in Arabidopsis

    PubMed Central

    Saito, Hikaru; Oikawa, Takaya; Hamamoto, Shin; Ishimaru, Yasuhiro; Kanamori-Sato, Miyu; Sasaki-Sekimoto, Yuko; Utsumi, Tomoya; Chen, Jing; Kanno, Yuri; Masuda, Shinji; Kamiya, Yuji; Seo, Mitsunori; Uozumi, Nobuyuki; Ueda, Minoru; Ohta, Hiroyuki

    2015-01-01

    Plant hormones are transported across cell membranes during various physiological events. Recent identification of abscisic acid and strigolactone transporters suggests that transport of various plant hormones across membranes does not occur by simple diffusion but requires transporter proteins that are strictly regulated during development. Here, we report that a major glucosinolate transporter, GTR1/NPF2.10, is multifunctional and may be involved in hormone transport in Arabidopsis thaliana. When heterologously expressed in oocytes, GTR1 transports jasmonoyl-isoleucine and gibberellin in addition to glucosinolates. gtr1 mutants are severely impaired in filament elongation and anther dehiscence resulting in reduced fertility, but these phenotypes can be rescued by gibberellin treatment. These results suggest that GTR1 may be a multifunctional transporter for the structurally distinct compounds glucosinolates, jasmonoyl-isoleucine and gibberellin, and may positively regulate stamen development by mediating gibberellin supply. PMID:25648767

  20. Estimating water content in an active landfill with the aid of GPR.

    PubMed

    Yochim, April; Zytner, Richard G; McBean, Edward A; Endres, Anthony L

    2013-10-01

    Landfill gas (LFG) receives a great deal of attention due to both negative and positive environmental impacts, global warming and a green energy source, respectively. However, predicting the quantity of LFG generated at a given landfill, whether active or closed is difficult due to the heterogeneities present in waste, and the lack of accurate in situ waste parameters like water content. Accordingly, ground penetrating radar (GPR) was evaluated as a tool for estimating in situ water content. Due to the large degree of subsurface heterogeneity and the electrically conductive clay cap covering landfills, both of which affect the transmission of the electromagnetic pulses, there is much scepticism concerning the use of GPR to quantify in situ water content within a municipal landfill. Two landfills were studied. The first landfill was used to develop the measurement protocols, while the second landfill provided a means of confirming these protocols. GPR measurements were initially completed using the surface GPR approach, but the lack of success led to the use of borehole (BH) GPR. Both zero offset profiling (ZOP) and multiple offset gathers (MOG) modes were tried, with the results indicating that BH GPR using the ZOP mode is the most simple and efficient method to measure in situ water content. The best results were obtained at a separation distance of 2m, where higher the water content, smaller the effective separation distance. However, an increase in water content did appear to increase the accuracy of the GPR measurements. For the effective separation distance of 2m at both landfills, the difference between GPR and lab measured water contents were reasonable at 33.9% for the drier landfill and 18.1% for the wetter landfill. Infiltration experiments also showed the potential to measure small increases in water content.

  1. Content analysis of prime-time television coverage of physical activity, 1970-2001.

    PubMed

    Silver Wallace, Lorraine; Leenders, Nicole

    2004-02-01

    The purpose of this study was to examine how major nightly television networks reported on the health benefits of physical activity. A retrospective content analysis of physical activity coverage on four major nightly television networks from 1970 to 2001 was performed. The Vanderbilt Television News Archives were searched for keywords "physical activity," "physical fitness," and "exercise." During the 31-year time period, 111 non-overlapping reports aired on all networks combined. The link between physical activity and health was reported in 53 (47.7%) articles, with general health (n =16, 14.4%) and heart disease (n =12, 12.6%) cited most frequently. Just three broadcasts related to the Surgeon's General Report on Physical Activity and Health were aired following its publication in 1996. Although the protective health benefits of physical activity are well established, physical activity received a modest amount of television coverage from 1970 through 2001.

  2. Physiological Content and Intrinsic Activities of 10 Cytochrome P450 Isoforms in Human Normal Liver Microsomes.

    PubMed

    Zhang, Hai-Feng; Wang, Huan-Huan; Gao, Na; Wei, Jun-Ying; Tian, Xin; Zhao, Yan; Fang, Yan; Zhou, Jun; Wen, Qiang; Gao, Jie; Zhang, Yang-Jun; Qian, Xiao-Hong; Qiao, Hai-Ling

    2016-07-01

    Due to a lack of physiologic cytochrome P450 (P450) isoform content, P450 activity is typically only determined at the microsomal level (per milligram of microsomal protein) and not at the isoform level (per picomole of P450 isoform), which could result in the misunderstanding of variations in P450 activity between individuals and further hinder development of personalized medicine. We found that there were large variations in protein content, mRNA levels, and intrinsic activities of the 10 P450s in 100 human liver samples, in which CYP2E1 and CYP2C9 showed the highest expression levels. P450 gene polymorphisms had different effects on activity at two levels: CYP3A5*3 and CYP2A6*9 alleles conferred increased activity at the isoform level but decreased activity at the microsomal level; CYP2C9*3 had no effect at the isoform level but decreased activity at the microsomal level. The different effects at each level stem from the different effects of each polymorphism on the resulting P450 protein. Individuals with CYP2A6*1/*4, CYP2A6*1/*9, CYP2C9*1/*3, CYP2D6 100C>T TT, CYP2E1 7632T>A AA, CYP3A5*1*3, and CYP3A5*3*3 genotypes had significantly lower protein content, whereas CYP2D6 1661G>C mutants had a higher protein content. In conclusion, we first offered the physiologic data of 10 P450 isoform contents and found that some single nucleotide polymorphisms had obvious effects on P450 expression in human normal livers. The effects of gene polymorphisms on intrinsic P450 activity at the isoform level were quite different from those at the microsomal level, which might be due to changes in P450 protein content. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  3. Get the news on physical activity research: a content analysis of physical activity research in the Canadian print media.

    PubMed

    Faulkner, Guy; Finlay, Sara-Jane; Roy, Stephannie C

    2007-04-01

    News media may play a critical role in disseminating research about physical activity and health. This study examined how much physical activity research gets reported in the media and its prominence and credibility. A content analysis was conducted of the reporting of physical activity research in Canadian national and local newspapers from November 2004 to April 2005. Physical activity research was given some prominence and treated as news through the use of several devices to infer credibility. However, newspapers appeared to invest little in the production of physical activity research as news and information about research methodology was infrequent. While stories reporting physical activity research were given some prominence and credibility, the lack of significant investment and the limited reporting on research methodology suggests that important aspects of research related to physical activity may not be well represented in newspaper coverage.

  4. Correlation between Sun Protection Factor and Antioxidant Activity, Phenol and Flavonoid Contents of some Medicinal Plants

    PubMed Central

    Ebrahimzadeh, Mohammad Ali; Enayatifard, Reza; Khalili, Masoumeh; Ghaffarloo, Mahdieh; Saeedi, Majid; Yazdani Charati, Jamshid

    2014-01-01

    Long exposure of UV radiation increases risk of skin diseases such as cancer and photoallergic reactions. UV-B (280-320 nm) radiation is mainly responsible for inducing the skin problems. Skin protection is a suitable method against ultraviolet radiation-induced damage. Various synthetic agents have been used as photo protective but because of their potential toxicity in humans, they have limited usage. Natural substances have been recently considered as potential sunscreen resources due to their absorption in the UV region and their antioxidant activity. In the present study, the UV protective effects of 20 extracts from four common medicinal plants were evaluated. Their phenol and flavonoid contents and antioxidant activities were determined and correlation between SPF and these contents were evaluated. SPFs were between 0.102 and 24.470. The highest value was reached with ultrasonic extract of Crataegus pentagyna (SPF = 24.47) followed by methanolic extract of Feijoa sellowiana (SPF = 1.30). Good correlation was found between SPF and phenolic contents (Correlation Coefficient = 0.55 and p = 0.01) but no correlations were found between SPF and flavonoid contents or antioxidant activity. These extracts can be used alone or as additives in other sun screen formulations to enhance their SPF. PMID:25276206

  5. Correlation between Sun Protection Factor and Antioxidant Activity, Phenol and Flavonoid Contents of some Medicinal Plants.

    PubMed

    Ebrahimzadeh, Mohammad Ali; Enayatifard, Reza; Khalili, Masoumeh; Ghaffarloo, Mahdieh; Saeedi, Majid; Yazdani Charati, Jamshid

    2014-01-01

    Long exposure of UV radiation increases risk of skin diseases such as cancer and photoallergic reactions. UV-B (280-320 nm) radiation is mainly responsible for inducing the skin problems. Skin protection is a suitable method against ultraviolet radiation-induced damage. Various synthetic agents have been used as photo protective but because of their potential toxicity in humans, they have limited usage. Natural substances have been recently considered as potential sunscreen resources due to their absorption in the UV region and their antioxidant activity. In the present study, the UV protective effects of 20 extracts from four common medicinal plants were evaluated. Their phenol and flavonoid contents and antioxidant activities were determined and correlation between SPF and these contents were evaluated. SPFs were between 0.102 and 24.470. The highest value was reached with ultrasonic extract of Crataegus pentagyna (SPF = 24.47) followed by methanolic extract of Feijoa sellowiana (SPF = 1.30). Good correlation was found between SPF and phenolic contents (Correlation Coefficient = 0.55 and p = 0.01) but no correlations were found between SPF and flavonoid contents or antioxidant activity. These extracts can be used alone or as additives in other sun screen formulations to enhance their SPF.

  6. Antioxidant activity and phenolic content of Bergenia crassifolia, B. x ornata and B. ciliata.

    PubMed

    Hendrychová, Helena; Vildová, Anna; Kocevar-Glavac, Nina; Tůmová, Lenka; Kanybekovna, Elnura Abdykerimova; Tůma, Jirí

    2014-04-01

    This study focused on a phytochemical analysis of Bergenia crassifolia (L.) Fritsch., B. ciliata (Haw.) Sternb., and B. x ornata Stein. and evaluation of their free radical scavenging properties. Arbutin and total tannin contents of the leaves of the Bergenia species were determined during different seasons. The present study also aimed at analyzing, for the first time, environmental influence on concentrations of phenolic metabolites in Bergenia leaves. The highest total tannin content was found in the leaves of B. crassifolia (24.9-48.7 mg x g(-1) DW) and B. x ornata (36.9 mg.g(-1) DW). The highest amount of arbutin was in the leaves of B. x ornata (35.8-51.0 mg.g(-1) DW) and B. crassifolia (24.6-41.7 mg x g(-1) DW). Autumn was better than spring for the collection of Bergenia leaves for the highest amount of arbutin (B. x ornata: 51.0 mg x g(-1) DW). Free radical scavenging potential, in DPPH and ABTS assays, of the water leaf extracts revealed that extracts of B. crassifolia and B. x ornata are the most active radical scavengers. Antioxidant activity correlated well with the content of total tannin, especially in the ABTS assay, which suggests an important role for these compounds in antioxidant activity. It was shown that phenolic concentrations in Bergenia leaves are affected by seasonal factors. A significant correlation was found between arbutin and tannin contents and the average humidity.

  7. The Content of Secondary Metabolites and Antioxidant Activity of Wild Strawberry Fruit (Fragaria vesca L.)

    PubMed Central

    Dyduch-Siemińska, Magdalena; Najda, Agnieszka; Dyduch, Jan; Gantner, Magdalena; Klimek, Kamila

    2015-01-01

    Chemical analyses carried out in 2011–2013 aimed at evaluating the contents of flavonoids, free phenolic acids, tannins, anthocyanins, and antioxidant activity (%) by means of DPPH radical neutralization ability in fresh and air-dried fruits of three wild strawberry cultivars. Examinations revealed differences in contents of biologically active substances determined in raw versus dried material depending on the cultivar. Mean concentrations of flavonoids and tannins were highest in raw fruits of “Baron von Solemacher” cv., which amounted to 1.244 mg·g−1 and 6.09%, respectively. Fresh fruits of “Regina” cv. were characterized by the highest average content of phenolic acids and anthocyanins: 4.987 mg·g−1 and 0.636 mg·100 g−1. The pattern of mean contents of biologically active substances analyzed in air-dried fruits was similar. Significant differences in abilities to neutralize the DPPH radical to diphenylpicrylhydrazine by extracts made of examined wild strawberry fruits were also indicated. PMID:26539306

  8. Effects of thyroid hormone on food intake, hypothalamic Na/K ATPase activity and ATP content.

    PubMed

    Luo, LuGuang; MacLean, David B

    2003-05-30

    The effects of thyroid hormone on whole body energy metabolism and compensatory effects on food intake are well established. However, the hypothalamic mechanisms that translate perceived whole body energy demands into subsequent appetitive behavior are incompletely understood. In order to address this question, we tested the effects of T3 on food intake and body weight in rats and measured neuronal Na/K ATPase activity and ATP content in the hypothalamus. Intraperitoneal T3 (100 microg/kg BW) administered for 6 consecutive days increased 24-h rat food intake from control, 26.6+/-1.2, to T3-treated 33.2+/-1.6 g (P<0.01). In T3-treated rats, rubidium-86 (86Rb) uptake (measured as a marker of Na/K ATPase activity) in ex vivo hypothalamic tissue increased (P<0.01) while the content of ATP in the ventral hypothalamus declined following T3 treatment (P<0.01). In another model of energy deficit, which was induced by a very low calorie diet, ATP content was also reduced in the hypothalamus compared to rats fed ad libitum. In summary, increased food intake in response to T3 may be secondary to decreased hypothalamic ATP content, perhaps resulting from both increased Na/K ATPase activity in the hypothalamus and metabolic signaling induced by whole body caloric deficit.

  9. Effects of γ-irradiation on phenolics content, antioxidant activity and physicochemical properties of whole grainrice

    NASA Astrophysics Data System (ADS)

    Shao, Yafang; Tang, Fufu; Xu, Feifei; Wang, Yuefei; Bao, Jinsong

    2013-04-01

    Three rice genotypes with different color were gamma irradiated at a dose of 2, 4, 6, 8and 10 kGy. The aim of this study was to investigate the effect of gamma irradiation on the phenolics content and the antioxidant activity, as well as physicochemical properties of whole grain rice. The bound phenolics content in all the genotypes were significantly increased with the increase of dose of irradiation. Gamma irradiation at high dose significantly increased the free, bound and total antioxidant activities of three rice genotypes except for the free antioxidant activities of red rice. Though the color parameters were slightly changed, these changes could not be visibly identified. Rapid visco-analyzer (RVA) viscosities and gel hardness decreased continuously with the increase of the irradiation doses. It is suggested that gamma irradiation enhanced the antioxidant potential and eating quality of whole grainrice.

  10. Phenolic content and antioxidant activity of Hibiscus cannabinus L. seed extracts after sequential solvent extraction.

    PubMed

    Yusri, Noordin Mohd; Chan, Kim Wei; Iqbal, Shahid; Ismail, Maznah

    2012-10-25

    A sequential solvent extraction scheme was employed for the extraction of antioxidant compounds from kenaf (Hibiscus cannabinus L.) seeds. Yield of extracts varied widely among the solvents and was the highest for hexane extract (16.6% based on dry weight basis), while water extract exhibited the highest total phenolic content (18.78 mg GAE/g extract), total flavonoid content (2.49 mg RE/g extract), and antioxidant activities (p < 0.05). DPPH and hydroxyl radical scavenging, β-carotene bleaching, metal chelating activity, ferric thiocyanate and thiobarbituric acid reactive substances assays were employed to comprehensively assess the antioxidant potential of different solvent extracts prepared sequentially. Besides water, methanolic extract also exhibited high retardation towards the formation of hydroperoxides and thiobarbituric acid reactive substances in the total antioxidant activity tests (p < 0.05). As conclusion, water and methanol extracts of kenaf seed may potentially serve as new sources of antioxidants for food and nutraceutical applications.

  11. Determination of antioxidant activity of wine byproducts and its correlation with polyphenolic content.

    PubMed

    Alonso, Angeles M; Guillén, Dominico A; Barroso, Carmelo G; Puertas, Belén; García, Alberto

    2002-10-09

    It has been demonstrated that wine and other products derived from the grape have a high antioxidant capability; as a possible consequence of this, they may have potential benefits for health. The byproducts of the winemaking process represent a source of antioxidant compounds that has been relatively unexploited to date, but that is now the subject of increasing industrial interest. This article describes an approach to the study of the antioxidant activity of grape marcs, stalks, and dregs of both white and red varieties. This activity is compared with the measurements of their content of total polyphenols and of individual polyphenolic compounds, identified and quantified by HPLC. From the results we have been able to establish a positive correlation between the antioxidant activity and the total polyphenolic content of samples, but not with specific compounds.

  12. Antioxidant activities and polyphenolic contents of three selected Micromeria species from Croatia.

    PubMed

    Vladimir-Knežević, Sanda; Blažeković, Biljana; Štefan, Maja Bival; Alegro, Antun; Koszegi, Tamás; Petrik, József

    2011-02-10

    Antioxidant activities of three selected Micromeria species growing in Croatia (M. croatica, M. juliana and M. thymifolia) were evaluated using five different antioxidant assays, in comparison with plant polyphenolic constituents and reference antioxidants. All studied ethanolic extracts exhibited considerable activity to scavenge DPPH and hydroxyl free radicals, reducing power, iron chelating ability and total antioxidant capacity in the order: M. croatica > M. juliana > M. thymifolia. Total polyphenol (9.69-13.66%), phenolic acid (5.26-6.84%), flavonoid (0.01-0.09%) and tannin (3.07-6.48%) contents in dried plant samples were determined spectrophotometrically. A strong positive correlation between antioxidant activities and contents of phenolic acids and tannins was found, indicating their responsibility for effectiveness of tested plants. Our findings established Micromeria species as a rich source of antioxidant polyphenols, especially the endemic M. croatica.

  13. Phenolic content and antioxidant activity of Pereskia grandifolia Haw. (Cactaceae) extracts

    PubMed Central

    Sim, K. S.; Nurestri, A. M. Sri; Norhanom, A. W.

    2010-01-01

    The leaves of Pereskia grandifolia Haw. (Cactaceae), commonly known as “Jarum Tujuh Bilah” in Malaysia, have been traditionally used as natural remedy in folk medicine by the locals. In the present study, the antioxidant potential of P. grandifolia crude methanol and its fractionated extracts (hexane, ethyl acetate and water) have been investigated, employing three different established testing systems, such as scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, reducing power assay and β-carotene method. The total phenolic content of the P. grandifolia extracts was also assessed by the Folin-Ciocalteau’s method. The ethyl acetate extract showed significantly the highest total phenolic content, DPPH scavenging ability and antioxidant activity in β-carotene bleaching assay while the hexane extract possessed significantly strongest reducing power. The data obtained in these testing systems clearly establish the antioxidant potency of P. grandifolia. As such, this is the first report on the antioxidant activities of P. grandifolia. PMID:20931088

  14. Exploring active layer thaw depth and water content dynamics with multi-channel GPR

    NASA Astrophysics Data System (ADS)

    Wollschlaeger, U.; Gerhards, H.; Westermann, S.; Pan, X.; Boike, J.; Schiwek, P.; Yu, Q.; Roth, K.

    2011-12-01

    In permafrost landscapes, the active layer is the highly dynamic uppermost section of the ground where many important hydrological, biological and geomorphological processes take place. Active layer hydrological processes are controlled by many different factors like thaw depth, soil textural properties, vegetation, and snow cover. These may lead to complex runoff patterns that are difficult to estimate from point measurements in boreholes. New multi-channel GPR systems provide the opportunity to non-invasively estimate reflector depth and average volumetric water content of distinct soil layers over distances ranging from some ten meters up to a few kilometers. Due to the abrupt change in dielectric permittivity between frozen and unfrozen ground, multi-channel GPR is a valuable technique for mapping the depth of the frost table along with the volumetric water content of the active layer without the need of laborious drillings or frost probe measurements. Knowing both values, the total amount of water stored in the active layer can be determined which may be used as an estimate of its latent heat content. Time series of measurements allow spatial monitoring of the progression of the thawing front. Multi-channel GPR thus offers new opportunities for monitoring active layer hydrological processes. This presentation will provide a brief introduction of the multi-channel GPR evaluation technique and will present different applications from several permafrost sites.

  15. Effect of roasting on phenolic content and antioxidant activities of whole cashew nuts, kernels, and testa.

    PubMed

    Chandrasekara, Neel; Shahidi, Fereidoon

    2011-05-11

    The effect of roasting on the content of phenolic compounds and antioxidant properties of cashew nuts and testa was studied. Whole cashew nuts, subjected to low-temperature (LT) and high-temperature (HT) treatments, were used to determine the antioxidant activity of products. Antioxidant activities of cashew nut, kernel, and testa phenolics extracted increased as the roasting temperature increased. The highest activity, as determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, oxygen radical absorbance capacity (ORAC), hydroxyl radical scavenging capacity, Trolox equivalent antioxidant activity (TEAC), and reducing power, was achieved when nuts were roasted at 130 °C for 33 min. Furthermore, roasting increased the total phenolic content (TPC) in both the soluble and bound extracts from whole nut, kernel, and testa but decreased that of the proanthocyanidins (PC) except for the soluble extract of cashew kernels. In addition, cashew testa afforded a higher extract yield, TPC, and PC in both soluble and bound fractions compared to that in whole nuts and kernels. Phenolic acids, namely, syringic (the predominant one), gallic, and p-coumaric acids, were identified. Flavonoids, namely, (+)-catechin, (-)-epicatechin, and epigallocatechin, were also identified, and their contents increased with increasing temperature. The results so obtained suggest that HT-short time (HTST) roasting effectively enhances the antioxidant activity of cashew nuts and testa.

  16. Active Learning Strategies for Phenotypic Profiling of High-Content Screens.

    PubMed

    Smith, Kevin; Horvath, Peter

    2014-06-01

    High-content screening is a powerful method to discover new drugs and carry out basic biological research. Increasingly, high-content screens have come to rely on supervised machine learning (SML) to perform automatic phenotypic classification as an essential step of the analysis. However, this comes at a cost, namely, the labeled examples required to train the predictive model. Classification performance increases with the number of labeled examples, and because labeling examples demands time from an expert, the training process represents a significant time investment. Active learning strategies attempt to overcome this bottleneck by presenting the most relevant examples to the annotator, thereby achieving high accuracy while minimizing the cost of obtaining labeled data. In this article, we investigate the impact of active learning on single-cell-based phenotype recognition, using data from three large-scale RNA interference high-content screens representing diverse phenotypic profiling problems. We consider several combinations of active learning strategies and popular SML methods. Our results show that active learning significantly reduces the time cost and can be used to reveal the same phenotypic targets identified using SML. We also identify combinations of active learning strategies and SML methods which perform better than others on the phenotypic profiling problems we studied. © 2014 Society for Laboratory Automation and Screening.

