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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.
1

Transformed root cultures for production of secondary metabolites

Marzouk, Amani M. January 2002 (has links)
No description available.
2

RNAi-Untersuchungen und Überexpression von Genen der Rosmarinsäurebiosynthese

Hücherig, Stephanie. Unknown Date (has links)
Univ., Diss., 2010--Marburg.
3

Effet de l'environnement sur la croissance et l'accumulation de métabolites secondaires chez Datura innoxia Mill. cultivé en conditions hors sol ; impact des facteurs biotiques et abiotiques

Vu, Thi Dao Gontier, Eric Bourgaud, Frédéric January 2008 (has links) (PDF)
Thèse de doctorat : Sciences agronomiques : INPL : 2008. / Titre provenant de l'écran-titre.
4

Genetic transformation of Ceratotheca triloba for the production of anthraquinones from hairy root cultures

Naicker, Leeann January 2012 (has links)
Submitted in complete fulfillment for the Degree of Master of Technology: Biotechnology, Durban University of Technology, 2012. / Many secondary metabolites that have been extracted from medicinal plants have been used as source of clinical drugs. However, the concentration of the active metabolites in plants is generally low. An attractive alternative for producing these important secondary metabolites is via plant tissue culture technology. More particularly, the genetic transformation of a plant tissue by Agrobaterium rhizogenes has been employed for producing high yields of secondary metabolites. In a previous study, three structurally similar anthraquinones: 9,10-Anthracenedione, 1-Hydroxy-4-methylanthraquinone and 5,8-Dimethoxy-2,3,10,10a-tetrahydro-1H,4aH-phenanthrene-4,9-dione, and one steroid; Androst-5-ene-3, 17, 19-triol were isolated from the root extracts of C. triloba. The anthraquinones have shown to exhibit the anticancer mechanism which involves the inhibition of the activity of the human topoisomerase II enzyme that transforms supercoiled DNA to linear DNA. However, these anthraquinones were found in very low concentrations. Therefore, in this study we used plant cell and tissue culture systems (cell suspension, shoot and hairy root cultures) of C. triloba to increase the production of anthraquinones. Since the establishment of C. triloba in vitro plant systems required a source sterile explants, a protocol that involved the use of NaCIO was optimized for the sterilization and subsequent germination of C. triloba seeds which were micro-propagated into shoot cultures. These cultures provided a source explants for the induction of callus and hairy root cultures. The biomass of these plant cell and tissue cultures were subsequently bulked up for the extraction for anthraquinones and the yields were compared followed by fractionation and identification of the major compounds. The bioactivity of the fractions was evaluated by testing their cytotoxicity on cancer cells and anti-topoisomerase activity. The sterilization protocol that provided sterile seeds was found to be a solution of 30% NaCIO at an exposure time of 10 minutes. From the sterilized seeds shoot cultures were established on MS medium. The leaf explants of the shoot cultures were then used to induce callus cultures which subsequently were transferred to liquid medium whereby the total biomass of suspension cultures increased from 4 g to 134.18 g (wet weight). Also hairy roots cultures were established from stem explants with a low cell density inoculum of A. rhizogenes at a transformation efficiency of 73%. The growth of these hairy roots was slow in hormone free medium. This was overcomed with the use NAA and IAA which increased the xvii biomass from 1.03 g in the control culture (without hormone) to 23.91 g and 46.13 g respectively. An evaluation of the anthraquinones in the field root and hairy root, cell suspension and shoot culture extracts was carried out by using their Thin Layer Chromatography profiles and the High Performance Liquid Chromatography profiles as well as the standards, 9,10-Anthracenedione and 1-Hydroxy-4-methylanthaquinone. TLC analysis showed that the RF values of the fractions CT01 and CT02 matched the RF values of anthraquinones standards while HPLC analysis revealed that hairy root cultures supplemented with IAA (125.03 μg.mg-1) or NAA (98.25 μg. mg-1) produced a higher concentration of anthraquinones than the control culture (without hormone) (13.33 μg.mg-1), the field roots (33.51 μg. mg-1) and the shoot (3.23 μg.mg-1) and cell suspension cultures (13.17 μg.mg-1). Due to co-elution of the compounds in HPLC analysis, six fractions were isolated by Preparative Thin Layer Chromatography from the hairy root extract (obtained from the culture supplemented with NAA) and were coded as CT01, CT02, CT03, CT04, CT05 and CT06. The compounds in these fractions were identified by Electron Ionization-Liquid chromatography-Mass Spectroscopy and it was found that the hairy roots produced one acridone derivative; 5-Methoxy-2-nitro-10H-acridin-9-one, one naphthoquinone derivative; 2H-Naphto[2,3-b]pyran-5,10-dione,3,4-dihydro-2,2-dimethyl- and seven anthracenedione derivatives. These were: i) 5,8-Dimethoxy-2,3,10,10a-tetrahydro-1H,4aH-phenanthrene-4,9-dione, ii) 9,10-Anthracenedione, 2-methyl-, iii) 1-Hydroxy-4-methylanthraquinone, iv) 9,10-Anthracenedione, 2-ethyl-, v) 1,5-Diaminoanthraquinone, vi) Phenanthrene, 3,6-dimethoxy-9-methyl-, vii) 9,10-Anthracenedione, 1,4-dimethyl-. Fractions CT01 (5,8-Dimethoxy-2,3,10,10a-tetrahydro-1H,4aH-phenanthrene-4,9-dione, 9,10-Anthracenedione, 2-methyl- and 1-Hydroxy-4-methylanthraquinone) and CT02 (9,10- Anthracenedione, 2-ethyl-) were cytotoxic to the DU-145 cancer cell line at concentrations of 125 μg.mg-1 to 1000 μg.mg-1. These fractions also showed anti-topoisomerase activity as they inhibited the conversion of supercoiled DNA into linear DNA. In conclusion this is the first study that describes the transformation of C. triloba by A. rhizogenes mediated transformation and compares the production of anthraquinones in C. triloba hairy roots to the field roots, shoot and cell suspension cultures. This study has xviii indicated that hairy root cultures is a high-yielding production system for anthraquinones (5,8-Dimethoxy-2,3,10,10a-tetrahydro-1H,4aH-phenanthrene-4,9-dione, 1-Hydroxy-4-methylanthraquinone, 9,10-Anthracenedione, 2-methyl- and 9,10- Anthracenedione, 2-ethyl-) which could have the potential to be used in cancer therapy. In addition the discovery of C. triloba hairy roots having the biosynthetic capacity to synthesize five valuable anthraquinone derivatives that are not found the field roots has also been revealed.
5

