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A review of chemical composition, pharmacology, toxicology and application of selected species of chamomile
No full textKamilica (Matricaria chamomilla L.) je najpoznatija jednogodišnja ljekovita biljka
iz porodice Asteraceae. Podrijetlom je iz Europe, a sada je rasprostranjena po cijelom svijetu. Koristi se već tisućama godina te zbog toga ima široku primjenu u tradicionalnoj medicini i izvan nje. Kao i ostale biljne vrste, kamilica sadrži brojne kemijske komponente koji igraju glavnu ulogu u određivanju njezinih bioaktivnih svojstava. To uključuje organske kiseline, flavonoide, kumarine, terpenoide te druge spojeve koji posjeduju protuupalna, antioksidacijska, antialergijska, antimikrobna, analgetska, antikancerogena i hepatoprotektivna svojstva. Kako bi se bolje i detaljnije istražila farmakokinetika i toksičnost ove biljke, potrebno je provesti daljna istraživanja.Chamomile (Matricaria chamomilla L.) is the most famous annual medicinal plant from the Asteraceae family. It is native to Europe and is now widespread throughout the world. It has been used for thousands of years and is therefore widely used in traditional medicine and beyond. Like other plant species, chamomile contains numerous chemical components that play a major role in determining its bioactive properties. These include organic acids, flavonoids, coumarins, terpenoids and other compounds that possess anti-inflammatory, antioxidant, antiallergic, antimicrobial, analgesic, anticarcinogenic and hepatoprotective properties. In order to better and more thoroughly investigate the pharmacokinetics and toxicity of this plant, further research is needed
Silver complex synthesis with macrocycles ligands
No full textU ovom istraživanju korišteni su makrociklički ligandi tipa Schiffove baze (mDo5 =
1,5-diaza-2,4:7,8:16,17- tribenzo-9,15-dioksaa-ciklooctadeka-1,5-dien, mDo6 = 1,5-diaza2,4:7,8:17,18-tribenzo-9,16-dioksa-ciklononadeka-1,5-dien i mDo7 = 1,5-diaza-2,4:7,8:18,19- tribenzo-9,17-dioksa-cikloeikoza-1,5-dien). Dobiveni ligandi iskorišteni su za pripravu kompleksa sa srebrovom soli AgOSO₂CF₃. Reakcije su provođene u metanolu i diklormetanu, a kristalizacija je ispitivana metodama difuzije u U-cijevima i pasivnog isparavanja. Kao analitička metoda u ovom radu korištena je FT-IR spektroskopija za karakterizaciju dobivenih spojeva. Dobiveni rezultati u skladu su s literaturnim podatcima i predstavljaju dobru osnovu za buduća detaljnija strukturna istraživanja.In this study, macrocyclic Schiff-base ligands mDO5, mDO6, and mDO7 (mDo5 = 1,5-diaza-2,4:7,8:16,17- tribenzo-9,15-dioxa-cyclooctadeca-1,5-dien, mDo6 = 1,5-diaza2,4:7,8:17,18-tribenzo-9,16-dioxa cyclononadeca-1,5-dien i mDo7 = 1,5-diaza-2,4:7,8:18,19- tribenzo-9,17-dioxa-cycloeicosa-1,5-dien) were used for the preparation of silver(I) complexes with AgOSO₂CF₃. The reactions were carried out in methanol and dichloromethane, and crystallization was done using U-tube diffusion and passive evaporation methods. In this study, FT-IR spectroscopy was used as an analytical method for the characterization of the obtained crystals. The results are consistent with literature data and provide a solid foundation for future, more detailed structural investigations
Preparation of conjugate of mannose and desmuramyl peptide lysine derivative
No full textImunomodulatori temeljeni na muramil-dipeptidu (MDP) i njegovim derivatima
predstavljaju biološki važnu skupinu spojeva u razvoju modernih cjepiva i imunoterapije. Među njima, desmuramil-peptidi privukli su pažnju zbog poboljšane stabilnosti i ciljane biološke aktivnosti. Konjugacija ovih molekula s monosaharidima, osobito D-manozom, omogućuje njihovo prepoznavanje i unos u stanice putem manoznih receptora koji se nalaze na površini makrofaga i dendritičkih stanica. Ovakav pristup otvara mogućnosti za specifično usmjeravanje imunološkog odgovora, smanjenje nuspojava i povećanje učinkovitosti terapije. Ključni koraci u sintezi ovakvih konjugata uključuju odgovarajuću zaštitu hidroksilnih skupina manoze, pripravu odgovarajućeg glikozida i kontroliranu formaciju amidne veze između šećernog i peptidnog dijela molekule.Immunomodulators based on muramyl-dipeptide (MDP) and its derivatives
