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Glyphosate
No full textGlifosat je aktivna tvar mnogih poznatih herbicidnih sredstava. Nakon prve sinteze glifosata, primarna uloga mu je bila vezanje metala. Otkrićem njegovog herbicidnog djelovanja te uvođenjem genetski modificiranih usjeva, postao je jedan od najpoznatijih i najviše korištenih herbicida na svijetu zbog svojeg specifičnog mehanizma djelovanja. Glifosat sprječava sintezu aromatskih aminokiselina što uzrokuje sušenje biljke. Iz tog razloga, širom svijeta upotrebljava se za kontrolu i suzbijanje neželjenog korova na poljoprivrednim ili nepoljoprivrednim površinama. Posljednjih godina, znanstvenici su pridodali pažnju istraživanjima koja proučavaju utjecaj glifosata na okoliš i živa bića. Njegovo negativno djelovanje na zdravlje ljudi i životinja postaje sve izraženije, stoga se u nekim državama upotreba glifosata postupno počinje ograničavati. Alternativno sredstvo za glifosat još nije pronađeno, ali postoji nekoliko različitih agronomskih tehnika koje smanjuju korištenje glifosata.Glyphosate is the active substance of many known herbicides. After the first synthesis of glyphosate, its primary function was metal binding. Due to its specific mechanism of action, glyphosate became one of the most famous and widely used herbicides after discovery of its herbicidal activity and introduction of genetically modified crops. Glyphosate prevents the synthesis of aromatic amino acids which causes the plant to dry out. For that reason, it is used worldwide for control and repression of unwanted weeds on both agricultural and non-agricultural areas. In the recent years, scientists have paid increased attention to study the effects of glyphosate on environment and living organisms. Some countries are starting to restrict the use of glyphosate due to its negative effects on human and animal health. The alternative to glyphosate has not yet been found, but there are several agronomic techniques which reduce its use
Development of colorimetric analytical techniques for the characterization of milk quality and the ecological approach to cheese production
No full textCilj ovog diplomskog rada je razviti brzu, jednostavnu, ekonomski i ekolobki prihvatljivu metodu koja se može primijeniti u industrijskim uvjetima, brzim pregledima na terenu ili u muznim uređajima, za određivanje kalcija u mlijeku kao primarnom proizvodu u proizvodnji sira. Mlijeko sadrži visoke koncentracije kalcija. Javlja se u dva oblika, slobodnom ionskom obliku i kalciju povezanom s mlije nim proteinima (kazeini), koji se job naziva i koloidni kalcijev fosfat. Odabrani su kolorimetrijska metoda i kolorimetrijski reagens, Arsenazo III koji se koristio u obliku natrijeve soli. Arsenazo III u reakciji sa kalcijem u otopini stvara obojenje od ruži aste do plave boje ovisno o koncentraciji kalcija. Kompleks koji stvara s kalcijem mora biti u prikladnom puferu. Kao kolorimetar se koristio pametni telefon. Kalcij se određivao u uzorcima mlijeka i filtrata mlijeka. Karakterizacija metode za izvedbu kolorimetrije izvedena je pomo u ugrađene kamere. Određeni kolorimetrijski uzorci obrađeni su i na spektrofotometru (Shimadzu UV-1700) kako bi se provjerila valjanost rezultata. Mjerenja boja koja se izvode izravno pomo u kamere pametnog telefona dobivaju se pomo u aplikacije RGB Detector (The programmer), preuzete s Google Play Store-a.The aim of this thesis is to develop a fast, simple, economically and ecologically acceptable method that can be applied in industrial conditions, rapid inspections in the field or in milking machines, for the determination of calcium in milk as a primary product in cheese production. Milk contains high concentrations of calcium. It occurs in two forms, free ionic form and calcium associated with milk proteins (caseins), which is also called colloidal calcium phosphate. A colorimetric method and a colorimetric dye, Arsenazo III, which was used in the form