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Cytotoxic activity of sage (Salvia officinalis L.) and immortelle (Helichrysum italicum (Roth) G. Don.) essential oils : diploma thesis
No full textUzorci samoniklih biljaka, kadulje (lat. Salvia officinalis L.) i smilja (lat. Helichrysum italicum (Roth) G. Don.) sakupljeni su na području Dalmacije i Bosne i Hercegovine. Izolacija eteričnih ulja izvršena je postupkom hidrodestilacije u modificiranoj aparaturi po Clevengeru. Pretražnom elektronskom mikroskopijom na biljnom tkivu uočene su i fotografirane žlijezde u kojima biljka skladišti eterično ulje. Kemijski sastav eteričnih ulja određen je spregnutom instrumentalnom tehnikom koja povezuje plinsku kromatografiju i spektrometriju masa (GC-MS). In vitro citotoksična aktivnostog eteričnog ulja kadulje i eteričnog ulja smilja određena je na staničnoj liniji humanog dermalnog fibroblasta (HDF/Tert) i na MDA- MB-231 staničnoj liniji karcinoma dojke. Nakon tretiranja otopinama eteričnog ulja, vijabilnost stanica praćena je upotrebom MTS reagensa i mjerenjem apsorbancije pri 492 nm. Rezultati citotoksične aktivnosti otopina eteričnog ulja kadulje i eteričnog ulja smilja pokazuju nisku citotoksičnost na HDF/Tert stanice kože. Eterično ulje smilja na MDA-MB-231 staničnoj liniji karcinoma dojke pokazuje značajniju citotoksičnu aktivnost u odnosu na eterično ulje kadulje.Samples of two self-sown plants, sage (lat. Salvia officinalis L.) and immortelle (lat. Helichrysum italicum (Roth) G. Don.), were collected in Dalmatia and Bosnia and Herzegovina. Isolation of the plants essential oil was carried by a hydrodistillation process in a modified Clevenger apparatus. With scanning electron microscopy of plant tissue a plant's glands with stored microdroplets of oils were visualized. The chemical composition of the essential oils is determined by a coupled instrumental technique linking gas chromatography and mass spectrometry (GC-MS). In vitro cytotoxic activity of sage essential oil and immortelle essential oil was determined on human dermal fibroblast (HDF/Tert) cells line and MDA-MB- 231 breast cancer cells line. After treatment with the essential oil solutions, cell viability was tested using MTS reagents and measuring absorbance at 492 nm. Cytotoxic activity results show that solutions of sage essential oil and immortelle essential oil have a low cytotoxic effect on HDF / Tert skin cells. The immortelle essential oil tested on MDA-MB-231 cells line shows significantly higher cytotoxic activity than the sage essential oil
Preparation and characterization of polylactid acid/poly(ethylene-oxide) blends : diploma thesis
No full textSvrha ovog rada bila je pripremiti uzorke mješavina PLA/PEO te utvrditi mješljivost temeljem istraživanja interakcija PLA-a s PEO-om u mješavinama različitih sastava. Mješavine PLA/PEO različitih sastava pripremljene su na laboratorijskom ekstruderu pri čemu tijekom ekstrudiranja nije došlo do toplinske razgradnje. Diferencijalna pretražna kalorimetrija, DSC, primijenjena je za određivanje karakterističnih prijelaza čistih polimera i njihovih mješavina, s ciljem utvrđivanja mješljivosti komponenata u mješavini. Staklište PLA, kao kriterij za procjenu mješljivosti, nije bilo moguće odrediti zbog preklapanja s endotermnim pikom taljenja PEO-a. Stoga su tališta čistih polimera promatrana kao kriterij mješljivosti. Na temelju dobivenih rezultata može se zaključiti da su mješavine PLA/PEO djelomično mješljive, odnosno samo pri većem udjelu jedne (80/20) ili druge komponente u mješavini (20/80). Primjenom infracrvene spektroskopije s Fourierovom transformacijom, FTIR, potvrđeno je postojanje interakcija u mješavinama PLA/PEO. Najznačajniji pomaci karakterističnih vrpci uočeni su samo u mješavinama s većim udjelom jedne (80/20) ili druge komponente u mješavini (20/80).The purpose of this study was to prepare PLA/PEO blends and determine miscibility based on PLA interaction with PEO in blends of different composition. Blends of PLA/PEO of different compositions were prepared on the laboratory extruder without thermal degradation. Differential scanning calorimetry, DSC, was applied to determine the characteristic transitions of pure polymers and their blends