مهار توليدآفلاتوكسين قارچ Aspergillus parasiticus توسط روغن هاي اسانسي

Inhibition of Aspergillus parasiticus aflatoxin production by essential oils

Aflatoxin B1 produced by Aspergillus parasiticus is highly toxic and carcinogenic. The present study was planned to study antifungal effects of some Iranian plants such as Mentha piperita L. and Eucalyptus camaldulensis var. obtuse on the growth and inhibition or control of aflatoxin production by Aspergillus parasiticus. The plants were dried and hydrodistilled. The chemical constituents of the essential oils thus obtained were identified by GC/MS. Employing disc diffusion and tube dilution methods antifungal effects of the oils on were studied on Aspergillus parasiticus NRRL2999 in-vitro. Zones of microbial growth inhibition and Minimum Inhibitory and fungicidal concentrations (MIC & MFC) of the microorganism exposed to various dilutions of the oils were determined. Quantitative and qualitative production of aflatoxin in control and the test samples exposed to the essential oils, were studied. The oils from M. piperita and E. camaldulensis were inhibitory to the fungal growth and toxin production. Both oils were sporicidal at 500ppm and at lower concentrations the oils had static effect. GC/MS analysis of the oils revealed to identification of the chemical constituents with Isomenthone (10.3%), Trans carveol (14.5%), Piperitenone oxide (19.3%) and a-Terpinene (19.7%) as the major compounds of M. piperita oil. The main compounds in Eucalyptus camaldulensis var. obtuse oil were identified as y-terpinene (7%), Myrcenol (7.4%), a-pinene (9.6%) and 1,8-Cineole (64%). The results indicate feasibility of application of natural sources in the control of growth and aflatoxin production by Aspergillus parasiticus.