of a sodium salt, were chosen. Arsenazo III in the reaction with calcium in the solution creates a pink to blue color depending on the concentration of calcium. The complex it forms with calcium must be in a suitable buffer. A smartphone was used as a colorimeter. Calcium was determined in samples of milk and milk filtrate. The characterization of the colorimetry method was performed using a built-in camera. Certain colorimetric samples were also processed on a spectrophotometer (Shimadzu UV-1700) in order to check the validity of the results. Color measurements performed directly using the smartphone camera are obtained using the RGB Detector (The programmer) app, downloaded from the Google Play Store
Distribution of carnosine in chicken meat samples
No full textSintezom aminokiseline β-alanina i ʟ-histidina nastaje karnozin, dipeptid mnogobrojnih pozitivnih u inaka na zdravlje ovjeka. Karnozin ima ulogu pH pufera, kelatora metalnih iona, antioksidansa, imunomodulatora i neurotransmitera te se zbog toga najvibe koristi u medicini ali i sportu te kozmetici. Hrana oboga ena biolobkim djelatnim tvarima (nutricinima) ima pozitivan u inak na zdravlje ovjeka pa je određivanje koncentracije nutricina vrlo va~no. Ranija istra~ivanja pokazala su da koncentracija karnozina u mesu ovisi o vrsti mibi nog tkiva pa je koncentracija karnozina u mesu pile ih prsa ve a nego u mesu zabatka za prosje no 40 %. U ovom radu određivana je koncentracija karnozina i anserina u uzorcima mesa pile ih prsa kako bi se vidjelo jesu li dipeptidi ravnomjerno raspoređeni u mesu pile ih prsa. Za određivanje koncentracije koristila se teku inska kromatografija visoke djelotvornosti s UV-VIS detekcijom. Određena je prosje na koncentracija karnozina i iznosila je za lijevi dio prsa (uzorci A) 225,239 mg/kg mesa dok je za desni dio prsa (uzorci B) koncentracija 218,654 mg/kg mesa. Koncentracija anserina za uzorke A iznosila je 852,518 mg/kg mesa a uzorke B 815,616 mg/kg mesa. Dobiveni rezultati pokazali su da nema zna ajne razlike u raspodjeli karnozina i anserina u mesu pile ih prsa s obzirom na dio mesa koji se analizirao.Synthesis of the amino acids β-alanine and ʟ-histidine produces carnosine, a dipeptide with numerous positive effects on human health. Carnosine acts as a pH buffer, metal ion chelator, antioxidant, immunomodulator and neurotransmitter, which is why it is mostly used in medicine, sports and cosmetics. Food enriched with biologically active substances (nutricins) has a positive effect on human health, therefore determining the concentration of nutricins is very important. Earlier research showed that the concentration of carnosine in meat depends on the type of muscle tissue, so the concentration of carnosine in chicken breast meat is higher than in thigh meat by 40% on average. In this work, the concentration of carnosine and anserine in chicken breast meat samples was determined in order to see if the dipeptides are evenly distributed in chicken breast meat. High performance liquid chromatography with UV-VIS detection was used to determine the concentration. The average concentration of carnosine was determined, which for the left part of the breast (A samples) was 225,239 mg/kg of meat, while for the right part of the breast (B samples) the concentration was 218,654 mg/kg of meat. The concentration of anserine for samples A was 852,518 mg/kg of meat, and for samples B 815,616 mg/kg of meat. The obtained results showed that there is no significant difference in the distribution of carnosine and anserine in chicken breast meat,considering the part of the meat that was analyzed
Endocrine disruptors and polycystic ovary syndrome
