Identification of the Effective Components of Ipomoea cairica in Inhibiting Banana Fusarium Wilt and Analysis on Its Bacteriostatic Effect

By exploring the material basis of Ipomoea cairica inhibiting the banana fusarium wilt pathogen (fusarium oxysporum f.sp. cubense), it could provide the lead compounds for the development of green and effective botanical pesticides against banana fusarium wilt disease. The chemical constituents of the ethanol extract of Ipomoea cairica were separated by using the method of column chromatography. The structures of the monomeric compounds were identified by nuclear magnetic resonance spectroscopy and mass spectrometry, and the effects of the compounds on the growth of banana fusarium wilt pathogen (fusarium oxysporum f.sp. cubense) at different concentrations were determined by using the bacteriostatic circle method. The results showed that three monomeric compounds were isolated from the ethanol extract of Ipomoea cairica, which were identified as scopoletin, gallic acid, and β-sitosterol. And the scopoletin at the concentration of 50 μg·mL^-1 could well inhibit the growth of banana fusarium wilt pathogen (fusarium oxysporum f.sp. cubense). Therefore, scopolamine could be used as the lead compound to synthesize a new pesticide which could inhibit the growth of banana fusarium wilt pathogen (fusarium oxysporum f.sp. cubense).