represent a significant class of compounds in the development of modern vaccines and immunotherapies. Among them, desmuramyl-peptides have attracted attention due to their improved stability and targeted biological activity. The conjugation of these molecules with monosaccharides, particularly D-mannose, enables their recognition and uptake by cells via
mannose receptors located on the surface of macrophages and dendritic cells. This approach offers opportunities for the specific targeting of immunologically active molecules, reducing side effects and increasing therapeutic efficacy. Key steps in the synthesis of such conjugates include the appropriate protection of hydroxyl groups on mannose and the controlled formation of an amide bond between the monosaccharide and peptide portions of the molecule
Characterization of hydrazide macrocyclic and acyclic compounds by electrochemical, spectrophotometric and potentiometric methods
No full textU ovom radu ispitana su elektrokemijska svojstva hidrazidnih derivata dipikolinske kiseline pri čemu je analiziran jedan makrociklički i jedan aciklički spoj. Najprije su u radu definirani najpogodnija radna elektroda i elektrolit. Ispitana su elektrokemijska svojstva svakog od derivata te su ispitane sposobnosti kompleksiranja s bakrovim(II) ionom u tri različita medija: vodenom mediju, DMSO te Tris-puferu pri pH = 9. U Tris-puferu pri pH = 9 uočena je promjena boje otopine prilikom priprave otopine acikličkog spoja s bakrovim(II) ionima u omjeru 1:1 te makrocikličkog spoja s bakrovim(II) ionima u omjeru 2:1. Navedeni omjeri metal: ligand su utvrđeni i spektrofotometrijski pomoću Jobove metode, a iz dobivenih rezultata određena je logaritamska vrijednost konstante stabilnosti koja je iznosila, log K = 5,46 za
kompleks acikličnog spoja s Cu2+ ionom te log K = 5,34 za kompleks makrocikličkog spoja s Cu2+ ionom što ukazuje na stabilnost oba kompleksa. Potenciometrijskim titracijama izračunata je vrijednost konstante stabilnosti za kompleks acikličkog liganda s bakrovim(II) ionima u omjeru 1:1, dok se za kompleks makrocikličkog liganda s bakrovim(II) ionima određivanje konstante stabilnosti nije bilo moguće jer nije detektirana točka ekvivalencije.In this study, the electrochemical properties of dipicolinic acid hydrazide derivatives were investigated, with one macrocyclic and one acyclic compound. Firstly, the most suitable working electrode and electrolyte were defined. Secondly, the electrochemical properties of each derivative were examined and the complexation capabilities with copper (II) ion were tested using three different media: aqueous medium, DMSO, and Tris buffer at pH = 9. In Tris buffer at pH = 9, a colour change was observed when preparing a solution of the acyclic compound with copper (II) ion in a 1:1 ratio with the macrocyclic compound and copper (II) ion in a 2:1 ratio. The above metal:ligand ratios were also determined spectrophotometrically using the Job method, and from the obtained results the logarithmic value of the stability constant was determined, which was log K = 5.46 for the complex of the acyclic compound with the Cu2+ ion and log K = 5.34 for the complex of the macrocyclic compound with the Cu2+ ion, indicating the stability of both complexes. Using potentiometric titration, the value of the stability constant was successfully calculated for the complex of the acyclic ligand and the copper (II) ion in the ratio 1:1, while the stability constant could not be obtained for the complex of the macrocyclic ligand and the copper (II) ion because the equivalence point was not detected
Application of data mining and artificial intelligence in the search for new synthetic pathways in organic chemistry
No full textOrganska kemija, kao disciplina usmjerena na dizajn i sintezu novih kemijskih spojeva, suočava se s izazovima u identifikaciji i optimizaciji sintetskih puteva. S obzirom na kompleksnost kemijskih reakcija i potrebu za visokim stupnjem preciznosti, tradicionalne metode eksperimentalnog istraživanja često su dugotrajne i skupe. U tom kontekstu, rudarenje podataka (engl. Data mining) i umjetna inteligencija (engl. Artificial Intelligence, AI) nude inovativne pristupe za unapređenje i ubrzanje procesa traženja novih sintetskih puteva. Kroz analizu povijesnih podataka o kemijskim reakcijama, data mining može pomoći u identifikaciji uspješnih sintetskih ruta, uzoraka u reakcijskim uvjetima i veza između strukturiranih karakteristika molekula i njihovih reaktivnosti. Primjena data mininga omogućuje znanstvenicima da automatski prepoznaju obrasce u velikim bazama podataka o kemijskim reakcijama i strukturama. Ovo omogućava identificiranje potencijalnih novih sintetskih puteva koji bi inače mogli proći neprimijećeni. Na primjer, analiza uspješnih reakcija u kombinaciji s podacima o uvjetima sinteze može pomoći u otkrivanju novih reagensa ili metoda koje poboljšavaju učinkovitost reakcija. U fokusu završnog rada nalazi se istraživanje primjene metoda data mininga i AI
