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Lipidi izolirani iz biomase mikroalgi Nannochloropsis sp. predstavljeni su kao perspektivna sirovina za proizvodnju biodizela. U ovom radu proveden je fototrofni šaržni uzgoj s pritokom supstrata u otvorenom sustavu na izvornoj f/2 podlozi uz dodatak natrijevog bikarbonata te fototrofni šaržni uzgoj s pritokom supstrata u barbotirajućoj koloni na izvornoj f/2 podlozi bez dodatnog izvora ugljika. Tijekom uzgoja praćene su promjene udjela proteina, ugljikohidrata i lipida u izdvojenoj biomasi kao i sastav pigmenata te profil masnih kiselina u ukupnim lipidima. Utvrđeno je da u periodu smanjene koncentracije fosfora, metabolizam mikroalge se usmjerava prema akumulaciji lipida i ugljikohidrata kao rezervnih makromolekula uz smanjenje udjela proteina. Posljednjeg dana šaržnog uzgoja u otvorenom bazenu postignuta je koncentracija biomase od 0,515 g Lˉ¹, a maksimalna produktivnost biomase od 0,8796 mg Lˉ¹ hˉ¹ postignuta je osamnaestog dana uzgoja. Šaržnim uzgojem u barbotirajućoj koloni koncentracija biomase na kraju uzgoja iznosila je 0,458 g Lˉ¹, a produktivnost sinteze biomase tada je bila 0,8297 mg Lˉ¹ hˉ¹. Kemijska flokulacija sa željezovim (III) kloridom potvrđena je kao alternativna metoda za izdvajanje stanica mikroalgi. Naposljetku, u radu je predstavljen elaborat tehničko-tehnološkog rješenja postrojenja za proizvodnju biodizela. Lipids isolated from biomass of microalgae Nannochloropsis sp. are presented as a promising feedstock for biodiesel production. Cultivation methods used in this paper were phototrophic fed-batch cultivation with substrate inflow in an open pond system on the original f/2 medium with sodium bicarbonate and phototrophic fed-batch cultivation with substrate inflow on the original f/2 medium without supplementation of carbon source in a bubble column. Changes in the content of proteins, carbohydrates and lipids were monitored in the separated algae biomass during cultivation. The composition of pigments and the profile of fatty acids in total lipids were as well monitored simultaneously. During the period of reduced phosphorus concentration it was confirmed that metabolic responses of microalgae lead to the accumulation of lipids and carbohydrates as reserve macromolecules and to a decrease in protein content. On the last day of fed-batch cultivation in open pond, biomass concentration of 0,515 g Lˉ¹ was achieved. The maximum productivity of 0,8796 mg Lˉ¹hˉ¹ was achieved eighteenth day of cultivation. Additionally, on the last day of fed-batch cultivation in bubble column, biomass concentration was 0,458 g Lˉ¹ and productivity of biomass synthesis was 0,8297 mg Lˉ¹ hˉ¹. Chemical flocculation with iron (III) chloride has been confirmed as an alternative method for microalgae cell harvesting. Lastly, technical-technological solution for a biodiesel production facility was presented in this paper.

Lipidi čine oko 30 – 35 % kemijskog sastava čokolade, a značajni su za senzorska i reološka svojstva te stalibnost tijekom skladištenja. Udio lipida, kao i sastav masnih kiselina ovisi o vrsti čokolade (mliječna ili tamna), zatim da li je dodana zamjenska mast i vrsta dodane zamjenske masti. Zadatak diplomskog rada bio je odrediti sastav i udio masnih kiselina različitih vrsta čokolada metodom plinske kromatografije uz plameno-ionizacijski detektor. Analiza je provedena na 5 uzoraka tamne i 8 uzoraka mliječne čokolade s dodatkom različitih vrsta zamjenskih masti, emulgatora i komponenti mlijeka. Udio ukupnih lipida određen je metodom po Folch-u. Masne kiseline u lipidnoj frakciji transesterificirane su u metilne estere masnih kiselina sa hladnom otopinom KOH u metanolu. Rezultati su pokazali da tamne čokolade imaju veći udio ukupnih lipida od mliječnih čokolada što se može pripisati različitom udjelu dodane kakaove mase. Dominantne masne kiseline u svim uzorcima bile su palmitinska (C16:0), stearinska (C18:0) i oleinska kiselina (C18:1), dok su za čokolade sa dodatkom kokosovog ulja karakteristični veći udjeli laurinske (C12:0) i miristinske kiseline (C14:0). Lipids make about 30-35% of the chocolate chemical composition, and are important for sensory and rheological properties and stability during storage. The lipid content as well as the fatty acid composition depends on the type of chocolate (milk or dark), then whether the vegetable fat has been added and the type of added fat. The aim of this study was to determine the composition and content of fatty acids of different types of chocolates by gas chromatography with a flame-ionization detector. The analysis was performed on 5 samples of dark and 8 samples of milk chocolate with the addition of different types of cocoa butter equivalents, emulsifiers and milk components. The content of total lipids was determined by the Folch method. Fatty acids in the lipid fraction were transesterified into fatty acid methyl esters with a cold solution of KOH in methanol. The results showed that dark chocolates have a higher total lipid content than milk chocolates, which can be attributed to the different proportion of added cocoa mass. The dominant fatty acids in all samples were palmitic (C16:0), stearic (C18:0) and oleic acid (C18: 1), while chocolates with added coconut oil were characterized by higher content of lauric (C12: 0) and myristic acid (C14: 0).

