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  • Studies on the alkaloid production of genetically transformed and non-transformed cultures of Lobelia inflata L.
    65-71.
    Views:
    134

    The investigations of the growth and alkaloid production of cell suspension-, callus-, organized- and hairy root cultures from Lobelia inflata L. proved that these cultures are able to synthesize the characteristic piperidine alkaloids of the intact plant. Alkaloid precursor amino acids (Phe, Lys) and plant growth regulators affect not only the growth and differentiation of tissue cultures but also their secondary metabolism. The synthetic regulator Sz/I I combined with Phe increased the total alkaloid content considerably in callus- and organized cultures; regulator Sz/28 especially increased the lobeline content (in organized cultures in response to Lys, in callus tissues as a result of Phe application). With the aim of optimizing growth and alkaloid production of the genetically transformed hairy root cultures of Lobelia inflata L. we studied the effect of some growth regulators (NAA, IAA, kinetin) and precursor amino acids (Lys, Phe). The kinetin had inhibiting effect on the growth and lobeline production of the hairy roots. The IAA and NAA increased the biomass formation and lobeline production. The highest lobeline level was detected in tissues cultivated on hormone-free medium containing Phe.

     

  • Atropine and scopolamine in leaf and flower of Datura arborea L.
    61-64.
    Views:
    224

    Angel's trumpet (Danira = Brugmansia arhorea) is a common, popular ornamental plant in Hungary. On the basis of thin layer chromatographic and densitometric alkaloid studies of leaf and flower samples collected from several places in Somogy and Baranya counties it can be stated that in samples of cultivars with different flower colour, taken approximately at the same time, the atropine and scopolamine content varies: there are samples free of alkaloids, but most of them are rich in alkaloids. Although the means do not reflect the extremes, they are suitable for determining the alkaloid accumulating capacity of flowers. Generally the amount of atropine and scopolamine is significant both in the leaf and the flower. It is conspicuous that the flower can be characterised by an extremely high scopolamine content (mean in mg/g dry matter of leaf: atropine 0.34, scopolamine 0.31; of flower: atropine 0.26, scopolamine 0.85). Thus it can be stated that the leaf, and especially the flower of angel's trumpet is a potential hallucinogen, just like in the case of Datura stramonium.

  • Improved evaluation method for reliable distinction of poppy (Papaver somniferum L.) cultivars
    68-73.
    Views:
    164

    Investigating seven Hungarian standard cultivars (i.e. 'A1’, 'Kék Gemona', '13C-2`,'Kék Duna', `Kompolti M’, `Gödi N',

    'Kozmosz) it was proved that for the reliable distinction between cultivars a complex analysis is necessitated. Because of the large morpho­phenological and production-biological plasticity of the species qualitative and quantitative features as well as alkaloid accumulation characters have to be evaluated simultaneously applying discriminant analysis.

    It was proved by the investigations that some of the qualitative and quantitative characters included into the DUS evaluation procedure have slight importance for reliable distinction. As an example the majority of cultivars show high inhomogentity in such characters like the shape of stigmatic disc, the number of stigmatic lobes etc. Furthermore these characters never had been chosen for the goal of any practical selection and are modified by the weather conditions as well.

    In the evaluation process the alkaloid accumulation characteristics (both qualitative and quantitative ones) have to be evaluated on a higher rank. For instance the high accumulation level of morphine in cv. 'A1' (10.5 %o), exceptionally high narcotine accumulation in 'Kék Gemona' (7.8 %o), or the low morphine accumulation level in cv. 'Kozmosz' (1.1 %o) proved to be proper characters for their distinction, alone. However, at the same time the weather conditions existing at the time of experiment have to be taken into consideration. From practical point of view, the years rich in precipitation and poor in sunshine are less suitable for distinction of cultivars selected for higher alkaloid accumulation, especially for production of codeine and thebaine characterized by a higher methylation level. Based on the example of 'Kék Gemona', the accumulation level of morphine decreases from 7.4 %o to 4.1 %o under such conditions, while thebaine and codeine disappear, practically.

     

  • New trends in selection of poppy (Papaver somniferum L.)
    69-75.
    Views:
    270

    Since the isolation of morphine by Sertümer in 1805 more than 40 alkaloids have been isolated from the poppy (Papaver somniferum L.). Some of them have high biological-pharmacological activity and economical importance, while others have none, or restricted ones. The increasing demand for poppy alkaloids is the consequence of the widening of the medical application of morphine and its related compounds: the quantity of morphine used for the treatment of pain reached a record level of 17.9 tonnes in 1997, compared with an annual average of 2.2 tonnes used during the period 1978-1983. However, the production of raw material (either opium, or dried capsule is produced) has to be re-evaluated taking into consideration the UN Convention signed in 1988 against Illicit Traffic in Narcotic Drugs and Psychotropic Substances. The countries were forced by the Convention to introduce new arrangements in poppy production including selection and introduction of new cultivars.

    In the present work up to date results of poppy selection are reviewed explaining the biosynthetic and eco-physiological background of their alkaloid accumulation. The effectiveness and the possibilities of traditional selection methods as well as the probability of the application of biotransformation for producing cultivars accumulating low or high alkaloid content or plant material with special alkaloid spectrum (codeine, thebaine, narcotine) are discussed. The examples of Hungarian cultivars 'Monaco', 'Kék Gemona' and 'Tebona' are given in more detail.