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Karakteristike oleorizina mlevene začinske paprike dobijenog klasičnom i ekstrakcijom superkritičnim ugljen-dioksidom / Characteristics of ground pepper oleoresin, produced byclassic and supercritical fluid extraction with carbon-dioxideTepić Aleksandra 03 September 2009 (has links)
<p>Cilj istraživanja u ovom radu bilo je ispitivanje uticaja<br />različitih vidova ekstrakcije (konvencionalna ekstrakcija<br />organskim rastvaračem i superkritična ekstrakcija ugljendioksidom)<br />na kvalitet oleorizina začinske paprike u pogledu<br />kvalitativnog i kvantitativnog sadržaja bojenih materija,<br />sastava masnih kiselina i antioksidativnih svojstava. Pošto u<br />Vojvodini postoje značajni kapaciteti za proizvodnju i preradu<br />začinske paprike, smatramo da će rezultati ovih ispitivanja<br />dati uvid u kinetiku različitih tipova ekstrakcije i pružiti<br />informacije o uslovima potrebnim za dobijanje proizvoda<br />vrhunskog kvaliteta.</p> / <p>The aim of the work was to investigate the influence of<br />different extraction methods (conventional extraction using<br />organic solvent and supercritical carbon-dioxide extraction)<br />to qualitative and quantitative pigment content, fatty acid<br />content and antioxidant properties of oleoresins. As there<br />have been significant production and processing capacities of<br />spice pepper in Vojvodina, the results of these investigations<br />will give a closer insight into the kinetics of different types of<br />extraction and conditions for obtaining the high quality<br />product.</p>
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Optimizacija metoda ekstrackcije i određivanja neonikotinoida tečnom hromatografijom u odabranim uzorcima / Optimization of extraction and determination of neonicotinoids using liquid chromatography in selected samplesJovanov Pavle 01 July 2014 (has links)
<p>Insekticidi novije generacije, neonikotinoidi, odlikuju se specifičnim načinom delovanja na nervni sistem insekata. Radi dobijanja što brže i kvalitetnije informacije o izloženosti životne sredine ovim insekticidima i količinama njihovih ostataka u hrani potrebno je raspolagati odgovarajućim instrumentalnim metodama za njihovo određivanje. Razvijene su i optimizovane analitičke metode zasnovane na tečnoj hromatografiji za određivanje sedam odabranih neonikotinoida (dinotefurana, nitenpirama, tiametoksama, klotianidina, imidakloprida, acetamiprida i tiakloprida) u medu i likeru od meda. Ispitivana je mogućnost određivanja klotianidina pomoću tečne hromatografije visoke efikasnosti sa detektrorom od niza dioda (HPLC-DAD) primenom kombinacije tečno-tečne i ekstrakcije na čvrstoj fazi iz uzoraka meda. Na osnovu preliminarnih rezultata može se zaključiti da korišćenje faznih-čvrsto kolona u kombinaciji sa tečno-tečnom ekstrakcijom dihlormetanom rezultira prihvatljivim prinosom klotianidina u uzorcima meda pri koncentraciji od oko 0,5 µg g<sup>-1 </sup>klotianidina. Radi dobijanja većih prinosa odabrana je disperzna tečno-tečna mikroekstrakcija (DLLME) kao tehnika pripreme uzoraka meda. Testirana je upotreba acetonitrila kao disperznog sredstva. Pored hloroforma, korišćen je i dihlormetan kao drugo ekstrakciono sredstvo, kako bi se uporedila efikasnost ekstrakcije. Zabeleženi su prinosi klotianidina od 69,7 i 68,3% u zavisnosti da li je korišćen hloroform, odnosno DHM kao rastvor za ekstrakciju. Može se zaključiti da je prinos ekstrakcije bio povoljniji pri odnosu 0,5 mL ACN i 2,0 mL DHM. Prinosi su se kretali od 68,4% do 92,1%, što je ukazalo da su parametri DLLME ekstrakcije optimalni. Kako bi se detaljnije ispitali ključni parametri DLLME tehnike, korišćena je metodologija površine odziva (RSM), kao i detekcija na osetljivijem kuplovanom masenom