  17. Antioxidant activity and phenolic content of leaf infusions of Myrtaceae species from Cerrado (Brazilian Savanna).

    PubMed

    Takao, L K; Imatomi, M; Gualtieri, S C J

    2015-11-01

    There is considerable interest in identifying new antioxidants from plant materials. Several studies have emphasized the antioxidant activity of species belonging to the Myrtaceae family. However, there are few reports on these species from the Cerrado (Brazilian savanna). In this study, the antioxidant activity and phenolic content of 12 native Myrtaceae species from the Cerrado were evaluated (Blepharocalyx salicifolius, Eugenia bimarginata, Eugenia dysenterica, Eugenia klotzschiana, Hexachlamys edulis, Myrcia bella, Myrcia lingua, Myrcia splendens, Myrcia tomentosa, Psidium australe, Psidium cinereum, and Psidium laruotteanum). Antioxidant potential was assessed using the antioxidant activity index (AAI) by the DPPH method and total phenolic content (TPC) by the Folin-Ciocalteu assay. There was a high correlation between TPC and AAI values. Psidium laruotteanum showed the highest TPC (576.56 mg GAE/g extract) and was the most potent antioxidant (AAI = 7.97, IC50 = 3.86 µg·mL-1), with activity close to that of pure quercetin (IC50 = 2.99 µg·mL-1). The extracts of nine species showed IC50 of 6.24-8.75 µg·mL-1. Most species showed TPC and AAI values similar to or higher than those for Camellia sinensis, a commonly consumed tea with strong antioxidant properties. The results reveal that the analyzed Myrtaceae species from the Cerrado possess high phenolic contents and antioxidant activities. Thus, they are a potential source of new natural antioxidants.

  18. Arylsulphatase activity and sulphate content in relation to crop rotation and fertilization of soil

    NASA Astrophysics Data System (ADS)

    Siwik-Ziomek, Anetta; Lemanowicz, Joanna; Koper, Jan

    2016-07-01

    The aim of the study was to investigate the effect of varying rates of FYM (0, 20, 40, 60 Mg ha-1) and nitrogen N0, N1, N2, and N3 on the content of sulphate sulphur (VI) and the activity of arylsulphatase, which participates in the transformations of this element in Haplic Luvisol. The study report is based on a long-term field experiment with two different crop rotations: A - recognized as exhausting the humus from soil and B - recognized as enriching the soil with humus. During the cultivation of the plants, the soil was sampled four times from corn and a red clover cultivar and grass. The FYM fertilization rate for which the highest arylsulphatase activity and the content of sulphates were identified was 60 Mg ha-1. An inhibitory effect of high rates (90 and 135 kg N ha-1) of ammonium nitrate on the arylsulphatase activity was also observed. A significant correlation between the content of carbon, nitrogen, and sulphates and the arylsulphatase activity was recorded. The investigation on the effect of combined application of farmyard manure and mineral nitrogen fertilization on the activity of arylsulphatase participating in the sulphur cycling was launched to examine the problem in detail.

  19. Varietal differences in phenolic content and antioxidant and antiproliferative activities of onions.

    PubMed

    Yang, Jun; Meyers, Katherine J; van der Heide, Jan; Liu, Rui Hai

    2004-11-03

    Epidemiological studies have indicated that the consumption of fruits and vegetables is associated with a reduced risk for the development of chronic diseases, such as cardiovascular disease and cancer. Phytochemicals, including phenolics and flavonoids, are suggested to be the major bioactive compounds contributing to the health benefits of fruits and vegetables. Onions are a major source of dietary flavonoids; however, there may exist varietal differences in composition, concentration, and beneficial activities. To characterize these differences, shallots and 10 onion (Allium cepa L.) varieties commonly available in the United States (Western Yellow, Northern Red, New York Bold, Western White, Peruvian Sweet, Empire Sweet, Mexico, Texas 1015, Imperial Valley Sweet, and Vidalia) were evaluated for total phenolic and flavonoid contents and antioxidant and antiproliferative activities. Shallots contained the highest total phenolic content (114.7 +/- 10.0 mg/100 g of sample) among the varieties tested, with a 6-fold difference observed when compared to the variety with the lowest phenolic content (Vidalia, p < 0.05). Western Yellow onion variety exhibited the highest total flavonoid content (69.2 +/- 3.7 mg/100 g of onion) of the varieties tested, with an 11-fold difference when compared to the variety with the lowest flavonoid content (Western White, p < 0.05). Shallots exhibited the highest total antioxidant activity (45.5 +/- 2.1 micromol of vitamin C equiv/g of onion), followed by Western Yellow, New York Bold, Northern Red, Mexico, Empire Sweet, Western White, Peruvian Sweet, Texas 1015, Imperial Valley Sweet, and Vidalia. For all varieties, both total phenolic and flavonoid contents were strongly correlated with total antioxidant activity (R (2) = 0.9668, p < 0.05; and R (2) = 0.7033, p < 0.05, respectively). The proliferation of HepG(2) and Caco-2 cells was significantly inhibited in a dose-dependent fashion after exposure to the Western Yellow, shallots, New

  20. Thyrotropin increases hepatic triglyceride content through upregulation of SREBP-1c activity.

    PubMed

    Yan, Fang; Wang, Qi; Lu, Ming; Chen, Wenbin; Song, Yongfeng; Jing, Fei; Guan, Youfei; Wang, Laicheng; Lin, Yanliang; Bo, Tao; Zhang, Jie; Wang, Tingting; Xin, Wei; Yu, Chunxiao; Guan, Qingbo; Zhou, Xinli; Gao, Ling; Xu, Chao; Zhao, Jiajun

    2014-12-01

    Hallmarks of non-alcoholic fatty liver disease (NAFLD) are increased triglyceride accumulation within hepatocytes. The prevalence of NAFLD increases steadily with increasing thyrotropin (TSH) levels. However, the underlying mechanisms are largely unknown. Here, we focused on exploring the effect and mechanism of TSH on the hepatic triglyceride content. As the function of TSH is mediated through the TSH receptor (TSHR), Tshr(-/-) mice (supplemented with thyroxine) were used. Liver steatosis and triglyceride content were analysed in Tshr(-/-) and Tshr(+/+) mice fed a high-fat or normal chow diet, as well as in Srebp-1c(-/-) and Tshr(-/-)Srebp-1c(-/-) mice. The expression levels of proteins and genes involved in liver triglyceride metabolism was measured. Compared with control littermates, the high-fat diet induced a relatively low degree of liver steatosis in Tshr(-/-) mice. Even under chow diet, hepatic triglyceride content was decreased in Tshr(-/-) mice. TSH caused concentration- and time-dependent effects on intracellular triglyceride contents in hepatocytes in vitro. The activity of SREBP-1c, a key regulator involved in triglyceride metabolism and in the pathogenesis of NAFLD, was significantly lower in Tshr(-/-) mice. In Tshr(-/-)Srebp-1c(-/-) mice, the liver triglyceride content showed no significant difference compared with Tshr(+/+)Srebp-1c(-/-) mice. When mice were injected with forskolin (cAMP activator), H89 (inhibitor of PKA) or AICAR (AMPK activator), or HeG2 cells received MK886 (PPARα inhibitor), triglyceride contents presented in a manner dependent on SREBP-1c activity. The mechanism, underlying TSH-induced liver triglyceride accumulation, involved that TSH, through its receptor TSHR, triggered hepatic SREBP-1c activity via the cAMP/PKA/PPARα pathway associated with decreased AMPK, which further increased the expression of genes associated with lipogenesis. TSH increased the hepatic triglyceride content, indicating an essential role for TSH in the

  1. Phenolic content, antioxidant effect and cytotoxic activity of Leea indica leaves.

    PubMed

    Reddy, Nidyaletchmy Subba; Navanesan, Suerialoasan; Sinniah, Saravana Kumar; Wahab, Norhanom Abdul; Sim, Kae Shin

    2012-08-17

    The leaves of Leea indica (Vitaceae), commonly known as 'Huo Tong Shu' in Malaysia, have been traditionally used as natural remedy in folk medicine by the locals. The current study reports the outcome of antioxidant and cytotoxic investigation of L. indica leaves. To the best of our knowledge, this is the first report of L. indica leaf crude ethanol and its fractionated extracts (hexane, ethyl acetate and water) for evaluation of total phenolic content, antioxidant effect and cytotoxic activity against colon cancer cell lines. In the present study, L. indica leaf crude ethanol and its fractionated extracts (hexane, ethyl acetate and water) were firstly prepared prior to phenolic content, antioxidant effect and cytotoxic activity assessment. Folin-Ciocalteau's method was used for the measurement of total phenolic content of the extracts. The antioxidant activity was measured by employing three different established testing systems, such as scavenging activity on DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals, reducing power assay and SOD (superoxide dismutase) activity assay. The cytotoxic activity of the extracts were evaluated against three colon cancer cell lines with varying molecular characteristics (HT-29, HCT-15 and HCT-116) by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The total phenolic content and antioxidant capabilities differed significantly among the L. indica leaf extracts. A strong correlation between total phenolic content and antioxidant properties was found, indicating that phenolic compounds are the major contributor to the antioxidant properties of these extracts. Among the crude ethanol and its fractionated extracts, fractionated water extract showed significantly the highest total phenolic content and strongest antioxidant effect in all the antioxidant testing systems employed in this study. All the four extracts exert no damage to the selected colon cancer cells. The data obtained in these testing systems clearly

  2. Phenolic content, antioxidant effect and cytotoxic activity of Leea indica leaves

    PubMed Central

    2012-01-01

    Background The leaves of Leea indica (Vitaceae), commonly known as ‘Huo Tong Shu’ in Malaysia, have been traditionally used as natural remedy in folk medicine by the locals. The current study reports the outcome of antioxidant and cytotoxic investigation of L. indica leaves. To the best of our knowledge, this is the first report of L. indica leaf crude ethanol and its fractionated extracts (hexane, ethyl acetate and water) for evaluation of total phenolic content, antioxidant effect and cytotoxic activity against colon cancer cell lines. Methods In the present study, L. indica leaf crude ethanol and its fractionated extracts (hexane, ethyl acetate and water) were firstly prepared prior to phenolic content, antioxidant effect and cytotoxic activity assessment. Folin-Ciocalteau’s method was used for the measurement of total phenolic content of the extracts. The antioxidant activity was measured by employing three different established testing systems, such as scavenging activity on DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals, reducing power assay and SOD (superoxide dismutase) activity assay. The cytotoxic activity of the extracts were evaluated against three colon cancer cell lines with varying molecular characteristics (HT-29, HCT-15 and HCT-116) by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Results The total phenolic content and antioxidant capabilities differed significantly among the L. indica leaf extracts. A strong correlation between total phenolic content and antioxidant properties was found, indicating that phenolic compounds are the major contributor to the antioxidant properties of these extracts. Among the crude ethanol and its fractionated extracts, fractionated water extract showed significantly the highest total phenolic content and strongest antioxidant effect in all the antioxidant testing systems employed in this study. All the four extracts exert no damage to the selected colon cancer cells. Conclusions The

  3. Phenolic content, antioxidant and antibacterial activity of selected natural sweeteners available on the Polish market.

    PubMed

    Grabek-Lejko, Dorota; Tomczyk-Ulanowska, Kinga

    2013-01-01

    Seventeen natural sweeteners available on the Polish market were screened for total phenolic content, by the Folin-Ciocalteu method, and for antioxidant activity, using the ferric reducing antioxidant power (FRAP) assay and the 2,2'-Azinobis (3-ethylbenzthiazoline-6-sulphonic acid) radical cation decolorization assay (ABTS(·+)). In addition, we analyzed antibacterial activities against Staphylococcus aureus strains: both those susceptible and those resistant to methicillin (MRSA). The results of the study showed that total phenolic content, antioxidant activity and antibacterial activity differ widely among different samples of sweeteners. Phenolic content, expressed as a gallic acid equivalent, ranged from 0 mg kg(-1) in white, refined sugar, xylitol and wheat malt syrup to 11.4 g kg(-1) in sugarcane molasses. Antioxidant activity was lowest in refined white sugar, xylitol, brown beet sugar, liquid fructose, and rape honey; it was average in spelt syrup and corn syrup, and highest in sugar cane, beet molasses, date and barley syrups. Despite the great variety of sweeteners, a strong correlation was noted between the concentration of phenolics and antioxidant properties, as determined by the ABTS(·+) method (r = 0.97) and the FRAP assay (r = 0.77). The strongest antibacterial activity was observed in sugarcane molasses, which was lethal to S. aureus strains at 2 and 4% concentrations in medium for susceptible and MRSA strains respectively. Other sweeteners kill bacteria in 6-15% solutions, whereas some did not show any antibacterial activities against S. aureus strains, even at 20% concentrations. Due to their high antioxidant and antibacterial activities, some of the tested sweeteners have potential therapeutic value as supporting agents in antibiotic therapy.

  4. Estimating water content in an active landfill with the aid of GPR

    SciTech Connect

    Yochim, April; Zytner, Richard G.; McBean, Edward A.; Endres, Anthony L.

    2013-10-15

    Highlights: • Limited information in the literature on the use of GPR to measure in situ water content in a landfill. • Developed GPR method allows measurement of in situ water content in a landfill. • Developed GPR method is appealing to waste management professionals operating landfills. - Abstract: Landfill gas (LFG) receives a great deal of attention due to both negative and positive environmental impacts, global warming and a green energy source, respectively. However, predicting the quantity of LFG generated at a given landfill, whether active or closed is difficult due to the heterogeneities present in waste, and the lack of accurate in situ waste parameters like water content. Accordingly, ground penetrating radar (GPR) was evaluated as a tool for estimating in situ water content. Due to the large degree of subsurface heterogeneity and the electrically conductive clay cap covering landfills, both of which affect the transmission of the electromagnetic pulses, there is much scepticism concerning the use of GPR to quantify in situ water content within a municipal landfill. Two landfills were studied. The first landfill was used to develop the measurement protocols, while the second landfill provided a means of confirming these protocols. GPR measurements were initially completed using the surface GPR approach, but the lack of success led to the use of borehole (BH) GPR. Both zero offset profiling (ZOP) and multiple offset gathers (MOG) modes were tried, with the results indicating that BH GPR using the ZOP mode is the most simple and efficient method to measure in situ water content. The best results were obtained at a separation distance of 2 m, where higher the water content, smaller the effective separation distance. However, an increase in water content did appear to increase the accuracy of the GPR measurements. For the effective separation distance of 2 m at both landfills, the difference between GPR and lab measured water contents were reasonable

  5. Thiamine content and thiaminase activity of ten freshwater stocks and one marine stock of alewives

    USGS Publications Warehouse

    Fitzsimons, J.D.; Williston, B.; Zajicek, J.L.; Tillitt, D.E.; Brown, S.B.; Brown, L.R.; Honeyfield, D.C.; Warner, D.M.; Rudstam, L. G.; Pearsall, W.

    2005-01-01

    Alewives Alosa pseudoharengus contain thiaminase activity that has been implicated in the development of a thiamine deficiency and associated effects in salmonines of the Great Lakes basin. Little is known about the factors that regulate thiaminase activity in alewives. We sampled alewives of uniform size (60-120 mm) during the summer of 1998 from the Gulf of St. Lawrence, seven of New York's Finger Lakes, one inland lake in Ontario, and two Great Lakes to assess possible relationships among thiamine, lipid content, fish abundance, lake morphometry, lake productivity, freshwater residency, and thiaminase activity. Thiaminase activity varied significantly among the 11 locations but was unrelated to thiamine concentration, which did not vary significantly. Alewife thiaminase activity in the Finger Lakes was negatively related to lipid content and positively related to measures of lake size (e.g., area, volume, and maximum depth). Activity in the one marine stock sampled in the Gulf of St. Lawrence was comparable to the highest values observed in the 10 freshwater stocks examined. Variation in alewife thiaminase activity has the potential to affect the extent of a thiamine deficiency associated with salmonines who feed on alewives as well as the viability of their offspring.

  6. Physical activity and cognitive-health content in top-circulating magazines, 2006-2008.

    PubMed

    Price, Anna E; Corwin, Sara J; Friedman, Daniela B; Laditka, Sarah B; Colabianchi, Natalie; Montgomery, Kara M

    2011-04-01

    Physical activity may promote cognitive health in older adults. Popular media play an important role in preventive health communication. This study examined articles discussing associations between physical activity and cognitive health in top-circulating magazines targeting older adults. 42,753 pages of magazines published from 2006 to 2008 were reviewed; 26 articles met inclusion criteria. Explanations regarding the link between physical activity and cognitive health were provided in 57.7% of articles. These explanations were generally consistent with empirical evidence; however, few articles included empirical evidence. Physical activity recommendations were presented in 80.8% of articles; a wide range was recommended (90-300 min of physical activity per wk). Socioeconomic status and education level were not mentioned in the text. Results suggest an opportunity for greater coverage regarding the role of physical activity in promoting cognitive health in popular media. Magazine content would benefit from including more empirical evidence, culturally sensitive content, and physical activity recommendations that are consistent with U.S. guidelines.

  7. Physico-chemical properties, antioxidant activity and mineral contents of pineapple genotypes grown in china.

    PubMed

    Lu, Xin-Hua; Sun, De-Quan; Wu, Qing-Song; Liu, Sheng-Hui; Sun, Guang-Ming

    2014-06-23

    The fruit physico-chemical properties, antioxidant activity and mineral contents of 26 pineapple [Ananas comosus (L.) Merr.] genotypes grown in China were measured. The results showed great quantitative differences in the composition of these pineapple genotypes. Sucrose was the dominant sugar in all 26 genotypes, while citric acid was the principal organic acid. Potassium, calcium and magnesium were the major mineral constituents. The ascorbic acid (AsA) content ranged from 5.08 to 33.57 mg/100 g fresh weight (FW), while the total phenolic (TP) content varied from 31.48 to 77.55 mg gallic acid equivalents (GAE)/100 g FW. The two parameters in the predominant cultivars Comte de Paris and Smooth Cayenne were relative low. However, MD-2 indicated the highest AsA and TP contents (33.57 mg/100 g and 77.55 mg GAE/100 g FM, respectively), and it also showed the strongest antioxidant capacity 22.85 and 17.30 μmol TE/g FW using DPPH and TEAC methods, respectively. The antioxidant capacity of pineapple was correlated with the contents of phenolics, flavonoids and AsA. The present study provided important information for the further application of those pineapple genotypes.

  8. Phenolic Content and Antioxidant Activity during the Development of 'Brookfield' and 'Mishima' Apples.

    PubMed

    Stanger, Mayara C; Steffens, Cristiano A; Soethe, Cristina; Moreira, Marcelo A; do Amarante, Cassandro V T

    2017-05-03

    The aim of this study was to characterize the changes in the contents of total (TPC) and individual (IPC) phenolic compounds, the total antioxidant activity (TAA) in the peel and pulp, and total anthocyanins (TAN) in the peel during the development of the fruits of 'Brookfield' and 'Mishima' apple trees. 'Brookfield' apples were harvested from the 49th to the 138th days after full bloom (DAFB) and 'Mishima' apples from the 45th to the 172th DAFB. In the pulp, the IPC, TPC, and TAA rapidly reduced at 75 and 79 DAFB for the 'Brookfield' and 'Mishima' apples, respectively, and then remained constant until commercial maturity. In the peel of 'Brookfield' apples there was a reduction in the TPC and TAA at 79 DAFB. The quercetin 3-galactoside, epicatechin, and procyanidin B2 contents reduced up to 107 DAFB with a subsequent increase in the values at commercial maturity. In the peel of 'Mishima' apples there was a reduction in the TPC, TAA, epicatechin, and procyanidin B1 and B2 contents at 130 DAFB, with a subsequent increase until commercial maturity. The TAN content in the peel increased during the 2 and 4 weeks prior to commercial maturity for 'Brookfield' and 'Mishima' apples, respectively. In the pulp and peel of both cultivars there was a reduction in the IPC, TPC, and TAA as the development proceeded. On nearing commercial maturity, there was an increase in the contents of quercetin 3-galactoside, epicatechin, procyanidin B2, and TAN in the peel for both cultivars.

  9. Antioxidant activities, metal contents, total phenolics and flavonoids of seven Morchella species.

    PubMed

    Gursoy, Nevcihan; Sarikurkcu, Cengiz; Cengiz, Mustafa; Solak, M Halil

    2009-09-01

    Seven Morchella species were analyzed for their antioxidant activities in different test systems namely beta-carotene/linoleic acid, DPPH, reducing power, chelating effect and scavenging effect (%) on the stable ABTS*(+), in addition to their heavy metals, total phenolic and flavonoid contents. In beta-carotene/linoleic acid system, the most active mushrooms were M. esculenta var. umbrina and M.angusticeps. In the case of DPPH, methanol extract of M. conica showed high antioxidant activity. The reducing power of the methanol extracts of mushrooms increased with concentration. Chelating capacity of the extracts was also increased with the concentration. On the other hand, in 40 microg ml(-1) concentration, methanol extract of M. conica, exhibited the highest radical scavenging activity (78.66+/-2.07%) when reacted with the ABTS*(+) radical. Amounts of seven elements (Cu, Mn, Co, Zn, Fe, Ca, and Mg) and five heavy metals (Ni, Pb, Cd, Cr, and Al) were also determined in all species. M. conica was found to have the highest phenolic content among the samples. Flavonoid content of M. rotunda was also found superior (0.59+/-0.01 microg QEs/mg extract).

  10. Variety and Harvesting Season Effects on Antioxidant Activity and Vitamins Content of Citrus sinensis Macfad.

    PubMed

    Cardeñosa, Vanessa; Barreira, João C M; Barros, Lillian; Arenas-Arenas, Francisco J; Moreno-Rojas, José M; Ferreira, Isabel C F R

    2015-05-07

    Five sweet orange (Citrus sinensis Osbeck) varieties cultivated in Huelva (Spain) and picked at two seasons during two consecutive years, were characterized for their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and vitamin content (vitamin E and vitamin C). The effects induced by sweet orange variety and stage of maturity were comprehensively compared by applying 2-way ANOVA and linear discriminant analysis. The results indicated higher differences in antioxidant activity and vitamin contents in response to the effect of the harvesting season, when compared to the effect of sweet orange variety. Nevertheless, the results observed in 2012 showed less marked differences among the assayed sweet orange varieties. Either way, it might be concluded that oranges sampled in January show the highest antioxidant activity and vitamin contents. Furthermore, concerning the properties evaluated in this work, all sweet orange varieties represent good alternatives, except for Rhode Summer, which would not be the preferable choice as a target to enhance sweet orange overall characteristics.

