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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

EXPLORING THE MOLECULAR MECHANISM OF ROOT-MEDIATED RESPONSES TO <i>RALSTONIA</i>

Katherine Rivera-Zuluaga (17552421) 06 December 2023 (has links)
<p dir="ltr">Bacterial Wilt, caused by <i>Ralstonia solanacearum</i>, is among the most devastating plant diseases in the world. This pathogen causes significant loss in crops such as tobacco, potato, and tomato. <i>R. solanacearum</i> root infection and xylem colonization determine disease outcome. To date, little is known about the defense mechanism mediated by roots to prevent <i>R. solanacearum</i> vascular colonization during the initial infection stages. Plant early responses are important since they may impact disease outcomes<i>.</i><i> </i>Here, we report the formation of root hairs and primary root growth inhibition in tomato seedlings as <i>Ralstonia</i>-induced phenotypes that depend on tomato genotype and <i>Ralstonia</i> species. The <i>Ralstonia</i>-induced root phenotypes are independent of a functional type III secretion system and exopolysaccharide production (EPS). We also found that <i>R. solanacearum</i><i> </i>K60 infection increased auxin levels throughout the root meristem in wilt-susceptible tomato roots. Our data suggest proper auxin signaling and transport are important for susceptibility to <i>R. solanacearum</i> K60. Blocking auxin transport pharmacologically or genetically led to fewer wilting symptoms, suggesting that auxin is important during early infection stages and disease outcomes in tomato. We previously found that a tomato mutant defective in auxin transport and signaling, known as <i>diageotropica</i> (<i>dgt</i>), has enhanced resistance to <i>R. solanacearum</i> K60. We characterized the resistant response in the <i>dgt</i> mutant, and we found that the resistant response in the <i>dgt</i> mutant may be due to increased lignin content preventing pathogen vasculature colonization. <i>DGT</i> encodes a cyclophilin protein that regulates auxin transport and signaling. Mutations in the cyclophilin DGT promote resistance to <i>R. solanacearum</i> K60. DGT has been reported to regulate auxin transport and signaling. However, the molecular mechanism regarding how DGT mediates these processes is still unknown. We used Yeast Two-Hybrid to identify candidate protein interactors, and we found that SlbZIP1/SlbZIP29, Sl14-3-3, and SlMYB110 may interact with DGT to regulate both development and defense responses. Understanding the role of DGT, auxin, and lignin in defense responses to <i>R. solanacearum</i> K60 in tomato is necessary for Solanaceae crop improvement.</p>
172

Ecological and Chemical Aspects of White Oak Decline and Sudden Oak Death, Two Syndromes Associated With <i>Phytophthora</i> spp

Nagle, Annemarie Margaret January 2009 (has links)
No description available.
173

Effects of methyl jasmonate on chemical defenses of conifer seedlings in relation to feeding by Hylobius abietis

