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Klinične okužbe z glivo Candida albicans predstavljajo velik zdravstveni problem, saj gre za patogen, ki po celem svetu povzroča visoko in naraščajočo obolevnost ter umrljivost. Ker se tudi odpornost glivičnih okužb na razpoložljiva protiglivna zdravila povečuje, je smiselno raziskovanje novih potencialnih zdravilnih učinkovin. Alternativo obstoječim zdravilom lahko predstavljajo eterična olja iz aromatičnih rastlin, ki imajo že vrsto let priznano dobro protimikrobno in protiglivno delovanje širokega spektra. Namen tega dela je bilo preveriti zaviralno učinkovitost 35 eteričnih olj (EO) in njihovih sestavin na glivo Candida albicans, za katere protiglivno delovanje še ni dobro poznano, in rezultate primerjati s protiglivno učinkovitostjo petih EO, za katere je bila po do sedaj objavljenih podatkih le-ta visoka. Zaviralno učinkovitost eteričnih olj smo ugotavljali z različnimi metodami: difuzijsko, dilucijsko in fluorescenčno. Ker je eterično olje melise (Melissa officinalis) na podlagi rezultatov teh metod izkazalo najboljše zaviralno delovanje, smo v nadaljevanju sestavo EO melise analizirali z metodo GC-MS in na ta način identificirali ter kvantificirali spojine, prisotne v eteričnem olju. Sestavo EO melise smo primerjali s sestavo EO origana (Origanum vulgare), ki po do sedaj dostopni literaturi velja za najbolj učinkovito protiglivno EO. Ker nas je zanimal sinergizem med spojinami v izbranem eteričnem olju, ki je izkazal najboljše zaviralno delovanje na glivo Candida albicans, smo identificiranim spojinam, katerih koncentracija v EO je znašala več kot 1 % (anetol, 6-metil-5-hepten, beta-kariofilen, geranial, neral, citronelal, kariofilen oksid ter citronelol) ugotavljali zaviralno delovanje posamezne spojine s fluorescenčno metodo. Ugotovili smo, da sta k dobri protiglivni učinkovitosti EO melise največ doprinesli spojini citronelol in citral, ki je zmes dveh izomernih spojin: nerala in geraniala. Rezultati naših raziskav so potrdili, da so eterična olja iz aromatičnih rastlin lahko dobra alternativa obstoječim protimikrobnim zdravilom in da bi bilo smiselno EO melise nadalje raziskovati kot naravno sredstvo za obvladovanje okužb z glivo Candida albicans. Clinical infections with the Candida albicans represent a significant health problem as it is a pathogen causing high and increasing morbidity and mortality worldwide. As the resistance of fungal infections to available antifungal drugs is also increasing, it is worthwhile to research new potential therapeutic compounds. Essential oils derived from aromatic plants, which have been recognized for their broad-spectrum antimicrobial and antifungal properties for many years, can serve as an alternative to existing drugs. The aim of this study was to investigate the inhibitory efficacy of 35 essential oils (EOs) and their components on Candida albicans, for which the antifungal activity is yet not well-known, and compare the results with the antifungal effectiveness of five essential oils, known to be highly effective based on previously published data. The inhibitory efficacy of the essential oils was evaluated using different methods: diffusion, dilution and fluorescence. Based on the results obtained from these methods, the essential oil of lemon balm (Melissa officinalis) exhibited the most potent fungistatic activity. Consequently, the composition of lemon balm EO was analyzed using GC-MS method to identify and quantify the compounds present in the essential oil. The composition of lemon balm EO was compared to the composition of oregano EO (Origanum vulgare), which is considered the most effective fungicide according to the available literature. To investigate the synergy among the compounds present in the selected essential oil that demonstrated the highest inhibitory activity against Candida albicans, we evaluated the inhibitory effects of individual compounds, whose concentration in the EO exceeded 1 % (anethole, 6-methyl-5-heptene, beta-caryophyllene, geranial, neral, citronellal, caryophyllene oxide and citronellol) using the fluorescence method. It was found that the compounds citronellol and citral, which is a mixture of two isomeric compounds geranial and neral, contributed the most to the excellent antifungal efficacy of lemon balm EO. The results of our research confirm that essential oils from aromatic plants can be a good alternative to existing antimicrobial drugs and that it would be reasonable to further investigate lemon balm EO as a natural means of controlling Candida albicans infections.

