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Fundamentals of proteomics
No full textProteomika je brza i efikasna znanstvena disciplina primarno orijentirana na izučavanje proteoma ili sume proteina, tkiva, stanica i staničnih fluida. Izučavanjem ovih komponenti, dolazi se do širokog spektra podataka o ekspresiji i modifikaciji određenih željenih proteina. Proteini su sastavni infrastrukturni i funkcionalni dijelovi stanica koji su građeni od raznolikog poretka aminokiselina po uzorcima na kalupe DNA i RNA. Proteomika je bazirana na opsežnom polju istraživanja proteina u koje spadaju strukturalne i fiziološke značajke proteina, tj. uloge proteina u organizmima. Ponajveći broj otkrića u području proteomike pronalazi upotrebu u medicinskim svrhama, ponajviše lječenju protiv karcinoma kao i u efektivnom i ciljnom djelovanju lijekova na određene stanične mehanizme koje su uzrok raznih upala i bolesti organizama. Uz proteomiku bitan je i pojam proteoma koji označava sveobuhvatni skup proteina koje producira organizam. U uži kontekst proteoma ulaze i prepravke te promjene koje se mogu zbiti na osnovnom, nativnom proteinu ukoliko se organizam izloži dugotrajnom i raznolikom broju faktora koji će utjecati na promjenu funkcionalnosti i strukture proteina.Proteomics is a fast and efficient scientific discipline primarily focused on the study of proteomes or the sum of proteins, tissues, cells and cellular fluids. By studying these components, a wide range of data is obtained based on the expression and modification of certain desired proteins. Proteins are integral infrastructural and functional parts of cells that are built from a diverse order of amino acids by patterns on DNA and RNA molds. Most of the discoveries in the field of proteomics are used for medical purposes, especially in the actions against cancer as well as in the effective and targeted action of drugs on certain cellular mechanisms that cause various inflammations and diseases of organisms. In addition to proteomics, the notion of genome is closely related. Within proteomics important term is also a proteome which denotes a comprehensive set of proteins produced by an organism. The narrower context of the proteome also includes modifications and changes that can occur in the basic, native protein if the organism is exposed to a long-lasting and diverse number of factors that will affect the change in the functionality and structure of the protein
The influence of sulfur centered radicals on processes in model lipid systems
No full textLipidna peroksidacija i geometrijska izomerizacija su biološki važni procesi koji mogu imati štetan utjecaj na organizme. Cilj ovog rada bio je ispitati produkte lipidne peroksidacije i cis, trans−izomerizacije u modelnom sustavu micela, priređenom iz linolne kiseline (LH) i tenzida, uz inicijaciju γ−zračenjem u različitim eksperimentalnim uvjetima. U radu je korišten Na2S kao prekursor za generiranje H2S odnosno HS− u modelnim sustavima LH. Ispitani su utjecaj pH, brzina doze zračenja, koncentracija Na2S u uvjetima ravnoteže sa zrakom te u anaerobnim uvjetima. Pokazano je da hidroperoksidi i trans−izomeri LH nastaju i u oksidacijskim uvjetima. U anaerobnim uvjetima izomerizacija je predominantan proces pri čemu uz nestajanje cis−konfiguracije dvostruke veze, istovremeno nastaju i dva mono trans− i di trans−izomera. Izmjeren je hidrodinamički promjer micela koji se smanjuje s porastom pH, a zeta potencijal ima sve negativniji naboj.Lipid peroxidation and cis, trans−isomerization are biologically important processes that can have deleterious effects on organisms. The aim of this study was to investigate the products of lipid peroxidation and cis, trans−isomerization in a model system of micelles prepared from linoleic acid (LH) and surfactant, induced by gamma radiation under different experimental conditions. Na2S was used as a precursor for the generation of H2S/HS− in the model LH system. The influence of pH, radiation dose rate, Na2S concentration under air equilibrium conditions and under anaerobic conditions were investigated. It has been shown that under oxidative conditions hydroperoxides and trans−isomers of LH are also formed. Under anaerobic conditions, isomerization is the predominant process with the disappearance of the cis−configuration of the double bond and the simultaneous formation of two mono trans and di trans−isomers. It has been measured that the hydrodynamic diameter of the micelle decreases with increasing pH and the zeta potential becomes increasingly negatively charged
