THE TOXIGENIC ACTIVITY OF PHENOLIC COMPOUNDS IN TEA TREE, ROSEMARY, EUCALYPTUS AND LAVENDER ESSENTIAL OILS ON MYCOTOXINS PRODUCTION

Aim of this research was to determine phenolic compounds content of tea tree (Melaleuca alternifolia L.), rosemary (Rosmarinus officinalis L.), eucalyptus (Eucalyptus oblique L.), and lavender (Lavandula angustifolia L.) essential oils most used in food and feed industry, and their toxigenic activity on ochratoxin A production. Phenolic quantification was carried out by gas chromatography and gas chromatographymass spectrometric analysis, while compound identifications were performed by comparison of their linear retention indices with standards and homemade library databases. The toxic activities of essential oils were evaluated by inhibiting Aspergillus niger production of ochratoxin A. The measurement of the toxin was performed by high performance liquid chromatography. In the presence of essential oils, the ochratoxin A production depended on the incubation temperature of 20 and 30°C. Our analyses have shown that the M. alternifolia essential oil is richest in terpinen-4-ol, R. officinalis and E. oblique essential oils in 1,8-cineole, and L. angustifolia essential oil in ethanol, 2-(2-ethoxyethoxy)-, also known as carbitol, respectively. It was also found that investigated essential oils could serve as the biocontrol inhibitors against contamination by ochratoxin A in the feed as a natural product