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Comparison of the profiles of volatile compounds in sea fennel essential oils and the volatile compounds in their hydrolates obtained by various extraction methods : diploma thesis
No full textCilj diplomskog rada bio je izolirati i identificirati spojeve eteriĉnih ulja motra (Crithmum maritimum L.) i pripadajućih hidrolata biljaka prikupljenih s podruĉja Bresta u Francuskoj i Ţaborića u Hrvatskoj. Izolacija hlapljivih spojeva iz eteriĉnih ulja provedena je vodenom destilacijom u aparaturi po Clevengeru, dok je analiza hlapljivih spojeva hidrolata podrazumijevala primjenu metode mikroekstrakcije vršnih para na ĉvrstoj fazi i ekstrakcije tekuće- tekuće korištenjem diklormetana. Za analizu svih uzoraka korišten je sustav plinske kromatografije- spektrometrije masa (GC-MS), koji omogućava precizno razdvajanje i identifikaciju spojeva. U eteriĉnom ulju motra iz Bresta najzastupljeniji spojevi su dilapiol (62,10%), timil metil eter (18,00%) i γ-terpinen (9,88%), dok su u eteriĉnom ulju motra iz Ţaborića najzastupljeniji spojevi limonen (62,85%), sabinen (13,13%) i α-pinen (3,51%). Analizom hidrolata iz Bresta metodom mikroekstrakcije vršnih para na ĉvrstoj fazi (SPME) kao dominantni spojevi istiĉu se dilapiol (60,81%) i timil metil eter (14,84%), a u hidrolatu iz Šibenika (Ţaborić) dobivenom istom metodom dominiraju terpinen-4-ol (47,46%) i (Z)- karveol (8,01%). Hidrolati su takoĊer pripremljeni za analizu ekstrakcijom tekuće- tekuće s diklormetanom pri ĉemu se analizom u hidrolatu iz Bresta istaknuo dilapiol (85,81%) visokim udjelom, a u hidrolatu iz Ţaborića najzastupljeniji spoj je terpinen-4-ol (23,47%). Rezultati ovog istraţivanja pokazali su postojanje razlika u sastavu eteriĉnih ulja i hidrolata motra prikupljenih na dvije lokacije, što ukazuje da razliĉiti okolišni uvjeti doprinose razlikama u kemijskom sastavu istih biljaka. Ove razlike u sastavu mogu imati vaţne implikacije za primjenu motra u prehrambenoj industriji, kozmetici i medicini, ovisno o specifiĉnim svojstvima prisutnih spojeva. Dobiveni podaci pruţaju temelj za daljnja istraţivanja i potencijalni razvoj novih proizvoda na bazi motra.The aim of this work was to isolate and identify the compounds of the essential oils of sea fennel (Crithmum maritimum L.) and associated hydrolates of plants collected from the area of Brest in France and Ţaborić in Croatia. Isolation of volatile compounds from essential oils was performed by water distillation in a Clevenger apparatus, while the analysis of volatile hydrolate compounds was performed by solid-phase microextraction methods of peak vapors on the solid phase and liquid-liquid extraction using dichloromethane. A gas chromatography-mass spectrometry (GC-MS) system was used to analyze all samples, allowing precise separation and identification of the compounds. In the essential oil of sea fennel from Brest, the most abundant compounds are dillapiol (62,10%), thymyl methyl ether (18,00%) and γ-terpinene (9,88%), while in the essential oil of sea fennel from Šibenik (Ţaborić) the most abundant compounds are limonene (62,85%), sabinene (13,13%) and α- pinene (3,51%). The analysis of the hydrolate from Brest obtained by solid-phase microextraction method (SPME) shows that dillapiol (60,81%) and thymyl methyl ether (14,84%) are the dominant compounds, while in the hydrolate from Ţaborić obtained by the same method terpinene-4-ol (47,46%) and (Z)-carveol (8,01%) dominate. The hydrolates were also prepared for analysis by liquid-liquid extraction with dichloromethane, whereby the analysis revealed the compound dillapiol (85,81%) with a high percentage in the hydrolate from Brest, and the most abundant compound in the hydrolate from Ţaborić was terpinene-4- ol (23,47%). The results of this study show that there are differences in the composition of the essential oils and hydrolates of sea fennel collected from two locations, suggesting that different environmental conditions contribute to differences in the chemical composition of the same plants. These differences in composition may have important implications for the use of sea fennel in the food industry, cosmetics and medicine, depending on the specific properties of the compounds present. The data obtained will form a basis for further research and the possible development of new products based on sea fennel
