Protimikrobno delovanje eteričnih olj na bakterije Legionella pneumophila : magistrsko delo

Ribič Kovač, Kaja (avtor), Oder, Martina (mentor), Fink, Rok (recenzent)

Uvod: Bakterije iz rodu Legionella so povzročiteljice bolezni, ki jih skupno imenujemo legioneloze. Do okužbe z bakterijami Legionella lahko pride povsod, kjer so le-te prisotne v dovolj velikem številu ter prihaja do pršenja vode in nastanka aerosolov. Tveganje je večje v vodovodnih sistemih stavb, kjer je temperatura vode med 20 in 50 °C. Za preprečevanje razmnoževanja oziroma odstranjevanje bakterij Legionella uporabljamo fizikalne in kemične pristope, vendar so ti velikokrat neučinkoviti ali pa zaradi pogoste uporabe agresivnih razkužil prihaja do poškodb vodovodnih cevi in naprav. Namen: Namen raziskave je bil ugotoviti vpliv naravnih protimikrobnih sredstev eteričnih olj čajevca in limoninega evkaliptusa na bakterije Legionella pneumophila. Metode dela: Za ugotavljanje intenzivnosti razmnoževanja bakterij Legionella pneumophila pri izpostavljenosti različnim koncentracijam smo analizirali protibakterijski potencial izbranih naravnih izvlečkov z mikrodilucijsko metodo. Rezultati: Rezultati so pokazali, da je eterično olje čajevca učinkovito delovalo proti nastanku biofilma pri vseh treh bakterijskih sevih Legionella pneumophila. Najučinkoviteje je delovalo na bakterijo Legionella pneumophila sev 130b, izolirano iz naravnega okolja. Pri MIK 1 smo dosegli 50-% učinkovitost pri preprečevanju nastanka biofilma, pri MIK 2 53-%, pri MIK 3 pa kar 56-% učinkovitost. Najmanjšo učinkovitost eteričnih olj za preprečevanje nastanka biofilma smo dokazali pri bakteriji Legionella pneumophila subsp. ATCC 33152, kar kaže na to, da je omenjena bakterija na delovanje eteričnih olj bolj odporna kot ostali dve. Razprava in zaključek: Tekom raziskave smo ugotovili, da ima eterično olje čajevca največjo učinkovitost proti nastanku biofilma in ima protibakterijske učinkovine. Izkazalo se je, da so njegove učinkovine imele pozitiven vpliv na preprečevanje nastanka biofilma. Razvoj na področju zelene kemije predstavlja obetavno alternativo klasičnim postopkom zaviranja rasti in razvoja biofilmov, saj bi z nadaljnjimi poglobljenimi raziskavami lahko pripomogli k zmanjšani uporabi klasičnih metod ter posledično k manjši mikrobni odpornosti in prekomerni uporabi klasičnih protimikrobnih sredstev. Potrebne bi bile nadaljnje raziskave na tem področju, da bi ugotovili učinkovitost dejavnih komponent na različnih bakterijskih sevih hkrati z možnostjo sinergističnega delovanja različnih eteričnih olj.

• Jezik: Slovenski jezik
• Ključne besede: magistrska dela, sanitarno inženirstvo, Legionella pneumophila, biofilmi, legioneloza, protibakterijsko delovanje naravnih snovi
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: ZF - Zdravstvena fakulteta
• Kraj izida: Ljubljana
• Založnik: [K. Ribič Kovač]
• Leto izida: 2023
• Št. strani: 42 str.
• PID: 20.500.12556/RUL-144780
• UDK: 614
• COBISS.SI-ID: 144852483
• Datum objave v RUL: 12.03.2023

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Antimicrobial activity of essential oils on bacteria Legionella pneumophila : master thesis

Izvleček

Introduction: Bacteria of the genus Legionella are the cause of diseases collectively called legionellosis. Infection with Legionella bacteria can occur wherever they are present in sufficiently large numbers, and where water spray and generation of aerosols occur. The risk is greater in the water supply systems of buildings where the water temperature is between 20 and 50 °C. Physical and chemical approaches are used to prevent the reproduction of Legionella bacteria or to eliminate it, but these are often ineffective or may cause damage to plumbing and equipment due to the frequent use of aggressive disinfectants. Purpose: The aim of the research was to determine the effect of natural antimicrobial agents of tea tree and lemon eucalyptus essential oils on Legionella pneumophila bacteria. Methods: To determine the reproduction intensity of Legionella pneumophila bacteria at different concentrations, the antibacterial potential of selected natural extracts was analysed using the microdilution method. Results: The results showed that tea tree essential oil was effective in preventing biofilm formation in all three bacterial strains of Legionella pneumophila. It was most effective against Legionella pneumophila strain 130b bacterium, isolated from its natural environment. We achieved a 50% efficacy in preventing biofilm formation at MIC 1, a 53% efficacy at MIC 2, and a 56% efficacy at MIC 3. The lowest efficacy of essential oils in preventing biofilm formation was demonstrated in Legionella pneumophila subsp. ATCC 33152 bacterium, which suggests that this particular bacterium is more resistant to the effects of essential oils than the other two. Discussion and conclusion: During the research, we found that tea tree essential oil has the highest efficacy against biofilm formation and has antibacterial properties. Its active substances have been shown to have a positive effect on the prevention of biofilm formation. Development in the field of green chemistry represents a promising alternative to conventional methods of inhibiting the growth and development of biofilms, as further in-depth research could help reduce the use of conventional methods and, consequently, reduce microbial resistance and excessive use of conventional antimicrobial agents. Further research in this field would be necessary to determine the efficacy of the active components on different bacterial strains, together with the potential for synergistic activity of different essential oils.

• Ključne besede: master's theses, sanitary engineering, Legionella pneumophila, biofilms, legionellosis, antibacterial activity of natural substances