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Optimization of Ultrasonic-Assisted Extraction (UAE) of Major Polyphenols from Olive Leaves (Olea europaea L.) Using Response Surface Methodology (RSM)
Get PDFThe ultrasound-assisted extraction (UAE) of oleuropein (OLE), verbascoside (VER),and luteolin-4′-O-glucoside (L4OG), as the major phenolics from olive leaves, was optimized usingresponse surface methodology (RSM). A Box–Behnken design (BBD) was used to monitor theeffect of different modes of ultrasound operation (pulsed and continuous), liquid–solid (L–S) ratio,and sonication time on each phenolic yield. The yield of UAE and conventional solid extraction (CSE)was determined after performing ultrahigh-performance liquid chromatography with a diode-arraydetector (UHPLC-DAD) analysis on the extracts. The results suggested that, under optimal conditions,the concentrations of OLE, VER, and L4OG were 13.386, 0.363, and 0.527 mg/g of dry powdered oliveleaves (DPOL), respectively. Verification of experiments was carried out under the modified optimalconditions and the relative errors between the predicted and experimental values were dependenton the examined phenolic compound (OLE 8.63%, VER 11.3%, and L4OG 22.48%). In comparisonwith CSE, UAE improved the yields of OLE, VER, and L4OG (32.6%, 41.8%, and 47.5%, respectively,after 1 min) at a temperature of 60◦C, an L–S ratio of 15 (v/w), and in the continuous mode of UAE.We demonstrated that the UAE technique is an efficient method for enhancing yields of OLE, VER,and L4OG in olive-leaf extracts, while the chosen model was adequate to optimize the extraction ofmajor phenolic compounds from olive leaves
Investigation of vitamin B6 derivatives by one- and two-dimensional NMR techniques
Get PDFU sklopu ovog istraživanja sintetizirani su novi spojevi derivata vitamina B6 i to piridoksina s aminokiselinama (alanin i fenilalanin), te neutralnog piridoksala s primarnim aminom (2-amin-4-klorfenol) u molarnom omjeru 1 : 1. Amino skupina alanina zaštićena je s tert-butiloksikarbonilnom skupinom (Boc), a fenilalanina s karboksibenzil zaštitnom skupinom (Z). Oba aminokiselinska estera dobivena su reakcijom aminokiselina s dicikloheksilkarbodiimidom (DCC) i α4,α5-izobutiliden piridoksinom. Schiffova baza prethodno neutraliziranog piridoksal hidroklorida dobivena je njegovom reakcijom s 2-amin-4-klorfenolom.
Dobiveni spojevi okarakterizirani su 1D i 2D spektroskopijom NMR u otopini, spektrometrijom masa (ESI-MS) te spektroskopijom IR zračenja u čvrstom stanju. Od 1D tehnika NMR korištene su 1H i 13C APT, a od 2D 1H—1H COSY, 1H—1H NOESY, 1H—13C HMQC, 1H—13C HMBC i 1H—15N HMBC.Three compounds of vitamine B6 derivatives were prepared by reaction of pyridoxine with amino acids (alanine and phenylalanine), and by reaction of neutral pyridoxal and primary amine (2-amino-4-chlorophenol). As N(alpha)-amino protecting group, tert-butoxycarbonyl (Boc-Ala) and carboxybenzyl group (Z-Phe) were used. Both aminoacids esters were prepared by reaction of aminoacids with N,N'-dicyclohexylcarbodiimide (DCC) and α4,α5- isobutylidene pyridoxine. Schiff's base was synthesized by reaction of neutral pyridoxal and 2-amino-4-chlorophenol.
