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Sinteza novih steroidnih jedinjenja od potencijalnog biomedicinskog značaja / Synthesis of new steroidal compounds of potentialbiomedical importanceNikolić Andrea 25 April 2014 (has links)
<p>Cilj ove doktorske disertacije je bila sinteza novih steroidnih 16,17-seko-16,17a-dinitrila polazeći od dehidroepiandrosterona (1), odnosno estrona (14). U androstanskoj seriji su izvršene modifikacije 16,17-seko-16,17a-dinitrila 12 u A i/ili B prstenu steroidnog jezgra, pri čemu novosintetizovana jedinjenja sadrže 4-en-3-on, 1,4-dien-3-on ili 1,4,6-trien-3-on sistem, kao i supstituente u položajima C-4, odnosno C-6 (6-metilen, 6-keto i 6-oksimino). U radu je takođe proučavan uticaj odabranih novosintetizovanih jedinjenja na proliferaciju sedam ćelijskih linija humanih tumora, dok je kao kontrola služila jedna zdrava humana ćelijska linija.</p> / <p>Starting from dehydroepiandrosterone (1) or estrone (14) new steroidal 16,17-seco-16,17a-dinitriles were synthesized. Modification of 16,17-seco-16,17a-dinitrile 12 afforded androstane derivatives containing 4-en-3-on, 1,4-dien-3-on or 1,4,6-trien-3-on system, with different substituents on position C-4 or C-6 (6-methylene, 6-keto i 6-oximino). Antiproliferative activity of some newly synthesized compounds were examined against seven human tumor cell lines, while healthy cells served as control.</p>
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Sinteza i antiproliferativna aktivnost novih D-homo i D-seko derivata androstana / Synthesis and antiproliferative activity of new D-homo and D-seco androstane derivativesSavić Marina P. 19 March 2013 (has links)
<p>U prvom delu ove doktorske disertacije je izvršena<br />sinteza novih derivata androstana sa D-laktonskom<br />funkcijom ili D-seko derivata, sa modifikacijama u Ai/<br />ili B-prstenovima. U drugom delu je ispitana<br />antiproliferativna aktivnost odabranih<br />novosintetizovanih jedinjenja prema humanim<br />tumorskim ćelijskim linijama (MCF-7, MDA-MB-231,<br />PC-3, HeLa, HT-29, K562) kao i prema zdravim<br />ćelijama fetalnih fibroblasta pluća (MRC-5).</p> / <p>In first part of this work was achieved synthesis of some new androstane derivatives with D-lactone function and new D-seco derivatives with modification in A and/or B rings. In the second part the antiproliferative activity of selected newly synthesized compounds by human carcinoma cell lines (MCF-7, MDA-MB-231, PC-3, HeLa, HT-29, K562) and the healthy cells of fetal lung fibroblasts (MRC-5 ) was examined.</p>
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Sinteza i biološka aktivnost 17-supstituisanih androstanskih derivata / Synthesis and biological activity of 17-substituted androstane derivativesAjduković Jovana 08 October 2013 (has links)
<p>U prvom delu ove doktorske disertacije je izvršena sinteza novih 17α-pikolil i 17(E)-pikoliniliden androstanskih derivata, sa modifikacijama u A- i/ili B-prstenovima. U drugom delu rada je ispitana antiproliferativna aktivnost odabranih novosintetizovanih jedinjenja prema humanim tumorskim ćelijskim linijama (MCF-7, MDA-MB-231, PC-3, HeLa, HT-29 i A549) kao i prema zdravim ćelijama fetalnih fibroblasta pluća (MRC-5).</p> / <p>In the first part of this dissertation, the synthesis of new 17α-picolyl and 17(E)-picolinylidene androstane derivatives with modifications in A and/or B rings, were presented. The second part of the work consisted on investigation of antiproliferative activity of selected newly synthesized compounds toward human carcinoma cell lines (MCF-7, MDA-MB-231, PC-3, HeLa, HT-29 and A549), as well as the healthy fetal lung fibroblasts (MRC-5).</p>
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Micelarna solubilizacija holesterola pomoću okso derivata žučnih kiselina / Micellar solubilization of cholesterol by oxo-derivatives of bile acidsFarkaš Zita 08 July 2015 (has links)
<p>Doktorska disertacija razmatra solubilizaciju holesterola pomoću okso derivata žučnih kiselina, upoređuje okso derivate žučnih kiselina sa hidroksi-derivatima istih u solubilizaciji holesterola i ispituje uticaj okso derivata na vijabilnost ćelijske membrane. Takođe, ispituje pKa vrednost različitih okso-derivata žučnih kiselina sa ciljem da se odredi kiselinska konstanta ovih slabih organskih kiselina. Cilj određivanja pKa vrednosti jeste determinacija rastvorljivosti žučnih kiselina. Kada se primenjuju oralno u raznim farmaceutsko-tehnološkim formulacijama, one se primenjuju u obliku soli, koje su rastvorne u vodi. Međutim, u kiseloj sredini želuca može doći do taloženja žučne kiseline i do daljeg sprečavanja delovanja soli žučne kiseline kao solubilizatora određenih farmacutski aktivnih supstanci. Doktorska disertacija ispituje i kritičnu micelarnu koncentraciju mešovitih micela natrijumovih soli 3 žučne kiseline (holne, deoksiholne i 7-oksodeoksiholne kiseline) i natrijum-dodecil-sulfata u različitim molskim udelima na temperaturama od 0 do 50°C pomoću spektrofluorifotometra pirenskom metodom.</p> / <p>The PhD thesis discusses solubilization of cholesterol by using oxo derivatives of bile acids and compares it with the hydroxy-derivatives of the same in the solubilization of cholesterol, and examines the impact of the oxo derivatives to the viability of the cell membrane. Also, the pKa value of different tested oxo-derivatives of bile acids is determined. The aim of determining the pKa values is to determine the solubility of bile acids. When administered orally in various pharmaceutical-technological formulations, they are applied in the form of salts, that are soluble in water. However, the acidic medium of the stomach may cause precipitation of a bile salt and further prevent the action of bile acid salts as a solubilizers of specific pharmaceutically active substances. The PhD thesis examined the the critical micelle concentration of the mixed micelles of sodium salt of 3 bile acid (cholic, deoxycholic, and 7-oksodeoksiholne acid) and sodium dodecyl sulphate at various temperatures, the mole fractions ranging from 0 to 50 °C using the method of spectrofluoriphotometry by pirene as a probe molecule.</p>
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LA NUOVA DISCIPLINA DEI CONTRATTI DERIVATI OVER THE COUNTERGROSSULE, EDOARDO 13 March 2015 (has links)
Il presente lavoro si propone di analizzare in una prospettiva funzionale la nuova disciplina dei contratti derivati over the counter introdotta in Europa con il Regolamento 648/2012 (EMIR) e in USA con il Dodd-Frank Act, con l’obbiettivo di metterne in luce punti di forza e di debolezza.