Studies of adventitious root formation in woody species /

Sedira, Monika, January 2006 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
6

Untersuchungen an Datura stramonium Hairy-root-Wurzelkulturen im Hinblick auf das Enzym Littorinmutase /

Morlock, Gaby. January 2002 (has links)
Universiẗat, Diss--Karlsruhe, 2002.
7

Studies on the biochemistry of the hairy-root and crown-gall organisms

Conner, Hubert Andrew. January 1935 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1935. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 34-37).
8

Micropropagação e protocolo para transformação de mandioca (Manihot esculenta Crantz) via Agrobacterium rhizogenes / Micropropagation and the protocol for cassava transformation (Manihot esculenta Crantz) by means of Agrobacterium rhizogenes

Sato, Aurora Yoshiko 15 December 1999 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-04-24T12:12:21Z No. of bitstreams: 1 texto completo.pdf: 1281900 bytes, checksum: 4472f78480864646e3d483fe0dffb30a (MD5) / Made available in DSpace on 2017-04-24T12:12:21Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1281900 bytes, checksum: 4472f78480864646e3d483fe0dffb30a (MD5) Previous issue date: 1999-12-15 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Foram realizados dois trabalhos no laboratório de testes de progênie do Departamento de Fitotecnia da Universidade Federal de Viçosa, em Viçosa-MG. Um com a finalidade de desenvolver um protocolo de transformação de plantas de mandioca (Manihot esculenta Crantz) via Agrobacterium rhizogenes resistente à canamicina, e o outro para avaliar o efeito de fotoperíodo, filtros coloridos, nitrato de amônio, 2,4-D, picloram, ABA, AgNO 3 e STS na micropropagação de plântulas de mandioca. Na transformação da mandioca foram testados: a) meio seletivo com canamicina (0,0; 100; 200; 300; 400; 500; 600; 700; 800; 900; e 1.000 mg/L), b) influência da idade e luz nos discos foliares co-cultivados com a bactéria, c) efeito do ANA (0,0; 0,1; 1,0; 2,0; 3,0; 4,0; e 5,0 mg/L) no co- cultivo, d) efeito de concentrações de BAP (1,0; 10,0; 50; e 100,0 mg/L), e) efeito do GA 3 (0,05) + BAP (2,0 mg/L) e picloram (8,0 mg/L). Foi também realizada a análise isozimática do material. Avaliaram-se: peso da matéria seca, número de folhas e raízes, comprimento da parte aérea, presença de injúrias e coloração de folhas e caule. A partir de 100 mg/L de canamicina, as plântulas apresentaram fitotoxidez; folhas novas e no claro apresentam os melhores resultados; o melhor resultado com ANA foi obtido a 2,0 mg/L; calos transformados apresentaram maior peso de matéria seca com 10 mg/L de BAP e com picloram; na análise isozimática constatou-se diferença no padrão de bandas. Na micropropagação, avaliaram-se as mesmas características dos experimentos de transformação; nos experimentos com STS e AgNO 3 foram avaliados também o teor de clorofila, e nos de nitrato de amônio, fotoperíodo, filtros coloridos e ABA foi feita também uma análise mineral do material vegetal. Avaliou-se o efeito do nitrato de amônio (0; 1/8; 1/4; 1/2; 3/4; 1; e 2 da concentração original) com e sem BAP. Estudou-se o efeito dos fotoperíodos: 0; 8 e 16 h luz. Quanto ao efeito do STS e AgNO 3, as concentrações utilizadas foram: de STS (0, 20, 30 e 50 μM) e de AgNO 3 (0, 10, 30 e 50 μM). Foram avaliados os efeitos de 2,4-D (0; 4,4; e 8,8 mg/L) e picloram (0; 4,8; e 9,6 mg/L) no claro e no escuro. Verificou-se também o efeito de 2,4-D (0; 2,2; 4,4; 6,6; e 8,8 mg/L) e ABA (0,0; 1,0 e 10 mg/L). Para avaliar o efeito da qualidade de luz, as plântulas foram colocadas sob filtros de acrílico