All synthesized compounds were identified by NMR spectroscopy in solution and mass spectrometry. Used one-dimensional NMR techniques were 1H and 13C APT, while the two-dimensional used techniques were 1H—1H COSY, 1H—1H NOESY, 1H—13C HMQC, 1H—13C HMBC and 1H—15N HMBC. In solid state the compounds were characterized by IR spectroscopy
QUALITATIVE AND QUANTITATIVE CHARACTERIZATION OF CROATIAN PROPOLIS PHENOLIC COMPONENTS IN OIL AND WATER BASED EXTRACTS BY USE OF MASS SPECTROMETRY METHODS
No full textPropolis je kompleksni biološki materijal koji sadrži uglavnom biljne smole i voskove, te manjim dijelom biljne sekundarne metabolite fenole. Upravo su fenoli zaslužni za širok spektar pozitivnih učinaka propolisa na ljudsko zdravlje, pa se kao aktivne supstancije u ekstraktima koriste u različitim proizvodima od propolisa. Međutim, odabir metode ekstrakcije koja će osigurati najbolji prinos fenolnih komponenti, a ujedno biti sigurna za ljudsku upotrebu, i dalje predstavlja izazov. Stoga su u ovom radu analizirani različiti ekstrakti propolisa dobiveni uz pomoć ekološki prihvatljivih otapala, vode i ulja. Nadalje su, kemometrijskom analizom, određeni optimalni uvjeti za izolaciju svakog pojedinog fenola u ekstraktu. U procesu razvoja i proizvodnje medicinskih proizvoda koji se temelje na ekstraktima propolisa, važno je i pitanje odabira sirovine i standardizacije finalnog proizvoda, koji se obično provode nakon potpune karakterizacije početnih sirovina ili prema odabranoj bioaktivnoj komponenti. U tu svrhu u ovom su radu razvijene selektivna i neselektivna analiza propolisnih ekstrakata uz pomoć analitičkih uređaja visoke osjetljivosti, masenih spektrometara. Za kvantitativnu analizu korištena je tekućinska kromatografija spregnuta s trostrukim kvadrupolom (LC-QQQ), dok su za neselektivno profiliranje korištene direktna elektrosprej ionizacija spregnuta s kvadrupolom i detektorom koji mjeri vrijeme preleta iona (ESI-QTOF) i tekućinska kromatografija spregnuta s QTOF detektorom (LC-QTOF). Kvantitativno i kvalitativno je identificirano i analizirano 56 uzoraka propolisa s područja Republike Hrvatske. Rezultati su pokazali kako se na području Republike Hrvatske ne nalazi samo jedan očekivani tip propolisa, tzv. europski poplar propolis. Metoda analize glavnih komponenti (PCA) i diskriminantna analiza metodom najmanjih kvadrata (PLS-DA) pokazale su kako se u primorskom području, posebno na obali i otocima, poplar propolis preklapa s mediteranskim propolisom. U svrhu brzog određivanja vrste propolisa, metoda ESI-QTOF bila je najbolja, dok je za ukupno profiliranje i identifikaciju fenolnih komponenti specifičnih za hrvatski propolis, kao i za komponente specifične za svaku regiju pojedinačno, optimalna bila metoda LC-QTOF. Naposljetku su odabranim protokolima ekstrakcije pripremljeni ekstrakti dvaju različitih vrsta propolisa s područja Republike Hrvatske. Rezultati su pokazali značajne razlike u fenolnim frakcijama dobivenih ekstrakata, odnosno veliku raznolikost analiziranih uzoraka propolisa. Ovaj rad predstavlja doprinos standardizaciji postupaka i proizvodnje proizvoda od propolisa.Propolis is a complex biological matrix whose composition consists mostly of plant resins and waxes, and in a small fraction of herbal secondary metabolites, phenols. Phenols are responsible for a wide range of positive effects on human health and are used as active components in various medical products as extracts. However, selection of an extraction method that would provide high yield of phenolic components, but would also be safe for human use, remains a big challenge. Therefore, various water- and oil-based propolis extracts were analyzed herein. Optimal conditions for isolation of each of the phenols in the extracts were determined by chemometric data processing. In the process of development and manufacturing of propolis-based products, selection of appropriate raw materials and standardization of the final products are crucial elements. This can be secured only upon complete characterization of the initial raw material. For this purpose, selective and non-selective analysis of propolis extracts on mass spectrometry-based instruments were developed. For quantitative analysis, liquid chromatography coupled to triple quadrupole (LC-QQQ) was used, whereas for qualitative non-selective profiling, direct flow injection electrospray coupled to quadrupole time-of-flight (ESI-QTOF) and liquid chromatography coupled to QTOF (LC-QTOF) were employed. A total of 56 samples of propolis from the Republic of Croatia were qualitatively and quantitatively analyzed. The results showed that, contrary to expectations, the European poplar type is not the only type of propolis in the Republic of Croatia. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) have shown that the poplar type overlaps with the Mediterranean type on the Croatian coast, especially on the islands. For quick determination of the type of propolis, ESI-QTOF method was a method of choice, while LC-QTOF method was a method of choice for total profiling and identification of phenolic components specific for Croatian propolis and components specific for each Croatian region. At last, the most successful water- and oil-based extraction procedures were selected, and extracts of the two types of propolis were prepared using these procedures. The results point to significant differences in the phenolic fractions of the obtained extracts. This research showed that propolis samples from the Republic of Croatia substantially differ in the phenolic composition which pinpoints the importance of appropriate extraction method development with respect to the wanted extract compisition and biological effect. Taken as a whole, this study represents a contribution towards resolving the problem of standardization of propolis-based products
Characterization of SACM1L phosphatase and PI4P in Dami cell line and primary megakaryocytes
No full textPhosphoinositides are phosphorylated membrane lipids that control the function of secretory organelles, act as signal transducers and have a role in actin reorganization, cell growth and proliferation. Phosphatidylinositol-4-phosphate (PI4P) is highly abundant in cells and is critical for lipid transport and delivery of cargo from the Golgi apparatus to the plasma membrane. SACM1L is a major phosphatase that metabolizes PI4P at the endoplasmic reticulum and allows accumulation of PI4P at the Golgi apparatus. In megakaryocytes, precursors of blood platelets, there is an active transport between the Golgi apparatus and the growing intracellular membranes, required for platelet production.
In this thesis, we investigated the expression, localization and function of SACM1L and PI4P in human megakaryoblastic leukemia cell line (Dami), and in primary megakaryocytes derived from mouse bone marrow. We used Western blot analysis to examine the level of SACM1L expression and we found that it slightly increases during maturation of Dami cell line and primary megakaryocytes. We examined SACM1L localization by immunofluorescence, and we found that it is localized mostly at the endoplasmic reticulum and partially at the Golgi in both Dami cells and in primary megakaryocytes. Furthermore, exogenous expression of wild-type SACM1L in Dami cells decreased PI4P levels in comparison to the expression of catalytically dead form. SACM1L functionality in primary megakaryocytes was proven by its inhibition with hydrogen peroxide and subsequent increase in PI4P levels. Next, we observed that PI4P is localized at the Golgi in all maturation states in Dami cells which was confirmed with the exogenous expression of a PI4P binding probe. On the other hand, in primary immature megakaryocytes, PI4P is mostly localized at the Golgi, while in mature megakaryocytes it translocates to the PM. Finally, inhibition of kinases that produce PI4P (PI4K) caused a significant increase in the number of megakaryocytes forming proplatelets.
These data indicate that SACM1L and PI4P could have a role in megakaryocyte maturation and platelet formation. Also, these results open new questions about the role of PI4P in megakaryocyte maturation, which is a subject of future research.Fosfoinozitidi su fosforilirani membranski lipidi koji kontroliraju funkciju sekretornih organela, djeluju kao sekundarni glasnici te imaju ulogu u reorganizaciji aktina, staničnom rastu i proliferaciji. Fosfatidilinozitol-4-fosfat (PI4P) je jedan od najzastupljenijih fosfoinozitida u stanici koji regulira transport tereta iz Golgijevog aparata prema plazmatskoj membrani. SACM1L je glavna fosfataza koja defosforilira PI4P na endoplazmatskom retikulumu što dovodi do nakupljanja PI4P na Golgijevom aparatu. U megakariocitima, koji su prekursori trombocita, odvija se aktivni transport tvari između Golgijevog aparata i rastućih unutarstaničnih membrana koje su potrebne za stvaranje trombocita.
