Chemical composition, antifungal and antioxidant activity of essential oils from Baccharis dracunculifolia and Pogostemon cablin against Fusarium graminearum

Fusarium graminearum Schw. is associated with diseases in seeds and seedlings, mainly in maize, and causes damage to crops and food production. We determined the chemical compositions of essential oils from Pogostemon cablin (Blanco) Benth and Baccharis dracunculifolia DC., and evaluated their antioxidant and antifungal activity against F. graminearum. The oils were applied to the fungus using disc diffusion technique at concentrations of 8.0, 4.0, 2.0 and 1.0 μL mL^-1. Fungistatic effects of P. cablin oil were detectable at 8.0 μL mL^-1, with 80.0% inhibition of fungal growth. This oil contains mono and sesquiterpenes that may be toxic to fungal cell structures. P. cablin oil also had antioxidant activity in free radical sequestration experiments, where as oil from B. dracunculifolia had limited effects. We conclude that essential oil from P. cablin has greater anti-phytopathogenic and antioxidant activity than that from B. dracunculifolia.

Keywords: Baccharis dracunculifolia DC; Fusarium graminearum Schw; Pogostemon cablin (Blanco) Benth; Antifungal; antioxidant; essential oil.