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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.
201

Bistrenje soka šećerne repe primenom alternativnih koagulanata i flokulanata / Sugar beet juice clarification by means of alternative coagulants and flocculants

Kuljanin Tatjana 04 February 2008 (has links)
<p>Pri proizvodnji kvalitetnog belog konzumnog &scaron;ećera iz &scaron;ećerne repe, srećemo se sa problemom prisustva makromolekularnih jedinjenja u soku &scaron;ećerne repe koja su &scaron;tetna pa ih je neophodno odstraniti. Uklanjanje ovih jedinjenja, koja čine oko 60 % od ukupno sadržanih nesaharoznih materija u soku &scaron;ećerne repe, zasniva se&nbsp; na principu taloženja uz primenu različitih koagulanata (najče&scaron;će jedinjenja koja sadrže pozitivne jone kalcijuma). Međutim, afinitet vezivanja kalcijuma sa nepoželjnim makromolekulima iz soka &scaron;ećerne repe je mali, pa su potrebne velike količine ovog jedinjenja u svakodnevnoj proizvodnji &scaron;ećera.</p><p>Cilj istraživanja obuhvaćenih ovom doktorskom disertacijom usmeren je ka primeni alternativnih koagulanata sa dvo- i trovalentnim katjonima, pre svega soli aluminijuma i bakra koja izlazivaju proces razelektrisavanja makromolekula soka &scaron;ećerne repe.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Merenjem elektrokinetičkih potencijala utvrđene su optimalne količine koagulanata potrebne za uspe&scaron;nu koagulaciju makromolekularnih jedinjenja iz soka &scaron;ećerne repe. Ispitivan je i uticaj drugih procesnih veličina kao &scaron;to su pH, koncentracija makromolekula i uticaj brzine me&scaron;anja na efikasnost taloženja makromolekula.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Predložen je mehanizam razelektrisavanja makromolekularnih jedinjenja kao i model dvojnogelektričnog sloja koji okružuje&nbsp; koloidne čestice u soku &scaron;ećerne repe.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Ispitivana su dva model-rastvora komercijalno raspoloživih pektina u koncentracijama koje odgovaraju koncentracijama u soku &scaron;ećerne repe kao i jedan model-rastvor proteinskog preparata. Ispitivani sistemi su tretirani rastvorima CuSO<sub>4</sub>&nbsp;i Al2(SO<sub>4</sub>)<sub>3</sub> i rastvorima njihovih sme&scaron;a u različitim odnosima.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Dokazano je, za sva tri ispitivana preparata, da su manje količine Cu<sup>+2</sup> jona u odnosu na Al<sup>+3</sup><sup>&nbsp;</sup>jone potrebne za sniženje vrednosti Zeta potencijala na nulu. Međutim, zbog mogućih nepoželjnih efekata CuSO<sub>4</sub>&nbsp;u obradi hrane, Al(SO<sub>4</sub>)<sub>3</sub> bi se mogao upotrebiti umesto tradicionalnog koagulanta CaO, kako zbog manje potro&scaron;nje koagulanta, tako i zbog očuvanja životne sredine.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Cilj eksperimenata sa sme&scaron;ama je ispitivanje mogućnosti pobolj&scaron;anja koagulacionih karakteristika često kori&scaron;ćene soli&nbsp;Al2(SO<sub>4</sub>)<sub>3</sub>, dodavanjem malih količina Cu<sup>+2</sup> jona. Međutim, čiste soli su pokazale bolja koagulaciona svojstva.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Istraživanja sa flokulantima, odnose se na odabiranje najpogodnijeg tipa i optimalne količine flokulanata, uz primenu predloženih koagulanata. Najveća efikasnost či&scaron;ćenja soka &scaron;ećerne repe, uočena je nakon primene anjonskog flokulanta koncentracije 3 mg/dm<sup>3</sup>. Dokazano je da ovaj tip flokulanata dodatno smanjuje vrednost Zeta potencijala prisutnih makromolekula čime se smanjuje potrebna količina ispitivanih koagulanata&nbsp;&nbsp;CuSO<sub>4 </sub>i&nbsp;Al(SO<sub>4</sub>)<sub>3</sub>.</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p><p>&nbsp;</p><p><br /><br />&nbsp;</p><p>&nbsp;</p> / <p>During production of full quality consumed white sugar from sugar beet, there is a problem of the presence<br />of macrom olecular compounds in sugar beet juice, which are harmful and we have to be removed.<br />Separation ofthese compounds, which make around 60% oflotal non-sucrose compounds in sugar beetjuice,<br />is done by the principle of sedimentation with different types of coagulants (mostly compounds with calcium<br />ion). However, affinity of calcium binding with undesirable macromolecules fiom sugar beet juice is not<br />significant and in that way it is necessary a lot of quantities of this compound throughout daily production of<br />sugar.<br />The aim of this doctoral thesis is to consider the application of alternative coagulants with divalent and<br />trivalent cations, especially the salt of aluminum and cooper, which cause the process of dischargeable<br />macromolecules in sugar beet juice.<br />Optimal quantities of coagulants needing for the efficient coagulation of macromolecules compounds from<br />sugar beet juice were determined by means of measuring of electrokinetic potentials. It was investigated the<br />influence of other process variables such as pH, concentration of macromolecules and the impact of speed<br />mixing on the efficiency of sedimentation of macromolecules.<br />Mechanism of discharge of macromolecules compounds as well as the model of double electric layer<br />surrounding colloidal particles in sugar beetjuice are suggested for sugar beetjuice clarification.<br />Two model solutions of pectin are investigated together with one model solution of protein. Their<br />concentration correspond to concentration of these macromolecules in sugar beet juice. All investigated<br />systems were treated by using both solutions of CuSO4 as well as Al2(SO4)3 and slutions of their mixtures in<br />different proportion.<br />It was proven for all three investigated samples that fewer quantities of Cu+2 ions compared to the values of<br />Al+3 ions are needed to reach zero Zeta potential. However, due to possible undesirable effects of CuSO4 on<br />food processing, Al2(SO4)3 is proposed instead of traditional coagulant CaO, not only because of lower<br />consumptions of coagulants but owing to protection of the environment.<br />The objective in the experiments with mixtures was to investigate enhancement of coagulated characteristics<br />with commonly used salt Al2(SO4)3 by adding small quantities of Cu+2 ions. It was proven that pure salts<br />showed better-coagulated properties.<br />Further investigation was focused to selection of the most appropriate type and optimal quantity of chosen<br />flocculants. The highest efficiency of clarification of sugar beet juice was noticed by applying anion<br />flocculants of concentration 3 mg/dm3. It was shown that this type of flocculants additionally decreased the<br />value of Zeta potential of present macromolecules which further reduce required quantity of investigated<br />coagulants CuSO4 and Al2(SO4)3.</p>
202

