Abstract:
Indole alkaloids (IAs) are biologically very active secondary metabolites, comprise over 3000 compounds. They have enormous pharmaceutical applications and are isolated from various natural sources including plants. For instance, the antihypertensive compound reserpine has been isolated from Rauvolfia serpentine, the antineoplastic compound camptothecine from Camptotheca acuminata, and the antitumor agents’ vinblastine and vincristine from Catharanthus roseus. The immense therapeutic importance and biological activities of Alstonia scholaris are mainly due to the presence of wide range of IAs. However, limited accumulation of such metabolites, particularly in the non-renewable part like bark of tree species, makes their isolation very difficult for commercial purpose. Chemical synthesis of such compounds is also very challenging due to their complex chirality. Therefore, production of medicinally important IAs through different plant tissue culture techniques is an alternate option for their commercial use. Various biotic and abiotic elicitors as well as precursors are generally used for this purpose. In the present study, callus and suspension cultures from Alstonia scholaris were standardized to find out the effects of various elicitors and precursors on the biosynthesis and enrichment of various indole alkaloids. Comparative transcriptome analysis of callus culture of the same plant was done for the identification of genes involved in Indole alkaloids biosynthesis. Seasonal effects on Indole alkaloids accumulation in different parts of wild Alstonia scholaris plant were also studied. Our complete work on this topic is categorized under the following chapters:
Chapter 1 deals with the general introduction of indole alkaloids and their pharmacological applications. It also deals with the problems concerning isolation of indole alkaloids from wild Alstonia scholaris plant as well as their chemical synthesis. The objectives of the whole work like standardization and establishment of callus and suspension cultures from A. scholaris for selected indole alkaloids biosynthesis, study of various biotic and abiotic stresses on indole alkaloids accumulation and enrichment and study of season specific accumulation of targeted indole alkaloids within this plant are also included in this chapter.