V magistrskem delu smo testirali protiglivno aktivnost etanolnih in vodnih izvlečkov, pridobljenih iz listov, korenin in socvetij treh vrst pelina (Artemisia verlotiorum, A. vulgaris, A. annua). Protiglivno aktivnost smo testirali z difuzijsko metodo na agarju proti vrstam: Aspergillus flavus, Alternaria infectoria, Fusarium poae, Fusarium oxysporum, Botrytis cinerea in Alternaria alternata. Zaviranje rasti gliv se je med posameznimi izvlečki močno razlikovalo, prav tako se je razlikoval učinek izvlečkov na posamezno glivo. Izvlečki so rast določenih gliv tudi vzpodbudili. Etanolni izvleček listov A. verlotiorum je edini pokazal protiglivno delovanje na vseh testiranih glivah. Rast gliv je najbolj zaviral etanolni izvleček listov vrste A. annua, ki je bil v večini primerov primerljiv s širokospektralnim fungicidom azoxystrobinom. Razlik v delovanju izvlečkov podzemnih in nadzemnih rastlinskih delov ni. Razlike v delovanju etanolnih in vodnih izvlečkov so se pokazale pri izvlečkih A. verlotiorum, ne pa tudi pri A. vulgaris. Med testiranimi rastlinskimi vrstami so imeli izvlečki A. annua največji protiglivni učinek, ki je bil primerljiv z protiglivnim delovanjem azoxystobina. Izvlečki A. annua imajo tako največji potencial za uporabo kot biofungicidi v živilski industriji. In the master thesis we tested antifungal activity of ethanol and aqueous extracts, derived from roots, flowers and leaves of three species of Artemisia (Artemisia verlotiorum, A. vulgaris, A. annua). Antifungal activity was tested with the diffusion method on agar on six different fungal species (Aspergillus flavus, Alternaria infectoria, Fusarium poae, Fusarium oxysporum, Botrytis cinerea and Alternaria alternata). Fungus growth inhibition was differing among different extracts. Extracts have also accelerated the growth of some fungi. Ethanol leaf extract from A. verlotiorum was the only one that had a growth inhibitory effect on all tested fungi. Leaf ethanol extract from A. annua has shown the most antifungal activity and was also comparable with wide spectrum synthetic fungicide azoxystrobin. There were observed differences between extracts from underground and aboveground plant parts. Differences in antifungal activity between ethanol and aqueous extracts were shown for A. verlotiorum, but not A. vulgaris. Among all tested plant species extracts from A. annua have shown the biggest growth inhibitory effects on tested fungi, that were also comparable with azoxystrobin. Therefore A. annua has the most potential as a biological fungicide and for uses in the food industry.

Namen diplomskega dela je bil ugotoviti, ali izbrana eterična olja (EO) delujejo protiglivno. Zato smo jim določili minimalno inhibitorno koncentracijo (MIC) ter minimalno mikrobicidno koncentracijo (MBC) ter njihovo delovanje primerjali z že uveljavljenim razkužilom – vodikovim peroksidom. Testirali smo EO origana (Origanum vulgare), grške bazilike (Ocimum basilicum), sladkega pelina (Artemisia annua), sivke (Lavandula hybrida), laškega smilja (Helichrysum italicum), rožmarina (Rosmarinus officinalis), nemške kamilice (Matricaria recutita) in žajblja (Salvia officinalis) ter vodikov peroksid s kvasovkami vrste Candida albicans in plesnimi vrste Penicillium griseofulvum. Za testiranje protiglivne aktivnosti smo uporabili metodo razredčevanja v mikrotitrski ploščici. Natančne vrednosti MIC in MBC smo za kvasovke določili z metodo štetja kolonij na trdnem gojišču, za plesni pa s pregledovanjem gojišča s plesnimi v mikrotitrskih ploščicah pod lupo. Kvasovke vrste C. albicans so bile bolj dovzetne za EO kot plesni vrste P. griseofulvum. Kvasovkam smo vrednosti MIC določili v območju