u otkrivanju novih sintetskih puteva u organskog kemiji. Namjera je istaknuti vrijednosti i primjenjivosti naprednih analitičkih tehnika u području organske kemije.Organic chemistry, as a discipline focused on the design and synthesis of new chemical compounds, faces significant challenges in identifying and optimizing synthetic pathways. Due to the complexity of chemical reactions and the requirement for a high degree of precision, traditional experimental methods are often time-consuming and costly. In this context, data mining and artificial intelligence (AI) offer innovative approaches to enhance and accelerate the discovery of new synthetic
routes. By analyzing historical data on chemical reactions, data mining can help identify successful synthetic routes, recognize patterns in reaction conditions, and uncover correlations between molecular structural features and their reactivity. The application of data mining enables researchers to
automatically detect patterns in large chemical reaction and structural databases, allowing for the identification of potential new synthetic pathways that might otherwise remain unnoticed. For example, the analysis of successful reactions combined with reaction condition data can help reveal new reagents or methods that improve reaction efficiency. This thesis focuses on exploring the application of data mining and AI in the discovery of new synthetic pathways in organic chemistry. The aim is to highlight
the value and applicability of advanced analytical techniques in this scientific field
Green synthesis of silver nanoparticles by using Knopper Gall extracts
No full textNanočestice srebra u ovom radu dobivene su postupkom zelene sinteze uz upotrebu
ekstrakta šiške hrasta lužnjaka. Šiška, nepravilna izraslina na plodu hrasta, se pokazala odličnim izborom biljnog ekstrakta za sintezu nanočestica zbog svojih brojnih fitokemijskih svojstava. Nanočestice srebra uspješno su sintetizirane iz ekstrakta hrastove šiške i otopine srebrova nitrata. Sintetizirane nanočestice srebra karakterizirane su UV-Vis spektroskopijom, ATR-FTIR spektroskopijom, rendgenskom difrakcijom na prahu – PXRD, TEM analizom, te je provedena mikrobiološka analiza. Veličina nanočestica srebra, izračunata Scherrerovom jednadžbom, iznosila je 12 nm. Dobivene nanočestice također pokazuju antibakterijsku aktivnost protiv bakterija Bacillus subtilis, Staphylococcus aureus, Escherichia coli i Pseudomonas aeruginosa.Silver nanoparticles in this study were obtained through green synthesis using the extract of Quercus robur Knopper galls. The gall, an irregular outgrowth formed on the oak acorn, proved to be an excellent choice of plant extract for nanoparticle synthesis due to its rich phytochemical composition. Silver nanoparticles were successfully synthesized using
Knopper gall extract and silver nitrate. The synthesized nanoparticles were characterized using UV-Vis spectroscopy, ATR-FTIR spectroscopy, powder X-ray diffraction - PXRD and transmission electron microscopy - TEM, while a microbiological analysis was also conducted. The size of the silver nanoparticles, calculated using Scherrer’s equation, was determined to be approximately 12 nanometers. Furthermore, the obtained nanoparticles
exhibited antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa
Gut microbiota: metabolism and absorption of nutrients
