Abstract
The leaves of Catharanthus roseus (L.) G. Don produce vindoline (VDL) and catharanthine (CAT). These two compounds are used as components of important and expensive anti-cancer drugs such as vinblastine and vincristine. Our previous study indicated the production of VDL and CAT under red light irradiation was greater than the production under blue light, a mixture of red and blue light, and fluorescent lamp-based white light (Fukuyama et al., 2013). The aim of this study was to determine the optimal red light intensity for maximizing production of VDL and CAT. The plants were cultivated hydroponically in an environmentally controlled room under a 16-h photoperiod and four different red light intensities: 75, 150, 300, and 600 μmol m−2 s−1. The fresh weight of total leaf of the plants grown under 300 μmol m−2 s−1 was the greatest, and VDL and CAT concentrations of the plants grown under 150 μmol m−2 s−1 were the greatest compared to the other treatments. Therefore, optimal red light intensity for VDL and CAT production was suggested to be between 150 and 300 μmol m−2 s−1. We expect that these results will contribute to the development of a stable material source for important and expensive pharmaceutical drugs.