U ovom radu istražili smo ekspresiju, lokalizaciju i funkciju SACM1L i PI4P u staničnoj liniji ljudske megakarioblastične leukemije (Dami) i u primarnim megakariocitima iz mišje koštane srži. Western blot metodom istražili smo razinu ekspresije SACM1L i uočili blagi porast tijekom sazrijevanja Dami stanica i primarnih megakariocita. Metodom imunofluorescencije istražili smo lokalizaciju SACM1L i uočili da se nalazi uglavnom u endoplazmatskom retikulumu te djelomično na Golgijevom aparatu u Dami stanicama i primarnim megakariocitima. Nadalje, u Dami stanicama egzogena ekspresija divljeg tipa SACM1L smanjila je razinu PI4P u usporedbi sa stanicama koje su eksprimirale katalitički neaktivan oblik SACM1L. Funkcionalna aktivnost SACM1L u megakariocitima dokazana je inhibicijom s vodikovim peroksidom i posljedičnim povećanjem razine PI4P. U Dami stanicama PI4P je lokaliziran uglavnom na Golgijevom aparatu što je i potvrđeno egzogenom ekspresijom PI4P probe. Nasuprot tome, u primarnim nezrelim megakariocitima PI4P se uglavnom nalazi na Golgijevom aparatu dok se u zrelim megakariocitima translocira na plazmatsku membranu. Konačno, inhibiranje kinaza koje proizvode PI4P (PI4K) uzrokuje značajan porast u broju megakariocita koji stvaraju protrombocite.
Ovi rezultati upućuju na potencijalnu ulogu SACM1L i PI4P u sazrijevanju megakariocita i stvaranju protrombocita. Također, ovi rezultati otvaraju nova pitanja o ulozi PI4P u sazrijevanju megakariocita što će biti predmet budućih istraživanja
Analysis of T follicular helper cell development in the context of viral infections
No full textT folikularne pomoćničke stanice (TFH) su podskupina CD4 T limfocita.
Specijalizirane su za pružanje pomoći folikularnim B stanicama – stanicama
zaduženim za proizvodnju neutralizirajućih protutijela visokog afiniteta. Virusi koji
nemaju izražen citopatološki učinak, kao što je virus limfocitnog koriomeningitisa,
izbjegavaju neutralizaciju protutijelima kako bi produljili svoje trajanje u domaćinu.
Stoga je infekcija virusom limfocitnog koriomeningitisa karakterizirana niskim titrom
protutijela specifičnih za virus, koji se može detektirati tek 50-80 dana nakon
početka infekcije. Virus pritom sprječava rano stvaranje neutralizirajućih protutijela
tako što inhibira preživljenje i diferencijaciju B stanica te uzrokuje imunopatološke
promjene u strukturi sekundarnih limfnih organa. S obzirom da su TFH stanice
ključne za stvaranje germinalnih centara i proizvodnju protutijela, u ovom radu se
analizirala rana TFH diferencijacija nakon potkožnih virusnih infekcija. Fenotip CD4 T
pomoćničkih stanica tijekom infekcije virusom limfocitnog koriomeningitisa je
uspoređen s fenotipom stanica diferenciranih tijekom infekcije virusom vezikularnog
stomatitisa. Virus vezikularnog stomatitisa je virus s citopatološkim učinkom koji
potiče stvaranje velike količine neutralizirajućih protutijela. Analiza CD4 T stanica
specifičnih za virus u različitim trenutcima nakon infekcije pokazala je da tijekom
infekcije virusom limfocitnog koriomeningitisa dolazi do smanjene diferencijacije TFH
stanica u uspredbi s infekcijom virusom vezikularnog stomatitisa. Većina CD4 T
stanica se diferencirala u TH1 stanice tijekom infekcije virusom limfocitnog
koriomeningitisa, dok one gotovo uopće nisu uočene tijekom infekcije virusom
vezikularnog stomatitisa. Kako bi istražili moguće razloge smanjene diferencijacije
TFH stanica, provedeni su eksperimenti na miševima s delecijom receptora za tip I
interferona (IFNAR-/-) u kojima, suprotno miševima divljeg soja, aktivacija B
limfocita nije smanjena tijekom infekcije virusom limfocitnog koriomeningitisa.
