Longitudinal Expression of Antioxidant Phytochemicals in Buckwheat (Fagopyrum esculentum Moench)

Abstract

Buckwheat is a source of rutin and other antioxidant phytochemicals. Rutin is highest during the flowering stage of crop growth. A longitudinal study was performed in the spring of 2007 to characterize the expression of other antioxidant phytochemicals from sprout to seed development on a large scale farming operation. Carotenoids decreased during the growth of the plant, while the rutin and anthocyanin concentrations peaked between weeks 4–5 before declining. Total phenolics increased and were maximal between weeks 4–7. There was no change in vitamin E levels. Antioxidant activity against iron induced oxidation was not different during the growing period; however, the antioxidant activity against a peroxyl radical increased over the experiment and was maximal 7 weeks after sowing. Based on summary of the data, the optimal harvest time to enhance antioxidant and phytochemical content of buckwheat plants is between 4–5 weeks after sowing.