in order to determine the miscibility of the components in the blend. Evaluation of miscibility with glass transition metod could not be applied to the PLA/PEO blend because the melting endothermic of PEO and the glass transition of PLA, T g of PLA, were overlapped. In these cases, the melting temperature, T m depression method can be used. From these results it can be concluded that PLA/PEO blends are partially miscible, or only in the higher proportion of one (80/20) or other component in the blend (20/80). Infrared Fourier transform spectroscopy, FTIR, confirmed the existence of interactions in the PLA/PEO blends. The most significant shifts of characteristic bands were observed only in blends with a higher proportion of one (80/20) or other component in the blend (20/80)
Isolation of volatile compounds of rosemary honey by ultrasonic extraction before and after heating : bachelor thesis
No full textMnogi spojevi biološkog i botaničkog podrijetla u medu nisu stabilni, naročito hlapljive tvari, a njihove se strukture mogu transformirati tijekom sazrijevanja meda, njegova skladištenja i zagrijavanja. U ovom radu se istraživao utjecaj zagrijavanja na sastav i sadržaj hlapljivih spojeva u medu od ružmarina. Uzorak meda se zagrijavao na 60 o C (2 sata) sa dodatkom vode. Hlapljivi spojevi ekstrahirani su pomoću pentan:dietil-etera = 1:2 (v/v) i diklormetanskog otapala postupkom ultrazvučne ekstrakcije (USE) pri sobnoj temperaturi. Ekstrakti su analizirani vezanim sustavom plinska kromatografija-masena spektrometrija (GC-MS). Dominantni spoj identificiran u oba ekstrakta dobivena nakon zagrijavanja meda na 60 o C je 5-hidroksimetilfurfural.Many compounds of biological and botanical origin in honey are not stable, particulary volatile substances, and their structures can be trandformed during honey maturation, storage and heating. In this paper the influence of heating on the composition and content of rosemary honey was investigated. The honey sample was heated up to 60 o C (2 hours) with the addition of water. Volatile compounds were extracted with pentane:diethyl ether = 1:2 (v/v) and dichloremethane using ultrasound assisted solvent extraction (USE) at room temperature. The extracts were analyzed by gas chromatography-mass spectrometry (GC-MS). The dominant compounds identified in both extracts after heating them up to 60 o C was 5-hydroxymethylfurfural
Fluoride-ion selective electrode and determination fluoride-review : bachelor thesisi
No full textJedna od najvaţnijih potenciometrijskih tehnika za praćenje fluorida su ionsko-selektivne elektrode. To su elektrode čiji je potencijal ovisan o koncentraciji samo jedne, odreĎene ionske vrste u otopini. Danas su razvijeni razni tipovi fluorid – ionsko selektivnih elektroda, a to su: elektrode s kristalnom membranom, elektrode s heterogenim membranama, elektrode sa nekristalnim membranama, elektrode s staklenom membranom, elektrode s mobilnim prenosiocem, elektrode za plinove i enzimske elektrode. U ovom radu dat je pregled novije literature za flourid ionsko selektivnu elektrodu (FISE) i odreĎivanja fluorida fluorid- ionsko selektivnim elektrodama.One of the main potenciometrics techniques for the fluorid determination are ion – selective electrodes. Those are electrodes that respond selectively to the particular ion in solution. Nowdays, many types of the fluoride – ion selective electrodes are developed, such as: crystal membrane electrodes, heterogeneous membrane electrodes, non - crystalline membrane electrodes, glass membrane electrodes, mobile carrier electrodes, gas and enzyme electrodes. This review describes recent literature on fluoride – ion selective electrodes and the determination of fluoride by fluoride-selective electrodes
A mass transfer analysis of competitive binding of Pb, Cd and Zn from binary systems onto a fixed zeolite bed : diploma thesis