Per perseguire compiutamente detto obiettivo, la tesi propone un percorso logico che parte dall’approfondimento delle cause economico-giuridiche che hanno favorito il propagarsi degli effetti negativi della crisi, che successivamente si sofferma sulle possibili risposte normative ai problemi posti dagli strumenti derivati. Infine, l’analisi si termina sottolineando gli aspetti problematici legati all’effettività della nuova disciplina, soprattutto alla luce delle policy dynamic che si sviluppano intorno al lungo procedimento di approvazione di norme complesse. / This dissertation aims at analyzing, with a functional approach, the new regulations of over the counter derivatives introduced in Europe with the 648/2012 Regulation (EMIR) and in the US under the Dodd-Frank Act, with the goal to underlying the strengths and weaknesses.
To fully achieve this objective, the thesis proposes a logical path that starts from the deepening of economic and legal causes that have favored the spread of the negative effects of the crisis, then focuses on possible regulatory responses to the problems posed by derivatives. Finally, the analysis ends pointing out the problematic aspects related to the effectiveness of the new rules, especially in light of the policy dynamic developed during the long process of approval of these complex rules.
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Biološka aktivnost novosintetisanih D-seko i D-homo-estratrienskih derivata u in vivo i in vitro uslovima / Biological activity of the newly synthesized D-secoand D-homoestratriene derivatives in in vivo and in vitro experimentsJovanović-Šanta Suzana 08 October 2010 (has links)
<p>Sintetisana su nova jedinjenja, 16- i 17-supstituisani 16,17-sekoestratrienski derivati i D-homoestranski derivati, polazeći od 3-benziloksi-17-hidroksi-16,17-sekoestra-1,3,5(10)-trien-16-nitrila. Ispitana je estrogena i antiestrogena aktivnost u eksperimentima <em>in vivo</em>, antiaromatazna aktivnost <em>in vitro</em>, antioksidantna aktivnost DPPH i TBA testom, kao i antiproliferativna aktivnost prema ćelijskim linijama MCF-7 ATCC, MDA-MB-231, HT-29 i MRC-5 novosintetisanih jedinjenja.</p> / <p>Some new compounds, 16- and 17-substituted 16,17-secoestratriene derivatives, as well as D-homoestratriene derivatives, were synthesized, starting from 3-benzyloxy-17-hydroxy-16,17-secoestra-1,3,5 (10)-triene-16-nitrile. The newly synthesized compounds were tested for their <em>in vivo </em>estrogenic and antiestrogenic activity, <em>in vitro </em>antiaromatase activity, antioxidative activity by DPPH and TBA tests, as well as antiproliferative activity against MCF-7 ATCC, MDA-MB-231, HT-29 i MRC-5 cell lines.</p>
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Sinteza i biološka aktivnost novih steroidnih heterocikličnih jedinjenja / Synthesis and biological activity of new steroidal heterocyclic compoundsOklješa Aleksandar 24 July 2015 (has links)
<p>U ovoj doktorskoj disertaciji ispitane su 1,3-dipolarne<br />cikloadicione reakcije steroidnih azido-nitrila, nitrona i<br />nitril-oksida, pri čemu su sintetizovana različita<br />heterociklična steroidna jedinjenja androstanske i estranske<br />serije. Utvrdjene su strukture novosintetizovanih<br />jedinjenja. Ispitana je biološka aktivnost odabranih<br />jedinjenja.</p> / <p>In this PhD thesis 1,3-dipolar cycloadditions of<br />steroidal azido-nitriles, nitrones and nitrile-oxide were<br />examined. Various steroidal heterocyclic compounds in<br />the androstane and estrane series were synthesised. The<br />structural characterisation of newly synthesised<br />compounds was done. Biological activity of selected<br />compounds was examined.</p>
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Izolovanje, strukturna karakterizacija i biološka aktivnost naftnih kiselina iz Vojvođanske nafte / Isolatin, structural characterization and biological activity of naphthenic acids from Vojvodina oilGrbović Ljubica 04 December 2009 (has links)
<p>Grupno-strukturna analiza naftnih kiselina izolovanih iz srednjih uljnih komercijalnih frakcija vojvođanske nafte „Velebit” rađena je analizom IR-, <sup>1</sup>H- i <sup>13</sup>C NMR- i ESI-MS spektara niske rezolucije. Određeno je šest klasa karboksilnih kiselina opšte molekulske formule C<sub>n</sub>H<sub>2n-Z</sub>O<sub>2</sub>. To su karboksilne kiseline u opsegu masa 240-466 sa 15-31 C atoma u molekulu koje su grupisane u pet cikloalkil Z-serija: monociklična- (C<sub>n</sub>H<sub>2n-2</sub>O<sub>2</sub>, 14.72%), biciklična- (C<sub>n</sub>H<sub>2n-4</sub>O<sub>2</sub>, 34.63%), triciklična- (C<sub>n</sub>H<sub>2n-6</sub>O<sub>2</sub>, 25.03%), tetraciklična- (C<sub>n</sub>H<sub>2n-8</sub>O<sub>2</sub>, 10.04%), pentaciklična klasa karboksilnih kiselina (C<sub>n</sub>H<sub>2n-10</sub>O<sub>2</sub>, 4.99%) i jedna alkanska klasa kiselina sa alkil grupama otvorenog niza (C<sub>n</sub>H<sub>2n</sub>O<sub>2</sub>, 10.57%).</p><p>Razdvajanjem na bazi različite kiselosti i njihove rastvorljivosti u vodi na određenim pH vrednostima u rasponu od pH 2-10 dobijeno je devet užih frakcija kiselina. Ekstrakcijom sa etrom u vodi nerastvornih kiselina u rasponu od po jedne pH jedinice dobijena je sledeća distribucija masa: 9.57% (pH 10), 12.69% (pH 9), 5.91% (pH 8), 4.85% (pH 7), 2.44% (pH 6), 11.71% (pH 5), 23.94% (pH 4), 16.76% (pH 3) i 10.12% (pH 2). Razdvajanjem kiselina na bazi njihove kiselosti oko 50% mase kiselina ekstrahovano je od pH 2-4, znači u grupi jačih kiselina. Masenom spektrometrijom niske rezolucije ESI-MS na pH 4 vidi se da su u smeši kiselina skoncentrisane kiseline sa više prstenova u alkilnom delu sa maksimumom na tricikličnim kiselinama (36.50%), dok su pojedinačno najzastupljenije tetraciklične strukture kiselina C<sub>20</sub>H<sub>32</sub>O<sub>2</sub>(4.43%) i C<sub>21</sub>H<sub>34</sub>O<sub>2</sub>(4.56%). Na pH 8 biciklične- i triciklične strukture su zastupljene ukupno sa 65.02% sa maksimalno zastupljenim kiselinama sa 20-26 C atoma u molekulu, a izdvajaju se C<sub>22</sub>H<sub>38</sub>O<sub>2</sub> (5.26%) biciklične- i