A study on in vitro propagation of Plumbago indica (Ratnetol) and its medicinal properties

Abstract

plumbago indica is a perennial herbaceous plant with long succulent roots. It is an exotic plant, in |lic family Plumbaginaceae and is probably native to Southeast Asia. In Sri Lanka, it is found in jjMlhropogenic localities and only under cultivations. jjlic roots of P. indica are commonly used in indigenous medicine of Ayurveda. It contains an iifiinge yellow pigment named Plumbagin (2-methyl-5-hydroxy-l,4-naphthoquinone) which is the jptlve compound in P. indica. Although it can be easily grown under local conditions, the domestic production is at a minimum lyel due to lack of organized cultivation. It was revealed that more than 90 % of the industrial quirement is imported from India. Ihc main objective of this study was to develop a technology for mass production of Plumbago Indica plants through in vitro propagation and a preliminary analysis of the plant for plumbagin. In vitro propagation is rather difficult as P. indica contains many endophytic microorganisms. Mut washing in soapy water for 15 minutes, keeping under running tap water for 45 minutes, dipping the nodal cuttings in carbendazim™ at concentration of 10.0 g/L for overnight and washing with 70 % Clorox™ for 10 minutes provide a successful method for surface disinfestation of nodal cuttings of P. indica. Murashige and Skoog basic medium (Murashige et al., 1962) supplemented with BAP (6- llcnzylaminopurine) at 3.0 mg/L and IAA (Indole-3-acetic acid) at 0.5 mg/L medium provides Ihc most suitable out of the tested, for proliferation of shoots (100 %). BAP : IAA (3.0 : 1.0 mg/L), BAP : IAA (5.0 : 3.0 mg/L), BAP : AS (Adenine sulfate) (3.0 : 15.0 mg/L) and BAP : AS (3.0 : 10.0 mg/L) media showed 80 %, 46 %, 40% and 40 % shoot proliferation respectively within three weeks in in vitro. Plantlets were acclimatized in the potting mixture of coir : sand : garden soil in 1 : 1 : 1 proportions. Thin Layer Chromatography analysis showed the presence of plumbagin in roots and leaves of in vitro propagated plants