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Volatile pollen compounds : bachelor thesis
No full textU ovom radu analiziran je kemijski sastav hlapljivih spojeva peluda sa obiteljskog poljoprivrednog gospodarstava Roguljić koja je ubrana 2020. godine. Hlapljivi spojevi izolirani su metodom mikroekstrakcije vršnih para na krutoj fazi (HS-SPME) sa dva različita vlakna. Dobiveni uzorci analizirani su vezanom tehnikom plinska kromatografija-spektrometrija masa (GC-MS). SPME metodom identificiran je 21 različit spoj. Identificirani spojevi mogu se svrstati u sljedeće kemijske skupine: karboksilne kiseline, alkoholi, esteri, ketoni i aldehidi.In this paper, the chemical composition of volatile pollen compounds from the Roguljić family farm, which was harvested in 2020, was analyzed. Volatile compounds were isolated by headspace solid phase microextraction (HS-SPME) with two different fibers. The obtained data were analyzed by the related technique gas chromatography-mass spectrometry (GC-MS). 21 Different compounds were identified by the SPME method. The identified compounds can be classified into the following groups: carboxylic acids, alcohols, esters, ketones and aldehydes
Preparation of carbon paste sensor with NPOE as binder and NaTPB as sedimentary reagent : master thesis
No full textPripravljena je i opisana ionsko-selektivna elektroda na bazi ugljikove paste za maprotilin hidroklorid (MAP), tetraciklički antidepresiv. Modificirana CPE temelji se na ugljikovoj pasti i maprotilin tetrafenilboratu (MAPTPB) otopljenim u 2-nitrofelinil octileteru (NPOE) kao tekućini za lijepljenje. Ukupan broj pripravljenih i testiranih membrana s različitim udjelima ugljika, NPOE i IAC-a je 18. Najbolje odzivne karakteristike pokazala je membrana 17 koja sadrži 48,87% grafita, 49,00% NPOE, 2,06% IAC-a i 0,07% NaTPB. Tako modificirana elektroda pokazala je Nernstov nagib od -59,14±1,98 mV po koncentracijskog dekadi u području linearnosti od 3,16 x 10 -6 do 3,16 x 10 -3 M . Vrijeme potrebno za uspostavu stabilnog odziva je oko 1 minute. Ovako pripravljeni senzor moguće je primijeniti na određivanje MAP-a u urinu.An ion-selective electrode based on carbon paste for maprotiline hydrochloride (MAP), a tetracyclic antidepressant, was prepared and described. The modified CPE is based on carbon paste and maprotiline tetraphenylborate (MAPTPB) dissolved in 2-nitrophenyl octylether (NPOE) as a bonding fluid. The total number of prepared and tested membranes with different proportions of carbon, NPOE and IAC is 18. The best response characteristics were shown by membrane 17 containing 48.87% graphite, 49.00% NPOE, 2.06% IAC and 0, 07% NaTPB. The electrode thus modified showed a Nernst slope of -59.14 ± 1.98 mV per concentration decade in the linearity range of 3.16 x 10 -6 to 3.16 x 10 -3 M. The time required to establish a stable response is about 1 minute. 2-nitrophenyl octylether. The sensor prepared in this way can be used to determine the MAP in urine
Analysis of different conditions on regenerated cellulose by FTIR : bachelor thesis
No full textUzorci otpadnih celuloznih materijala, vate i staničevine, podvrgnuti su postupku regeneracije celuloze kupramonijevim postupkom pri različitim uvjetima regeneracije. Mijenjala su se vremena i koncentracije sumporne kiseline tijekom regeneracije. Primjenom infracrvene spektroskopije s Fourierovom transformacijom (FTIR) određene su karakteristične apsorpcijske vrpce povezane s fizičkim promjenama uslijed regeneracije celuloze iz vate i staničevine, a sve u svrhu utvrđivanja optimalnih uvjeta regeneracije celuloze iz ovih izvora. Indeks kristalnosti (CI) uz analizu vibracijskih vrpci FTIR spektara uzoraka jasno je ukazao na najbolje regeneriranu celulozu, a time i optimalne uvjete za regeneraciju otpadne vate i staničevine.Samples of the waste cellulosic materials, cotton wool and tissue, were subjected to the cellulose regeneration cuprammonium process under different regeneration conditions. Times and concentrations of sulfuric acid were changed during regeneration. Using Fourier transform infrared spectroscopy (FTIR) characteristic absorption bands associated with the physical changes due to the regeneration of cellulose from cotton wool and cellulose were determined. All of this was to determine the optimal conditions for the regeneration of cellulose from different sources. The crystallinity index (CI) along with the analysis of the vibrational bands of the FTIR spectra of the samples clearly indicated the best regenerated cellulose, and thus the optimal conditions for the regeneration of waste cotton wool and cellulose
