| Abstract | Razvojem civilizacije i industrije povećava se i broj i količina onečišćujućih tvari u okolišu. Prisutnost onečišćujućih tvari u okolišu može se odrediti analizom uzoraka vode, tla, zraka i biote. Praćenje onečišćujućih tvari ključno je za razumijevanje njihovih izvora, putanja i učinaka na okoliš i ono pomaže u donošenju regulacija i strategija za smanjenje njihovog štetnog učinka. Ključnu ulogu u procjeni utjecaja onečišćujućih tvari na okoliš imaju testovi ekotoksičnosti. Oni ispituju kako različite tvari, uključujući industrijske kemikalije, pesticide i farmaceutske proizvode, utječu na ekosustave i organizme prisutne u njima. Uobičajene metode testova ekotoksičnosti su laboratorijski testovi na bakterijama, algama, vodenim beskralježnjacima i ribama, kojima se utvrđuje toksičnost, bioakumulacija i dugoročni učinci na populacije i ekosustave. Ekotoksičnost rodanida, odnosno tiocijanata, u ovom radu ispitana je primjenom bakterijske kulture Pseudomonas putida i mikroalge Chlorella sp. Za ispitivanje ekotoksičnosti rodanida pripremljeno je šest različitih koncentracija rodanida, koje su iznosile: γR1 = 1 mg L^-1, γR2 = 10 mg L^-1, γR3 = 25 mg L^-1, γR4 = 50 mg L^-1,
γR5 = 75 mg L^-1, γR6 = 100 mg L^-1. Kao mjerilo utjecaja rodanida na navedene mikroorganizme određivana je CFU vrijednost, odnosno broj živih stanica mikroorganizama tijekom 72 sata izlaganja i određivani su postotci inhibicije rasta navedene bakterijske kulture i mikroalge. U slučaju bakterijske kulture Pseudomonas putida, najveći postotak inhibicije nakon 72 sata izlaganja iznosio je 59,17 %, dok je kod mikroalge Chlorella sp. najveći postotak inhibicije iznosio 71,43 %. Dobiveni podaci pokazuju da mikroalga Chlorella sp. pokazuje veću osjetljivost na rodanide od bakterijske kulture Pseudomonas putida. |
| Abstract (english) | Along with the development of civilization and industry, the number and amount of pollutants in the environment increases. The presence of pollutants in the environment can be determined by analyzing samples of water, soil, air and biomes. Monitoring of pollutants is essential to understand their sources, pathways and effects on the environment and it helps to formulate regulation and strategy to reduce their harmful effect. Ecotoxicity tests play a key role in assessing the impact of pollutants on the environment. They examine how various substances, including industrial chemicals, pesticides and pharmaceuticals, affect ecosystems and the organisms present in them. Common methods of ecotoxicity tests are laboratory tests on bacteria, algae, aquatic invertebrates and fish, which determine toxicity, bioaccumulation and long-term effects on populations and ecosystems. In this paper, the ecotoxicity of rhodanide, or thiocyanate, was tested using the bacterial culture of Pseudomonas putida and the microalgae Chlorella sp. For testing the ecotoxicity of rhodanide, six different concentrations of rhodanide were prepared and applied, which were: γR1 = 1 mg L^-1, γR2 = 10 mg L^-1, γR3 = 25 mg L^-1, γR4 = 50 mg L^-1, γR5 = 75 mg L^-1, γR6 = 100 mg L^-1. As a measure of the effect of rhodanide on the mentioned microorganisms, the CFU value, i.e. the number of live cells of microorganisms during
72 hours of exposure, was determined, and the percentages of inhibition of the growth of the mentioned bacterial culture and microalgae were determined. In the case of the bacterial culture Pseudomonas putida, the highest percentage of inhibition after 72 hours of exposure was 59,17 %, while in the case of the microalgae Chlorella sp. the highest percentage of inhibition was 71,43 %. The obtained data show that the microalgae Chlorella sp. shows greater sensitivity to rhodanides than the bacterial culture of Pseudomonas putida. |