  11. High isoflavone content and estrogenic activity of 25 year-old Glycine max tissue cultures.

    PubMed

    Federici, Ermanno; Touché, André; Choquart, Sandie; Avanti, Ornella; Fay, Laurent; Offord, Elizabeth; Courtois, Didier

    2003-10-01

    Soy isoflavones are phytoestrogens which have been associated with several health benefits. In the present study, we report the production of isoflavones in a collection of 40 strains of soya cell cultures established in 1975. A large variability in the isoflavone composition was observed and high-producing strains, with an isoflavone content of up to 46.3 mg g(-1) dry wt., were found. In comparison with soybeans, many callus strains had a higher isoflavone concentration (10-40 times) and a different ratio of genistin to daidzin forms. The highest producing strain was transferred to liquid medium in an Erlenmeyer flask and in a 10 l stirred-tank bioreactor where high isoflavone content (7% dry wt.), concentration (880 mg l(-1)) and a maximum productivity estimated to 60 mg l(-1) d(-1) were obtained. We further studied the estrogenic activity of pure compounds compared to plant cell culture extracts in the estrogen-responsive human endometrial Ishikawa cell line. Estrogen was confirmed to be 1000-10,000 times more active than isoflavones. The estrogenic activity of the extracts correlated to their isoflavone content. The activity of the malonyl isoflavones, assessed here for the first time, was lower than the aglycones. Taken together, these results suggest that soya cell cultures can be used as an alternative source to soybeans to provide high concentrations of bioactive isoflavones.

  12. Phenolic contents and antioxidant activities of major Australian red wines throughout the winemaking process.

    PubMed

    Ginjom, Irine R; D'Arcy, Bruce R; Caffin, Nola A; Gidley, Michael J

    2010-09-22

    Three Australian red wine types (Shiraz, Cabernet Sauvignon, and Merlot) were analyzed for antioxidant activity and a range of phenolic component contents using various spectral methods. More than half of the total phenolic compounds were tannins, whereas monomeric anthocyanins and flavonols were present in much lesser amounts (<10%). The evolution of phenolic contents and the respective antioxidant activities in wine samples from all stages of winemaking showed progressive changes toward those of commercial wines. The antioxidant activity of the wines in DPPH and ABTS assays was positively correlated with total phenolic contents and tannins. Comparisons of the three wine varieties based on their individual phenolic component groups and antioxidant activities showed limited differences between the different varieties. However, when all of the variables were combined in a principal component analysis, variety differentiation was observed. The three varieties of red wines all contained similar and high concentrations of antioxidants despite differences in grape variety/maturity and winemaking process, suggesting that related health benefits would accrue from all of the red wines studied.

  13. Antioxidant activity and total phenolic content of Boerhavia elegans (choisy) grown in Baluchestan, Iran

    PubMed Central

    Sadeghi, Zahra; Valizadeh, Jafar; Azyzian Shermeh, Omid; Akaberi, Maryam

    2015-01-01

    Objective: Boerhaavia elegans L. (Nyctaginaceae) is a medicinal plant used for the treatment of kidney disorders, urinary tract disorders and blood purification in Baluch tribe. The aim of present study is to evaluate the antioxidant property of B. elegans species for the first time. Materials and Methods: Different parts (leaf, stem and fruit) of the plant were extracted by using various solvents (water, methanol, chloroform and ethyl acetate) and evaluated for their antioxidant activity using DPPH (2, 2-diphenyl-1 picryl hydrazyl) and FRAP (ferric reducing antioxidant power) methods. In addition, total phenolic content was determined by Folin–Ciocalteu reagent. Results: Antioxidant results were expressed as IC50. The antioxidant power in DPPH and FRAP assay were evaluated as shown in decreasing order: Methanolic extract > Aqueous extract > Ethyl acetate extract > Chloroform extract, for all parts of the plant. In both methods of antioxidant assay and Folin-Ciocalteu method, methanolic extract of leaf exhibited the highest activity and the most phenolic content IC50= 6.85 ppm and 16.41 mg GA/g d w respectively. Total phenolic content had a positive relationship with antioxidant capacity in extracts and there was a high correlation (r=1.00, p<0.01) between antioxidant activities as determined by both antioxidant assays for various parts. Conclusion: The results of the experiments showed that B. elegans extract had significant antioxidant effects. This high antioxidant activity may be linked to phenolic contents of the plant but complementary investigations are suggested in order to determine active elements. PMID:25767751

  14. Overexpression of cotton GhMKK4 enhances disease susceptibility and affects abscisic acid, gibberellin and hydrogen peroxide signalling in transgenic Nicotiana benthamiana.

    PubMed

    Li, Yuzhen; Zhang, Liang; Lu, Wenjing; Wang, Xiuling; Wu, Chang-Ai; Guo, Xingqi

    2014-01-01

    Mitogen-activated protein kinase (MAPK) cascades are involved in plant development, stress responses and hormonal signal transduction. MAPK kinases (MAPKKs), as the key nodes in these cascades, link MAPKs and MAPKK kinases (MAPKKKs). In this study, GhMKK4, a novel group C MAPKK gene from cotton (Gossypium hirsutum), was isolated and identified. Its expression can be induced by various stresses and signalling molecules. The overexpression of GhMKK4 in Nicotiana benthamiana enhanced its susceptibility to bacterial and fungal pathogens, but had no significant effects on salt or drought tolerance. Notably, the overexpressing plants showed increased sensitivity to abscisic acid (ABA) and gibberellin A3 (GA3), and ABA and gibberellin (GA) signalling were affected on infection with Ralstonia solanacearum bacteria. Furthermore, the overexpressing plants showed more reactive oxygen species (ROS) accumulation and stronger inhibition of catalase (CAT), a ROS-scavenging enzyme, than control plants after salicylic acid (SA) treatment. Interestingly, two genes encoding ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (SAMDC), the key enzymes in polyamine synthesis, exhibited reduced R. solanacearum-induced expression in overexpressing plants. These findings broaden our knowledge about the functions of MAPKKs in diverse signalling pathways and the negative regulation of disease resistance in the cotton crop.

  15. Variation in contents of main active components and antioxidant activity in leaves of different pigeon pea cultivars during growth.

    PubMed

    Wei, Zuo-Fu; Jin, Shuang; Luo, Meng; Pan, You-Zhi; Li, Ting-Ting; Qi, Xiao-Lin; Efferth, Thomas; Fu, Yu-Jie; Zu, Yuan-Gang

    2013-10-23

    Pigeon pea is an important and multiuse grain legume crop, and its leaves are a very valuable natural resource. To obtain a high-quality biological resource, it is necessary to choose the excellent cultivar and determine the appropriate harvest time. In this study, the variation in contents of main active components and antioxidant activity in leaves of six pigeon pea cultivars during growth were investigated. The level of each individual active component significantly varied during growth, but with a different pattern, and this variation was different among cultivars. Flavonoid glycosides orientin, vitexin, and apigenin-6,8-di-C-α-L-arabinopyranoside showed two peak values at mid-late and final stages of growth in most cases. Pinostrobin chalcone, longistyline C, and cajaninstilbene acid showed remarkablely higher values at the mid-late stage of growth than at other stages. Pinostrobin had an extremely different variation pattern compared to other active components. Its content was the highest at the earlier stage of growth. Principal component analysis (PCA) revealed that vitexin and apigenin-6,8-di-C-α-L-arabinopyranoside were mainly responsible for distinguishing cultivars analyzed. In a comprehensive consideration, the leaves should preferentially be harvested at the 135th day after sowing when the level of active components and antioxidant activity reached higher values. Cultivars ICP 13092, ICPL 87091, and ICPL 96053 were considered to be excellent cultivars with high antioxidant activity. Our findings can provide valuable information for producing a high-quality pigeon pea resource.

  16. Anthocyanin contents in the seed coat of black soya bean and their anti-human tyrosinase activity and antioxidative activity.

    PubMed

    Jhan, J-K; Chung, Y-C; Chen, G-H; Chang, C-H; Lu, Y-C; Hsu, C-K

    2016-06-01

    The seed coat of black soya bean (SCBS) contains high amount of anthocyanins and shows antioxidant and anti-mushroom tyrosinase activities. The objectives of this study were to analyse the anthocyanins in SCBS with different solvents and to find the relationship between anthocyanin profile with anti-human and anti-mushroom tyrosinase activities. SCBS was extracted with hot water, 50 and 80% ethanol, 50 and 80% acetone and 50 and 80% acidified acetone. Total phenol and total flavonoid contents in the extracts were determined. Anthocyanins in the extracts were analysed using HPLC and LC/MS/MS. A genetically engineered human tyrosinase was used to evaluate the anti-tyrosinase potential of the extracts from SCBS. 80% acetone extract from SCBS obtained the highest total phenol, total flavonoid and cyanidin-3-O-glucoside (C3G) contents among all the extracts, whereas the hot water extract showed the lowest antioxidant contents. Three anthocyanin compounds were found in all the extracts from SCBS, and the analysis of HPLC and LC/MS/MS indicated that they were C3G, delphinidin-3-O-glucoside (D3G) and peonidin-3-O-glucoside (P3G). The ratios of C3G (2.84 mg g(-1) ), D3G (0.34 mg g(-1) ) and P3G (0.35 mg g(-1) ) in 80% acidified acetone extract were 76.6, 9.1 and 9.3%, respectively. All the extracts from SCBS possessed anti-human tyrosinase activity. Moreover, a good correlation was found between the anti-human tyrosinase activities and C3G contents in the extracts. Antioxidants in SCBS also possess anti-human and anti-mushroom tyrosinase activities. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  17. Analysis of the rice mutant dwarf and gladius leaf 1. Aberrant katanin-mediated microtubule organization causes up-regulation of gibberellin biosynthetic genes independently of gibberellin signaling.

    PubMed

    Komorisono, Masahiko; Ueguchi-Tanaka, Miyako; Aichi, Ikuko; Hasegawa, Yasuko; Ashikari, Motoyuki; Kitano, Hidemi; Matsuoka, Makoto; Sazuka, Takashi

    2005-08-01

    Molecular genetic studies of plant dwarf mutants have indicated that gibberellin (GA) and brassinosteroid (BR) are two major factors that determine plant height; dwarf mutants that are caused by other defects are relatively rare, especially in monocot species. Here, we report a rice (Oryza sativa) dwarf mutant, dwarf and gladius leaf 1 (dgl1), which exhibits only minimal response to GA and BR. In addition to the dwarf phenotype, dgl1 produces leaves with abnormally rounded tip regions. Positional cloning of DGL1 revealed that it encodes a 60-kD microtubule-severing katanin-like protein. The protein was found to be important in cell elongation and division, based on the observed cell phenotypes. GA biosynthetic genes are up-regulated in dgl1, but the expression of BR biosynthetic genes is not enhanced. The enhanced expression of GA biosynthetic genes in dgl1 is not caused by inappropriate GA signaling because the expression of these genes was repressed by GA3 treatment, and degradation of the rice DELLA protein SLR1 was triggered by GA3 in this mutant. Instead, aberrant microtubule organization caused by the loss of the microtubule-severing function of DGL1 may result in enhanced expression of GA biosynthetic genes in that enhanced expression was also observed in a BR-deficient mutant with aberrant microtubule organization. These results suggest that the function of DGL1 is important for cell and organ elongation in rice, and aberrant DGL1-mediated microtubule organization causes up-regulation of gibberellin biosynthetic genes independently of gibberellin signaling.

  18. Comparison of phenolic content and antioxidant activity of Actaea racemosa L. and Actaea cordifolia DC.

    PubMed

    Szymczak, Grażyna; Wójciak-Kosior, Magdalena; Sowa, Ireneusz; Zapała, Karolina; Bogucka-Kocka, Anna

    2015-01-01

    Actaea racemosa L. is used as a component of drugs or dietary supplements to alleviate the menopause symptoms. Its biological activity is associated with the presence of phenolic compounds. In our work, the analysis of isoflavones and phenolic acids - caffeic acid (CA), ferulic acid and isoferulic acid (iFA) - both free and bonded in two species of Actaea, was conducted using HPLC-PAD technique. Moreover, the antioxidant effect of extracts from different parts of the investigated plants was determined on the basis of DPPH assay. Significant variation of CA and iFA content was observed. The highest content of CA was found in A. racemosa, while Actaea cordifolia contained the highest amount of iFA. Isoflavones were not found in the investigated plants. The antioxidant activity assay showed the high free radical-scavenging ability of the extracts obtained from different parts of the plant.

  19. Influence of hydroxyl contents on photocatalytic activities of polymorphic titania nanoparticles

    SciTech Connect

    kaewguna, Sujaree; Nolpha, Christopher A.; Lee, Burtrand I.; Wang, Li Q.

    2009-03-15

    Polymorphic titania nanoparticles, prepared by a Water-based Ambient Condition Sol (WACS) process, were post-treated by a Solvent-based Ambient Condition Sol (SACS) process in sec-butanol. All samples were characterized for phase composition, surface area, lattice hydroxyl contamination, and particle morphology by X-ray diffraction, N2 physisorption, FT-IR, solid state Magic Angle Spinning (MAS) 1H NMR and scanning electron microscopy. The resultswerecompared to acommercial titania, Degussa P25. Evaluation of methyl orange degradation under UV irradiation results showed that the lower lattice hydroxyl content in SACS titania nanoparticles enhances photocatalytic activity. As-prepared titania and post-treated SACS samples, which have similar surface areas and crystallinity, were compared in order to prove that the superior photocatalytic activity came from a reduction in lattice hydroxyl content.

  20. Polysaccharides, total flavonoids content and antioxidant activities in different parts of Silybum marianum L. plants

    NASA Astrophysics Data System (ADS)

    Sun, Jing; Li, Xinhua; Yu, Xiaolei

    2017-01-01

    Silybum marianum L. is used for the production of silymarin, a flavonoid utilized for regenerating damaged hepatic tissues. Herein, the total flavonoid content (TFC) and polysaccharides content (PC) in the roots, main stems, leaves, fruit receptacles, and pappi of Silybum marianum were determined. The antioxidant activities of plant ethanol extracts were assessed to validate the medicinal potential of the various plant parts. The pappi exhibited the highest TFC (17.10 mg rutin/g of dry plant material), followed by the fruit receptacles (15.34 mg/g). The PC varied from 3.57±0.23 to 11.02±0.35 mg glucose /g dry plant material; the highest PC was obtained from the roots. At 50 ug/mL, the pappi ethanol extract showed the highest 1, 1-Diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity (69.68%), followed by the roots (66.02%).

  1. The antioxidant activity and polyphenolic contents of different plant seeds extracts.

    PubMed

    Atrooz, Omar M

    2009-08-01

    Different plant seeds extracts of Citrus sinensis, Hordeum sativum, Triticum sativum, Canna indica, Citrullus vulgaris and Capsicum annuum were evaluated for their antioxidant activity by the following methods: 2,2-diphenyl-1-pycril-hydrazyl (DPPH) radical scavenging, reducing power, RBCs hemolysis and linoleic acid oxidation, a long with the determination of total phenolic and flavonoids contents. All the methanolic extracts showed high antioxidant activity and have high contents of phenolic and flavonoid. The Canna indica extract exhibited strong antioxidant as a reducing power and as DPPH radical-scavenging (3.61 absorbance, 87.12%, respectively), while the Hordeum sativum extract exhibited highest inhibitory effect on RBCs hemolysis (59.55%) and the Capsicum annuum extract has highest inhibitory effect on linoleic acid peroxidation (65.06%).

  2. The LS locus of pea encodes the gibberellin biosynthesis enzyme ent-kaurene synthase A.

    PubMed

    Ait-Ali, T; Swain, S M; Reid, J B; Sun, T; Kamiya, Y

    1997-03-01

    Gibberellins (GAs) are hormones required for several aspects of plant development, including internode elongation and seed development in pea (Pisum sativum L.). The first committed step in the GA biosynthesis pathway is the conversion of geranylgeranyl diphosphate (GGDP) to ent-kaurene via copalyl diphosphate (CDP). These two reactions are catalyzed by the cyclases ent-kaurene synthase A (KSA) and ent-kaurene synthase B (KSB), respectively. Previous genetic and biochemical analysis of the GA-responsive ls-1 mutant of pea suggested that GA levels are reduced in a developmental- and organ-specific manner due to reduced GA biosynthesis. Analysis of cellfree enzyme preparations from WT and ls-1 embryos at contact point reveals that ls-1 reduces the activity of KSA but not KSB. To characterize the ls-1 mutation in more detail, a cDNA coding for a pea KSA was cloned and shown to be encoded by the LS locus. The ls-1 mutation results from an intronic G to A substitution that causes impaired RNA splicing. To determine the activity of the KSAs encoded by the LS and ls-1 alleles, a new in vitro assay for combined KSA and KSB activity has been developed using the KSB gene of pumpkin. Using recombinant WT KSA and KSB fusion proteins, GGDP is converted to ent-kaurene in vitro. Based on the sequence of RT-PCR products, three different truncated KSA proteins are predicted to exist in ls-1 plants. The most abundant mutant KSA protein does not possess detectable activity in vitro. Nevertheless, the ls-1 allele is not null and is able to encode at least a partially functional KSA since a more severe is allele has been identified. The ls-1 mutation has played a key role in identifying a role for GAs in pea seed development in the first few days after fertilization, but not in older seeds. KSA expression in seeds is developmentally regulated and parallels overall GA biosynthesis, suggesting that KSA expression may play an important role in the regulation of GA biosynthesis and seed

  3. Overexpression of SlRBZ Results in Chlorosis and Dwarfism through Impairing Chlorophyll, Carotenoid, and Gibberellin Biosynthesis in Tomato

    PubMed Central

    Fan, Mingqin; Gao, Shenghua; Ren, Junling; Yang, Qihong; Li, Hanxia; Yang, Changxian; Ye, Zhibiao

    2016-01-01

    ZFPs play important roles in many biological processes, including plant development, stress response, and phytohormone response. RanBP2-type zinc finger transcription factors have been characterized in animals and humans. However, their functions remain largely unknown in plants. In this study, we identified a RanBP2-type zinc finger protein gene (SlRBZ) in tomato. SlRBZ was constitutively expressed in roots, stems, leaves, flowers, and fruits. The SlRBZ-GFP fused protein was localized in the nucleus. Overexpression of SlRBZ resulted in chlorosis and dwarf phenotypes in tomato. Determination of physiological index showed that chlorophyll, carotenoid, and GAs contents were evidently decreased in transgenic plants. Furthermore, the qRT-PCR and RNA-Seq analyses demonstrated that the transcription of the genes involved in these biosynthesis pathways obviously decreased in SlRBZ-OE plants. In addition, ultrastructural observation by transmission electron microscopy indicated that plastids could not develop into mature chloroplasts with normal chloroplast membrane and thylakoid membrane system in SlRBZ-OE plants. The results suggest that overexpression of SlRBZ may impair the biosynthesis of chlorophyll, carotenoid, and gibberellin through blocking chloroplast development, resulting in chlorosis and dwarfism in tomato. PMID:27446137

  4. Resilience of Penicillium resedanum LK6 and exogenous gibberellin in improving Capsicum annuum growth under abiotic stresses.

    PubMed

    Khan, Abdul Latif; Waqas, Muhammad; Lee, In-Jung

    2015-03-01

    Understanding how endophytic fungi mitigate abiotic stresses in plants will be important in a changing global climate. A few endophytes can produce phytohormones, but their ability to induce physiological changes in host plants during extreme environmental conditions are largely unexplored. In the present study, we investigated the ability of Penicillium resedanum LK6 to produce gibberellins and its role in improving the growth of Capsicum annuum L. under salinity, drought, and heat stresses. These effects were compared with exogenous application of gibberellic acid (GA3). Endophyte treatment significantly increased shoot length, biomass, chlorophyll content, and the photosynthesis rate compared with the uninfected control during abiotic stresses. The endophyte and combined endophyte + GA3 treatments significantly ameliorated the negative effects of stresses compared with the control. Stress-responsive endogenous abscisic acid and its encoding genes, such as zeaxanthin epoxidase, 9-cis-epoxycarotenoid dioxygenase 3, and ABA aldehyde oxidase 3, were significantly reduced in endophyte-treated plants under stress. Conversely, salicylic acid and biosynthesis-related gene (isochorismate synthase) had constitutive expressions while pathogenesis related (PR1 and PR5) genes showed attenuated responses during endophyte treatment under abiotic stresses. The present findings suggest that endophytes have effects comparable to those of exogenous GA3; both can significantly increase plant growth and yield under changing environmental conditions by reprogramming the host plant's physiological responses.

  5. Silencing of the gibberellin receptor homolog, CsGID1a, affects locule formation in cucumber (Cucumis sativus) fruit.

    PubMed

    Liu, Bin; Liu, Xingwang; Yang, Sen; Chen, Chunhua; Xue, Shudan; Cai, Yanling; Wang, Dandan; Yin, Shuai; Gai, Xinshuang; Ren, Huazhong

    2016-04-01

    Gibberellins are phytohormones with many roles, including the regulation of fruit development. However, little is known about the relationship between GA perception and fleshy fruit ontogeny, and particularly locule formation. We characterized the expression of cucumber (Cucumis sativus) GA receptor gene (CsGID1a) using quantitative real-time PCR, in situ hybridization and a promoter::β-glucuronidase (GUS) assay. CsGID1a-RNAi cucumber fruits were observed by dissecting microscope, scanning electron microscopy and transmission electron microscopy. Finally, genome-wide gene expression in young fruits from a control and the RNAi line was compared using a digital gene expression (DGE) analysis approach. The expression pattern of CsGID1a was found to be closely correlated with fruit locule formation, and silencing CsGID1a in cucumber resulted in fruits with abnormal carpels and locules. Overexpression of CsGID1a in the Arabidopsis thaliana double mutant (gid1a gid1c) resulted in 'cucumber locule-like' fruits. The DGE analysis suggested that expression of genes related to auxin synthesis and transport, as well as the cell cycle, was altered in CsGID1a-RNAi fruits, a result that was supported by comparing the auxin content and cellular structures of the control and transgenic fruits. This study demonstrates a previously uncharacterized GA signaling pathway that is essential for cucumber fruit locule formation. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  6. Overexpression of SlRBZ Results in Chlorosis and Dwarfism through Impairing Chlorophyll, Carotenoid, and Gibberellin Biosynthesis in Tomato.

    PubMed

    Fan, Mingqin; Gao, Shenghua; Ren, Junling; Yang, Qihong; Li, Hanxia; Yang, Changxian; Ye, Zhibiao

    2016-01-01

    ZFPs play important roles in many biological processes, including plant development, stress response, and phytohormone response. RanBP2-type zinc finger transcription factors have been characterized in animals and humans. However, their functions remain largely unknown in plants. In this study, we identified a RanBP2-type zinc finger protein gene (SlRBZ) in tomato. SlRBZ was constitutively expressed in roots, stems, leaves, flowers, and fruits. The SlRBZ-GFP fused protein was localized in the nucleus. Overexpression of SlRBZ resulted in chlorosis and dwarf phenotypes in tomato. Determination of physiological index showed that chlorophyll, carotenoid, and GAs contents were evidently decreased in transgenic plants. Furthermore, the qRT-PCR and RNA-Seq analyses demonstrated that the transcription of the genes involved in these biosynthesis pathways obviously decreased in SlRBZ-OE plants. In addition, ultrastructural observation by transmission electron microscopy indicated that plastids could not develop into mature chloroplasts with normal chloroplast membrane and thylakoid membrane system in SlRBZ-OE plants. The results suggest that overexpression of SlRBZ may impair the biosynthesis of chlorophyll, carotenoid, and gibberellin through blocking chloroplast development, resulting in chlorosis and dwarfism in tomato.