Influence of zeolite saturated with Fe-ions and Fe, S-ions on the heat of hydration of cement CEM I : bachelor thesis
No full textU radu je ispitivan utjecaj prirodnog zeolita tipa klinoptilolita, te zeolita zasićenog Fe-ionima i Fe,S-ionima na toplinu hidratacije portland cementa, CEM I. Ispitivanje topline hidratacije provedeno je u trajanju od 48 sati hidratacije upotrebom diferencijalnog mikrokalorimetra pri 20 °C i uz omjer voda/cement, V/C = 0,5 te uz omjer voda/kruto V/K = 0,5 za cemente uz dodatke prirodnog zeolita, te zeolita zasićenog Fe-ionima i Fe, S-ionima. Za prvih 48 sati hidratacije pomoću raĉunalnog programa za svaki sat odreĊena je toplina hidratacije, brzina oslobaĊanja topline i stupanj proreagiranosti za uzorke bez i uz dodatak zeolita zasićenog Fe-ionima i Fe, S-ionima. Nakon analize podataka utvrĊeno je da dodatci ne mijenjaju mehanizam hidratacije, ali imaju utjecaj na vrijednosti praćenih parametara hidratacije koje su bitno niţe u odnosu na cement bez dodataka. Dodatak prirodnog zeolita, te zeolita zasićenog Fe-ionima ne utjeĉe na vrijeme pojave maksimuma krivulje topline hidratacije, dok se uz zeolit zasićen Fe i S-ionima maksimum pomiĉe prema kasnijim vremenima što upućuje na kasniju pojavu poĉetka i kraja vezanja cementne paste uz ovaj dodatak.The paper investigated the influence of natural zeolite of the clinoptilolite type and zeolite saturated with Fe-ions and Fe, S-ions on the heat of hydration of Portland cement, CEM I. The heat of hydration test was carried out during 48 hours of hydration using a differential microcalorimeter at 20 °C and with a water/cement ratio of V/C = 0.5 and with a water/solid ratio of V/K = 0.5 for cements with additions of natural zeolite and zeolite saturated with Fe-ions and Fe, S-ions. For the first 48 hours of hydration, a computer program was used to determine the heat of hydration, the rate of heat release and the degree of reactivity for samples without and with the addition of zeolite saturated with Fe-ions and Fe, S-ions. After analyzing the data, it was determined that the additives do not change the hydration mechanism, but they have an impact on the values of the monitored hydration parameters, which are significantly lower compared to cement without additives. The addition of natural zeolite and zeolite saturated with Fe-ions does not affect the time of the maximum appearance of the heat of hydration curve, while with zeolite saturated with Fe and S-ions, the maximum moves to later time, which indicates a later appearance of the beginning and end of cement paste binding with this addition
Influence of selenium on glucosinolate profile in broccoli sprouts : master thesis
No full textGlukozinolati su produkti sekundarnog metabolizma identificirani u preko 16 različitih biljnih porodica od kojih je najznačajnija porodica Brassicaceae koja uključuje često korišteno povrće u ljudskoj prehrani. U biljkama se nalaze u odvojenim odjeljcima od enzima mirozinaze koja cijepa ove inače kemijski stabilne spojeve na razgradne produkte poput tiocijanata, izotiocijanata, nitrila i indola. Zbog zabilježenog biološkog djelovanja produkata razgradnje, predmet su mnogih istraživanja u posljednje vrijeme. Brassica oleracea var. italica, poznatija kao brokula, jedno je od najpopularnijih vrsta povrća. Hidroponski uzgojeno povrće u fazi klica za svakodnevnu