Effect of light-emitting diode (LeD) on contents of lignans and anthocyanins in Schizandra chinensis

Abstract

Light-emitting diode (LED) is a semiconductor light source and it is known to enable plants to grow quickly and increase the secondary metabolites because it provides plants with light of specific wavelength, necessary for growth of plants. Fruits of Schizandra chinensis have been used for reduction of blood pressure and fatigue and protection of brain in Korea. Its bioactive constituents are known to be a series of lignans and anthocyanin pigments. In this study, we tried to investigate how LED has an influence on contents of four major lignans (schizandrin, deoxyschizandrin, gomisin A, and gomisin N) and anthocyanin in this medicine. The fruits of S. chinensis were placed under the LED wavelengths at 440nm, 470nm, 660nm, white LED, and dark (control) for 1, 3, 7, 14, 21, 28 days, respectively. The contents of four lignans were investigated based on peak area of HPLC chromatograms under UV detection at 254nm, while those of anthocyanin were measured based on UV absorption at 400–600nm. In result, contents of the lignans increased under the 440nm and dark conditions by 21 days, even though there is some fluctuations under other wavelengths. In addition, those of anthocyanin were the most at 440nm and white LED. Detailed results and discussion on contents of lignans and anthocyanin by wavelengths will be presented.