Effect of UV light on the accumulation of bioactive compounds and expression of related biosynthesis genes in red perilla
2020
Goto, E. | Someya, K. | Ogawa, E. | Hikosaka, S.
Red perilla (Perilla frutescens) is used as food, crude drug, and cosmetics. The major bioactive compounds of red perilla are perillaldehyde, rosmarinic acid, luteolin, and anthocyanin. In this study, we evaluated the effects of UV light on the accumulation of the bioactive compounds and gene expression of related enzymes under controlled environments. Red perilla was cultivated in a controlled-environment room for 35-42 days after germination. The growing condition was air temperature 25/20°C (light/dark), R.H. 70%, light period 16 h, 200 µmol m‑2 s‑1 of PPFD and CO2 conc. 1000 ppm. The plants were exposed to UV-B light of 1.0 W m‑2 for 3 days. The concentrations of perillaldehyde (PA), rosmarinic acid (RA), and anthocyanin (ANT) were measured by HPLC. The expression levels of genes related to RA and ANT synthesis were analyzed by RT-RT-PCR. The PA and RA concentrations at 3 days after the start of UV irradiation increased compared to that of the control. The expression of phenylalanine ammonia-lyase (PAL) and thyrosin aminotransferase (TAT), key genes of the phenylpropanoid pathway for RA synthesis, was higher at 48-72 h in the UV treated plants than those in the control after the start of UV irradiation. The RA concentration increased as a result of antioxidant response to the ROS generated by exposure to UV light. The expression of five genes in the flavonoid pathway increased 24 h after the start of UV irradiation. Total ORAC values of the plants under UV treatment was higher than in the control. Based on the results, we conclude that a short period of UV-B irradiation stimulates the phenylpropanoid pathway for the biosynthesis of RA, and drives the flavonoid pathway for production of ANT, in addition to enhancing the production of other antioxidant compounds.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library