Iron-induced effect on the chemical composition of Moringa oleifera sprouts

Abstract

To increase the levels of phenolic compounds, flavonoids, and glucosinolates, Moringa oleifera seeds were treated with iron, acting as a stress trigger, during germination. The treatments consisted of adding the elicitor at concentrations of 200, 600, and 1000 ppm directly to the germination substrate, including a control group. We harvested the sprouts at 6, 9, 12, and 15 days after germination and quantified their phenolic compounds, flavonoids, and glucosinolates as well as analysed their antioxidant activity using DPPH, ABTS, and FRAP assays. Overall, the concentrations of these phytochemicals increased compared to the control group, and we observed a similar trend regarding antioxidant capacity. We found that the most favourable results for phenolic compounds came from sprouts harvested on day 15 under the 600 and 1000 ppm iron treatments. We also observed that the highest flavonoid production occurred with the 1000 ppm treatment after 12 days of germination. Across all three methods used, antioxidant capacity yielded the best results with the 1000 ppm treatment at 15 days of germination. All sprouts exhibited higher glucosinolate concentrations than seeds. Iron has the potential to act as a stress-inducing agent in reusable substrates, demonstrated by stimulating phytochemical synthesis during germination.