konzumaciju sve je više u upotrebi. Predmet istraživanja ovoga radavsu klice brokule uzgajane u čistoj vodi te različitim koncentracijama selenija: 1 ppm, 2,5 ppm, 5 ppm, 7,5 ppm i 10 ppm s ciljem praćenja utjecaja na profil glukozinolata. Glukozinolati su izolirani, prevedeni u desulfo-oblik te analizirani UHPLC-DAD-MS/MS tehnikom. Analizom je utvrđena prisutnost 12 različitih glukozinolata: progoitrin, glukonapoleiferin, glukoalisin, glukonapin, glukokohlearin, 4-hidroksiglukobrasicin, glukobrasikanapin, glukobrasicin, glukoberteroin, glukonasturcin, 4-metoksiglukobrasicin i neoglukobrasicin. Uočena je dominantna količina glukonapina i glukobrasikanapina s maksimumima od 67,31 µmol/g i 36,14 µmol/g pri 5 ppm selenija. Glukoberteroin je uočen samo u tragovima. Povišene koncentracije selenija negativno su utjecale na rast brokule te su također utjecale na profil glukozinolata u različitim uzorcima. Dva uzorka klica brokule uzgajanih u koncentaciji selenija od 5 ppm i 7,5 ppm podvrgnuta su reakciji s enzimom mirozinazom da bi se dobili razgradni produkti glukozinolata koji su identificirani GC-MS-om. Identificirana su dva nitrila: benzenpropanonitril i 4,5-epitiopentanonitril. Drugi cilj eksperimenta je bio ispitati hoće li brokula kroz sedam dana apsorbirati dio selenija zbog kemijske sličnosti i obilja u kojem je rasla te ga ugraditi u strukturu svojih glukozinolata. Niti jedan selenoglukozinolat ili selenometionin-izvedeni glukozinolat nije detektiran niti su detektirani njihovi produkti razgradnje.Glucosinolates are products of secondary metabolism identified in over 16 different plant families, the most significant of which is the Brassicaceae family, which includes vegetables often used in human nutrition. In plants, glucosinolates are found in special compartments separated from the myrosinase enzyme, which cleaves these otherwise chemically stable compounds into degradation products such as thiocyanate, isothiocyanate, nitrile and indole. Due to the recorded biological activity of degradation products, they have been the subject of many recent researhces. Brassica oleracea var. italica, better known as broccoli, is one of the most popular types of vegetables. Hydroponically grown vegetables sprouts for everyday consumption are being increasingly used. In this work, broccoli sprouts were grown in clean water with different concentrations of selenium: 1 ppm, 2.5 ppm, 5 ppm, 7.5 ppm and 10 ppm to monitor its influence on the glucosinolate profile. Glucosinolates were isolated, converted into desulfo-form and analyzed by UHPLC-DAD-MS/MS technique. The analysis determined the presence of 12 different glucosinolates: progoitrin, gluconapoleiferin, glucoalisin, gluconapin, glucocochlearin, 4-hydroxyglucobrassicin, glucobrassicannapin, glucobrassicin, glucoberteroin, gluconasturtin, 4-methoxyglucobrassicin and neoglucobrassicin. A dominant amount of gluconapin and glucobrassicanapin was observed with maxima of 67.31µmol/g and 36.14 µmol/g, respectively, at a selenium concentration of 5ppm. Glucoberteroin was observed only in traces. Elevated concentrations of selenium had a negative effect on the growth of broccoli and also affected the profile of glucosinolates in different samples. Two samples of broccoli sprouts grown in selenium concentrations of 5 ppm and 7.5 ppm were subjected to reaction with the myrosinase enzyme to obtain glucosinolate degradation products that were identified by GC-MS. Two nitriles were identified: benzenepropanonitrile and cyano-3,4-epithiobutane. The second goal of the experiment was to examine whether the broccoli will absorb part of the selenium in seven days due to the chemical similarity and abundance in which it grew and incorporate it into the structure of its glucosinolates. No selenoglucosinolate or selenomethionine-derived glucosinolates were detected, nor their degradation products