Uticaj procesa osmotske dehidratacije na promene mikrobiološkog profila dehidriranog poluproizvoda od pilećeg mesa / The Effect of Osmotic Dehydration Process on Microbiological Profile Changes of Dehydrated Chicken Meat Semi-product

Filipović Ivana 30 September 2020 (has links)
<p>Ispitivan je uticaj vrednosti procesnih parametara: na tehnolo&scaron;ku efikasnost procesa osmotske dehidratacije pilećeg mesa u vodenom rastvoru NaCl i saharoze i melasi; na nivo redukcije odabranih mikroorganizama (Escherichia coli, Salmonella spp., Listeria monocytogenes) u osmotskim rastvorima; na mikroorganizme prisutne na dehidrirajućem pilećem mesu; istraživana je podobnost osmotski dehidriranog pilećeg mesa za rast i razmnožavanje odabranih mikroorganizama tokom perioda skladi&scaron;tenja, uz definisanje zdravstveno bezbednog roka skladi&scaron;tenja na osnovu mikrobiolo&scaron;kih i hemijskih analiza.<br />Rezultati ispitivanja pokazuju da povećanje vrednosti procesnih parametara temperature, vremena trajanja procesa i koncentracije osmotskih rastvora dovodi do intenziviranja prenosa mase između dehidrirajućeg materijala i rastvora i povećanja efikasnosti procesa. Izlaganjem odabranih mikroorganizma osmotskim rastvorima postignuti su visoki nivoi njihove redukcije. U melasi postignuti su vi&scaron;i nivou redukcije mikroorganizama u poređenju sa vodenim rastvorom. Ostvareni nivoi redukcije odabranih mikroorganizama na pilećem mesu tokom procesa niži su u poređenju sa rezultatima redukcionih odnosa istih mikroorganizama direkno inokulisanih u istim osmotskim rastvorima. Sa protokom vremena skladi&scaron;tenja ve&scaron;tački kontaminiranog i osmotski dehidriranog pilećeg mesa, u oba osmotska rastvora, do&scaron;lo je do smanjenja broja svih ispitivanih mikroorganizama. Proteolitički mikroorganizami nisu bili prisutni u dehidranom pilećem mesu, dok sadržaj histamina je pokazao da, tokom vremena skladi&scaron;tenja, nije dolazilo do degradacije proteina u mesu. Nakon 10 dana skladi&scaron;tenja meso nije bilo užeglo, a vrednosti malondialdehida su ukazale na pojavu užegnuća nakon 14 dana skladi&scaron;tenja.<br />Na osnovu dobijenih rezultata razvijeni su modeli zavisnosti odziva procesa osmotske dehidratacije, nivoa redukcije ispitivanih mikroorganizama u osmotskim rastvorima, nivoa redukcije ispitivanih mikroorganizama na dehidriranom pilećem mesu i mikrobiolo&scaron;kih i hemijskih odziva dehidriranog pilećeg mesa tokom skladi&scaron;tenja u zavisnosti od variranih vrednosti parametara procesa.<br />Na osnovu dobijenih rezultata, kao optimalni parametri, mogu da se defini&scaron;u: trajanje procesa od 5 časova, temperatura od 32&deg;C u melasi, kao osmotskom rastvoru, maksimalne koncentracije. Svi postignuti nivoi redukcije mikroorganizama ukazuju na dobru osnovu za proizvodnju zdravstveno bezbednih proizvoda od pilećeg mesa. Analiza održivosti je pokazala da je osmotski dehidriranom pileće meso mikrobiolo&scaron;ki i hemijski stabilno tokom skladi&scaron;tenja na temperaturi od 22 &deg;C u trajanju od najmanje 10 dana.</p> / <p>The effect of process parameters values on: technological efficiency of chicken meat osmotic dehydration process in water solution of NaCl and succrose and molasses; selected microorganisms (Escherichia coli, Salmonella spp., Listeria monocytogenes) in osmotic solutions reduction levels; selected microorganisms on dehydrating chicken meat reduction levels, is investigated. The osmodehydrated chicken meat suitability for selected microorganisms&rsquo; growth and multiplication during storage period is also investigated, together with defining health safe storage period, on the basis of microbiological and chemical analysis.<br />Results shows that increase of process parameters of temperature, duration and osmotic solutions&rsquo; concentrations leads to mass transfer increase between dehydrating material and osmotic solutions and process efficiency increase. Exposure of selected microorganisms to osmotic solution has led to high levels of reductions of their numbers. Processes in molasses had higher levels of microorganisms&rsquo; reductions in comparison to the water solution. Achieved levels of the selected microorganisms&rsquo; on chicken meat reductions were lower in comparison to the results of reduction of the same microorganisms directly inoculated in the same osmotic solutions. With the increase of the inocualted, osmotically dehydrated chicken meat storage time in both osmotic solutions, decrease of all tested microorganisms occured. Proteolytic microorganisms were not detected in dehydrated chiken meat, while histamin content showed that, during storage, there was no meat protein degradation. After 10 days of storage, meat was not rancid, while malondialdehid values showed that lipid oxidation occured after 14 days of storage. On the basis of obtained results, mathematical models of dependance of: osmotic dehydration process responces; selected micororganisms in osmotic solutions reduction levels; selected microorganisms on osmodehydrated chicken meat reduction levels; and osmodehydrated chicken meat during storage microbiological and chemical responces; from varied process parameters, were developed.<br />Based on obtained results, as optimal process parameters it can be defined: 5-hour process, at 32 &deg;C, in molasses of maximal concentration, as osmotic solution. All achived microorganisms&rsquo; reduction levels can indicate on good basis of health safe chicken meat production. Analysis of storage duration has shown that osmotdehydrated chicken meat is microbilogicaly and chemicaly stabile during sotrage at 22 &deg;C in period of at least 10 days.</p>
203

