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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

Charakterisierung pflanzlicher in vitro Kulturen am Beispiel Sonnenblume

Geipel, Katja, Bley, Thomas, Steingroewer, Juliane 22 February 2017 (has links) (PDF)
Wirkstoffgewinnung mittels chemischer Synthese führt oft zu Stereoisomeren, welche aufwendig getrennt werden müssen und manche Moleküle sind nur sehr kostenintensiv oder gar nicht darstellbar. Landwirtschaftliche Gewinnung bedeutet Nachteile wie Schadstoffeinsatz und großer Flächenbedarf. Der Einsatz von pflanzlichen Zell- und Gewebekulturen überwindet die genannten Hürden [1, 2]: mit Methoden der Pflanzenbiotechnologie ist es möglich, pflanzliche Inhaltsstoffe in ihrer natürlichen, bioaktiven Form das ganze Jahr über unabhängig von biotischen/abiotischen Umweltfaktoren bei gleichbleibender Qualität und Quantität zu produzieren [3, 4]. Suspensionskulturen und hairy roots gelten momentan als die in vitro-Kulturtypen mit dem größten biotechnologischen Potential. Erstere sind in Flüssigmedium kultivierte Kalluszellen. Bei Kallus handelt es sich um undifferenzierte Pflanzenzellen, welche tumorartig wachsen und durch Zugabe von Pflanzenhormonen an der Differenzierung gehindert werden. Hairy roots entstehen durch Infektion eines Pflanzenteils mit dem Bodenbakterium Agrobacterium rhizogenes. Die so erhaltene Haarwurzelkultur kann ohne Hormonzusatz vermehrt werden, ihre Morphologie erfordert aber häufig eine Anpassung bestehender Kultivierungsgefäße [2, 5]. / In advance of industrial applications of in vitro plant cell or tissue cultures e.g., as bioactive ingredients for pharmaceuticals, an intense characterization concerning growth and productivity has to be performed. Innovative respiration measurement techniques in shake flask scale were applied to investigate and compare heterotrophic, photomixotrophic and hairy root cultures of sunflower. Furthermore, the qualification of RAMOS for screening of plant in vitro cultures is discussed.
2

Charakterisierung pflanzlicher in vitro Kulturen am Beispiel Sonnenblume

Geipel, Katja, Bley, Thomas, Steingroewer, Juliane January 2014 (has links)
Wirkstoffgewinnung mittels chemischer Synthese führt oft zu Stereoisomeren, welche aufwendig getrennt werden müssen und manche Moleküle sind nur sehr kostenintensiv oder gar nicht darstellbar. Landwirtschaftliche Gewinnung bedeutet Nachteile wie Schadstoffeinsatz und großer Flächenbedarf. Der Einsatz von pflanzlichen Zell- und Gewebekulturen überwindet die genannten Hürden [1, 2]: mit Methoden der Pflanzenbiotechnologie ist es möglich, pflanzliche Inhaltsstoffe in ihrer natürlichen, bioaktiven Form das ganze Jahr über unabhängig von biotischen/abiotischen Umweltfaktoren bei gleichbleibender Qualität und Quantität zu produzieren [3, 4]. Suspensionskulturen und hairy roots gelten momentan als die in vitro-Kulturtypen mit dem größten biotechnologischen Potential. Erstere sind in Flüssigmedium kultivierte Kalluszellen. Bei Kallus handelt es sich um undifferenzierte Pflanzenzellen, welche tumorartig wachsen und durch Zugabe von Pflanzenhormonen an der Differenzierung gehindert werden. Hairy roots entstehen durch Infektion eines Pflanzenteils mit dem Bodenbakterium Agrobacterium rhizogenes. Die so erhaltene Haarwurzelkultur kann ohne Hormonzusatz vermehrt werden, ihre Morphologie erfordert aber häufig eine Anpassung bestehender Kultivierungsgefäße [2, 5]. / In advance of industrial applications of in vitro plant cell or tissue cultures e.g., as bioactive ingredients for pharmaceuticals, an intense characterization concerning growth and productivity has to be performed. Innovative respiration measurement techniques in shake flask scale were applied to investigate and compare heterotrophic, photomixotrophic and hairy root cultures of sunflower. Furthermore, the qualification of RAMOS for screening of plant in vitro cultures is discussed.
3

