Production of eugenol from genetically true-to-type micropropagated plantlets of holy basil (Ocimum tenuiflorum L.)
摘要
Ocimum tenuiflorum L. syn. Ocimum sanctum L. (holy basil or Tulsi) is highly valued for substantial therapeutic potential owing to the presence of eugenol in its leaves. Eugenol is a bioactive compound known for its versatile healing efficacy. Considering the importance of eugenol in holy basil, in vitro propagation presents a promising and sustainable approach for the consistent production of plant biomass whereby this active compound remains unaltered. The present study established a protocol for accelerated micropropagation of O. tenuiflorum to ensure stable eugenol production. To induce multiple shoot biomass, three cytokinins—meta-Topolin (mT), kinetin (Kn), or 6-benzyladenine (BA)—were supplemented in Murashige and Skoog (MS) nutrient medium at 0.5–1.5 mg L−1 concentrations. The maximum number of shoot formation (4.3) was recorded in 0.5 mg L−1 mT, highlighting its effectiveness as a novel and potent aromatic cytokinin for shoot induction in O. tenuiflorum. Rooting was induced in simple MS medium. Micropropagated plantlets were acclimatized with a 95% survival rate on pre-sterilized soil-sand substratum. The uniformity of the ploidy level and genetic fidelity of micropropagated plantlets was verified by flow cytometry and start codon targeted polymorphism markers. For eugenol estimation from the air-dried leaves, the high-performance thin-layer chromatography analysis was done, which exhibited that the mother plant yielded 3.90 mg g−1 dry weight of eugenol, while the micropropagated plantlets produced a comparable amount of 3.60 mg g−1 dry weight, which justifies the relevance of O. tenuiflorum micropropagation as an alternative sustainable resource of eugenol.