Anti-nosemosis activity of phenolic compounds derived from Artemisia dubia and Aster scaber

Abstract

The high infection of adult honey bees with Nosema spores is known as nosemosis and can destroy bee colonies. In a previous study, we have reported the anti-nosemosis effect of ethanol and aqueous extracts of Artemisia dubia, Aster scaber, and A. dubia + A. scaber. In the current study, we isolated five phenolic compounds [chlorogenic acid, 3,4-dicaffaeoylquinic acid(3,4-DCQA), 3,5-dicaffaeoylquinic acid (3,5-DCQA), 4,5-dicaffaeoylquinic acid(4,5-DCQA), and coumarin] from A. dubia, A. scaber, and A. dubia + A. scaber aqueous extracts and screened for their toxicities and anti-Nosema effects in both in vivo and in vitro conditions. Among these five compounds, coumarin, chlorogenic acid, and 4,5-DCQA exhibited less toxic but more potent anti-Nosema effects than the other two compounds. Especially, chlorogenic acid and coumarin showed prominent anti-Nosema activities even at the lowest concentration (10 μg/mL). They might have the potential to be developed as alternative compounds for the control of Nosema disease.