Tvorba mikotoksina aspergila u uvjetima ex vivo

master's thesis

• Title (english): Mycotoxin production by Aspergillus species under ex vivo conditions
• Author: Ana Akrap
• Mentor: Maja Šegvić Klarić (mentor)
• Committee member: Maja Šegvić Klarić (predsjednik povjerenstva)
• Committee member: Ana-Marija Domijan (član povjerenstva)
• Committee member: Irena Brčić Karačonji (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of microbiology); Zagreb
• Defense date and country: 2019-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Plijesni roda Aspergillus predstavljaju prijetnju čovjekovom zdravlju jer se inhalacija njihovih konidija i dijelova micelija povezuje s nizom različitih patoloških stanja respiratornog sustava. Aspergili su producenti velikog broja mikotoksina, sekundarnih metabolita koji djeluju karcinogeno, hepatotoksično, nefrotoksično i imunotoksično, a mogli bi biti odgovorni za ezgarcebaciju simpetoma
budući da su detektirani i u tjelesnim tekućinama oboljelih od aspergiloza. Kako bi se ispitala uloga
mikotoksina u virulenciji aspergila, odnosno sposobnost njihove biosinteze in situ, osam vrsta iz
sekcija Circumdati, Flavi, Nigri i Versicolores inokulirano je na Brain Heart Agar (BHA), hranjivu
podlogu koja oponaša uvjete u ljudskim tkivima, uz dodatak saharoze u koncentraciji od 4 g/L pri
temperaturama od 25°C i 37°C. Ekstrakti mikotoksina iz čistih kultura plijesni analizirani su vezanim sustavom tekućinske kromatografije visoke djelotvornosti i masene spektrometrije. Od osam
izolata, tek su tri formirala kolonije pri 37°C, no niti jedan nije producirao mikotoksine na čovjekovoj tjelesnoj temperaturi zbog čega je malo vjerojatno da su aflatoksin B1, fumonizin B2, okratoksin
A, sterigmatocistin i 5-metoksisterigmatocistin faktori virulencije aspergila.

Abstract (english)

Aspergillus species represent a threat to the human health due to the association of the inhalation of
their conidia and mycellium parts with several pathological conditions of the respiratory system. They
produce a large number of mycotoxins, secondary metabolites with carcinogenic, hepatotoxic,
nephrotoxic and immunotoxic effects, that could be responsible for exacerbation of symptoms of
aspergillosis as they have been detected in the body fluids of patients suffering from this group of
diseases. In order to determine the role of mycotoxins in the Aspergillus virulence, eight species from
the sections Circumdati, Flavi, Nigri and Versicolores was inoculated on the brain heart infusion agar
(BHA), growth medium which imitates human tissues, with the addition of 4 g/L succrose at 25 and
37°C. Analysis of the mycotoxin extracts was performed with a coupled high performance liquid
chromatography-mass spectrometry system. Out of eight isolates, only three formed colonies at 37°C,
but not one produced the expected mycotoxins at the human body temperature. This leads to conclusion that aflatoxin B1, fumonisin B2, ochratoxin A, sterigmatocystin and 5-methoxysterigmatocystin
are not virulence factors of the Aspergillus species.

• Keywords: BHA; aflatoksini; fumonizini; okratoksin A; sterigmatocistin; Circumdati; Flavi; Nigri; Versicolores
• Keywords (english): BHA; aflatoxins; fumonisins; ochratoxin A; sterigmatocystin; Circumdati; Flavi; Nigri; Versicolores
• Language: croatian
• URN:NBN: urn:nbn:hr:163:804849
• 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: 2020-02-21 15:52:53