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Antifungal activity of selenium nanoparticles (SeNPs) has been reported previously [1, 2]. In this study, synthetic coatings and polyphenols derived from olive pomace extract (OPE) were used in the synthesis of SeNPs, which antifungal activity was evaluated in vitro. Four different types of SeNPs were synthesized – polyvinylpyrrolidone stabilized (PVP SeNPs), Polysorbate stabilized (PS SeNPs), polyvinylpyrrolidone stabilized and OPE modified (fPVP SeNPs) and Polysorbate stabilized and OPE modified SeNPs (fPS SeNPs). The antifungal activity was evaluated on common phytopathogenic fungi - Botrytis cinerea, Macrophomina phaseolina, Sclerotinia sclerotiorum and Fusarium graminearum. Control groups were non-treated fungi while sodium selenite was used as the reference compound known to exhibit antimicrobial activity. Taken together, the effects were dependent on the fungal species and the form of selenium applied. fPVP SeNPs showed stronger antifungal activity compared to PVP SeNPs against Botrytis cinerea, Macrophomina phaseolina and Fusarium graminearum, while fPS SeNPs showed improved antifungal activity compared to PS SeNPs against Sclerotinia sclerotiorum and Fusarium graminearum. The results indicate that surface modification using OPE can enhance the antifungal activity of SeNPs. In addition, this study provides new evidence of the effectiveness and usage of possible new “green pesticides'' in agricultural production. [1] K. Vrandečić et. al., Pest Manag. Sci. 76 (2020) 2021–2029. [2] A.-W. Ismail et al., Br. Biotechnol. J. 12 (2016) 1–11.

Agro-waste represents universally available source of biologically active compounds so strategies for its reduction should focus on development of innovative utilization approaches that would result in both, reduced ecological footprint, and development of value-added products. Our research is focused on the development of sustainable processes for extraction of functional components from olive pomace (OP) and tomato pomace (TP) and formulation of OP- and TP-based nutraceuticals with satisfactory technological and functional characteristics. Ultrasound-assisted extraction processes were developed requiring only food grade solvents, relatively short extraction times and reduced energy consumption. Formulation of dry extracts was focused on two innovative approaches: formation of inclusion complexes with cyclodextrins (CDCs) and adsorption on the surface of selenium nanoparticles using novel green synthesis protocol (forming functionalized selenium nanoparticles (fSeNPs)). CDCs and fSeNPs showed improved organoleptic/technological characteristics (particle size, bulk density, tap density, color, smell) and stability in comparison to native compounds (pure polyphenolic extracts, selenite or non-functionalized SeNPs). Innovative formulation approaches significantly improved in vitro bioavailability of Se and polyphenols in both, plants, and human models (Caco-2 cell model). CDCs and fSeNPs were shown effective as antimicrobials (antifungal activity) and antioxidants in different food-model systems (β- carotene emulsion model, meat model, oil model) indicating the possibility of application as natural antioxidants for food. Different in vitro biological models (plasimde DNA and cell models) confirmed significant antioxidant activity and cytoprotective effects of novel formulations. Obtained results shed a new light on usage of simple, efficient, and green formulation and utilization of highly potent agro-waste derived nutraceuticals.

Kao i ostali nanomaterijali, selenove nanočestice (SeNPs) posjeduju jedinstvena kemijska, fizikalna i biološka svojstva kao i funkcionalnost. Ovo istraživanje je imalo za cilj utvrditi utjecaj biofortifikacije rukole SeNPs na rast i razvoj te mineralni sastav korijena i lista rukole u usporedbi s konvencionalnom biofortifi kacijom selenom u obliku selenata. Selen je primijenjen u četiri različita kemijska oblika kao selenat te tri vrste SeNPs. SeNPs su bile obložene polisorbatom (PS-SeNPs), huminskom kiselinom (HA- SeNPs) i polivinilpirolidonom (PVP- SeNPs). Selen je primijenjen u rasponu od 80 do 320 μmol m-3 hranjive otopine. Istraživanje je provedeno u grijanom plasteniku s automatskom kontrolom temperature i prozračivanja u sustavu plutajućeg hidropona. Primjena SeNPs i selenata je značajno utjecala na koncentraciju N, P, S, Ca, Mn, Zn i Se u korijenu rukole. Također, oblik selena je značajno utjecao i na koncentraciju N, K, Fe, Zn i Se u listu rukole. Nadalje, primjena selenovih nanočestica je rezultirala značajnim povećanjem koncentracije selena u korijenu rukole u usporedbi s biljkama biofortifi ciranim selenatom. Suprotno, koncentracija selena u listu rukole je bila značajno veća u slučaju biofortifikacije selenatom. Prema svemu navedenom se može zaključiti da primijenjeni oblici selena značajno utječu na usvajanje i translokaciju selena i ostalih elemenata ishrane u rukoli. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekta HRZZ-IP-2018- 01-8119.

