Influence of Monochromatic light on growth, secondary metabolites and antioxidant activity in in vitro culture of Eryngium foetidum L.

Light is a crucial physical component that plants need for growth, morphogenesis and the synthesis of bioactive chemicals. In earlier studies, LED (light-emitting diodes) lights have been utilized to elicit the development of important secondary metabolites. The current study aimed at the stimulatory effect of LEDs on growth, secondary metabolites and antioxidant activity in the in vitro culture of Eryngium foetidum L. The plant in white light had the largest biomass under fresh weight, measuring 4.87±0.02g while the control plant recorded 4.36±0.03g. The condition with the lowest biomass accumulation, dark (2.34±0.24g), was followed by blue light(2.53±0.20g). White light produced the longest shoot (12.22±0.04cm) and the shortest shoot length was measured at 5.67±0.96cm for red light. The plants produced longer roots in red light(6.31±0.06cm) and shorter roots in blue light (3.06±0.51 cm). Red light enhanced the total phenolic content to 0.241±0.12mg gallic acid equivalent/g and flavonoid content to 0.235±0.18mg quercetin equivalent/g in the essential oil extracted from in vitro cultured plant. The essential oil extracted from the plant under red light showed the highest radical scavenging activity compared to other treatments. This study demonstrated that multispectral lighting is a workable alternative for enhancing biomass and secondary metabolites.