Lundborg, Lina January 2016 (has links)
The chemical elicitor methyl jasmonate (MeJA) could replace insecticides in Europe and Asia for protection of young conifers against the pine weevil (Hylobius abietis). This thesis mainly focuses on the effects of MeJA treatment on chemical defenses of conifers from seedling batches with documented field resistance. Tissues of three pine species and one spruce species, with various treatments, were here extracted in hexane, whereafter volatile contents of tissues were separated and analyzed by 2D GC-MS. Induced responses of seedlings of Maritime pine (Pinus pinaster) and Monterey pine (Pinus radiata) to the folivore pine processionary (Thaumetopoea pityocampa), and the phloem-feeder H. abietis, have been studied. Amounts of mono- and sesqui-terpenes (and also non-volatile resin) in conifer tissues (needles and phloem) were less induced by T. pityocampa than by H. abietis. The MeJA-treated seedlings of Scots pine (Pinus sylvestris) changed their composition of phloem monoterpenes (induction of (-)-β-pinene), and were better protected in field than the seedlings of Norway spruce (Picea abies), which increased their total amounts of monoterpenes. Orientation bioassays with H. abietis showed deterrent effects of (-)-β-pinene, (+)-3-carene, (-)-bornyl acetate and 1,8-cineole. Conversely, (-)-α-pinene (induced in P. abies but not in P. sylvestris) was non-deterrent. MeJA-treated seedlings fed on by H. abietis contained higher amounts of the H. abietis antifeedant 2-phenylethanol, in tissues and emissions. Phloem of control seedlings instead induced the (+)-α-pinene, which is one of the enantiomers of the H. abietis attractant α-pinene. In response to MeJA treatment, the relative amounts of the (+)-α-pinene increased in the phloem of  P. radiata, while it decreased in P. pinaster phloem. The preference of H. abietis in the field for P. radiata before P. pinaster may be explained by these changes in enantiomers of the H. abietis attractant α-pinene. / Barrträd är viktiga för skogsindustrin. I Sverige består 57% av ytan av produktiv skogsmark, och av dessa träd utgörs 80% av gran och tall. Som försvar mot insekter och sjukdomar, producerar barrträden kådämnen. För unga barrträd i Europa och Asien är snytbaggen (Hylobius abietis) en allvarlig skadegörare, som orsakar skogsnäringen stora kostnader. För att skydda små gran- och tallplantor före utplanteringen, skulle växthormonet metyljasmonat (MeJA) kunna användas. I denna avhandling har effekter av MeJA-behandling och insektsangrepp undersökts på de två viktigaste barrträden i Sverige, tall och gran (Pinus sylvestris och Picea abies) och på två arter i medelhavsområdet (Pinus radiata och Pinus pinaster). De kemiska försvarsämnena i barrträd har analyserats för att utvärdera effekterna av MeJA-behandling. Vävnader från barrträd med olika behandling har extraherats i organiska lösningsmedel och dofterna från plantorna har insamlats genom fastfas-mikroextraktion. De flyktiga ämnena har separerats och identifierats med hjälp av gaskromatografi och masspektrometri (GC-MS). Dessutom har optiskt aktiva doftämnen separerats med hjälp av en tvådimensionell GC-MS. Plantornas olika försvarsreaktioner har studerats vid angrepp av snytbaggen, som är en floemätare, och av tallfjärilslarv (Thaumetopoea pityocampa), som huvudsakligen äter barr. De lättflyktiga ämnena (mono- och seskviterpener) och de icke-flyktiga ämnena (kådsyror) ökade mer i stam och barr från angrepp av H. abietis än av T. pityocampa. Sammansättning av monoterpener ändrades i de MeJA-behandlade tallplantorna i Sverige, specifikt ökade (-)-β-pinene i stamfloemet. Tallplantorna var bättre skyddade i fält än granplantorna, där den totala mängden monoterpener ökade. (-)-β-Pinene, (+)-3-carene, (-)-bornyl acetate och 1,8-cineole visade sig ha en negativ effekt på snytbaggens orientering mot talldoft i orienteringstester. En av monoterpenerna, (-)-α-pinene, som av MeJA-behandlingen inducerats i granen, men inte i tallen, hade ingen negativ effekt på snytbaggen. MeJA-behandlade tallplantor som angripits av snytbaggen, innehöll större mängder av snytbagge-äthämmaren 2-fenyletanol, både i vävnader och i emissioner. Stam från kontrollplantor inducerade istället (+)-α-pinene, vilken är en av de optiska isomererna av snytbagge-attrahenten α-pinene. För de spanska arterna, som svar på MeJA-behandling, ökade de lättflyktigaste terpenerna i barren hos P. radiata men inte hos P. pinaster, vilken redan innehöll en hög terpenhalt. De relativa mängderna av (+)-α-pinene ökade också i stammen hos P. radiata, medan de minskade i P. pinaster. I fält väljer snytbaggen att gå till P. radiata- framför P. pinaster-plantor, vilket kan vara kopplat till de skillnader i α-pinene-isomerer, vilka här har observerats. / <p>QC 20160304</p>
174

Antioksidantna svojstva lekovitog bilja u hrani / Antioxidant Properties of Medicinal Plants in Food