Introduction: The narrow therapeutic range of organic and inorganic forms of selenium encouraged the development of selenium nanoparticles (SeNPs) that show improved biocompatibility. Their functional characteristics could be improved using bioactives from food waste as surface modifiers. Materials & Methods: Pectin isolated from mandarin peel and tomato pomace was used to stabilize SeNPs, while polyphenol-rich olive pomace extract (OPE) was used as surface modifier to achieve additional functionalization. The obtained SeNPs were characterized by measuring particle size distribution, zeta potential and antioxidative activity on HepG2 cell model. The cells were treated with SeNPs followed by induction of oxidative stress by tert-butyl hydroperoxide. Relative content of reduced glutathione was measured using monochlorobimane assay. Results: Average size of SeNPs ranged from 110.4 nm to 235.4 nm, with zeta potential ranging from -25.9 mV to 21.1 mV. Functionalization with OPE resulted in formation of larger and more negative nanoparticles. Protective effect against oxidative stress was observed for SeNPs coated with raw mandarin and tomato pectin, as well as for SeNPs additionally functionalized with OPE. Conclusion: Green synthesis of SeNPs resulted in formation of stable nanoparticles with satisfactory physico- chemical properties. Significant antioxidative activity on HepG2 cells was observed for multiple types of investigated SeNPs.

Nanotechnology enabled design of selenium nano form, with enhanced biological activity and reduced toxicity. Specifically, selenium nanoparticles (SeNPs) have attracted significant interest due to the simple and efficient preparation, along with favorable properties [1]. The growing number of published data originating from in vitro studies of selenium compounds highlight its promising anticancer effects [2, 3]. The development of SeNP-based chemotherapeutics with the potential to cross the blood-brain- barrier (BBB) is of particular research interest. However, brain-acting therapeutics require extensive toxicity testing prior to their clinical application. As induced pluripotent stem cells (iPSC) are a powerful in vitro model, this STSM was focused on the use of iPSC line generated from a Parkinson’s disease patient carrying a mutation in LRRK2 gene. The cells were characterized by abnormal expression of alpha synuclein, protein identified as one of the factors in Parkinson disease and tumorigenesis [4, 5]. When the SP12 iPSC cells reached 80 % confluency, embryoid bodies (EBs) were generated. Then, dopaminergic neurons were successfully generated, as confirmed by staining the cells with antibodies specific for tyrosine hydroxylase (TH) and neuron-specific class III beta-tubulin (TUJ1). The neurons were then treated with SeNPs and evaluated by immunofluorescence method. The neurons were stained with fluorescently labeled antibodies for TH and Alpha-synuclein, and DAPI was used to counterstain for nuclei. iPSC-derived neuronal cells were sensitive to treatment with SeNPs, which caused apoptosis in majority of the cells.

Introduction: Selenium nanoparticles (SeNPs) have enhanced biocompatibility compared to inorganic and organic selenium forms. Surface of nanoparticles (NPs) can be functionalized to further improve their physio-chemical characteristics and biological activity (1). In this work, polyphenols from olive pomace were utilized to synthesize SeNPs with improved antioxidative activity. Materials and methods: Polyphenolic olive pomace extract (OPE) was prepared according to Albahari et. al (2) and used for surface functionalization of SeNPs. The NPs' size and zeta potential were determined using dynamic light scattering and electrophoretic light scattering techniques. To test the antioxidative activity of SeNPs, HepG2 cells were treated with SeNPs, followed by addition of prooxidant tert- butyl hydroperoxide. The relative amount of reactive oxygen species (ROS) was then measured using DCFH-DA dye. Results: Synthesis resulted in different types of nanoparticles: polyvinylpyrrolidone stabilized (PVPSeNPs), polysorbate stabilized (PSSeNPs), polyvinylpyrrolidone stabilized and functionalized with OPE (fPVPSeNPs) and polysorbate stabilized and functionalized with OPE (fPSSeNPs). The size of NPs ranged from 56.0 nm to 181.7 nm and zeta potential from -5.9 to -33.0 mV. The antioxidative activity was shown for fPVPSeNPs and fPSSeNPs in tested concentrations. Conclusion: Functionalization of SeNPs with OPE resulted in improved stabilization and activity against ROS induction in HepG2 cells.

