Antifungal Activities of Essential Oil Obtained from Mentha Spicata var. Crispa against Selected Penicillium Species

Attention of the scientific community has still focused on application of essential oils (EOs) as natural antifungal agents in the food industry to prolong the shelf-life of food products. In this regard, the current study was designed to evaluate chemical composition, antioxidant capacity, and antifungal (in vitro, in situ) activities of spearmint (Mentha spicata var. crispa) essential oil (SEO) commercially obtained from Slovak company against selected Penicillium species. The EO was used in four concentrations (62.5, 125, 250, and 500 µL/L) chosen, and gas chromatography–mass spectrometry, DPPH, agar disc diffusion and vapor phase methods were employed for such analyses. Our results revealed carvone (57.5%) and α-limonene (17.6%) to be the principal constituents in the EO chemical composition. Although only a weak antioxidant capacity (20.40 ± 0.80% free radical-scavenging inhibition) was displayed by the SEO, the highest EO concentration (500 µL/L) was shown to be a moderate growth inhibitor of P. expansum (inhibition zone of 11.46 ± 0.63 mm) and P. crustosum (inhibition zones of 12.93 ± 0.46 mm). The growth of P. citrinum was only weakly inhibited by the SEO (≥ 250 µL/L). Most importantly, the ability of the SEO to inhibit the mycelial growth of three Penicillium spp. tested was pronounced (P < 0.05) for all applied concentrations. Accordingly, the results from the current study complement our previous ones dealing with the possibility of utilizing diverse EOs commercially achieved from the same company in the food sector.