In our research, we are manipulating certain environmental factors that may affect the presence of phytochemicals in Peperomia pellucida, one of these being light as this plant thrives in mostly moist and shaded areas.
Dear Margarita, Perhaps light intensity will play a major role in experiments associated with plant thriivng in moist and shady area as it will act as limiting factor and also as a source of stress which will indirectly influence the phytochemical content of the target plant species.
Don't forget light quality i.e. red or far red. So you could also add light filtration to intensity and photoperiod. Test all of them – the more, the better lol! :)