Determination of quality and safety of dietary supplements using separation techniques
No full textDodaci prehrani izvor su hranjivih tvari poput vitamina, minerala i biljnih ekstrakata, te se koriste kao nadopuna prehrani ako se hranjive tvari nedovoljno unose putem hrane. Posljednjih godina trend proizvodnje i konzumacije dodataka prehrani raste te danas postoji širok asortiman proizvoda. Mnogi proizvodi osim obogaćivanja prehrane hranjivim tvarima navode i djelotvorne učinke poput smanjenja apetita, povećanja mišićne mase i slično. Da bi se postigli djelotvorni učinci osim dozvoljenih sastojaka dodacima prehrani dodaju se sintetski proizvedene tvari i farmaceutici koji su inače sastavni dio lijekova, to dovodi u pitanje kvalitetu i sigurnost dodataka prehrani, a time i potrebu za razvijanjem novih analitičkih metoda analize. U ovom radu opisane su i objašnjene separacijske metode koje se koriste za analizu dodataka prehrani. Opisani su principi analiza i primjena metoda kod analiza dodataka prehrani.Dietary supplements are a source of nutrients such as vitamins, minerals and plant extracts. They are used as a supplement in diet if nutrients are insufficiently ingested through the food. Dietary supplement production and use has increased over recent years, therefore today there is a wide range of products. Many products, in addition to enriching the diet with nutrients, also have a positive effect on reducing appetite, building muscle mass, etc. In addition to the permitted ingredients, components of medications such as synthetic substances and pharmaceuticals, are added to food supplements, this calls into question the quality and safety of dietary supplements, and hence the need for analytical methods of analysis. This thesis describes and explains the separation methods used for the analysis of dietary supplements as well as the principles of analysis and application of methods in the analysis of dietary supplements
Determination of food quality
No full textOdređivanje kvalitete hrane je vrlo važan postupak pri kojemu se upotrebljavaju razne analitičke metode u svrhu prikupljana podataka o udjelima pojedinih elemenata u hrani, njezinoj sigurnosti, hranjivoj vrijednosti te ispitivanja organoleptičkih svojstava. Najčešće upotrebljavane metode kemijske analize hrane su kromatografske, spektrofotometrijske, volumetrijske, gravimetrijske, taložne i destilacijske metode. Cilj ovog rada bio je istražiti i opisati metode koje se upotrebljavaju prilikom analize hrane te otkriti zašto se hrana uopće mora provjeravati, što su to organoleptička svojstva te analizira li se hrana samo pomoću instrumenata ili i na druge načine, također razjasniti što se sve nalazi u hrani i kako određene komponente djeluju na hranu te kakav je utjecaj mikroorganizama. Osim prethodno navedenog, spomenute su i zakonske regulacije vezane za dodatke hrani te potrebe tržišta vezane za hranu koja se prodaje u trgovinama.Determination of food quality is a very important procedure in which various analytical methods are used for the purpose of collecting data on the proportions of individual elements in food, its safety, nutritional value and testing of organoleptic properties. The most commonly used methods of chemical analysis of food are chromatographic, spectrophotometric, volumetric, gravimetric, precipitation and distillation methods. The aim of this paper was to explore and describe the methods used in food analysis and to find out why food must be checked at all, what are the organoleptic properties and whether food is analyzed only with instruments or in other ways, also to clarify what kind of compounds can be found in food and how certain components affect food, also the impact of microorganisms. In addition to the above, in the paper is also mentioned the topic of legal regulations related to food additives and the needs of the market related to food that is sold in supermarkets
Antioxidant potential of selected phenolic acids - a theoretical approach
