Viktor József Vojnich

EFFECT OF NITROGEN AND MAGNESIUM NUTRITION ON INDIAN TOBACCO (LOBELIA INFLATA L.)

Lobelia inflata L. a native North- American species is reported to possess pharmaceutically significant properties. Our experiments aimed at introducing this species to Hungary and implemented in randomized blocks with 4 repetitions, indicate the favourable effects of Mg-fertilization. Based on our results, it can be estimated that under the influence of Mg treatment an established population of Indian tobacco can produce some 3.2 kg*ha-1 total alkaloids.

Increasing the Anti-Addictive Piperidine Alkaloid Production of In VitroMicropropagated Indian Tobacco by Nitrate Treatments

Background: Lobelia inflata L. (Indian tobacco) is a traditional medicinal plant native to North America. It contains several piperidine alkaloids. Interest in Lobelia alkaloids, and in particular (-)-lobeline, the most active component, has increased in recent years due to their effect on the central nervous system. Thus, lobeline is currently the subject of renewed interest for its anti-addictive activity in the treatment of drug abuse, and neurological disorders. Our studies were aimed at introducing this species into cultivation in Hungary. Results: For direct characterization of di-substituted and mono-substituted piperidine alkaloids in extracts of L. inflata, a tandem mass spectrometric method was developed using electrospray ionization. The compounds (-) lobeline, norlobeline, lobelanidine, norlobelanine and other related structures were identified by HPLC-MS/MS. With the aim of increasing the alkaloid production, we have investigated the effect of changing the ammonium and potassium nitrate levels of the basic Murashige-Skoog medium. The highest dry mass, total alkaloid and lobeline content were measured in the herbs and roots cultured at 570 mg L-1 KNO3 content. Conclusions: The highest values for lobeline derivatives norlobeline and lobelidine were also recorded in the herba and roots of Lobelia inflata cultured on reduced KNO3 containing MS medium. The most sensitive response to media modification was observed in the case of lobelidine. Double-concentration of NH4NO3 had an inhibitory effect on plant growth, total alkaloid and lobeline content.