Human Gene Expression as a Tool To Determine Horticultural Maturity in a Bioactive Plant (Echinacea purpureaL. Moench)

Abstract

A phenological study was conducted to determine the impact of harvest maturity on the immune-modulating properties of Echinacea purpurea. The aerial parts of this plant were collected during seven stages of development and were assayed for a common botanical marker for this species, cichoric acid. Plants of selected development stages were also assayed for total polysaccharides and compared for their immune-modulating effects on the THP-1 monocyte/macrophage cell line by means of a gene expression study. Although the concentration of cichoric acid did not change significantly during the course of the study, stage 1 (advanced vegetative) had the highest concentration of total polysaccharides and exhibited the most potent induction activity on immune-modulating cytokines such as interferon-γ and tumor necrosis factor-α. These findings suggest that the use of gene expression may be an effective tool not only to standardize botanical extracts but also to optimize harvest time. Keywords: Harvest maturity; Echinacea; botanical marker; cichoric acid; polysaccharides; immune-modulating effects; gene expression