Direct somatic embryogenesis in Myristica malabarica Lam., an endemic, threatened medicinal species of Southern India and detection of phytochemicals of potential medicinal value.

Abstract

Direct somatic embryogenesis was obtained from intact and fragmented zygotic embryos of Myristica malabarica, an endemic, threatened medicinal species of Western Ghats of Southern India while cultured in Murashige and Skoog medium containing activated charcoal. In the absence of activated charcoal there was no embryogenic response but only callus formation in zygotic embryos and their fragments. The addition of gibberellic acid resulted in the emergence of shoot from the somatic embryos. The various developmental stages of somatic embryos were examined using scanning electron microscope. Thin layer chromatography revealed the presence of compounds similar to lignans in the embryogenic mass. GC-MS analysis of the embryogenic mass revealed the presence of several compounds of potential clinical value including malabaricone A , αspinasterol and γ- sitosterol. The spent medium showed strong anti-bacterial activity against Pseudomonas aeruginosa. The results are significant since this is the first report of tissue culture and induction of somatic embryogenesis in Myristica malabarica. The embryogenic culture system is potentially useful for efficient and consistent production of bioactive compounds and also has strong implications for conservation of its valuable germplasm. Keywords: Myristica malabarica, activated charcoal, somatic embryogenesis, lignan.