Genetic Transformation of Peganum harmala

Abstract

Peganum harmala L. (Zygophyllaceae) has been a well-known plant in folk medicine and is still used in areas where it is endemic. An incredibly high number of quite different medicinal applications of the seeds and the herb are mentioned in herbal books describing native plants of North Africa and India (Boulos 1983; Ambasta 1986). For example, dried seeds or their extracts are sold as antispasmodicum, anthelminticum, antiasthmaticum, or antirheumaticum at the drug market of Rabat and Algier (Boulos 1983). Though the mode of action of the constituents of P. harmala against many of these quite different diseases is not yet scientifically proven, it is clear that the β-carboline alkaloids of the seeds (up to 6% of dry mass) and serotonin are highly effective psychomimetica (Allen and Holmstedt 1980). Despite the presence of pharmacologically active constituents in P. harmala, the plant has no pharmaceutical importance in Europe and North America. Consequently, the biotechnological interest in in-vitro cultures of this plant as producer of biologically active compounds was low in the past. Indeed, its structures seem to be chemically too simple to be produced via expensive tissue culture technology. Thus the question arises why it has nevertheless been worthwhile to work on this culture system and why it is not only justified, but also useful to continue these studies with genetically transformed cultures. A short summary of the work on untransformed cultures of P. harmala may explain this.