Eliciting effect of foliar application of chitosan lactate on the phytochemical properties of Ocimum basilicum L. and Melissa officinalis L.

An increase in the content of secondary metabolites in herbal plants is desirable due to their therapeutic and nutraceutical properties. Therefore, the effects of foliar spray of 100 mg/L or 500 mg/L of chitosan lactate (ChL) on the accumulation of selected phenolics and physiological parameters of basil and lemon balm were investigated. In basil, the concentration of rosmarinic acid (RA) increased after application of 100 mg/L of ChL. In turn, in lemon balm both ChL concentrations increased the accumulation of RA and anthocyanins, while the level of total phenolic compounds (TPC) was elevated only at the dose of 100 mg/L of ChL. Elicitation of basil with 500 mg/L of ChL increased the shoot biomass. Therefore, such an elicitor as ChL can enhance the accumulation of valuable phytochemicals in Lamiaceae species. This simple and non-laborious method can be used for elicitation of herbal plants in production of functional food.