Growing High Quality Plant Material for Natural Health Products

Natural health products are commonly made from plant material in facilities where they can be stored for weeks to years. For stable ingredients, this process does not significantly change the phytochemical composition, but products with less stable bioactive phytochemicals such as melatonin are being introduced. Plant sourced melatonin, known as “phytomelatonin”, is the basis for a new line of nutraceuticals that are recommended for sleep disorders and anxiety. However, due to its lower stability, melatonin may have a short shelf-life. Therefore, methods to increase melatonin concentration in medicinal plants could provide better supplements. We hypothesized that varying light spectra changes melatonin and serotonin contents in tissues of Hypericum perforatum (St. John's Wort) and Scutellaria species (skullcap). Axenic cultures were exposed to red, blue, green or white light spectra provided by light emitting diode lighting systems, then serotonin and melatonin were quantified by ultra performance liquid chromatography-tandem mass spectrometry. Our data shows that in St. John's Wort, melatonin concentration is significantly affected by light spectra with the highest values in green light, and decreasing concentrations in the order of red, blue, white and fluorescent light (p < 0.001). In Scutellaria lateriflora and S. galericulata, the concentration of abscisic acid (ABA) was the highest under white light (p = 0.004 and p = 0.012, respectively). ABA concentration in S. galericulata had a decreasing trend under exposure of green, blue and red LED light. It is important to optimize the growth of plants as the demand for plant-based products grows. By optimizing the growth of the plant through the use of light, we can improve the medicinal chemical profile to improve products.