Mišan Aleksandra 11 December 2009 (has links)
<p>U ovom radu je izvr&scaron;eno kvantitativno&nbsp;određivanje i identifikacija biljnih fenola i&nbsp;<br />flavonoida etanolih ekstrakata ploda per&scaron;una&nbsp;(<em>Petroselini fructus</em>), kore kru&scaron;ine (<em>Frangulae&nbsp;cortex</em>), lista pitome nane (<em>Mentha piperitae&nbsp;folium</em>), ploda kima (<em>Carvi fructus</em>) i lista breze&nbsp;(<em>Betulae folium</em>), kao i komercijalnog preparata Vitalplant<sup>&reg; </sup>((<em>Frangulae cortex</em>(35 %),&nbsp; <em>Mentha&nbsp;piperitae folium</em>(20%),&nbsp; <em>Carvi fructus</em>(20 %),&nbsp;<em>Petroselini fructus&nbsp;</em>(25 %)). U nastavku&nbsp;istraživanja ispitivana je antioksidantna aktivnosti etanolih ekstrakata primenom&nbsp;direktnih, ESR &ldquo;spin trap&ldquo; spektroskopskih&nbsp;metoda određivanja &ldquo;skevindžer&ldquo; aktivnosti na&nbsp;superoksid anjon i &nbsp;hidroksil radikale i&nbsp;indirektnih, spektrofotometrijskih testova za&nbsp;određivanje skevindžer&ldquo; aktivnosti na DPPH˙&nbsp;radikale, redoks potencijala i helatacione&nbsp;aktivnosti, kao i antioksidantne aktivnosti u&nbsp;sistemu&nbsp; &beta;-karoten-linolna kiselina. Osim navedenog, deo istraživanja je posvećen&nbsp;ispitivanju termičke stabilnosti ekstrakata&nbsp;navedenih biljaka i komercijalnog preparata&nbsp;Vitalplant<sup>&reg;&nbsp;</sup>radi sticanja uvida u mogućnost&nbsp;njihove primene u &nbsp;pekarskim proizvodima. U&nbsp;poslednjoj fazi rada, izvr&scaron;eno je određivanje sposobnosti pulvisa i etanolnog ekstrakta komercijalnog &nbsp;preparata Vitalplant<sup>&reg;</sup> da inhibiraju oksidaciju lipida u keksu, primenom spektrofotometrijskih testova &ldquo;skevindžer&ldquo; aktivnosti &nbsp;na DPPH˙ radikale i MDA testa. Ispitane biljne sirovine, kao i komercijalni preparat Vitalplant<sup>&reg;&nbsp;</sup>su bogat izvor jedinjenja iz klase biljnih fenola. Sve ispitane biljne droge poseduju antioksidantnu aktivnost, koja se značajno ne menja usled termičkog tretmana. Dodatak biljne me&scaron;avine Vitalplant<sup>&reg;&nbsp;</sup>, upravo proporcionalno njenom sadržaju, &nbsp;dovodi do povećanja antioksidantne aktivnosti keksa i smanjenja stepena lipidne peroksidacije.&nbsp;</p> / <p>In this paper, quantitative determination and identification of plant phenolics and flavonoids of ethanolic extracts obtained from parsley fruit (<em>Petroselini fructus</em>), buckthorn bark (<em>Frangulae cortex</em>), mint leaves (<em>Mentha piperitae folium</em>), caraway fruit&nbsp; (<em>Carvi fructus</em>), birch leaves (<em>Betulae folium</em>), as well as from commercial preparation Vitalplant&reg; ((<em>Frangulae cortex</em>(35 %), <em>Mentha piperitae folium</em>&nbsp;(20%), <em>Carvi fructus</em>(20 %), <em>Petroselini fructus&nbsp;</em>(25 %)) was performed. In addition, antioxidant&nbsp; activity of ethanolic extracts was tested, by applying direct, ESR &ldquo;spin trap&ldquo; &nbsp;spectroscopic methods for the determination of scavenging activity on superoxide anion and hydroxyl radicals, and indirect, spectrophotometric methods for the determination of DPPH˙ radical scavenging activity, reducing power, chelating activity and antioxidant activity in&nbsp; &beta;-carotene-linoleic acid model system. Moreover, thermal stability of the ethanolic extracts was tested in order to get insight into possible application of the extracts in bakery products. Finally, the ability of the commercial preparation Vitalplant&reg;, in the form of powder and extract, to inhibit oxidative changes of cookies was tested by applying spectrophotometric DPPH radical scavenging and MDA tests.</p><p>According to obtained results, investigated plant samples, including commercial preparation Vitalplant&reg;, are rich source of plant phenolics. Investigated plant drugs possess antioxidant activity, which is not significantly changed after the thermal treatment. Cookie supplementation with commercial preparation Vitalplant&reg; results in&nbsp; better oxidative stability of lipids and enhanced antioxidant activity of the cookies.</p>
175

Sekundarni biomolekuli u vrstama Allium sect. Codonoprasum Rchb. – biološke aktivnosti, fitohemijski i hemotaksonomski aspekti / Secondary metabolites from selected species of genus Allium sect. Codonoprasum Rchb. – biological activities, phytochemical and chemotaxonomic aspects

