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    SYNTHESIS OF SOME QUINAZOLINONE DERIVATIVES USING GREEN SYNTHETIC METHODS – A COMPARISON OF MECHANOSYNTHESIS AND ULTRASOUND ASSISTED SYNTHESIS

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    Kako bi se smanjio negativan utjecaj na okoliš, unazad nekoliko godina zelena kemija ubrzano napreduje. Blaţi uvjeti reakcije, redukcija štetnih otapala, veća iskorištenja i kraće reakcijsko vrijeme su sve prednosti zelenih metoda sinteze u odnosu na konvencionalne. Sinteza potpomognuta ultrazvukom i mehanokemijska sinteza jedne su od zelenih metoda korištenih u ovomu radu. Te metode su primjnjene za sintezu 20 različitih derivata Schiffovih baza. Schiffove baze su vaţna skupina spojeva jer pokazuju antiupalna, antibakterijska, antivirusna, antikancerogena, antitumorska i mnoga druga pozitivna svojstva. Ţeljene Schiffove baze sintetizirane su iz prekurzora 3-amino-2-metilkinazolin-4(3H)-ona i različito supstituiranih aromatskih aldehida u različitom rasponu iskorištenjIn order to prevent a negative impact on environment, green chemistry is being rapidly developed. Milder reaction conditions, reduction of harmful solvents, higher yields and shorter reaction time are all benefits of green chemistry in comparison to the conventional methods. Ultrasound assisted synthesis and mechanochemical synthesis are green chemistry methods used in this research. Using these methods, twenty different Schiff bases were synthesised. Schiff bases are desirable compounds due to their anti-inflamtory, antibacterial, anti-viral, anri-cancer, anti-tumor and many other positive properties. Schiff bases were synthesized from 3-amino-2-methyl-quinazolin-4(3H)-one and substitued aromatic aldehydes in different yields

    The Influence of Replacing Milk Powder with Hazelnut Cake on the Physicochemical Properties of Ice Cream

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    Pogača lješnjaka je nusproizvod dobiven proizvodnjom hladno prešanog ulja lješnjaka. S obzirom da je bogat izvor mnogih vrijednih nutrijenata, njena upotreba kao dodatka ili sirovine u proizvodnji funkcionalnih proizvoda sve je češća. Dodatno, iskorištenjem pogače lješnjaka rješava se problem zbrinjavanja ovog nusproizvoda koji nastaje u velikim količinama. Zadatak ovog rada bio je ispitati utjecaj djelomične ili potpune zamjene obranog mlijeka u prahu pogačom lješnjaka na kakvoću mliječnog sladoleda. U tu svrhu, proizveden je sladoled s 25 %-tnom, 50 %-tnom, 75 %-tnom i 100 %-tnom zamjenom mlijeka u prahu, te kontrolni uzorak (bez zamjene mlijeka u prahu). Nakon proizvodnje sladoleda i 24-satnog dubokog zamrzavanja, ispitala su se fizikalno-kemijska svojstva istog. Zamjena obranog mlijeka u prahu pogačom lješnjaka utjecala je na reološka svojstva sladoledne smjese, linearno povećavajući koeficijent konzistencije. Također, povećanje udjela pogače lješnjaka dovelo je do smanjenja povećanja volumena (tzv. overrun), a shodno tome, do povećanja tvrdoće sladoleda. Zamjena mlijeka u prahu pogačom lješnjaka nije imala utjecaj na ispitivane parametre topljenja. Svjetlina uzoraka opadala je proporcionalno dodatku pogače lješnjaka, dok je intenzitet crvene boje rastao. Na temelju dobivenih rezultata može se zaključiti da postoji mogućnost djelomične zamjene mlijeka u prahu pogačom lješnjaka s ciljem dobivanja sladoleda s potencijalnim funkcionalnim svojstvima.Hazelnut oil cake is a by-product obtained from the production of cold-pressed hazelnut oil. Given that it is a rich source of many valuable nutrients, its use as a supplement or raw material in the production of functional products is increasingly common. In addition, the use of hazelnut cake solves the problem of disposal of this by-product, which is produced in large quantities. This work aimed to examine the influence of partial or complete replacement of skimmed milk powder with hazelnut cake on the quality of milk ice cream. For this purpose, ice cream was produced with 25%, 50%, 75%, and 100% replacement of milk powder (control sample, i.e. sample without replacement of milk powder was also produced). After the production of ice cream and 24-hour hardening, its physical and chemical properties were examined. The replacement of skimmed milk powder with hazelnut cake affected the rheological properties of the ice cream mixture, linearly increasing the consistency coefficient. Also, an increase in the concentration of hazelnut cake led to a decrease in overrun, and, accordingly, to an increase in the hardness of the ice cream. Replacing milk powder with hazelnut cake did not affect examined melting properties. The brightness of the samples decreased due to the addition of hazelnut cake, while the redness increased. Based on the obtained results, it can be concluded that there is a possibility of replacing milk powder with hazelnut cake, in order to obtain ice cream with potential functional properties