U ovom istraživanju je prikazan utjecaj biofortifi kacije matovilca s različitim kemijskim oblicima selena. Selen je primijenjen u obliku selenata te dvije vrste selenovih nanočestica (SeNPs) koje su obložene huminskom kiselinom (HA-SeNPs) ili polisorbatom (PS-SeNPs) u dvije koncentracije (200 μM m-3 i 400 μM m-3 hranjive otopine). Pokus je proveden tijekom 2021. godine u plasteniku, a tretmani su primijenjeni u zasebnim bazenima u uvjetima plutajućeg hidropona. Vegetacija je trajala ukupno 30 dana nakon čega su biljke uzorkovane u cilju mjerenja svježe i suhe mase lista i korijena te broja listova. Nakon obrade podataka, utvrđeno je da biofortifikacija selenom utječe na rast i razvoj matovilca. Najveća masa lista je tako zabilježena kod tretmana PS-SeNPs- 200, a najmanja masa kod tretmana SEL-200 iako nije bilo značajnih razlika između svih pokusnih varijanata. Također, zabilježene su značajne razlike u masi i dužini korijena te broju listova u ovisnosti o tretmanu te je najduži korijen izmjeren kod tretmana HA-SeNPs-200, masa korijena kod SEL-200, a najveći broj listova kod PS-SeNPs- 200. Sukladno navedenim rezultatima se može zaključiti da je biofortifikacija različitim oblicima selena utjecala na rast i razvoj matovilca gdje su se očitovale jasne specifi čnosti u ovisnosti u obliku selena. Ovo istraživanje je fi nancirano od strane Hrvatske zaklade za znanost u sklopu projekta HRZZ-IP-2018- 01-8119.

Innovative process of biogenic synthesis of selenium nanoparticles (SeNPs) using raw and purified pectin isolated from tomato waste as an encapsulating agent was developed. It was found that the type and concentration of the encapsulating agent significantly affected the mean diameter of the formed SeNPs. Results showed that tomato waste pectin used at concentrations of 0.1-1.0 mg/mL is a suitable encapsulating agent for the formulation of SeNPs, whether raw or purified, and it is comparable to synthetic encapsulating agents (such as polyvinylpyrrolidone (PVP)). Particles of the smallest size (93.1 nm) and the highest antioxidant potential were obtained by using raw pectin extracted from tomato waste at a concentration of 0.517 mg/mL.

Tijekom posljednjeg desetljeća, selenove nanočestice (SeNPs) privukle su veću pažnju zbog svojih povećanih antioksidacijskih aktivnosti i smanjene toksičnosti u usporedbi s ostalim oblicima selena. Ovo istraživanje imalo je za cilj utvrditi utjecaj biofortifikacije špinata selenovim nanočesticama na antioksidativni odgovor biljke u usporedbi s konvencionalnom biofortifikacijom selenom u obliku selenata (SeO4 2-). Oba oblika selena primijenjena su u četiri različite koncentracije u rasponu od 40 do 320 μmol m-3 hranjive otopine te je u pokus uključena kontrolna varijanta. Istraživanje je provedeno tijekom 2019. godine u suvremenom plasteniku u sustavu plutajućeg hidropona. Statističkom analizom je utvrđeno da je primjena SeNPs značajno utjecala na povećanje koncentracija klorofila a, b i karetonoida u usporedbi s nefortificianim biljkama, dok je biofortifikacija selenatom značajno utjecala na koncentraciju klorofila a i karotenoida u usporedbi s nefortificiranim biljkama. Također, oblik selena je značajno utjecao na antioksidativnu aktivnost i koncentraciju fenola u listu špinata. Primjena SeNPs pri koncentraciji od 40 μmol m-3 rezultirala je značajnim povećanjem antioksidatvine aktivnosti u usporedbi s ostalim primjenjenim koncentracijama i nefortificiranim biljakama. Kod primjene selenata, najveća antioksidativna aktivnost utvrđena je pri koncntraciji 80 μmol m-3. Slijedom navedenog se može zaključiti da biofortifikacija SeNPs i selenatom značajno utječe na određene fiziološke procese u biljkama špinata poboljšavajući njen ukupni antioksidativni status. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekata HRZZ IP- 2018-01-8119 i HRZZ-PZS-2019-02-4323.