Xanthine oxidase and from nature isolated inhibitors of this enzyme : bachelor thesis
No full text: Cilj ovog završnog rada bio je pregled dostupne znanstvene literature na temu inhibicije enzima ksantin-oksidaze prirodnim spojevima izoliranim iz biljaka. Ksantin-oksidaza je enzim koji ima važnu ulogu u metabolizmu purinskih baza i samim tim u patogenezi gihta. Obzirom da lijekovi koji se koriste u liječenju ove bolesti sadrže i stanovite nuspojave neprestalno se traže iz prirode izolirani inhibitori ovog enzima s ciljem moguće prevencije i / ili tretmana gihta. Kao izvori podataka koristile su se dostupne relevantne znanstvene baze podataka Web of Science Core Collection i Scopus. Pregledom literature utvrđen je veliki broj objavljenih radova na temu inhibicije enzima ksantin oksidaze ekstraktima i spojevima koji ulaze u sastav ekstrakata biljaka. Rezultati su pokazali da su flavonoidi izolirani iz biljnih ekstrakata izvrstan izvor spojeva s inhibicijskim potencijalom na enzim ksantin-oksidazu.The aim of this study was to review available scientific literature on the inhibition of xanthine oxidase enzymes by natural compounds isolated from plants. Xanthine oxidase is an enzyme that plays an important role in the metabolism of purine bases and hence in the pathogenesis of gout. Since medicines used to treat this disease also contain certain side effects, isolated inhibitors of this enzyme are continuously sought from nature with the aim of possible prevention and/or treatment of gout. The relevant scientific databases Web of Science Core collection and Scopus were used as data sources. The literature review revealed that a large number of papers on the inhibition of xanthine oxidase enzymes by extracts and compounds forming part of plant extracts have been published to date. The results showed that flavonoids isolated from plant extracts are an excellent source of compounds with inhibitory potential on xanthine oxidase enzyme
Hydrogen evolution reaction on Ni-Mo cathode : bachelor thesis
No full textMetodama cikličke voltametrije, kvazipotenciostatske linearne polarizacije i elektrokemijske impedancijske spektroskopije proučavana je elektrokatalitička aktivnost Ni-28Mo elektrode za reakciju razvijanja vodika. Mjerenja su izvedena u 0.5 mol dm -3 otopini NaOH pri temperaturi od 20 ̊C. Ciklički voltamogram snimljen je u širokom području potencijala i jasno ukazuje na potencijale pri kojima dolazi do nastanka te redukcije metalnih oksida i hidroksida. Elektrokatalitička aktivnost elektrode iskazana je katalitičkim parametrima gustoće struje izmjene j 0 i Tafelovog katodnog nagiba b k koji su određeni kvazipotenciostatskom linearnom polarizacijom i elektrokemijskom impedancijskom spektroskopijom. Uz pomoć modificiranog Randlesovog ekvivalentnog električnog kruga matematički su usklađeni spektri dobiveni elektrokemijskom impedancijom, a hrapavost elektrode određena je iz vrijednosti kapaciteta dvostrukog sloja izračunate upotrebom Brugove jednadžbe. Dobiveni rezultati impedancije pokazali su dobro slaganje s rezultatima kvazipotenciostatske linearne polarizacije, a Tafelovi nagibi potvrđuju da se reakcija razvijanja vodika odvija po Volmer-Heyrovski mehanizmu te da je brzina ukupne reakcije određena reakcijom Heyrovskog.Cyclic voltammetry, quasipotentiostatic linear polarization and electrochemical impedance spectroscopy were methods used in the study of electrocatalytic activity of the Ni-28Mo electrode for the hydrogen evolution reaction. The measurements were performed in a 0.5 mol dm -3 NaOH solution at a temperature of 20 ̊C. The cyclic voltammogram was recorded over a wide range of intervals and clearly shows the potentials that lead to the formation and reduction of metal oxides and hydroxides. Electrocatalytic activity of the electrode is expressed by the catalytic parameters of the current density