  7. Genetic Analysis Reveals That C19-GA 2-Oxidation Is a Major Gibberellin Inactivation Pathway in Arabidopsis[W

    PubMed Central

    Rieu, Ivo; Eriksson, Sven; Powers, Stephen J.; Gong, Fan; Griffiths, Jayne; Woolley, Lindsey; Benlloch, Reyes; Nilsson, Ove; Thomas, Stephen G.; Hedden, Peter; Phillips, Andrew L.

    2008-01-01

    Bioactive hormone concentrations are regulated both at the level of hormone synthesis and through controlled inactivation. Based on the ubiquitous presence of 2β-hydroxylated gibberellins (GAs), a major inactivating pathway for the plant hormone GA seems to be via GA 2-oxidation. In this study, we used various approaches to determine the role of C19-GA 2-oxidation in regulating GA concentration and GA-responsive plant growth and development. We show that Arabidopsis thaliana has five C19-GA 2-oxidases, transcripts for one or more of which are present in all organs and at all stages of development examined. Expression of four of the five genes is subject to feed-forward regulation. By knocking out all five Arabidopsis C19-GA 2-oxidases, we show that C19-GA 2-oxidation limits bioactive GA content and regulates plant development at various stages during the plant life cycle: C19-GA 2-oxidases prevent seed germination in the absence of light and cold stimuli, delay the vegetative and floral phase transitions, limit the number of flowers produced per inflorescence, and suppress elongation of the pistil prior to fertilization. Under GA-limited conditions, further roles are revealed, such as limiting elongation of the main stem and side shoots. We conclude that C19-GA 2-oxidation is a major GA inactivation pathway regulating development in Arabidopsis. PMID:18805991

  8. Total Phenolic Content and Antioxidant Activity of Some Malvaceae Family Species

    PubMed Central

    de Oliveira, Adriana Maria Fernandes; Pinheiro, Lilian Sousa; Pereira, Charlane Kelly Souto; Matias, Wemerson Neves; Gomes, Roosevelt Albuquerque; Chaves, Otemberg Souza; de Souza, Maria de Fátima Vanderlei; de Almeida, Reinaldo Nóbrega; de Assis, Temilce Simões

    2012-01-01

    The antioxidant activity of four species of the Malvaceae family (Sidastrum micranthum (A. St.-Hil.) Fryxell, Wissadula periplocifolia (L.) C. Presl, Sida rhombifolia (L.) E. H. L and Herissantia crispa L. (Brizicky)) were studied using the total phenolic content, DPPH radical scavenging activity and Trolox equivalent antioxidant capacity (TEAC) assays. The antioxidant activity of the crude extract, phases and two isolated flavonoids, kaempferol 3,7-di-O-α-L-rhamnopyranoside (lespedin) and kaempferol 3-O-β-D-(6''-E-p-coumaroil) glucopyranoside (tiliroside) was determined. The results showed that there is a strong correlation between total polyphenol contents and antioxidant activity of the crude extract of Sidastrum micranthum and Wissadula periplocifolia; however, this was not observed between Sida rhombifolia and Herissantia crispa. The ethyl acetate (EaF) phase showed the best antioxidant effect in the total phenolics, DPPH and TEAC assays, followed by the chloroform (CfF) phase, in most species tested. Lespedin, isolated from the EaF phase of W. periplocifolia and H. crispa may not be responsible for the antioxidant activity due to its low antioxidant activity (IC50: DPPH: 1,019.92 ± 68.99 mg/mL; TEAC: 52.70 ± 0.47 mg/mL); whereas tiliroside, isolated from W. periplocifolia, H. crispa and S. micrantum presented a low IC50 value (1.63 ± 0.86 mg/mL) compared to ascorbic acid in the TEAC assay. PMID:26787614

  9. Comparison of total phenolic content and antioxidant activity of Kappaphycus alvarezii from Langkawi and Semporna

    NASA Astrophysics Data System (ADS)

    Mohamed, Norhidayu; Abdullah, Aminah

    2016-11-01

    The total phenolic content and antioxidant activity of Kappaphycus alvarezii obtained from Langkawi, Kedah and Semporna, Sabah were evaluated. The total phenolic content (TPC) of the extracts were determined according to the Folin Ciocalteau method and results were expressed as gallic acid equivalents. The antioxidant activities of the extracts were determined by three methods namely Free Radical Scavenging Activity (DPPH), Ferric Reducing Antioxidant Power (FRAP) and Trolox Equivalent Antioxidant Capacity (TEAC). Both of the TPC and FRAP assays showed that seaweed from Semporna, Sabah significantly (p<0.05) had higher antioxidant activities compared to Langkawi, Kedah one (Semporna's seaweed: 73.25 mg GAE/100g and 16.94 µmol TE/100g, Langkawi's seaweed: 54.35 mg GAE/100g and 10.01 µmol TE/100 g). However, the seaweed from Langkawi (60.93 µmol TE/100g) show higher TEAC value compared to seaweed from Semporna (36.36 µmol TE/100g) but for DPPH assay there was no significant difference (p>0.05) between the samples. Pearson coefficient correlation test, showed that there was a positive correlation (p<0.01) between TPC and antioxidant activity (FRAP assay) (r=0.980) and thus it can be concluded that the phenolic compounds was a contributor of the antioxidant activity in Kappaphycus alvarezii.

  10. Phytochemical screening and evaluation of antioxidant activities of Dracocephalum kotschyi and determination of its luteolin content

    PubMed Central

    Kamali, Mansureh; Khosroyar, Susan; Kamali, Hossein; Ahmadzadeh Sani, Tooba; Mohammadi, Ameneh

    2016-01-01

    Objective: Dracocephalum kotschyi (Lamiaceae family) has been used in traditional medicine for stomach and liver disorders, headache and congestion. In the present study, we have investigated phytochemical properties and antioxidant activities of dichloromethane, ethyl acetate and methanol extracts of D.kotschyi. Material and Methods: Antioxidant activities of extracts were evaluated using the integration of HPLC-DPPH and ferric reducing antioxidant power (FRAP) methods. In addition, the luteolincontent was determined using HPLC method. Results: The highest antioxidant activity was observed for the methanol extract (among the three tested extracts) showing 50% DPPH scavenging activity at 4.85µg/ml as compared to butylated hydroxy toluene (BHT) and ascorbic acid (3.00 µg/ml, 0.97 µg/ml). Also, luteolin was detected in methanol extract; it was identified by comparing its retention time and DAD spectra with standard and it was one of antioxidant components of this plant. In addition, the antioxidant activity of methanol extract was higher than BHT, in FRAP assay. Total phenolic content was in the range of 11.62-22.29 mg Gallic acid /gram of dry extract and flavonoid content was in the range of 3.97-5.042 mg Quercetin/ gram of extract for dichloromethane, ethyl acetate and methanol extracts. The quantity of luteolin in D.kotschyiwas found to be 1061.005 µg/g of dried plant. Conclusion: The results of this investigation indicated that luteolin plays major role in the antioxidant activity of the plant. PMID:27516983

  11. Antioxidant potential, cytotoxic activity and total phenolic content of Alpinia pahangensis rhizomes.

    PubMed

    Phang, Chung-Weng; Malek, Sri Nurestri Abd; Ibrahim, Halijah

    2013-10-01

    Alpinia pahangensis, a wild ginger distributed in the lowlands of Pahang, Malaysia, is used by the locals to treat flatulence. In this study, the antioxidant and cytotoxic activities of the crude aqueous methanol and fractionated extracts of Alpinia pahangensis against five different cancer and one normal cell lines were investigated. The total phenolic content of each extract and its fractions were also quantified. This is the first report on the antioxidant and cytotoxic activities of Alpinia pahangensis extract. In the current study, the crude methanol and fractionated extract of the rhizomes of Alpinia pahangensis were investigated for their antioxidant activity using four different assays namely, the DPPH scavenging activity, superoxide anion scavenging, β-carotene bleaching and reducing power assays whilst their phenolic contents were measured by the Folin-Ciocalteu's method.In vitro neutral red cytotoxicity assay was employed to evaluate the cytotoxic activity against five different cancer cell lines, colon cancer (HCT 116 and HT-29), cervical cancer (Ca Ski), breast cancer (MCF7) and lung cancer (A549) cell lines, and one normal cell line (MRC-5). The extract that showed high cytotoxic activity was further investigated for its chemical constituents by GC-MS (gas chromatography-mass spectrometry) analysis. The ethyl acetate fraction showed the strongest DPPH radical scavenging (0.35 ± 0.094 mg/ml) and SOD activities (51.77 ± 4.9%) whilst the methanol extract showed the highest reducing power and also the strongest antioxidant activity in the β-carotene bleaching assays in comparison to other fractions. The highest phenolic content was found in the ethyl acetate fraction, followed by the crude methanol extract, hexane and water fractions. The results showed a positive correlation between total phenolic content with DPPH radical scavenging capacities and SOD activities. The hexane fraction showed potent cytotoxic effect against KB, Ca Ski and HCT 116 cell

  12. Antioxidant potential, cytotoxic activity and total phenolic content of Alpinia pahangensis rhizomes

    PubMed Central

    2013-01-01

    Background Alpinia pahangensis, a wild ginger distributed in the lowlands of Pahang, Malaysia, is used by the locals to treat flatulence. In this study, the antioxidant and cytotoxic activities of the crude aqueous methanol and fractionated extracts of Alpinia pahangensis against five different cancer and one normal cell lines were investigated. The total phenolic content of each extract and its fractions were also quantified. This is the first report on the antioxidant and cytotoxic activities of Alpinia pahangensis extract. Methods In the current study, the crude methanol and fractionated extract of the rhizomes of Alpinia pahangensis were investigated for their antioxidant activity using four different assays namely, the DPPH scavenging activity, superoxide anion scavenging, β-carotene bleaching and reducing power assays whilst their phenolic contents were measured by the Folin-Ciocalteu’s method. In vitro neutral red cytotoxicity assay was employed to evaluate the cytotoxic activity against five different cancer cell lines, colon cancer (HCT 116 and HT-29), cervical cancer (Ca Ski), breast cancer (MCF7) and lung cancer (A549) cell lines, and one normal cell line (MRC-5). The extract that showed high cytotoxic activity was further investigated for its chemical constituents by GC-MS (gas chromatography–mass spectrometry) analysis. Results The ethyl acetate fraction showed the strongest DPPH radical scavenging (0.35 ± 0.094 mg/ml) and SOD activities (51.77 ± 4.9%) whilst the methanol extract showed the highest reducing power and also the strongest antioxidant activity in the β-carotene bleaching assays in comparison to other fractions. The highest phenolic content was found in the ethyl acetate fraction, followed by the crude methanol extract, hexane and water fractions. The results showed a positive correlation between total phenolic content with DPPH radical scavenging capacities and SOD activities. The hexane fraction showed potent cytotoxic

  13. Effect of Metabolic Stress on Coenzyme Q10 Content in Tissues of Active and Passive Rats.

    PubMed

    Kirbaeva, N V; Sharanova, N E; Baturina, V A; Zhminchenko, V M; Pertsov, S S; Vasil'ev, A V

    2016-09-01

    The dynamics of coenzyme Q10 concentration in the blood plasma, liver, and brain of passive and active rats was studied on the model of metabolic stress. This parameter was shown to differ in rats with various patterns of behavior. Dietary consumption of coenzyme Q10 in doses of 10 and 100 mg/kg body weight was followed by changes in its content in experimental animals.

  14. The Conyza triloba Extracts with High Chlorophyll Content and Free Radical Scavenging Activity Had Anticancer Activity in Cell Lines

    PubMed Central

    El-Sayed, Wael M.; Hussin, Warda A.; Mahmoud, Ahmed A.; AlFredan, Mohamed A.

    2013-01-01

    The discovery of anticancer agents paradigm has been shifted to natural resources to overcome the toxicity of many synthetic agents at early clinical stages. In the present study, the antimutagenic, anticancer, phytochemistry, and free radical scavenging activities of five extracts of Conyza triloba were investigated. Extracts II (water : methanol), III (methylene chloride), and IV (methylene chloride : methanol) had the highest chlorophyll content and the highest superoxide scavenging, and metal chelating activities comparable to that of trolox. They also showed DPPH• scavenging activities better than that of α-tocopherol. Virtually all extracts exerted a strong (>40% reduction) antimutagenic activity against sodium azide and benzopyrene. Extracts II, III, and IV showed a remarkable growth inhibition profile with GI50 of 0.07–0.87 μg for Hepa1c1c7 and H4IIE1, A549, HT29, and PC3 cell lines and totally abated the growth of all cell lines, except for the breast cells, at 0.3–7.0 μg. The present study found a strong correlation between the chlorophyll content of Conyza extracts and their DDPH scavenging, metal chelating, and in vitro cytotoxic and cytostatic activities most probably through triggering apoptosis. This study could offer a platform for future studies and help selecting the vital features that identify the extract with potential anticancer activities. PMID:23781512

  15. Concordance between antioxidant activities and flavonol contents in different extracts and fractions of Cuscuta chinensis.

    PubMed

    Yen, Feng-Lin; Wu, Tzu-Hui; Lin, Liang-Tzung; Cham, Thau-Ming; Lin, Chun-Ching

    2008-05-15

    Chinese herbs employed in traditional Chinese medicine (TCM) have been used for centuries in the practice of medicated diet and dietetic therapy. The seed of Cuscuta chinensis Lam. (Convolvulaceae), a commonly used traditional Chinese herb, is frequently added in Chinese cooking and preparation of refreshments, including porridge and alcoholic beverages, to nourish the human body. In the present study, we compared the antioxidant activities of water and ethanol extracts from the seeds C. chinensis and also of its different organic fractions, including n-hexane, ethyl acetate, n-butanol and organic water, by assessing their DPPH (1,1-diphenyl-2-picryl hydrazine) free radical-scavenging, superoxide anion scavenging, anti-superoxide anion formation and anti-lipid peroxidation abilities. The flavonol contents of all test samples were analyzed by high-performance liquid chromatography with an ultraviolet (HPLC-UV) detector. The results showed that there is a direct correlation of the flavonol content with the antioxidant activities from the extracts and fractions of C. chinensis. Moreover, the ethyl acetate fraction demonstrated significantly better and higher antioxidant effects, and also had a higher flavonol content than had the remaining samples (P<0.05). The water fractions, however, exhibited the weakest antioxidant activity, and had low concentrations of flavonols. Thus, we suggest that the ethanol extract of C. chinensis, but not its water extract, could be used as a dietary nutritional supplement to promote human health and prevent oxidation-related diseases, due to its antioxidant properties.

  16. Factor analysis in optimization of formulation of high content uniformity tablets containing low dose active substance.

    PubMed

    Lukášová, Ivana; Muselík, Jan; Franc, Aleš; Goněc, Roman; Mika, Filip; Vetchý, David

    2017-09-11

    Warfarin is intensively discussed drug with narrow therapeutic range. There have been cases of bleeding attributed to varying content or altered quality of the active substance. Factor analysis is useful for finding suitable technological parameters leading to high content uniformity of tablets containing low amount of active substance. The composition of tabletting blend and technological procedure were set with respect to factor analysis of previously published results. The correctness of set parameters was checked by manufacturing and evaluation of tablets containing 1-10mg of warfarin sodium. The robustness of suggested technology was checked by using "worst case scenario" and statistical evaluation of European Pharmacopoeia (EP) content uniformity limits with respect to Bergum division and process capability index (Cpk). To evaluate the quality of active substance and tablets, dissolution method was developed (water; EP apparatus II; 25rpm), allowing for statistical comparison of dissolution profiles. Obtained results prove the suitability of factor analysis to optimize the composition with respect to batches manufactured previously and thus the use of metaanalysis under industrial conditions is feasible. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Polyphenol content and antioxidative activity in some species of freshly consumed salads.

    PubMed

    Heimler, Daniela; Isolani, Laura; Vignolini, Pamela; Tombelli, Sara; Romani, Annalisa

    2007-03-07

    Ten genotypes belonging to Lactuca sativa, Cicorium intybus, Plantago coronopus, Eruca sativa, and Diplotaxis tenuifolia and used in fresh mixed salads were investigated for their polyphenol contents. Flavonoids and hydroxycinnamic acids were characterized by high-performance liquid chromatography (HPLC)/diode array detection/mass spectrometry. Quercetin, kaempferol, luteolin, apigenin, and crysoeriol derivatives were identified; hydroxycinnamic acids were all caffeoyl derivatives. The total polyphenol content was obtained through the Folin-Ciocalteu test and from the HPLC data. The amounts ranged between 0.9 and 4.7 mg/g fresh weight. The antiradical activity was determined by the reaction with the stable DPPH* radical. The Fe2+ chelating activity was determined with a spectrophotometric test. From the complex of data, a quite complete picture of the characteristics of the vegetables emerges. A cultivated C. intybus cultivar exhibited the highest polyphenol content, while a wild C. intybus genotype exhibited the highest antiradical activity. In every case, the characteristics of the different salads as functional foods have been pointed out.

  18. High phosphorylase activity is correlated with increased potato minituber formation and starch content during extended clinorotation

    NASA Astrophysics Data System (ADS)

    Nedukha, O. M.; Schnyukova, E. I.; Leach, J. E.

    2003-05-01

    The major purpose of these experiments were to investigate growth of potato storage organs and starch synthesis in minitubers at slow horizontal clinorotation (2 rpm), which partly mimics microgravity, and a secondary goal was to study the activity and localization of phosphorylase (EC 2.4.1.1) in storage parenchyma under these conditions. Miniplants of Solanum tuberosum L. (cv Adreta) were grown in culture for 30 days for both the vertical control and the horizontal clinorotation. During long-term clinorotation, an acceleration of minituber formation, and an increase of amyloplast number and size in storage parenchyma cells, as well as increased starch content, was observed in the minitubers. The differences among cytochemical reaction intensity, activity of phosphorylase, and carbohydrate content in storage parenchyma cells of minitubers grown in a horizontal clinostat were established by electron-cytochemical and biochemical methods. It is shown that high phosphorylase activity is correlated with increased starch content during extended clinorotation. The results demonstrate the increase in carbohydrate metabolism and possible accelerated growth of storage organs under the influence of microgravity, as mimicked by clinorotation; therefore, clinorotation can be used as a basis for future studies on mechanisms of starch synthesis under microgravity.

  19. High content analysis of phagocytic activity and cell morphology with PuntoMorph.

    PubMed

    Al-Ali, Hassan; Gao, Han; Dalby-Hansen, Camilla; Peters, Vanessa Ann; Shi, Yan; Brambilla, Roberta

    2017-11-01

    Phagocytosis is essential for maintenance of normal homeostasis and healthy tissue. As such, it is a therapeutic target for a wide range of clinical applications. The development of phenotypic screens targeting phagocytosis has lagged behind, however, due to the difficulties associated with image-based quantification of phagocytic activity. We present a robust algorithm and cell-based assay system for high content analysis of phagocytic activity. The method utilizes fluorescently labeled beads as a phagocytic substrate with defined physical properties. The algorithm employs statistical modeling to determine the mean fluorescence of individual beads within each image, and uses the information to conduct an accurate count of phagocytosed beads. In addition, the algorithm conducts detailed and sophisticated analysis of cellular morphology, making it a standalone tool for high content screening. We tested our assay system using microglial cultures. Our results recapitulated previous findings on the effects of microglial stimulation on cell morphology and phagocytic activity. Moreover, our cell-level analysis revealed that the two phenotypes associated with microglial activation, specifically cell body hypertrophy and increased phagocytic activity, are not highly correlated. This novel finding suggests the two phenotypes may be under the control of distinct signaling pathways. We demonstrate that our assay system outperforms preexisting methods for quantifying phagocytic activity in multiple dimensions including speed, accuracy, and resolution. We provide a framework to facilitate the development of high content assays suitable for drug screening. For convenience, we implemented our algorithm in a standalone software package, PuntoMorph. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Assessment of Tungsten Content on Tertiary Creep Deformation Behavior of Reduced Activation Ferritic-Martensitic Steel

    NASA Astrophysics Data System (ADS)

    Vanaja, J.; Laha, Kinkar

    2015-10-01

    Tertiary creep deformation behavior of reduced activation ferritic-martensitic (RAFM) steels having different tungsten contents has been assessed. Creep tests were carried out at 823 K (550 °C) over a stress range of 180 to 260 MPa on three heats of the RAFM steel (9Cr-W-0.06Ta-0.22V) with tungsten content of 1, 1.4, and 2.0 wt pct. With creep exposure, the steels exhibited minimum in creep rate followed by progressive increase in creep rate until fracture. The minimum creep rate decreased, rupture life increased, and the onset of tertiary stage of creep deformation delayed with the increase in tungsten content. The tertiary creep behavior has been assessed based on the relationship, , considering minimum creep rate () instead of steady-state creep rate. The increase in tungsten content was found to decrease the rate of acceleration of tertiary parameter ` p.' The relationships between (1) tertiary parameter `p' with minimum creep rate and time spent in tertiary creep deformation and (2) the final creep rate with minimum creep rate revealed that the same first-order reaction rate theory prevailed in the minimum creep rate as well as throughout the tertiary creep deformation behavior of the steel. A master tertiary creep curve of the steels has been developed. Scanning electron microscopic investigation revealed enhanced coarsening resistance of carbides in the steel on creep exposure with increase in tungsten content. The decrease in tertiary parameter ` p' with tungsten content with the consequent decrease in minimum creep rate and increase in rupture life has been attributed to the enhanced microstructural stability of the steel.

  1. Fractionation of Gibberellins in plant extracts by reverse phase high performance liquid chromatography

    SciTech Connect

    Jones, M.G.; Metzger, J.D.; Zeevaart, J.A.D.

    1980-02-01

    In studies on endogenous plant gibberellins (GAs), reverse phase (Bondapak C/sub 18/) high performance liquid chromatography (HPLC) has proved to be a useful method for the fractionation of plant extracts. The behavior of 18 authentic GAs in such a chromatographic system is described. The main factors determining chromatographic behavior are the degree and the position of hydroxylation of the GA. As an illustration of the use of reverse phase HPLC, the endogeneous GAs of immature seeds of Pharbitis nil L., strain Violet, were reinvestigated. The presence of gibberellins A/sub 3/, A/sub 5/, A/sub 17/, A/sub 20/, and A/sub 29/ was confirmed by gas-liquid chromatography-mass spectrometry. In addition, two other GAs, A/sub 19/ and A/sub 44/, were also identified in extracts of this material.

  2. Sensitivity of Female Inbreds of Cucumis sativus to Sex Reversion by Gibberellin.

    PubMed

    Shifriss, O; George, W L

    1964-03-27

    Two female inbred cucumbers were developed by substituting gene Acr for acr in the genetic backgrounds of the monoecious races Marketer and Tokyo, which exhibit weak and strong male tendency respectively. Marketer females are resistant and Tokyo females are sensitive to sex reversion in response to treatments with gibberellin A(3). Resistance and sensitivity of this type appear to depend upon the genetic system which controls sex tendency.

