Antifungal activity of alkaloids from aqueous extract of <i>Coptis chinensis</i> against <i>Nigrospora sphaerica</i>

Coptis chinensis is a traditional Chinese herb and the alkaloids in aqueous extract of C. chinensis are natural fungicides. The present study reports the inhibitory effect of aqueous extracts from five medicinal herbs on Nigrospora sphaerica. The aqueous extract of C. chinensis shows highest activity against N. sphaerica among these five herbs. The active alkaloids in aqueous extract of C. chinensis were identified and quantified. The results show that freeze-dried powder of aqueous extract of C. chinensis contains 46.62% berberine, 11.76% epiberberine, 15.88% coptisine, 13.26% palmatine and 3.86% jatrorrhizine. The additive effect among these alkaloids were also determined where the four-compound combination (epiberberine/coptisine/palmatine/berberine) exhibitsexhibits the best inhibitory effect. These findings highlight alkaloids from C. chinensis as promising eco-friendly alternatives to traditional fungicides for integrated pest management.