Uticaj prehrambenih vlakana šećerne repe i jabuke na reološke parametre testa i kvalitet bezglutenskog hleba / Influence of sugar beet and apple dietary fibres on batter rheology and gluten free bread quality

Đorđević Marijana 25 September 2020 (has links)
<p>Sagledavajući značaj nutritivne vrednosti bezglutenskog hleba u prevenciji dodatnih zdravstvenih poremećaja kod obolelih od celijakije, kao i prisutnog trenda bezglutenske ishrane, u okviru ove disertacije analizirana je mogućnost obogaćenja bezglutenskog hleba prehrambenim vlaknima. Ispitan je uticaj različite vrste i količine (3, 5, 7%) prehrambenih vlakana (vlakna &scaron;ećerne repe i vlakna jabuke), količine hidroksipropil metil celuloze - HPMC (2, 3, 4%) i količine vode (180&ndash;230%) na reolo&scaron;ke osobine bezglutenskog testa (svojstva proticanja i viskoelastične osobine), kvalitet i nutritivnu vrednost bezglutenskog hleba. Rezultati ove disertacije ukazuju da dodatak vlakana &scaron;ećerne repe i jabuke ne umanjuje pozitivan uticaj HPMC na reolo&scaron;ke osobine bezglutenskog testa, formiranje i ojačavanje njegove strukture. Bezglutenski hleb privlačne boje, veće zapremine, manje tvrdoće sredine i odličnih senzorskih karakteristika dobijen je kod uzoraka sa 4% HPMC, 3, 5 ili 7% vlakana &scaron;ećerne repe/jabuke i 220%/190% vode. Sadržaj ukupnih prehrambenih vlakana kod uzoraka sa 3% vlakana je iznad 4,5 g/100 g, a kod uzoraka sa 7% vlakana čak oko 6 g/100 g bezglutenskog hleba. Postignut sadržaj ukupnih prehrambenih vlakana je iznad propisane vrednosti za proizvode koji mogu biti nosioci nutritivne izjave &bdquo;izvor vlakana&ldquo;, čime je ostvaren cilj ove disertacije.</p> / <p>Considering the importance of the gluten-free bread nutritional value in the prevention of additional health disorders in patients with celiac disease, as well as the arising gluten-free diet trend, the possibility of enriching gluten-free bread with dietary fibers was analyzed within this dissertation. The influence of different types and amounts (3, 5, 7%) of dietary fibers (sugar beet and apple fibers), the amount of hydroxypropylmethylcellulose - HPMC (2, 3, 4%) and the amount of water (180&ndash;230%) on rheological properties of gluten-free batter (flow and viscoelastic properties), quality and nutritional value of gluten-free bread. The results of this dissertation indicate that the addition of sugar beet and apple fibers does not diminish the positive influence of HPMC on the rheological properties of the gluten-free batter, the formation and strengthening of its structure. Gluten-free bread with appealing color, higher volume, lower hardness and excellent sensory characteristics was obtained in samples with 4% HPMC, 3, 5 or 7% sugar beet/apple fibers and 220%/190% water. The total dietary fibers content in samples with 3% fibers is above 4.5 g/100 g, and in samples with 7% fibers approximately 6 g/100 g of gluten-free bread. The accomplished total dietary fibers content is above the prescribed value for products that may bear the nutritional statement &quot;source of fiber&quot;, thus achieving the goal of this dissertation.</p>
204

