Microplastics in the Marine Environment of the Adriatic Sea

Plastika se zbog svoje široke uporabe može naći u svim dijelovima okoliša, gdje štetno utječe na različite sastavnice okoliša, a toksični spojevi koje adsorbira prenose se kroz hranidbene lance te s vremenom dolaze do čovjeka. Odabrana istraživanja u ovom radu usredotočena su na karakterizaciju i kvantifikaciju mikroplastike pronađene u Jadranskom moru kao i na toksičnost mikroplastike. Istraživanja su pokazala da je najviše mikroplastike detektirano u području Sjevernog Jadrana. Provedena ispitivanja ekotoksičnosti mikroplastike primjenom testa s algama ukazuju na to da mikroplastika uzrokuje smanjenje brzine rasta i kretanja algi, obavljanje fotosinteze, fizičke deformacije te dolazi do smanjenja plodnosti i promjena u metaboličkim ciklusima. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.The widespread use of plastics has led to the accumulation of plastics in all parts of the environment where it adversely affects the ecosystem. Plastic pollution has the biggest impact on the marine ecosystems which assimilate about 12.7 million tons of plastic yearly. Because of incomplete degradation, plastic in marine environment is accumulated in the form of large clusters and microplastic. Microplastic has a harmful impact on marine organisms due to the accumulation of toxic compounds adsorbed on its particles, which could be passed through the food chain and eventually to humans. Certain researches discussed in this paper are focused on the characterization and quantification of microplastic found in the Adriatic Sea. This work is licensed under a Creative Commons Attribution 4.0 International License

Dvojni lijekovi primakina i nesteroidnih protuupalnih lijekova: Sinteza, hvatanje slobodnih radikala, antioksidativno djelovanje i keliranje Fe2+ iona

Novel primaquine conjugates with non-steroidal anti-inflammatory drugs (PQ-NSAIDs, 4a-h) were prepared, fully chemically characterized and screened for radical scavenging and antioxidant activities. The synthetic procedure leading to twin drugs 4a-h involved two steps: i) preparation of NSAID benzotriazolides 3a-h from the corresponding NSAID (ibuprofen, ketoprofen, fenoprofen, ketoprofen hydroxy and methylene analogues, diclofenac or indomethacin) and benzotriazole carboxylic acid chloride (BtCOCl, 1), ii) reaction of intermediates 3a-h with PQ. The prepared PQ-NSAIDs exerted moderate activities in the DPPH free radical test and -carotene-linoleic acid assay. Moreover, ketoprofen derivatives 4d and 4b demonstrated a notable Fe2+ chelating ability as well. On the other hand, negligible antiproliferative and antituberculotic effects of conjugates 4a-h were observed.U radu je opisana sinteza novih konjugata primakina s nesteroidnim protuupalnim lijekovima (PQ-NSAIDs, 4a-h), njihova potpuna karakterizacija te testiranje sposobnosti hvatanja slobodnih radikala i antioksidativnog djelovanja. Sintetski postupak za pripravu dvojnih lijekova 4a-h uključuje dva koraka: i) pripravu NSAID-benzotriazolida 3a-h iz odgovarajućih nesteroidnih protuupalnih lijekova (ibuprofena, ketoprofena, fenoprofena, hidroksi i metilenskih analoga ketoprofena, diklofenaka i indometacina) i klorida 1-benzotriazol karboksilne kiseline (BtCOCl, 1), ii) reakciju intermedijera 3a-h s primakinom. Novi PQ-NSAID konjugati pokazuju umjerenu sposobnost hvatanja slobodnih radikala u DPPH testu te umjereno antioksidativno djelovanje u pokusu s -karotenom i linoleinskom kiselinom. Osim toga, derivati ketoprofena 4d i 4b imaju primjetnu sposobnost keliranja Fe2+ iona. Svi konjugati 4a-h pokazuju vrlo slabo antiproliferativno i antituberkulotsko djelovanje

Assessment of the Influence of Size and Concentration on the Ecotoxicity of Microplastics to Microalgae <i>Scenedesmus</i> sp., Bacterium <i>Pseudomonas putida</i> and Yeast <i>Saccharomyces cerevisiae</i>