No full textIspitano je uklanjanje kadmijevih i cinkovih iona na nepomičnom sloju prirodnog zeolita iz vodene otopine (Cd+Zn) koncentracijskog omjera Cd/Zn od 0,13 i 0,14, pri protocima od 1 i 2 mL/min. Prirodni zeolit klinoptilolit pokazao je dobru učinkovitost u uklanjanju Cd i Zn iona iz binarnog sustava pri ispitanim eksperimentalnim uvjetima. Dobiveni rezultati uspoređeni su s binarnim sustavom (Pb+Zn) za iste eksperimentalne uvjete. Utvrđen je efekt istiskivanja iona Zn iz strukture zeolita ionima Cd i Pb iz početne otopine. Zn je prekoračio svoju početnu koncentraciju za 1,2 puta u prisutnosti Cd te čak 2,3 puta u prisutnosti Pb. Efekt istiskivanja u sustavu (Pb+Zn) može se pripisati puno manjem hidratiziranom radijusu iona Pb u odnosu na ion Zn, a time i njegovu većem afinitetu. Istiskivanje u sustavu (Cd+Zn) bilo je iznenađujuće zbog vrlo sličnih fizikalno-kemijskih svojstava tih dvaju iona. Pri Cd/Zn = 0,14 te Pb/Zn = 0,19 i protoku od 1 mL/min u oba sustava utvrđeno je bolje vezanje iona Zn u odnosu na ione Cd i Pb, unatoč njegovu slabijem afinitetu. Tor ukazuje da je moguće preferencijalno vezanje iona Cd i Pb kontrolirati početnom koncentracijom iona Zn u binarnom sustavu. Ukupni koeficijent prijenosa tvari veći je za (Cd+Zn) nego za (Pb+Zn) sustav zbog manje izražene kompeticije i migracije iona, a time i manjeg otpora. Najsporiji stupanj je difuzija kroz film te ona kontrolira ukupnu brzinu procesa.The removal of cadmium and zinc ions onto fixed zeolite bed from (Cd+Zn) aqueous solution for the Cd/Zn concentration ratios of 0.13 and 0.14, and for the flow rates of 1 and 2 mL/min has been investigated. The natural zeolite clinoptilolite showed good efficiency in Cd and Zn removal from binary system, for examined experimental conditions. The obtained results have been compared with the (Pb+Zn) binary system for the same experimental conditions. The displacement of Zn ions from the zeolite structure by the Cd and Pb ions from the initial solution has been determined. The Zn exceeded its initial concentration up to 1.2 times in the presence of Cd, and up to 2.3 times in the presence of Pb. The displacement effect in the (Pb+Zn) system can be attributed to the much smaller hydrated radius of Pb ion, compared to the Zn ion, and thus to its higher affinity. The displacement in the (Cd+Zn) system was quite surprising due to very similar physicochemical properties of these two ions. In both systems, for Cd/Zn = 0.14 and Pb/Zn = 0.19 for flow rate of 1 mL/min, the better binding of Zn compared to Cd and Pb has been obtained despite its lower affinity. This is of great importance because it indicates that it's possible to control preferencial binding of Cd and Pb ions by the initial Zn ion concentration in binary systems. The overall mass transfer coefficient shows higher values for the (Cd+Zn) system compared to the (Pb+Zn) system, due to the reduced competition, ions migration and thus the lower resistance. The diffusion through the film is the slowest step responsible for the overall process rate
Coordination polymers and metal-organic frameworks - preparation and properties : bachelor thesis
No full textKoordinacijski polimeri i metalnoorganske mreţe su noviji materijali koji su se počeli razvijati krajem dvadesetog stoljeća. Temelje se na povezivanju iona metala s organskim ligandima. Razvoj istraţivanja koordinacijskih polimera je pojačan zbog razvoja dvaju srodnih područja: kristalnog inţenjerstva i supramolekulske kemije. Cilj ovog rada je objasniti što su metalnoorganske mreţe i koordinacijski polimeri, te objasniti njihove strukture, razlike izmeĎu 1D, 2D i 3D struktura i topologiju metalnoorganskih mreţa i koordinacijskih polimera. TakoĎer je cilj ovog rada opisati različite metode sinteze i razna svojstva koja posjeduju koordinacijski polimeri i metalnoorganske mreţe kao i primjenu tih svojstava.Coordination polymers and metal-organic frameworks are newer type of materials that are based on connecting metal ions with corresponding organic ligands. Their continuous development began at the end of the 20 th century. Development in study of coordination polymers is reinforced by two related areas: crystal engineering and supramolecular chemistry. The goal of this thesis is to explain what are coordination polymers and metal-organic frameworks, explain their structure, differences between 1D, 2D and 3D structures and to explain topology of metal- organic frameworks and coordination polymers. Furthermore, the goal is to describe different methods of synthesis and various properties of coordination polymers and metal-organic frameworks and to explain possible applications of those properties