Entwicklung eines FISH-Referenzkaryotyps der Zuckerrübe (Beta vulgaris) für die Integration genetischer Kopplungskarten und die Analyse der chromosomalen Verteilung von repetitiven Sequenzen

Päsold, Susanne 19 December 2013 (has links)
Die Verbindung von genetischen, physikalischen und zytologischen Daten ist entscheidend für die Genom- und Chromosomenanalyse. Obwohl Beta vulgaris (2n = 18) als wichtige Kulturpflanze und Untersuchungsobjekt der Grundlagenforschung eine intensiv analysierte Art darstellt, existiert bisher keine Verknüpfung zwischen Kopplungsgruppen (LG) und Chromosomen. B.-vulgaris-Chromosomen können zudem aufgrund fehlender morphologischer Unterscheidungsmerkmale bisher nicht einzeln identifiziert und klassifiziert werden. Somit sind zytogenetisch gewonnene Ergebnisse nicht ohne weiteres auf genetische Kopplungsgruppen und physikalische Karten übertragbar. Zytogenetische Methoden können zur Analyse struktureller Chromosomenveränderungen, zur Identifizierung und Lokalisierung von repetitiver DNA sowie zur Kartierung schwierig zu positionierender Marker verwendet werden. Ziel dieser Arbeit war es daher, ein FISH (Fluoreszenz-in-situ-Hybridisierung)-Verfahren zu etablieren, das die Kopplungsgruppen und Chromosomen der Zuckerrübe korreliert und die mikroskopische Identifizierung aller Chromosomenarme ermöglicht. Im Rahmen dieser Arbeit wurde ein FISH-Referenzkaryotyp der Zuckerrübe entwickelt. Durch ein Sondenset aus 18 BACs (bacterial artificial chromosome) sind alle Chromosomenarme der Zuckerrübe identifizierbar und werden mit den nördlichen und südlichen Enden der genetischen Kopplungsgruppen verknüpft. Somit ist eine einheitliche Nummerierung von Kopplungsgruppen und Chromosomen möglich. Durch die gleichzeitige Hybridisierung von chromosomenspezifischen BACs und den Satelliten-DNA-Sonden pAv34 und pBV VI beziehungsweise pEV und pBV wurden die Verteilungsmuster der Sequenzfamilien auf den Chromosomen ermittelt. Die gleichzeitige Hybridisierung aller vier repetitiven Sonden ergab ein chromosomenspezifisches Muster aus subtelomerischen, interkalaren und zentromerischen Signalen. Damit ist die Identifizierung aller B.-vulgaris-Chromosomen in einem einzelnen FISH-Experiment möglich. Zudem wurden dadurch die Chromosomen mit hohem Anteil an tandemartig angeordneten repetitiven Sequenzen identifiziert und die Chromosomenregionen lokalisiert, welche die Sequenzassemblierung behindern können. Sowohl das entwickelte BAC-Set als auch der Sondenpool aus repetitiver DNA unterscheiden die somatischen Metaphasechromosomen erstmals unabhängig von trisomen Linien. Da mit Hilfe der Satelliten-DNA-Sonden alle Chromosomen gleichzeitig markiert werden können, waren die spezifischen physikalischen Längen ermittelbar. Sie wurden mit den genetischen Längen der Kopplungsgruppen in Verbindung gebracht und deckten eine kopplungs-gruppenspezifische Rekombinationshäufigkeit zwischen 0,73 und 1,14 Mb/cM auf. Durch Hybridisierung der BACs und subtelomerischer beziehungsweise telomerischer Sonden auf Pachytänchromosomen wurde der Abstand der BACs sowie der in ihnen enthaltenen genetischen Marker zum physikalischen Chromosomenende abgeschätzt. An fünf Chromo-somenenden wurde ein deutlicher Abstand zwischen den Signalen des BACs und der terminalen Sonden festgestellt. Die zugehörigen Kopplungsgruppen sind demnach erweiterbar. Zudem wurden drei BACs mit nicht detektierbarem Abstand zum Chromosomenende durch FISH an gestreckten Chromatinfasern näher untersucht. Einer der drei BACs wurde eindeutig in unmittelbarer Nähe des Telomers nachgewiesen. Für dieses Ende (Chr 2N) ist die Wahrscheinlichkeit gering, dass die Kopplungsgruppe durch zusätzliche Marker erweitert werden kann; sie wird darum als abgeschlossen angesehen. Für die Enden Chr 4S und Chr 9S war der Abstand zwischen BAC und terminaler Sonde zu groß, um ihn durch Fiber-FISH zu ermitteln. Für sie sind weitere distal zu positionierende Marker wahrscheinlich. Weiterhin wurden bioinformatische Analysen an der verfügbaren B.-vulgaris-Genomsequenz RefBeet 1.0 durchgeführt. Scaffolds, welche die genetischen terminalen Marker enthalten, wurden bioinformatisch identifiziert und auf ihren Gehalt subtelomerischer und telomerischer Sequenzen untersucht. Vorhandene terminale Sequenzen sind ein Nachweis für eine terminale Lokalisierung der in-silico-Chromosomenabschnitte. Für drei Scaffolds mit zuvor ungeklärter Lage wurde dadurch das in-silico-Chromosom ermittelt beziehungsweise die nördliche oder südliche Position auf dem Chromosom dargestellt. Durch die Lokalisierung dieser Bereiche innerhalb der Sequenz in Bezug zum genetischen Marker und unter Berücksichtigung der Ergebnisse der Pachytän-FISH wurde die Strangorientierung von 16 Scaffolds ermittelt. Auf 14 Scaffolds wurden die Abstände der Marker zu den terminalen Sequenzen bestimmt. Der Median betrug etwa 196 kb. Für alle Kopplungsgruppenenden außer dem Norden von LG 2 und LG 4 ist das Vorhandensein weiterer distaler genetischer Marker wahrscheinlich. Satelliten-DNA ist innerhalb einer Art meist homogen, kann jedoch chromosomenspezifische Varianten ausbilden. Auf dem BAC-Marker für Chr 2N wurde durch Southern-Hybridisierung die subtelomerische Sequenzfamilie pAv34 detektiert. Von dem betreffenden BAC wurde eine Subklonbank erstellt. Durch Southern-Hybridisierung wurde der pAv34-Gehalt der Subklone analysiert. Positive Klone wurden sequenziert. Dabei wurden vier verschiedene vollständige pAv34-2N-Monomere detektiert. Im Vergleich mit pAv34-Volllängenmotiven aus der RefBeet 1.0 und dem Datensatz der nicht assemblierten Sequenzen der RefBeet 0.2 bilden die pAv34-2N-Einheiten mit pAv34-Kopien, die verschiedenen in-silico-Chromosomen und Contigs zugeordnet sind, eine Subfamilie. Aus den Sequenzen der Subklone wurden zwei Subklon-Contigs gebildet, die im in-silico-Chromosomenabschnitt von Chr 2N (Bvchr2.un.sca001) positioniert wurden. Dadurch wurden Regionen bisher unbekannter Sequenz entschlüsselt. Abweichungen zwischen den assemblierten Daten und den Subklonsequenzen deuten auf Assemblierungsfehler der Genomsequenz in repetitiven Bereichen hin. Die in dieser Arbeit erzielten Ergebnisse ermöglichen erstmalig die eindeutige Identifizierung aller B.