Simin Nataša 30 January 2015 (has links)
<p>U ovoj doktorskoj disertaciji ispitan je hemijski sastav i biolo&scaron;ke aktivnosti<br />ekstrakata deset&nbsp; samoniklih&nbsp; taksona roda&nbsp; <em>Allium</em>&nbsp; sect.&nbsp;<em> Codonoprasum:&nbsp; A. carinatum</em>&nbsp;subsp. <em>pulchellum,&nbsp; A. carinatum&nbsp;</em> subsp. <em>carinatum,&nbsp; A. fuscum&nbsp;</em> var. <em>gracile,&nbsp; A. fuscum&nbsp;</em> var.&nbsp;<em>fuscum,&nbsp; A. flavum</em> subsp. <em>flavum,&nbsp; A. melanantherum,&nbsp; A. paniculatum&nbsp;</em> subsp.&nbsp;<em> marginatum,&nbsp;A. pallens</em>&nbsp; subsp. <em>tenuiflorum,&nbsp; A. oleraceum&nbsp; </em>i&nbsp;<em> A. rhodopeum</em>, sakupljenih na&nbsp; 27 lokaliteta&nbsp;u Srbiji. Cilj rada bio je da se dobiju podaci o sadržaju biolo&scaron;ki aktivnih jedinjenja u&nbsp;ovim, do sada veoma malo ispitanim vrstama roda&nbsp; <em>Allium</em>, i utvrdi njihova potencijalna&nbsp;lekovita vrednost.</p><p>Analiza hemijskog sastava obuhvatila je: analizu volatilnih komponenti svežih&nbsp;<br />lukovica primenom headspace GC-MS tehnike, kvalitativnu analizu metanolnih &nbsp;<br />ekstrakata primenom tečnohromatografskih metoda (LC-DAD-MS i LC-MS-MS), &nbsp;<br />kvantitativnu analizu odabranih fenolnih jedinjenja LC-MS-MS tehnikom,&nbsp; određivanje&nbsp;sadržaja ukupnih&nbsp; monomernih&nbsp; antocijana&nbsp; i određivanje aktivnosti aliinaze. Ispitivanja&nbsp;biolo&scaron;kih aktivnosti ekstrakata obuhvatila su: određivanje antioksidantne,&nbsp;antiinflamatorne, antimikrobne, antimutagene i genotoksične aktivnosti, kao i ispitivanje&nbsp;uticaja na rast zdravih i tumorskih ćelija i sposobnosti indukcije ćelijske smrti.&nbsp;</p><p>Sumiranjem dobijenih rezultata može se zaključiti da ispitivani predstavnici roda&nbsp;<br /><em>Allium&nbsp;</em> sect.&nbsp; <em>Codonoprasum&nbsp;</em> predstavljaju bogate izvore biolo&scaron;ki aktivnih jedinjenja sa&nbsp;&scaron;irokim spektrom biolo&scaron;kih aktivnosti. Sa hemotaksonomskog aspekta značajno je da se&nbsp;dimetil-disulfid&nbsp; izdvaja kao&nbsp; najdominantnija&nbsp; i često jedina&nbsp; isparljiva komponenta, da&nbsp;ekstrakti većine vrsta&nbsp; sadrže veliku količinu flavonoida (prvenstveno derivata&nbsp;kvercetina), da se vrste&nbsp;<em> A. pallens&nbsp;</em> i&nbsp; <em>A. oleraceum</em>&nbsp; izdvajaju od ostalih po tome &scaron;to ne&nbsp;sadrže rutin&nbsp; a sadrže&nbsp; hiperozid,&nbsp; da je vrsta&nbsp;<em> A. rhodopeum</em>&nbsp; siroma&scaron;na fenolnim&nbsp;jedinjenjima i da su sve vrste, osim vrste&nbsp; <em>A.&nbsp; flavum</em>, bogate antocijanima. Aktivnost&nbsp;aliinaze je visoka u svim ispitivanim vrstama. Većina ispitivanih ekstrakata, izuzev&nbsp;ekstrakata vrsta&nbsp; <em>A. carinatum&nbsp;</em>i <em>A. melanantherum</em>, pokazala je izraženu antioksidantnu&nbsp;aktivnost, dok su ekstrakti vrsta <em>A. flavum</em>, <em>A. rhodopeum</em>, <em>A. oleraceum </em>i <em>A. paniculatum&nbsp;</em>snažni antiinflamatorni agensi. Ekstrakti ispitivanih predstavnika sect.&nbsp;<em> Codonoprasum&nbsp;</em>nisu pokazali antimikrobnu i antimutagenu aktivnost. Takođe, ovi ekstrakti nisu ispoljili&nbsp;genotoksični efekat na ćelije zdravog tkiva (izuzev slabog genotoksičnog efekta ekstrakta&nbsp;nadzemnih delova&nbsp;<em> A. flavum</em>), &scaron;to ukazuje na bezbednost upotrebe vrsta sect.&nbsp;<em>Codonoprasum&nbsp;</em> kao hrane ili u obliku lekova. Ekstrakti celih biljaka&nbsp;<em>A. paniculatum</em> i <em>A.&nbsp;rhodopeum</em>, kao i ekstrakt nadzemnih delova &nbsp;<em>A. melanantherum</em>&nbsp; pokazali su snažnu&nbsp;antiproliferativnu aktivnost sa povoljnim ne-tumor/tumor koeficijentima i indukovali&nbsp;apoptozu u tumorskim ćelijama, iz čega se može zaključiti da imaju visok potencijal&nbsp;primene u antitumorskoj terapiji.