Accumulation of biologically active furanocoumarins in Ruta graveolens ssp. divaricata (Tenore) Gams in vitro culture.

The study was designed to investigate dynamics of accumulation of five linear furanocoumarins and umbelliferone in stationary liquid cultures of Ruta graveolens ssp. divaricata (Tenore) Gams during 6-week growth cycles. The contents of individual metabolites in biomass increased 1.8-3.5 times while their total content rose 2.3 times. Maximum contents of xanthotoxin, bergapten and isopimpinellin (112.3, 76.2 and 84.0mg/100g d.w., respectively) and maximum total content of all metabolites (283.4 mg/100 g d.w.), obtained on 35th culture day, are interesting from practical point of view.

Identification of benzodiazepines in Artemisia dracunculus and Solanum tuberosum rationalizing their endogenous formation in plant tissue.

Sterile cultivated plant cell tissues and cell regenerates of several species were tested for their binding affinity to the central human benzodiazepine receptor. Binding activity was found in extracts of Artemisia dracunculus cell tissue (IC(50) = 7 microg/ml) and, to a lesser extent, in plant regenerates of potato herb (Solanum tuberosum). Preparative HPLC led to the isolation of fractions with a significant displacing potency in the benzodiazepine receptor binding assay. Using on-line HPLC-electrospray-tandem mass spectrometry (HPLC-ESI-MS/MS) in the "selected reaction monitoring" (SRM) mode, delorazepam and temazepam were found in amounts of about 100 to 200 ng/g cell tissue of Artemisia dracunculus, whereas sterile potato herb contained temazepam and diazepam ranging approximately from 70 to 450 ng/g cell tissue. It is the first report on the endogenous formation of benzodiazepines by plant cells, as any interaction of microorganisms and environmental factors was excluded.

Tissue culture of the desert plant Anastatica hiërochuntica.

Callus derived from the winter annual desert plant Anastatica hiërochuntica was grown on different media, Murashige and Skoog (1962) medium giving the best results. Large amounts of lignified xylem elements were formed resulting in an extremely hard tissue. The growth responses to different auxins, cytokinins and abscisic acid were investigated. When salts (high Na(+), Ca(2+) and Cl(-)-contents) as they can be found in aqueous extracts of desert soils from a natural A. hiëerochuntica habitat were added to Abou-Mandour (1977) or MS-media, growth of callus was inhibited drastically. In the presence of abscisic acid, however, original growth was completely restored. In salt free control media on the other hand, ABA proved to be inhibitory. Drought stress caused a decrease of both cytokinins and indoleacetic acid in the callus while ABA levels were increased, but by far not as distinct as in intact plants. Proline level was not affected by stress.

The influence of phytohormones on growth, organ differentiation and fructan production in callus of Symphytum officinale L.

Callus derived from Symphytum officinale L. regenerants was cultured in the presence of various phytohormones. The growth rate of callus was stimulated by all phytohormones at various concentrations. With 1-naphthaleneacetic acid no organ differentiation could be observed. With indole-3-butyric acid at low concentrations only roots were formed, whereas 6-benzylaminopurine, kinetin and zeatin at various concentrations induced either root or shoot formation or the simultaneous regeneration of both. Minor amounts of fructans were formed at high 6-benzylaminopurine-, zeatin- and at all indole-3-acetic acid-concentrations. The concentration of 1-naphthaleneacetic acid had no influence on the fructan content. Highest rates of fructan synthesis occurred at low zeatin-concentrations up to 1.5 mg/l. Only zeatin at all concentrations induced the synthesis of polyfructans, whereas appreciable amounts of oligofructans were formed under the influence of all other phytohormones.

Fructan Synthesis in Tissue Cultures of Symphytum officinale; L. Initiation, Differentiation, and Metabolic Activity.

Tissue cultures originating from different organs i.e. leaves, leaf-stalks, ovaries, anthers, and roots of SYMPHYTUM OFFICINALE were initiated under various growth conditions and subcultured several times to give the first callus generation. From all these calli, whole plants could be regenerated which again were used for the preparation of tissue cultures resulting in the formation of the second callus generation. The different calli and the regenerated plants were analyzed with respect to the fructan-synthesizing capacity. Only calli derived from the leaves of the original plant synthesized fructan whereas calli derived from ovaries, anthers, and roots, which are known to contain large amounts of fructan, were not capable of synthesizing fructan. The regenerated plants obtained from the first callus generation showed ability for fructan synthesis only if the originating callus synthesized fructan. The calli of the second generation, which were prepared from fructan-containing leaves and roots of regenerated plants, showed the capacity for fructan formation. The calli of the second generation obtained from leaves and roots of regenerated, fructan-free plants were not able to synthesize this specific reserve polysaccharide. From these data it can be concluded that the calli of the first generation prepared from roots, ovaries, and anthers have lost their ability for fructan synthesis. Calli initiated from leaves and leaf-stalks preserved the capacity for fructan formation even after many calli generations and regeneration to entire plants. Different phytohormones used in the tissue cultures had only a slight effect upon the fructan formation. An influence of light on fructan synthesis could not be detected.

[Studies on Ruta graveolens ssp. divaricata]. / Untersuchungen an Ruta graveolens ssp. divaricata.

Parts of leaves, stems and roots of Ruta graveolens ssp. divaricata (Tenore) Gams were explanted on Linsmaier and Skoog (16) medium. All explants showed good callus growth under various culture conditions. With stem derived tissue cultures, the capability for differentiation and regeneration was examined in response to variations of media and phytohormonal composition. In darkness, cultures produced roots of various length depending on composition of the media. Under continuous illumination (1200 lux) cultures produced fully green shoot regenerates on various media though complete plants could not be regenerated.

[Investigations on harpagophytum.]. / Untersuchungen der Gattung Harpagophytum.

Comparing the analytical results of the constituants of naturally growing roots and callus of Harpagophytum procumbens, it could be demonstrated that both, the products of the primary and the secondary metabolism, showed important differences. Harpagosid which is present in significant amounts in the roots and tubers of the fresh plants, was shown to be completely absent in the callus. Stachyose the main reserve carbohydrate again was only produced in minor amounts. Fructose was the predominant sugar in the callus cells.

[On the existence of a cytokinin-like factor in cuscuta reflexa]. / Über das Vorkommen eines cytokininartigen Faktors inCuscuta reflexa.

In extracts ofCuscuta reflexa ROXB. a cytokinin like factor (CAF = Cuscuta active factor) was found. It was shown that activity of this factor is similar to that of kinetin in all essential points. In tobacco-stem-tissue tests a promotion of growth by CAF was observed. In chlorophyll-preservation tests CAF produced a strong inhibition of chlorophyll dissimilation. Moreover in tests with(14)C-labelled glycine a migration of the glycine and other amino acids due to CAF was found.The occurrence of the observed cytokinin-like factor inCuscuta reflexa is discussed with respect to the parasite-host relations ofCuscuta.