In vitro conservation strategy for sustainable utilization of Premna serratifolia L. : A potential medicinal plant

Premna serratifolia is a perennial shrub known for its wide range of therapeutic values and is used extensively in the Indian System of Medicine. Even though it is ranked as a species of least concern by the IUCN red list (September 2020), habitat degradation, wood harvesting, and overexploitation ensure a decline in its populations. P. serratifolia is one of the key components in Dasamoola rasayanam preparation in Ayurvedic system of medicine. To support its prolonged sustainability and reduce wild harvesting, the present study focuses on in vitro mass production of callus from leaf and stem explants of P. serratifolia, and its qualitative screening. Callus induction varied depending on the explant type and auxin combinations. IAA alone induced maximum callusing at 7.0 mg/L in leaf explants (100%) and at 5.0 mg/L in stem explants (89%), while the combination of IAA and 2,4-D enhanced callus induction to 100% in stem explants (3.0 mg/L) and 89% in leaf explants (5.0 mg/L). Interestingly, the NAA and 2,4-D combination exhibited a synergistic effect in stem explants, whereas in leaf explants it showed an antagonist effect. Although the metabolites identified in the in vitro–derived callus include alkaloids, flavonoids, phenols, tannins, terpenoids, and reducing sugars, the successfully induced callus cultures exhibit significant potential for medicinal applications through the production of valuable secondary metabolites. Moreover, this approach provides a sustainable and efficient strategy for the conservation of Premna serratifolia, while simultaneously enabling the large-scale production of bioactive compounds.