Effect of the humic and fulvic acids on mercury and cadmium ions binding onto natural zeolite : diploma thesis
No full textIspitano je vezanje iona žive i kadmija na prirodnom zeolitu u prisustvu otopina Humistar ® i Fertireg ® koji su dodaci tlu u poljoprivredi. Utvrđen je veći stupanj uklanjanja iona žive i kadmija pri nižim početnim koncentracijama kao i niža količina iona vezana po gramu zeolita. Dodatak otopina Humistar ® i Fertireg ® ne utječe na stupanj uklanjanja žive kao i na količinu vezane žive po gramu zeolita. Utvrđeno je povećanje stupnja uklanjanja kadmija uz dodatak otopina Humistar ® i Fertireg ® i to je povećanje više izraženo uz veće koncentracije organske tvari. Također, količina vezanog kadmija po gramu zeolita raste uz dodatak otopina Humistar ® i Fertireg ® te se može zaključiti da organska tvar pozitivno utječe na remedijaciju tla onečišćenog kadmijem, dok na remedijaciju tla onečišćenog živom nema utjecaja pri ispitanim koncentracijama.The binding of mercury and cadmium ions on natural zeolite has been examined in the presence of Humistar ® and Fertireg ® solutions, which are soil additives in agriculture. A higher degree of removal of mercury and cadmium ions at lower initial concentrations was determined, as well as a lower amount of bound ions per gram of zeolite. The addition of Humistar ® and Fertireg ® solutions does not affect the efficiency of mercury removal as well as the amount of bound mercury per gram of zeolite. An increase in removal efficiency of cadmium is observed with the addition of Humistar ® and Fertireg ® solutions, and this increase is more pronounced with higher concentrations of organic matter. Also, the amount of bound cadmium per gram of zeolite increases with the addition of Humistar ® and Fertireg ® solutions, and it can be concluded that organic matter has a positive effect on the remediation of cadmium soil contaminated, while remediation of mercury soil contaminated has no effect at the examined concentrations
Determination of the quality of wheat flour by the Hagberg-Perten falling number method using a lactic acid solution : diploma thesis
No full textZadatak ovog rada bio je ispitati utjecaj otopine mliječne kiseline u određivanju broja padanja po Hagberg-Pertenu u odnosu na standardno određivanje s vodom kao otapalom u uzorcima pšeničnog brašna. Osim toga, ispitan je i utjecaj upotrebe otopine srebrovog nitrata kao sredstva za inaktivaciju amilolitičkih enzima. U radu je korišteno deset uzoraka pšeničnog brašna različite tehnološke kvalitete (četiri jaka, četiri srednje jaka i dva slaba brašna). Provedena je i usporedba dobivenih rezultata određivanja broja padanja s farinografskim i ekstenzografskim pokazateljima kvalitete pšeničnog brašna, kao i s udjelima proteina i glutena te s retencijskom sposobnosti brašna prema vodi i otopini mliječne kiseline i sa sedimentacijskom vrijednosti. Na temelju ispitivanja provedenih u ovom radu može se zaključiti da se upotrebom metode određivanja broja padanja uz korištenje otopina mliječne kiseline i srebrovog nitrata uspješno mogu predvidjeti kvalitativna svojstava brašna ovisna o proteinskoj komponenti. Prilikom korištenja navedenih otopina dolazi do djelomične ili potpune inaktivacije amilolitičkih enzima tako da oni više ne utječu na viskoznost škrobne paste pa se doprinos proteinske komponente brašna viskoznosti suspenzije može bolje uočiti. Iz provedene korelacijske analize može se također zaključiti da se kvalitativna svojstva brašna bolje mogu predvidjeti korištenjem otopine srebrovog nitrata nego li korištenjem otopine mliječne kiseline jer rezultati broja padanja uz upotrebu srebrovog nitrata koreliraju s više pokazatelja kvalitete brašna, a korelaciju su značajnije.The aim of this study was to investigate the influence of the lactic acid solution in the determination of the Hagberg-Perten falling number in comparison with the standard determination using water as solvent in wheat flour samples. In addition, the influence of using silver nitrate solution as an agent to inactivate amylolytic enzymes was also investigated. Ten samples of wheat flour of different technological