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1.
Plants (Basel) ; 4(1): 44-62, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-27135317

RESUMEN

In the preparation for missions to Mars, basic knowledge of the mechanisms of growth and development of living plants under microgravity (micro-g) conditions is essential. Focus has centered on the g-effects on rigidity, including mechanisms of signal perception, transduction, and response in gravity resistance. These components of gravity resistance are linked to the evolution and acquisition of responses to various mechanical stresses. An overview is given both on the basic effect of hypergravity as well as of micro-g conditions in the cell wall changes. The review includes plant experiments in the US Space Shuttle and the effect of short space stays (8-14 days) on single cells (plant protoplasts). Regeneration of protoplasts is dependent on cortical microtubules to orient the nascent cellulose microfibrils in the cell wall. The space protoplast experiments demonstrated that the regeneration capacity of protoplasts was retarded. Two critical factors are the basis for longer space experiments: a. the effects of gravity on the molecular mechanisms for cell wall development, b. the availability of facilities and hardware for performing cell wall experiments in space and return of RNA/DNA back to the Earth. Linked to these aspects is a description of existing hardware functioning on the International Space Station.

2.
Nat Prod Res ; 19(8): 755-61, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16317830

RESUMEN

The hexane fraction from the roots of Echinops ellenbeckii O. Hoffm. from Ethiopia yielded seven acetylenic thiophenes of which five compounds (1, 3, 4, 6, 7) are reported for the first time in this species: the monothiophenes 5-(penta-1,3-diynyl)-2-(but-3-en-1-ynyl)-thiophene (1), 5-(penta-1,3-diynyl)-2-(4-acetoxy-but-1-ynyl)-thiophene (2), 5-(penta-1,3-diynyl)-2-(3-hydroxy-4-acetoxy-but-1-ynyl)-thiophene (3), 5-(penta-1,3-diynyl)-2-(3,4-diacetoxy-but-1-ynyl)-thiophene (4), 5-(penta-1,3-diynyl)-2-(3-chloro-4-acetoxy-but-1-ynyl)-thiophene (5), 5-(penta-1,3-diynyl)-2-(3,4-epoxy-but-1-ynyl)-thiophene (6) and the dithiophene 5-[(5-acetoxymethyl-2-thienyl)-2-(but-3-en-1-ynyl)]-thiophene (7). Additionally, four fatty acids (C14, C15, C16 and C18), seven fatty acid esters and three long-chain hydrocarbons could be identified. All the structures were elucidated on the basis of spectral data by GC-MS, HRMS and the NMR techniques.


Asunto(s)
Asteraceae/química , Raíces de Plantas/química , Tiofenos/aislamiento & purificación , Asteraceae/citología , Asteraceae/fisiología , Cromatografía de Gases , Etiopía , Ácidos Grasos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Raíces de Plantas/citología , Tiofenos/química , Tiofenos/metabolismo
3.
J Agric Food Chem ; 53(12): 4946-53, 2005 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15941340

RESUMEN

Tansy (Tanacetum vulgare L.) was cultivated at the Norwegian Crop Research Institute at the Apelsvoll Research Centre, Division Kise, in the period from 2000 to 2001. The study focused on different harvesting regimens for high biomass production and essential oil (EO) yield and quality. Two tansy genotypes from Canada (Richters and Goldsticks) and three Norwegian genotypes (Steinvikholmen, Alvdal, and Brumunddal) were studied. The Canadian genotypes reached a height of 130-145 cm and showed a higher dry weight of aerial plant parts compared to the Norwegian plants in 2000. Similar oil yields could be observed for the Canadian types and genotype Steinvikholmen in the range of 30.8-34.6 L/ha when the plants were harvested twice during budding and before flowering after regrowth (year 2001). In contrast, single harvesting at the full bloom stage resulted in higher oil yields, between 42.1 and 44.5 L/ha (Canadian genotypes), whereas 21.0-38.4 L/ha was obtained from the Norwegian types. Tansy genotypes could be grouped into the following chemotypes: the mixed chemotypes Steinvikholmen (thujone-camphor), Alvdal (thujone-camphor-borneol), Goldsticks (thujone-camphor-chrysanthenyl type), and Brumunddal (thujone-camphor-1,8-cineole-bornyl acetate/borneol-alpha-terpineol) and the distinct chemotype Richters, with average concentrations of (E)-chrysanthenyl acetate >40% in both leaf and flower EO.


Asunto(s)
Aceites Volátiles/metabolismo , Tanacetum/crecimiento & desarrollo , Tanacetum/metabolismo , Canadá , Flores/química , Flores/crecimiento & desarrollo , Cromatografía de Gases y Espectrometría de Masas , Genotipo , Noruega , Aceites Volátiles/análisis , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Tallos de la Planta/química , Tallos de la Planta/crecimiento & desarrollo , Estaciones del Año , Tanacetum/genética
4.
J Agric Food Chem ; 53(10): 4143-8, 2005 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-15884852