exchange j 0 and the Tafel cathodic slope b k which were determined by quasipotentiostatic linear polarization and electrochemical impedance spectroscopy. Using a modified Randles equivalent electric circuit, spectra obtained by electrochemical impedance were matched, and roughness of the electrode was determined from the value of the double layer capacity using Brug equation. The obtained impedance results were matching with the results of quasipotentiostatic linear polarization, and the Tafel slopes confirmed that the hydrogen evolution reaction takes place according to Volmer-Heyrovski mechanism and that the speed of the overall reaction is determined by the Heyrovski reaction
Antimicrobial effect of Padina pavonica and selected phenolic compounds of pathogenic bacteria : diploma thesis
No full textHrana koja se stavlja na tržište mora biti dobre kvalitete i zdravstveno ispravna. Na putovanju „od polja do stola“ odnosno prije nego hrana dođe do potrošača, uslijed kvarenja izgubi se 1/3 od ukupno proizvedene količine. Zahtjevi za sigurnom i kvalitetnom hranom rastu kao i briga zbog učestale uporabe sintetskih konzervansa koji to osiguravaju, stoga se sve veća pažnja pridaje prirodnim konzervansima kao alternativi. Potencijalne prirodne konzervanse predstavljau i morske alge zbog svog kemijskog sastava. Alge sadrže spojeve s visokom biološkom aktivnošću od kojih se najviše ističu fenolni spojevi, sekundarni biljni metaboliti koji su jedna od najvećih skupina fitokemikalija koji pridonose antimikrobnom i antioksidacijskom djelovanju algi. U ovom istraživanju ispitana je antimikrobna aktivnost smjese ekstrakta smeđe alge Padina pavonica i odabranih fenolnih spojeva (vanilinska kiselina, katehin, rutin, apigenin i oleuropein) na patogene bakterije (Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Enterococcus faecalis, Escherichia coli i Salmonella enteritidis). Ispitivanje je provedeno metodama određivanja minimalne inhibitorne koncentracije (engl. Minimum inhibitory concentration, MIC) i određivanja minimalne baktericidne koncentracije (engl. Minimum bactericidal concentration, MBC). Interakcijski antimikrobni učinak između ekstrakta i spoja u smjesi određen je računanjem frakcijskog inhibitornog koncentracijskog indeksa (engl. Fractional Inhibitory Concentration Index, FICI). Ekstrakt smeđe alge P. pavonica s MIC i MBC vrijednosti od 2,5 mg/mL, pokazao je najbolji antimikrobni učinak protiv bakterije S. aureus, dok su MIC i MBC vrijednosti prema ostalim bakterijama iznosile 5 ili 10 mg/mL. Sve binarne smjese ekstrakta P. pavonica i odabranih fenolnih spojeva pokazale su vrlo dobru antimikrobnu aktivnost, ali su uglavnom ukazivale na aditivno djelovanje. Najlošiji interakcijski učinak i najveće FICI vrijednosti (≥ 2) zabilježene su za smjese ekstrakta P. pavonica i katehina, rutina i vanilinske kiseline prema L. monocytogenes.The food placed on the market must be of good quality and healthy. On the way "from field to table", i.e. before the food reaches the consumer, one third of the total production quantity is lost due to spoilage. Demand for safe, high-quality food is growing, as is concern about the frequent use of synthetic preservatives to ensure this. Because of their chemical composition, algae are also suitable natural preservatives. Algae contain compounds with high biological activity, the best known of which are phenolic compounds, secondary plant compounds that represent one of the largest groups of phytochemicals contributing to the antimicrobial and antioxidant activity of algae. In this study, the antimicrobial activity of a mixture of Padina pavonica algae extract and selected phenolic compounds (vanillic acid, catechin, rutin, apigenin, and oleuropein) against pathogenic bacteria (Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Enterococcus faecalis, Escherichia coli, and Salmonella