Effect of Light Quality on the Polyphenol Content and Antioxidant Activity of Sweet Basil (Ocimum basilicum L.)

Sweet basil contains some phenolic compounds such as rosmarinic acid, caffeic acid, and chicoric acid. Our previous study revealed that the rosmarinic acid content was increased by continuous white light irradiation. In this study, we investigated whether light conditions affect the caffeic acid and chicoric acid contents. The content of chicoric acid was increased by light irradiation, and was highest under white light, followed by blue light, and was lowest was under red light. Although the content of caffeic acid was also increased by light irradiation, it was not influenced by light quality. These results indicate that continuous white light increases the polyphenol content of sweet basil, which results in high antioxidant activity.