&nbsp;</p> / <p>In the present doctoral thesis the chemical composition and biological activities&nbsp; of&nbsp;<br />10 wild growing taxa of genus&nbsp; <em>Allium</em>&nbsp; sect. <em>Codonoprasum</em>&nbsp; (<em>A. carinatum&nbsp;</em> subsp.&nbsp;<br /><em>pulchellum,&nbsp; A. carinatum&nbsp;</em> subsp.&nbsp; <em>carinatum,&nbsp; A. fuscum&nbsp;</em> var.&nbsp; <em>gracile,&nbsp; A. fuscum</em>&nbsp; var.&nbsp;<br /><em>fuscum,&nbsp; A. flavum&nbsp;</em> subsp.&nbsp; <em>flavum,&nbsp; A. melanantherum,&nbsp; A. oleraceum,&nbsp; A. paniculatum</em><br />subsp. <em>marginatum, A. pallens</em> subsp. <em>tenuiflorum</em> and <em>A. rhodopeum</em>) were investigated.&nbsp;The samples were&nbsp; collected from 27 locations in Serbia. The aim of the study was to&nbsp;obtain data on the content of biologically active compounds in extracts of &nbsp;these&nbsp;unexplored species of the genus Allium and to determine their potential medicinal value.</p><p>Phytochemical caracterisation included: headspace GC-MS analysis of fresh bulb&nbsp;<br />volatiles, LC-DAD-MS and LC-MS-MS qualitative analysis of methanol extracts, LC-MS-MS quantitative analysis of 44 selected phenolic compounds in methanol extracts,&nbsp;determination of total monomeric anthocyanins content and alliinase activity. In order to&nbsp;assess the biological potential of methanol extracts, the antioxidant, anti-inflammatory,&nbsp;antimicrobial, antimutagenic, genotoxic and antiproliferative activities of &nbsp;the extracts&nbsp;were studied.</p><p>Summing up all the results obtained, it can be concluded that species of genus&nbsp;<em>Allium&nbsp;</em> sect.&nbsp; <em>Codonoprasum&nbsp;</em> are rich sources of biologically active compounds with a&nbsp;broad spectrum of biological activities. Dimethyl disulfide is the most dominant and&nbsp;often the only volatile component of most species, which is significant from&nbsp;chemotaxonomic point of view. The methanol extracts of investigated species contain&nbsp;high levels of flavonoids (primarily quercetin derivatives). Specificity of&nbsp; <em>A. pallens</em>&nbsp; and&nbsp;<em>A. &nbsp;oleraceum</em>&nbsp; extracts is that they do not contain rutin, but contain hyperoside, while&nbsp;small quantity of phenolic compounds&nbsp; is characteristic for&nbsp; <em>A. rhodopeum</em>&nbsp; extract. All&nbsp;investigated species, except of <em>A. flavum</em>, are rich in anthocyanins. Alliinase activity was&nbsp;high in&nbsp; all examined species. Most of the extracts, except&nbsp; <em>A. carinatum</em>&nbsp; and&nbsp; <em>A.&nbsp;melanantherum</em>&nbsp; extracts, express considerable antioxidant activity, &nbsp;while extracts of&nbsp;<em> A.&nbsp;flavum</em>,&nbsp; <em>A. rhodopeum</em>,&nbsp; <em>A. paniculatum</em>&nbsp; and&nbsp; <em>A. oleraceum&nbsp;</em> are potent anti-inflammatory&nbsp;agents. The investigated&nbsp; <em>Allium</em>&nbsp; extracts did not show antimicrobial and antimutagenic&nbsp;activity. Also, the extracts did not express genotoxic effect on healthy tissue cells&nbsp;(except the weak genotoxic effects of aerial parts extract of&nbsp; <em>A. flavum</em>), indicating that&nbsp;the use&nbsp; of these species as a food or as a drug is safe. Whole plant extracts of&nbsp; <em>A.&nbsp;paniculatum</em>&nbsp; and&nbsp;<em> A. rhodopeum</em>, as well as aerial parts extract of&nbsp;<em> A. melanantherum</em>&nbsp;showed strong antiproliferative activity (with a favorable &nbsp;non-tumor/tumor ratios) and&nbsp;induced apoptosis in tumor cells, suggesting that these plants have a high potential for&nbsp;application in antitumor therapy.</p>
176