enteritidis) was tested. The test was performed using methods of determining the minimum inhibitory concentration (Minimum inhibitory concentration, MIC) and determining the minimum bactericidal concentration (Minimum bactericidal concentration, MBC) methods. The antimicrobial interaction between the extract and the compound in the mixture was determined by calculating the fractional inhibitory concentration index (FICI). The extract of P. pavonica algae mixture with MIC and MBC values of 2.5 mg/mL showed the best antimicrobial activity against the S. aureus bacteria, while the MIC and MBC values for other bacteria were 5 or 10 mg/mL. All binary mixtures of P. pavonica extract and selected phenolic compounds showed very good antimicrobial activity, but mostly indicated an additive effect. The worst interaction effect and the highest FICI values (≥ 2) were observed for mixtures of P. pavonica extract and catechin, rutin, and vanillic acid against L. monocytogenes
Metabolomic studies of the Antarctic lichen Stereocaulon glabrum. Study of the matabolic response to rehydratation and sunlight after 15 years from collection : diploma thesis
No full textNa Antarktici, gdje vladaju ekstremni uvjeti, mogu preživjeti samo organizmi razvijenih strategija preživljavanja. Lišajevi, kao simbiotski organizmi, razvili su izvanredne mehanizme prilagodbe kako bi preživjeli te teške uvjete. U ovom radu istražuje se metabolički odgovor antarktičkog lišaja Stereocaulon glabrum na rehidraciju i izloženost sunčevim zrakama nakon 15 godina od trenutka prikupljanja. Uzorci lišaja, prikupljeni s antarktičkog područja, rehidrirani su pod kontroliranim laboratorijskim uvjetima i izloženi sunčevoj svjetlosti tijekom 2 i 9 dana. Dodatno, provedena je analiza dehidriranog S. glabrum kako bi se dobio metabolički profil nakon 15 godina čuvanja u mraku i pri konstantnoj temperaturi. U ovom radu korišten je moćni tandem LC-MS/MS kao metoda za kvalitativnu i kvantitativnu analizu sekundarnih metabolita. Ukupno su identificirana 23 sekundarna metabolita, od kojih su glavni lobarinska kiselina, strepsilin, burgeanska kiselina i atranol.On Antarctica, where extreme conditions are present, only organisms that developed survival strategies can survive. Lichens, as symbiotic organisms, have developed remarkable adaptability strategies to withstand these harsh conditions. This study explores the metabolic response of the Antarctic lichen Stereocaulon glabrum to rehydration and sunlight exposure after being preserved for 15 years since its collection. The lichen samples, collected from the Antarctic region, were rehydrated under controlled laboratory conditions and subjected to sunlight exposure for 2 and 9 days, respectively. In addition to that, analysis of dehydrated S. glabrum was done to obtain the metabolic profile after 15 years of being kept in dark and at constant temperature. For this study, a powerful tandem LC-MS/MS was used for the qualitative, as well as the quantitative, analysis of the secondary metabolites. In total, 23 secondary metabolites were identifed of which the major are lobaric acid, strepsilin, bourgeanic acid and atranol
ANALYSIS OF VOLATILE COMPOUNDS IN THE PROCESS OF COUNERFEITING HONEY USING MAPLE SYRUP, SUGAR AND FLOWER POLLEN : diplom athesis
No full textU ovom radu analiziran je kemijski sastav hlapljivih spojeva u procesu patvorenja meda. Za analizu su uzeti uzorci cvjetne peludi, meda, javorovog sirupa, saharozne probe te smjesa cvjetne peludi i javorovog sirupa i smjesa cvjetne peludi i saharozne probe. Med i cvjetna pelud koji su bili osnova za istraživanje patvorenja uzeti su s podruĉja Slavonskog Broda. Za patvorenje je korišten komercijalni javorov sirup i komercijalni šećer pomoću kojeg se u laboratoriju napravila saharozna proba. Hlapljivi spojevi izolirani su metodom mikroekstrakcije vršnih para na krutoj fazi ( HS-SPME) korištenjem sivog vlakna s ovojnicom divinilbenzen/karboksen/polidimetilsiloksan (DVB/CAR/PDMS). Dobiveni uzorci analizirani su vezanom tehnikom plinska kromatografija-spektrometrija masa (GC-MS). Analizom patvorenog meda naĉinjenog od smjese cvjetne peludi i javorovog sirupa te smjese cvjetne peludi i saharozne probe detektiran je niz spojeva koji su analizom detektirani i u medu.In this study, the chemical composition of volatile compounds in the process of honey adulteration was analysed. Samples of flower pollen, honey, maple syrup, sucrose and a mixture of flower pollen and maple syrup and a mixture of flower pollen and sucrose were taken for the analysis. The honey and flower pollen, which formed the basis for the adulteration investigation, came from the Slavonski Brod region. Commercial maple syrup and commercial sugar were used for adulteration, and a sucrose sample was prepared in the laboratory. The volatile compounds were isolated by the solidphase microextraction method (HS-SPME), using a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) coated fibre. The obtained samples were analyzed by gas chromatography-mass spectrometry (GC-MS). By analyzing the adulterated honey made from a mixture of flower pollen and maple syrup, as well as a mixture of flower pollen and sucrose, a series of compounds were detected that were also found in the honey alaysis
PHYTOCHEMICAL PROFILE OF ESSENTIAL OILS AND HYDROLATES OF LAUREL, ROSEMARY, GOLDEN SAMPHIRE AND SEA FENNEL : diplom athesis
No full textCilj ovog rada je bio odrediti kemijski sastav i sadržaj hlapljivih spojeva u eteričnim uljima i hidrolatima biljaka lovora (Laurus nobilis L.), ružmarina (Rosmarinus officinalis L.), primorskog omana (Inula crithmoides L.) i motra (Crithmum maritimum L.) sakupljenih u proljeće na području srednje Dalmacije. Eterična ulja i hidrolati su dobiveni vodenom destilacijom u aparaturi po Clevengeru. Ulja su potom izravno analizirana u vezanom sustavu plinska kromatografija - spektrometrija masa (GC-MS), a vršne pare uzoraka hidrolata su prikupljene mikroekstrakcijom vršnih para na čvrstoj fazi (HS-SPME) te analizirane u GC-MS-u. Najzastupljenije komponente eteričnog ulja (EO) lovora su 1,8-cineol, α-terpinil acetat, metil eugenol, sabinen, α-terpineol i α-pinen, dok su najzastupljenije komponente njegovog hidrolata 1,8-cineol, α-terpinil acetat, α-terpineol, eugenol, terpinen-4-ol i metil eugenol. Najzastupljenije komponente EO ružmarina su α-pinen, 1,8-cineol, verbenon, bornil acetat i borneol, dok su najzastupljenije komponente njegovog hidrolata 1,8-cineol, karvon, verbenon, bornil acetat, borneol, α-terpineol i kamfor (7,43%). Najzastupljenije komponente EO primorskog omana su p-cimen, 8,9-dehidrotimol metil eter, p- cimen-7-ol, 2,4-dimetil izoheksil benzoat i α-felandren (5,90%), dok su najzastupljenije komponente njegovog hidrolata 8,9-dehidrotimol metil eter, 8,9-dehidrotimol, p-cimen, -8,9-dehidro-4-hidroksitimol dimetil eter i benzenacetaldehid. Najzastupljenije komponente EO motra su limonen, sabinen i (E)-β- ocimen, dok su najzastupljenije komponente njegovog hidrolata terpinen-4-ol, limonen, cis-p-ment-2-en- 1-ol i cis-sabinen hidrat.The aim of this work was to determine the chemical composition and content of volatile compounds in essential oils and hydrolates of plants laurel (Laurus nobilis L.), rosemary (Rosmarinus officinalis L.), golden samphire (Inula crithmoides L.) and sea fennel (Crithmum maritimum L.) collected in the spring in the area of central Dalmatia. Essential oils and hydrolates were obtained by water distillation in a Clevenger apparatus. The oils were then directly analyzed in a coupled gas chromatography-mass spectrometry (GC-MS) system, and the peak vapors of the hydrolate samples were collected by microextraction of the peak vapors on the solid phase (HS-SPME) and analyzed in GC-MS. The