Transfer B i T stanica specifičnih za virus omogućio je bolju aktivaciju B stanica u
IFNAR-/- miševima te je doveo do diferencijacije većeg broja TFH stanica. Ali, nije
objasnio izraženu TH1 diferencijaciju prethodno uočenu rano nakon početka infekcije.
Analiza TFH stanica tijekom imunizacije miševa s GP-1 glikoproteinom virusa
limfocitnog koriomeningitisa, pokazala je da afinitet T stanica specifičnih za virus
(Smarta stanica) nije odgovoran za mali broj TFH stanica 3 i 5 dana nakon infekcije.
Na temelju rezultata vezanih uz ranu TFH diferencijaciju i rezultata na IFNAR-/-
miševima, može se zaključiti da tijekom infekcije virusom limfocitnog
koriomeningitisa postoje nedostaci i u inicijaciji TFH razvoja i u održavanju TFH
programa.T follicular helper (TFH) cells are a subset of CD4 T lymphocytes specialized in
providing help to antibody-producing follicular B cells. Follicular B cell responses are
extremely important for the generation of high-affinity neutralizing antibodies.
Poorly cytopathic or non-cytopathic viruses such as lymphocytic choriomeningitis
virus (LCMV) avoid neutralizing antibody response to prolong their persistence in
the host. Indeed, LCMV infection is characterized by low neutralizing antibody titers,
which are undetectable until 50-80 days post infection. LCMV impairs early
neutralizing antibody production by interfering with B cell survival and
differentiation, as well as by inducing immunopathology leading to the destruction
of the secondary lymphoid organ structure. Because TFH play a key role in the
generation of germinal centers and antibody responses, a research plan was
designed to analyze early TFH differentiation during subcutaneous LCMV infection.
The phenotype of CD4 T helper cells generated upon LCMV infection was compared
to that induced by subcutaneous infection with vesicular stomatitis virus (VSV), a
cytopathic virus that induces high levels of neutralizing antibodies. Analysis of virusspecific
CD4 T cell activation at different time-points showed that LCMV infection
leads to a diminished TFH differentiation when compared to VSV-infected mice. On
the contrary, the majority of CD4 T cells in LCMV-infected mice differentiated into
TH1, whereas virtually no TH1 were detected in VSV-infected mice. To investigate the
possible reasons for the diminished TFH response during LCMV infection, we
performed experiments in IFNAR-/- mice, where B cell activation during LCMV
infection is not diminished as in WT mice. Co-transfer of virus-specific B and T cells
improved B cell activation in IFNAR-/- mice and led to a slight increase in TFH
numbers, but did not explain entirely the striking TH1 differentiation observed
already at the early time-points. By analyzing TFH differentiation upon LCMV GP-1
immunization, we eliminated the possibility that low TFH differentiation observed at
day 5 and day 3 post infection, was a consequence of low TCR affinity of virusspecific
(Smarta) T cells for LCMV. Based on the results obtained from early TFH
differentiation, and the results from IFNAR-/- mice, it can be concluded that defects
in both TFH priming and TFH maintenance stage are present during LCMV infection
Analysis of opiates in horse feed by gas cromatography-mass spectrometry