Fitohemijska karakterizacija i biološka aktivnost odabranih vrsta tribusa Urticeae i Parietarieae (Urticaceae Juss.) / Phytochemical characterization and biological activity of selected species belonging to the Urticeae and Parietarieae tribe (Urticaceae Juss.)

Francišković Marina 21 July 2015 (has links)
<p>U okviru ove doktorske disertacije ispitan je hemijski sastav i biolo&scaron;ke aktivnosti metanolnih i vodenih ekstrakata odabranih samoniklih vrsta tribusa Urticeae, rod&nbsp; Urtica:&nbsp; U. <em>dioica</em>&nbsp; subsp.&nbsp; <em>dioica</em>&nbsp; var.&nbsp;<em> pubescens</em>, U.<em>&nbsp; dioica&nbsp;</em> subsp.&nbsp; <em>dioica&nbsp; </em>var.&nbsp; <em>dioica</em>&nbsp; i&nbsp; U. <em>kioviensis</em>&nbsp; i tribusa Parietarieae, rod&nbsp; Parietaria:<em>&nbsp; P. officinalis</em>,&nbsp; <em>P.</em><br /><em>lusitanica</em> L. subsp<em>. lusitanica</em>,<em> P. judaica</em> L. subsp. <em>judaica</em> i<em> P. serbica</em>. Cilj rada bio je da se odredi sadrţaj biolo&scaron;ki aktivnih jedinjenja u ovim, do sada veoma malo ispitanim vrstama famijije Urticaceae, i utvrdi njihov potencijal primene kao pomoćnih lekovitih sredstava i dodataka ishrani.<br />Hemijski sastav ekstrakata ispitivanih vrsta određen je primenom: tečnohromatografskih tehnika (LC-DAD-MS i LC-MS-MS) za kvalitativnu analizu metanolnih ekstrakata, dok je za kvantitativnu analizu odabranih fenolnih jedinjenja primenjena LC-MS-MS tehnika. Spektrofotometrijskim metodama je određen sadržaj<br />ukupnih fenolnih komponenti i flavonoida. Ispitivanja biolo&scaron;kih aktivnosti ekstrakata obuhvatila su: određivanje antioksidantne i antiinflamatorne aktivnosti kao i sposobnost ekstrakata da inhibiraju acetilholinesterazu.&nbsp; Određen je uticaj odabranih metanolnih ekstrakata na imuni odgovor i proliferaciju intestinalnih ćelijskih linija pacova (IEC18) i ĉoveka (Caco2).<br />Dobijeni rezultati ukazuju da odabrane vrste tribusa Urticeae i Parietarieae, odnosno rodova&nbsp; Urtica&nbsp; i Parietaria&nbsp; predstavljaju bogate izvore biolo&scaron;ki aktivnih jedinjenja koja ispoljavaju raznovrsne biolo&scaron;ke aktivnosti. Sa hemotaksonomskog aspekta izdvajaju se sledeća jedinjenja kao potencijalni taksonomski markeri: vi&scaron;i sadržaj 5-O-kafeoilhinske kiseline u ekstraktima herbi vrsta roda&nbsp; Urtica, i visok sadrţaj<br />epikatehina u ekstraktima korena vrsta roda&nbsp; Parietaria. Ekstrakt herbe vrste&nbsp; U. kioviensis&nbsp; se od ostalih izdvaja po tome &scaron;to ne sadrži rutin a sadrži&nbsp; C-glikozide, u najvećoj meri viteksin. Od svih ispitivanih ekstrakata, ekstrakti korena&nbsp; Parietaria&nbsp; vrsta su ispoljili najbolji antioksidantni potencijal u većini izvr&scaron;enih testova. Najsnažniji antiinflamatorni potencijal je ispoljio ekstrakt korena vrste&nbsp; P. officinalis&nbsp; a prate ga ekstrakti korena vrsta roda&nbsp; Urtica.&nbsp; Veoma dobar antiinflamatorni potencijal su ispoljili infuzi herbi vrste U.<em> dioica</em>&nbsp; (čajevi od koprive). Svi ispitani metanolni ekstrakti su ispoljili odličnu inhibiciju enzima acetilholinesteraze a kao najbolji se izdvajaju ekstrakti korena&nbsp; Parietaria&nbsp; vrsta i vrste&nbsp; U.<em> kioviensis</em>. Povećanu sekreciju citokina rat MCP1 i GRO&alpha;&nbsp; izazivaju ekstrakti korena vrsta&nbsp; P. officinalis&nbsp; i&nbsp; P. judaica&nbsp; u<br />bazalnim uslovima i uslovima LPS-stimulisane inlamacije, dok ekstrakti vrste&nbsp; U. dioica&nbsp; povećavaju bazalnu a smanjuju LPS-stimulisanu sekreciju. Stimulaciju sekrecije ova dva citokina, ispitivani ekstrakti vr&scaron;e interakcijom sa adapternim proteinom MyD88 (ali ne intereaguju sa TLR4 receptorom) i NF -&kappa;B signalnim<br />putem. Ekstrakt korena vrste&nbsp; P. <em>officinalis</em>&nbsp; povećava LPS-om indukovanu ekspresiju enzima COX-2 u IEC18 ćelijama, dok je ekstrakt korena vrste&nbsp; U.<em> dioica</em>&nbsp; smanjuje. Efekat epitelizacije ili zarastanja rane na monosloju IEC18 ćelija ispoljavaju ekstrakti herbe i korena vrste&nbsp; P. <em>officinalis</em>. Ispitivani ekstrakti ne menjaju značajno seksreciju citokina hMCP1 i IL-8 u Caco2 ćelijama niti ispoljavaju značajan uticaj na &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; njihovu proliferaciju.