    The Influence of the Addition of Hempseed Cake on the Physicochemical Properties of Ice Cream

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    Sladoled je kompleksni sustav koji se najčešće sastoji od mliječnih komponenti, zaslađivača, stabilizatora, emulgatora i aroma te inkorporiranog zraka. Pogača konoplje je nusproizvod nastao tijekom proizvodnje hladno prešanog ulja industrijske konoplje. Cilj ovog rada bio je ispitati mogućnost djelomične zamjene mlijeka u prahu u sladoledu s pogačom industrijske konoplje te ispitati njegova fizikalno-kemijska svojstva. Pogača industrijske konoplje dodavala se u udjelima 25 %, 37,5 % i 50 % od ukupnog udjela mlijeka u prahu. Proizvodnja uzoraka sladoleda provodila se u uređaju Nemox GELATO 5K CREA i Green te su nakon toga provedene analize fizikalno-kemijskih parametara sladoleda. Rezultati su pokazali da povećanje udjela pogače industrijske konoplje u sladoledu utječe na njegov kemijski sastav te na povećanje koeficijenta konzistencije, aktiviteta vode i pH vrijednosti sladoleda. Nadalje, sladoledi obogaćeni pogačom industrijske konoplje imali su veće vrijednosti povećanja volumena, a manje vrijednosti indeksa destabilizacije masti i tvrdoće. Parametri boje promijenjeni su u skladu s povećanjem udjela pogače industrisjke konoplje.Ice cream is a complex medium mostly consisting of milk ingredients, sweeteners, stabilizers, emulsifiers, flavoring, and incorporated air. The hemp press cake is a by-product obtained during cold pressing of industrial hemp. The aim of this study was to examine the possibility of partial substitution of milk powder in ice cream with hemp press cake and to research the influence of this substitution on the physicochemical properties of ice cream. Industrial hemp press cake was added in proportions of 25%, 37.5%, and 50% of the total proportion of milk powder. The manufacturing of the ice cream samples was carried out in a Nemox GELATO 5K CREA i-Green machine. After production, analyses of the physicochemical parameters of the ice cream samples were carried out. The results showed that increasing the proportion of hemp press cake in ice cream affects its chemical composition and increases the consistency coefficient, water activity, and pH value of the ice cream. Ice creams enriched with hemp press cake had higher values of overrun and lower values of fat destabilization and hardness indices. The color parameters were changed in accordance with the increase in the proportion of hemp press cake

