Anti-fungal activity of Citrus reticulata Blanco essential oil against Penicillium italicum and Penicillium digitatum

The chemical composition of Citrus reticulata Blanco essential oil was analysed using GC/MS. Monoterpene hydrocarbons (C10H16) constituted the majority (88.96%, w/w) of the total oil. The oils dose-dependently inhibited Penicillium italicum and Penicillium digitatum. The anti-fungal activity of the oils against P. italicum was attributed to citronellol, octanal, citral, decanal, nonanal, β-pinene, linalool, and γ-terpinene, whereas anti-fungal activity against P. digitatum is attributed to octanal, decanal, nonanal, limonene, citral, γ-terpinene, linalool, and α-terpineol. The oils altered the hyphal morphology of P. italicum and P. digitatum by causing loss of cytoplasm and distortion of the mycelia. The oils significantly altered extracellular conductivity, the release of cell constituents, and the total lipid content of P. italicum and P. digitatum. The results suggest that C. reticulata Blanco essential oils generate cytotoxicity in P. italicum and P. digitatum by disrupting cell membrane integrity and causing the leakage of cell components.