Essential oils from oregano (Origanum vulgare L.), mint (Mentha piperita L.), fennel (Foeniculum vulgare Mill.), and pine (Abies alba Mill.) needles and cones, and their active substances thymol, ...carvacrol, menthol, and anisaldehyde were tested for antifungal activity against Penicillium verrucosum. The lowest minimal inhibitory concentrations (MICs) were achieved for essential oil of oregano, followed by carvacrol, thymol, and menthol. These antifungal components were further investigated, as the main aim of our study was to elucidate the effect of natural antifungals on ochratoxin A production. During 21 days of exposure, the growth of P. verrucosum, and subsequently the production of ochratoxin A, was fully inhibited by thymol at ½ MIC (0.0625 mg mL
), but menthol at ¼ and ½ MIC (0.1875 and 3750 mg mL
) showed no growth inhibition. After 21 days of incubation, the greatest inhibitory effect on ochratoxin production (inhibition was 96.9 %) was also achieved with thymol at ¼ MIC (0.0313 mg mL
). Essential oil of oregano (¼ MIC, 0.2930 μL mL
) and carvacrol (½ MIC, 0.1953 μL mL
) stimulate production of ochratoxin A at 13.9 % to 28.8 %, respectively. The observed antifungal effects depended on the agent, the concentration used, and the time of interaction between the agent and P. verrucosum. Our results indicate the possibility of using oregano essential oil as a substitute for artificial preservatives in certain foods, but further research is needed.
Eterična olja origana (Origanum vulgare L.), mete (Mentha piperita L.), janeža (Foeniculum vulgare Mill.), in borovih (Abies alba Mill.) iglic in storžev, ter njihove sestavine timol, karvakrol, mentol in anisaldehid smo testirali kot snovi z protiglivno aktivnostjo proti plesnim vrste Penicillium verrucosum. Najnižje minimalne inhibitorne koncentracije (MICs) smo določili eteričnemu olju origana, ter karvakrolu, timolu, in mentolu. Rast plesni vrste P. verrucosum je bila popolnoma inhibirana po 21 dneh inkubacije v prisotnosti ½ MIC timola (0,0625 mg mL-1), medtem ko so eterično olje origana (½ MIC, ¼ MIC), timol (¼ MIC) in karvakrol (½ MIC, ¼ MIC) inhibirali rast plesni od 8,3 % do 70.8 %. Dodatek mentola v koncentracijah ¼ MIC in ½ MIC (0.1875 mg mL
in 0.3750 mg mL
) pa ni imel inhibitornega vpliva na rast plesni vrste P. verrucosum. Popolno inhibicijo tvorbe ohratoksina A smo določili le v primeru, ko je bila tudi rast teh plesni popolnoma inhibirana (pri ½ MIC timola). Največjo inhibicijo tvorbe ohratoksina A (96,9 %) po 21 dnevih inkubacije smo določili pri ¼ MIC timola (0.0313 mg mL
). Pospešeno tvorbo ohratoksina A (od 13,9 % do 28,8 %) pa smo določili pri ¼ MIC eteričnega olja origana (0.2930 mg mL
) in ½ MIC karvakrola (0.1953 mg mL
). Protiglivni vplivi so bili odvisni od testirane snovi, njene koncentracije ter časa interakcij med protiglivno snovjo in plesnimi vrste P. verrucosum. Rezultati nakazujejo možnosti uporabe eteričnega olja origana v živilih namesto kemijskih konzervansov. Ker pa so živila kompleksna okolja v katerih je potrebno upoštevati več dejavnikov, so potrebne nadaljnje raziskave.
Listeria monocytogenes is a foodborne pathogen responsible for listeriosis. The inhibitory effect of essential oils (1% v/w) of Thymus daenensis Celak (Lamiaceae), Thymbra spicata L. (Lamiaceae) and ...Satureja bachtiarica Bunge (Lamiaceae) applied to the surface of chicken frankfurters was determined on L. monocytogenes inoculated at low (103 CFU/g) and high (106 CFU/g) populations and stored for seven and 14 days. The results showed that L. monocytogenes populations increased during seven and 14 days of storage at 4 °C on control frankfurters without essential oil. The application of 1 % essential oil (v/w) of herbs to frankfurter surfaces can significantly reduce (p<0.05) the L. monocytogenes populations as compared to control in two inocula treatments after seven and 14 days of storage at 4 °C.