detektoru (MS/MS). Optimizovani su HPLC-MS/MS parametri kako bi se obezbedilo zadovoljavajuće hromatografsko razdvajanje i niske granice detekcije (GD, 0,5–1,0 μg kg<sup>-1</sup>) i određivanja (GO, 1,0–2,5 μg kg<sup>-1</sup>) ispitivanih neonikotinoida u medu. Upotrebom centralno kompozitnog dizajna konstruisani su kvadratni modeli ispitivanih faktora: zapremine ekstrakcionog (DHM, 1,0–3,0 mL) i disperznog (ACN, 0,0–1,0 mL) sredstva, izračunati statistički parametri i optimizovan proces DLLME upotrebom <em>Derringer</em>-ove funkcije poželjnih odgovora. Upotrebom MMC i SC krivih u opsegu GO–100,0 μg kg<sup>-1 </sup>ispitan je uticaj matriksa pri čemu zaključeno je da je najveći uticaj matriksa bio na odziv analitičkog signala nitenpirama, dinotefurana i klotianidina. Ispitani su prinosi odabranih neonikotinoida (R, 74,3–113,9%), kao i preciznost metode u uslovima ponovljivosti (RSD, 2,74– 11,8%) i intermedijerne reproduktivnosti (RSD, 6,64–16,2%). Brza (retenciona vremena 1,5–9,9 min) i osetljiva metoda, koja troši malu količinu rastvarača, primenjena je za ispitivanje 15 realnih uzoraka meda različitog cvetnog porekla. Rezultati su pokazali da ispitivani med nije sadržao ostatke ispitivanih neonikotinoida u koncentracijama iznad GD. Dalje istraživanje je bilo usmereno ka razvijanju i optimizaciji HPLC-DAD analitičke metode upotrebom DLLME i QuEChERS tehnika za pripremu uzoraka za određivanje 7 neonikotinoida u uzorcima meda. U ovom delu istraživanja optimizovani su i hromatografski parametri, upotrebom RSM sa Box-Behnken-ovim dizajnom i Derringer-ovom funkcijom poželjnih odgovora. Od ispitivanih neonikotinoida dinotefuran i imidakloprid su bili u najvećoj meri izloženi uticaju matriksa, bez obzira na proceduru pripreme uzoraka. Može se istaći da je uticaj matriksa na analitički signal dinotefurana bio izraženiji u slučaju MS/MS, apostrofirajući manju robusnost ove metode određivanja. Prinosi neonikotinoida su bili (R, 73,1–118,3%), preciznost u uslovima ponovljivosti (RSD, 3,28–10,40%) i intermedijerne reproduktivnosti (RSD, 6,45–17,70%), a granice detekcije (GD, 1,5–2,5 µg kg<sup>-1</sup>) i određivanja (GO, 5,0–10,0 µg kg<sup>-1</sup>). Metoda je primenjena za ispitivanje 7 neonikotinoida u 104 uzorkameda različitog cvetnog porekla sa teritorije Autonomne Pokrajine Vojvodine. Detektovano je prisustvo tiakloprida, imidakloprida i tiametoksama u količinama koje su bile ispod MDK RS i EU. Analizirani su uzorci likera od meda - medice. Upoređivane su dve tehnike pripreme uzoraka, DLLME i QuEChERS i primenjeni optimizovani hromatografski uslovi i MS/MS parametri. U slučaju nitenpirama, dinotefurana i tiametoksama uticaj matriksa bio je najizraženiji. Metoda je validovana određivanjem prinosa neonikotinoida (R, 69,2–113,4%), preciznosti u uslovima ponovljivosti (RSD, 3,21–12,81%) i intermedijerne reproduktivnosti (RSD, 9,11–16,63%), kao i granice detekcije (GD, 0,5–2,5 µg kg<sup>-1</sup>) i određivanja (GO, 1,0–10,0 µg kg<sup>-1</sup>). Analizom 10 komercijalno dostupnih likera od meda otkriveno je prisustvo klotianidina i tiakloprida, evčzokinotš z na neophodnost daljeg kontrolisanja ovog proizvoda na prisustvo neonikotinoida. Ispitana je mogućnost uklanjanja odabranih neonikotinoida (dinotefurana, klotianidina i tiakloprida) iz vodene sredine (reke Dunav). Ispitivanje efikasnosti 6 različitih vrsta uklanjanja odabranih neonikotinoida (u prisustvu prirodne insolacije u laboratorijskim uslovima, sa dodatkom H2O2, sa dodatkom MWCNT, sa dodatkom MWCN+H <sub>2</sub>O<sub>2</sub>, sa dodatkom Fe-MWCNT, sa dodatkom Fe-MWCNT+H<sub>2</sub>O<sub>2</sub>) vršeno je upotrebom prethodno razvijene HPLC-MS/MS metode. Krive uklanjanja odabranih neonikotinoida, pokazale su da tokom 60 minuta pri prirodnoj insolaciji u laboratorijskim uslovima koncentracija