    COUMARIN IN CINNAMON CONTAINING FOOD – EXTRACTION AND HPLC DETERMINATION

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    Cimet, kao začin te kao dodatak različitim grupama namirnica kao što su pahuljice za doručak, čajevi te pekarski proizvodi predstavlja važan dio prehrane. Cimet u svom sastavu, između brojnih bioaktivnih komponenti, sadržava i važan aktivni spoj kumarin. Za kumarin brojna istraživanja pokazuju kako ima povoljan zdravstveni učinak na organizam u optimalnoj koncentraciji, no povećana dugoročna konzumacija može dovesti do nepovoljnih utjecaja na zdravlje. U ovom završnom radu istraživala se koncentracija kumarina u deset različitih namirnica koje se nalaze na hrvatskom tržištu, uključujući mljevene začine i čajeve. Također, analizirani se različiti parametri ekstrakcije u svrhu pronalaska najbolje metode ekstrakcije kumarina iz cimeta i proizvoda koji sadrže cimetCinnamon, as a spice and as an additive to various food groups, such as breakfast cereals, teas and bakery products, is an important part of the human diet. Cinnamon in its composition, among many bioactive components, contains an important active compound coumarin. Numerous studies have shown that coumarin has a beneficial health effect on the body in optimal concentration, but its increased long-term consumption can lead to adverse health effects. In this bachelor thesis, the level of coumarin in ten different foods found on the Croatian market, including ground spices and teas, was analyzed. Also, different extraction parameters were analyzed in order to find the best method of extraction of coumarin from cinnamon and products containing cinnamon

    NUTRITIONAL QUALITY OF WHEAT SEEDLINGS BIOFORTIFIED WITH IODINE

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    Jod kao esencijalni element sudjeluje u normalnom funkcioniranju organizma, a naročito štitne žlijezde gdje je neophodan za sintezu tiroksina te trijodtironina. Malnutricija uzrokovana neadekvatnim unosom joda može se spriječiti biofortifikacijom usjeva, kao i različitim dodacima prehrani. Stoga je cilj ovog rada bio pšeničnu travu koja se često koristi kao dodatak prehrani, obogatiti jodom. Pšenična trava bogata je vitaminima, mineralima, fenolnim spojevima te joj se pripisuju brojna pozitivna znanstveno potvrđena djelovanja na ljudski organizam. Nutritivna vrijednost, u ovom istraživanju, vrednovana je mjerenjem količine vitamina C, ukupnih fenola, klorofila, karotenoida, ukupnih šećera i celuloze te ukupne antioksidacijske aktivnosti. Povećanjem koncentracije kalijeva jodida, koji se koristio za biofortifikaciju pšenične trave, povećavala se i količina vitamina C, proteina, klorofila i ukupnih šećera u pšeničnoj travi. S druge strane, visoke koncentracije pokazale su se toksičnima budući da je došlo do smanjenja biomase i klijavosti pšenice. Stoga, pšenična trava obogaćena jodom zbog svoje nutritivne vrijednosti ima potencijal za upotrebu u svakodnevnoj prehrani ili za liječenje malnutricije.As an essential element, iodine participates in the normal functioning of the organism, especially the thyroid gland, where it is necessary for the synthesis of thyroxine and triiodothyronine. Malnutrition caused by inadequate iodine intake can be prevented by crop biofortification as well as various dietary supplements. Therefore, the aim of this work was to enrich wheatgrass which is often used as a dietary supplement with iodine. Wheatgrass is rich in vitamins, minerals, phenolic compounds and is attributed to many positive scientifically proven effects on the human body. Nutritional value, in this study, was evaluated by measuring the amount of vitamin C, total phenols, chlorophyll, carotenoids, total sugars and cellulose, and total antioxidant activity. By increasing the concentration of potassium iodide, which was used for the biofortification of wheatgrass, the amount of vitamin C, protein, chlorophyll and total sugars in wheat grass also increased. On the other hand, high concentrations proved to be toxic as there was a decrease in wheat biomass and germination. Therefore, wheatgrass enriched with iodine due to its nutritional value has the potential for use in the daily diet or for the treatment of malnutrition