  3. Arabidopsis ent-kaurene oxidase catalyzes three steps of gibberellin biosynthesis.

    PubMed

    Helliwell, C A; Poole, A; Peacock, W J; Dennis, E S

    1999-02-01

    The Arabidopsis GA3 cDNA was expressed in yeast (Saccharomyces cerevisiae) and the ability of the transformed yeast cells to metabolize ent-kaurene was tested. We show by full-scan gas chromatography-mass spectrometry that the transformed cells produce ent-kaurenoic acid, and demonstrate that the single enzyme GA3 (ent-kaurene oxidase) catalyzes the three steps of gibberellin biosynthesis from ent-kaurene to ent-kaurenoic acid.

  4. High-content fluorescent-based assay for screening activators of DNA damage checkpoint pathways.

    PubMed

    Bin Zhang; Xiubin Gu; Uppalapati, Uma; Ashwell, Mark A; Leggett, David S; Li, Chiang J

    2008-07-01

    Activation of DNA damage checkpoint pathways, including Chk2, serves as an anticancer barrier in precancerous lesions. In an effort to identify small-molecule activators of Chk2, the authors developed a quantitative cell-based assay using a high-content analysis (HCA) platform. Induction of phosphorylated Chk2 was evaluated using several different parameters, including fold induction, Kolmogorov-Smirnov score, and percentage of positively stained cells. These measurements were highly correlated and provided an accurate method for compound ranking/binning, structure-activity relationship studies, and lead identification. Screening for Chk2 activators was undertaken with a target-focused library and a diversified library from ArQule chemical space. Several compounds exhibited submicromolar EC( 50) values for phosphorylated Chk2 induction. These compounds were further analyzed for Chk2-dependent cytotoxicity, as assessed through a high-content cell death assay in combination with siRNA silencing of Chk2 expression. Several compounds were identified and showed specific inhibition or lethality in a target-dependent manner. Therefore, identification of DNA damage checkpoint pathway activators by HCA is an attractive approach for discovering the next generation of targeted cancer therapeutics.

  5. Total Phenolic Content and Antioxidant Activity of Mycelial Extracts from the Medicinal Fungus Paecilomyces hepiali (Ascomycetes).

    PubMed

    Jiang, Lan; Li, Yi; Wang, Wen-Jing; Imoulan, Abdessamad; Yao, Yi-Jian

    2017-01-01

    Paecilomyces hepialid, a fungus originating in the Tibetan Plateau, has been used as a substitute for Ophiocordyceps sinensis because the primary chemical compounds and pharmacological effects of P. hepialid are similar to those of O. sinensis. P. hepialid has been developed into a dietary supplement and pharmaceutical products. The antioxidant activity of extracts using 2 solvents (water and ethanol) from mycelia obtained from 2 cultivation modes (solid-state and submerged cultivation) were evaluated in this study. Four strains of P. hepialid obtained from Qinghai, Sichuan, and Yunnan Provinces were included; the total phenolic content and in vitro antioxidant activity of mycelial extracts were compared. The total phenolic content and antioxidant activity of strains were found to be affected by the cultivation mode and extraction solvent. The ethanol extracts of solid-state cultivation of strain 2138, obtained from Sichuan Province, exhibited the highest antioxidant activity. The results showed that different strains might require different cultivation modes and extraction solvents for better antioxidant activity. However, solid-state cultivation and ethanol extraction are generally recommended based on the analyses conducted. Strain 2138 may be a good candidate for the purpose of producing functional foods. The results suggest that strain selection is important when P. hepialid is used to manufacture pharmaceutical products.

  6. Effects of processing steps on the phenolic content and antioxidant activity of beer.

    PubMed

    Leitao, Céline; Marchioni, Eric; Bergaentzlé, Martine; Zhao, Minjie; Didierjean, Luc; Taidi, Behnam; Ennahar, Saïd

    2011-02-23

    A new analytical method (liquid chromatography-antioxidant, LC-AOx) was used that is intended to separate beer polyphenols and to determine the potential antioxidant activity of these constituents after they were allowed to react online with a buffered solution of the radical cation 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(•+)). Using the LC-AOx method, it was possible to demonstrate that the extent of the antioxidant activity was very much dependent on the phenolic compound considered. The method was also applied to the analysis of beer extracts and allowed the evaluation of their antioxidant activity at different steps of beer processing: brewing, boiling, and fermentation. This study showed that the total antioxidant activity remained unchanged throughout beer processing, as opposed to the polyphenolic content, which showed a 3-fold increase. Hopping and fermentation steps were the main causes of this increase. However, the increase measured after fermentation was attributed to a better extraction of polyphenols due to the presence of ethanol, rather than to a real increase in their content. Moreover, this method allowed the detection of three unknown antioxidant compounds, which accounted for 64 ± 4% of the total antioxidant activity of beer and were individually more efficient than caffeic acid and epicatechin.

  7. Spatial distribution of total phenolic content, enzymatic activities and browning in white yam (Dioscorea rotundata) tubers.

    PubMed

    Graham-Acquaah, Seth; Ayernor, George Sodah; Bediako-Amoa, Betty; Saalia, Firibu Kwesi; Afoakwa, Emmanuel Ohene

    2014-10-01

    Browning in raw and processed yams resulting from enzymes, polyphenol oxidase (PPO) and peroxidase (POD), activities is a major limitation to the industrial utilization of Dioscorea varieties of yams. Two elite cultivars of D. rotundata species were selected to study the spatial distribution of total phenols and enzymes (PPO and POD) activities. The intensities of tissue darkening in fresh yam chips prepared from the tuber sections of cultivars during frozen storage were also studied. Total phenolic content was observed to be highest in the head and mid sections of the cultivars than at the tail end. PPO activity did not have any specific distribution pattern whereas POD activity was found to be more concentrated in the head than in the middle and tail regions. Browning was found to be most intense in the head regions of the two cultivars studied; and was observed to correlate with total phenol and dry matter contents of tubers. Between the two enzymes, POD activity appeared to be more related to browning than PPO.

  8. Antimicrobial and Antioxidant Activities of Bauhinia racemosa Lam. and Chemical Content

    PubMed Central

    Rashed, Khaled; Butnariu, Monica

    2014-01-01

    Methanol 70% extract of Bauhinia racemosa aerial parts was tested for antimicrobial activity against different bacterial and fungal strains and for antioxidant activity and also total content of polyphenols with phytochemical analysis of the extract was determined. The results have showed that the extract has a significant antimicrobial activity, it inhibited the growth of Bacillus subtilis and also it was highly active against Candida albicans suggesting that it can be used in the treatment of fungal infections. The extract has a good antioxidant activity, it has shown high values of the trolox equivalent antioxidant capacity and polyphenol content while it has shown a lower value of oxygen radical absorbance capacity. Phytochemical analysis has shown that it has interesting phytochemical bioconstituents, include flavonoids, tannins and others, and the deep phytochemical study results in the isolation of methyl gallate, gallic, kaempferol, quercetin, querection 3–O–α–rhamnoside, kaempferol 3–O–β–glucoside, myricetin–3–O–β– glucoside, querection–3–O–rutinoside (Rutin). All compounds were identified by different spectroscopic analyses (UV, 1H–NMR, 13C–NMR) and Mass Spectrometry (MS). PMID:25276210

  9. Boron deficiency causes a drastic decrease in nitrate content and nitrate reductase activity, and increases the content of carbohydrates in leaves from tobacco plants

    PubMed

    Camacho-Cristobal; Gonzalez-Fontes

    1999-10-01

    Tobacco (Nicotiana tabacum L.) plants were used to study connections between deficiency in boron and nitrate reduction. Boron deficiency caused a substantial decrease in shoot and, particularly, root weights that resulted in a notably high shoot/root ratio in comparison to boron-sufficient plants. One of the most important effects caused by boron deficiency was the strong decrease in leaf nitrate content. Leaf contents of magnesium, calcium and, especially, potassium also declined under this deficiency, but nitrate content decreased in a higher proportion than these cations. Nitrate reductase (EC 1.6.6.1) activity of boron-deficient plants declined from the beginning of the light period; this decline did not occur in boron-sufficient plants. This fact could be attributed to the faster decrease in transcript levels of Nia, the nitrate reductase structural gene, during the light period in boron-deficient plants. Leaf protein content of boron-deficient plants also declined in the course of light periods. Boron deficiency caused an appreciable accumulation of hexoses and sucrose in leaves. This build-up of soluble sugars might correct the osmotic imbalance elicited by the low content of nitrate and cations in plants subjected to boron deficiency. Boron-deficient plants had much higher starch contents than boron-sufficient ones, and there was an inverse relationship between the contents of nitrate and starch in leaves.

  10. An investigation of the impact of selected prereading activities on student content learning through laboratory activities

    NASA Astrophysics Data System (ADS)

    Kass, Jesse (Shaya)

    This study investigated whether two prereading activities impacted student learning from hands-on science activities. The study was based on constructivist learning theory. Based on the work of Piaget, it was hypothesized that students who activated prior knowledge would learn more from the activities. Based on the work of Vygotsky it was hypothesized that students who talk more and write more would learn more from the activity. The K-W-L chart and anticipation guide strategies were used with eighth grade students at Graves Middle School in Whittier, California before learning about levers and convection currents. D. M. Ogle (1986) created the three-column K-W-L chart to have students activate prior knowledge. In the first column, the students write what they already know about a subject, in the second column, the students write what they want to know about the subject, and the students complete the third column after learning about a subject by writing answers to the questions that they asked in the second column. Duffelmeyer (1994) created the anticipation guide based on Herber's (1978) reasoning guide. In the anticipation guide, the teacher creates three or four sentences that convey the major ideas of the topic and the students either agree or disagree with the statements. After learning about the topic, students revisit their answers and decide if they were correct or incorrect and they must defend their choices. This research used the Solomon (1947) four-square design and compared both the experimental groups to a control group that simply discussed the concepts before completing the activity. The research showed no significant difference between the control group and either of the treatment groups. The reasons for the lack of significant differences are considered. It was hypothesized that since the students were unfamiliar with the prereading activities and did not have much experience with using either writing-to-learn or talking-to-learn strategies, the

  11. Effects of abscisic acid, gibberellin, ethylene and their interactions on production of phenolic acids in salvia miltiorrhiza bunge hairy roots.

    PubMed

    Liang, Zongsuo; Ma, Yini; Xu, Tao; Cui, Beimi; Liu, Yan; Guo, Zhixin; Yang, Dongfeng

    2013-01-01

    Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants because of its excellent performance in treating coronary heart disease. Phenolic acids mainly including caffeic acid, rosmarinic acid and salvianolic acid B are a group of active ingredients in S. miltiorrhiza. Abscisic acid (ABA), gibberellin (GA) and ethylene are three important phytohormones. In this study, effects of the three phytohormones and their interactions on phenolic production in S. miltiorrhiza hairy roots were investigated. The results showed that ABA, GA and ethylene were all effective to induce production of phenolic acids and increase activities of PAL and TAT in S. miltiorrhiza hairy roots. Effects of phytohormones were reversed by their biosynthetic inhibitors. Antagonistic actions between the three phytohormones played important roles in the biosynthesis of phenolic acids. GA signaling is necessary for ABA and ethylene-induced phenolic production. Yet, ABA and ethylene signaling is probably not necessary for GA3-induced phenolic production. The complex interactions of phytohormones help us reveal regulation mechanism of secondary metabolism and scale-up production of active ingredients in plants.

  12. Metabolism of Tritiated Gibberellin A9 by Shoots of Dark-grown Dwarf Pea, cv. Meteor 1

    PubMed Central

    Railton, Ian D.; Durley, Richard C.; Pharis, Richard P.

    1974-01-01

    Tritium-labeled gibberellin A9 (3H-GA9) was metabolized by etiolated shoots of dwarf pea (Pisum sativum cv. Meteor) to GA20, GA10, 2,3-dihydro-GA31, and a number of highly polar, acidic GA-like substances. Identifications were made by gasliquid radiochromatography and combined gas chromatography-mass spectrometry. Kinetic studies showed that GA30 and 2,3-dihydro-GA31 were produced within 5 hours following 3H-GA9 application to pea shoots. The polar GA-like substances were produced between 5 and 10 hours after 3H-GA9 application. Levels of GA10 increased with time, and since no GA10 was produced during the purification procedures, GA10 was, in all probability, produced from 3H-GA9 within the plant tissue. The radioactive interconversion products produced by pea from 3H-GA9 have chromatographic properties similar to biologically active GA-like substances present in etiolated shoots of dwarf pea. Large scale applications of 3H-GA9 with very low specific activity to etiolated pea shoots showed that the radioactivity of the interconversion products was correlated exactly with biological activity as assayed by dwarf rice (Oryza sativa cv. Tan-ginbozu). PMID:16658838

  13. Changes of Endogenous Gibberellin-like Substances with Sex Reversal of the Apical Inflorescence of Corn 1

    PubMed Central

    Rood, Stewart B.; Pharis, Richard P.; Major, David J.

    1980-01-01

    In developing apical meristems of corn, the level of acidic, ethyl acetate-soluble gibberellin (GA)-like substances increased to a maximum of 108 micrograms GA3-equivalents per kilogram dry weight of tissue at inflorescence initiation, and then fell rapidly. At anthesis, only a trace (0.2 microgram per kilogram) of GA-like activity remained in the apical (male) inflorescences, whereas moderate activity (32 micrograms per kilogram), mostly of a nonpolar nature, was present in lateral, female, inflorescences. A sex reversal of the apical inflorescence, from male to female, was elicited by reducing the ambient light intensity. Higher levels of GA-like substances, particularly those eluting from a SiO2 partition column in the nonpolar region, were observed at all harvests in the reverting meristems; levels increased to 180 micrograms per kilogram at inflorescence initiation, then dropped to 122 micrograms per kilogram in the apical (female), reverted meristems. This increase in endogenous GA-like activity with reversion to the female inflorescence is consistent with observations that (a) reversion can be obtained with exogenous application of GA3 and (b) maleness is enhanced in GA-deficient mutants of maize. Endogenous GAs may thus play a key role in the control of sexuality of corn. Images PMID:16661527

  14. Corrections for volume hydrogen content in coal analysis by prompt gamma neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Salgado, J.; Oliveira, C.

    1992-05-01

    Prompt gamma neutron activation analysis, PGNAA, is a useful technique to determine the elemental composition of bulk samples in on-line measurements. Monte Carlo simulation studies performed in bulk coals of different compositions for given sample size and geometry have shown that both the gamma count rate for hydrogen and the gamma count rate per percent by weight for an arbitrary element due to (n, γ) reactions depend on the volume hydrogen content, being independent of coal composition. Experimental results using a 252Cf neutron source surrounded by a lead cylinder were obtained for nine different coal types. These show that the γ-peak originated by (n, n' γ) reactions in the lead shield depends on the sample density. Assuming that the source intensity is constant, this result enables the measurement of the coal bulk density. Taking into account the results just described, the present paper shows how the γ-peak intensities can be corrected for volume hydrogen content in order to obtain the percent by weight contents of the coal. The density is necessary to convert the volume hydrogen in percent by weight content and to calculate the bulk sample weight.

  15. Early Local Activity in Temporal Areas Reflects Graded Content of Visual Perception

    PubMed Central

    Tagliabue, Chiara F.; Mazzi, Chiara; Bagattini, Chiara; Savazzi, Silvia

    2016-01-01

    In visual cognitive neuroscience the debate on consciousness is focused on two major topics: the search for the neural correlates of the different properties of visual awareness and the controversy on the graded versus dichotomous nature of visual conscious experience. The aim of this study is to search for the possible neural correlates of different grades of visual awareness investigating the Event Related Potentials to reduced contrast visual stimuli whose perceptual clarity was rated on the four-point Perceptual Awareness Scale. Results revealed a left centro-parietal negative deflection (Visual Awareness Negativity; VAN) peaking at 280–320 ms from stimulus onset, related to the perceptual content of the stimulus, followed by a bilateral positive deflection (Late Positivity; LP) peaking at 510–550 ms over almost all electrodes, reflecting post-perceptual processes performed on such content. Interestingly, the amplitude of both deflections gradually increased as a function of visual awareness. Moreover, the intracranial generators of the phenomenal content (VAN) were found to be located in the left temporal lobe. The present data thus seem to suggest (1) that visual conscious experience is characterized by a gradual increase of perceived clarity at both behavioral and neural level and (2) that the actual content of perceptual experiences emerges from early local activation in temporal areas, without the need of later widespread frontal engagement. PMID:27199809

  16. Phytochemicals Content, Antioxidant Activity and Acetylcholinesterase Inhibition Properties of Indigenous Garcinia parvifolia Fruit

    PubMed Central

    Ali Hassan, Siti Hawa; Fry, Jeffrey R.

    2013-01-01

    Garcinia parvifolia belongs to the same family as mangosteen (Garcinia mangostana), which is known locally in Sabah as “asam kandis” or cherry mangosteen. The present study was conducted to determine the phytochemicals content (total phenolic, flavonoid, anthocyanin, and carotenoid content) and antioxidant and acetylcholinesterase inhibition activity of the flesh and peel of G. parvifolia. All samples were freeze-dried and extracted using 80% methanol and distilled water. For the 80% methanol extract, the flesh of G. parvifolia displayed higher phenolic and flavonoid contents than the peel, with values of 7.2 ± 0.3 mg gallic acid equivalent (GAE)/g and 5.9 ± 0.1 mg rutin equivalent (RU)/g, respectively. Anthocyanins were detected in the peel part of G. parvifolia but absent in the flesh. The peel of G. parvifolia displayed higher total carotenoid content as compared to the flesh part with the values of 17.0 ± 0.3 and 3.0 ± 0.0 mg β-carotene equivalents (BC)/100 g, respectively. The free-radical scavenging, ferric reducing, and acetylcholinesterase inhibition effect of the flesh were higher as compared to the peel in both extracts. These findings suggested that the edible part of G. parvifolia fruit has a potential as a natural source of antioxidant and anti-Alzheimer's agents. PMID:24288662

  17. Phenolic content, antioxidant activity and effective compounds of kumquat extracted by different solvents.

    PubMed

    Lou, Shyi-Neng; Lai, Yi-Chun; Hsu, Ya-Siou; Ho, Chi-Tang

    2016-04-15

    The total phenolic and flavonoid content of extracts from peel of kumquat were higher than those from pulp, and those extracted from immature kumquat were higher than those from mature kumquat. The highest levels of phenolic and flavonoid content were obtained in hot water extracts. The flavonoids of kumquat extracted from hot water were mainly soluble conjugated compounds, including C-glycosides, such as 3',5'-di-C-β-glucopyranosylphloretin (DGPP), acacetin 8-C-neohesperidoside (margaritene), acacetin 6-C-neohesperidoside (isomargaritene), apigenin 8-C-neohesperidoside, and O-glycosides, such as acacetin 7-O-neohesperidoside (fortunellin), isosakuranetin 7-O-neohesperidoside (poncirin) and apigenin 7-O-neohesperidoside (rhoifolin). A positive relationship existed between total phenolic content and DPPH scavenging potency (p<0.001). Total flavonoid content showed a similar correlation (p<0.001) to DPPH scavenging potency. The effective flavonoids contributing to antioxidant activity were DGPP and apigenin 8-C-neohesperidoside, which could be extracted in high amounts, by hot water at 90°C, from immature kumquat peel. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Phytochemicals content, antioxidant activity and acetylcholinesterase inhibition properties of indigenous Garcinia parvifolia fruit.

    PubMed

    Ali Hassan, Siti Hawa; Fry, Jeffrey R; Abu Bakar, Mohd Fadzelly

    2013-01-01

    Garcinia parvifolia belongs to the same family as mangosteen (Garcinia mangostana), which is known locally in Sabah as "asam kandis" or cherry mangosteen. The present study was conducted to determine the phytochemicals content (total phenolic, flavonoid, anthocyanin, and carotenoid content) and antioxidant and acetylcholinesterase inhibition activity of the flesh and peel of G. parvifolia. All samples were freeze-dried and extracted using 80% methanol and distilled water. For the 80% methanol extract, the flesh of G. parvifolia displayed higher phenolic and flavonoid contents than the peel, with values of 7.2 ± 0.3 mg gallic acid equivalent (GAE)/g and 5.9 ± 0.1 mg rutin equivalent (RU)/g, respectively. Anthocyanins were detected in the peel part of G. parvifolia but absent in the flesh. The peel of G. parvifolia displayed higher total carotenoid content as compared to the flesh part with the values of 17.0 ± 0.3 and 3.0 ± 0.0 mg β-carotene equivalents (BC)/100 g, respectively. The free-radical scavenging, ferric reducing, and acetylcholinesterase inhibition effect of the flesh were higher as compared to the peel in both extracts. These findings suggested that the edible part of G. parvifolia fruit has a potential as a natural source of antioxidant and anti-Alzheimer's agents.

  19. Effect of cooking methods on antioxidant activity and nitrate content of selected wild Mediterranean plants.

    PubMed

    Boari, Francesca; Cefola, Maria; Di Gioia, Francesco; Pace, Bernardo; Serio, Francesco; Cantore, Vito

    2013-11-01

    Wild edible plants (WEP), traditionally consumed in the Mediterranean diet, are considered a rich source of natural antioxidants but can also accumulate significant amount of nitrates. Most WEP are cooked before consumption, therefore, a study was conducted to evaluate the effects of boiling, steaming and microwave cooking processes on the total antioxidant activity (TAA) and nitrate content of eight common WEP. Boiling caused the highest losses of TAA, resulting in a reduction of the TAA on dry weight (DW) basis ranging from 5.5% in Beta vulgaris up to 100% in Urtica dioica. Steaming and microwaving produced the highest increase of TAA on DW basis in Helminthotheca echioides (249.7%) and Taraxacum officinale (60.7%). Boiling caused the highest reduction of nitrate content in all species excluding Asparagus acutifolius that maintained almost unvaried its already low nitrate content. These results suggest that cooking has not always negative effect on product quality, since in certain cases, it may even enhance the nutritional value of WEP by increasing their TAA and reducing the nitrate content.

  20. [Evaluation of content uniformity of tablets with a low content of the active ingredient with a narrow therapeutic index].

    PubMed

    Muselík, Jan; Franc, Aleš

    2012-12-01

    A short time ago there was a discussion about the use of NTI drugs such as warfarin. In the treatment by generic drugs some medical complications and deaths due to occult bleeding were retrospectively monitored. As a result of these observations, the generic substitutions with tablets containing warfarin were banned in the U.S. as there was a belief that generics have different pharmacokinetics. But a subsequent research found that different plasma levels are not due to generic drugs, but they are caused by different individual responses of the organism and especially by not uniform contents of warfarin in individual tablets. The different contents are caused by the method of direct compression where there is no granulation of the tablet blend before compressing. The method of direct compression, however, is very convenient in terms of time, technological feasibility and cost of cure. This report seeks to map the problems of direct compression in the production of tablets containing warfarin, concrete examples showing the relationships between selected parameters and the content uniformity of dosage form. Specifically, it is the influence of the density fillers and addition of the lubricant in various stages of mixing. On the basis of the application of statistical criteria according to the requirements of the FDA for the manufacture of tablets and with the use of the specific parameters of raw materials, the study has demonstrated that the technology of direct compression containing warfarin results not only in safe pharmacotherapy, but it also saves time, materials and cost of manufactured drugs.

