Rapid regeneration and analysis of genetic fidelity and scopoletin contents of micropropagated plants of Spilanthes oleracea L.

Abstract

SummarySpilanthes oleracea L. is an important medicinal plant used in traditional medicine for curing toothache, stammering, and stomatitis. Axillary shoots were induced from nodal explants on semi-solid and liquid 1.0 × Murashige and Skoog (MS) media supplemented with 1.0, 2.0, 5.0, or 1.0 µM 6-benzylaminopurine (BAP), kinetin (Kn), 2-isopentenyl adenine (2-iP), or thidiazuron (TDZ). The highest number of axillary shoots (mean = 74.3 shoots per explant) were regenerated on liquid 1.0 × MS medium supplemented with 2.0 µM Kn. Liquid medium was found to be more suitable for shoot induction compared to semi-solid medium (mean = 45.5 shoots per explant). Shoots were rooted on semi-solid 0.5 × MS medium supplemented with 10 µM α-naphthaleneacetic acid (NAA). The resulting plantlets were acclimatised in a growth chamber. Random amplified polymorphic DNA (RAPD) marker analysis revealed that the regenerated plants did not exhibit any genetic polymorphism. Scopoletin (6-methoxy-7-hydroxycoumarin) concentrations were determined in regenerated plants as well as in in vivo plants using high performance liquid chromatography (HPLC). Analysis revealed that in vitro-regenerated plants had higher amounts (mean = 3.42 µg g–1 DW) of scopoletin compared to in vivo plants (range 0.01 – 3.04 µg g–1 DW). Liquid 1.0 × MS medium could therefore be used for large-scale propagation of this plant, and the regenerated plants could serve as raw material for the extraction of scopoletin.