Istražen je rast tri soja mikroalgi, D2-1, F10 i D10, na različitim izvorima ugljika pri miksotrofnim i heterotrofnim uvjetima uzgoja. Najveći prinos biomase za sva tri soja postignut je na melasi kao izvoru ugljika pri početnoj koncentraciji do 35 g L-1. Određen je učinak omjera izvora ugljika i dušika (C/N) u hranjivoj podlozi na rast i makromolekulski sastav stanične biomase mikroalge Chlamydomonas sp. pri različitim uvjetima uzgoja. Pri nižem omjeru C/N od 10 mol mol-1 zamijećeno je značajno nakupljanje i lipida i ugljikohidrata neovisno o načinu uzgoja. Međutim heterotrofni uvjeti uzgoja potaknuli su proizvodnju ugljikohidrata u stanicama mikroalge, dok su miksotrofni uvjeti uzgoja podupirali nakupljanje lipida. Proveden je jednostavni šaržni uzgoj mikroalge Chlamydomonas sp. s pritokom supstrata u cilju postizanja visoke koncentracije biomase. Zadnji dan uzgoja postignuta je maksimalna produktivnost biomase (1,10 g L-1 dan-1), ugljikohidrata (0,31 g L-1 dan-1) i lipida (0,14 g L-1 dan-1). The growth of three microalgal strains, D2-1, F10 and D10, on different carbon sources was studied under mixotrophic and heterotopic conditions. The highest biomass yield for all studied strains was obtained mixotrophically with molasses as carbon source at initial concentrations below 35 g L-1. The influence of the carbon to nitrogen (C/N) ratio of cultivation media on growth of Chlamydomonas sp. and macromolecular composition of cell biomass was assessed under different cultivation conditions. At lower C/N ratio of 10 mol mol-1 significant increase of both lipid and carbohydrate accumulation was observed regardless of the cultivation conditions. However, heterotrophic conditions stimulated carbohydrate production, while mixotrophic conditions enhanced lipid accumulation. A simple fed-batch process for high cell density cultivation of Chlamydomonas sp. was conduct. The last day of heterotrophic cultivation, maximum productivities of biomass (1,10 gL-1day-1), carbohydrates (0,31 g L-1 day-1) and lipid (0,14 g L-1 day-1) synthesis were achieved.

Ribljem ulju, kao dodatku prehrani, se posljednjih godina pridaje velika pažnja jer obiluje omega-3 masnim kiselinama koje imaju dokazan pozitivan utjecaj na ljudsko zdravlje. Ipak, zbog visokog sadržaja nezasićenih masnih kiselina, riblja ulja su izrazito osjetljiva na procese oksidacije, a samim time i riblja tkiva tijekom skladištenja, manipulacije i/ili obrade. Oksidacija masti u ribi i ribljim proizvodima rezultira sa pojavom užeglosti i nastankom štetnih produkata oksidacijskog kvarenja koji rezultiraju negativnim organoleptičkim karakteristikama proizvoda. U ovom završnom radu se korištenjem uređaja Rancimat ispitivala oksidacijska stabilnost ribljeg ulja kao i potencijalno produljenje/skraćenje vremena stabilnosti ulja po dodatku homogeniziranog uzorka lista lovora kao i pripravljenih ekstrakata. Dokazano je kako dodatak biljnog materijala lovora i dodatak ekstrakta do određene granice utječu povoljno na oksidacijsku stabilnost ribljeg ulja. Fish oil, as a nutrition supplement, has been paying great attention in recent years because it contains omega-3 fatty acids that have a proven positive impact on human health. However, due to the high content of unsaturated fatty acids, fish oils are extremely sensitive to the oxidation processes and thus the fish tissue during storage, manipulation and / or processing. Oxygenation of fats in fish and fish products results in the occurrence of cords and the formation of harmful products of oxidative degradation resulting in negative organoleptic characteristics of the product. In this bachelor thesis, Rancimat tested the oxidation stability of fish oil as well as potentially extending / shortening the stability time of the oil by adding a homogenized laurel leaf pattern as well as the prepared extracts. It has been shown that the addition of laurel plant material and the addition of extracts to a certain boundary advantageously affect the oxidative stability of fish oil.