  1. In vitro antibacterial, antioxidant activity and total phenolic content of some essential oils.

    PubMed

    Srivastava, Upma; Ojha, Swati; Tripathi, N N; Singh, Pooja

    2015-11-01

    In vitro antibacterial activity of 16 essential oils was investigated by disc diffusion method against two Gram positive bacteria Bacillus subtilis and Staphylococcus aureus and two Gram negative bacteria, Shigella flexneri and Escherichia coli. Oils of Cymbopogon citratus and Ocimum basilicum showed highest antibacterial activity. Gram positive bacteria were found to be more sensitive than Gram negative. Antioxidant activities were tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and ABTS radical cation decolourization assay while Folin-Ciocalteu method was used to determine the total phenolic content. In DPPH assay, highest antioxidant activity was observed in 0. basilicum oil followed by Azeratum conyzoides, A. marmelos and C. citratus, with percent inhibition and IC50 value ranging from 66.11-71.93% and 14.10-17.92 µl ml(-1) respectively. In ABTS assay, similar results were obtained but with higher percent inhibition which ranged from 67.48-76.23% and lower IC50 value (12.12-17.21 µ ml(-1)). Moreover, radical scavenging activity of essential oils was lower than that observed for the synthetic antioxidant BHA and BHT. The total phenolic content of the essential oils as GAE in mg 100 µl(-1) of EO was found to be highest in O. basilicum (0.406) oil followed byA. conyzoides (0.322), A. marmelos (0.238) and C. citratus (0.231). The results provide evidence that the oils of C. citratus and O. basilicum can be further commended for treatment of infections caused by these bacterial pathogens and are potential source of natural antioxidants having appreciable amount of total phenolic content.

  2. Activity, content, contributors, and influencers of the twitter discussion on urologic oncology.

    PubMed

    Borgmann, Hendrik; Loeb, Stacy; Salem, Johannes; Thomas, Christian; Haferkamp, Axel; Murphy, Declan G; Tsaur, Igor

    2016-09-01

    To analyse the activity, content, contributors, and influencers of the Twitter discussion on urologic oncology. We performed a comprehensive quantitative and qualitative Twitter analysis for the hashtags #prostatecancer, #bladdercancer, #kidneycancer, and #testicularcancer. Symplur was used to analyse activity over different time periods and the top influencers of the Twitter discussion. Tweet Archivist and Twitonomy analysis tools were used to assess characteristics of content and contributors. Twitter discussion on urologic oncology in 2014 contained 100,987 tweets created by 39,326 participants. Mean monthly tweet activity was 6,603±2,183 for #prostatecancer, 866±923 for #testicularcancer, 457±477 for #bladdercancer and 401±504 for #kidneycancer. Twitter activity increased by 41% in 2013 and by 122% in 2014. The content analysis detected awareness, cancer, and risk as frequently mentioned words in urologic oncology tweets. Prevalently used related hashtags were the general hashtag #cancer, awareness hashtags, and the respective cancer/urology tag ontology hashtags. Contributors originated from 41 countries on 6 continents and had a mean of 5,864±4,747 followers. They tweeted from platforms on exclusively mobile devices (39%) more frequently than from desktop devices (29%). Health care organizations accounted for 58% of the top influencers in all cancers. The largest proportion of physicians were among the #prostatecancer and #kidneycancer (each 9%) influencers and individual contributors were most frequent in the discussion on #kidneycancer (57%) and #testicularcancer (50%). There is a significant and growing activity in the Twitter discussion on urologic oncology, particularly on #prostatecancer. The Twitter discussion is global, social, and mobile, and merits attention of stakeholders in health care as a promising communication tool. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Interactions between ethylene, gibberellins, and brassinosteroids in the development of rhizobial and mycorrhizal symbioses of pea

    PubMed Central

    Foo, Eloise; McAdam, Erin L.; Weller, James L.; Reid, James B.

    2016-01-01

    The regulation of arbuscular mycorrhizal development and nodulation involves complex interactions between the plant and its microbial symbionts. In this study, we use the recently identified ethylene-insensitive ein2 mutant in pea (Pisum sativum L.) to explore the role of ethylene in the development of these symbioses. We show that ethylene acts as a strong negative regulator of nodulation, confirming reports in other legumes. Minor changes in gibberellin1 and indole-3-acetic acid levels in ein2 roots appear insufficient to explain the differences in nodulation. Double mutants produced by crosses between ein2 and the severely gibberellin-deficient na and brassinosteroid-deficient lk mutants showed increased nodule numbers and reduced nodule spacing compared with the na and lk single mutants, but nodule numbers and spacing were typical of ein2 plants, suggesting that the reduced number of nodules in na and lk plants is largely due to the elevated ethylene levels previously reported in these mutants. We show that ethylene can also negatively regulate mycorrhizae development when ethylene levels are elevated above basal levels, consistent with a role for ethylene in reducing symbiotic development under stressful conditions. In contrast to the hormone interactions in nodulation, ein2 does not override the effect of lk or na on the development of arbuscular mycorrhizae, suggesting that brassinosteroids and gibberellins influence this process largely independently of ethylene. PMID:26889005

  4. Translatome and metabolome effects triggered by gibberellins during rosette growth in Arabidopsis

    PubMed Central

    Ribeiro, Dimas M.; Araújo, Wagner L.; Fernie, Alisdair R.; Schippers, Jos H. M.; Mueller-Roeber, Bernd

    2012-01-01

    Although gibberellins (GAs) are well known for their growth control function, little is known about their effects on primary metabolism. Here the modulation of gene expression and metabolic adjustment in response to changes in plant (Arabidopsis thaliana) growth imposed on varying the gibberellin regime were evaluated. Polysomal mRNA populations were profiled following treatment of plants with paclobutrazol (PAC), an inhibitor of GA biosynthesis, and gibberellic acid (GA3) to monitor translational regulation of mRNAs globally. Gibberellin levels did not affect levels of carbohydrates in plants treated with PAC and/or GA3. However, the tricarboxylic acid cycle intermediates malate and fumarate, two alternative carbon storage molecules, accumulated upon PAC treatment. Moreover, an increase in nitrate and in the levels of the amino acids was observed in plants grown under a low GA regime. Only minor changes in amino acid levels were detected in plants treated with GA3 alone, or PAC plus GA3. Comparison of the molecular changes at the transcript and metabolite levels demonstrated that a low GA level mainly affects growth by uncoupling growth from carbon availability. These observations, together with the translatome changes, reveal an interaction between energy metabolism and GA-mediated control of growth to coordinate cell wall extension, secondary metabolism, and lipid metabolism. PMID:22291129

  5. Interactions between ethylene, gibberellins, and brassinosteroids in the development of rhizobial and mycorrhizal symbioses of pea.

    PubMed

    Foo, Eloise; McAdam, Erin L; Weller, James L; Reid, James B

    2016-04-01

    The regulation of arbuscular mycorrhizal development and nodulation involves complex interactions between the plant and its microbial symbionts. In this study, we use the recently identified ethylene-insensitive ein2 mutant in pea (Pisum sativum L.) to explore the role of ethylene in the development of these symbioses. We show that ethylene acts as a strong negative regulator of nodulation, confirming reports in other legumes. Minor changes in gibberellin1 and indole-3-acetic acid levels in ein2 roots appear insufficient to explain the differences in nodulation. Double mutants produced by crosses between ein2 and the severely gibberellin-deficient na and brassinosteroid-deficient lk mutants showed increased nodule numbers and reduced nodule spacing compared with the na and lk single mutants, but nodule numbers and spacing were typical of ein2 plants, suggesting that the reduced number of nodules innaandlkplants is largely due to the elevated ethylene levels previously reported in these mutants. We show that ethylene can also negatively regulate mycorrhizae development when ethylene levels are elevated above basal levels, consistent with a role for ethylene in reducing symbiotic development under stressful conditions. In contrast to the hormone interactions in nodulation, ein2 does not override the effect of lk or na on the development of arbuscular mycorrhizae, suggesting that brassinosteroids and gibberellins influence this process largely independently of ethylene.

  6. Antioxidant activity, total phenolic and total flavonoid contents of whole plant extracts Torilis leptophylla L

    PubMed Central

    2012-01-01

    Background The aim of this study was to screen various solvent extracts of whole plant of Torilis leptophylla to display potent antioxidant activity in vitro and in vivo, total phenolic and flavonoid contents in order to find possible sources for future novel antioxidants in food and pharmaceutical formulations. Material and methods A detailed study was performed on the antioxidant activity of the methanol extract of whole plant of Torilis leptophylla (TLM) and its derived fractions {n-hexane (TLH), chloroform (TLC) ethyl acetate (TLE) n-butanol (TLB) and residual aqueous fraction (TLA)} by in vitro chemical analyses and carbon tetrachloride (CCl4) induced hepatic injuries (lipid peroxidation and glutathione contents) in male Sprague-Dawley rat. The total yield, total phenolic (TPC) and total flavonoid contents (TFC) of all the fractions were also determined. TLM was also subjected to preliminary phytochemical screening test for various constituents. Results The total phenolic contents (TPC) (121.9±3.1 mg GAE/g extract) of TLM while total flavonoid contents (TFC) of TLE (60.9 ±2.2 mg RTE/g extract) were found significantly higher as compared to other solvent fractions. Phytochemical screening of TLM revealed the presence of alkaloids, anthraquinones, cardiac glycosides, coumarins, flavonoids, saponins, phlobatannins, tannins and terpenoids. The EC50 values based on the DPPH (41.0±1 μg/ml), ABTS (10.0±0.9 μg/ml) and phosphomolybdate (10.7±2 μg/ml) for TLB, hydroxyl radicals (8.0±1 μg/ml) for TLC, superoxide radicals (57.0±0.3 μg/ml) for TLM and hydrogen peroxide radicals (68.0±2 μg/ml) for TLE were generally lower showing potential antioxidant properties. A significant but marginal positive correlation was found between TPC and EC50 values for DPPH, hydroxyl, phosphomolybdate and ABTS, whereas another weak and positive correlation was determined between TFC and EC50 values for superoxide anion and hydroxyl radicals. Results of in vivo experiment

  7. Pharmacognostic Specification, Chlorogenic Acid Content, and In vitro Antioxidant Activities of Lonicera japonica Flowering Bud

    PubMed Central

    Chaowuttikul, Chayanon; Palanuvej, Chanida; Ruangrungsi, Nijsiri

    2017-01-01

    Background: Lonicera japonica Thunb. or Japanese Honeysuckle has been widely used in traditional medicine for antipyretic. Objective: To establish the pharmacognostic specification of L. japonica flowering bud in Thailand and to determine its chlorogenic acid content and in vitro antioxidant activities. Materials and Methods: Dried L. japonica flowering bud from 15 various herbal drugstores throughout Thailand were investigated for pharmacognostic specification. Their chlorogenic acid contents were quantitatively analyzed by thin layer chromatography (TLC) densitometry with winCATS software. The mobile phase for TLC development consisted of ethyl acetate: formic acid: acetic acid: water (10:1.1:1.1:2.6). Antioxidant activities were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric ion reducing antioxidant power assay, nitric oxide scavenging assay, and β-carotene bleaching assays. Results: Qualified L. japonica flowering bud in Thailand was presented that the contents of loss on drying, total ash, acid-insoluble ash, and water should not be >10.11%, 6.59%, 1.14%, and 10.82% by weight, respectively. The ethanol and water soluble extractive values should not be < 16.46% and 28.88% by weight, respectively. Chlorogenic acid content in L. japonica flowering bud was found to be 2.24 ± 0.50 g/100 g of crude drug. L. japonica flowering bud showed DPPH and nitric oxide scavenging activities as well as reducing power property. Conclusion: This pharmacognostic specification with special reference to the chlorogenic acid content can be used for quality control of L. japonica flowering bud in Thailand. The potential antioxidant of this crude drug was demonstrated in vitro. SUMMARY Pharmacognostic specification of Lonicera japonica flowering bud in Thailand has been establishedThe chlorogenic acid content has been quantified by thin layer chromatography-densitometryThe ethanolic extract of L. japonica flowering bud showed antioxidation potential

  8. Pharmacognostic Specification, Chlorogenic Acid Content, and In vitro Antioxidant Activities of Lonicera japonica Flowering Bud.

    PubMed

    Chaowuttikul, Chayanon; Palanuvej, Chanida; Ruangrungsi, Nijsiri

    2017-01-01

    Lonicera japonica Thunb. or Japanese Honeysuckle has been widely used in traditional medicine for antipyretic. To establish the pharmacognostic specification of L. japonica flowering bud in Thailand and to determine its chlorogenic acid content and in vitro antioxidant activities. Dried L. japonica flowering bud from 15 various herbal drugstores throughout Thailand were investigated for pharmacognostic specification. Their chlorogenic acid contents were quantitatively analyzed by thin layer chromatography (TLC) densitometry with winCATS software. The mobile phase for TLC development consisted of ethyl acetate: formic acid: acetic acid: water (10:1.1:1.1:2.6). Antioxidant activities were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric ion reducing antioxidant power assay, nitric oxide scavenging assay, and β-carotene bleaching assays. Qualified L. japonica flowering bud in Thailand was presented that the contents of loss on drying, total ash, acid-insoluble ash, and water should not be >10.11%, 6.59%, 1.14%, and 10.82% by weight, respectively. The ethanol and water soluble extractive values should not be < 16.46% and 28.88% by weight, respectively. Chlorogenic acid content in L. japonica flowering bud was found to be 2.24 ± 0.50 g/100 g of crude drug. L. japonica flowering bud showed DPPH and nitric oxide scavenging activities as well as reducing power property. This pharmacognostic specification with special reference to the chlorogenic acid content can be used for quality control of L. japonica flowering bud in Thailand. The potential antioxidant of this crude drug was demonstrated in vitro. Pharmacognostic specification of Lonicera japonica flowering bud in Thailand has been establishedThe chlorogenic acid content has been quantified by thin layer chromatography-densitometryThe ethanolic extract of L. japonica flowering bud showed antioxidation potential, especially on reducing power property. Abbreviations Used: TLC: Thin layer

  9. Cytotoxic, Antioxidant and Antimicrobial Activities and Phenolic Contents of Eleven Salvia Species from Iran

    PubMed Central

    Firuzi, Omidreza; Miri, Ramin; Asadollahi, Mojtaba; Eslami, Saba; Jassbi, Amir Reza

    2013-01-01

    The plants of the genus Salvia synthesize several types of secondary metabolites with antimicrobial, cytotoxic, and radical scavenging activities and are used in the folk medicine of different countries. Eleven Salvia species including S. aegyptiaca, S. aethiopis, S. atropatana, S. eremophila, S. hypoleuca, S. limbata, S. nemorosa, S. santolinifolia, S. sclarea, S. syriaca, and S. xanthocheila were collected from different localities in Iran and screened for their cytotoxic activity using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. The antioxidant potential and total phenol contents of the plant extracts were assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and Folin- Ciocalteu reagent respectively and finally antimicrobial activity of the above extracts were determined by using agar disc diffusion (ADD) and nutrient broth micro-dilution (NBMD) bioassays. Cytotoxic activity of methanol, 80% methanol and dichloromethane extracts of these plants were assessed on 3 human cancer cell lines. All of the extracts of S. eremophila and S. santolinifolia were active at IC50 values of 10.5-75.2 μg extract/mL, while the methanol and dichloromethane extracts of S. limbata, S. hypoleuca and S. aethiopis showed considerable cytotoxic activity against the tested cell lines. Among the tested plants for their antioxidant activity, S. nemorosa, S. atropatana, S. santolinifolia, and S. eremophila were the most active radical scavengers with higher total phenol contents while, S. limbata, S. xanthocheila and S. aegyptiaca were the weakest ones. The methanol extracts of S. santolinifolia, S. eremophila, S. sclarea and S. limbata inhibited the growth of all tested bacterial strains. PMID:24523760

  10. Pharmacognostic evaluation with reference to catechin content and antioxidant activities of pale catechu in Thailand

    PubMed Central

    Duangyod, Thidarat; Palanuvej, Chanida; Ruangrungsi, Nijsiri

    2015-01-01

    Pale catechu, a well-known crude drug, has been widely used for anti-diarrhea. Due to its medicinal usage, this study was performed to evaluate the pharmacognostic and antioxidant properties as well as catechins contents of pale catechu in Thailand. Twenty samples of pale catechu collected from traditional drug stores throughout Thailand were investigated. Antioxidant activities, total phenolic, nontannin phenolic, and total tannin contents were evaluated. (+)-catechin and (−)-epicatechin were quantitatively analyzed by high performance liquid chromatography. The results revealed that most of pale catechu samples were adulterated according to high ash values. Qualified pale catechu in Thailand were demonstrated for their average contents of total ash, acid insoluble ash, loss on drying, and moisture as 5.20 ± 0.19, 1.61 ± 0.17, 13.14 ± 0.10, and 13.20 ± 1.07 g/100 g of dry weight, respectively. The ethanol and water soluble extractive matters were 91.66 ± 5.16 and 44.59 ± 3.18 g/100 g of dry weight respectively. (+)-catechin in theses samples was 478.87 ± 2.77 μg/mg of crude drug, whereas (−)-epicatechin was found to be trace (activities were demonstrated compared to (+)-catechin hydrate. PMID:26317072

  11. Effect of methyl jasmonate on the anthocyanin content and antioxidant activity of blueberries during cold storage.

    PubMed

    Huang, Xiaojie; Li, Jing; Shang, Hongli; Meng, Xin

    2015-01-01

    The effects of postharvest methyl jasmonate (MeJA) fumigation on total soluble solids (TSS), titratable acidity (TA), ascorbic acid, total phenolic content (TPC), total monomeric anthocyanins (TMAs), individual anthocyanins and antioxidant activity of blueberries stored at 1 °C for 28 days were evaluated. Prior to storage, the blueberries were fumigated with 0.05 mmol L(-1) MeJA for 12 h. Control blueberries were subjected to the same conditions but were not exposed to MeJA. MeJA treatment had no adverse effect on TSS and TA and inhibited the decrease in ascorbic acid during storage. MeJA treatment induced an enhancement in TPC on day 21; TPC decreased thereafter. Similarly, a significant increase in TMAs and individual anthocyanins was observed 21 days after MeJA treatment. TPC, TMAs and individual anthocyanins increased in control fruits on day 7 and decreased thereafter. Moreover, MeJA treatment maintained higher levels of antioxidant activity during the entire storage period. These results suggest that cold storage enhances TPC, TMAs and individual anthocyanin content during short-term storage. However, postharvest application of MeJA to blueberries enhances TPC, TMAs and individual anthocyanin content during long-term storage. © 2014 Society of Chemical Industry.

  12. Acetylcholine content and viability of cholinergic neurons are influenced by the activity of protein histidine phosphatase.

    PubMed

    Eißing, Anna; Fischer, Daniel; Rauch, Ilka; Baumann, Anne; Schebb, Nils-Helge; Karst, Uwe; Rose, Karsten; Klumpp, Susanne; Krieglstein, Josef

    2012-03-21

    The first mammalian protein histidine phosphatase (PHP) was discovered in the late 90s of the last century. One of the known substrates of PHP is ATP-citrate lyase (ACL), which is responsible--amongst other functions--for providing acetyl-CoA for acetylcholine synthesis in neuronal tissues. It has been shown in previous studies that PHP downregulates the activity of ACL by dephosphorylation. According to this our present work focused on the influence of PHP activity on the acetylcholine level in cholinergic neurons. The amount of PHP in SN56 cholinergic neuroblastoma cells was increased after overexpression of PHP by using pIRES2-AcGFP1-PHP as a vector. We demonstrated that PHP overexpression reduced the acetylcholine level and induced cell death. The acetylcholine content of SN56 cells was measured by fast liquid chromatography-tandem mass spectrometry method. Overexpression of the inactive H53A-PHP mutant also induced cell damage, but in a significantly reduced manner. However, this overexpression of the inactive PHP mutant did not change the acetylcholine content of SN56 cells significantly. In contrast, PHP downregulation, performed by RNAi-technique, did not induce cell death, but significantly increased the acetylcholine content in SN56 cells. We could show for the first time that PHP downregulation increased the acetylcholine level in SN56 cells. This might be a potential therapeutic strategy for diseases involving cholinergic deficits like Alzheimer's disease.

  13. Acetylcholine content and viability of cholinergic neurons are influenced by the activity of protein histidine phosphatase

    PubMed Central

    2012-01-01

    Background The first mammalian protein histidine phosphatase (PHP) was discovered in the late 90s of the last century. One of the known substrates of PHP is ATP-citrate lyase (ACL), which is responsible - amongst other functions - for providing acetyl-CoA for acetylcholine synthesis in neuronal tissues. It has been shown in previous studies that PHP downregulates the activity of ACL by dephosphorylation. According to this our present work focused on the influence of PHP activity on the acetylcholine level in cholinergic neurons. Results The amount of PHP in SN56 cholinergic neuroblastoma cells was increased after overexpression of PHP by using pIRES2-AcGFP1-PHP as a vector. We demonstrated that PHP overexpression reduced the acetylcholine level and induced cell death. The acetylcholine content of SN56 cells was measured by fast liquid chromatography-tandem mass spectrometry method. Overexpression of the inactive H53A-PHP mutant also induced cell damage, but in a significantly reduced manner. However, this overexpression of the inactive PHP mutant did not change the acetylcholine content of SN56 cells significantly. In contrast, PHP downregulation, performed by RNAi-technique, did not induce cell death, but significantly increased the acetylcholine content in SN56 cells. Conclusions We could show for the first time that PHP downregulation increased the acetylcholine level in SN56 cells. This might be a potential therapeutic strategy for diseases involving cholinergic deficits like Alzheimer's disease. PMID:22436051

  14. Ethnobotanical study, antifungal activity, phytochemical screening and total phenolic content of Algerian Aristolochia longa.

    PubMed

    Benarba, Bachir; Meddah, Boumedienne

    2014-01-01

    Aristolochia longa (from the family Aristolochiaceae) is widely used in Algerian traditional medicine. Here, we document ethnomedicinal uses by local population of Mascara province (West Algeria) and we evaluate the antifungal activity, the phytochemical composition and total phenolic content of aqueous extract (decoction) of the roots of A. longa from Algeria. The ethnobotanical investigation was carried out in Mascara Province (West Algeria). Antifungal activity was assessed against Saccharomyces cerevisiae. Total phenolic content was measured using the Folin-Ciocalteu's reagent. Our results showed that A. longa is widely used to treat several ailments such as cancer (38%), skin infections (14%), and diabetes (11%). Crushed roots are commonly used (89%) mixed with honey, milk, water or other medicinal plants. A. longa aqueous extract induced growth inhibition of S. cerevisiae cells in a dose - and time - dependent manner. An effective suppression of S. cerevisiae (97.06% inhibition of proliferation) was obtained at the 500 µg/mL after 72 h. Results of the phytochemical screening revealed that A. longa aqueous extract contained various bioactive compounds, including polyphenols and flavonoids. Total phenolic content in A. longa aqueous extract was found to be 6.07 ± 0.12 mg (gallic acid equivalents)/g. A. longa may be considered as a promising source of new drugs for treating cancer and as a good antifungal agent.