-vulgaris-Chromosomen unabhängig vom Zellzyklusstadium und im Einklang mit genetischen Informationen. Zytogenetische sind jetzt mit molekularen Daten integrierbar und können verwendet werden, um den chromosomenspezifischen Satelliten-DNA-Gehalt aufzudecken und mögliche chromosomenspezifische Subfamilien zu identifizieren. Sie erlauben, physikalische Abstände zwischen Markern zu ermitteln und die Abdeckung von Kopplungsgruppen im terminalen Bereich zu untersuchen. Die Ergebnisse tragen dazu bei, Marker und nicht zugeordnete Contigs und Scaffolds zu kartieren, Ursachen für Lücken aufzudecken und damit die Sequenzdaten des Zuckerrübengenoms zu einer fortlaufenden, hochqualitativen Sequenz zu assemblieren. Die zytogenetischen Daten bilden zudem die Basis für zukünftige Untersuchungen struktureller Umbauten von Chromosomen, die während der Genomevolution stattfanden. / The correlation of genetic, physical and cytological data is crucial for interdisciplinary genome and chromosome analyses. Beta vulgaris (2n = 18) is an important crop and an object of basic research. Although it is an intensely analysed species, its genetic linkage groups (LG) have not been assigned to chromosomes. Additionally, sugar beet chromosomes lack distinct morphological features and could therefore not be identified and classified individually. Consequently, results generated by cytogenetic methods can not be readily applied to genetic and physical maps. Cytogenetic approaches enable analysing structural chromosomal changes, identifying and localizing repetitive DNA, and mapping of markers which are difficult to place within linkage maps. Therefore, the main objective of this work has been the development of a FISH (fluorescence in situ hybridization) procedure that correlates LGs with chromosomes of sugar beet and that allows the microscopic identification of individual chromosome arms. In this work a FISH reference karyotype for sugar beet has been established. A set of 18 BACs (bacterial artificial chromosome) allows the unequivocal identification of each sugar beet chromosome and assigns them to the southern and northern ends of LGs. Hence, the chromosomes are numbered in accordance with the genetic map. The arm-specific BACs and the satellite DNA families pBV and pBV VI or pEV and pAv34 have been hybridized simultaneously to assign the distribution patterns of the highly abundant sequence families to chromosomes. Simultaneous hybridization of the four repetitive probes revealed a chromosome-specific pattern of subtelomeric, intercalary and centromeric signals. Thus, each of the sugar beet chromosomes can be identified in a single FISH experiment. Furthermore, chromosomes with a high content of repetitive DNA have been identified and chromosomal regions that may hinder the correct sequence assembly have been localized. The BAC set as well as the pooled satellite DNA probes discriminate the somatic chromosomes for the first time independently from trisomic lines. Since the chromosomes are differentially labelled with the satellite DNA probes their physical distances could be determined and correlated with genetic distances of the corresponding LGs. A LG-specific recombination frequency from 0.73 to 1.14 Mb/cM has been disclosed. BACs and subtelomeric or telomeric sequences have been hybridized simultaneously on pachytene chromosomes to estimate distances between BACs plus the markers they contain and the physical chromosome ends. Five BACs showed substantial distances to the physical chromosome ends; the corresponding LGs could thus be extended by additional markers. Furthermore, three BACs showing only minor distances to chromosome ends have been investigated in detail by fiber-FISH. One of these BACs was localized closely adjacent to the telomere. For this chromosome end (Chr 2N) it is unlikely that the LG could be extended distally by additional markers and is therefore considered to be closed. The BACs for the chromosome ends Chr 4S and Chr 9S have been too distant from the terminal probe to be bridged by fiber-FISH. For them it is likely that further markers can be placed distally. Furthermore, the B. vulgaris genomic sequence RefBeet 1.0 has been investigated. Scaffolds containing terminal genetic markers have been identified bioinformatically and analysed for the content of subtelomeric and telomeric sequences. The occurrence of terminal sequences confirms the terminal localization of in silico chromosome segments. Three scaffolds with an initially unknown position could thus be allocated to in silico chromosomes and to the northern or southern position on the chromosome. The strand orientation of 16 scaffolds has been determined based on the localization of terminal sequences in relation to the genetic marker considering the results of FISH on pachytene chromosomes. The distance between markers and terminal sequences has been determined for 14 scaffolds. The median is 196 kb. It is likely that further markers can be placed distally from all LG ends except for the north of LG 2 and LG 4. Satellite DNA is usually homogenous within one species; however, it can form chromosome-specific variants. Southern hybridization revealed that the BAC marker for Chr 2N contains the subtelomeric sequence family pAv34. The BAC has been subcloned and the pAv34 content of the subclones has been analysed by Southern hybridization. Positive clones have been sequenced. Thereby, four pAv34-2N monomeres have been detected. Compared to full-length pAv34 motives derived from the RefBeet 1.0 and from unassembled sequence data of the RefBeet 0.2 the pAv34-2N units form a subfamily together with pAv34 copies assigned to different in silico chromosomes and contigs. The subclone sequences have been assembled to two subclone contigs, which have been positioned within the in silico chromosome segment of Chr 2N (Bvchr2.un.sca001). Thereby, regions of unknown sequence have been decoded and probable misassemblies in repetitive regions within the RefBeet 1.0 have been disclosed. The results obtained in this work enable the identification of all sugar beet chromosomes independently from their stage of cell division and in accordance with genetic information. Cytogenetic data are integrated with molecular data and can be used for identifying the chromosome-specific distribution of repeats and chromosome-specific repeat variants. They enable determining physical distances between markers and investigating the terminal coverage of LGs. The results support the correct mapping of markers and unassigned contigs, uncover reasons for gaps within maps and sequence assemblies, and thus contribute to assembling data into a continuous high quality genome sequence of sugar beet. Moreover, the cytogenetic data represent the basis for future investigations of structural chromosomal changes that took place during evolution.
205