C<sub>24</sub>H<sub>42</sub>O<sub>2</sub>(7.01%) triciklične strukure, a od tetracikličnih struktura kiselina izdvaja se C<sub>24</sub>H<sub>40</sub>O<sub>2 </sub>(4.77%). Na pH 10 najzastupljenije izolovane kiseline su aciklične, odnosno masne kiseline zastupljene sa 25.28%, a najdominantnije su strukture C<sub>21</sub>H<sub>42</sub>O<sub>2</sub> (4.83%), dok su ostale klase kiselina ujednačene po svom masenom udelu u odnosu na sastav u ukupnoj polaznoj smeši kiselina. Drugi deo rada obuvata derivatizaciju izolovanih prirodnih naftnih kiselina. Sintetizovani su funkcionalni kiseonični metil-, etil-, n-butil-, terc-butil- i benzil-derivati naftnih kiselina kao i funkcionalni azotni derivati: amidi i anilidi naftnih kiselina. Sinteze navedenih estara rađene su klasičnim postupcima i modifikovanom metodom esterifikacije u kiselo-katalizovanim uslovima upotrebom mikrotalasa kao ko-katalizatora, što je imalo za cilj skraćenje reakciong vremena i poboljšanje ekoloških sintetskih uslova.<br />Modifikacijom sinteze metilnaftenata MT-zagrevanjem 48 puta je skraćeno vreme trajanja sinteze, prinosi ni promenom reakcionih parametara (vreme, snaga MT) nisu bitno promenjeni. Strukturnom analizom ESI-MS spektra polaznih kiselina i metilnaftenata dobijenih metilovanjem naftnih kiselina utvrđeno je da je odnos klasa u dobroj podudarnosti. Prinos estara u ovoj sintezi je 95.47%. Esterifikacija naftnih kiselina etil alkoholom rađena je u uslovima kisele katalize uz konvencionalno zagrevanje (91.76%), a modifikacijom metode MT-zagrevanjem (150 W) reakciono vreme je skaćeno 96 puta (92.19%). Esterifikacija naftnih kiselina n-butil alkoholom rađena je uz sumpornu kiselinu kao katalizator i uz konvencionalno zagrevanje (94.24%), a u uslovima MT-zagrevanja (150 W) 72 puta je skraćeno reakciono vreme (61.15%). Sinteza terc-butilnaftenata rađena je prevođenjem naftnih kiselina u hloride a zatim reakcijom sa terc-butil alkoholom nastaju terc-butilnaftenati (80.17%). Modifikovanom metodom klasične reakcije esterifikacije naftnih kiselina terc-butil alkoholom katalizovanom sumpornom kiselinom u uslovima MT-zagrevanja (150 W) ostvaren je prinos od 85.49% a vreme trajanja reakcije je 5 minuta. Sinteza benzilnaftenata rađena je prevođenjem naftnih kiselina u hloride a zatim reakcijom sa benzil alkoholom nastaju benzilnaftenati (84.43%), a modifikovanom metodom klasične kiselo-katalizovane esterifikacije naftnih kiselina benzil alkoholom u uslovima MT-zagrevanja (150 W) ostvaren je prinos od 85.49% uz reakciono vreme od 5 minuta. Sinteza amida naftnih kiselina rađena je iz hlorida reakcijom sa amonijakom. Prinos čistih amida je 65.74%, a reakcija amidacije sa amonijakom trajala je 15 minuta. Strukturnom analizom ESI-MS spektra amida naftnih kiselina utvrđen je grupno-strukturni sastav amida. Među strukturama amida naftenskih kiselina takođe su dominantne biciklične- i triciklične strukture, kao i u smeši slobodnih kiselina. Sinteza anilida naftnih kiselina rađena je iz hlorida reakcijom sa anilinom. Prinos čistih anilida je 96.48%, a reakcija amidacije anilinom trajala je 30 minuta. Strukturnom analizom ESI-MS spektra anilida naftnih kiselina utvrđen je grupno-strukturni sastav proizvoda, anilida. Među strukturama anilida naftenskih kiselina takođe su dominantne biciklične- i triciklične strukture kao i u smeši slobodnih kiselina.</p><p>U trećem delu ovog rada ispitivana je biološka aktivnost naftnih kiselina auksinskog i giberelinskog tipa, njihov uticaj na ožiljavanje reznica, ukorenjivanje bočnih grana i mikroizdanaka biljaka, na aktivnost biljnih hormona, kao i na usvajanje metalnih jona kod biljaka. </p><p>Aktivnost naftenskih kiselina utvrđena je pomoću tri in vitro biološka testa. „Koleoptil test”, rađen je na dva supstrata, odnosno na semenu ozime pšenice novosadske sorte Partizankai jare pšenice takođe novosadske sorte Venera. Referentna aktivnost u testu rađena je sa -naftilsirćetnom 3-indolsirćetnom kiselinom. U oba testa ustanovljen je približno isti odnos aktivnosti rastvora naftenskih kiselina i aktivnosti standardnih biljnih hormona. „Test inhibicije klijanja” semena rađen je sa semenom crne slačice, Brasscia nigra. Najveći uticaj naftenskih kiselina na inhibiciju klijanja postignut je u rasponu koncentracija kiselina od 10<sup>-7</sup> -10<sup>-8 </sup>mol/L (0.05-0.01 mg/L). Testovi za šest užih frakcija dobijenih iz smeše ukupnih kiselina razdvajanjem na bazi različite rastvorljivosti pri različitim pH vrednostima pokazuju istu aktivnost kao 3-indolsirćetna kiselina (0.5 mg/L), a da je frakcija izdvojena iz vodenog rastvora na pH 7 takođe aktivna ali u poređenju sa 3-indolsirćetnom kiselinom to je 10 puta niža aktivnost. Hormonska aktivnost giberelenskog tipa ispitivanih kalijumovih soli naftenskih kiselina utvrđena je „Endosperm testom”, u kojem je određivana aktivnost amilaze spektrofotometrijskim praćenjem povećanja koncentracije redukujućih šećera u endospermu semena tretiranog ječma i poređena sa aktivnošću rastvora giberelinske kiseline (GA3). Rezultati ovih testova pokazuju da delovanjem vodenih rastvora užih frakcija naftenskih kiselina u koncentraciji 1.0 mg/L (3.5 x 10<sup>-6 </sup>mol/L)frakcija izolovana pri pH 8 ima aktivnost koja je približno u opsegu aktivnosti giberelina koncentracije 10<sup>-2</sup>-10<sup>-3 </sup>mg/L. </p><p>Natrijum-naftenati u koncentraciji od 10<sup>-6 </sup><br />do 10<sup>-8 </sup>mol/L stimulišu formiranje adventivnih korenova kod reznica suncokreta pa je broj korenova po biljci 40 puta veći kod biljaka koje su bile potopljene u rastvor natrijum-naftenata u odnosu na one koje su bile potopljene u vodu, a sličan efekat utvrđen je i pri tretiranju bočnih grana suncokreta. </p><p>Ožiljavanje drvenastih biljaka rađeno je na reznicama bele topole (Populus alba) i reznicama američke crne topole (Populus deltoides). Uočen je jasan inhibitomi efekat na rast korenčića i izbojka u vodenom medijumu sa 10<sup>-4 </sup>mol/L naftenskih kiselina, dok je tretman od 24 časa doprineo većem broju korenčića na donjih 5 cm