smanjenje oko 25%. Analitički signal dinotefurana dobijen u prisustvu H<sub>2</sub>O<sub>2 </sub>pod istim uslovima ukazuje na uklanjanje ciljnog analita od oko 40%, tiakloprida od oko 70%, a klotianidina u potpunosti. Testirana je adsorpcija ciljnog analita na višezidnim ugljeničnim nanocevima (MWCNT). Ovim postupkom može da se ukloni oko 30% dinotefurana, oko 50% klotianidina i 60% tiakloprida. U kombinaciji sa H<sub>2</sub>O<sub>2 </sub>, MWCNT pokazuju bolju sposobnost uklanjanja za 15–50% u zavisnosti od ispitivanog neonikotinoida. Upotreba Fe-MWCNT i njihova kombinacija sa H<sub>2</sub>O<sub>2</sub> otvorila je mogućnost za dalja ispitivanja mehanizma uklanjanja. Ustanovljeno je nastajanje intermedijera kojima odgovaraju m/z od 117,5 i 140,6 u slučaju razgradnje dinotefurana u sistemima sa H<sub>2</sub>O<sub>2</sub>, MWCNT+H<sub>2</sub>O<sub>2</sub>, Fe-MWCNT+H<sub>2</sub>O<sub>2 </sub>i klotianidina u sistemu Fe-MWCNT+H<sub>2</sub>O<sub>2</sub>.</p> / <p>Neonicotinoid insecticides, as one of the fastest growing new generation of insecticides, have contributed to a significant reduction of toxicity for the environment; therefore, monitoring and determination of trace levels of the neonicotinoids in honey are necessary and demands highly efficient, selective and sensitive analytical techniques. The objective of the present work was to develop a rapid, sensitive, optimized and accurate analytical method based on liquid chromatography for determining seven neonicotinoid insecticides, dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid in honey and honey liqueur samples. The possibility for determination of clothianidin in honey samples was investigated by HPLC with a diode array detector (HPLC-DAD). Based on preliminary results, it can be concluded that the use of a solid-phase column in combination with a liquid-liquid extraction with dichloromethane results in an acceptable recovery of clothianidin in the samples with a clothianidin concentration of about 0.5 µg g<sup>-1</sup>. After obtaining low recovery of clothianidin, dispersed liquid-liquid microextraction (DLLME) was selected as a technique for the preparation of honey samples.. The adequacy of acetonitrile as a dispersing agent was investigated. Besides the chloroform, a dichloromethane was used as a second extracting agent , in order to compare the relative efficiency of the extraction solvents. It can be concluded that the extraction recovery (68.4–92.1%) was more favorable with the use of 0.5 mL ACN and 2.0 mL DHM. Furthermore, LC-MS/MS parameters were optimized to unequivocally provide good chromatographic separation, low detection (LOD, 0.5–1.0 μg L<sup>−1</sup>) and quantification (LOQ, 1.0–2.5 μg L<sup>−1</sup>) limits for acetamiprid, clothianidin, thiamethoxam, imidacloprid, dinotefuran, thiacloprid and nitenpyram in honey samples. Using different <br />types (chloroform, dichloromethane) and volumes of extraction (1.0–3.0 mL) and dispersive (acetonitrile; 0.0–1.0 mL) solvent and by mathematical modeling it was possible to establish the optimal sample preparation procedure. Matrix-matched calibration and blank honey sample spiked in the <span style="font-size: 12px;">concentration range of LOQ–100.0 μg kg</span><sup><span style="font-size: 12px;">−1 </span></sup><span style="font-size: 12px;">were used to compensate the matrix effect and to fulfill the </span><span style="font-size: 12px;">requirements of SANCO/12495/2011 for the accuracy (R 74.3–113.9%) and precision (expressed in </span><span style="font-size: 12px;">terms of repeatability (RSD 2.74–11.8%) and within-laboratory reproducibility (RSDs 6.64–16.2%)) of </span><span style="font-size: 12px;">the proposed method. The rapid (retention times 1.5–9.9 min), sensitive and low solvent consumption </span><span style="font-size: 12px;">procedure described in this work provides reliable, simultaneous, and quantitative method applicable for </span><span style="font-size: 12px;">the routine laboratory analysis of seven neonicotinoid residues in 15 real honey samples. Neonicotinoid </span><span style="font-size: 12px;">residues were not detected in any of the investigated samples. The objective of next study was to </span><span style="font-size: 12px;">develop and optimize HPLC-DAD analytical method with dispersive liquid-liquid microextraction </span><span style="font-size: 12px;">(DLLME) and QuEChERS sample preparation procedures for the simultaneously analysis of seven </span><span style="font-size: 12px;">neonicotinoids in honey samples. The liquid chromatographic conditions were optimized by response </span><span style="font-size: 12px;">surface methodology with <em>Box-Behnken</em> design and the global <em>Derringer</em>´s desirability. The optimized </span><span style="font-size: 12px;">method was validated to fulfill the requirements of SANCO/12495/2011 standard for both sample </span><span style="font-size: 12px;">pretreatment procedures providing results for accuracy (R, 73.1–118.3%), repeatability (RSD, 3.28–</span><span style="font-size: 12px;">10.40%) and within-laboratory reproducibility (RSD, 6.45–17.70%), limits of detection (LOD, 1.5–2.5 </span><span style="font-size: 12px;">gµ kg</span><sup><span style="font-size: 12px;">-1</span></sup><span style="font-size: 12px;">) and quantification (LOQ, 5.0–10.0 µg kg</span><sup><span style="font-size: 12px;">-1</span></sup><span style="font-size: 12px;">). For the first time, more than 100 honey samples </span><span style="font-size: 12px;">collected from all 7 counties of Autonomous Province of Vojvodina were analyzed. The presence of </span><span style="font-size: 12px;">thiacloprid, imidacloprid and thiametoxam was discovered in a small number of samples. The objective </span><span style="font-size: 12px;">of next study was to develop an optimized LC-MS/MS analytical method with DLLME and QuEChERS </span><span style="font-size: 12px;">procedures for analysis of 7 neonicotinoids in honey liqueur. The method was validated to fulfill the </span><span style="font-size: 12px;">requirements of SANCO/12495/2011 for both sample pretreatment procedures providing results for </span><span style="font-size: 12px;">accuracy (R, 69.2–113.4% for DLLME; 71.8–94.9% for QuEChERS), precision (RSD expressed in </span><span style="font-size: 12px;">terms of repeatability (3.21–10.20% for DLLME; 4.19–12.81% for QuEChERS) and within-laboratory </span><span style="font-size: 12px;">reproducibility (9.11–16.63% for DLLME; 11.32–16.40% for QuEChERS)), limits of detection (LOD, </span><span style="font-size: 12px;">0.5–1.5 gµ L</span><sup><span style="font-size: 12px;">-1 </span></sup><span style="font-size: 12px;">for DLLME; 1.0–2.5 gµ L</span><sup><span style="font-size: 12px;">-1 </span></sup><span style="font-size: 12px;">for QuEChERS) and quantification (LOQ, 1.0–5.0 gµ L</span><sup><span style="font-size: 12px;">-1 </span></sup><span style="font-size: 12px;">for </span><span style="font-size: 12px;">DLLME; 2.5–10.0 µg L</span><sup><span style="font-size: 12px;">-1 </span></sup><span style="font-size: 12px;">for QuEChERS). Analysis of real honey liqueur samples obtained from local </span><span style="font-size: 12px;">markets showed the presence of clothianidin or thiacloprid in four of the analyzed samples, therefore </span><span style="font-size: 12px;">implicating the necessity of ongoing control of this type of traditional product. Removal of selected </span><span style="font-size: 12px;">neonicitinoid insecticides - dinotefuran, clothianidin and thiacloprid using MWCNT and H</span><span