No full textCilj ovoga rada je istražiti endokrine disruptore, njihovu apsorpciju u organizam i štetne učinke na zdravlje. U tu svrhu, napravljen je literaturni pregled dugogodišnjih istraživanja fokusiranih na endokrine disruptore kojima su ljudi najviše izloženi (bisfenol A, parabeni, triklosan, ftalati i fitoestrogeni). Fokus je stavljen na istraživanja koja su se bavila utjecajem pojedinih endokrinih disruptora na reproduktivni sustav i pokušajem smanjenja nastalih šteta. Naime, endokrini disruptori, kojima su ljudi svakodnevno izloženi i ne mogu se potpuno izbjeći, djeluju već u vrlo malim dozama, a apsorpcijom u organizam ostavljaju brojne posljedice poput hormonalnih poremećaja, pretilosti, raznih poremećaja reproduktivnog sustava (funkcioniranje jajnika, folikulogeneza) itd. U ovom radu, poseban naglasak stavljen je na utjecaj disruptora na nastanak sindroma policističnih jajnika. Iako mehanizam nastanka sindroma nije u potpunosti razjašnjen, utvrđeno je da izloženost endokrinim disruptorima utječe na nastanak inzulinske rezistencije (koja je usko povezana s ovim sindromom), na nakupljanje kolesterola (što dovodi do pretilosti i može sudjelovati u nastanku sindroma), na ekspresiju gena, odvijanje određenih staničnih procesa i sl. Konkretna veza disruptora i ovog sindroma i dalje se detaljno istražuje kako bi se dobila što jasnija slika koja bi mogla pomoći u liječenju sindroma, a moguće i u sprečavanju njegovog nastanka.The aim of this paper is to explore endocrine disruptors, their absorption into the body, and their harmful effects on the health. To this end, a literature review was conducted, focusing on longterm studies of endocrine disruptors to which humans are most exposed (bisphenol A, parabens, triclosan, phthalates, and phytoestrogens). The focus was on studies examining the impact of specific endocrine disruptors on the reproductive system and attempts to mitigate the damage caused. Namely, endocrine disruptors, to which people are exposed daily and cannot completely avoid, have effects even at very low doses, and their absorption into the body leads to numerous consequences, such as hormonal imbalances, obesity, various reproductive system disorders (ovarian function, folliculogenesis), and more. This paper places special emphasis on the impact of disruptors on the development of polycystic ovary syndrome. Although the mechanism of this syndrome is not fully elucidated, it has been established that exposure to endocrine disruptors influences the development of insulin resistance (closely linked to this syndrome), cholesterol accumulation (which leads to obesity and may contribute to the syndrome), gene expression, cellular processes, etc. The connection between disruptors and this syndrome is under research in order to obtain a clearer understanding that could assist in treating of the syndrome, and possibly in preventing its occurrence
Synthesis of novel pyridoxalimine derivatives as possible multitargeted drugs
No full textZelena kemija ili odr~iva kemija je nov na in razmibljanja koji se sve vibe primjenjuje u kemiji u svrhu o uvanja okoliba i ljudskog zdravlja. Dvanaest principa zelene kemije donijeli su P. Anastas i J. Warner 1998. godine. Mehanokemijska sinteza je metoda zelene sinteze u kojoj se primjenjuje mehani ka sila koju uzrokuju razli ita tijela za mijebanje. Sinteza potpomognuta teku inom (LAG metoda) je vrsta mehanokemijske sinteze u koju se dodaje mala koli ina teku ine, njezina je uloga da pripomogne sintezi i nema ulogu otapala. Vitamin B6 je vitamin koji u svojoj strukturi ima razli ite funkcionalne skupine koje mu omogu uju razli ite kemijske modifikacije. Kvaterne amonijeve soli su organski spojevi gdje su na dubik vezane 4 razli ite skupine. Cilj ovog rada je sinteza kvaternih soli N-acilhidrazonskih derivata vitamina B6 tj. piridoksal hidroklorida. Sinteza novosintetiziranih spojeva se odvijala u vibracijskom mlinu tijekom 4 sata pomo u sinteze potpomognute teku icom. Sintetizirane su dvije serije kvaternih soli sa razli itim polaznim reaktantima koji su reagirali sa supstituiranim fenacil-bromidima. Struktura novosintetizranih produkata je određena pomo u masene spektroskopije.Green chemistry or sustainable chemistry is a new way of