reznice, kao i ukupnog broja korenčića nego kod kontrole. </p><p>U testu ukorenjivanja mikroizdanaka kod hrizantema najveći broj korenova dobijen je nakon tretmana sa rastvorom koji sadrži 10 µmol/L ukupnih naftenata i tretmanom sa 50 µmol/Lfrakcijom kiselina izolovanom pri pH 7. Oba rezultata su na nivou aktivnosti 3-indolbuterne kiseline koncentracije 10 µmol/Lšto znači da u ovom slučaju frakcionacija nije neophodna. </p><p>Efekti natrijum-naftenata na ukorenjivanje praćeni su merenjem nivoa totalnih peroksidaza i amilaze, kao i sadržaja redukujućih šećera i ukupnih proteina u bazalnim delovima reznica bagrema(Rozaszin-AC). Nakon 1; 3 i 6 dana reznice su uzete za biohemijske analize. U svakom slučaju, aktivnosti IAA-oksidaze i amilaze su se povećavale do trećeg dana, a zatim smanjuje. Efekat je bio jače izražen posle tročasovnog tretmana sa natrijum-naftenatima u poređenju sa šestočasovnim tretmanom i kontrolom. Sadržaj rastvornih proteina je bio povećan jedan dan posle tretmana, smanjen trećeg i ponovo povećan šestog dana, osim za šestočasovni tretman natrijum-naftenatima, kada je efekat bio sasvim suprotan.</p><p>Test uticaja naftnih kiselina na nivo kadmijuma u biljkama pokazuje fiziološko delovanje naftnih kiselina na snižavanje nivoa teških metala u biljci, u ovom slučaju kadmijuma. Ispitivan je efekat niske koncentracije natrijum-naftenata (10<sup>-7 </sup>mol/L) na ukupan sadržaj Cd u pojedinim frakcijama interćelijskog prostora kao i unutar ćelija, kao i na neke fiziološke i biohemijske parametre kod mladih biljaka soje koje su uzgajane u prisustvu kadmijum-hlorida koncentracije 1 mmol/L. Prisustvo naftenata smanjuje sadržaj ukupnog kadmijuma kako u korenu tako i u stablu i listovima u proseku za oko 40% i ublažava štetne efekte kadmijuma na aktivnost nitrat-reduktaze kao i na sadržaje fotosintetskih pigmenata.</p><p>Tretman biljaka niskim koncentracijama natrijum-naftenata utiče na akumulaciju nekih esencijalnih elemenata kod mladih biljaka soje. Prisustvo naftenata (10<sup>-7 </sup>mol/L) značajno povećava sadržaj Mn, Fe, Zn i Ni u korenu, ali u stabljici i listovima samo sadržaj Fe i Mn. U korenu, sadržaj Mn je četiri puta veći a sadržaji Fe, Zn i Ni su povećani 17%, 60% i 68%, respektivno. </p><p>Ispitivanja na celeru i mrkvi su potvrdila da uticaj naftenata na mineralnu ishranu zavisi od primenjenog elementa i da je način preuzimanja određenih jona različit, što ima za posledicu ili povećanje ili smanjenje sadržaja pojedinih jona u nekim delovima biljaka. Mlade biljke celera i mrkve, gajene u hranljivom medijumu, tretirane su natrijumovim solima naftenskih kiselina (10<sup>-7 </sup>mol/L) folijarno ili prisustvom u hranljivom medijumu. Jedino je tretman putem prisustva naftenata u hranljivom medijumu smanjio svežu masu korena i nadzemnog dela oko 20% kod obe biljke.Oba tretmana uticala su na sadržaj Fe, Cu, Mn, Mg i Ca kod biljaka celera i Fe, Mn, Zn i Na kod biljaka mrkve. Kod biljaka celera došlo je do smanjenja sadržaja navedenih nutrienata dok je u korenu biljaka mrkve došlo do povećanja sadržaja Fe za 45%, Mn za 70% i Zn za 37%. Kod ovih biljaka prisustvo naftenata u hranljivom medijumu dovelo do smanjenja mase korenova i nadzemnih delova, što je potpuno suprotno od rezultata dobijenih kod biljaka soje. Folijarnim tretmanom je značajno<br />povećana masa nadzemnog samo kod celera.</p> / <p>Group-structural analysis of naphthenic acids isolated from middle commercial fractions of Vojvodina oil „Velebit” was performed with the analysis of IR-,<br /><sup>1</sup>H- and <sup>13</sup>C NMR- and ESI-MS low resolution spectrums. Six classes of carboxylic acids of the general molecular formula C<sub>n</sub>H<sub>2n-Z</sub>O<sub>2 </sub>were determined. These are carboxylic acids with mass range of 240-466 with 15-31 C atoms in molecule which are grouped in five cycloalkyl <span style="font-size: 12px;">Z-series: monocyclic- (C<sub>n</sub>H<sub>2n-2</sub>O<sub>2</sub>, 14.72%), bicyclic- (C<sub>n</sub>H<sub>2n-4</sub>O<sub>2</sub>, 34.63%), </span><span style="font-size: 12px;">tricyclic- (C<sub>n</sub>H<sub>2n-6</sub>O<sub>2</sub>, 25.03%), tetracyclic- (C<sub>n</sub>H<sub>2n-8</sub>O<sub>2</sub>, 10.04%), pentacyclic </span><span style="font-size: 12px;">class of carboxylic acids (C<sub>n</sub>H<sub>2n-10</sub>O<sub>2</sub>, 4.99%) and one alyphatic class of </span><span style="font-size: 12px;">acids with open chain alkyl groups (C<sub>n</sub>H<sub>2n</sub>O<sub>2</sub>, 10.57%).</span></p><p>By fractioning on the basis of different levels of acidity and their solubility in water with pH values ranging from pH 2-10 nine subfractions of acids were obtained. By extraction with ether in water undissolved acids in the range of one pH unit the following distribution of mass was performed: 9.57% (pH 10), 12.69% (pH 9), 5.91% (pH 8), 4.85% (pH 7), 2.44% (pH 6), 11.71% (pH 5), 23.94% (pH 4), 16.76% (pH 3) and 10.12% (pH 2). By fractioning acids on the basis of their acidity about 50% of acid mass was extracted at pH 2-4, i.e., in the group of stronger acids. Low resolution mass spectrometry ESI-MS shows that at pH 4 acids with more rings in the alkyl <br />section were concentrated in the mixture with maximum at tricyclic acids (36.50%), while individually tetracyclic acid structures C<sub>20</sub>H<sub>32</sub>O<sub>2</sub> (4.43%) and C<sub>21</sub>H<sub>34</sub>O<sub>2 </sub>(4.56%) were most prominent. At pH 8 bicyclic- and tricyclic structures are represented together by 65.02% with acids with 20-26 C atoms in molecule being represented the most, and C<sub>22</sub>H<sub>38</sub>O<sub>2</sub> (5.26%) bicyclic- and C<sub>24</sub>H<sub>42</sub>O<sub>2</sub>(7.01%) tricyclic structures stand out, while with tertacyclic acid structures C<sub>24</sub>H<sub>40</sub>O<sub>2</sub> (4.77%) stands out. At pH 10 most represented isolated acids are acyclic, i.e., fatty acids which are represented by 25.28%, with the most dominant C<sub>21</sub>H<sub>42</sub>O<sub>2 </sub>structures (4.83%), while the other classes of acids are well balanced in their mass share in relation to the composition of the overall initial acid mixture.