Vertical farms and the controlled environmental conditions they provide can produce high-quality food crops, but these facilities have high construction and operation costs. Therefore, characterizing the growth of high-value crops using these systems is important for the sustainability of vertical farming operations. Catharanthus roseus is a strong candidate for production in vertical farms due to its compact growth habit, quick production timeline, and a secondary metabolite profile with diverse therapeutic potential making it a high-value crop. Two medicinally important secondary metabolites derived from C. roseus are the monoterpene indole alkaloids (MIAs) vincristine and vinblastine which are used as anti-tumor chemotherapy drugs. Extracting these metabolites from field-grown C. roseus is challenging due to low plant yields. Cultivating C. roseus in vertical farms has the potential to increase the yield of these and other desirable plant metabolites by using environmental controls to stimulate relevant metabolite growth pathways. Evidence suggests that these pathways may be influenced by light exposure, but there is limited knowledge concerning the production of C. roseus in vertical farms for alkaloid production. The objective of this study was to identify the effect of light quality and intensity on the growth and alkaloid accumulation of C. roseus grown hydroponically in a vertical farm. We tested two light spectrums (white and white red) with three light intensities (~200, 360 and 500 µmol m-2 s-1) arranged in a factorial randomized complete block design with four replications. High-light treatments expectedly increased plant biomass, while low-light treatments unexpectedly increased vinblastine accumulation. These results demonstrate the feasibility of modifying alkaloid production in C. roseus grown with vertical farm systems, but additional work is needed to identify and optimize environmental conditions for maximizing alkaloid production. This work will inform pharmaceutical studies and other downstream uses of these compounds.