</p> / <p>Within this doctoral thesis the chemical composition and biological activity of methanol and aqueous extracts of the selected plant species belonging to the Urticeae and Parietarieae tribe, more specifically to the&nbsp; Urtica&nbsp; and&nbsp; Parietaria&nbsp; genuses was evaluated (Urtica:&nbsp; U.<em> dioica</em>&nbsp; subsp.<em> dioica</em>&nbsp; var.&nbsp; <em>pubescens</em>,&nbsp; U.&nbsp; <em>dioica</em>&nbsp; subsp.&nbsp;<em> dioica</em>&nbsp; var.&nbsp; <em>dioica</em>&nbsp; and&nbsp; U.<em> kioviensis</em>;&nbsp; Parietaria:&nbsp; P<em>. officinalis</em>,&nbsp; P.<em> lusitanica</em>&nbsp; subsp.&nbsp; <em>lusitanica,</em>&nbsp; P. <em>judaica&nbsp;</em> subsp.<em>&nbsp; judaica&nbsp;</em> and<em>&nbsp; P. serbica</em>). The principal aim was to determine the content of biologically active&nbsp; compounds in this, poorly<br />examined species of the Urticaceae family, and determine their potential as additional remedy and dietary supplements.<br />Qualitative analysis of methanol extracts was performed by LC-DAD-MS i LC-MS/MS analysis, and LC-MS/MS for quantitative analysis of selected phenolic compounds. Total phenolics and flavonoids were determined spectrophotometrically. In order to assess the biological potential, the antioxidant and anti-inflammatory activities of the extracts were studied as well as&nbsp; their ability to inhibit acetylcholinesterase. The immuno-modulatory effects of the selected methanol extract on the immune response and proliferation of intestinal epithelial cells (IEC18 and Caco2)<br />was determined.<br />The obtained results suggest that the examined species of the Urticeae and Parietarieae tribe (genuses&nbsp; Urtica&nbsp; and&nbsp; Parietaria) are abundant with the biologically active compounds that express a broad spectrum of biological activities. As a potential chemotaxonomic markers stand out the following&nbsp; compounds: 5-O-caffeoilquinic acid (highly abundant in the herb extracts of the&nbsp; Urtica&nbsp; spp.) and epicatechin (highly abundant in the root extracts of the&nbsp; Parietaria&nbsp; spp.).&nbsp; U.<br />kioviensis&nbsp; herb extracts differs from the rest by high content of vitexin and total lack of rutin. The best antioxidant potential have exhibited the root extracts of the&nbsp; Parietaria&nbsp; species. The strongest anti-inflammatory potential had the root extract of the&nbsp; P. officinalis, followed by root extracts of the&nbsp; Urtica&nbsp; spp. Excellent anti-inflammatory activity have exhibited the aqueous&nbsp; extracts of&nbsp; U.<em> dioica</em>&nbsp; herbs&nbsp; &ndash;&nbsp; stinging nettle teas. All tested methanol extracts have inhibited enzyme acetylcholinesterase, the best inhibitors being root extracts of&nbsp; U.<em> kioviensis&nbsp;</em> and Parietaria&nbsp; species. Root extracts of&nbsp; P<em>. officinalis</em>&nbsp; and&nbsp; P.<em> judaica</em>&nbsp; have increased the basal and LPS-stimulated secretion of rat MCP1 and GRO&alpha;, while&nbsp; U. <em>dioica&nbsp;</em> extracts increased the basal but decreased the LPS-stimulated secretion. The examined extracts interact with the MyD88 (but not the TLR4) and NF-&kappa;B signaling pathway. The root extract of&nbsp; P<em>. officinalis&nbsp; </em>increase LPS-stimulated expression of COX-2 in IEC18 cells, while the root extract of&nbsp; U<em>. dioica</em>&nbsp; decreases it.<br />The herb and root extract of P. <em>officinalis</em>&nbsp; exhibit the wound healing effect. Investigated extracts do not significantly alter the secretion of hMCP1 and IL-8 in Caco2 cells and exhibit no significant effect to their proliferation.</p> / null
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Identification of resistance sources and characterization of resistance factors in Brassica species to Verticillium longisporum / Identifizierung von Resistenzquellen und Charakterisierung von Resistenzfaktoren in Brassica-Arten gegenüber Verticillium longisporum