</p><p>The second part of this work deals with derivatization of the isolated natural naphthenic acids. Functional oxygen methyl-, ethyl-, n-butyl-, tert-butyl and benzyl-derivatives of naphthenic acids as well as functional nitrogen derivatives: amides and anilides of naphthenic acids were synthesized. The syntheses of the above mentioned esters were performed by conventional methods and by a modified method of esterification in acid-catalyzed conditions using microwaves as a co-catalyst with the aim of shortening the reaction time and improving the ecological synthetic conditions. </p><p>By modification of methyl naphthenates synthesis using MT-heating the time period for synthesis is reduced 48 times and the yield does not significantly change even after the reaction parameters (time, MT power) have been altered. Using structural analysis of ESI-MS spectrum of initial carboxylic acids and the methyl naphthenates obtained through methylation of naphthenic acids it was establishedthat the class ratio shows great compatibility. The esters yield in this synthesis is 95.47%. The esterification of naphthenic acids with ethyl alcohol done under the conditions of acid catalysis with conventional heating (91.76%), and with the modified method MT-heating (150 W) the reaction time is reduced 96 times (92.19%). The esterification of naphthenic acids with n-butyl alcohol was performed using sulphuric acid as a catalyst with conventional heating (94.24%), and under MT-heating conditions (150 W) reaction time was 72 times shorter (61.15%). The synthesis of tert-butyl naphthenates was performed by conversion of naphthenic acids into chlorides, followed by the reaction with tert-butyl alcohol which resulted in tert-butyl naphthenates (80.17%). By the modified method of conventional reaction of esterification of naphthenic acids using tert-butyl alcohol catalysed with sulphuric acid in MT-heating conditions (150 W) the yield was 85.49% and reaction time was 5 minutes. The synthesis of benzyl naphthenates was performed by conversion of naphthenic acids into chlorides, followed by a reaction with benzyl alcohol which produces benzyl naphthenates (84.43%), whereas the modified method of conventional acid-catalysed esterification of naphthenic acids using benzyl alcohol under MT-heating (150 W) conditions the yield was 85.49% with the reaction time of 5 minutes. </p><p>The synthesis of naphthenic acid amides was done from chlorides by reaction with ammonia. The yield of pure amides was 65.74%, and the reaction of amidation with ammonia lasted for 15 minutes. The structural analysis of ESI-MS spectrum of naphthenic acid amides determined the group-structural composition of amides. With the structures of amides of naphthenic acids bicyclic- and tricyclic structures are also dominant, as in the mixture of free acids. The synthesis of naphthenic acid anilides were performed from chloride by reacting with aniline. The yield of pure anilides <br />was 96.48%, and the reaction of amidatation lasted for 30 minutes. The structural analysis of ESI-MS spectrum of naphthenic acid anilides determined the group-structural composition of anilide products. With the structures of anilides of naphthenic acids bicyclic- and tricyclic structures are also dominant, as in the mixture of free acids.</p><p>The third part of this work tests the biological activity of naphthenic acids of auxine and gibberellinic type, their influence on the rooting of cuttings, lateral branches and microshoots of plants, on the activity of plant hormones as well as on the metal ions uptake by plants. </p><p>The activity of naphthenic acids was determined using three in vitro biological tests. „Koleoptil test”, was done on two substrates, namely the seed of winter wheat of the Partizankasort and the spring wheat of the Venerasort. The referential activity in the test was performed with α-naphthylacetic- and 3-indolacetic acid. Both tests showed approximately the same ratio of activity of naphthenic acid solutions and standard plant hormones. „Germination Inhibition Test” of the seed was performed using <br />Brasscia nigraseed. The greatest influence of naphthenic acids to germination inhibition was achieved in the acid concentration ranging from 10<sup>-7</sup>-10<sup>-8 </sup>mol/L (0.05-0.01 mg/L). The tests for six narrow fractions obtained from the overall mixture of acids through fractioning on the basis of different solubility at different pH values show the same activity as 3-indolacetic acid (0.5 mg/L), with the fraction isolated from the aqueous solution at pH 7 also active but in comparison to 3-indolacetic acid this activity was 10 times lower. Hormone activity of gibberellinic type of the potassium salts of naphthenic acids was determined using “Endosperm Test” where amylase <br />activity was determined by spectrophotometric measuring of the increase of the concentration of reducing sugars in endosperm in the treated barley seed which was then compared to the activity of the gibberellic acid solution (GA3). The results of these tests indicate that the activity of aqueous solutions of narrow fractions of naphthenic acids in the concentration of 1.0 mg/L (3.5 x 10<sup>-6 </sup>mol/L)the fraction isolated at pH 8 has the activity which is approximately within the range of activities of gibberellin of the concentration of 10<sup>-2</sup>-10<sup>-3 </sup>mg/L. </p><p>Sodium salts of naphthenic acids in concentrations of 10<sup>-6 </sup>do 10<sup>-8 </sup>mol/L stimulated formation of adventitious roots in <span style="font-size: 12px;">sunflower cuttings even by a </span><span style="font-size: 12px;">factor of 40 compared with control, the effect being also observed lateral </span><span style="font-size: 12px;">branches of interspecies sunflower hybrids. The obtained results suggest </span><span style="font-size: 12px;">the possibility of using naphthenic acids as a means for rooting of plant </span><span style="font-size: 12px;">cuttings.