U novije vrijeme sve se više promovira konzumacija divljih srodnika povrća i samoniklih biljaka. U ovom istraživanju je po prvi puta istražena mogućnost biofortifikacije štira (Amaranthus caudatus L.) s različitim kemijskim oblicima selena u uvjetima plutajućeg hidropona. Selen je primijenjen u tri oblika i to kao selenat i selen nanočestice stabilizirane huminskom kiselinom (HA-SeNP) ili polisorbatom (PS-SeNP) te u dvije koncentracije (200 μM m-3 i 400 μM m-3 hranjive otopine). Pokus je proveden u plasteniku u zasebnim bazenima ovisno o obliku selena. Vegetacija je trajala ukupno 27 dana (12 dana u hidroponu). Nakon uzorkovanja, izmjereni su svježa i suha masa lista, stabljike i korijena te visina biljke i broj listova. U prosjeku, najveće vrijednosti visine, dužine korijena te broja listova su zabilježene u slučaju biofortifikacije s HA-SeNP. Značajno najmanja vrijednost je zabilježena kod varijante PS-SeNP 400 gdje se očitovala pojava fitotoksičnosti jer je došlo do propadanja korijena i venuća biljaka. Značajno povećanje svježe mase lista, korijena i stabljike je uočeno kod varijanata SEL 200 i PS-SeNP 200. Općenito, kontrolne biljke su bile slabijeg rasta u usporedbi s biofortificiranim uz iznimku varijante PS-SeNP 400. Očekivano, slični trend je zabilježen kod suhe mase lista, korijena i stabljike. Prema ovim rezultatima je očito da selen utječe na rast i razvoj štira te u ovisnosti o obliku i koncentraciji može doći do pojave fitotoksičnosti kao u slučaju primjene PS-SeNP. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekata HRZZ-IP-2018-01-8119 i HRZZ-PZS-2019- 02-4323.

Background: Nanomedicine is a rapidly evolving field that promises improved therapeutic efficacy and reduced toxicity of medicines. [1] Conjugation of a drug onto gold NPs (AuNPs) may alter the pharmacokinetics and pharmacodynamics and mediate its toxicity. [2] Doxorubicin (DOX), a cytotoxic drug with a broad antitumor activity, was used as model compound to test the nano-drug delivery system. The aim of the study was to investigate and compare nano-bio interactions of newly synthesized AuNPs stabilized with biocompatible polyethylene glycol (PEG) and functionalized with DOX (DOXAuNPs), and AuNPs just stabilized with PEG (PEGAuNPs) Experimental: Characterization and stability assessment of NPs included determination of size, size distribution, shape and zeta potential. Stability was evaluated in cell culture media(CCM) in the absence and presence of bovine serum albumin(BSA). Binding affinities and secondary changes in protein structure upon NPs and BSA interactions have been investigated using fluorescence quenching and circular dichroism (CD) methods. The uptake of the AuNPs was studied using confocal microscopy. Acellular reactive oxygen species (ROS) production was studied by the DCFH-DA assay. Results: Stability assessment showed increase in size and zeta potential for both types of NPs in CCM which indicated their destabilization. However, this was not observed in the presence of BSA due to formation of protein corona. Binding affinities were almost similar between BSA and both typed of NPs. However, PEGAuNPs caused the higher conformational changes in BSA compared to DOXAuNPs. The confocal microscopy images indicated stronger uptake of DOX-AuNPs compared to PEG-AuNPs. Finally, a dose-dependent ROS generation was determined for both NP types, with significantly larger effect shown in PEG-AuNPs. Conclusion: The prepared DOX-AuNPs maintain their stability in biomimetic media by associating with BSA, while minimally affecting its structure. They are successfully taken into cells, and show limited potential for oxidative stress. The results demonstrate good promise for their successful implementation as drug nanocarriers.