vermelho, amarelo e azul. Os resultados obtidos indicaram que, com ou sem o BAP, pode-se usar uma concentração de nitrato de amônio abaixo da normalmente utilizada; o 2,4-D teve efeito melhor na concentração de 4,4 mg/L no escuro; e o picloram não induziu nenhum tipo de mudança morfogênica. O ABA impediu o crescimento da mandioca. O filtro amarelo foi o mais indicado para um estudo na área de enraizamento. O fotoperíodo age diferente conforme, o cultivar. Tanto para o AgNO 3 como para o STS a resposta da mandioca não foi benéfica. / There were two researches done in the progenie test laboratory at the Plant Technology Department at the Federal University of Viçosa, in Viçosa-MG. One of them had as its aim to develop a manioc plant transformation protocol (Manihot esculenta Crantz) by means of Agrobacterium rhizogenes which is resistant to kanamicine, and the other was to evaluate the effect of the photoperiod, colour filters, ammonium nitrate; 2,4-D, picloram, ABA, AgNO 3 and STS in the small plant of cassava. The following were tested during the cassava transformation: a) selective means with kanamicine (0,0; 100; 200; 300; 400; 500; 600; 700; 800; 900; and 1.000 mg/L), b) the influence of age and light over the leaf disks which were cultivated in bacteria, c) the effect of ANA (0,0; 0,1; 1,0; 2,0; 3,0; 4,0; and 5,0 mg/L) in the co-cultivate, d) the effect of the BAP (1,0; 10,0; 50; and 100,0 mg/L) concentrations, e) the effect of the GA3 (0,05) + BAP (2,0 mg/L) and picloram (8,0 mg/L). There was also a isozimatic analysis of the material. The following were evaluated: dry matter weight, the number of leaves and roots, the length of the aerial part, the presence of damage and the coloring of the leaves and stem. With 100 mg/L of kanamicine, the small plants presented phitotoxidity; the new leaves and under light present better results; the best result with ANA was obtained with 2,0 mg/L; the calluses that were formed presented heavier weight, 10 mg/L of BAP, within the dry matter and with picloram; there was a difference with the band pattern in the isozimatic analysis. The same characteristics of the transformation experiments were evaluated; the chlorophyll content was evaluated in the experiments that had STS and AgNO 3, and there was also a mineral analysis of the vegetal material done for the photoperiod, colored filters and ABA. The effect of the ammonium nitrate (0; 1/8; 1/4; 1/2; 3/4; 1; and 2 from the original concentration) with and without BAP was evaluated. The effects of the photoperiods of light were studied : 0; 8 and 16 light hours. For the effect of the STS and the AgNO 3, the concentrations that were used were: STS (0, 20, 30 e 50 μM) and AgNO 3 (0, 10, 30 and 50 μM). The effects of the 2,4-D (0; 4,4; and 8,8 mg/L) and picloram (0; 4,8; and 9,6 mg/L) in the light and in the dark were evaluated. The effect of 2,4-D (0; 2,2; 4,4; 6,6; and 8,8 mg/L) and ABA (0,0; 1,0 and 10 mg/L) was verified. To evaluate the light quality effect, the small plants were put under red, yellow and blue acrylic filter. The results that were obtained indicated that, with or without BAP, a ammonium nitrate concentration can be used below the usual amount that is used; the 2,4-D had a better effect in the concentration of 4,4 mg/L in the dark; and the picloram did not induce any type of morphogenic change. The ABA inhibited the growth of the manioc. The yellow filer was more indicated for a study in the rooting area. The photoperiod works differently according the cultivar. Either for the AgNO 3 or for the STS the return from the cassava was not beneficial.
9