RESUMEN

In the period from 2000 to 2002, studies on peppermint (Mentha x piperita) herb and essential oil (EO) production have been conducted at Planteforsk, Apelsvoll Research Centre Div. Kise in Norway. The trials were aimed at finding the optimal harvest date and suitable drying methods to maximize EO yield and to obtain a desirable oil quality. Peppermint plants from the first production year (2000 and 2001) and the second production year (2002) were harvested during flowering at three developmental stages (early, full, and late bloom). Biomass and leaf production were recorded, and the water content of the plant material was detected after the application of different drying methods: instantaneous drying at 30, 50, and 70 degrees C and prewilting (ground drying) for 1 or 5 days followed by final drying at 30 degrees C. Finally, plant samples were transferred to The Plant Biocentre at NTNU, Trondheim, Norway, for hydrodistillation and gas chromatography-mass spectrometry (GC-MS) analyses of the EOs. Peppermint oil yield increased from early to full bloom and late bloom (average of all years and drying methods except for 50 and 70 degrees C: 2.95, 4.13 and 4.20 L/daa, respectively) as an effect of biomass production and leaf growth. The flavor-impact compounds, menthol and menthone, reached their optimum at full bloom (43-54 and 12-30%, respectively). Prewilting led to slight decreased EO levels after 1 day (7.7%) and 5 days of ground drying (1.5%) and no EO quality changes, compared to direct drying at 30 degrees C. The plant weight (H2O content) was drastically decreased to the average under 80 and 45% in all years, thus reducing the energy supply and costs for the necessary final drying step.


Asunto(s)
Agricultura/métodos , Desecación/métodos , Mentha piperita/química , Mentha piperita/crecimiento & desarrollo , Hojas de la Planta/química , Aceites de Plantas/análisis , Mentol/análisis , Aceites Volátiles/análisis , Hojas de la Planta/crecimiento & desarrollo , Factores de Tiempo
5.
New Phytol ; 163(1): 99-110, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33873779

RESUMEN

• Polygalacturonase-inhibiting proteins (PGIPs) have been demonstrated to play a role in host defence in several plants. • The PGIP now cloned from strawberry (Fragaria × ananassa) showed a high degree of homology to other fruit PGIPs. The gene expression of strawberry PGIP was monitored in healthy leaves, flowers and fruit at different maturity stages. PGIP transcript levels were also analysed following fruit inoculation with the fungal pathogen Botrytis cinerea in strawberry cultivars displaying variation in susceptibility. • Healthy mature berries showed the highest constitutive PGIP gene expression levels compared with leaves, flowers and immature fruit, indicating that the gene is developmentally regulated. Among the cultivars studied ('Elsanta', 'Korona', 'Polka', 'Senga sengana', 'Tenira'), 'Polka' had the highest constitutive expression level of PGIP. After inoculation with B. cinerea, all five cultivars displayed a significant induction of PGIP gene expression, but the differences between them were not statistically significant. • The high induction of the PGIP gene after inoculation with B. cinerea indicates that PGIP has a role in defence of strawberry.

6.
J Gravit Physiol ; 9(1): P223-4, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15002557

RESUMEN

Under separate contracts with ESA (FUMO and ERM Study) and as a link in the development of the European Modular Cultivation System's (EMCS) functionality and biocompatibility, plant studies have been performed at The Plant Biocentre in Trondheim, Norway. The main goal was to test whether the breadboards containing the major components planned for use in the EMCS would be optimal for space experiments with plant material. The test plans and the experimental set-up for the verification of biocompatibility and biological functionality included the use of a few model plant species including cress (Lepidium sativum L.) and Arabidopsis thaliana. The plants were tested at different developmental levels of morphological and physiological complexity (illumination, life support, humidity control, water supply, observation, short- and long-term plant growth experiments and contamination prevention). Results from the tests show that the EMCS concept is useful for long duration plant growth on the ISS.

7.
J Gravit Physiol ; 9(1): P355-6, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15002612

RESUMEN

The experiments performed were initiated as a part of the post-flight investigations after the "PROTO" experiment performed on IML-1. The present experiments were performed with protoplasts prepared using the same standard isolation procedures as for the IML-1. The protoplasts were vibrated for 24 h with and without air bubbles in the protoplast cultivation bags and in the range of 1 to 20 Hz with 4 mm amplitude. The vibrations were found to have a negative effect on the viability of the protoplasts in bags without air bubbles and the vibration threshold seemed to lie around 20 Hz. Air bubbles are likely to cause cavitation-like conditions, thus increasing the mechanical strain on the free-floating protoplasts. During the 30 days microgravity mode on the ISS, mechanical vibrations would not be expected to have a significant influence on potential protoplast experiments. Experiments with durations overlapping the rendezvous and reboost mode may be exposed to critical vibration levels.

8.
J Gravit Physiol ; 9(1): P369-70, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15002618

RESUMEN

The European Modular Cultivation System (EMCS) is one of a wide range of laboratory modules under construction by ESA that will be placed on the International Space Station (ISS). In the present study the development and construction of an important component in the EMCS, the Plant Cultivation Container (PCC), is described. The PCC as a "flower pot" will automatically provide the plants with water and liquid nutrients as needed. The PCC is located inside the plant growth unit, the Experiment Container (EC), on the EMCS and interfaces with the EMCS. The essential parts of the PCC are a Peltier element, a micro valve, a monitoring RH sensor with an integrated platinum RTD temperature sensor, a RH sensor that detects air leaving the PCC and controls the peristaltic pump, a DC-DC board that provides correct current to the Peltier element, and a switch/connector board. The PCC is presently being tested out at ESTEC/ESA.

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