thinking that is increasingly applied in chemistry for the purpose of preserving the environment and human health. The twelve principles of green chemistry were adopted by P. Anastas and J. Warner in 1998. Mechanochemical synthesis is a method of green synthesis in which the mechanical force caused by various mixing bodies is applied. Liquid-assisted synthesis (LAG method) is a type of mechanochemical synthesis in which a small amount of liquid is added, its role is to assist the synthesis and it has no role as a solvent. Vitamin B6 is a vitamin that has different functional groups in its structure that allow it to undergo different chemical modifications. Quaternary ammonium salts are organic compounds where 4 different groups are attached to nitrogen. The aim of this work is the synthesis of quaternary salts of N-acylhydrazone derivatives of vitamin B6, i.e. pyridoxal hydrochloride. The synthesis of the newly synthesized compounds took place in a vibrating mill for 4 hours using liquid-assisted synthesis. Two series of quaternary salts were synthesized with different starting reactants that reacted with substituted phenacyl bromides. The structure of the newly synthesized products was determined using mass spectroscopy
The effect of antioxidants on calcium carbonate precipitation
No full textU radu je istraženo djelovanje antioksidansa protokatehuinske kiseline, PCA (engl. protocatechuic acid), na spontano taloženje kalcijeva karbonata u sustavu poetnih vrijednosti: koncentracija kalcija i karbonata 2,5 mmol dm-3, temperatura 25 °C i pH = 10,419. Proces taloženja praen je potenciometrijski, a dobiveni talozi su karakterizirani svjetlosnom mikroskopijom, infracrvenom spektroskopijom te rendgenskom difrakcijom. Dodatak PCA u taložni sustav kalcijeva karbonata uzrokovao je: inhibiciju spontanog taloženja kalcijeva karbonata, promjenu morfologije istaloženog kalcita te promjenu sastava taloga pri emu se maseni udio kalcita u talogu poveavao s poveanjem koncentracije dodane PCA.The effect of the antioxidant protocatechuic acid (PCA) on the spontaneous precipitation of calcium carbonate was investigated in the system with initial values: concentration of calcium and carbonate ions 5 mmol dm-3, temperature 25 °C and pH 10.419. The progress of the precipitation process was followed potentiometrically and the precipitates were characterized by light microscopy, infrared spectroscopy and x-ray diffraction. The addition of PCA to the calcium carbonate precipitation system caused: inhibition of the spontaneous precipitation of calcium carbonate, a change in the morphology of the precipitated calcite, and an alteration in the composition of the precipitate. Specifically, the mass fraction of calcite in the precipitate increased with the increase of concentration of added PCA
The role of lectins in the immune response
No full textLektini su proteini koji se vežu za ugljikohidrate i glikokonjugate. Zbog sposobnosti prepoznavanja drugih molekula izrazito su važni u raznim biomedicinskim istraživanjima, a primjenu nalaze i u terapiji i dijagnostici. U kontekstu imunosnog odgovora, lektini imaju važnu ulogu kao imunomodulatori. U uro enom imunosnom odgovoru, lektini su uklju eni u aktivaciju sustava komplemenata, prepoznavanje patogena i fagocitozu. Tako er, lektini sudjeluju i u modulaciji ste enog imunosnog odgovora kroz aktivaciju T- i B-stanica. Uz svoju ulogu u zabtiti organizma lektini su povezani s razvojem autoimunih bolesti. U radu su prikazani rezultati iz literaturno dostupnih podataka, a pretraživana je literatura na hrvatskom i engleskom jeziku.Lectins are proteins that bind to carbohydrates and glycoconjugates. Due to their ability to recognize other molecules, they are extremely important in various biomedical research, and they are also used in therapy and diagnostics. In the context of the immune response, lectins play an important role as immunomodulators. In the innate immune response, lectins are involved in complement system activation, pathogen recognition and phagocytosis. Also, lectins participate in the modulation of the acquired immune response through the activation of T- and B-cells. In addition to their role in protecting the body, lectins are associated with the development of autoimmune diseases. The paper presents the results from the data available in the literature, and the literature in Croatian and English was searched