Chemical composition and biological activity of essential oil from needles of selected plants from mediterranean cypress, phoenicean juniper and aleppo pine : diploma thesis
No full textEteriĉna ulja iz iglica ĉempresa (Cupressus sempervirens L.), gluhaĉa ili primorske somine (Juniperus phoenicea L.) iz porodice ĉempresovki (Cupressaceae) te alepskog bora (Pinus halepensis Miller) iz porodice borovki (Pinaceae) izolirana su metodom vodene destilacije u aparaturi po Clevengeru. Kemijski sastav izoliranih ulja je odreĊen pomoću vezanog sustava plinske kromatografije s masenom spektrometrijom (GC-MS). Najzastupljeniji spoj kod eteriĉnih ulja ĉempresa i gluhaĉa bio je monoterpen α-pinen (32,75 % i 61,34 %), a kod alepskog bora diterpen kaur-16-en (16,77 %). Ispitana je antioksidacijska aktivnost navedenih eteriĉnih ulja kao i sposobnost inhibicije enzima acetilkolinesteraze i butirilkolinesteraze. Ulja nisu pokazala znaĉajnu antioksidacijsku aktivnost, dok su pokazala inhibicijsku aktivnost na acetil- i butirilkolinesterazu. Eteriĉno ulje alepskog bora pokazalo je najveću inhibicijsku aktivnost na acetilkolinesterazu, a eteriĉno ulje ĉempresa na butirilkolinesterazu. Ispitana je i antimikrobna aktivnost metodom mikrodilucije te je utvrĊeno da eteriĉna ulja nemaju znaĉajnu antimikrobnu aktivnost, ali pokazuju jaku antifungalnu aktivnost.Essential oils from needles of Mediterranean cypress (Cupressus sempervirens L., Cupressaceae) and the Phoenicean juniper (Juniperus phoenicea L., Cupressaceae) as well as the Aleppo pine (Pinus halepensis Miller, Pinaceae) were isolated using water distillation in the Clevenger type apparatus. Their chemical composition was determined using gas chromatography-mass spectrometry (GC-MS) system. The results showed that monoterpene α-pinene is the most abundant compound in essential oils of Mediterranean cypress and the Phoenicean juniper (32,75 % i 61,34 %), and diterpene kaur-16-ene in the Aleppo pine essential oil (16,77 %). The antioxidant activity of essential oils was tested as well as their acetyl- and butyrylcholinesterase inhibitory activity. Aleppo pine essential oil showed the highest inhibitory activity on acetylcholinesterase, and Mediterranean cypress essential oil on butyrylcholinesterase. Antimicrobial activity was tested by the microdilution method and it was found that essential oils do not have significant antimicrobial activity but they showed high antifungal activity
Polymorphism and pseudopolymorphism in metal complexes : bachelor thesis
No full textPolimorfija je pojavljivanje iste tvari u više različitih kristalnih oblika koji su kemijski identični, ali im se svojstva znatno razlikuju. Polimorfija je jako značajna pojava danas, i jako je istraživana posebno u farmaceutskoj industriji i kristalnom inženjerstvu, a važna je i u proizvodnji novih materijala jer nudi potencijalno bolja svojstva. Ovaj rad se također bavi i razmatranjem gubitka kontrole nad kristalizacijskim procesom, a što dovodi do nemogućnosti dobivanja polimorfa koji želimo. Obrađeni su primjeri polimorfa kao i pseudopolimorfa metalnih kompleksa, uvjeti njihove sinteze i kristalizacije, usporedba njihovih kristalnih struktura te sličnosti i razlike njihovih kristalnih pakiranja.Polymorphism is the appearance of the same substance in several different crystal forms. These crystal forms are chemically identical, but their properties are significantly different. Polymorphism is a very significant phenomenon today and has been intensively studied, especially in the pharmaceutical industry and crystal engineering. It is very important in the production of new materials because it offers potentially better properties. The loss of control over the crystallization process leads to the inability of obtaining the desired polymorph. The examples of polymorphs as well as pseudopolymorphs of metal complexes are discussed, as well as the conditions of their synthesis and crystallization. A comparison of their crystal structures, including similarities and differences of their crystal packings, was also mentioned
Kosher and Halal standards are a tradition in modern food production : bachelor thesis