  15. Ethnobotanical study, antifungal activity, phytochemical screening and total phenolic content of Algerian Aristolochia longa

    PubMed Central

    Benarba, Bachir; Meddah, Boumedienne

    2014-01-01

    Aim: Aristolochia longa (from the family Aristolochiaceae) is widely used in Algerian traditional medicine. Here, we document ethnomedicinal uses by local population of Mascara province (West Algeria) and we evaluate the antifungal activity, the phytochemical composition and total phenolic content of aqueous extract (decoction) of the roots of A. longa from Algeria. Materials and Methods: The ethnobotanical investigation was carried out in Mascara Province (West Algeria). Antifungal activity was assessed against Saccharomyces cerevisiae. Total phenolic content was measured using the Folin–Ciocalteu’s reagent. Results: Our results showed that A. longa is widely used to treat several ailments such as cancer (38%), skin infections (14%), and diabetes (11%). Crushed roots are commonly used (89%) mixed with honey, milk, water or other medicinal plants. A. longa aqueous extract induced growth inhibition of S. cerevisiae cells in a dose - and time - dependent manner. An effective suppression of S. cerevisiae (97.06% inhibition of proliferation) was obtained at the 500 µg/mL after 72 h. Results of the phytochemical screening revealed that A. longa aqueous extract contained various bioactive compounds, including polyphenols and flavonoids. Total phenolic content in A. longa aqueous extract was found to be 6.07 ± 0.12 mg (gallic acid equivalents)/g. Conclusion: A. longa may be considered as a promising source of new drugs for treating cancer and as a good antifungal agent. PMID:26401365

  16. Determination of Antiproliferative Activities of Volatile Contents and HPLC Profiles of Dicranum scoparium (Dicranaceae, Bryophyta).

    PubMed

    Abay, Gökhan; Altun, Muhammed; Koldaş, Serkan; Tüfekçi, Ali Rıza; Demirtas, Ibrahim

    2015-01-01

    The aim of this study was to examine the anticancer activities and phytochemical profiles of Dicranum scoparium against HeLa cell lines. The bio-guided fractionation studies of dichloromethane extract have high antiproliferative activities. Fractions 7, 9, 19, 20 are rich source of unsaturated fatty acids, and- in the case of Fr-19 may improve the antiproliferative activities as well as increase the unsaturated fatty acid content. The effect of proliferative activities in hexane extract can be attributed to the saturated fatty acid composition of D. scoparium. The Fr-9 exhibited strong antiproliferative activity at concentrations of 100 and 50 μg mL(-1) compared to 5-FU. The fractions of 7, 9, 19 and 20 from dichloromethane extracts exhibited antiproliferative activities at a concentration of 100 μg mL(-1). The HPLC-TOF/MS studies gave nine compounds from the most active fraction of dichloromethane at concentrations of 250 and 100 μg mL(-1). The lower activities were obtained from the fractions including steroid derivatives.

  17. Reconstruction of the isotope activity content of heterogeneous nuclear waste drums.

    PubMed

    Krings, Thomas; Mauerhofer, Eric

    2012-07-01

    Radioactive waste must be characterized in order to verify its conformance with national regulations for intermediate storage or its disposal. Segmented gamma scanning (SGS) is a most widely applied non-destructive analytical technique for the characterization of radioactive waste drums. The isotope specific activity content is generally calculated assuming a homogeneous matrix and activity distribution for each measured drum segment. However, real radioactive waste drums exhibit non-uniform isotope and density distributions most affecting the reliability and accuracy of activities reconstruction in SGS. The presence of internal shielding structures in the waste drum contributes generally to a strong underestimation of the activity and this in particular for radioactive sources emitting low energy gamma-rays independently of their spatial distribution. In this work we present an improved method to quantify the activity of spatially concentrated gamma-emitting isotopes (point sources or hot spots) in heterogeneous waste drums with internal shielding structures. The isotope activity is reconstructed by numerical simulations and fits of the angular dependent count rate distribution recorded during the drum rotation in SGS using an analytical expression derived from a geometric model. First results of the improved method and enhancements of this method are shown and are compared to each other as well as to the conventional method which assumes a homogeneous matrix and activity distribution. It is shown that the new model improves the accuracy and the reliability of the activity reconstruction in SGS and that the presented algorithm is suitable with respect to the framework requirement of industrial application.

  18. Reduction of adsorption capacity of coconut shell activated carbon for organic vapors due to moisture contents.

    PubMed

    Abiko, Hironobu; Furuse, Mitsuya; Takano, Tsuguo

    2010-01-01

    In occupational hygiene, activated carbon produced from coconut shell is a common adsorbent material for harmful substances including organic vapors due to its outstanding adsorption capacity and cost advantage. However, moisture adsorption of the carbon generally decreases the adsorption capacity for organic vapors. In a previous report, we prepared several coconut shell activated carbons which had been preconditioned by equilibration with moisture at different relative humidities and measured the breakthrough times for 6 kinds of organic vapor, in order to clarify the effect of preliminary moisture content in activated carbon on the adsorption capacity in detail. We found that the relative percent weight increase due to moisture adsorption of the carbon specimen had a quantitative effect, reducing the breakthrough time. In this report, we carried out further measurements of the effect of moisture content on the adsorption of 13 kinds of organic vapor, and investigated the relationship between moisture adsorption and the reduction of the breakthrough time of activated carbon specimens. We also applied the data to the Wood's breakthrough time estimation model which is an extension of the Wheeler-Jonas equation.

  19. Multiplexed assays by high-content imaging for assessment of GPCR activity.

    PubMed

    Ross, D A; Lee, S; Reiser, V; Xue, J; Alves, K; Vaidya, S; Kreamer, A; Mull, R; Hudak, E; Hare, T; Detmers, P A; Lingham, R; Ferrer, M; Strulovici, B; Santini, F

    2008-07-01

    G-protein-coupled receptors (GPCR) participate in many disease pathways and represent the largest family of therapeutic targets. Thus, great investments are made to discover drugs modulating GPCR-mediated events. Among functional assays for screening GPCRs, the Transfluor imaging assay is based on redistribution of cytosolic beta-arrestin to an activated GPCR and has become widely used in high-content screening. However, assessing Transfluor alone has limitations: relying on a single mechanistic step of beta-arrestin redistribution during GPCR activation, providing no information on the stimulated GPCR's intracellular fate, and using only a single fluorescent color (green fluorescent protein). Taking full advantage of high-content imaging to screen approximately 2000 compounds, the authors multiplexed the Transfluor assay with an immunofluorescence-based quantification of GPCR internalization. This approach identified and classified 377 compounds interfering with agonist-induced activation of the Transfluor assay, receptor internalization, or both. In addition, a subset of compounds was analyzed for their performance across imaging, cell-based calcium release (fluorometric imaging plate reader [FLIPR]), and biochemical receptor binding assays (scintillation proximity assay). This indicated that the imaging assays have even better predictive power for direct inhibition of receptor binding than the FLIPR assay. In conclusion, compounds inducing unique responses can suggest novel mechanisms of action and be used as tools to study GPCR activation and internalization.

  20. Changes of Cyanide Content and Linamarase Activity in Wounded Cassava Roots 1

    PubMed Central

    Kojima, Mineo; Iwatsuki, Norio; Data, Emma S.; Villegas, Cynthia Dolores V.; Uritani, Ikuzo

    1983-01-01

    When cassava (Manihot esculenta Crantz) root was cut into blocks and incubated under laboratory conditions, the blocks showed more widespread and more even symptoms of physiological deterioration than those under natural conditions. Thus, the tissue block system has potential for biochemical studies of natural deterioration of cassava root. The changes in cyanide content and linamarase (linamarin β-d-glucoside glucohydrolase; EC 3.2.1.21) activity in various tissues during physiological deterioration were investigated. Total cyanide content increased in all parts of block tissue after 3-day incubation. The degree of increase in cyanide was most pronounced in white parenchymal tissue, 2 to 3 millimeters thick, next to the cortex (A-part tissue), where no physiological symptoms appeared. On the other hand, linamarase activity was decreased in all parts of block tissue after a 3-day incubation. A time course analysis of A-part tissue indicated a clear reciprocal relationship between changes in total cyanide and linamarase activity; total cyanide increased, while linamarase activity decreased. Free cyanide constituted a very small portion of the total cyanide and did not change markedly. Images Fig. 2 PMID:16662957

  1. Tomato fruit ascorbic acid content is linked with monodehydroascorbate reductase activity and tolerance to chilling stress.

    PubMed

    Stevens, R; Page, D; Gouble, B; Garchery, C; Zamir, D; Causse, M

    2008-08-01

    Quantitative trait loci (QTL) mapping is a step towards the identification of factors regulating traits such as fruit ascorbic acid content. A previously identified QTL controlling variations in tomato fruit ascorbic acid has been fine mapped and reveals that the QTL has a polygenic and epistatic architecture. A monodehydroascorbate reductase (MDHAR) allele is a candidate for a proportion of the increase in fruit ascorbic acid content. The MDHAR enzyme is active in different stages of fruit ripening, shows increased activity in the introgression lines containing the wild-type (Solanum pennellii) allele, and responds to chilling injury in tomato along with the reduced/oxidized ascorbate ratio. Low temperature storage of different tomato introgression lines with all or part of the QTL for ascorbic acid and with or without the wild MDHAR allele shows that enzyme activity explains 84% of the variation in the reduced ascorbic acid levels of tomato fruit following storage at 4 degrees C, compared with 38% at harvest under non-stress conditions. A role is indicated for MDHAR in the maintenance of ascorbate levels in fruit under stress conditions. Furthermore, an increased fruit MDHAR activity and a lower oxidation level of the fruit ascorbate pool are correlated with decreased loss of firmness because of chilling injury.

  2. The Effect of Physical Activity on Science Competence and Attitude towards Science Content

    NASA Astrophysics Data System (ADS)

    Klinkenborg, Ann Maria

    This study examines the effect of physical activity on science instruction. To combat the implications of physical inactivity, schools need to be willing to consider all possible opportunities for students to engage in moderate-to-vigorous physical activity (MVPA). Integrating physical activity with traditional classroom content is one instructional method to consider. Researchers have typically focused on integration with English/language arts (ELA) and mathematics. The purpose of this study was to determine the effect of physical activity on science competence and attitude towards science. Fifty-three third grade children participated in this investigation; one group received science instruction with a physical activity intervention while the other group received traditional science instruction. Participants in both groups completed a modified version of What I Really Think of Science attitude scale (Pell & Jarvis, 2001) and a physical science test of competence prior to and following the intervention. Children were videotaped during science instruction and their movement coded to measure the proportion of time spent in MVPA. Results revealed that children in the intervention group demonstrated greater MVPA during the instructional period. A moderate to large effect size (partial eta squared = .091) was seen in the intervention group science competence post-test indicating greater understanding of force, motion, work, and simple machines concepts than that of the control group who were less physically active. There was no statistically significant attitude difference between the intervention and control groups post-test, (F(1,51) = .375, p = .543). These results provide evidence that integration can effectively present physical science content and have a positive impact on the number of minutes of health-enhancing physical activity in a school day.

  3. Definition of Small Gram Quantity Contents for Type B Radioactive Material Transportation Packages: Activity-Based Content Limitations

    SciTech Connect

    Sitaraman, S; Kim, S; Biswas, D; Hafner, R; Anderson, B

    2010-10-27

    Since the 1960's, the Department of Transportation Specification (DOT Spec) 6M packages have been used extensively for transportation of Type B quantities of radioactive materials between Department of Energy (DOE) facilities, laboratories, and productions sites. However, due to the advancement of packaging technology, the aging of the 6M packages, and variability in the quality of the packages, the DOT implemented a phased elimination of the 6M specification packages (and other DOT Spec packages) in favor of packages certified to meet federal performance requirements. DOT issued the final rule in the Federal Register on October 1, 2004 requiring that use of the DOT Specification 6M be discontinued as of October 1, 2008. A main driver for the change was the fact that the 6M specification packagings were not supported by a Safety Analysis Report for Packaging (SARP) that was compliant with Title 10 of the Code of Federal Regulations part 71 (10 CFR 71). Therefore, materials that would have historically been shipped in 6M packages are being identified as contents in Type B (and sometimes Type A fissile) package applications and addenda that are to be certified under the requirements of 10 CFR 71. The requirements in 10 CFR 71 include that the Safety Analysis Report for Packaging (SARP) must identify the maximum radioactivity of radioactive constituents and maximum quantities of fissile constituents (10 CFR 71.33(b)(1) and 10 CFR 71.33(b)(2)), and that the application (i.e., SARP submittal or SARP addendum) demonstrates that the external dose rate (due to the maximum radioactivity of radioactive constituents and maximum quantities of fissile constituents) on the surface of the packaging (i.e., package and contents) not exceed 200 mrem/hr (10 CFR 71.35(a), 10 CFR 71.47(a)). It has been proposed that a 'Small Gram Quantity' of radioactive material be defined, such that, when loaded in a transportation package, the dose rates at external points of an unshielded packaging

  4. Evaluating bacterial activity from cell-specific ribosomal RNA content measured with oligonucleotide probes

    SciTech Connect

    Kemp, P.F.; Lee, S.; LaRoche, J.

    1992-10-01

    We describe a procedure for measuring the cell-specific quantity of ribosomal RNA (rRNA) and DNA in order to evaluate the frequency distribution of activity among cells. The procedure is inherently quantitative, does not require sample incubation and potentially can be taxon-specific. Fluorescently-labelled oligonucleotide probes are hybridized to the complementary 16S rRNA sequences in preserved, intact cells. The resulting cell fluorescence is proportional to cellular rRNA content and can be measured with a microscope-mounted photometer system, by image analysis, or by flow cytometry. Similarly, DNA content is measured as fluorescence of cells stained with the DNA specific fluorochrome DAPI. These are either prepared as separate samples for purposes of enumeration and DNA measurements, or are dual-labelled cells which are also hybridized with oligonucleotide probes.

  5. Evaluating bacterial activity from cell-specific ribosomal RNA content measured with oligonucleotide probes

    SciTech Connect

    Kemp, P.F.; Lee, S.; LaRoche, J.

    1992-01-01

    We describe a procedure for measuring the cell-specific quantity of ribosomal RNA (rRNA) and DNA in order to evaluate the frequency distribution of activity among cells. The procedure is inherently quantitative, does not require sample incubation and potentially can be taxon-specific. Fluorescently-labelled oligonucleotide probes are hybridized to the complementary 16S rRNA sequences in preserved, intact cells. The resulting cell fluorescence is proportional to cellular rRNA content and can be measured with a microscope-mounted photometer system, by image analysis, or by flow cytometry. Similarly, DNA content is measured as fluorescence of cells stained with the DNA specific fluorochrome DAPI. These are either prepared as separate samples for purposes of enumeration and DNA measurements, or are dual-labelled cells which are also hybridized with oligonucleotide probes.

  6. Content of redox-active compounds (ie, antioxidants) in foods consumed in the United States.

    PubMed

    Halvorsen, Bente L; Carlsen, Monica H; Phillips, Katherine M; Bøhn, Siv K; Holte, Kari; Jacobs, David R; Blomhoff, Rune

    2006-07-01

    Supplements containing ascorbic acid, alpha-tocopherol, or beta-carotene do not protect against oxidative stress-related diseases in most randomized intervention trials. We suggest that other redox-active phytochemicals may be more effective and that a combination of different redox-active compounds (ie, antioxidants or reductants) may be needed for proper protection against oxidative damage. We aimed to generate a ranked food table with values for total content of redox-active compounds to test this alternative antioxidant hypothesis. An assay that measures the total concentration of redox-active compounds above a certain cutoff reduction potential was used to analyze 1113 food samples obtained from the US Department of Agriculture National Food and Nutrient Analysis Program. Large variations in the content of antioxidants were observed in different foods and food categories. The food groups spices and herbs, nuts and seeds, berries, and fruit and vegetables all contained foods with very high antioxidant contents. Most food categories also contained products almost devoid of antioxidants. Of the 50 food products highest in antioxidant concentrations, 13 were spices, 8 were in the fruit and vegetables category, 5 were berries, 5 were chocolate-based, 5 were breakfast cereals, and 4 were nuts or seeds. On the basis of typical serving sizes, blackberries, walnuts, strawberries, artichokes, cranberries, brewed coffee, raspberries, pecans, blueberries, ground cloves, grape juice, and unsweetened baking chocolate were at the top of the ranked list. This ranked antioxidant food table provides a useful tool for investigations into the possible health benefit of dietary antioxidants.

  7. Dietary soy isoflavones increased hepatic protein disulfide isomerase content and suppressed its enzymatic activity in rats.

    PubMed

    Xiao, Chao Wu; Donak, Kevin; Ly, Olivia; Wood, Carla; Cooke, Gerard; Curran, Ivan

    2014-06-01

    Protein disulfide isomerase (PDI) is a multifunctional protein and plays important roles in protein folding, triglyceride transfer, insulin degradation, and thyroid hormone transportation. This study examined the modulation of PDI expression by soy consumption using rat as a model. Sprague-Dawley male and female rats at 50 days (d) of age were fed diets containing either 20% casein or alcohol-washed soy protein isolate (SPI, containing 50 mg isoflavones (ISFs)/kg diet) or SPI plus ISF (250 mg/kg diet) and mated at age of 120 d. The offspring (F1) were fed the same diets as their parents. Addition of ISF to SPI diet markedly increased PDI protein content in the liver and testis of the adult rats compared with the casein or SPI diet. PDI mRNA abundance in the liver and protein content in the brain, thyroid, heart, and uterus were unchanged by the diets. Two-dimensional Western blot showed that the rats fed diets containing SPI had a diminished hepatic PDI protein with an isoelectric point (pI) of 6.12, a dephosphorylated form, compared with the rats fed diets containing either casein or SPI with supplemental ISF. Soy ISF added into SPI diet remarkably suppressed hepatic PDI activity of the rats compared with the casein diet. Moreover, soy ISF dose-dependently increased PDI and thyroid hormone receptor (TR) β protein content, whereas reduced TR DNA binding ability in human hepatocytes. Overall, this study shows that soy ISF increased hepatic PDI protein content, but addition of ISF into SPI diet inhibited its enzymatic activities and this effect may be mediated through a post-transcriptional mechanism.

  8. Action of Gibberellins on Growth and Metabolism of Arabidopsis Plants Associated with High Concentration of Carbon Dioxide1[W

    PubMed Central

    Ribeiro, Dimas M.; Araújo, Wagner L.; Fernie, Alisdair R.; Schippers, Jos H.M.; Mueller-Roeber, Bernd

    2012-01-01

    Although the positive effect of elevated CO2 concentration [CO2] on plant growth is well known, it remains unclear whether global climate change will positively or negatively affect crop yields. In particular, relatively little is known about the role of hormone pathways in controlling the growth responses to elevated [CO2]. Here, we studied the impact of elevated [CO2] on plant biomass and metabolism in Arabidopsis (Arabidopsis thaliana) in relation to the availability of gibberellins (GAs). Inhibition of growth by the GA biosynthesis inhibitor paclobutrazol (PAC) at ambient [CO2] (350 µmol CO2 mol−1) was reverted by elevated [CO2] (750 µmol CO2 mol−1). Thus, we investigated the metabolic adjustment and modulation of gene expression in response to changes in growth of plants imposed by varying the GA regime in ambient and elevated [CO2]. In the presence of PAC (low-GA regime), the activities of enzymes involved in photosynthesis and inorganic nitrogen assimilation were markedly increased at elevated [CO2], whereas the activities of enzymes of organic acid metabolism were decreased. Under ambient [CO2], nitrate, amino acids, and protein accumulated upon PAC treatment; however, this was not the case when plants were grown at elevated [CO2]. These results suggest that only under ambient [CO2] is GA required for the integration of carbohydrate and nitrogen metabolism underlying optimal biomass determination. Our results have implications concerning the action of the Green Revolution genes in future environmental conditions. PMID:23090585

  9. Action of gibberellins on growth and metabolism of Arabidopsis plants associated with high concentration of carbon dioxide.

    PubMed

    Ribeiro, Dimas M; Araújo, Wagner L; Fernie, Alisdair R; Schippers, Jos H M; Mueller-Roeber, Bernd

    2012-12-01

    Although the positive effect of elevated CO(2) concentration [CO(2)] on plant growth is well known, it remains unclear whether global climate change will positively or negatively affect crop yields. In particular, relatively little is known about the role of hormone pathways in controlling the growth responses to elevated [CO(2)]. Here, we studied the impact of elevated [CO(2)] on plant biomass and metabolism in Arabidopsis (Arabidopsis thaliana) in relation to the availability of gibberellins (GAs). Inhibition of growth by the GA biosynthesis inhibitor paclobutrazol (PAC) at ambient [CO(2)] (350 µmol CO(2) mol(-1)) was reverted by elevated [CO(2)] (750 µmol CO(2) mol(-1)). Thus, we investigated the metabolic adjustment and modulation of gene expression in response to changes in growth of plants imposed by varying the GA regime in ambient and elevated [CO(2)]. In the presence of PAC (low-GA regime), the activities of enzymes involved in photosynthesis and inorganic nitrogen assimilation were markedly increased at elevated [CO(2)], whereas the activities of enzymes of organic acid metabolism were decreased. Under ambient [CO(2)], nitrate, amino acids, and protein accumulated upon PAC treatment; however, this was not the case when plants were grown at elevated [CO(2)]. These results suggest that only under ambient [CO(2)] is GA required for the integration of carbohydrate and nitrogen metabolism underlying optimal biomass determination. Our results have implications concerning the action of the Green Revolution genes in future environmental conditions.

  10. Convergence of auxin and gibberellin signaling on the regulation of the GATA transcription factors GNC and GNL in Arabidopsis thaliana.

    PubMed

    Richter, René; Behringer, Carina; Zourelidou, Melina; Schwechheimer, Claus

    2013-08-06

    Plant growth is regulated by a complex network of signaling events. Points of convergence for the signaling cross-talk between the phytohormones auxin and gibberellin (GA), which partly control overlapping processes during plant development, are largely unknown. At the cellular level, auxin responses are controlled by members of the AUXIN RESPONSE FACTOR (ARF) family of transcription factors as well as AUXIN/INDOLE-3-ACETIC ACID INDUCIBLE (AUX/IAA) proteins that repress the activity of at least a subset of ARFs. Here, we show that the two paralogous GATA transcription factors GATA, NITRATE-INDUCIBLE, CARBON-METABOLISM INVOLVED (GNC) and GNC-LIKE (GNL)/CYTOKININ-RESPONSIVE GATA FACTOR1 (CGA1) are direct and critical transcription targets downstream from ARF2 in the control of greening, flowering time, and senescence. Mutants deficient in the synthesis or signaling of the phytohormone GA are also impaired in greening, flowering, and senescence, and interestingly, GNC and GNL were previously identified as important transcription targets of the GA signaling pathway. In line with a critical regulatory role for GNC and GNL downstream from both auxin and GA signaling, we show here that the constitutive activation of GA signaling is sufficient to suppress arf2 mutant phenotypes through repression of GNC and GNL. In addition, we show that GA promotes ARF2 protein abundance through a translation-dependent mechanism that could serve to override the autoinhibitory negative feedback regulation of ARF2 on its own transcription and thereby further promote GA signaling.