U ovom istraživanju je utvrđen utjecaj biofortifikacije rukole nanoselenom na rast i razvoj te mineralni sastav korijena i lista rukole u usporedbi s konvencionalnom biofortifikacijom selenom u obliku selenata (SeO42-). Oba oblika selena primijenjena su u četiri različite koncentracije u rasponu od 40 do 320 μmol m-3. Istraživanje je provedeno tijekom 2019. godine u grijanom plasteniku s automatskom kontrolom temperature i prozračivanja u sustavu plutajućeg hidropona. Primjena nanoselena i selenata je značajno utjecala na koncentraciju N, K, Fe, Mn, Cu, K i Se u korijenu rukole. Također, oblik selena je značajno utjecao i na koncentraciju N, K i Se u listu rukole. Primjena nanoselena je rezultirala značajnim povećanjem koncentracije selena u korijenu rukole koja je bila prosječno 15 puta veća u usporedbi s biljkama biofortificiranim sa selenatom. Međutim, koncentracija selena u listu rukole je bila prosječno 8 puta veća u slučaju biofortifikacije sa selenatom. Nadalje, primjena različitih koncentracija selena kod oba oblika je statistički značajno utjecala na koncentraciju svih ispitivanih mikro- i makroelemenata u korijenu i listu rukole, osim u slučaju koncentracije K i Cu u listu. Slijedom navedenog se može zaključiti da primijenjeni oblici selena značajno utječu na usvajanje i translokaciju elemenata ishrane u rukoli. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekata HRZZ IP- 2018-01-8119 i HRZZ IP- 2016- 06-2436.

Upotreba selenovih nanočestica (SeNPs) u biofortifikaciji bilja još nije dovoljno istražena te su u ovom istraživanju prikazani učinci biofortifikacije rukole koristeći SeNPs u usporedbi sa selenatom. Oba oblika selena primijenjena su u četiri različite koncentracije od 40, 80, 160 i 320 μmol m-3 te je u pokus uključena kontrolna varijanta – nefortificirane biljke. Istraživanje je provedeno 2019. godine u suvremenom plasteniku u sustavu plutajućeg hidropona. U slučaju primjene SeNPs, u lišću rukole su utvrđene značajno veće koncentracije klorofila a, klorofila b i karotenoida u usporedbi s nefortificiranim biljkama, dok fortifikacija selenatom nije značajno utjecala na koncentraciju klorofila a i b u usporedbi s nefortificiranim biljkama. Pri fortifikaciji sa SeNPs je utvrđena značajno najveća antioksidativna aktivnost i to pri koncentraciji 320 μmol m-3 SeNPs kao i najveći sadržaj fenola iako ne statistički značajan. Kod primjene selenata, utvrđena je značajno najveća antioksidativna aktivnost i sadržaj fenola pri koncentraciji 80 μmol m-3 selenata u usporedbi s ostalim primijenjenim koncentracijama i kontrolnim biljkama. Prema svemu navedenom slijedi da biofortifikacija sa SeNPs direktno utječe na određene fiziološke procese u biljkama rukole poboljšavajući njen ukupni antioksidativni status. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekata HRZZ IP- 2018- 01- 8119 i HRZZ IP-2016-06-2436.

The application of olive pomace extract (OPE) was investigated for biogenic synthesis of selenium nanoparticles (SeNPs). The OPE was used at different amounts ranging from 0.3 % to 0.6 %. Obtained SeNPs were characterised in terms of size distribution by dynamic light scattering (DLS), surface charge as measured by  potential, antioxidant activity as determined by ORAC and TEAC method, and reductive capacity using Folin- Ciocalteu method. Characteristics of biogenically produced SeNPs were compared to those obtained by standard chemical synthesis using polyvinylpyrrolidone (PVP) as coating agent. The application of 0.3 % OPE resulted in stable SeNPs dispersion of 100 nm particle size similar to PVP- coated SeNPs, while the increase in OPE amount in reaction mixture increased the mean particle size and led to polydisperse system. Surface charge of biologically synthesized SeNPs was more negative (-34 mV) compared to PVP-SeNPs (-17.2 mV) indicating better stability. Antioxidant and reductive efficacy of biologenically synthesized SeNPs was significantly higher than for SeNPs prepared by chemical synthesis. Obtained results demonstrated advantages of using natural polyphenol rich plant extracts in preparation of stable SeNPs in terms of development of green synthesis processes and improved functional properties of obtained nanomaterials.