</span></p><p>Rooting of hardwood plants was investigated on the cuttings of white poplar (Populus alba) and black poplar (Populus deltoides). The distinct inhibitory effect on the root and shoot growth in water culture was detected in the concentration of naphtenic acids 10<sup>-4 </sup>mol/L, but 24-hour treatment raised the number roots on undermost 5 cm of the cutting, as well as the total number of roots, comparing to the control.</p><p>In the test of rooting microshoots ofchrysanthemum the highest number of <span style="font-size: 12px;">roots was achieved after the treatment with solution containing 10 µmol/L of </span><span style="font-size: 12px;">total napthenates, as well as after the treatment with fraction of naphthenic </span><span style="font-size: 12px;">acids which was isolated at pH 7 in concentration of 50 µmol/L. Both results </span><span style="font-size: 12px;">are on the level of activity of 3-ndolbutyric acid in concentration of 10 µmol/L </span><span style="font-size: 12px;">which suggests that in this case ractionation is not necessary.</span></p><p>The effects of sodium naphthenates on rooting were investigated by measuring the level of total peroxidases and amylase, along with the contents of reducing sugars and total proteins in basal parts of cuttings of black locust (Rozaszin-AC). After 1; 3 and 6 days cuttings were taken for biochemical analysis. In all cases, the activities of IAA-oxidase and amylase increased to the third day and showed a decrease afterwards. The effect was more pronounced after the three-hour treatment with sodium naphthenates, compared to the six-hour treatment and control. The content of soluble proteins increased one dayafter the treatment and decreased to the third and again increased to the sixth day, an exception being the six-hour treatment with sodium naphthenate, when the effect was completely opposite.</p><p>The test of naphthenic acids influence on the level of cadmium in plants showed physiological activity of naphthenic acids on the decrease of the level of heavy metals, in this case cadmium, in the plant. The effect of low concentrations (10<sup>-7 </sup>mol/L) of sodium naphthenate on total content of Cd in the intercellular space and inside cells, as well as on some physiological and biochemical parameters of young soybean plants grown in the presence of 1 mmol/L solution of cadmium chloride was investigated. Presence of naphthenate reduced in average by 40 % content of total and intracellular Cd in root, stem and leaves and alleviated the harmful effect of <br />Cd on activity of nitrate reductase and content of photosynthetic pigments.</p><p>Treatment of soybean plants with low concentrations of sodium naphthenate influenced the accumulation ofsome essential elements by the young plants. The presence of naphthenates (10<sup>-7 </sup>mol/L) significantly increased content of Mn, Fe, Zn and Ni in root, but in stem and leaves increased only contents of Fe and Mn. Inroot, the content of Mn increased four times while contents of Fe, Zn and Ni increased by 17%, 60% and 68% respectively compared to the control.</p><p>Investigations on celery and carrot confirmed that the influence of naphthenates on mineral nutrition depends on the applied element and that the way of uptake of certain ions is different, which results in either increase or decrease of the contents of some ions in certain parts of plants. Young plants of celery and carrot, were grown in the nutrient medium and treated with sodium salts of naphthenic acids (10<sup>-7 </sup>mol/L) over the leaves or with its presence in the nutrient medium. Only the treatment based on the presence of naphthenates in the nutrient medium resulted in the decrease of the fresh mass of root and aboveground part by about 20% for both plants. Both treatments had influence on the content of Fe, Cu, Mn, Mg and Ca in the plants of celery and Fe, Mn, Zn and Na in the plants of carrots. In the plants of celery the content of the mentioned nutrients was decreased, while in the root of plants of carrot the content was increased, Fe by 45%, Mn by 70% and Zn by 37%. With these plants the presence of naphthenates in the nutrient medium caused the reducing roots and aboveground parts, which is completely opposite from the results obtained with soybean plants. The treatment by leaves significantly increased the mass of aboveground part only with celery.</p>
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Sinteza i biološka ispitivanja novih derivata žučnih kiselina / Synthesis and biological evaluation of new bile acid derivativesBjedov Srđan 07 April 2017 (has links)
<p>U disertaciji je ostvarena sineza amida i oksazolina žučnih kiselina, kao i njihovih alkil i alkilidenskih derivata polazeći od holne kiseline. Ipitano je ponašanje različitih okso derivata žučnih kiselina u uslovima Grignard-ove i Wittig-ove reakcije. Ispitana je biološka aktivnost odabranih sintetizovanih jedinjenja</p> / <p>Synhesis of bile acid amide and oxazoline derivatives, and their alkyl and alkylidene derivatives was accomplished starting from cholic acid. Also, chemical behavior of different bile acid oxo derivatives in Grignard and Wittig reaction was investigated. Biological activity of selected synthesized compounds was evaluated.</p>
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Uticaj fizičko-hemijskih svojstava mikroplastike i odabranih perzistentnih organskih polutanata na interakcije u vodenom matriksu / Impact of physicochemical properties of microplastics and selected persistent organic pollutants on interactions in the aqueous matrixLončarski Maja 20 October 2020 (has links)
