Assessing the Effects of LED Irradiation on the Volatile Compounds of Ocimum bacilicum (sweet basil)

Abstract

Sweet basil (Ocimum basilicum L.) is a commonly grown herb valued for its strong aroma and health benefits, which come mainly from its phenolic and volatile compounds. This study examined how supplemental LED lighting affects the volatile compounds in basil. Fresh leaves were analysed immediately after harvest using SPME combined with GC-MS. Seven volatile compounds were identified, including monoterpenoids, sesquiterpenoids, and phenylpropanoids. The use of LED light clearly changed both the type and amount of these compounds compared to sunlight. Phenylpropanoids, especially methyl chavicol and methyl eugenol, were significantly higher under red LED light, with methyl chavicol being the most dominant. Sesquiterpenoids like α-bergamotene and τ-cadinol increased under red and white LEDs, while α-humulene was higher under red light. Monoterpenoids showed mixed responses, with camphor increasing under white LED and γ-selinene under red LED. These results indicate that LED lighting can enhance the quality and economic value of basil for food, pharmaceutical, and fragrance uses.