Repression der cytosolischen GS1 von Zuckerrüben (Beta vulgaris L. var. altissima) durch Antisense-DNA-Konstrukte / Repression of the cytosolic GS1 from sugar beet (Beta vulgaris L. cv. altissima) by using antisense DNA constructs

Hoffmann, Guido Wolf 21 June 2000 (has links)
No description available.
206

Epidemiologie von Cercospora beticola Sacc. und Befalls-Verlust-Relationen bei Zuckerrüben (Beta vulgaris L.) in Abhängigkeit von der Anfälligkeit von Sorten und Konsequenzen für sortenspezifische Bekämpfungsschwellensysteme / Epidemiology of Cercospora beticola Sacc. and disease-loss relationship in sugar beet (Beta vulgaris L.) depending on the susceptibility of cultivars and consequences for cultivar specific threshold systems

Kaiser, Ulrike 19 July 2007 (has links)
No description available.
207

Erfassung von Resistenz und Toleranz gegen den Rübenzystennematoden (Heterodera schachtii) in Feldversuchen mit Zuckerrüben und Einfluss einer resistenten Sorte auf die Entwicklung des Nematoden sowie auf seine pilzlichen Eiparasiten / Registration of resistance and tolerance against the sugar beet nematode (Heterodera schachtii) in field trials with sugar beets and influence on a resistant sugar beet variety on the development of nematodes and his fungal parasites in soil.