quality were (four strong, four medium and two weak flours). A comparison of the obtained results for the determination of the falling number with farinographic and extensographic quality indicators of wheat flour, as well as with the protein and gluten content, with the water and lactic acid retention capacity of the flour and sedimentation value was also carried out. Based on the obtained results, it can be concluded that the qualitative properties of flour depending on the protein component can be successfully predicted by the falling number method using lactic acid and silver nitrate solutions. When the above solutions are used, the amylolytic enzymes are partially or completely inactivated so that they no longer affect the viscosity of the starch paste, so that the contribution of the protein component of the flour to the viscosity of the suspension can be better identified. From the correlation analysis performed, it can also be concluded that the qualitative properties of the flour can be better predicted with a silver nitrate solution than with a lactic acid solution, since the falling number results correlate with more flour quality indicators when silver nitrate is used and the correlations are more significant
Phenolic profile and biological potential of red and rose wine vinification by-products : bachelor thesis
No full textProcesom proizvodnje vina nastaju velike količine nusproizvoda poput komine grožđa, pokožica, sjemenki i vinskog taloga. Svi ovi nusproizvodi bogati su bioaktivnim spojevima koji pokazuju brojna biološka svojstva, između ostalog izraženu antioksidacijsku aktivnost. Iako je vinski talog najslabije proučavan nusproizvod vinifikacije, poznato je da je bogat fenolnim spojevima zbog čega sve češće postaje predmetom brojnih studija koje nastoje opravdati njegovu primjenu u prehrambenoj industriji. U ovome radu ispitan je fenolni sastav i biokemijski potencijal vinskog taloga crnog i rosé vina. Ukupni fenoli određeni su metodom po Folin-Ciocalteu, dok je fenolni profil ispitan visokodjelotvornom tekućinskom kromatografijom, HPLC (engl. High performance liquid chromatography) metodom. Antioksidacijska aktivnost ispitana je korištenjem tri različite metode: FRAP (engl. Ferric reducing antioxidant power), DPPH (engl. 2,2-diphenyl-1-picrylhydrazyl free radical scavening) i ORAC (eng. Oxygen radical apsorbance capacity). Rezultati ukazuju na izuzetno bogat fenolni sastav taloga crnog vina u odnosu na talog rosé vina. Najdominantniji fenoli u talogu crnog vina su bili p-hidroksi benzojeva kiselina (89,2 ± 1,1 mg/L) i kvercetin (76,5 ± 0,1 mg/L), dok je u talogu rosé vina udio istih spojeva bio 2,5 do 12 puta niži. Najveću antioksidacijsku aktivnost testiranu FRAP i ORAC metodama pokazao je talog crnog vina, dok je DPPH metodom talog rosé vina pokazao veći antioksidacijski kapacitet.Wine production generates a large amount of by-products such as grape pomace, skins, seeds, and wine lees. All by-products are rich in bioactive compounds that have many beneficial biological properties, including strong antioxidant properties. Although wine lees are among the least studied by- products of winemaking, they are known to be rich in phenolic compounds, and studies on their use in the food industry are increasing. In this work, the total phenols and biochemical potential of red wine and rosé wine lees were investigated. Total phenols were determined by the Folin-Ciocalteu method, while the phenolic profile was studied by high-performance liquid chromatography (HPLC). Antioxidant activity was tested by three different methods: FRAP (Ferric reducing antioxidant power), DPPH (2,2-diphenyl-1- picrylhydrazyl free radical scavenging) and Oxygen radical absorbance capacity (ORAC). The results show that the phenolic composition of red wine lees is very rich compared to rosé wine lees. The most dominant phenols in red wine lees were p-hydroxybenzoic acid (89.2 ± 1.1 mg/L) and quercetin (76.5 ± 0.1 mg/L), while the content of these compounds in rosé wine lees was 2.5 to 12 times lower. Red wine lees showed the highest antioxidant activity by the FRAP and ORAC methods, while the results of the DPPH method were higher in the rosé wine lees
Investigation of the effect of the contact time on sorption of Hg(II) on natural and sulfur-impregnated zeolite : bachelor thesis