Mandarin peel has been recognized as the valuable source of functional ingredients such as polyphenols (hesperidin, tangeretin and nobiletin) and dietary fibres (pectin). In this study, we optimized the procedure of extraction and purification of pectin from mandarin peel extract for using raw pectin fraction (RP) and purified pectin fraction (PP) in biogenic synthesis of selenium nanoparticles (bnSeNPs). Obtained SeNPs were compared to chemically synthesised particles (cnSeNPs) in terms of size distribution, zeta potential, stability and functional properties (antiradical and reductive ability). The bnSeNPs stabilized with 0.7 % RP and PP showed particle size distribution comparable to cnSeNPs with average diameter of 230 nm and 290 nm, respectively. Surface charge of bnSeNPs showed more negative values than for cnSeNPs (-35 mV in relation to -10 mV) indicating better stability of obtained colloidal system. Also, in comparison to cnSe, bnSe coated with 0.7 % RP and PP showed significantly higher antioxidant activity (24.5 and 46.3 gTE molSe-1, respectively) in comparison to cnSeNPs (1.91 gTE molSe-1) that were probably associated to polyphenols remaining in pectin fractions. Obtained results revealed the potential of mandarin peel as a source of natural coating materials for development of green synthesis processes of SeNPs achieving improved functional properties.

U ovom istraživanju je ispitan utjecaj biofortifikacije špinata nanoselenom na rast i razvoj te mineralni sastav korijena i lista špinata u usporedbi s konvencionalnom biofortifikacijom selenom u obliku selenata (SeO42-). Oba oblika selena primijenjena su u četiri različite koncentracije u rasponu od 40 do 320 μmol m-3 hranjive otopine. Istraživanje je provedeno tijekom 2019. godine u grijanom plasteniku s automatskom kontrolom temperature i prozračivanja u sustavu plutajućeg hidropona. Primjena nanoselena i selenata je značajno utjecala na koncentraciju svih ispitivanih mikro- i makroelemenata u korijenu špinata. Također, oblik selena je značajno utjecao i na koncentraciju Mg, Cu i Se u listu špinata. Primjena nanoselena je rezultirala značajnim povećanjem koncentracije selena u korijenu špinata koja je bila prosječno 18 puta veća u usporedbi s biljkama biofortificiranim sa selenatom. Međutim, koncentracija selena u listu špinata je bila prosječno 8 puta veća u slučaju biofortifikacije sa selenatom. Nadalje, primjena različitih koncentracija selena kod oba oblika je statistički značajno utjecala na koncentraciju svih ispitivanih mikro- i makroelemenata u korijenu i listu špinata, osim u slučaju koncentracije Fe i Mg u listu. Slijedom navedenog se može zaključiti da oblik selena značajno utječe na usvajanje i translokaciju elemenata ishrane u špinatu. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekata HRZZ IP- 2018-01-8119 i HRZZ-PZS-2019-02-4323.

Biološka raspoloživost selena varira ovisno o nekoliko čimbenika, uključujući kemijski oblik Se, druge hranjive komponente u hrani, fiziološki status i status Se u organizmu. Glavne zapreke u postizanju optimalnog unosa Se su visoko varijabilni sadržaj u različitim vrstama hrane i uska sigurnosna granica unosa različitih oblika Se. Danas, nanotehnologija omogućuje primjenu selen nanočestica (SeNPs) koje posjeduju jaču antioksidativnu aktivnost i nižu toksičnost u odnosu na druge oblike Se. Potrebno je utvrditi djelotvornost i sigurnost inovativnih nutraceutika i funkcionalne hrane na bazi SeNPs i to primjenom nanobiotehnoloških metoda. To se može postići razvojem inovativnog Se-nutraceutika kao što je funkcionalno povrće biofortificirano sa SeNPs (FBVegs). Ovaj tip Se- nutraceutika će biti podvrgnut in vitro i/ili in vivo ispitivanjima kako bi se istražila njegova biokompatibilnost, sigurnost, farmakokinetička svojstva i farmakološka aktivnost u usporedbi s biljkama biofortificiranim selenatom. Osim toga, moguća je pojava sinergističkog djelovanja SeNPs i specifičnih bioaktivnih spojeva iz biljaka što će biti istraženo. Rezultati dobiveni istraživanjem ovakvog pristupa biofortifikacije će biti od velike koristi za potrošače, poljoprivredne proizvođače i prehrambenu industriju kao krajnje korisnike ishoda istraživanja. Ovo istraživanje je financirano od strane Hrvatske zaklade za znanost u sklopu projekata HRZZ IP-2018-01-8119 i HRZZ IP- 2016- 06-2436.