Salvia suspension cultures as production systems for oleanolic and ursolic acid

Haas, Christiane, Hengelhaupt, Karl-Christoph, Kümmritz, Sibylle, Bley, Thomas, Pavlov, Atanas, Steingroewer, Juliane 26 January 2017 (has links) (PDF)
Oleanolic and ursolic acid (OA and UA) are triterpenic acids with diverse biological activities that are of interest to the pharmaceutical industry. To investigate the scope for producing these compound using cell suspension cultures of Salvia species, calli from S. officinalis, S. virgata and S. fruticosa were induced using several plant growth regulator (PGR) combinations. Eleven lines were selected for suspension induction from a pool of calli. Six suspension cultures were established successfully and cultivated in the Respiration Activity MOnitoring System® (RAMOS®) to obtain online data on their growth kinetics and to establish appropriate sampling schedules for the determination of their OA and UA production. Based on their observed growth behaviour, OA and UA contents, and aggregation properties, one suspension culture from each studied Salvia species was selected for further optimisation. The μmax values for these suspension cultures ranged from 0.20 to 0.37°d-1, their OA and UA contents were greater than 1.3 and 1.2 mg g-1, respectively, and they afforded maximum volumetric yields of 21.0 mg l-1 for OA and 32.8 mg l-1 for UA. These results will be useful in the development of a refined Salvia suspension-based process for OA and UA production.
4

Growth kinetics of a Helianthus annuus and a Salvia fruticosa suspension cell line: Shake flask cultivations with online monitoring system

Geipel, Katja, Socher, Maria Lisa, Haas, Christiane, Bley, Thomas, Steingroewer, Juliane 15 November 2016 (has links) (PDF)
Plants produce a variety of secondary metabolites, e.g. to defend themselves against herbivores or to attract pollinating insects. Plant cell biotechnology offers excellent opportunities in order to use such secondary plant metabolites to produce goods with consistent quality and quantity throughout the year, and therefore to act independently from biotic and abiotic environmental factors. This article presents results of an extensive study of plant cell in vitro cultivation in a modern shake flask system with non-invasive online respiration activity monitoring unit. Comprehensive screening experiments confirm the successful transfer of a model culture (sunflower suspension) into the shake flask monitoring device and the suitability of this respiration activity monitoring unit as qualified tool for screening of plant in vitro cultures (sunflower and sage suspension). The authors demonstrate deviations between online and offline data due to varying water evaporation from different culture flask types. The influence of evaporation on growth-specific parameters thereby rises with increasing cultivation time. Furthermore, possibilities to minimize the impact of evaporation, either by adjusting the inlet air moisture or by measuring the evaporation in combination with an appropriate correction of the measured growth values, are shown.
5

Growth kinetics of a Helianthus annuus and a Salvia fruticosa suspension cell line: Shake flask cultivations with online monitoring system

Geipel, Katja, Socher, Maria Lisa, Haas, Christiane, Bley, Thomas, Steingroewer, Juliane 15 November 2016 (has links)
Plants produce a variety of secondary metabolites, e.g. to defend themselves against herbivores or to attract pollinating insects. Plant cell biotechnology offers excellent opportunities in order to use such secondary plant metabolites to produce goods with consistent quality and quantity throughout the year, and therefore to act independently from biotic and abiotic environmental factors. This article presents results of an extensive study of plant cell in vitro cultivation in a modern shake flask system with non-invasive online respiration activity monitoring unit. Comprehensive screening experiments confirm the successful transfer of a model culture (sunflower suspension) into the shake flask monitoring device and the suitability of this respiration activity monitoring unit as qualified tool for screening of plant in vitro cultures (sunflower and sage suspension). The authors demonstrate deviations between online and offline data due to varying water evaporation from different culture flask types. The influence of evaporation on growth-specific parameters thereby rises with increasing cultivation time. Furthermore, possibilities to minimize the impact of evaporation, either by adjusting the inlet air moisture or by measuring the evaporation in combination with an appropriate correction of the measured growth values, are shown.
6

Salvia suspension cultures as production systems for oleanolic and ursolic acid

Haas, Christiane, Hengelhaupt, Karl-Christoph, Kümmritz, Sibylle, Bley, Thomas, Pavlov, Atanas, Steingroewer, Juliane January 2014 (has links)
Oleanolic and ursolic acid (OA and UA) are triterpenic acids with diverse biological activities that are of interest to the pharmaceutical industry. To investigate the scope for producing these compound using cell suspension cultures of Salvia species, calli from S. officinalis, S. virgata and S. fruticosa were induced using several plant growth regulator (PGR) combinations. Eleven lines were selected for suspension induction from a pool of calli. Six suspension cultures were established successfully and cultivated in the Respiration Activity MOnitoring System® (RAMOS®) to obtain online data on their growth kinetics and to establish appropriate sampling schedules for the determination of their OA and UA production. Based on their observed growth behaviour, OA and UA contents, and aggregation properties, one suspension culture from each studied Salvia species was selected for further optimisation. The μmax values for these suspension cultures ranged from 0.20 to 0.37°d-1, their OA and UA contents were greater than 1.3 and 1.2 mg g-1, respectively, and they afforded maximum volumetric yields of 21.0 mg l-1 for OA and 32.8 mg l-1 for UA. These results will be useful in the development of a refined Salvia suspension-based process for OA and UA production.

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