<p>Mikroplastika je sveprisutna u vodenom ekosistemu pri čemu se često<br />ističe značaj ispitivanja njihovog uticaja na ponašanje drugih jedinjenja u vodi.<br />Pod pojmom mikroplastika podrazumevaju se plastične čestice manje od 5 mm.<br />Imajući u vidu potrebu za unapređenjem znanja o štetnom uticaju mikroplastike<br />u životnoj sredini u ovom radu sproveden je set eksperimenata u kom je ispitivan<br />mehanizam interakcija koje se uspostavljaju prilikom adsorpcije hlorovanih<br />fenola, derivata benzena i policikličnih aromatičnih ugljovodonika na mikroplastici u vodenom matriksu. Kako bi se što detaljnije razumeo uticaj mikroplastike i osobina vodenog matriksa na ponašanje organskih polutanata, laboratorijska ispitivanja su sprovedena u sintetičkom i realnom vodenommatriksu. Takođe je sprovedena optimizacija izolovanja i karakterizacije mikroplastike iz kozmetičkih sredstava u cilju procene uticaja osobina primarne mikroplastike na uspostavljanje interakcija sa organskim polutantima. Na osnovu dobijenih rezultata istraživanja može se zaključiti da se optimalna metoda izolovanja mikroplastike iz kozmetičkih sredstava zasniva na dodatnom tretiranju osušenog materijala 30% vodonik-peroksidom, nakon ekstrakcije sredstva u destilovanoj vodi, u cilju dobijanja čistijih uzoraka mikroplastike. Promena brzine mešanja ima znčajan uticaj na promenu stepena adsorpcije ispitivanih grupa organskih jedinjenja. Uticaj se ogleda u povećanju stepena adsorpcije sa porastom brzine mešanja, a maksimalni procenat adsorpcije postignut je pri brzini mešanja od 150 o/min. Dodatno, disperzija praškastih materijala u vodi nema značajan uticaj na promenu stepena adsorpcije hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika na mikroplastici.Ravnotežno stanje između koncentracije hlorovanih fenola, derivata<br />benzena i policikličnih aromatičnih ugljovodonika u vodi i odabranih predstavnika mikroplastike (PEp, PE_PCPs_1, PE_PCPs_2, PEg, PET, PP i PLA) uspostavlja se nakon 24 i 48 h kontakta u zavisnosti od vrste jedinjenja. Na promenu adsorpcionog afiniteta hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika prema mikroplastici utiču kako fizičkohemijske osobine jedinjenja tako i karakteristike mikroplastike. Na osnovu kinetičkih eksperimenata, najveći adsorpcioni afinitet ka mikroplastici ispoljili su derivati benzena (qt=103-350 µg/g), dok je najmanji uočen kod hlorovanih fenola (qt=25-225 µg/g). Dobijeni rezultati adsorpcije derivata benzena na ispitivanim česticama mikroplastike takođe su ukazali na veći afinitet ovih jedinjenja ka mikroplastici, u poređenju sa jedinjenjima iz grupe policikličnih aromatičnih ugljovodonika i hlorovanih fenola sličnih logKow vrednosti. Dodatno, uticaj vodenog matriksa na adsorpciju hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika na mikroplastici zavisi od same grupe jedinjenja kao i od vrste mikroplastike pri čemu je najmanje izražen u slučaju ispitivanih policikličnih aromatičnih ugljovodonika, a najviše kod hlorovanih fenola.Visoke vrednosti koeficijenta determinacije kinetičkog modela pseudodrugog reda za adsorpciju hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika na čestice mikroplastike ukazjuju da je hemisorpcija mogući mehanizam. Pored visokih vrednosti koeficijenata determinacije u slučaju svih odabranih organskih jedninjenja dobijena konstanta brzine drugog reda bila je manja od po četne brzine adsorpcije što ukazuje na znatno brže odvijanje adsorpcije pri kraćim vremenima kontakta (12-24 h) nakon čega je<br />dolazilo do usporavanja procesa adsorpcije.Mehanizam adsorpcije hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika ispitivan je primenom Freundlich-ovog, Langmuirovog, Redlich-Peterson-ovog i Dubinine-Radusckevich-evog adsorpcionog modela. Vrednosti Freundlich-ovog eksponenta za adsorpciju hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika bile su manje od 1,<br />što ukazuje na to da je slobodna energije adsorpcije na mikroplastci opadala sa povećanjem inicijalne koncetracije ispitivanih polutanata. Vrednosti maksimalnog adsorpcionog kapaciteta dobijene za adsorpcione procese PAH na česticama mikroplastike bile su u opsegu od 29,7-2596,5 µg/g. Visoke vrednosti maksimalnih adsorpcionih kapaciteta dobijene su takođe za adsorpciju derivata benzena na ispitivanim vrstama mikroplastike 39,3-2010,1 µg/g. S druge strane, uočeno je različito adsorpciono ponšanje hlorovanih fenola u zavisnosti od vodenog metriksa u kom su eksperimenti sprovedeni pri čemu su qmax vrednosti iznosile 20,00-205,6 µg/g. Značajan uticaj pH vrednosti vodenog matriksa utvrđen je za adsorpciju hlorovanih fenola na mikroplastici, dok u slučaju derivata benzena i PAH promena pH vrednosti vodenog matriksa nije pokazala značajan uticaj. Rezultati dobijeni za adsorpciju hlorovanih fenola na mikroplastici ukazuju na nižu tendenciju ka formiranju interakcija hlorovanih fenola sa česticama mikroplastike pri pH 4 i pH 10, pri čemu se stepen adsorpcije kretao u opsegu od 8-35% i 15-35%, respektivno, u odnosu na pH 7 (55-65%). Najniži adsorpcioni afinitet uočava se pri adsorpciji ispitivanih grupa jedinjenja na PLA. Može se pretpostaviti da će se organski polutanti, ukoliko ova vrsta mikroplastike dospe u vodene sisteme, slabo vezivati na ovaj materijal pri čemu će značajno manje uticati na njihov trasport kroz životnu sredinu, u odnosu<br />na druge ispitivane vrste mikroplastike. Na osnovu dobijenih rezultata istraživanja može se zaključiti da na adsorpciju ispitivanih grupa organskih jedinjenja i mikroplastike značajan uticaj imaju fizičko-hemijske osobine ispitivanih jedinjenja kao što su kiselinska konstanta, veličina molekula, hidrofobnost, stukturni raspored i dr. Pored toga, karakteristike vodenog matriksa, među kojima je najvažnija pH vrednost, imaju značajan uticaj na adsorpcioni afinitet jedinjenja ka mikroplastici. Dodatno,<br />struktura i poreklo polimera ima veliki uticaj na formiranje interakcija sa<br />ispitivanim grupama organskih polutanata. Dobijeni rezultati takođe ukazuju na<br />nemogućnost određivanje unifomnog mehanizma adsorpcije organskih<br />jedinjenja na česticama mikroplastike u vodi.