No full textOpijati poput morfina i kodeina su supstance koje se često zloupotrebljavaju kako bi se poboljšala izvedba trkaćih konja tijekom natjecanja stoga se nalaze na listi nedopuštenih sredstava MeĎunarodne konjičke federacije. MeĎutim, pozitivan antidoping test moţe biti posljedica konzumiranja hrane (uglavnom lucerne ili zobi) onečišćene sjemenkama maka koje sadrţe alkaloide morfin i kodein. Da bi se utvrdilo je li pozitivan antidoping test posljedica namjerne zlouporabe opijata ili konzumiranja hrane kontaminirane sjemenkama maka, potrebno je razviti osjetljivu i specifičnu analitičku metodu kojom se moţe odrediti maseni udio morfina i kodeina u hrani za konje. Cilj ovog rada bio je optimirati uvjete ekstrakcije morfina i kodeina iz dehidrirane lucerne te razviti i validirati plinskokromatografsku metodu uz detekciju spektrometrom masa za istovremeno odreĎivanje sadrţaja oba ispitivana analita u dehidriranoj lucerni. Najučinkovitija ekstrakcija oba analita iz dehidrirane lucerne postignuta je korištenjem citratnog pufera pH4 uz dodatno pročišćavanje ekstrakcijom na čvrstom nosaču. Metoda je pokazala dobru linearnost (R2>0,9980) u ispitivanom koncentracijskom rasponu (50-1600 ng/g), kao i dobru preciznost (RSD0.9980) in the tested concentration range (50-1600 ng/g), as well as good precision (RSD<4 %), accuracy (95.5-97.7 %), and sensitivity (limit of detection=22 and 25 ng/g for morphine and codeine, respectively). The proposed method was used for analysing a sample of dehydrated alfalfa containing 1510 ng/g morphine and 327 ng/g codeine. Using this analytical method will enable the exclusion of horse food as a cause of positive antidoping tests
Uloga miRNA u regulaciji proteina uključenih u patološke procese Alzheimerove bolesti
Get PDFAlzheimerova bolest (AD) je najučestalija degenerativna bolest središnjeg živčanog sustava od koje boluje više od 48 milijuna ljudi i predstavlja 5. najčešći uzrok smrti u svijetu. AD obilježava povišena razina β amiloidnih peptida (Aβ peptida) i hiperfosforiliranih Tau proteina koji uzrokuju gubitak sinapsi te odumiranje neurona. Bolest se javlja u dva oblika (sporadični i nasljedni), a njihovom nastanku pridonose brojni genetički i okolišni čimbenici. Sporadični oblik AD je uglavnom nepoznata uzroka, dok je nasljedni oblik posljedica mutacija na kromosomima 14 (gen za presenilin 1), 1 (gen za presenilin 2) i 21 (gen za amiloidni prekursorski protein). Tijekom napredovanja bolesti, koje obično traje od tri do devet godina, javlja se gubitak pamćenja, dezorijentiranost u prostoru, promjena osobnosti, a naposljetku dolazi do cjelokupnog poremećaja kognitivnih sposobnosti te smrti oboljelih. Još uvijek nije otkriven djelotvoran lijek koji bi spriječio ili odgodio razvoj bolesti, već zasad postoje lijekovi koji u manjoj mjeri poboljšavaju kogniciju i pamćenje bolesnika u ranijim stadijima bolesti. Brojni proteini su uključeni u patološke procese prisutne u AD, a njihova ekspresija je uz ostalo kontrolirana i modulirana malim nekodirajućim RNA molekulama (miRNA). Komplementarnim vezanjem za nekodirajuća područja mRNA molekula, miRNA reguliraju ekspresiju proteina na posttranskripcijskoj razini i održavaju homeostazu staničnih procesa. Smatra se da promjene u ekspresiji miRNA dovode do poremećene regulacije aktivnosti brojnih proteina i promjene u njihovoj funkciji te posljedično i do patoloških procesa koji dovode do razvoja AD. Kako promjene u ekspresiji miRNA nastupaju prije manifestiranja simptoma AD, one predstavljaju potencijalan dijagnostički biomarker za rano otkrivanje bolesti. Razumijevanje uloge miRNA molekula u nastanku i razvoju AD moglo bi pridonijeti razvoju novih postupaka u dijagnostici i liječenju ove bolesti.Alzheimer´s disease (AD) is the most common degenerative disease of the central nervous system, affecting more than 48 million people worldwide and it is the fifth leading cause of death. AD is characterized by the elevated levels of Aβ peptides and hyperphosphorylated Tau protein which cause synapse loss and neuronal apoptosis. There are two forms of the disease (sporadic and hereditary), and both are influenced by different genetic and enviromental factors. The cause of the sporadic form of AD is still unknown, while hereditary AD is caused by a mutation on chromosome 14 ( presenilin-1 gene), 1 (presenilin-2 