  11. Comparative study of antioxidant activities and total phenolic content of selected edible wild mushrooms.

    PubMed

    Yim, Hip Seng; Chye, Fook Yee; Lee, Mee Yee; Matanjun, Patricia; How, Siew Eng; Ho, Chun Wai

    2011-01-01

    The present study aims to assess the antioxidant activities (AOA) and total phenolic content (TPC) of water extracts of selected edible wild mushrooms: Pleurotus porrigens, Schizophyllum commune, Hygrocybe conica, and Lentinus ciliatus. The AOA were evaluated against DPPH radical and ABTS radical cation scavenging ability, ferric-reducing antioxidant power (FRAP) and beta-carotene-linoleate bleaching (beta-CB) assays, and the Folin-Ciocalteu method for TPC. BHA was used as reference. P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability (90.78 +/- 0.30%) and FRAP (6.37 +/- 0.22 mM FE/100g), while Sch. commune showed significantly higher (p < 0.05) ABTS*+ inhibition activity (94.96 +/- 0.70%) and beta-CB inhibition activity (94.18 +/- 0.17%), respectively. TPC was found in a descending order of P. poriggens > L. ciliatus = Pleurotus ostreatus (cultivated) > H. conica = Sch. commune. Positive correlation was observed between the AOA and TPC. When compared to BHA (2 mM), P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability and reducing power, while Sch. commune showed comparable DPPH* scavenging ability and ABTS*+ inhibition activity. All the mushrooms have better ABTS*+ inhibition activity than BHA (1 mM). The beta-CB inhibition activity of BHA was significantly higher than those of edible wild mushrooms. The water extracts of edible wild mushrooms showed potent antioxidant activities compared to BHA to a certain extent.

  12. Apolipoprotein A-I lysine modification: effects on helical content, lipid binding and cholesterol acceptor activity.

    PubMed

    Brubaker, Gregory; Peng, Dao-Quan; Somerlot, Benjamin; Abdollahian, Davood J; Smith, Jonathan D

    2006-01-01

    We examined the role of the positively charged lysine residues in apoAI by chemical modification. Lysine modification by reductive methylation did not alter apoAI's net charge, secondary or tertiary structure as observed by circular dichroism and trytophan fluorescence, respectively, or have much impact on lipid binding or ABCA1-dependent cholesterol acceptor activity. Acetylation of lysine residues lowered the isoelectric point of apoAI, altered its secondary and tertiary structure, and led to a 40% decrease in cholesterol acceptor activity, while maintaining 93% of its lipid binding activity. Exhaustive lysine acetoacetylation lowered apoAI's isoelectric point, profoundly disrupted its secondary and tertiary structure, and led to 90% and 82% reductions in cholesterol acceptor and lipid binding activities, respectively. The dose-dependent acetoacetylation of an increasing proportion of apoAI lysine residues demonstrated that cholesterol acceptor activity was more sensitive to this modification than lipid binding activity, suggesting that apoAI lysine positive charges play an important role in ABCA1 mediated lipid efflux beyond the role needed to maintain alpha-helical content and lipid binding activity.

  13. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

    PubMed

    Chen, Xueqing; Pei, Yuansheng

    2016-10-01

    Sodium pentaborate pentahydrate (SPP) is a rare mineral. In this study, SPP was synthesized from boric acid and borax through low-temperature crystallization, and its effects on the growth of the alga, Chlorella vulgaris (C. vulgaris) were assessed. The newly synthesized SPP was characterized by chemical analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential thermal analysis. The changes in C. vulgaris growth, chlorophyll content, and enzyme activities upon exposure to SPP for 168h were evaluated. Results showed that SPP treatment was detrimental to C. vulgaris growth during the first 24-120h of exposure. The harmful effects, however, diminished over time (168h), even at an effective medium concentration of 226.37mg BL(-1) (the concentration of boron applied per liter of culture medium). A similar trend was observed for chlorophyll content (chlorophyll a and b) and indicated that the photosynthesis of C. vulgaris was not affected and that high levels of SPP may even promote chlorophyll synthesis. Superoxide dismutase and catalase activities of C. vulgaris increased during 24-120h exposure to SPP, but these activities gradually decreased as culture time progressed. In other words, the initial detrimental effects of synthetic SPP on C. vulgaris were temporary and reversible. This research provides a scientific basis for applications of SPP in the environment.

  14. [The content of phenolic compounds and antioxidant activity ready to eat desserts for infants].

    PubMed

    Filipiak-Florkiewicz, Agnieszka; Dereń, Katarzyna

    2011-01-01

    The aim of this study was to determine the content of phenolic compounds and antioxidant activity in ready-to-eat desserts for babies. The experimental material consisted of six kinds of fruit desserts taken from the market in 2008, in which the content of dry matter phenolic compounds and antioxidant activity levels on the basis of free radical quenching ability ABTS were determined. The largest share of dry matter was found in apricot mousse with apples and bananas (16.9%). The largest amounts of phenolic compounds were found in the cream with apple and wild rose (186.3 mg/100 g) and apple with forest fruits (170.7 mg/100 g). The highest antioxidant activity among the desserts was determined in cream with apple and wild rose (14.2 micromol Trolox/g) and apple mousse with peaches (12.8 micromol Trolox/g). The antioxidant capacity of the remaining examined purée was slightly lower and ranged from 11.4-11.7 micromol Trolox/g.

  15. Seasonal variability of Chelidonium majus L. secondary metabolites content and antioxidant activity

    PubMed Central

    Jakovljevic, Z. Dragana; Stankovic, S. Milan; Topuzovic, D. Marina

    2013-01-01

    The aim of this study is to investigate the total phenolic content, concentration of flavonoids and antioxidant activity in extracts of the plant Chelidonium majus L. during different phenological stages (stage of rosette, the initial flowering stage, the stage of fully formed flowers and stage of fruits formation). Five different extracts of the whole plant, for each phase, were obtained by extraction with water, methanol, acetone, ethyl acetate and petroleum ether. The concentration of total phenolic content was determined using the Folin-Ciocalteu´s reagent and obtained values were the highest in the rosette stage (60.96 mg GA/g). The concentration of flavonoids was the highest in the initial stage of flowering (291.58 mg RU/g). The antioxidant activity was determined in vitro using DPPH reagent. The highest antioxidant activity was expressed in the rosette stage (50.72 mg/ml). Based on the obtained results it can be concluded that the concentrations of secondary metabolites in Ch. majus depend on the phenological stage of the plant. PMID:27047313

  16. Seasonal variability of Chelidonium majus L. secondary metabolites content and antioxidant activity.

    PubMed

    Jakovljevic, Z Dragana; Stankovic, S Milan; Topuzovic, D Marina

    2013-01-01

    The aim of this study is to investigate the total phenolic content, concentration of flavonoids and antioxidant activity in extracts of the plant Chelidonium majus L. during different phenological stages (stage of rosette, the initial flowering stage, the stage of fully formed flowers and stage of fruits formation). Five different extracts of the whole plant, for each phase, were obtained by extraction with water, methanol, acetone, ethyl acetate and petroleum ether. The concentration of total phenolic content was determined using the Folin-Ciocalteu´s reagent and obtained values were the highest in the rosette stage (60.96 mg GA/g). The concentration of flavonoids was the highest in the initial stage of flowering (291.58 mg RU/g). The antioxidant activity was determined in vitro using DPPH reagent. The highest antioxidant activity was expressed in the rosette stage (50.72 mg/ml). Based on the obtained results it can be concluded that the concentrations of secondary metabolites in Ch. majus depend on the phenological stage of the plant.

  17. Determination of phytochemicals, antioxidant activity and total phenolic content in Andrographis paniculata using chromatographic methods.

    PubMed

    Kurzawa, Marzanna; Filipiak-Szok, Anna; Kłodzińska, Ewa; Szłyk, Edward

    2015-07-15

    Antioxidant activity, total phenolics content and selected phytochemicals (alkaloids and andrographolides) were determined in Andrographis paniculata and in dietary supplements containing this plant. Antioxidant activity was measured by FRAP, CUPRAC and DPPH procedures and ranged from 503.36 to 6164.09μmol TE/100g d.m. depending on methods, part of plant and kind of dietary supplement. The total phenolics (175.13-1723.79mg GAE/100g) and andrographolides content (19.44-85.13mg/g) in the studied samples were correlated with antioxidant activities determined by CUPRAC, FRAP and DPPH (r>0.95, p<0.05 level). Purine alkaloids: caffeine, theobromine, theophylline and indole alkaloids: harmine, harmane, harmol, yohimbine, brucine and strychnine were detected in the studied samples by different chromatographic techniques (HPLC-DAD, LC-MS/MS, GC-MS). The total alkaloids content in APs-roots and APs-leaves varies from 50.71±0.36mg/g d.m. to 78.71±0.48mg/g d.m., respectively, whereas for dietary supplements (Pn and DK) TAC was found between 19.52±0.15mg/g and 22.18±0.15mg/g d.m.. The highest concentration of andrographolides was found in A. paniculata leaves, whereas the lowest in dietary supplement Pn. Moreover principal component analysis, cluster analysis and one-way ANOVA follow by Duncan's tests were also performed.

  18. Transcriptional regulatory programs underlying barley germination and regulatory functions of Gibberellin and abscisic acid

    PubMed Central

    2011-01-01

    Background Seed germination is a complex multi-stage developmental process, and mainly accomplished through concerted activities of many gene products and biological pathways that are often subjected to strict developmental regulation. Gibberellins (GA) and abscisic acid (ABA) are two key phytohormones regulating seed germination and seedling growth. However, transcriptional regulatory networks underlying seed germination and its associated biological pathways are largely unknown. Results The studies examined transcriptomes of barley representing six distinct and well characterized germination stages and revealed that the transcriptional regulatory program underlying barley germination was composed of early, late, and post-germination phases. Each phase was accompanied with transcriptional up-regulation of distinct biological pathways. Cell wall synthesis and regulatory components including transcription factors, signaling and post-translational modification components were specifically and transiently up-regulated in early germination phase while histone families and many metabolic pathways were up-regulated in late germination phase. Photosynthesis and seed reserve mobilization pathways were up-regulated in post-germination phase. However, stress related pathways and seed storage proteins were suppressed through the entire course of germination. A set of genes were transiently up-regulated within three hours of imbibition, and might play roles in initiating biological pathways involved in seed germination. However, highly abundant transcripts in dry barley and Arabidopsis seeds were significantly conserved. Comparison with transcriptomes of barley aleurone in response to GA and ABA identified three sets of germination responsive genes that were regulated coordinately by GA, antagonistically by ABA, and coordinately by GA but antagonistically by ABA. Major CHO metabolism, cell wall degradation and protein degradation pathways were up-regulated by both GA and seed

  19. Gibberellin A[sub 1] is required for stem elongation in spinach

    SciTech Connect

    Zeevaart, J.A.D.; Gage, D.A.; Talon, M. )

    1993-08-01

    The effects of the growth retardants 2'-isopropyl-4'-(trimethylammonium chloride)-5'-methylphenyl piperidine-1-carboxylate (AMO-1618) and calcium 3,5-dioxo-4-propionylcyclohexanecarboxylate (BX-112) on stem elongation were investigated in the rosette plant spinach (Spinacia oleracea L.) under long-day (LD) conditions. Stem growth induced by a LD treatment was prevented by both retardants. The inhibition caused by AMO-1618 was reversed by gibberellin A[sub 1] (GA[sub 1]) and GA[sub 20], whereas the effects of BX-112 were reversed by GA[sub 1] only. Six GAs (GA[sub 53], GA[sub 44], GA[sub 19], GA[sub 20], GA[sub 1], and GA[sub 8]) were quantified by gas chromatography-selected ion monitoring using internal standards. Plants treated with BX-112 had reduced levels of GA[sub 1], and GA[sub 8] and accumulated GA[sub 53], GA[sub 44], GA[sub 19], and GA[sub 20]. The relative levels of four additional GAs (3-epi-GA[sub 1], GA[sub 29], GA[sub 60], and GA[sub 81]) were compared by ion intensities only. Relative to GA[sub 81], the level of GA[sub 29] was decreased by BX-112, whereas the levels of GA[sub 6] and 3-epi-GA[sub 1] were increased. Transfer of spinach from short-day conditions to LD conditions caused an increase in all identified GAs of the early 13-hydroxylation pathway with GA[sub 20], GA[sub 1], and GA[sub 8] showing the largest increases. These findings support the position that, of the GA[sub s] belonging to the early 13-hydroxylation pathway, GA[sub 1] is the primary GA active per se for stem elongation in spinach. The increase in endogenous GA[sub 1] in plants in LD conditions is most likely the primary factor for stem elongation. 23 refs., 7 figs., 3 tabs.

  20. Selenium contents in tobacco and main stream cigarette smoke determined using neutron activation analysis

    SciTech Connect

    Sorak-Pokrajac, M.; Dermelj, M.; Slejkovec, Z.

    1994-01-01

    In the domain of the essential trace elements, the role of selenium is extremely important. As one of the volatile elements it can be partly absorbed through the pulmonary system during smoking and transported to different organs of the body. Thus a knowledge of its concentration levels in various sorts of tobacco and in the smoke of commercial cigarettes, as well as in the same type of cigarettes from plants treated with selenium, is of interest for various research fields. The purpose of this contribution is to present reliable quantitative data on selenium contents in tobacco, soil, and main stream cigarette smoke, obtained by destructive neutron activation analysis.

  1. Effect of sulphur dioxide exposure on chlorophyll content and nitrogenase activity of Vicia faba L. plants

    SciTech Connect

    Agrawal, S.B.; Agrawal, M. )

    1991-11-01

    The annual average concentrations of SO{sub 2} around Obra thermal power plant and nonpolluted sites in India were reported as 0.06, and 0.007 ppm, respectively. However, daily average concentrations in areas close to the emission source may be as large as 0.34 ppm. Therefore, in the present investigation an attempt has been made to determine the potential effects of such episodic and exceptionally high intermittent concentrations of SO{sub 2} on total chlorophyll content and nitrogenase activity of Vicia faba (broad bean) plants.

  2. Sugars, ascorbic acid, total phenolic content and total antioxidant activity in passion fruit (Passiflora) cultivars.

    PubMed

    Devi Ramaiya, Shiamala; Bujang, Japar Sidik; Zakaria, Muta Harah; King, Wong Sing; Shaffiq Sahrir, Muhd Arif

    2013-03-30

    The levels of sugars, ascorbic acid, total phenolic content (TPC) and total antioxidant activity (TAA) were determined in fruit juices from seven passion fruit (Passiflora spp.) cultivars: P. edulis cultivars Purple, Frederick, Yellow, Pink, P. edulis f. flavicarpa, P. maliformis and P. quadrangularis (we also tested this cultivar's mesocarp). Purple and Yellow P. edulis had significantly higher total sugar, 142.85 ± 0.17 g kg⁻¹ and 139.69 ± 0.12 g kg⁻¹, respectively, than other cultivars. Glucose and fructose content were higher in juice from vine-ripened fruits of Purple, Frederick and Yellow P. edulis, P. quadrangularis and P. maliformis. Sucrose content was significantly higher in juice of non-vine-ripened fruits of P. edulis (Pink) and P. edulis f. flavicarpa. Ascorbic acid, TPC and TAA were significantly higher in vine-ripened Purple and Yellow P. edulis; ranges were 0.22-0.33 g kg⁻¹, 342.80-382.00 mg gallic acid equivalent L⁻¹ and 409.13-586.70 µmol Trolox L⁻¹, respectively. Based on principal component analysis (PCA) and cluster analysis, the main variables - °Brix, total sugar, glucose, fructose, ascorbic acid, TPC and TAA - formed the characteristics for the group comprising Purple and Yellow P. edulis. Glucose, fructose, sucrose, ascorbic acid, TAA and TPC were quantified in passion fruit juices. Variation of the above variables in juices of Passiflora depends on the cultivar and ripeness. © 2012 Society of Chemical Industry.

  3. [Amelioration effect of sand-fixing Hedysarum fruticosum plantations on soil nutrient contents and biological activities].

    PubMed

    Cao, Cheng-You; Jiang, De-Ming; Zhu, Li-Hui; Teng, Xiao-Hui; Fu, Yao; Cui, Zhen-Bo; Gao, Fei-Fei; Gao, En-Liang

    2007-08-01

    With adjacent semi-moving dune as the control, this paper studied the effects of 5-, 10- and 22-year old Hedysarum fruticosum plantations on the nutrient status, microbial biomass, and enzyme activities at the soil depths 0-10, 10-20 and 20-30 cm. The results showed that with the establishment of H. fruticosum plantation on moving dune, soil C, N, P and K contents and biological activities increased obviously with the increasing age of the plantation, and the increment was much higher at 0-10 cm than at 10-20 and 20-30 cm. At 0-30 cm, soil C/N increased from 7.3 to 8.5, and microbial biomass C, N and P as well as the activities of urease, protease, saccharase, phosphomonoesterase, dehydrogenase, polyphenol oxidase and nitrate reductase all increased. Among the test enzyme activities, saccharase activity had the most significant increase, with its value at 0-10 cm being 49.7-284.5 times of the control. There were significant positive correlations between soil microbial biomass C, N and P and organic C, total N and total P, respectively, and between soil microbial biomass and enzyme activities.

  4. The phytochemical content and antimicrobial activities of Malaysian Calophyllum canum (stem bark).

    PubMed

    Alkhamaiseh, Suhaib Ibrahim; Taher, Muhammad; Ahmad, Farediah; Qaralleh, Haitham; Althunibat, Osama Yousef; Susanti, Deny; Ichwan, Solachuddin-Jauhari Arief

    2012-07-01

    Recently there was huge increase in using of 'herbal products'. These can be defined as plants, parts of plants or extracts from plants that are used for curing disease. However, Calophyllum species is a tropical plant and it has been used in traditional medicine, the limitation in safety and effectiveness information could lead to serious health problems. Providing information for communities by evaluating the phytochemical contents, antioxidant, antimicrobial and cytotoxic activities will improve the therapeutic values. Three main Calophyllum canum fractions (none - high polar) were tested to find out the phenolic, flavonoid, flavonol content, DPPH radical scavenging, reducing power and chelating iron ions. Also were tested against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Psedomonas aeruginosa, Candida albicans, and Cryptococcus neoformans. In addition, cytotoxic activity was assayed against lung cancer A549 cell line. The methanol fraction showed no bioactivity but achieved the highest amount of phenolic, flavonol and flavonoid contents, also it showed a significant result as antioxidant, reducing power and chelating agent. The n-hexane fraction achieved the minimum inhibitory concentration (MIC) value 12.5 μg. mL(-1) against B. cereus while the MIC value for DCM fraction was 25 μg. mL(-1). The DCM fraction was more active against S. aureus where the result was 50 μg. mL(-1) while the n-hexane fraction was 100 μg. mL(-1). The three main fractions have shown no activity against gram negative bacterial and fungal. The n-hexane and DCM fractions have shown cytotoxicity against lung cancer cell line; the 50% inhibition concentration (IC(50)) was 22 ± 2.64 and 32 ± 3.78 μg. mL(-1) respectively. The results were statistically significant (P < 0.05). Among the results, C. canum fractions proved to be effective against gram positive bacterial and anti-proliferation activity. Also it showed antioxidant activity as well. The results provided

  5. Health Behavior Theory in Physical Activity Game Apps: A Content Analysis.

    PubMed

    Payne, Hannah E; Moxley, Victor Ba; MacDonald, Elizabeth

    2015-07-13

    Physical activity games developed for a mobile phone platform are becoming increasingly popular, yet little is known about their content or inclusion of health behavior theory (HBT). The objective of our study was to quantify elements of HBT in physical activity games developed for mobile phones and to assess the relationship between theoretical constructs and various app features. We conducted an analysis of exercise and physical activity game apps in the Apple App Store in the fall of 2014. A total of 52 apps were identified and rated for inclusion of health behavior theoretical constructs using an established theory-based rubric. Each app was coded for 100 theoretical items, containing 5 questions for 20 different constructs. Possible total theory scores ranged from 0 to 100. Descriptive statistics and Spearman correlations were used to describe the HBT score and association with selected app features, respectively. The average HBT score in the sample was 14.98 out of 100. One outlier, SuperBetter, scored higher than the other apps with a score of 76. Goal setting, self-monitoring, and self-reward were the most-reported constructs found in the sample. There was no association between either app price and theory score (P=.5074), or number of gamification elements and theory score (P=.5010). However, Superbetter, with the highest HBT score, was also the most expensive app. There are few content analyses of serious games for health, but a comparison between these findings and previous content analyses of non-game health apps indicates that physical activity mobile phone games demonstrate higher levels of behavior theory. The most common theoretical constructs found in this sample are known to be efficacious elements in physical activity interventions. It is unclear, however, whether app designers consciously design physical activity mobile phone games with specific constructs in mind; it may be that games lend themselves well to inclusion of theory and any

  6. Evaluation of antibacterial and anthelmintic activities with total phenolic contents of Piper betel leaves

    PubMed Central

    Akter, Kazi Nahid; Karmakar, Palash; Das, Abhijit; Anonna, Shamima Nasrin; Shoma, Sharmin Akter; Sattar, Mohammad Mafruhi

    2014-01-01

    Objective: The study was conducted to investigate the antibacterial and anthelmintic activities and to determine total phenolic contents of methanolic extract of Piper betel leaves. Materials and Methods: The extract was subjected to assay for antibacterial activity using both gram positive and gram negative bacterial strains through disc diffusion method; anthelmintic activity with the determination of paralysis and death time using earthworm (Pheritima posthuma) at five different concentrations and the determination of total phenolic contents using the Folin-ciocalteau method. Results: The extract showed significant (p<0.01) zone of inhibitions against gram positive Staphylococcus aureus [(6.77±0.25) mm] and Gram negative Escherichia coli [(8.53±0.25) mm], Salmonella typhi [(5.20±0.26) mm], Shigella dysenteriae [(11.20±0.26) mm] compared to positive control Azithromycin (ranging from 20.10±0.17 to 25.20±0.35 mm) while no zone inhibitory activity was found for both the extract and the standard drug against Gram positive Bacillus cereus. The extract also showed potent anthelmintic activity requiring less time for paralysis and death compared to the standard drug albendazole (10 mg/ml). At concentrations 10, 20, 40, 60 and 80 mg/ml, leaves extract showed paralysis at mean time of 9.83±0.60, 8.50±0.29, 6.60±0.17, 6.20±0.44 and 4.16±0.60; death at 11.33±0.88