Balke, Tina 22 November 2001 (has links)
Seit 1998 ist erstmals eine gegen Heterodera schachtii resistente Zuckerrübensorte in Deutschland zugelassen. Diese wurde in einem dreijährigen Versuchsprogramm (1998-2000) an vier Standorten in unterschiedlichen Regionen Deutschlands angebaut, um methodische Fragen sowie die Auswirkung auf die Nematodenpopulation zu untersuchen. Unter Nematodenbefall reagierte die resistente Zuckerrübe mit einer konstanten Ertragsleistung, war also tolerant. Auf den vier Standorten kam es unter der resistenten Sorte zu keiner bzw. nur geringer Nematodenvermehrung.Die Resistenz der Sorte wurde im Biotest anhand der Transmissionsrate beurteilt. Auf 92-95 % der Pflanzen aus der Versuchssorte wurde das Resistenzgen übertragen, lediglich ein geringer Anteil von 5-8 % war anfällig. In Feldversuchen wurden die unter kontrollierten Bedingungen ermittelten Übertragungsraten nur teilweise bestätigt; zufällig bedingte Varianzen waren möglicherweise die Ursache.Um abgesicherte Aussagen über das Resistenz- und Toleranzniveau der Versuchssorte zu erhalten, muss ein Mindestaufwand bei den Untersuchungen eingehalten werden (Mischprobe aus 40 Bodeneinstichen je Parzelle von ca. 10 m2 Größe, davon ist ca. 1,8 kg Boden zu untersuchen). Auf dieser Basis können das Ertragsniveau der Sorte und ihre Auswirkung auf die Nematodenpopulation mit Hilfe von Regressionskurven beschrieben werden. Wenn dieser Aufwand aus ökonomischen Gründen nicht möglich ist, erscheint eine Reduzierung auf 900 g Boden noch vertretbar, führt allerdings zu verringerter Aussagesicherheit.Die Resistenz hatte keinen Einfluss auf die Anzahl der in die Wurzeln ein- bzw. ausgewanderten Larven. An den resistenten Zuckerrüben entwickelten sich mehrheitlich Männchen aber kaum Weibchen. Der Resistenzmechanismus beeinflusst also die geschlechtliche Entwicklung des Nematoden. Allerdings war eine erhöhte Männchenanzahl an resistenten Zuckerrüben nicht nachweisbar. Der Resistenzmechanismus führt wahrscheinlich zu einer frühzeitigen Stagnation weiblicher Larven. Der Einfluss eines mehrmaligen Anbaus einer resistenten Sorte auf das Potenzial pilzlicher Nematodenantagonisten im Boden wurde bei fünfmaligem Anbau der Sorte auf demselben Boden untersucht (zweimal Beprobung aus Feld- und dreimal aus Gewächshausanbau). Dabei lag die Parasitierungsrate der Nematodeneier in Feldböden bei der resistenten Sorte deutlich niedriger als bei anfälligen Zuckerrüben. Diese Beeinträchtigung pilzlicher Eiparasiten hat lediglich einen vorübergehenden Charakter, da die Raten nach erneutem Anbau anfälliger Pflanzen wieder ansteigen. Die absolute Anzahl parasitierter Eier und Larven war mit der Populationsdichte des Nematoden positiv korreliert; vermutlich werden pilzliche Eiparasiten durch ein erhöhtes Nahrungsangebot gefördert.
208

Cukrovarnický průmysl v České republice - geografická analýza / Sugar industrie in Czech Republic - geography analisis

STEINBAUEROVÁ, Simona January 2010 (has links)
This thesis deals with a growing trend of the sugar industry in the Czech Republic. The first part of the work is focused on analysing of the agriculture aspects of the cane sugar cultivation. The following chapters are given to the world sugar production. The most important section the thesis is focused on development of the sugar industry and cultivation of sugarbeet in the Czech Republic, i.e development of the acreage of sugarbeet, rate of sugarbeet acreage on czech districts. Final part is given to the analysing of the sugar industry restrukturalization and influence of the European Union on the common trade of the given industry.
209

Application des électrotechnologies pour une valorisation optimisée de la betterave à sucre dans un concept de bioraffinerie / Application of electrotechnologies for an optimized valorization of sugar beet in biorefinery concept