gene) and 21 ( Amyloid precursor protein gene). During the progression of AD, which usually lasts from 3 to 9 years, memory loss, space and time disorientation, change of personality, and finally cognitive decline and death occur. At the moment there isn`t any effective drug for treating AD, yet some medicines can improve cognition and memory of patients in the earlier stages of the disease. A lot of proteins are involved in pathological processes present in AD and their expression is partially modulated by small non-coding RNA molecules, miRNAs. By complementary binding within the three prime untranslated regions of mRNA, miRNAs regulate protein expression on posttranscriptional level, thus contributing to the homoestasis of cellular processes. It is believed that changes of miRNAs expression cause dysregulated activity and altered function of many proteins which contributes to pathological processes and progression of AD. miRNA is one of the potential diagnostic biomarkers in AD, as changes in miRNA expression occur before appearance of the specific symptoms. Understanding the role of miRNA in incurrence and progression of AD could contribute to the early diagnosis and treatment of this disease
Cycloaddition reactions of porphyrins to obtain chlorins and bacteriochlorins
No full textPorfirini, prirodni heterociklički spojevi, u pericikličkim reakcijama mogu sudjelovati kao dieni, dienofili, dipolarofili te 1,3-dipoli kako bi se sintetizirali novi, potencijalno biološki aktivni derivati - klorini i bakterioklorini. Osim što pokazuju optička i fotokemijska svojstva, navedeni spojevi karakteristični su po svojoj stereospecifičnosti te endo i egzo selektivnosti reakcija kojim se dobivaju. Za sintezu novih porfirina mogu se koristiti različite pericikličke reakcije: Diels-Alderove cikloadicije, 1,3-dipolarne cikloadicijske reakcije, 1,5-elektrociklizacije te keletropične reakcije s karbenima. U ovom radu prikazano je nekoliko primjera cikloadicijskih reakcija porfirina za dobivanje različitih klorina i bakterioklorina od kojih neki pokazuju obećavajuća svojstva za njihovo korištenje u nekoliko znanstvenih područja, posebice u medicini.In pericyclic reactions, natural porphyrinic heterocyclic compounds can participate as dienes, dienophiles, dipolarophiles and as 1,3-dipoles to synthesize chlorins and bacteriochlorins, new potential biologically active derivatives of the porphyrin. In addition to showing optical and photochemical properties, these compounds are characteristic of their stereospecificity and endo/exo selectivity of reactions used to prepare them. For the synthesis of new porphyrins, various pericyclic reactions can be used: Diels-Alder’s reactions, 1,3-dipolar cycloaddition, 1,5-electrocyclization and cheletropic reactions with carbenes. This paper presents several examples of cycloaddition reactions on porphyrins to obtain different chlorins and bacteriochlorins due to the potential use of such compounds in several scientific areas, specially in chemistry, biology and medicine
Production and basic quality parameters analyses of wine Belica
Get PDFCilj završnog rada je opisati proizvodnju te analizirati osnovne parametre kakvoće bijelog vina Belica s područja Kastva. Za proizvodnju navedenog vina koriste se sorta Verdić te autohtone sorte za Hrvatsko primorje; Mejsko belo, Divjaka, Jarbola, Malvazija istarska te sorta Brajkovac koja je u tijeku ispitivanja autohtonosti. Kemijskom analizom je na Odjelu za biotehnologiju Sveučilišta u Rijeci analizirano 13 uzoraka različitih proizvođača Belice iz berbe 2016. Analizirani su osnovni parametri kakvoće vina: stvarna volumna alkoholna jakost, pepeo, ukupna kiselost, hlapiva kiselost, ukupan sumporni dioksid, slobodan sumporni dioksid, relativna gustoća, reducirajući šećer, pH vrijednost, jabučna kiselina te mliječna kiselina. Rezultati analiziranih uzoraka vina su u skladu s vrijednostima Pravilnika o vinu iz 1996. (NN 96/96).The aim of final work was to describe production and analyse basic quality parameters of white wine Belica from the area of Kastav. The wine is produced from grapes of Verdić and also from autochthonous grapes for subregion Hrvatsko primorje such as Mejsko belo, Divjaka, Jarbola, Malvazija istarska and Brajkovac that is still in ongoing testing for autochthony. 