style="font-size: 12px;"><sub>2</sub>O<sub>2 </sub></span><span style="font-size: 12px;">from </span><span style="font-size: 12px;">Danube water matrix was investigated. Efficiency of different systems for neonicotinoids removal </span><span style="font-size: 12px;">(under natural insolation in laboratory, with H</span><span style="font-size: 12px;"><sub>2</sub>O<sub>2</sub>, with MWCNT, with MWCNT+ H</span><span style="font-size: 12px;"><sub>2</sub>O<sub>2</sub>, with Fe-MWCNT, with Fe-MWCNT+H<sub>2</sub>O<sub>2</sub>) was evaluated with developed LC-MS/MS method. Analysis of </span><span style="font-size: 12px;">degradation rates revealed loss of 25% of the initial neonicotinoid concentration under natural insolation in </span><span style="font-size: 12px;">the laboratory conditions during 60 min. Addition of chemical agent H<sub>2</sub>O<sub>2 </sub>promoted loss of 40% of the </span><span style="font-size: 12px;">initial dinotefuran, 70% of thiacloprid concentration and total removal of clothianidin under same </span><span style="font-size: 12px;">conditions. With the addition of MWCNT concentration of dinotefuran, clothianidin and thiacloprid </span><span style="font-size: 12px;">decayed for 30, 50 and 60%, respectively. Iron modification of MWCNT in combination with H</span><span style="font-size: 12px;"><sub>2</sub>O<sub>2 </sub></span><span style="font-size: 12px;">increased the removal rate of selected neonicotinoid for 15–50%. Presence of intermediates was </span><span style="font-size: 12px;">discovered in systems of dinotefuran with H<sub>2</sub>O<sub>2</sub>, MWCNT+H</span><span style="font-size: 12px;"><sub>2</sub>O<sub>2</sub>, e-MWCNT+H<sub>2</sub>O<sub>2 </sub></span><span style="font-size: 12px;">and of </span><span style="font-size: 12px;">clothianidin in systems with Fe-MWCNT+H<sub>2</sub>O<sub>2 </sub></span><span style="font-size: 12px;">with m/z of 117,5 and 140,6. </span></p>
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Hemijski sastav, biološke i funkcionalne karakteristike novih proizvoda od zove / Chemical composition, biological and functional characteristics of new elderberry productsVujanović Milena 14 December 2020 (has links)
<p>Glavni cilj ove doktorske disertacije je određivanje hemijskog sastava, bioloških i funkcionalnih karakteristika novih proizvoda od zove. Dobijanje proizvoda na bazi zove zasniva se na primeni tradicionalnih i savremenih tehnoloških procesa proizvodnje. Iskorišćenje prirodnog potencijala zove započeto je primenom tradicionalne i savremene (liofilizacija) tehnike sušenja. U cilju dobijanja visoko-vrednih ekstrakata ploda i cveta zove primenjene su tradicionalna (maceracija) i savremene (ultrazvučna i mikrotalasna) ekstrakcione tehnike sa dva ekstragensa (50% etanol i voda). Dobijanje matičnog soka od plodova zove podrazumevalo je primenu tradicionalnog načina ceđenja, dok je vino od plodova zove dobijeno po standardnom postupku proizvodnje vina. Vino je izloženo različitim temperaturnim tretmanima u različitom vremenskom periodu (60 °C u toku 5 minuta, 60 °C u toku 10 minuta, 70 °C u toku 5 minuta i bez toplotnog tretmana) u cilju evaluacije biološke aktivnosti dobijenog proizvoda. Etarsko ulje ploda i cveta zove je dobijeno hidrodestilacijom. Ispitivanje efikasnosti primenjenih tehnoloških postupaka sušenja i ekstrakcije je zasnovano na određivanju bioloških i funkcionalnih karakteristika dobijenih ekstrakata ploda i cveta zove. U ispitivanim ekstraktima ploda i cveta zove dominantne fenolne kiseline su hlorogenska i protokatehinska kiselina, a rutin i kvercetin-3-O-heksozid su dominantna flavonoidna jedinjenja. Biološke i funkcionalne karakteristike su ispitane primenom različitih in vitro antioksidativnih, neuroprotektivnih, antitirozinaznih i antidijabetogenih testova. Primenom