Almohammed, Fouad 24 January 2017 (has links)
Ce travail de thèse concerne l’utilisation des électrotechnologies pour une valorisation optimisée de la betterave à sucre conformément au concept de bioraffinerie. Les électro-technologies appliquées sont les champs électriques pulsés (CEP) et les décharges électriques de haute tension (DEHT). L’étude s’attache d’une part à l’optimisation d’un procédé alternatif pour l’extraction du sucre par pressage alcalin à froid assisté par CEP. D’autre part, elle propose des nouvelles voies pour la valorisation de deux coproduits de l’industrie betteravière qui sont les radicelles et la pulpe de betterave. Dans la première partie, le traitement électrique par CEP couplé au chaulage permet une meilleure désintégration du tissu betteravier. Il permet d’accélérer les cinétiques du pressage, d’améliorer le rendement ainsi que la qualité du jus et d’alléger la procédure de purification en aval de l’extraction. Une étude paramétrique d’optimisation a permis d’identifier le meilleur itinéraire d’application de ce nouveau procédé d’extraction. Les cossettes fraîches de betterave sont prétraitées par CEP à 600 V/cm pour 10 ms (Q = 2,7 Wh/kg). Les cossettes électroporées sont ensuite pressées à froid pour extraire 75 % du jus. Les cossettes pressées subissent un pressage alcalin avec 10 % du lait de chaux. Afin d’extraire le sucre résiduel dans le gâteau de pressage obtenu, deux étapes de pressage supplémentaires avec une étape intermédiaire d’hydratation sont nécessaires. Ce procédé optimisé permet de bien épuiser les cossettes en sucre (perte en sucre de 0,23 % et matière sèche de pulpes de 39 %) pendant une courte durée d’extraction (30 min) avec un faible soutirage (108 %) par rapport au procédé de diffusion. Il permet ainsi des économies significatives de matière et d’énergie surtout pour les étapes d’extraction du jus et de séchage de pulpes. Par rapport au procédé conventionnel, le gain énergétique s’élève à 91,96 × 106 kWh pour une usine traitant 10 000 t/j de betteraves pendant une campagne de 110 jours. De plus, le procédé proposé permet de simplifier la procédure de purification et de réduire de 50 à 60 % la quantité de chaux utilisée. Dans la deuxième partie de cette étude, deux procédés de transformation ont été proposés et optimisés à l’échelle laboratoire pour la valorisation des radicelles et de la pulpe de betterave à sucre. Les radicelles ont été utilisées pour produire du bioéthanol. Le jus brut de radicelles a été extrait par pressage à froid assisté par CEP. La production du bioéthanol a été achevée par fermentation alcoolique. Le prétraitement par CEP (450 V/cm, 10 ms) a permis d’accélérer la cinétique de pressage, d’augmenter le rendement en solutés (79,85 % vs. 16,8 %) et d’obtenir un jus plus concentré (10 % vs. 5,2 %). Le procédé optimisé permet de produire environ 41,75 L de bioéthanol par tonne de radicelles lorsque l’on applique un prétraitement par CEP contre seulement 8,2 L de bioéthanol sans prétraitement électrique confirmant ainsi le potentiel de ce nouveau schéma de valorisation. La pulpe de betterave déshydratée ayant une matière sèche de 92,8 % a été utilisée pour l’extraction de pectines. L’étude réalisée a montré que l’application d’un prétraitement par DEHT permet d’intensifier l’extraction des pectines. Le gain relatif de rendement en pectines est de 25,3 % pour une énergie consommée de 76,2 kJ/kg. Le schéma de bioraffinage proposé pourra aider au maintien de la filière betteravière en France après la suppression de système de quotas sucriers dans l’Union européen qui entrera en vigueur le 1er octobre 2017. / This work discusses the use of electrotechnologies for an optimized valorization of sugar beet according to the concept of biorefinery. The applied electrotechnologies are pulsed electric fields (PEF) and high-voltage electrical discharges (HVED). The study firstly aims at optimizing an alternative method for sugar extraction by PEF assisted cold alkaline pressing. On the other hand, it proposes new ways for valorizing two by-products of sugar beet industry, which are sugar beet tails and pulps. In the first part, PEF treatment combined with liming leads to a better disintegration of beet tissue. It permits accelerating of pressing kinetics, improvement of juice yield and quality, and reduction of subsequent purification procedure. A parametric optimization study identified the best application itinerary of the proposed extraction process. Fresh sugar beet cossettes are pretreated by PEF at 600 V/cm for 10 ms (Q = 2.7 Wh/kg). The electroporated cossettes are then pressed to extract 75% of intracellular juice. Compressed cossettes are subjected to an alkaline pressing with 10% lime milk. In order to extract the residual sucrose in the obtained press-cake, two additional steps of pressing with an intermediate hydration are required. This optimized process allows well exhausting the sugar cossettes (sugar loss of 0.23% and pulp dry matter of 39%) for a short extraction (30 min) and with low draft (108%) compared to diffusion method. Thus, it allows substantial saving in materials and energy especially for juice extraction and pulp drying. Compared to the conventional method, the energy saving amounted to 91.96 × 106 kWh for a sugar beet factory treating 10 000 tons per day for a campaign of 110 days. In addition, the proposed method simplifies the purification procedure of raw juice and reduces the used amount of lime from 50 to 60%. In the second part of this study, two processing methods were proposed and optimized at lab-scale for valorization of sugar beet tails and pulps. Sugar beet tails were used to produce bioethanol. Raw juice of beet tails was extracted by PEF assisted cold pressing. Bioethanol production was then done by alcoholic fermentation. Pretreatment of beet tails with PEF (450 V/cm, 10 ms) permits accelerating the pressing kinetics, increasing the yield of solutes (79.85% vs. 16.8%), and leads to a more concentrated juice (10% vs. 5.2%). The optimized process permits the production of about 41.75 L of bioethanol per ton of beet tails when PEF pretreatment is applied against only 8.2 L of bioethanol without PEF confirming the potential of this new valorization scheme. Dried beet pulp having a dry matter of 92.8% was used for pectin recovery. The present study showed that the application of HVED pretreatment leads to intensify pectin extraction. The relative gain of pectin yield is 25.3% with an energy consumption of 76.2 kJ/kg. The proposed biorefinery scheme could protect the sugar beet industry in France after the suppression of the sugar quota system in the European Union, which will take effect on 1st October 2017.
210

Cytosine Methylation of an Ancient Satellite Family in the Wild Beet Beta procumbens

Schmidt, Martin, Hense, Sarah, Minoche, André E., Dohm, Juliane C., Himmelbauer, Heinz, Schmidt, Thomas, Zakrzewski, Falk 20 May 2020 (has links)
DNA methylation is an essential epigenetic feature for the regulation and maintenance of heterochromatin. Satellite DNA is a repetitive sequence component that often occurs in large arrays in heterochromatin of subtelomeric, intercalary and centromeric regions. Knowledge about the methylation status of satellite DNA is important for understanding the role of repetitive DNA in heterochromatization. In this study, we investigated the cytosine methylation of the ancient satellite family pEV in the wild beet Beta procumbens. The pEV satellite is widespread in species-specific pEV subfamilies in the genus Beta and most likely originated before the radiation of the Betoideae and Chenopodioideae. In B. procumbens , the pEV subfamily occurs abundantly and spans intercalary and centromeric regions. To uncover its cytosine methylation, we performed chromosome-wide immunostaining and bisulfite sequencing of pEV satellite repeats. We found that CG and CHG sites are highly methylated while CHH sites show only low levels of methylation. As a consequence of the low frequency of CG and CHG sites and the preferential occurrence of most cytosines in the CHH motif in pEV monomers, this satellite family displays only low levels of total cytosine methylation.

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