Utjecaj eteričnog ulja biljne vrste Micromeria thymifolia (Scop.) Fritsch i pulegona na proizvodnju pigmenta piocijanina bakterije Pseudomonas aeruginosa PAO1

master's thesis

• Title (english): Effect of Micromeria thymifolia (Scop.) Fritsch essential oil and pulegone on production of pyocyanin by Pseudomonas aeruginosa PAO1
• Author: Zrinka Tolić
• Mentor: Gordana Maravić Vlahoviček (mentor)
• Committee member: Gordana Maravić Vlahoviček (predsjednik povjerenstva)
• Committee member: Maja Šegvić Klarić (član povjerenstva)
• Committee member: Maja Bival Štefan (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of biochemistry and molecular biology); Zagreb
• Defense date and country: 2022-06-29, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Pseudomonas aeruginosa je oportunistički patogen koji dovodi do infekcija najčešće imunokompromitiranih osoba. Smatra se klinički najznačajnijom vrstom unutar roda Pseudomonas. Sposobnost stvaranja velikog broja strukturnih i sekrecijskih faktora virulencije kao i formiranje biofilma otežava liječenje infekcija P. aeruginosa. Sve veći razvoj bakterijske rezistencije kod P. aeruginosa, zbog neracionalne primjene antibiotika, dovodi do potrebe za istraživanjem alternativnih mogućnosti liječenja. Jedna od takvih mogućnosti je primjena eteričnih ulja. To su aromatične, hlapljive otopine kompleksnog sastava koje posjeduju antimikrobno djelovanje. U ovom radu ispitan je učinak eteričnog ulja vrste Micromeria thymifolia (Scop.) Fritsch i njegove glavne komponente pulegona u koncentracijama od 0,5 mg/mL na rast planktonskih stanica i proizvodnju sekrecijskog faktora virulencije piocijanina kod P. aeruginosa PAO1. Osim njihovog pojedinačnog učinka ispitivan je i potencijalni sinergistički učinak s aminoglikozidnim antibiotikom tobramicinom u subinihibitornoj koncentraciji 0,5 mg/L. Istraživanje učinka na rast planktonskih stanica P. aeruginosa PAO1 provedeno je spektrofotometrijskim mjerenjem optičke gustoće pri 600 nm. Eterično ulje mikromerije i pulegon pokazali su inhibitorni učinak na rast planktonskih stanica. Eterično ulje mikromerije pokazalo je i sinergistički učinak s tobramicinom pojačavajući njegovo djelovanje. Kombinacija pulegona i tobramicina nije dovela do pojave značajnog sinergizma u inhibiciji rasta planktonskih stanica P. aeruginosa PAO1. Ispitivanje učinka na proizvodnju piocijanina provedeno je spektrofotometrijskim mjerenjem ekstrahiranog piocijanina pri 520 nm. Eterično ulje mikromerije pokazalo je inhibitorni učinak, dok sami pulegon nije. Ispitivanja međudjelovanja tobramicina s eteričnim uljem i pulegonom pokazala su njihov antagonistički učinak koji je doveo do smanjenja djelovanja tobramicina. Rezultati ovog rada pridonose boljem razumijevanju kompleksnosti i antimikrobnog potencijala eteričnih ulja.

Abstract (english)

Pseudomonas aeruginosa is an opportunistic pathogen that most commonly leads to infections of immunocompromised individuals. It is considered to be the most clinically significant species within the genus Pseudomonas. The ability to produce a large number of structural and secretory virulence factors and to form biofilm complicates the treatment of P. aeruginosa infections. There is a great need to explore alternative treatment options because of the increase in development of bacterial resistance in P. aeruginosa, due to the irrational use of antibiotics. One of these alternative options is the use of essential oils. These are aromatic, volatile solutions of complex composition that possess antimicrobial activity. This study investigated the effect of Micromeria thymifolia (Scop.) Fritsch essential oil and its component pulegon in concentrations of 0,5 mg/mL on planktonic cell growth and production of virulence factor pyocyanin in P. aeruginosa PAO1. In addition to their individual effect, a potential synergistic effect with the aminoglycoside antibiotic tobramycin in subinhibitory concentration of 0,5 mg/L was also investigated. The effect on the planktonic growth of P. aeruginosa PAO1 cells was measured spectrophotometrically at 600 nm. Micromeria essential oil and pulegon used in concentration of 0,5 mg/mL showed an inhibitory effect on planktonic cell growth. Micromeria essential oil also showed a synergistic effect with tobramycin by enhancing its effect on growth of P. aeruginosa PAO1 plankton cells. The combination of pulegone and tobramycin did not lead to significant synergism. The effect on production of pyocyanin by P. aeruginosa PAO1 was investigated by spectrophotometric measurements of extracted pyocyanin at 520 nm. Micromeria essential oil showed an inhibitory effect, while pulegon did not. Interaction of tobramycin with essential oil and pulegon showed their antagonistic effect leading to a decrease in the activity of tobramycin. The results of this work contribute to a better understanding of the complexity and antimicrobial potential of essential oils.

• Keywords: Pseudomonas aeruginosa; Micromeria thymifolia (Scop.) Fritsch; pulegon; tobramicin; eterično ulje; piocijanin
• Keywords (english): Pseudomonas aeruginosa; essential oil; Micromeria thymifolia (Scop.) Fritsch; pulegone; tobramycin; pyocyanin
• Language: croatian
• URN:NBN: urn:nbn:hr:163:514349
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-07-26 12:24:37