No full textCrijevna mikrobiota je naziv za mikroorganizme koji koloniziraju probavni sustav. Njezin razvoj započinje s rođenjem, a dalje se tijekom života mijenja pod utjecajem različitih čimbenika od kojih je najvažnija prehrana. U tijelu čovjeka obavlja brojne funkcije, a neke od njih su antimikrobna zaštita, imunomodulacija te metabolizam i apsorpcija lijekova i nutrijenata. Glavni crijevni mikroorganizmi pomažu u razgradnji ugljikohidrata, a produkti tog procesa su kratkolančane masne kiseline. Osim ugljikohidrata, sudjeluju i u razgradnji proteina te sintezi vitamina kao što je vitamin B. Apsorpcijom nutrijenata, primjerice minerala, dobivaju energiju koju dalje troše za različite procese. Poremećaj ravnoteže crijevne mikrobiote koji je poznat kao disbioza ima značajne posljedice na ljudsko zdravlje, a jedna od mogućih posljedica je razvoj pretilost.Gut microbiota is the name for the microorganisms that colonize the digestive system. Its development begins at birth and continues to change throughout life under the influence of various factors, the most important of which is nutrition. It performs numerous functions in the human body, some of which are antimicrobical protection, immunomodulation and the metabolism and absorption of drugs and nutrients. The main intestinal microorganisms assist in the breakdown of carbohydrates, producing short-chain fatty acids as end-products of this process. In addition to carbohydrates, they are also involved in protein degradation and the synthesis of vitamins, such as vitamin B. Through absorption of nutrients, such as minerals, they obtain energy that they later use for various metabolic processes. Disruption in the balance of the gut microbiota, known as dysbiosis, has significant consequences for human health, and one of the possible consequences is the development of obesity
Application of metal-organic frameworks for detection of gases
No full textMetalo-organske mreže su kemijski spojevi građeni od metalnog centra koji je
koordinacijski vezan s organskim ligandima. Metalni centar može biti građen od jednog metalnog iona ili više metalnih iona koji tvore metalni klaster. Jako lako se sintetiziraju i većina metoda je ekološki prihvatljiva i ne zahtijeva velike količine energije za sintezu. Imaju veliku primjenu u adsorpciji plinova. Fizikalnom adsorpcijom i kemisorpcijom na sebe privlače ciljane plinove iz smjese plinova. Metalo-organske mreže su jako specifične i osjetljive što znači da mogu adsorbirati specifične plinove prisutne u jako malim koncentracijama u zraku. Mogu se koristiti za detekciju puno različitih plinova, a neki od njih su ugljikov monoksid, metan, vodik i ugljikov dioksid. Moć adsorpcije metalo-organskih mreža se najčešće ispituje spektroskopskim metodama i analizom plinsko-adsorpcijskih izotermi. Nedostatci metalo-organskih mreža su to što im vlaga i visoka temperatura smanjuju adsorpciju plinova. U industriji se mogu koristiti kao detektori plinova, u medicini kao prijenosnici lijekova do aktivnog mjesta te se koriste za praćenje kvalitete zraka.Metal-organic frameworks are chemical compounds built from a metal center that is coordinatively bound to organic ligands. A metal center can be built from one metal ion or several metal ions that create a metal cluster. They are very easy to synthesize and most methods are environmentally friendly and do not require large amounts of energy for
synthesis. They are widely used in gas adsorption. By physical adsorption and chemisorption, they attract target gases from the gas mixture. Metal-organic frameworks are very specific and sensitive, which means they can adsorb specific gases present in very low concentrations in the air. They can be used to detect many different gases, some of which are carbon monoxide, methane, hydrogen and carbon dioxide. The adsorption power of metal-organic networks is most often tested by spectroscopic methods and analysis of gas adsorption isotherms. The disadvantages of metal-organic networks are that moisture and high temperature reduce gas adsorption. In industry, they can be used as gas detectors, in medicine, they are used as drug carriers to the active site and for air quality monitoring
Green synthesis of nanoparticles from plant extracts used in traditional medicine
No full textZelena sinteza predstavlja ekološki prihvatljiv, jednostavan i jeftin pristup sintezi metalnih nanočestica korištenjem biljnih ekstrakata bogatih bioaktivnim spojevima. U ovom radu provedena je sinteza nanočestica srebra pomoću ekstrakta biljke planinski koprenjak (Ligusticum mutellina (L.) Crantz), poznate u narodnoj medicini i vodene otopine AgNO3. Uspješnost sinteze nanočestica srebra potvrđen je UV-Vis spektroskopijom, FT-IR analizom i rendgenskom difrakcijom na prahu (PXRD). Dodatno je istražena i antioksidacijska aktivnost mjerenjem DPPH, FRAP i ukupnih topljivih polifenola, a najbolji rezultat su pokazale sjemenke biljke. UV-Vis spektar pokazao je apsorpcijski maksimum oko 407 nm, a PXRD analiza prosječnu velič inu kristalita od približno 11 nm. Dobiveni rezultati potvrđuju