Antifungal activity of oregano extract against A. Versicolor, E. Nidulans and Eurotium spp.: Producers of sterigmatocystin

Abstract

The paper presents the influence of oregano extract (Origanum vulgare L.) on growth of Aspergillus versicolor, Emericella nidulans, Eurotium herbariorum, E. amstelodami, E. chevalieri and E. rubrum - producers of sterigmatocystin (STC) isolated from salads. Antifungal tests were performed by agar plates method. The composition of the active component of extract was determined by GC-MS method and the major components were: carvacrol (34.20%), triacetin (22.91%), carvone (18.05%), p-cymene (8.05%) and thymol (3.74%). The examined extract showed the ability to reduce mold growth at all applied concentrations. Minimum inhibitory concentrations (MIC) for E. nidulans, E. chevalieri and E. amstelodami were 2.5% (v/v) and over 2.5% (v/v) for A. versicolor. At 1.5% (v/v) concentration the extract completely inhibited the growth of E. rubrum, whereas higher dose of 2.5% (v/v) was fungicidal against E. herbariorum. Besides its sensory role in food products, the examined oregano extract also exhibits antifungal activities against producers of STC.

Keywords

• antifungal activity
• oregano extracts
• producers of sterigmatocystin