IZOLACE TRANSGENNÍCH ROSTLIN NICOTIANA TABACUM A SILENE VULGARIS / ISOLATION OF TRANSGENIC PLANTS NICOTIANA TABACUM AND SILENE VULGARIS

Kováčová, Viera January 2010 (has links)
This project is focused on transformation of Silene vulgaris mediated by Agrobacterium tumefaciens and A. rhizogenes. S. vulgaris is a good model plant to study gynodioecy, an evolutionary step from bisexuality to dioecy. Gynodioecious plants form in some individuals bisexual flowers, while the others possess only female flowers. The aim of this research is do develop a technique to introduce foreign genes into this plant to study its developmental consequences. Using A. rhizogenes we successfuly prepared hairy root cultures, which unfortunately do not form shoot regenerants. We have prepared a protocol to induce plant regenerants from S. vulgaris leaf fragments. The first results do not confirm that A. tumefaciens infected plant regenerants harbor reporter transgenes. We used Nicotiana tabacum as a positive control.
10

Effet de l'environnement sur la croissance et l'accumulation de métabolites secondaires chez Datura innoxia Mill. cultivé en conditions hors sol ; impact des facteurs biotiques et abiotiques / Effects of biotic and abiotic environmental parameters for Datura innoxia Mill. tropane alkaloid in soilless cultures

Vu, Thi Dao 04 July 2008 (has links)
Datura innoxia Mill., une plante de la famille des Solanacées synthétisant des métabolites secondaires, dont les alcaloïdes tropaniques, a été utilisée comme modèle pour cette étude portant sur les cultures en hydroponie. Nous avons déterminé et hiérarchisé les paramètres environnementaux (biotiques et abiotiques) permettant d’améliorer croissance et production de métabolites. La réponse de la plante dépend de l’approvisionnement en oxygène de la solution nutritive, de la température perçue tant niveau des parties aériennes qu’au niveau racinaire. Une augmentation de l’intensité d’éclairage n’améliore pas la teneur en alcaloïdes de la plante mais l’utilisation de lumière orange engendre un changement des paramètres de croissance et des teneurs en molécules recherchées. Nous avons également montré que la présence de microflore dans le milieu de culture provoque une dégradation des molécules d’intérêt et altère leur accumulation dans la plante. Par contre, A. rhizogenes a un effet favorable sur la croissance de la biomasse et la biosynthèse d’alcaloïdes tropaniques dans la plante. L’état transgénique des racines, issues de co-culture hydroponique de Datura innoxia avec A. rhizogenes TR7, a été estimé par une vérification précoce et confirmé par des analyses moléculaires. Nous avons pu mettre en évidence les modifications du phénotype racinaire et les mécanismes d'interaction plante-microorganisme. L’inoculation des agrobactéries peut donner lieu à des transferts naturels de gènes induisant ainsi l’obtention d’un pool racinaire chimérique regroupant des racines normales et des racines transformées. Ces travaux ont ouvert de nouvelles perspectives en vue de déterminer la capacité de production de métabolites secondaires par des plantes en culture hors sol, de manière à obtenir une biomasse riche en molécules recherchées / Datura innoxia Mill. a plant species belonging to Solanaceous family, produces hyoscyamine and scopolamine as two main tropane alkaloids. It has been studied in the present work for the development of hydroponic based secondary metabolites bioproduction. More specifically, biotic and abiotic environmental factors have been analysed in order to improve growth and alkaloid accumulation in plant tissues. Oxygen concentration in the nutrient solution is proved to be important for both biomass and compound production in temporary immersion culture conditions occur as one optimum. Temperature has also a major effect, directly and most probably through oxygen solubility and root needs. We showed that artificial light may positively complete natural one but the kind of spectrum must be chosen carefully. From this point of view, orange light from High Pressure Natrium Vapour light showed better results than classical white light. Nitrogen (NO3-15mM) and pH (5 to 6) management may lead to culture optimization. We also show that well chosen wild Agrobacterium rhizogenes strains may be added to the hydroponic nutrient solution in order to improve growth and alkaloid bioproduction. This result is due to the multi occurrence of genetic transformation events. Our results lead to a first classification for impacts of biotic and abiotic factors. It opens new window for plant milking technology industrial development

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