most abundant components of the essential oil (EO) of laurel are 1,8-cineole, α-terpinyl acetate, methyl eugenol, sabinene, α-terpineol and α-pinene, while the most abundant components of its hydrolate are 1,8-cineole, α-terpinyl acetate, α-terpineol, eugenol, terpinen-4-ol and methyl eugenol. The most abundant components of rosemary EO are α-pinene, 1,8-cineole, verbenone, bornyl acetate and borneol, while the most abundant components of its hydrolate are 1,8-cineole, carvone, verbenone, bornyl acetate, borneol, α-terpineol and camphor (7,43%). The most abundant components of EO of golden samphire are p-cymene, 8,9- dehydrothymol methyl ether, p-cymen-7-ol, 2,4-dimethyl isohexyl benzoate and α-phellandrene (5,90%), while the most abundant components of its hydrolate 8,9-dehydrothymol methyl ether, 8,9-dehydrothymol, p-cymene, -8,9-dehydro-4-hydroxythymol dimethyl ether and benzeneacetaldehyde. The most abundant components of the EO sea fennel are limonene, sabinene and (E)-β-ocimene, while the most abundant components of its hydrolate are terpinen-4-ol, limonene, cis-p-menth-2-en-1-ol and cis-sabinene hydrate
TWO-STAGE REMOVAL OF ZINC FROM AN AQUEOUS SOLUTION CONTAINING 100mg Zn/L BY CHEMICAL PRECIPITATION AND SORPTION ON BIOSORBENTS : bachelor thesis
No full textVažnost vode za život na Zemlji dobro je poznata, međutim unatoč tome vode u prirodi se svakodnevno onečišćuju različitim štetnim tvarima porijeklom iz antropogenih izvora. Najveća prijetnja dolazi iz industrije gdje industrijske otpadne vode, ukoliko se prije ispuštanja ne obrade, ozbiljno narušavaju kakvoću vodnih ekosustava. Otpadne vode iz industrije te rudarenja visoko su opterećene teškim metalima koji ugrožavaju sve žive organizme. Iz toga su razloga istraživanja sve više usmjerena na razvijanje postojećih metoda obrade voda te pronalaženje prirodnih lako dostupnih materijala koji su ekonomski i ekološki prihvatljivi. U ovome završnom radu provedeno je uklanjanje cinka iz vodene otopine koncentracije 100 mg Zn/L kemijskim taloženjem uz neutralizaciju različitim taložnim sredstvima do pH područja 7,0-7,5; 8,0-8,5 i 9,0-9,5, a potom sorpcijom na biosorbensima (koštice maslina, trešanja i višanja). Već u prvom stupnju obrade kemijskim taloženjem uz neutralizaciju do pH=9,0-9,5 postignuta je izvrsna učinkovitost uklanjanja (≥ 99,55 %), s ostatnom koncentracijom cinka ispod maksimalno dopuštene (2 mg/L), dok je pri pH=7,0-7,5 i pH=8,0-8,5 za postizanje graničnih koncentracija trebalo provesti drugi stupanj obrade sorpcijom na biosorbensima.The importance of water for life on Earth is well known, but despite this, water in nature is polluted daily by various harmful substances originating from anthropogenic sources. The biggest threat comes from industry where industrial wastewaters, if not treated before discharge, seriously endanger the quality of water ecosystems. Wastewater from industry and mining is highly contaminated with heavy metals which are harmful for all living organisms. Therefore, research is increasingly focused on developing existing water treatment methods and finding natural, easily available materials that are economically and environmentally acceptable. In this thesis, the removal of zinc from contaminated water containing 100 mg Zn/L was carried out by chemical precipitation with neutralization using different precipitating agents to a pH range of 7.0-7.5; 8.0-8.5 and 9.0-9.5, followed by sorption on biosorbents (olive pits, cherry pits and sour cherry pits). Excellent removal efficiency (≥ 99.55%) was achieved already in the first stage of treatment by chemical precipitation with neutralization to pH=9.0-9.5, with the remaining zinc concentration below the maximum allowed (2 mg/L). At pHs 7.0-7.5 and 8.0-8.5, in order to achieve the discharge limit, it was necessary to perform second treatment stage by sorption on biosorbents