Eynck, Christina 31 January 2008 (has links)
No description available.
178

Imaging of fluorescence emission signals from healthy and infected leaf tissues / Imaging of fluorescence emission signals from healthy and infected leaf tissues

BENEDIKTYOVÁ, Zuzana January 2009 (has links)
Auto-fluorescence emission of plant tissues can be a powerful reporter on plant biochemistry and physiology since it originates in substances inherent to primary or secondary metabolism. Plant bodies contain a plethora of intrinsic fluorescent compounds emitting practically all wavelengths of visible light. Moreover, the spectrum of fluorescent reporter signals was recently extended by a variety of fluorescent proteins that provide a new tool to mark whole cells or sub-cellular structures, study protein localization and monitor gene expression and molecule interactions. The imaging of such fluorescence signals reveals a possibility to acquire the information from as many as millions of points simultaneously, in vivo and in a non-invasive way thereby preserving integrity of cells and whole organisms. Imaging is particularly suited to visualize heterogeneity such as a localized immune response to invading pathogens. It can be applied both at macro- as well as micro-scales in two and three dimensions. The recent advancement in microscopy, the multi-photon microscopy, has made possible to monitor fluorescence signals, such as NAD(P)H fluorescence from intact leaf interior, that have been hidden to single-photon techniques.
179

Wood Quality, Carbon and Nitrogen Partitioning, and Gene Expression Profiling in <i>Populus</i> Exposed to Free Air CO<sub>2</sub> Enrichment (FACE) and N-fertilization / Auswirkungen von CO<sub>2</sub>-angereicherter Luft im Freiland (FACE) und zusätzlicher Stickstoffdüngung auf die Holzqualität, Kohlenstoff- und Stickstoffverteilung, sowiedie Genexpression bei Pappeln

Luo, Zhibin 19 December 2005 (has links)
No description available.

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