13 specimen of wine Belica from different winemakers from year of harvest 2016 were chemically analysed at the Department of biotechnology at the University of Rijeka. Basic quality parameters including actual alcoholic strength, ash, total acidity, volatile acidity, total sulfur dioxide, free sulfur dioxide, relative density, reducing sugar, pH value, malic acid and lactic acid, were analysed. The results of analysed wine specimen were in accordance with the Croatian wine regulations from year 1996 (NN96/96)
The role of apoptosis and the iglC gene of Francisella novicida on the cell death of amoebae Acanthamoeba castellanii
No full textFrancisella tularensis is a highly infective Gram-negative bacterium, that casues tularemia, which causes diseases in humans and mammals. It is able to survive and replicate within macrophages and protozoa cells, but its natural reservoir and the way of transmission are still mainly unknown. To maintain its life cycle, Francisella has to be able to modulate host cell death pathways. Previous research has shown that F. novicida is able to both postpone the cell death of human monocyte-derived macrophages and induce apoptosis of the infected cells. It has been shown that the iglC, which is part of Francisella pathogenicity island (FPI), plays a role in intracellular survival and cytopathogenic effect on the infected macrophages cells. There is no data about the induction of cell death by Francisella in amoebae cells. In this study, the role of apoptosis and the role of iglC gene on the cell death of Acanthamoeba castellanii was investigated. The amoeba cells were infected with F. novicida and the iglC mutant, and the cell death was measured after 2, 4, and 6 hours using flow cytometry. The results indicated that F. novicida blocks the induction of apoptosis in the early time point of infection. However, the iglC does not play a role in this process. Supressing the apoptosis enables for the bacterium to multiply for the longer period in this aquatic reservoir in the nature.Francisella tularensis je visokoinfektivna Gram-negativna bakterija koja uzrokuje tularemiju, bolest u ljudi i sisavaca. Sposobna je preživjeti i replicirati se unutar makrofaga i stanica protozoa, ali njen prirodni rezervoar te način prijenosa još uvijek nisu poznati. Da bi održala svoj životni ciklus, Francisella modulira staničnu smrt domaćina. Prethodna istraživanja su pokazala da F. novicida odgađa staničnu smrt humanih monocitnih makrofaga te da inducira apoptozu inficiranih stanica. Pokazano je da iglC, koji je dio Francisella patogenog otoka (FPO), igra ulogu u unutarstaničnom preživljavanju te da utječe na citopatogeničnost inficiranih stanica makrofaga. Ne postoje podaci o induciranju stanične smrti od strane Francisella u stanicama ameba. U ovom istraživanju ispitivana je uloga apoptoze i iglC gena na staničnu smrt Acanthamoeba castellanii. Stanice ameba su inficirane s F. novicida wild-type i iglC mutantom, a stanična smrt je mjerena nakon 2, 4 i 6 sati pomoću protočnog citometra. Rezultati su pokazali da F. novicida blokira indukciju apoptoze u ranom stadiju infekcije. Međutim, IglC nema ulogu u tom procesu. Suzbijanje apoptoze, bakteriji omogućava višestruko razmnožavanje u ovom vodenom rezervoaru u prirodi