    The role of epigenetics in ecology and evolution

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    Epigenetičke promjene imaju značajan utjecaj na evolucijski proces, njihovo djelovanje na specijaciju i prirodnu selekciju je posredovano okolišnim faktorima i time su usko povezane s ekologijom i evolucijom. U radu je dan pregled znanstvenih istraživanja čija tematika istražuje uzajamno djelovanje okolišnih čimbenika i fenotipskih promjena te njihov utjecaj na evolucijski proces. Također, na koji način promjene okolišnih čimbenika uzrokuju promjene u genskoj zalihi populacije te njihov utjecaj na socijalnu dinamiku populacije i potencijalno specijaciju.Epigenetic changes have a significant impact on the evolutionary process, their effect on speciation and natural selection is mediated by environmental factors and are thus closely related to ecology and evolution. The paper presents an overview of scientific research whose topic investigates the interaction of environmental factors and phenotypic changes and their impact on the evolutionary process. Also, how changes in environmental factors cause changes in the gene pool of the population and their impact on the social dynamics of the population and potentially speciation

    REACTIONS OF WINTER WHEAT SEEDLINGS TO PHYSIOLOGICAL DROUGHT: THE POSSIBILITY OF EARLY SCREENING OF SENSITIVE AND TOLERANT GENOTYPES

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    Osjetljivost biljaka na sušu genetski je predodređena u fenološkim, fiziološkim, biokemijskim i molekularnim svojstvima, a genetsko poboljšanje otpornosti zahtijeva identificiranje odgovarajućih mehanizama koji sudjeluju u inhibiranju ili ublažavanju štetnih učinaka stresa izazvanog nedostatkom vode. Tri dana stari klijanci 18 različitih sorti ozime pšenice izloženi su uvjetima vodnog deficita tijekom sedam dana (ψ = -0,3 MPa) uz pomoć polietilenglikola (PEG-6000). Istraživanje je obuhvatilo morfološke (visina izdanka i duljina korijena), fiziološke i biokemijske (relativni sadržaj vode, oštećenost biomembrana, razina lipidne peroksidacije, sadržaj slobodnog prolina, koncentracija fotosintetskih pigmenata) te fluorometrijske parametre (fluorescencija klorofila a). Multivarijantna analiza otkrila je da je potrebna potpuna interakcija složene kolekcije svojstava koje omogućuju prilagodbu na sušu kako bi se identificirali mehanizmi koji najbolje objašnjavaju varijabilnost među ispitivanim sortama. Fluorescencija klorofila a pokazala se kao najefikasnija metoda za rani probir osjetljivih i tolerantnih genotipova, ali ipak kombinacija parametara fluorescencije i određenih biokemijskih parametra ključna je za uspješnost oplemenjivačkog programa. Istraživanja utjecaja okolišnih stresora (poput suše) na rani rast klijanaca mogu upotpuniti znanja potrebna za rješavanje nekih temeljnih pitanja, kao što je stupanj plastičnosti, kako kod mladih nerazvijenih, tako i potpuno razvijenih biljaka.Plant susceptibility to drought is genetically predetermined in phenological, physiological, biochemical, and molecular properties, and genetic improvement of drought resistance requires identification of appropriate mechanisms involved in inhibiting or mitigating the adverse effects of drought stress. Three-day-old seedlings of 18 different winter wheat cultivars were exposed to water deficit conditions for seven days (ψ = −0.3 MPa) using polyethylene glycol (PEG-6000). The study included measurements of morphological (shoot and root length), physiological and biochemical (relative water content, membrane leakage, lipid peroxidation level, free proline content, photosynthetic pigment concentration, and chlorophyll a fluorescence. Multivariate analysis revealed that the complete interaction of a complex collection of drought-adapting traits is needed to identify the parameters that best explain the variability among the studied cultivars. Chlorophyll a fluorescence appeared to be the most effective method for early screening of sensitive and tolerant genotypes. However, a combination of particular chlorophyll a fluorescence test parameters and specific biochemical parameters is vital for a successful breeding program. Research on the impact of environmental stressors (such as drought) on early seedling growth can complement the knowledge needed to address some fundamental issues, such as the degree of plasticity, in both young as well as fully developed plants