No full textU zadnjih nekoliko desetljeća antioksidansi su postali čest predmet znanstvenih istraživanja zbog njihove uloge u oksidativnom stresu i etiologiji mnogih bolesti. U ove se spojeve ubraja širok spektar prirodnih mono- i polifenolnih spojeva, primjerice fenolne kiseline, ali i značajan broj sintetskih polifenolnih spojeva. U ovom radu dan je pregled teoretskih istraživanja antioksidacijskog potencijala odabranih fenolnih kiselina. U okviru rada razmatrani su odgovarajući termodinamički parametri ključni za pojedini mehanizam antioksidacijske aktivnosti, na temelju kojih se može izvući zaključak o njihovom antioksidacijskom potencijalu. Osim toga, u radu su prikazani rezultati ispitivanja reakcije fenolnih kiselina s odabranim slobodnim radikalima a ispitani mehanizmi bili su HAT, SET-PT, SPLET i RAF, pri čemu su ispitivanja provedena u nepolarnom i polarnom mediju. Na osnovu izračunatih parametara, određeno je koji su mehanizmi mogući i međusobno kompetitivni te koja od ispitivanih fenolnih kiselina ima veći antiokisidacijski potencijal.In the last several decades, antioxidants have become frequent subject of scientific investigations due to their role in oxidative stress and aetiology of various diseases. Antioxidants include a broad spectrum of mono- and polyphenolic compounds, such as phenolic acids, and also a significant number of synthetic polyphenolic compounds. In this thesis, an overview of theoretical research on antioxidant potential of selected phenolic acids was given. Adequate thermodynamic parameters which play the key role in selected mechanisms of antioxidant activity were also studied and a conclusion regarding antioxidant potential was drawn from this study. Additionally, results of studies of reactions of phenolic acids with free radicals were presented, and studied mechanisms were HAT, SET-PT, SPLET and RAF, in polar and non-polar medium. Based on the results of computed parameters, possible and competitive mechanisms were determined, as well as phenolic acids with higher antioxidant potential
Macrocyclic compounds design for selective complexation of metal ions
No full textMakrociklički spojevi su cikličke makromolekule ili ciklički dio makromolekule koji se sastoji od najmanje devet atoma u prstenu od kojih su najmanje tri donorna atoma. U ovom radu proučavani su makrocikli kao takvi, njihove konformacije (endo / egzo), makrociklički efekt i konstanta stabilnosti, podjela prema obliku i funkcionalnim skupinama te prema vrsti i broju donorskih atoma. Također je opisano kompleksiranje metalnih iona i kompleks domaćin-gost. Kao metoda izdvajanja metalnih iona opisana je ekstrakcija koja ima mogućnost detekcije metala u vrlo niskim koncentracijama. Ujedno, navedena su "pravila" i činjenice o kojima je potrebno voditi računa prilikom dizajniranja makrocikličkih liganda za ekstrakciju metalnih iona.Macrocyclic compounds are cyclic macromolecules or a cyclic part of macromolecule consisting of at least nine ring atoms of which at least three are donor atoms. In this paper, macrocycles as such, their conformations (endo / exo), macrocyclic effect and stability constant, classification according to shape, functional groups, types and number of donor atoms were studied. Metal ion complexation and host-guest complex are also described. As a method of extracting metal ions, extraction which can detect metals in a very low concentrations has been described. At the same time, the "rules" and facts that need to be taken into account when designing macrocyclic ligands for metal ion extraction are stated
Vitamin C as antioxidant and prooxidant
