Toksičnost ekstrakata invazivnih tropskih algi roda Caulerpa

master's thesis

• Title (english): Toxicity of extracts derived from invasive tropical algae from the genus Caulerpa
• Author: Josip Kerkez
• Mentor: Tvrtko Smital (mentor)
• Mentor: Sandra Radić Brkanac (mentor)
• Committee member: Sandra Radić Brkanac (predsjednik povjerenstva)
• Committee member: Blanka Cvetko Tešović (član povjerenstva)
• Committee member: Alan Moro (član povjerenstva)
• Committee member: Goran Klobučar (član povjerenstva)
• Committee member: Danijel Orešić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2019-07-19, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Invazivno širenje morskih algi roda Caulerpa ima štetan učinak na veliki broj autohtonih vrsta i dovodi do drastičnog smanjenja bioraznolikosti, osobito suzbijanjem rasta bentoskih zajednica morskih cvjetnica. Pored tjelesne građe i načina razmnožavanja, svoju sposobnost širenja vrste algi roda Caulerpa vjerojatno postižu i odbijanjem ostalih morskih vrsta proizvodnjom toksičnih sekundarnih metabolita. Primjerice, kaulerpenin je acetilenski seskviterpen, koji je prisutan u značajnim količinama kod obje invazivne vrste roda Caulerpa koje nalazimo u Mediteranu, pa tako i u Jadranskom moru. Ispitivanjem toksičnosti ekstrakata ovih invazivnih vrsta algi korištenjem različitih biotestova, mogude je testirati ovu hipotezu te procijeniti njihovu potencijalnu štetnost za ostale morske vrste.
Cilj ovog istraživanja je odrediti toksični učinak ekstrakata uzoraka algi roda Caulerpa prisutnih u Jadranskom moru testiranjem njihove akutne i kronične toksičnosti te utjecaja na stanični detoksikacijski sustav faze I. Akutna citotoksičnost testirana je MTT ((3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolijev bromid)) testom, kolorimetrijskom metodom kojom se određivalo preživljavanje ribljih PLHC -1/wt stanica nakon izlaganja ekstraktima. Kronična toksičnost ekstrakata određena je AlgaeTox testom kojim se određuje inhibicija rasta jednostaničnih algi vrste Scenedesmus subspicatus. Za određivanje indukcije staničnog detoksikacijskog sustava faze I korišten je EROD (etoksirezorufin – O – deetilaza) test, pomodu kojeg se mjeri indukcija aktivnosti CYP1A1 detoksikacijskog enzima. Rezultati dobiveni opisanim biotestovima su pokazali jasan toksični učinak na stanice u prisutstvu ekstrakata obiju testiranih vrsta algi roda Caulerpa.

Abstract (english)

The spread of invasive marine algae from the genus Caulerpa has a harmful effect on a large number of autochthonous species and causes a drastic reduction of biodiversity, especially by repressing benthic seagrass communities. Aside from its basic physiology characteristics and reproduction strategies, the genus Caulerpa enhances its invasive potential by producing toxic secondary metabolites. The main example of these compounds is caulerpenyne, a terpenoid sesquiterpene present in significant amounts in both of the sampled invasive species found in the Adriatic and Mediteranean Sea. Analysing the toxicity of extracts prepared from these invasive alge species through multpile toxicity assays it is possible to test their potential harmfulness to other marine species.
The major goal of this study was to determine (eco)toxic effects of extracts derived from Caulerpa species present in Adriatic by testing their acute and chronic toxicity potential and effect on the phase I cellular detoxification system. Acute toxicity was determined by the colorimetric MTT ((3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)) assay used to determine viability of fish PLHC -1/wt cells upon exposure to algal extracts. Chronic toxicity was analysed by the AlgaeTox assay to determine the growth inhibition of the unicellular algae Scenedesmus subspicatus. Effects of the algal extracts on the phase I of cellular detoxification was determined by the EROD (ethoxyresorufine - O - deethylase) assay used to measure induction of the CYP1A1 detoxification enzyme. The results from all of the toxicity assays clearly revealed toxicity of algal extracts derived from both Caulerpa species.

• Keywords: inhibicija rasta algi; indukcija CYP1A1 monooksigenaza; sekundarni metaboliti; EROD biotest; MTT biotest; AlgaTox biotest
• Keywords (english): algal growth inhibition; CYP1A1 monooxygenase induction; secondary metabolites; cytotoxicity; EROD assay; MTT assay; AlgaTox assay
• Language: croatian
• URN:NBN: urn:nbn:hr:217:904447
• Study programme: Title: Enviromental Sciences; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra struke znanosti o okolišu (magistar/magistra struke znanosti o okolišu)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-09-17 11:43:02