Analysis of the antimicrobial effect of garlic extract on microorganisms from waters of different origin
No full textAntimikrobna svojstva raznih prirodnih spojeva postaju zna ajno podru je istraživanja, ponajvibe zbog sve ve e rezistencije mikroorganizama na antibiotike koji su do sada bili u birokoj uporabi. ebnjak (Allium sativum) vrlo je cijenjen u kulinarstvu, no njegova ljekovita svojstva poznata su od davnina. Sadrži niz biolobki aktivnih spojeva, uklju uju i mnoge s antimikrobnim svojstvima. U ovom radu istražen je antimikrobni u inak razli itih ekstrakata doma eg i kupovnog/uvoznog ebnjaka (podrijetlom iz Kine) na patogene mikroorganizme prisutne u prirodnim vodama. Ekstrakti ebnjaka pripravljeni su u acetonu, etanolu, metanolu i ultra istoj vodi. Ekstrakt doma eg ebnjaka u acetonu pokazao je najbolje antimikrobno djelovanje i to na bakteriji Listerii monocytogenes. Na Gram(+)-bakterijama uo eno je izraženije antimikrobno djelovanje u odnosu na Gram(-)-bakterije. Bakterija Pseudomonas aeruginosa pokazala je najve u otpornost na ispitivane ekstrakte. Pomo u GCMS u gotovo svim su ekstraktima detektirani spojevi: dialil-sulfid, dialil-disulfid, metil-disulfid, dimetil-trisulfid, metil-alil-disuflid te sumporThe antimicrobial properties of various natural compounds are becoming a significant area of research, mostly due to the growing resistance of microorganisms to antibiotics that have been widely used so far. Garlic (Allium sativum) is highly valued in cooking, however, its medicinal properties have been known since ancient times. It contains a number of biologically active compounds, including many with antimicrobial properties. In this paper, the antimicrobial effect of different extracts of home-grown and purchased/imported garlic (originating from China) on pathogenic microorganisms present in natural waters was investigated. Garlic extracts are prepared in acetone, ethanol, methanol and ultrapure water.The extract of home-grown garlic in acetone showed the best antimicrobial activity against Listeria monocytogenes. A more pronounced antimicrobial effect was observed on Gram(+)-bacteria compared to Gram(-)-bacteria. The bacterium Pseudomonas aeruginosa showed the highest resistance to the examined extracts. Using GC-MS, the following compounds were detected in almost all extracts: diallyl-sulfide, diallyl-disulfide, methyl-disulfide, dimethyl-trisulfide, methyl-allyl-disulfid and sulfur
Transition metals complexes of kojic acid: preparation and biological activity
No full textKojinska kiselina (5-hidroksi-2-hidroksimetil-4-piron, C6H6O4) je organska kiselina koja je dobro topljiva u vodi, etanolu i acetonu. Jedan je od nusprodukata u procesu fermentacije riže za slad koji se koristi u proizvodnji sakea, japanskog rižinog vina. Inhibitor je rasta bakterija, gljivica te spriječava razmnožavanje virusa. Zbog mogućnosti modifikacije strukture, što za posljedicu ima brojne strukturne transformacije, danas je poznat velik broj derivata kojinske kiseline, kao i kompleksa prijelaznih metala u kojima se ona koristi kao ligand. Spomenute se skupine spojeva intenzivno proučavaju zbog svoje potencijalne biološke aktivnosti. U ovom radu predstavljeni su značajni rezultati iz literaturno dostupnih podataka koji pokazuju raznovrsnost priprave kompleksa kojinske kiseline, zastupljenost esencijalnih metalnih iona u takvim spojevima, kao i njihovu biološku evaluaciju. U prvom dijelu rada opisane su strukturne značajke kojinske kiseline, najčešće metode