Listeria monocytogenes je povzročitelj listerioze, ki se pojavlja v živilih. Proučevan je bil inhibitorni učinek eteričnih olj (1% v/w) zelišč Thymus daenensis Celak (Lamiaceae), Thymbra spicata L. (Lamiaceae) in Satureja bachtiarica Bunge (Lamiaceae), nanešenih na površino piščančjih hrenovk, ki so bile inokulirane z nizko (103 CFU/g) oziroma visoko populacijo (106 CFU/g) listerije ter shranjene za 7 oziroma 14 dni. Rezultati so pokazali, da se populacije L. monocytogenes povečajo tekom 7 oziroma 14 dni shranjevanja pri 4 °C na primerjalnih hrenovkah. Uporaba 1 % (v/w) eteričnih olj zelišč pri hrenovkah lahko značilno (p<0.05) zmanjša populacijo L. monocytogenes v primerjavi s kontrolo.
Essential oils composition of hydroponically grown Ocimum basilicum L. plant was evaluated in response to salinity (control and 50 mM NaCl) and Zn foliar application (control, 100 and 200 mg l-1). ...Essential oil constituents were quantified and identified by GC/EI-MS. In total, fifty seven components were identified in the six treatment combinations. Methyl chavicol (43.9-61.2 %) and linalool (11.4-16%) were the major components of all treatments. Salinity had deteriorative effect on methyl chavicol biosynthesis and accumulation. In contrast, integrated levels of salinity and 200 mgl-1 Zn had increment effects on linalool content. Germacrene D (2.2-3.9 %), 1,8-cineole (2.4-3.8 %), (Z)-α-bergamotene (0.1-2.6 %), (E)-β-farnesene (1.4-2.6 %), α-bulnesene (0.9-2.4 %), camphor (0.7-1.3 %) and (E)-β-ocimene (0.2-1.3 %) were the other main common constituents of oil. Considering the constant levels of zinc foliar application, salinity had raising effects on the contents of most above mentioned constituents. In conclusion, it seems that moderate salinity stress along with balanced levels of Zn foliar application changed the primary metabolites pathways in favor of major volatile oil components biosynthesis and that basil plant has the production potential under prevalent semi-saline conditions.
Raziskana je bila sestava eteričnih olj hidroponsko gojene bazilike (Ocimum basilicum L.), glede na vpliv slanosti (kontrola in 50 mM NaCl) ter foliarnega nanašanja cinka (Zn) (kontrola ter 100 oziroma 200 mg l-1). Sestava eteričnih olj je bila ugotovljena z GC/EI-MS tehniko. Pri šestih kombinacija tretiranja je bilo ugotovljenih 57 sestavin. Metil kavikol (43,9-61,2 %) in linalool (11,4-16%) sta bili glavni sestavini pri vseh tretiranjih. Sol je negativno vplivala na sintezo in akumulacijo kavikola. Nasprotno, skupen vpliv solne raztopine in višje koncentracije cinka je povzročil povečanje vsebnosti linaloola. Germakren D (2,2-3,9 %), 1,8-kineol (2,4-3,8 %), (Z)-α-bergamoten (0,1-2,6 %), (E)-β-farnesen (1,4-2,6 %), α-bulnesen (0,9-2,4 %), kafra (0,7-1,3 %) in (E)-β-ocimen (0,2-1,3 %) so tudi bile glavne sestavine olja. Pri nespremenjeni koncentraciji cinka pri foliarni aplikaciji je sol vplivala na povečano koncetracijo omenjenih metabolitov. Zmerna slanost skupaj s foliarnim tretiranjem z raztopino cinka vpliva na spremenjeno sestavo metabolitov s tem da poveča biosintezo hlapnih sestavin olj; tako je ugotovljena prednost pridelovanja bazilike v razmerah zmerne slanosti.