No full textDa bi prehrambena industrija mogla funkcionirati neometano u današnje vrijeme, potrebno je da ima određene standarde i norme proizvodnje. Kada se proizvod proizvodi prema određenim standardima on od odgovarajućih agencija može dobiti certifikat. Certifikati kupcima ulijevaju povjerenje i jamče kvalitetu. Jedni od rigoroznijih standarda u proizvodnji hrane uključuje Halal i Košer standarde. Ti standardi su utemeljeni prije mnogo godina, zapisani su u Svetim knjigama i iziskuju pridržavanje brojnih pravila. Prehrambena industrija koja je željna određeni proizvod certificirati kao Halal ili Košer mora ispuniti brojnu dokumentaciju, proći kroz edukaciju i inspekciju i ukoliko su svi ti uvjeti zadovoljeni može dobiti odgovarajući certifikat. Važno je naglasiti da cjelokupna proizvodnja od zaprimanja sirovine pa sve do transporta gotovog proizvoda iziskuje poslovanje isključivo u skladu sa tim standardima. Ukoliko je prekršena i najmanja zabrana proizvod ne može dobiti certifikat. Zbog toga što ovi proizvodi traže specifičniji način proizvodnje, često oni na tržištu imaju i puno veću cijenu. No, osobe kojima ovakva prehrana predstavlja njihovu vjeru i život cijene ove proizvode i spremni su izdvojiti i pozamašne svote novca kako bi nastavili živjeti svoju vjeru.Nowadays, in order for food industry to work unobstructedly, it is crucial for it to have its manufacturing standars and norms. When a product is being manufactured acoording to a certain standards, it can get a certificate from the following agencies. Certificates mean trust and guarantee quality to the potentional buyers. One of the most strict standards in the food industry are Halal and Košer standards. Those are founded many years ago, are written in sacred books and require complying with the certain rules. If the food industry is willing to certificate a certain product as a Halal or Košer product, it has to fill out proper documentation and go through education and inspection. If all the requirements are fulfilled, it can get the corresponding certificate. It must be noted that the whole production, from the acceptance of a raw material to the transport of the finished product, has to be according to those standards. If a single restraining order is violated, the product cannot get the certificate. Because of a specific way of production that is required, the products are often higher priced on the market. Still, if that kind of nutrition represents a belief or a certain lifestyle to some people, they appriciate it and are willing to give a great deal of money to keep living what appears to be their belief.
Overwiew of antimicrobical activity of herbal extracts in meat : bachelor thesis
No full textUnatoč znatnom napretku prehrambene industrije i poboljšanju higijenskih navika, zbog velikog broja infekcija i intoksikacija uzrokovanih patogenim mikroorganizmima, sigurnost hrane predstavlja veliki problem. Da bi hrana bila zdravstveno ispravna i sigurna, postoji potreba za primljenom različitih aditiva čija je upotreba sve upitnija pa stoga primjena prirodnih aditiva u svrhu poboljšanja kvalitete hrane postaje sve češća. Obzirom da je meso pogodan medij za razvoj mikroorganizama vrlo je važno spriječiti rast patogena koji mogu izazvati njegovo kvarenje. Biljke i začini se koriste već dugi niz godina kao aditivi ili u svrhu aromatiziranja namirnica te se smatraju najčešće korištenim prirodnim antimikrobnim sredstvima protiv različitih patogenih mikroorganizama.Despite considerable progress in the food industry and improved hygiene habits, due to the large number of infections and intoxications caused by pathogenic microorganisms, food safety is a major problem. In order to be secure and safe, there is a need for various preservatives with questionable use, so the use of natural additives for improvement of food quality is becoming more common. Meat is a suitable medium for the microorganisms development, it is very important to prevent the growth of pathogens that can cause its spoilage. Herbs and spices have been used for many years as food additives or for food flavoring and they are considered as the most commonly used natural antimicrobial agents against various pathogenic microorganisms