No full textU ovom radu je provedena kemijska modifikacija prirodnog zeolita s otopinom Na 2 S pri 150 °C. Ispitano je vremensko zasićivanje prirodnog i sumporom-impregniranog zeolita ionima Hg(II) početne koncentracije ≈ 6 mmol/L tijekom 24 sata. Minimalno vrijeme za postizanje maksimalnog zasićenja oba uzorka iznosilo je 600 minuta. Rezultati su pokazali 2,3 puta veću količinu sorbirane Hg(II) po gramu sumporom-impregniranog zeolita (0,524 mmol/g) u odnosu na prirodni zeolit (0,23 mmol/g), što opravdava modifikaciju.In this paper, the chemical modification of natural zeolite was carried out with Na 2 S solution at 150 °C. The saturation of the natural and the sulphur-impregnated zeolite with Hg(II) ions in time, at an initial concentration of ≈ 6 mmol/L during 24 hours was tested. The minimum time to achieve maximum saturation of both samples was 600 minutes. The results showed a 2.3 times greater amount of sorbed Hg(II) per gram of sulphur-impregnated zeolite (0.524 mmol/g) compared to the natural zeolite (0.23 mmol/g), which justifies the modification
Disubstituted phenanthridine derivative of calix[4]arene for application in theranostic : bachelor thesis
No full textSpektrofotometrijskim titracijama ispitano je kompleksiranje fluorescentnih boja rodamina B, auramina O i fluoresceina, te antitumorskog lijeka timokinona s disupstituiranim fenantridinskim derivatom kaliks[4]arena, 5,11,17,23-tetra-tert-butil-25,27-(bis(6-fenantridinilmetoksi)-26,28- dihidroksikaliks[4]arenom (L), u sustavu otapala acetonitril/diklormetan pri sobnoj temperaturi. Obradom eksperimentalnih podataka određene su konstante stabilnosti kompleksa spoja L s rodaminom B i auraminom O, dok konstantu stabilnosti kompleksa spoja L s fluoresceinom nije bilo moguće odrediti iako je vidljivo nastajanje kompleksa. Spoj L nije vezao antitumorski lijek timokinon u eksperimentalnim uvjetima korištenim u okviru ovog završnog rada. Usporedbom vrijednosti konstanti stabilnosti kompleksa spoja L s rodaminom B i auraminom O, vidljivo je da spoj L pokazuje podjednak afinitet prema vezanju obje boje i tvori s njima poprilično stabilne komplekse. Dobiveni eksperimentalni podaci upućuju na zaključak da fenantridinske podjedinice na donjem obodu kaliksarenskog derivata L pružaju dobro vezno mjesto za istraživane boje , te bi stoga ovaj derivat mogao imati velik potencijal za primjenu u teranostici, ukoliko bi se supstitucijom na gornjem obodu osigurala njegova vodotopljivost.Complexation of fluorescent dyes rhodamine B, auramine O, and fluorescein, as well as the antitumor drug thymoquinone with disubstituted phenanthridine derivative of calix[4]arene, 5,11,17,23- tetra-tert-butyl-25,27-(bis(6-phenanthridinemethoxy)-26,28-dihydroxycalix[4]arene (L), was studeied by means of spectrophotometric titrations in the solvent system acetonitrile/dichloromethane, at room temperature. By processing the experimental data, the stability constants of the complexes of compound L with rhodamine B and auramine O were determined, while the stability constant of the complex of compound L with fluorescein could not be determined, although the formation of the complex was noted. Compound L did not bind the antitumor drug thymoquinone under the experimental conditions used in this bachelor thesis. Comparison of the values of the stability constants of the complexes of compound L with rhodamine B and auramine O, showed that compound L exibits equal affinity for the binding of both dyes and forms fairly stable complexes with them. The obtained experimental data lead to the conclusion that phenanthridine subunits on the endo rim of the calixarene derivative L provide a good binding site for the tested dyes, and therefore this derivative, modified at the exo rim with substituents that would ensure its solubility in water, could have great potential for application in theranostics
f Sysimbrium officinale (L.) Scop.: glucosinolates and their microwave-assisted degradation : diploma thesis