No full textL-askorbinska kiselina, poznata pod imenom vitamin C, jedan je od najproučavanijih vitamina današnjice zbog izrazito povoljnih učinaka na organizam. Ljudski organizam ne može sintetizirati vitamin C te ga je stoga potrebno svakodnevno unositi hranom putem raznovrsnog voća i povrća. Svakodnevni unos vitamina C u određenoj dozi, ali i intravenozna primjena, predmet je brojnih in vitro i in vivo istraživanja. Takva istraživanja provode se s ciljem utvrđivanja antioksidacijskog i prooksidacijskog učinka ovog vitamina na ljudski organizam. Naime, kao antioksidans, vitamin C neutralizira slobodne radikale na način da im donira vodik i stabilizira ih. Slobodni radikali uzrokuju mnoge bolesti, a upravo vitamin C omogućuje borbu protiv istih. Osim kao antioksidans, u određenim uvjetima djeluje i kao prooksidans jer proizvodi vodikov peroksid koji je citotoksičan. To njegovo svojstvo se koristi u liječenju raka zbog toga jer vodikov peroksid ubija stanice raka bez da čini štetu zdravim stanicama organizma.L-ascorbic acid, known as vitamin C, is one of the most studied vitamins today due to its extremely beneficial effects on the body. The human body cannot synthesize vitamin C and therefore it is necessary to take it daily through food through a variety of fruits and vegetables. Daily intake of vitamin C in a certain dose, but also intravenous administration, is the subject of numerous in vitro and in vivo studies. Such research is conducted with the aim of determining the antioxidant and prooxidative effect of this vitamin on the human body. Namely, as an antioxidant, vitamin C neutralizes free radicals by donating hydrogen and stabilizing them. Free radicals cause many dangerous diseases, and vitamin C helps to fight them. Apart from being an antioxidant, under certain conditions it also acts as a prooxidant because it produces hydrogen peroxide which is cytotoxic. This property is used in the treatment of cancer because hydrogen peroxide kills cancer cells without doing damage to healthy cells of the body
Determination of lutein content in laying hens feed
No full textLutein je antioksidans koji je bitan za ljudsko zdravlje te ga je potrebno unositi u organizam. Nalazimo ga u jajima, a količina luteina u jajima ovisi o količini luteina u hrani za nesilice. Ispitivana je najpovoljnija metoda priprema uzoraka koja uključuje ekstrakciju potpomognutu ultrazvukom korištenjem ultrazvučne sonde (UZVS) u trajanju od 3 min, bez zagrijavanja i pri t = 0. Pripremljeni uzorci analizirani su HPLC metodom. Uspoređena je koncentracija luteina u šest različitih smjesa hrane za nesilice koje su različitog sastava. Najveću koncentraciju luteina imala je hrana za nesilice obogaćena luteinom i drugim nutricinima a iznosila je 14,877 mg/kg hrane. Hrana za nesilice obogaćena luteinom i drugim nutricinima, ali pripremljena godinu dana ranije imala je znatno manju koncentraciju luteina koja je iznosila 3,752 mg/kg hrane. Vrlo visoku koncentraciju luteina imala je hrana za nesilice obogaćena samo luteinom te je iznosila 13,929 mg/kg hrane. Najnižu koncentraciju imala je hrana za nesilice obogaćena vitaminom E s iznosom od 0,321 mg/kg hrane.Lutein is an antioxidant that is important for human health and needs to be taken into the body. We find it in eggs but the amount of lutein in eggs depends on the amount of lutein in laying hens feed. The best method of sample preparation has been researched, and it includes ultrasonic assisted extraction using an ultrasonic probe (UZVS) for 3 min, without heating and at t = 0. The prepared samples were analyzed by HPLC method. We compared concentraction od lutein in six different mixtures of laying hens feed with different composition. The highest concentration of lutein was in laying hens feed enriched with lutein and other nutrients and amounted to 14.877 mg / kg of food. Laying hens food that were enriched with lutein and other nutrients, but prepared a year earlier had a significantly lower concentration of lutein, which was 3.752 mg / kg of food. Laying hens food that is enriched only with lutein had a very high concentration of lutein and amounted to 13.929 mg / kg of food. The lowest concentration was found in laying hens food enriched with vitamin E in the amount of 0.321 mg / kg of food
Production of carbon electrodes made by carbonization of polyethylenterephthalat waste and its usage in lithium batteries
