20.500.12556/RUL-129152 Kvantifikacija biofilma na mikroplastiki Quantification of biofilm on microplastics Plastika je postala nepogrešljiv material v našem življenju. Tempo, ki ga diktira svetovna proizvodnja presega naše sposobnosti za odgovorno ravnanje s plastičnimi odpadki, ki pri tem nastajajo. Tako vsakodnevno v naravo zaidejo ogromne količine plastike. Ta razpada na manjše delce, ki jim pravimo mikroplastika. Mikroplastika je v naravnem okolju podvržena številnim fizikalnim in kemijskim dejavnikom, poleg tega pa tako prihaja v stik s prisotnimi mikroorganizmi v okolju. Le-ti na površini mikroplastike tvorijo biofilm, ki še dodatno vpliva na njeno obnašanje v okolju. Delcem, na katerih se naselijo mikroorganizmi, se poveča gostota, kar vpliva na njihovo porazdelitev v vodnem okolju, ter biodostopnost za druge organizme. Prisotnost biofilma vpliva tudi na kroženje nutrientov, strupenost in interakcije z onesnaževali, ki so prisotni v vodi. V okviru eksperimentalnega dela diplomske naloge smo mikroplastiko izpostavili površinski vodi iz okolja in vrednotili razvoj biofilma na njeni površini ter spremembe v lastnostih mikroplastike. Ugotovili smo, da se na njej hitro razvija biofilm. Aktivnost biofilma smo dokazali z določanjem aktivnosti encimov ureaz, fotosintetskega pigmenta klorofila in ekstrahiranih zunajceličnih polimernih snovi. Mikroplastiki se je v 12 tednih izpostavljenosti površinski vodi povečala gostota, poleg tega pa je bil biofilm odgovoren tudi za njeno aglomeracijo. Plastic has become an indispensable material in our lives. The pace dictated by global production exceeds our ability to responsibly handle generated plastic waste. Therefore, enormous amounts of plastics end up in our environment every day, where they break down into smaller particles called microplastics. By entering the environment, microplastics are subject to a number of physical and chemical factors. They also encounter microorganisms, which form a biofilm on a particle surface and further affect behavior of microplastics. The density of particles then increases after biofouling, affecting their distribution in the aquatic environment and their bioavailability to other organisms. The presence of biofilm also affects nutrient flow, toxicity, and interactions with contaminants present in water. In experimental part of the thesis, we exposed microplastics to surface water and evaluated the development of biofilm on its surface, as well as changes in the properties of microplastics. Results showed that living microorganisms can easily colonized microplastics. The viability of the biofilm was demonstrated by the measurement of activity of the urease enzymes, by the determination of the photosynthetic pigment (i.e. chlorophyll) and by analysis of extracted extracellular polymeric substances. After 12 weeks of aging in surface water, the density of microplastics increased and particles started to agglomerate as a consequence of biofilm formation. biofilm mikroplastika vodni ekosistem aquatic ecosystems biofilm microplastics true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2021-08-27 12:00:00 2021-08-27 12:00:00 2022-09-08 04:06:54 0000-00-00 00:00:00 2021 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 11525 75493891 Turk_Katja_-_Kvantifikacija_biofilma_na_mikroplastiki.pdf Turk_Katja_-_Kvantifikacija_biofilma_na_mikroplastiki.pdf 1 B9B137DBC45E900D6A871D1ED8C96F07 6938155f1a722f5c9879fbd3dce7c8d166d621131b4660758ca79547617b1a0d 52762d4f-071d-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=146089 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0