Influence of Allium ampeloprasum L. and Allium cepa L. essential oils on the growth of some yeasts and moulds

Essential oils extracted from spices, as natural antimicrobial agents, attract particular attention due to their possible role in food protection from microorganisms, and their nontoxicity, in contrast to the synthetic preservatives. In this work, inhibitory effect of Allium ampeloprasum and two onions (Allium cepa), Junski srebrnjak and Kupusinski jabučar, essential oils in different concentrations (1, 4, 7 and 10%) on three yeasts (Saccharomyces cerevisiae, Candida tropicalis and Rhodotorula sp.) and three moulds (Aspergillus tamarii, Penicillium griseofulvum and Eurotium amstelodami) was investigated. All three essential oils showed the strongest inhibitory effect against S. cerevisiae in concentration of only 1%. Among onions, Kupusinski jabučar essential oil had stronger influence to C. tropicalis, while Allium ampeloprasum essential oil did not show any influence on this yeast. Rhodotorula sp. was influenced only by Allium ampeloprasum essential oil. The strongest inhibitory effect on A. tamarii showed Kupusinski jabučar (57% of inhibition, in concentration of 10%), while on P. griseofulvum, the strongest influence showed Allium ampeloprasum essential oil (78.3% of inhibition, in concentration of 10%). Junski srebrnjak and Kupusinski jabučar essential oils, in concentrations of 7 and 10% respectively, completely inhibited the growth of E. amstelodami