    INVENTARIZATION OF THE AQUATIC INSECTS (HETEROPTERA AND COLEOPTERA) IN THE AREA OF BILJSKI RIT WITH SPECIAL REFERENCE TO PROTECTED SPECIES GRAPHODERUS BILINEATUS (DE GEER, 1774)

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    Inventarizacija vodenih kukaca (Heteroptera, Coleoptera) provedena je na vodenim staništima Biljskog rita u vremenskom periodu od travnja do kraja srpnja 2020. godine. Korištene su dvije metode uzorkovanja, metoda aktivnog poteza mrežom i metoda klopka – boca s atraktantom. Ukupno je prikupljeno 1420 jedinki svrstanih u 11 porodica, odnosno 46 vrsta. Redu Heteroptera (vodene stjenice) pripa da sedam vrsta, a redu Coleoptera (vodeni kornjaši) pripada 39 vrsta. Tri porodice su eudominantne, a dvije porodice: Dytiscidae i Hydrophilidae, eudominantne su na svim postajama. Sörensenov indeks sličnosti pokazuje veliku sličnost između istraživanih postaja te tako indeks za postaja Kopačevo kanal – bara i Jaje bara iznosi 75%. Vrsta Laccophilus hyalinus jedina je eukonstantna vrsta na ovome području. Zaštićena vrsta Graphoderus bilineatus zabilježena je na svim istraživanim postajama, a ukupno je uzorkovano 48 jedinki. Pronalaskom vrste Graphoderus bilineatus prošireno je područje rasprostranjenosti ove vrste na području Hrvatske te se ukazuje na važnost revitalizacije istraživanog područja čime bi se povećala i brojnost vrste. Broj stranica: 52The inventory of water beetles and water bugs (Heteroptera, Coleoptera) was carried out between April and the end of July 2020. on aquatic habitats of Biljski rit. Two sampling methods were used, hand net method and bottle trap method with atractants. The total of 1420 samples was collected, divided into 11 families, 46 species respectively. To the order Heteroptera (water bugs) appertain seven species, whereas to the order of Coleoptera appertain 39 species. Three families are the most abundant, and two families: Dytiscidae and Hydrophilidae are eudominant on every station. Sörensen similarity index displays immense similarities between explored stations. Thus, the index for station Kopačevo canal – temporary pond and Jaje bara result with 75%. Laccophilus hyalinus species is the only euconstant species in this area. Protected species Graphoderus bilineatus was recorded in every station explored, and a total of 48 samples were collected. Graphoderus bilineatus species findings implied extended diffusion area of this species on the Croatian territory, hence pointing out the importance of revitalisation of the explored area, by which abundance of the species would increase

    The Effect of Storage Temperature on Physical Properties of Turmeric and Black Pepper Ice Cream

