Effect of light on biosynthesis of alkamide, caffeic acid derivatives and echinacoside in Echinacea purpurea L. callus cultures

Abstract

Light is not only effective in photosynthesis, growth and development, but also play an important role in biosynthesis of primary and secondary metabolites. The present research was aimed to determine effect of light on biosynthesis of alkamide, caffeic acid derivatives and echinacoside in cell suspension cultures of Echinacea purpurea L. Stem explants derived from sterile plants were subjected to callus culture in a B5 media supplemented with 1.0 mg/L BAP and 2.0 mg/L NAA. Afterward, 8-day cell cultures were incubated in light and dark environments and cell harvesting, with a three-day interval, was carried out five times. The contents of alkamide, caffeic acid derivatives and echinacoside were determined using HPLC. Alkamide, caftaric acid and echinacoside content increased regularly with light application. Light application increased alkamide content by 57%, as an average, compared to darkness. The cell cultures exposed to 12 days of incubation in light produced the highest alkamide content, with a 2.11-fold increase, compared to dark. Subjecting the cell cultures to light for 12 days resulted in 70% and 63% increases in caftaric acid and echinacoside. This study showed that light application in Echinacea purpurea L. cell suspension culture had a great potential for increasing some important phytochemicals.