The effect of different light wavelengths on metabolomic changes of mint and pennyroyal

Increasing trend in global population and climate changes are driving forces to shift toward the use of vertical farms with artificial lighting (VFALs). The main downside of VFALs is inefficient electrical usage. High efficiency and economy cost of light-emitting diodes (LED) are going to make VFALs a promising type of farming in future. Each individual species needs unique light treatment in order to achieve maximal qualitative and quantitative production. Lamiaceae family includes plant species with high economic value and applications in medicinal and cosmetic industry.  In the present study, we selected six light treatments including LED (red, blue, red-blue (70:30), white), florescent, and natural light to evaluate metabolomic changes in two species of Lamiaceae family (mint and pennyroyal). At flowering stage, fresh leaves were collected from plants to analyze for metabolic constituents using Head Space sampling technique and GC-MS. The results indicated light treatment had effect on metabolic profile of mint and pennyroyal plants. It was found that the application of red-blue LED maximized the concentration of beneficial monoterpenes suggesting that the production of selected genotypes is possible in environments without natural light such as VFAL systems.