liofilizacije kao savremene tehnike sušenja i mikrotalasne ekstrakcije kao savremene ekstrakcione tehnike povećava se biopotencijal ispitivanih ekstrakata. Matični sok od plodova zove kao potencijalno novi funkcionalni proizvod je analiziran u cilju definisanja hemijskog, fitohemijskog i nutritivnog sastava, biološkog potencijala i senzorskih karakteristika. Ispitivanja dobijenog vina su bila usmerena na utvrđivanje optimalnih uslova za proizvodnju voćnog vina. Definisanjem hemijskog i fitohemijskog sastava i evaluacijom biopotencijala vina određen je optimalan temperaturni profil za dobijanje jednog od novih funkcionalnih proizvoda. Na osnovu utvrđenog hemijskog sastava etarsko ulje ploda i cveta zove se pokazalo kao potencijalno novi prirodni agens za održavanje svežine i produženja roka trajanja prehrambenih proizvoda. Zova je nesumnjivo samonikla biljna vrsta koja u budućnosti osnovano može biti polazna sirovina za kreiranje i dobijanje novih prehrmabenih proizvoda na domaćem i inostranom tržištu.</p> / <p>The main goal of this doctoral dissertation is to determine the chemical composition, biological and functional characteristics of new elderberry products. Elderberry products were obtained via traditional and modern technological processes. The exploitation of the natural potential of the elderberry started with the application of traditional and modern (lyophilization) drying techniques. To obtain high-value extracts of fruits and flowers, traditional (maceration) and modern (ultrasonic and microwave) extraction techniques with two solvents (50% ethanol and water) were applied. Obtaining the juice from the elderberry fruits implied the application of the traditional cold pressing method, whereas wine from the elderberry fruits was obtained in accordance with the standard procedure of wine production. The wine was exposed to different temperature treatments in different periods (60°C for 5 minutes, 60°C for 10 minutes, 70°C for 5 minutes and without heat treatment) to evaluate the biological activity of the product. The essential oil of the fruit and flower was obtained by hydrodistillation. The examination of the efficiency of the applied technological procedures of drying and extraction is based on observing the biological and functional characteristics of the obtained extracts of the said fruits and flowers. In the examined fruit and flower extracts, the dominant phenolic acids are chlorogenic and protocatechuic acid, while rutin and quercetin-3-O-hexoside are the dominant flavonoid compounds. Biological and functional characteristics were examined using various in vitro antioxidant, neuroprotective, antityrosinase, and antidiabetic tests. The application of lyophilization and microwave extraction (as modern drying and extraction techniques) increased the biopotential of the analyzed extracts. Elderberry juice, a potentially new functional product, was analyzed to define the chemical, phytochemical and nutritional composition, biological potential, and sensory characteristics. The wine was tested in order to determine the optimal conditions for the production of fruit wine. By defining the chemical and phytochemical composition and evaluating the biopotential of wine, the optimal temperature profile for obtaining one of the new functional products was determined. Based on the obtained chemical composition, it is determined that the essential oil of fruits and flowers is a potentially new natural agent for maintaining freshness and extending the shelf life of food products. Without a doubt, elderberry is a wild plant species that could be used in the future as the starting material for creating and obtaining new food products on the domestic and foreign markets.</p>
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