No full textGlukozinolati, β-tioglukozidni-N-hidroksisulfati s varijabilnim bočnim lancem, su sekundarni metaboliti koji se sintetiziraju iz aminokiselina. Glukozinolati su kemijski stabilni i biološki neaktivni spojevi, a njihovom razgradnjom nastaje niz različitih biološki aktivnih razgradnih produkata. Razgrađuju se enzimskim, termičkim i kemijskim putem. U ovom radu primijenjene su različite metode izolacije uključujući hidrodestilaciju u modificiranoj aparaturi po Clevengeru, autolizu te mikrovalnu destilaciju i ekstrakciju kako bi istražili termičku, enzimsku i mikrovalovima potpomognutu razgradnju glukozinolata. Cilj rada bio je izolirati i identificirati hlapljive sumporove spojeve iz strižuše (Sisymbrium officinale (L.) Scop.). Strižuša, biljna vrsta porodice Brassicaceae, sabrana je u Splitu te na području rijeke Krke u svibnju 2019. godine. Glukozinolati su identificirani indirektno, GC-MS analizom njihovih razgradnih produkata te direktno HPLC-DAD analizom desulfatiziranih glukozinolata. U svim biljnim dijelovima strižuše (korijen, stabljika, list, cvijet), s oba područja, identificirana su tri glukozinolata glukoputranjivin (0,68-16,00 µmol/g), 4-hidroksiglukobrasicin (0,035-2,732 µmol/g) i glukobrasicin (0,244-6,397 µmol/g). U korijenu biljke još su identificirani glukosinalbin, 4-metoksiglukobrasicin i neoglukobrasicin. Hlapljivi spojevi analizirani GC-MS analizom ukazuju da je najzastupljeniji izopropil- izotiocijanat, kao razgradni produkt glukoputranjivina.Glucosinolates, β-thioglucoside-N-hydroxysulphates with variable side chains, are secondary metabolites synthesized from amino acids. Glucosinolates are chemically stable and biologically inactive compounds, and their degradation produces a number of different biologically active degradation products. They can be degraded enzymatically, thermally and chemically. Different isolation methods have been applied in this work, including hydrodistillation in the modified Clevenger apparatus, autolysis, and microwave distillation and extraction in order to investigate the thermal, enzymatic, and microwave- assisted glucosinolate degradation. The aim of the study was to isolate and identify volatile sulfur compounds from the hedge mustard (Sisymbrium officinale (L.) Scop.). Hedge mustard, a plant species of the Brassicaceae family, was collected in Split and in the Krka River area during May 2019. Glucosinolates were identified indirectly by GC-MS analysis of their degradation products and directly by HPLC-DAD analysis of desulfated glucosinolates. In all plant parts of the hedge mustard (root, stem, leaf, flower), in both areas, three glucosinolates were identified: glucoputranjivin (0.68-16.00 µmol/g), 4-hydroxyglucobrassicin (0.035-2.732 µmol/g) and glucobrassicin (0.244-6.397 µmol/g). Furthermore, glucosinalbin, 4- methoxyglucobrassicin and neoglucobrassicin were also identified at the root of the plant. The volatile compounds analyzed by GC-MS analysis indicate that the most common degradation product is isopropyl isothiocyanate, as the breakdown product of glucoputranjivin
Determination of cadmium concentration in enriched plant lepidium sativum L. usingatomic absorption spectroscopy : bachelor thesis
No full textBiljka Lepidium sativum L. je tijekom ranijih istraživanja izdvojena kao mogući hiperakumulator kadmija. Na zapadu se često koristi u prehrani radi dobrih svojstava, izdržljivosti i lakog uzgoja. Atomska apsorpcijska spektroskopija je analitička tehnika koja omogućava lako kvantitativno određivanje metala u uzorku. U ovom radu je prikazan uzgoj biljke Lepidium stativum L. uz zalijevanje različitim koncentracijama kadmija, a zatim je prikazana metoda pripreme biljnog materijala za analizu atomskim apsorpcijskim spektrometrom. Koristeći se spomenutim uređajem određena je koncentracija kadmija akumulirana u biljci. Analizom je utvrđeno da je biljka Lepidium sativum L. zaista dobar akumulator kadmija te da njena sposobnost akumulacije raste s koncentracijom kadmija u tlu.The plant Lepidium sativum L. was singled out during previous research as a possible hyperaccumulator of cadmium. In the West, it is often used in the diet for its good properties, durability and ease of cultivation. Atomic absorption spectroscopy is an analytical technique that allows easy quantitative determination of metals in a sample. This paper describes cultivation of the plant Lepidium stativum L., its watering using different concentrations of cadmium, and the method of preparation of plant material for analysis by atomic absorption spectrometer. The concentration of cadmium accumulated in the plant was determined using the mentioned device. The analysis showed that the plant Lepidium sativum L. is, indeed, a good accumulator of cadmium and its ability to accumulate it increases with the concentration of cadmium in the soil