No full textFizikalna,kemijskaimehaničkasvojstvasintetičkihpolimera,zajednosrelativnoniskim troškovima proizvodnje,učinilisuplastičnepolimernematerijaleidealnimmaterijalimaza masovnuproizvodnju.Nekontroliranapotrošnjaplastičnihmaterijalarezultiralajejednim od najvećihproblemazagađivanjaokoliša,stogajerazvojtehnologijazazbrinjavanje plastičnogotpadaodizuzetnevažnosti.Trećikorakrecikliranjaplastičnihmaterijalaje njihova kemijskapretvorbaunoveproizvode.Kaotemaovogradaizabranajekemijska pretvorbapolietilentereftalata(PET)pirolizomialternativnaupotrebaprodukatapirolizeu proizvodnjielektrodazakemijskespremnikeelektričneenergije.PirolizaPET-aje izvršenanasrednjojtemperaturiod650°Cuinertnojatmosferi.Glavniproduktpirolizeje tereftalnakiselinaštojerezultattermičkedepolimerizacije.Drugiproduktjeamorfniugljik koji jekorištenzapripravukatodeLiCoO2 zakonstrukcijulitijevogakumulatora. Proizvodipirolizekarakteriziranisutehnikamarendgenskedifrakcijeiinfracrvene spektroskopije.Konstruiranilitijevakumulatorkarakteriziranjeelektrokemijskim metodamacikličkevoltametrije(CV)ielektrokemijskeimpedancijskespektroskopije (EIS).Thephysical,chemicalandmechanicalpropertiesofsyntheticpolymers,togetherwiththe relativelylowproductioncosts,havemadeplasticpolymericmaterialsidealmaterialsfor massproduction.Uncontrolledconsumptionofplasticmaterialshasresultedinoneofthe biggestproblemsofenvironmentalpollutionthereforethedevelopmentoftechnologiesfor plasticwastedisposalisofutmostimportance.Thethirdstepinrecyclingplasticmaterials is theirchemicalconversionintonewproducts.Thetopicofthispaperisthechemical conversionofpolyethyleneterphthalate(PET)bypyrolysisandthealternativeuseof pyrolysis productsintheproductionofelectrodesforbatteriesaschemicalenergystorage devices.PyrolysisofPETwasperformedatamediumtemperatureof650°Cinaninert atmosphere.Themainproductofpyrolysisisterephthalicacidwhichistheresultof thermaldepolymerization.Thesecondproductisamorphouscarbonwhichwasusedto preparetheLiCoO2cathodefortheconstructionofalithiumbattery.Pyrolysisproducts arecharacterizedbyX-raydiffractionandinfraredspectroscopytechniques.The constructedlithiumbatteryischaracterizedbyelectrochemicalmethodsofcyclic voltammetry(CV)andelectrochemicalimpedancespectroscopy(EIS)
Influence of gallic acid on calcium oxalate precipitation
No full textPotraga za učinkovitim lijekom ili inhibitorom u procesu stvaranja bubrežnih kamenaca ima bila obećavajuća tema za istraživanje smanjenja rizika od nastanka bolesti. Međutim, suočeno je s nekoliko izazova u istraživanju najčešćih sastojaka bubrežnih kamenaca, kalcijev oksalat i njegovi hidratni oblici (COM, COD i COT). Ova studija usmjerena je na pripremu i strukturna karakterizacija (TG, XRD, FTIR, SEM) hidrata kalcijevog oksalata u prisutnosti galne kiseline (GA) i mijenjanjem radnih parametara kao što su temperatura (25 C, 36,5 C i 48 C), pH (5,6, 6,5 i 7,5) i količinu dodanog GA (u rasponu od 100 mg do 1000 mg). Odgovor površinska metodologija primijenjena je kako bi se ocijenili učinci radnih parametara u formiranje COM i COD, te za optimizaciju procesa prema maksimiziranju njihovog sadržaja uzorci. Rezultati su pokazali da GA inhibira stvaranje COM (0-100%) i pospješuje formiranje KPK (0 99%), dok su srednji pH i količina dodanog GA pokazale značajan učinak u procesu nastanka KPK. Kako bi se istražile interakcije uspostavljene u proces stvaranja i moguća adsorpcija između GA i formiranih kristala, elektrokemijski izvršena su mjerenja.The search for an efficient drug or inhibitor in the formation process of kidney stones has been a promising research topic towards reducing the risks of the formation of disease. However, several challenges have been faced in investigating the most common constituents of kidney stones, calcium oxalate and its hydrate forms (COM, COD and COT). This study focuses on the preparation and structural characterization (TG, XRD, FTIR, SEM) of calcium oxalate hydrates in the presence of gallic acid (GA) and by varying operating parameters such as temperature (25 C, 36.5 C and 48 C), pH (5.6, 6.5 and 7.5) and amount of added GA (ranging from 100 mg to 1000 mg). Response surface methodology was applied in order to evaluate the effects of operating parameters in the formation of COM and COD, and for the process optimization towards maximizing their content in samples. The results indicated that GA inhibited the formation of COM (0-100%) and promoted the formation of COD (0 99%), while a medium pH and the amount of added GA showed a significant effect in the process of COD formation. In order to investigate the interactions established in the formation process and the possible adsorption between GA and the formed crystals, electrochemical measurements were performed