In Vitro Propagation of Kaempferia Galanga (Zingiberaceae) and Comparison of Larvicidal Activity and Phytochemical Identities of Rhizomes of Tissue Cultured and Naturally Grown Plants

Kaempferia galanga Linn (Zingiberaceae) is distributed mainly in South East Asia and China [1] and considered as a main ingredient of many traditional Ayurvedic drug preparations [2]. Essential oil in rhizome is volatile and is used as a spice, beverage and also in perfume and cosmetic industries [3,4]. Leaves and flowers contain flavonoids [5]. Main constituents of the rhizome extract contain ethyl-p-methoxycinnamate, ethyl cinnamate, 3-carene, camphene, borneol, cineol, kaempferol and kaempferide which are responsible for many properties of K. galanga [3]. The rhizome of the plant has been reported to possess stimulant, carminative, diuretic and stomachic properties [6]. K. galanga also has biological activities such as antibacterial, antimicrobial, anticancer, larvicidal, amebicidal and pharmacological activities such as vasorelaxant and antiinflammatory properties [7]. The plant has been over exploited and listed under threatened category in Sri Lanka and India and in many other Asian countries. Therefore developing tissue culture techniques for mass propagation of K. galanga would be useful in conservation of this important medicinal plant. Evaluating the potential use of extracts from natural plants and tissue cultured plants on insecticidal activity would be beneficial in using tissue cultured plants as an alternative for natural plants. On the other hand, there is an increasing concern over the use of mosquito coils or vaporizers among general public in which they have a belief that the vapor/smoke from those has ability to cause cancers. As a preliminary study, use of powdered rhizomes of both natural and tissue cultured plants of K. galanga as a potential mosquito repellent has also been evaluated in the present study. There is a possibility of altering biochemical pathways during the tissue culture process due to continuous exposure to excessive amounts of plant growth regulators. Thus, comparison of phytochemicals present in rhizomes of natural plants and tissue cultured plants are necessary if the tissue cultured plants are using as alternative to natural plants.