Salicylic acid as a stimulator of phenolic metabolism in hairy root cultures of Ocimum basilicum L.

Aim. To investigate the effect of salicylic acid as an elicitor on the accumulation of phenolic compounds in hairy root cultures of two Ocimum basilicum cultivars (purple and lemon). Methods. Basil seeds were introduced into in vitro culture following surface sterilization and cultivated on MS nutrient medium. Hairy root cultures were obtained using the standard Agrobacterium rhizogenes-mediated transformation of leaf explants. To stimulate secondary metabolite synthesis, cultures were elicited with salicylic acid at concentrations of 100 µM, 200 µM, and 300 µM. The total phenolic content was determined spectrophotometrically using the Folin–Denis method. Results. Hairy root cultures of both basil cultivars were successfully established. The application of salicylic acid was found to enhance phenolic compound accumulation in the obtained cultures. For the purple basil cultivar, the maximum phenolic content was observed at a concentration of 200 µM, whereas for the lemon basil cultivar, the optimum was 100 µM salicylic acid. Conclusions. Salicylic acid elicitation is an effective approach for stimulating the biosynthesis of phenolic compounds in hairy root cultures of basil. The optimal elicitor concentration is cultivar-dependent.