Aims
This study aimed to investigate the inhibitory effect of tannic acid (TA) on the growth of Apiospora arundinis and 3-Nitropropionic acid (3-NPA) production.
Methods and results
To investigate the antifungal mechanism, the effects of TA on the hypha growth, electrical conductivity, hypha morphology, defence-related enzymes and 3-NPA production of A. arundinis were studied. TA concentrations of 640 and 1280 μg⋅mL−1 exhibited strong antifungal activity against A. arundinis. The results of SEM and TEM showed that the hypha of the A. arundinis was severely deformed after TA treatment, and the cell membrane was blurred and thin, vacuoles were obviously shrunken and smaller, and most of the organelles were decomposed into irregular fragments. The increased of electrical conductivity and MDA content indicated that TA caused peroxidation of unsaturated fatty acids and damaged the structure of the cell membrane. The decrease of intracellular ATP and SDH content indicated that TA damaged the function of mitochondria, participated in the inhibition of respiratory metabolism. In addition, TA significantly reduced 3-NPA production, and completely inhibited 3-NPA production at 640 and 1280 μg⋅mL−1.
Conclusion
TA effectively inhibited both growth of A. arundinis in vitro and 3-NPA production.