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    U ovom radu je ispitan utjecaj dviju različitih temperatura skladištenja na stabilnost i kakvoću sladoleda nakon tri mjeseca skladištenja. Proizvedeni uzorci s dodatkom kurkume u udjelima 0,5 %, 1,0 %, 2,0 %, bez ili s 0,02 % crnog papra uspoređivani su sa kontrolnim uzorkom. Provedene su fizikalne analize povećanje volumena, analiza boje i analiza profila teksture. Rezultati istraživanja pokazali su linearno povećanje volumena sladoleda s povećanjem udjela kurkume i dodatan rast vrijednosti dodatkom crnog papra. Vrijednosti L* su obrnuto proporcionalne povećanju udjela kurkume i dodatku crnog papra. Pad vrijednosti L* ukazuje na smanjenje svjetline boje, dok su vrijednosti za a* i b* proporcionalne povećanju udjela kurkume i dodatku crnog papra pri obje temperature skladištenja. Povećanje vrijednosti ukazuje na promjenu boje. Skladištenje na nižoj temperaturi smanjilo je pad vrijednosti za L*, a* i b*. Povećanjem udjela kurkume i dodatkom crnog papra u uzorke opadaju vrijednosti za tvrdoću, kohezivnost, gumenost, dok vrijednosti za adhezivnost rastu. Na osnovi dobivenih rezultata može se zaključiti da se kurkuma i papar mogu koristiti u proizvodnji funkcionalnog sladoleda s prihvatljivim fizikalnim svojstvima.This research examined the impact of two different storage temperatures on the stability and quality of ice cream after three months of storage. Produced samples with turmeric added at concentrations of 0.5%, 1.0%, and 2.0%, with or without 0.02% black pepper, were compared to a control sample. Physical analyses including overrun, colour analysis, and texture profile analysis were conducted. The results indicated a linear increase in ice cream volume with increasing turmeric content, with an additional increase in value with the addition of black pepper. The L* values were inversely proportional to the increase in turmeric content and the addition of black pepper, indicating a decrease in colour brightness. The a* and b* values were proportional to the increase in turmeric content and the addition of black pepper at both storage temperatures, indicating a colour change. Storage at a lower temperature reduced the decline in L*, a*, and b* values. Increasing the turmeric content and adding black pepper to the samples decreased hardness, cohesiveness, gumminess, while adhesiveness values increased. In conclusion, turmeric and pepper can be used in the production of functional ice cream with acceptable physical properties

    Application of Computer Vision for Determining Melting Properties of Ice Cream

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    Budući da je sladoled unutar kategorije smrznutih mliječnih deserata proizvod koji se najviše konzumira, cilj je dobiti što kvalitetniji proizvod. Topljivost sladoleda je njegova vrlo bitna karakteristika te se najčešće kao pokazatelj određuje brzina topljenja. U ovom radu je za analizu svojstava topljenja korišteno sedam različitih uzoraka sladoleda sa i bez dodataka. Uz gravimetrijsku metodu za određivanje svojstava topljivosti primijenjene su i relativno novije metode računalne analize slike, pomoću kojih se određuju svojstva zadržavanja oblika odnosno svojstva širenja sladoleda. Rezultati dobiveni trima različitim metodama su uspoređeni kako bi se dobio uvid u podudarnost metoda. Mliječni sladoled bez dodataka pokazuje svojstva bržeg početka topljenja i veće brzine topljenja, u usporedbi sa ostalim uzorcima. Najdulje zadržavanje oblika sladoleda tijekom topljenja zabilježeno je kod uzoraka s najvišim udjelom dodataka, dok je trend najbržeg širenja otopljenog sladoleda primijećen kod uzoraka bez ili s manjim udjelom dodataka. Podaci za topljenje sladoleda primjenom računalne analize slike pokazuju vrlo dobro slaganje s rezultatima dobivenim gravimetrijskom metodom, što ukazuje na to da je moguća primjena ove metode u ispitivanju svojstava topljenja sladoleda.Since ice cream is the most consumed product within the category of frozen dairy desserts, the goal is to get the highest quality product. The melting of ice cream is its very important characteristic, and the rate of melting is usually determined as an indicator. In this study, seven different samples of ice cream with or without supplementation were used to analyse the melting properties. In addition to the gravimetric method for determining melting properties, relatively newer methods of computer vision analysis were applied, which determine the retention of the shape and the spreading of melted ice cream. The results obtained by three different methods were compared in order to gain a better insight into the concordance of the methods. Milk ice cream without the addition showed the fastest start of melting, and a higher melting rate, compared to the other samples. The longest retention of the ice cream shape during melting was recorded for samples with the highest content of spices, while the trend of the fastest spread of melted ice cream was observed in samples with no or lower spices content. Ice cream melting data using computer vision analysis show a very good agreement with the results obtained by the gravimetric method, which indicates that this method can be used to test the melting properties of ice cream

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