20.500.12556/DiRROS-19961 Preliminary experiments into colonization of microorganisms from activated sludge on different types of plastics Preliminarni poskusi kolonizacije različnih tipov plastike z mikroorganizmi iz aktivnega blata The presence of plastics in the environment is currently one of the most pressing global environmental problems. Microorganisms start to form biofilms on plastic surfaces when they first come in contact with the biosphere; however, these interactions and processes are little understood, especially in freshwaters. This study aimed to better understand the colonization process of microorganisms from activated sludge on plastic materials exhibiting different surface characteristics. We inoculated synthetic fabric (PET), water bottles (PET), and plastic bags for packing vegetables and fruits (HDPE) with microorganisms from activated sludge. Mixtures of plastics and activated sludge, as well as the control, were incubated at 22-24°C in Bushnell Haas (BH) liquid medium and shaken at 120 rpm for two months. The mixtures were sub-sampled weekly and seeded into fresh BH medium with test plastic materials to avoid feeding microorganisms on dead biomass. The colonization was followed by measuring optical density (OD600) of liquid medium, by measurements of isotopic composition of carbon (δ13C) in untreated and treated plastic materials and, with in-specting the plastics surface with scanning electron microscopy (SEM). Overall, the study confirmed differences between colonizing microorganisms on different plastic material when comparing SEM micrographs of materials from the flasks inoculated with activated sludge. The texture of the HDPE bag changed during the experiment in both, control and inoculated flasks, but it is not clear whether the observed changes were due to abiotic or biotic factors. We concluded that microorganisms from activated sludge are capable of colonizing both PET and HDPE materials, and biofilm formation is most probably influenced by the chemical composition of plastics and their surface characteristics. biofilm plastics SEM isotopic composition of carbon co-cultivation UV sterilization biofilm plastika SEM izotopska sestava ogljika ko-kultivacija UV sterilizacija true false true Angleški jezik Slovenski jezik Neznano 2024-07-31 11:50:49 2024-07-31 11:50:49 2024-08-02 03:39:35 0000-00-00 00:00:00 2020 0 0 str. 45-61 no. 1 Vol. 63 2020 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2020-07-01 502/504 1408-3671 10.14720/abs.63.1.15914 26885379 https://doi.org/10.14720/abs.63.1.15914 1 a1585037-4f11-11ef-b487-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=27706 https://journals.uni-lj.si/abs/article/view/15914 1 a332d17b-4f11-11ef-b487-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=27707 RAZ_Matjasic_Tjasa_2020.pdf RAZ_Matjasic_Tjasa_2020.pdf 1 8A9BC20DE17DDAA8A5E975E81466A61B f61c93f7de7c0c1c99d22bea4397135930797c49f55f29a8e73f05659a417038 0396fc20-4f12-11ef-b487-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=27708 Nacionalni inštitut za biologijo 0 0 0