priprave kompleksa s kojinskom kiselinom i testovi citotoksičnosti, nakon čega slijedi pregled novijih rezultata vezanih uz protutumorsku, antibakterijsku i antifungalnu aktivnost kompleksa prijelaznih metala s kojinskom kiselinom.Kojic acid (5-hydroxy-2-hydroxymethyl-4-pyrone, C6H6O4) is an organic acid that is highly soluble in water, ethanol and acetone. This acid is a by-product of the fermentation process of malted rice, which is used for the production of sake, a Japanese rice wine. It is an inhibitor for the growth of bacteria and fungi and prevents the multiplication of viruses. Today, a large number of kojic acid derivatives and transition metal complexes are known because they can change their structure, leading to structural transformations. These compounds are intensively studied due to their potential biological activity. In this paper, important results from the literature are presented, showing the diversity of preparation of kojic acid complexes, the presence of essential metal ions in such compounds and their biological evaluation. The first part of the article describes the structural characteristics of kojic acid, the most common methods for the preparation of complexes with kojic acid and cytotoxicity tests, followed by an overview of recent results on the antitumor, antibacterial and antifungal activity of complexes of transition metals with kojic acid
Preparation and structural characterization of naphthalanhydride derivatives
No full textU ovome zavrbnom radu opisana je priprava 5,6-diamino-1H,3Hbenzo[de]izokromen-1,3-diona, derivata naftalanhidrida, spoja 3. Ciljni produkt, spoj 3, e se koristiti kao polazni spoj za reakciju s alifatskim i aromatskim aminima s ciljem priprave odgovaraju eg imidnog derivata. Pripravljeni imidni derivat e se u nastavku ovoga istraživanja koristiti kao indikator za određivanje koncentracije selenija. Za pripravu spoja 3, predložen je sintetski put koji se sastoji od tri reakcijska koraka. U prvom koraku predloženog sintetskog puta, polazni spoj 6-brom-1H,3H-benzo[de]izokromen-1,3-dion podvrgnut je reakciji elektrofilne aromatske supstitucije pri emu je uspjebno pripravljen nitro derivat, spoj 1. Drugi korak predloženog sintetskog puta podrazumijeva nukleofilnu aromatsku supstituciju spoja 1, bto rezultira uvođenjem azidne skupine u naftalanhidridnu strukturu, odnosno pripravom spoja 2. Spoj 2 u svojoj strukturi posjeduje azidnu i nitro skupinu koje su uspjebno reducirane u amino skupinu reakcijom kataliti kog hidrogeniranja, a takva reakcija rezultirala je uspjebnom pripravom spoja 3. Strukture pripravljenih spojeva pretpostavljene su 1H i 13CNMR spektroskopijom.In this thesis preparation of 5,6-diamino-1H,3H-benzo[de]isochromene-1,3-dione, napthalic anhydride derivative, compound 3 is described. Compound 3 will be used as a starting compound for the reaction with aliphatic and aromatic amines with the aim of preparation of the corresponding imide derivative. The prepared imide derivative will be used in the continuation of this research as an indicator for determination of selenium concentration. A synthetic route consisting of three reaction steps was proposed. In the first step of the proposed synthetic route, the starting compound 6-bromo-1H,3H-benzo[de]isochromene-1,3-dione was subjected to an electrophilic aromatic substitution reaction, during which the nitro derivative, compound 1, was successfully prepared. The second step of the proposed synthetic route implied the nucleophilic aromatic substitution of compound 1, which resulted in the introduction of an azide group into the naphthalene anhydride structure, respectively preparation of compound 2. Compound 2 possess an azide and nitro group in its structure which were successfully reduced to a vicinal amino groups by a catalytic hydrogenation reaction. This reaction resulted in formation of compound 3. The structures of the prepared compounds were assumed by 1H and 13CNMR spectroscopy