uspješnu biosintezu i potencijal biljke (Ligusticum mutellina (L.) Crantz za održivu primjenu u nanotehnologiji.Green synthesis represents an environmentally friendly, simple and inexpensive approach to the synthesis of metal nanoparticles using plant extracts rich in bioactive compounds. In this work, the synthesis of silver nanoparticles was carried out using an extract of the mountain milkweed plant (Ligusticum mutellina (L.) Crantz), known in traditional medicine, and an aqueous solution of AgNO3. The success of the synthesis of silver nanoparticles was confirmed by UV-Vis spectroscopy, FTIR analysis and powder X-ray diffraction (PXRD). Additionally, antioxidant activity was investigated by measuring DPPH, FRAP and total soluble polyphenols, and the best result was shown by the seeds of the plant. The UV-Vis spectrum showed an absorption maximum around 407 nm, and PXRD analysis showed an average crystallite size of approximately 11 nm. The obtained results confirm the successful biosynthesis and the potential of Alpine lovage (Ligusticum mutellina (L.) Crantz) for sustainable application in nanotechnology
Synthesis and characterization of hydroxyapatite from natural calcium carbonate
No full textHidroksiapatit (HAP), spoj kemijske formule Ca10(PO4)6(OH)2, jedan je od najznačajnijih biomaterijala zbog svoje iznimne biokompatibilnosti te strukturne sličnosti s mineralnim dijelom ljudske kosti. Ovaj završni rad usmjeren je na istraživanje temeljnih fizikalno-kemijskih svojstava HAP-a, njegove kristalne strukture, metoda sinteze te širokog spektra primjene u biomedicini, osobito u regeneraciji tvrdih tkiva. Posebna pozornost posvećena je metodi taloženja, u kojoj se fosforna kiselina postupno dodaje u suspenziju kalcijeva hidroksida, što rezultira dobivanjem hidroksiapatita u obliku praha. Važno je istaknuti da je kalcij korišten u ovom procesu dobiven iz prirodnog izvora, kalcijevog karbonata izoliranog iz ljuski kokošjih jaja, čime se dodatno ističe održivost i ekološka prihvatljivost korištene metode. U eksperimentalnom dijelu provedena je laboratorijska sinteza HAP-a, a karakterizacija dobivenog uzorka napravljena je pomoću rendgenske difrakcije na polikristalnom uzorku (PXRD), infracrvene spektroskopije s Fourierovom transformacijom (FT-IR) te analizom površinskih svojstava Brunauer-Emmett-Teller metodom (B.E.T.). Rezultati analiza potvrdili su formiranje kristalne faze tipične za HAP te prisutnost funkcijskih skupina karakterističnih za navedeni spoj. Dobiveni hidroksiapatit pokazuje visoku razinu čistoće i fizikalno-kemijska svojstva pogodna za biomedicinske primjene. Korištena metoda sinteze pokazala se jednostavnom, ekonomičnom i učinkovitom, čime se potvrđuje njezina prikladnost za daljnji razvoj funkcionalnih biomaterijala, osobito u dentalnoj i ortopedskoj medicini.Hydroxyapatite (HAP), a compound with the chemical formula Ca10(PO4)6(OH)2, is one of the most important biomaterials due to its exceptional biocompatibility and structural similarity to the mineral component of human bone. This thesis deals with the investigation of the basic physico-chemical properties of HAP, its crystal structure, the synthesis methods and its various applications in biomedicine, especially in hard tissue regeneration. Particular attention is paid to the precipitation method, in which phosphoric acid is gradually added to a calcium hydroxide suspension, resulting in the formation of hydroxyapatite in powder form. It is important to mention that the calcium used in this process comes from a natural source, namely calcium carbonate extracted from chicken eggshells, which emphasises the sustainability and environmental friendliness of the method used. In the experimental part, HAP was synthesised in the laboratory and the resulting sample was characterised using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and surface analysis using the Brunauer-Emmett-Teller (B.E.T.) method. The analysis confirmed the formation of a crystalline phase typical of HAP and the presence of the functional groups characteristic of this compound. Thesynthesised hydroxyapatite exhibited high purity and physicochemical properties suitable for biomedical applications. To summarise, the synthesis method used proved to be simple, cost-effective and efficient, which confirms its suitability for the further development of functional biomaterials, particularly in dentistry and orthopaedics