Utjecaj čestica nanosrebra na rast i pojavu oksidacijskog stresa u korjenčićima luka (Allium cepa L.)

master's thesis

• Title (english): Influence of silver nanoparticles on growth and appearance of oxidative stress in Allium cepa L. roots
• Author: Anita Milošić
• Mentor: Biljana Balen (mentor)
• Committee member: Biljana Balen (predsjednik povjerenstva)
• Committee member: Mirta Tkalec (član povjerenstva)
• Committee member: Martina Šeruga Musić (član povjerenstva)
• Committee member: Željka Vidaković-Cifrek (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2014-07-23, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Nanočestice su trenutno vrlo živo područje istraživanja zahvaljujući svojim jedinstvenim električnim, kemijskim i fizičkim svojstvima, a zbog sve češće tržišne uporabe postavlja se pitanje koliko su štetne za žive organizme i okoliš. U ovom radu istražen je utjecaj nanočestica srebra (AgNP) na rast i pojavu oksidacijskog stresa u korjenčićima luka. Uspoređena je toksičnost primijenjenih koncentracija (25, 50, 75, 100 i 500 μM) AgNP s učinkom ionskog srebra (AgNO3) istih koncentracija. Također je uspoređen učinak nanosrebra stabiliziranog s tri različita organska omotača (AgNP-citrat, AgNP-PVP i AgNP-CTAB). Rezultati su pokazali da je ionsko srebro pri svim ispitanim koncentracijama jače inhibiralo rast korjenčića luka od nanosrebra. Sadržaj malondialdehida (MDA), kao pokazatelja oksidacijskog stresa, bio je povećan nakon tretmana ionskim srebrom i nanosrebrom AgNP-CTAB, a smanjen nakon tretmana nanosrebrom AgNP-citrat i AgNP-PVP. Sadržaj proteinskih karbonila bio je smanjen nakon tretmana ionskim srebrom, dok je samo nanosrebro AgNP-citrat pokazalo smanjenje sadržaja karbonila kako su rasle ispitane koncentracije. Tretmani nanosrebrom AgNP-PVP i AgNP-CTAB nisu doveli do promjene u sadržaju karbonila u odnosu na kontrolu. Sva tri ispitana antioksidacijska enzima (katalaza, pirogalol peroksidaza i askorbat peroksidaza) pokazala su promjene u aktivnosti, koje su posljedica izlaganja korjenčića ionskom srebru i nanosrebru.

Abstract (english)

Nanoparticles became the subject of interest in science thanks to their unique electric, chemical and physical properties. Since they are commonly used in consumer products, there is a need to investigate their possible negative effect on living organisms and environment. The present study investigated the effect of silver nanoparticles (AgNP) on growth and appearance of oxidative stress in A. cepa roots. The toxicity of AgNPs and AgNO3 applied at the same concentrations (25, 50, 75, 100 and 500 μM) was also compared. The effect of three different organic coatings, AgNP-citrate, AgNP-PVP and AgNP-CTAB, was additionally analysed. The results showed that ionic silver inhibited root growth more strongly than AgNP. Malondialdehyde (MDA) content, as a parameter of oxidative stress, was increased after treatment with ionic silver and nanosilver AgNP-CTAB and decreased after treatment with nanosilver AgNP-citrate and AgNP-PVP. Protein carbonyl content was also decreased after treatment with ionic silver and AgNP-citrate, and no changes were observed after AgNP-PVP and AgNP-CTAB treatment. All of three investigated antioxidant enzymes (CAT, PPX, APX) showed changes in activity that could be a consequence of root exposure to ionic and nanosilver.

• Keywords: Allium cepa; antioksidacijski enzimi; lipidna peroksidacija; nanočestice srebra; oksidacijski stres; proteinski karbonili
• Keywords (english): Allium cepa; antioxidative enzymes; lipid peroxidation; oxidative stress; protein carbonyls; silver nanoparticles
• Language: croatian
• URN:NBN: urn:nbn:hr:217:578998
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra molekularne biologije (magistar/magistra molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-04-24 11:43:24