In-vitro Mycological activity of essential oil from Zingiber zerumbet rhizomes

The volatile oil (1.12%) from the Z. zerumbet rhizomes were extracted using Clevenger’s distillation.
The GC and GC-MS profile of the Z. zerumbet volatiles revealed several components of which
Zerumbone was the principal compound (49.8%) followed by α-Caryophyllene (20.1%) and trace
of other compounds. The antifungal property of volatiles was studied against Aspergillus flavus and
Aspergillus ochraceus. The fungal species were susceptible to volatiles, and the minimum fungicidal
concentration (MFC) was 160 ppm for A. flavus and 175 ppm for A. ochraceus.The studies with the
food toxigenic organisms treated with volatiles were significant. It revealed substantial inhibition
of mycelia, spore germination, reduction in biomass, carbohydrate, protein, chitin and genetic
constituents. The inhibitory action of zerumbet volatile oil on A. flavus and A. ochraceus involves
cell wall damage and distortion in the metabolism. The SEM of A. flavus and A .ocharceus illustrates
that treatment with the oil leads to distortion of hyphae and the absence of conidiophores. The Z.
zerumbet volatiles (100 ppm) were found to be antimycotoxin on maize as food substrates and were
dose-dependent on confirmation by HPLC. Z. zerumbet oil is potentially useful as biopreservative
because of its antifungal and antimycotoxin efficacy.