The harmful effects of microplastics are not yet fully revealed. This study tested harmful effects of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET) microplastics were tested. Growth inhibition tests were conducted using three microorganisms with different characteristics: Scenedesmus sp., Pseudomonas putida, and Saccharomyces cerevisiae. The growth inhibition test with Scenedesmus sp. is relatively widely used, while the tests with Pseudomonas putida and Saccharomyces cerevisiae were, to our knowledge, applied to microplastics for the first time. The influence of concentration and size of microplastic particles, in the range of 50–1000 mg/L and 200–600 µm, was tested. Determined inhibitions on all three microorganisms confirmed the hazardous potential of the microplastics used. Modeling of the inhibition surface showed the increase in harmfulness with increasing concentration of the microplastics. Particle size showed no effect for Scenedesmus with PE, PP and PET, Pseudomonas putida with PS, and Saccharomyces cerevisiae with PP. In the remaining cases, higher inhibitions followed a decrease in particle size. The exception was Scenedesmus sp. with PS, where the lowest inhibitions were obtained at 400 µm. Finally, among the applied tests, the test with Saccharomyces cerevisiae proved to be the most sensitive to microplastics

Ružička days : International conference 18th Ružička Days “Today Science – Tomorrow Industry” : Proceedings

Proceedings contains articles presented at Conference divided into sections: chemical analysis and synthesis, chemical and biochemical engineering, food technology and biotechnology, medical chemistry and pharmacy, environmental protection and meeting of young chemists

Ružička days : International conference 17th Ružička Days “Today Science – Tomorrow Industry” : Proceedings

In front of you are the Proceedings of the International Conference 17th Ružička days: „Today Science – Tomorrow Industry“ that was held in Vukovar, Croatia at September 19-21, 2018. The main goal of this interdisciplinary conference is to promote excellence in science and engineering as well as application of up-to-date research results and technological achievements in industry. In its fifth issue (2011, 2013, 2015, 2017, 2019) the Proceedings continues with publishing of quality scientific and professional full papers in sections Chemical Analysis and Synthesis (2), Chemical and Biochemical Engineering (3), Food Technology and Biotechnology (4), Medical Chemistry and Pharmacy (2), Environmental Protection (9) and Meeting of Young Chemists (4). All the papers were thoroughly reviewed from respectable evaluators, to whom we express our gratitude. We are also thankful to all the authors and participants of the Ružička days, and to all that support and contribute in its organization; especially our international coorganizers EuCheMS, EFFoST and EHEDG, the members of organizing and scientific committee, plenary and invited lecturers, sponsors, and of course our highly skilled and committed associates, which put a lot of effort in preparation of this book

Ružička days : International conference 19th Ružička Days “Today Science – Tomorrow Industry” : Proceedings

Dear colleagues, we are extremely honoured to present to you the Proceedings of the international conference 19th Ružička Days, which was successfully held on September 21–23, 2022, in Vukovar, Croatia, in the hometown town of our famous Croatian scientist and first Nobel laureate, professor Leopold (Lavoslav) Ružička. The main goals of the Conference were to promote excellence, originality and innovation of interdisciplinary scientific research as well as the practical application of the obtained results through collaboration with industry, emphasizing thus the recognizable slogan of the Ružička Days conference: "Today Science – Tomorrow Industry". In addition, the Conference gave the opportunity for meetings, exchanging the ideas, opinions, experiences and cooperation among participants from different working surroundings. It is also important to point out that since 2008, within the international conference Ružička Days, Meeting of Young Chemists has also been held, where high school students, with the help of their mentors, present papers in the field of chemistry, with the aim to direct students and young people to the technical and natural sciences, especially chemistry. In its seventh issue (2011, 2013, 2015, 2017, 2019, 2021) the Proceedings publishes scientific and professional full papers of high quality in the following sections: Chemical analysis and synthesis (10), Chemical and biochemical engineering (3), Food technology and biotechnology (4), Chemistry in agriculture and forestry (1), Environmental protection (9) and 8th Meeting of Young Chemists (3). Full-length papers were subjected to an international review procedure done by eminent experts from the corresponding fields, to whom we express our gratitude, but they were not subjected to linguistic proofreading. On behalf of the Scientific and Organizing Committee of the 19th Ružička Days we cordially thank all the authors, reviewers, participants, lecturers, organizers, especially the international organizers EuCheMS and EHEDG, auspices and sponsors, and all the others who, in any way, supported the Conference and contributed to the preparation of the Proceedings, especially to our highly skilled and committed associates, who have put a lot of effort in the preparation of these Proceedings. At the very end, special thanks to our young, future scientists and their mentors who are faithful participants of the Meeting of Young Chemists of the Ružička Days conference. Enjoy the extremely interesting scientific and professional papers contained in these Proceedings, until the next 20th jubilee of Ružička Days in 2024! We are looking forward to meeting you again in Vukovar! Yours sincerely, Chief Editors Jurislav Babić Vesna Ocelić Bulatović Dajana Kučić Grgi