MORFOLOŠKI, FIZIOLOŠKI I PROTEOMSKI ODGOVORI SLATKOVODNE ALGE Chlorella vulgaris NA IZLAGANJE NANOČESTICAMA SREBRA, BAKRA I POLISTIRENA

doctoral thesis

• Title (english): MORPHOLOGICAL, PHYSIOLOGICAL AND PROTEOMIC RESPONSES OF THE FRESHWATER ALGA Chlorella vulgaris EXPOSED TO SILVER, COPPER AND POLYSTYRENE NANOPARTICLES
• Author: Bruno komazec
• Mentor: Petra Peharec Štefanić (mentor)
• Committee member: Biljana Balen (predsjednik povjerenstva)
• Committee member: Mirta Tkalec (član povjerenstva)
• Committee member: Tea Mišić Radić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2024-06-20, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology
• Universal decimal classification (UDC): 57 - Biological sciences. Physical anthropology. Biodiversity

Abstract

Nanočestice srebra (AgNP), bakrovog(I) oksida (Cu2ONP) i bakrovog(II) oksida (CuONP) te polistirena imaju široku primjenu u komercijalnim proizvodima, zbog čega predstavljaju opasnost za različite ekosustave, uključujući i vodene. U ovom radu istražen je utjecaj AgNP stabiliziranih omotačima citrat i cetiltrimetilamonij bromid, CuONP i Cu2ONP te nanočestica polistirena bez funkcionalne skupine i s amino i karboksilnom skupinom na algu Chlorella vulgaris. Dodatno je analiziran utjecaj AgNO3 i CuSO4, kao srebra i bakra u ionskom obliku. Usporedba vrijednosti EC25 pokazala je da su tretmani s AgNP najtoksičniji za alge, što je vjerojatno posljedica njihove slabije aglomeracije u odnosu na nanočestice bakra i veće reaktivnosti u odnosu na nanočestice polistirena. Oba tipa AgNP kao i CuONP i Cu2ONP izazvali su oksidacijski stres, oštećenje strukture stanica i makromolekula te promjene u procesu fotosinteze, iako je najjači učinak na parametre fotosinteze i staničnu ultrastrukturu zabilježen nakon izlaganja nanočesticama polistirena, što se može pripisati njihovom velikom afinitetu vezanja na površinu stanice. Dobiveni rezultati pokazuju da površinski omotači, funkcionalne skupine i oksidacijska stanja imaju veliku ulogu u stabilnosti nanočestica, što posljedično utječe na njihovu toksičnost, dok se disocijacija iona s nanočestica metala pokazala kao ključni mehanizam njihove toksičnosti.

Abstract (english)

Silver (AgNP), copper(I) oxide (Cu2ONP) and copper(II) oxide (CuONP), and polystyrene nanoparticles are widely used in commercial products and therefore they pose a risk to various ecosystems, including aquatic ones. In this work, the influence of AgNPs stabilised with citrate and cetyltrimethylammonium bromide coatings, CuONP and Cu2ONP, and polystyrene nanoparticles without a functional group and with amino and carboxyl groups on the algae Chlorella vulgaris was investigated. The influence of AgNO3 and CuSO4, as silver and copper in ionic form, was additionally analysed. A comparison of EC25 values showed that AgNP treatments are the most toxic to algae, which is probably due to their weaker agglomeration compared to copper nanoparticles and higher reactivity compared to polystyrene nanoparticles. Both types of AgNP as well as CuONP and Cu2ONP caused oxidative stress, damage to the cell structure and the macromolecules, and changes in the photosynthetic process, although the strongest effect on photosynthesis parameters and cellular ultrastructure was recorded after treatment with polystyrene nanoparticles, which can be attributed to their high binding affinity to the cell surface. The obtained results show that surface coatings, functional groups and oxidation states have a major role in the stability of nanoparticles, which consequently affects their toxicity, while the dissociation of ions from metal nanoparticles proved to be a key mechanism of their toxicity.

• Keywords: zelena alga; stabilizirajući omotači; oksidacijska stanja; funkcionalne skupine; oksidacijski stres; fotosinteza; ekspresija proteina
• Keywords (english): green algae; stabilising coatings; oxidation states; functional groups; oxidative stress; photosynthesis; protein expression
• Language: croatian
• URN:NBN: urn:nbn:hr:217:252131
• Promotion: 2024
• Project: Number: IP-2018-01-5351; Title: Određivanje fizikalno-kemijskih svojstava i toksičnosti nanočestica srebra, bakra i plastike kao potencijalno štetnih novih materijala u obalnim vodama; Acronym: NANO-EMC2; Leader: Daniel Mark Lyons; Jurisdiction: Croatia; Funder: Hrvatska zaklada za znanost; Funding stream: Research Projects
• Study programme: Title: Doctoral study; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti u području prirodnih znanosti (doktor/doktorica znanosti u području prirodnih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-07-05 10:53:16