</p> / <p>Microplastics are ubiquitous in aquatic ecosystems, so it is essential to study their impact on the behaviour of other compounds which are commonly present in water. The term microplastics refers to all plastic particles smaller than 5 mm. In order to address knowledge gaps relating to the potential harmful effects of microplastics in the environment, the experiments conducted during this thesis were designed to investigate the adsorption mechanism of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastics in water. To provide a more detailed understanding of the influence of different water matrices on adsorption properties of microplastics, experiments were conducted in both synthetic and real water matrices. In the course of this work, methods were optimised for the isolation and characterization of microplastifrom personal care products, in order to allow investigation of the influence of the properties of primary microplastics on their interactions with organic pollutants.Base on the obtained results, it can be concluded that the optimal method of isolating microplastics from personal care products is based on treating already dried material with 30% hydrogen peroxide, after extraction of the agent in distilled water, in order to obtain cleaner microplastic samples. The mixing rate was found to have a significant effect on the degree of adsorption of the investigated organic compounds. Increasing the mixing speed led to a higher<br />degree of adsorption, with the maximum adsorption percentage reached at a<br />mixing speed of 150 rpm. In addition, the dispersion of powdered materials in the water had no significant effect on the degree of adsorption of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastics.<br />The adsorption equilibrium between the concentration of chlorinated phenols, benzene derivatives and polycyclic aromatic hydrocarbons in water and selected types of microplastics (PEp, PE_PCPs_1, PE_PCPs_2, PEg, PET, PP, and PLA) was established after 24 and 48 h of contact time, depending on the selected group of organic pollutants. The adsorption affinity of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons towards microplastics was influenced by both the physicochemical properties of the compounds and the characteristics of the microplastics. Based on the kinetic experiments, the highest adsorption affinity for microplastics was shown by benzene derivatives (qt=103-350 µg/g), while the lowest was observed during the adsorption of chlorinated phenols (qt=25-225 µg/g). Benzene derivatives showed higher adsorption affinities for the selected microplastic particles than the polycyclic aromatic hydrocarbons and chlorinated phenols which had similar logKow values. The influence of the water matrix on adsorption of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastics depended on the specific functional groups of the investigated compounds as well as on the type of microplastics. Water matrix had little impact on the adsorption of polycyclic aromatic hydrocarbons on microplastics but greatly impacted the adsorption of chlorinated phenols. Fitting the pseudo-second order kinetic model to the adsorption data of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastic particles resulted in high correlation coefficients, indicating that chemisorption is the likely adsorption mechanism. In addition to the high correlation coefficients obtained for all the organic pollutants investigated, the pseudo-second order rate constants obtained were lower than the initiaadsorption rate, indicating significantly faster adsorption at shorter contact times (12-24 h), with adsorption slowing down as equilibrium was reached.The adsorption mechanism of chlorinated phenols, benzene derivatives,<br />and polycyclic aromatic hydrocarbons was investigated using Freundlich,Langmuir, Redlich-Peterson, Dubinine-Radusckevich, and Temkin adsorption models. The Freundlich exponent values for the adsorption of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons were less than 1 which indicates that the free energy of adsorption of these compounds on microplastics decreases as the initial concentration increases. The maximum adsorption capacities of PAHs on microplastic particles were in the range of 29.7-2596.5 µg/g. High maximum adsorption capacities were also obtained for the adsorption of benzene derivatives on the tested types of microplastics: 39.3-2010.1 µg/g. The chlorinated phenols behaved differently, and were more effected by the water matrix, with qmax values in the range 20.00-205.6 µg/g. The pH of the water matrix was found to have a significant effect on the adsorption of chlorinated phenols on microplastics, whereas in the case of benzene derivatives and polycyclic aromatic hydrocarbons, the degree of<br />adsorption was largely independent of the water pH. For the adsorption of chlorinated phenols on microplastics, neutral pH conditions resulted in the greatest degrees of adsorption (55-65% at pH 7), while adsorption was inhibited under acidic (8-35% at pH 4) and basic (15-35% at pH 10) conditions. The microplastic type with the lowest observed adsorption affinities was PLA. It can be thus be assumed that in the event that this type of microplastic enters water systems, organic pollutants will only adsorb weakly to this material, such that it will have significantly less impact on the transport of the se compounds through the environment, than the other tested types of microplastics. The results obtained in this research demonstrate that the adsorption of the selected groups of organic pollutants on the microplastics investigated is significantly controlled by the physicochemical properties of the tested compounds, such as the dissociation constant, molecule size, hydrophobicity,<br />structural properties, etc. In addition, the characteristics of the water matrix play an important role in controlling adsorption of organic pollutants on microplastic, especially the water pH. In addition, the structure and aging of the polymers had a major influence on their interactions with the selected organic pollutants. The obtained results also demonstrate the difficulty in determining a uniform mechanism of adsorption between the various organic compounds and microplastic particles in water.</p>
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