Antifungal Activities and Chemical Compositions of Essential Oils from Leaves of Four Eucalypts

Essential oils from the leaves of 4 eucalypts species, i.e., Eucalyptus urophylla, E. grandis, E. camaldulensis, and E. citriodora, were by extracted hydrodistillation. Compositions of the essential oils were analyzed and identified. Their biological activities with respect to antifungal activity were examined. Yields of the essential oils in descending order were E. camaldulensis (3.48 mL/100 g), E. urophylla (3.14 mL/100 g), E. grandis (3.01 mL/100 g), and E. citriodora (1.89 mL/100 g). Anti-mildew tests of the 4 eucalypt essential oils indicated that E. citriodora had the best efficacy, and was extensively effective against all tested mildews. E. urophylla, on the other hand, had the poorest efficacy. On the wood decay fungus tests, the same was observed for E. citriodora essential oil, and this indicated that it might be used as an excellent wood preservative. The main reason for its effectiveness was the presence of citronellol and citronellal which had obvious benefits in fighting mildew and fungi.