Silver nanoparticles (AgNPs) are among the most commercialized engineered nano-particles (NPs) due to their excellent biocidal properties [1]. Selenium nanoparticles (SeNPs) represent promising candidates in biomedicine as they are antioxidatively active and biodegradable and biocompatible at the same time. [2]. There is a plethora of in vitro studies on cellular effects of different types of AgNPs, while data on SeNPs are still scarce. This study aimed at investigating genotoxic effects of different AgNPs and SeNPs on human epithelial cells. For this purpose, AgNPs and SeNPs were prepared and their surface was functionalized with neutral polyvinylpyrrolidone (PVP) or positively charged poly-L-lysine (PLL) as stabilizing agents. The produced NPs were carefully characterized using light scattering technique and transmission electron microscopy. Genotoxic effects were determined in vitro on human keratinocytes (HaCaT) and human buccal epithelial cells (TR146) using the alkaline Comet assay. The AgNPs and SeNPs showed a size of 10 nm and 50 nm respectively, were spherically shaped and colloidal stable in water as well as in cell culture medium supplemented with fetal bovine serum. The Comet assay examined that AgNPs and SeNPs induced DNA damage at concentrations of 5 ppm and higher. Both AgNPs and SeNPs treatments increased the tail intensity and tail lenght values compared to control cells. NPs coated with the positively charged PLL induced significantly higher genotoxicity on HaCaT and TR146 than neutral PVP coated NPs. Buccal epithelial cells showed higher sensitivity to NPs compared to human keratinocytes. This study demonstrates the importance of in vitro testing in assessing the impact of NPs on human health.

Selenium nanoparticles represent promising candidates in nanomedicine due to their biocidal and atioxidant activity, biocompatibility and biodegradability. In this study different selenium nanoparticles were designed using polyacrylic acid (PAA), polyvinylpyrrolidone (PVP) and poly-L-lysine (PLL) as surface modifiers. Physio-chemical characterization was performed regarding particle size, size distribution and surface charge using dynamic light scattering. Visualization was carried out with transmission electron microscopy. Prior to in vitro testing, evaluation of SeNP stability in cell culture media was determined by means of agglomeration and dissolution behavior.

Silver nanoparticles (AgNPs) are some of the most commercialized metal-based nanoparticles due to their excellent biocidal properties. They are frequently used in consumer products such as textiles, personal care products, and various medical and wound care products. However, their interactions with biological barriers are not fully understood - specifically, their toxicity, absorption and biological distribution. This study presents a comprehensive and systematic investigation of AgNP physicochemical properties and their effects on the nano-bio interface. Three different AgNP types were produced using negatively charged sodium bis(2-ethylhexyl)- sulfosuccinate (AOT), neutral polyvinylpyrrolidone (PVP) and positively charged poly-L-lysine (PLL) coating agents. Characterization was performed by means of shape, size and zeta potential using dynamic light scattering and transmission electron microscopy. Agglomeration and dissolution behavior of AgNPs were tested in physiological media considering two routes of entry (i.e, oral cavity and skin). Interactions between AgNPs and biological barriers were tested in- vitro using human buccal epithelial cells (TR 146) and human keratinocyte cells (HaCaT). Cell viability, uptake, and oxidative stress response were determined with flow cytometry, while genotoxicity was tested by alkaline Comet assay. Treatments with AgNPs were compared with the bulk silver (i.e. AgNO3).

Telomere su jedinstvene strukture na krajevima kromosoma potrebne za genetsku stabilnost stanice. Pri replikaciji stanične DNA dolazi do skraćivanja telomera zbog uklanjanja zadnje početnice na tromom lancu i nemogućnosti polimerizacije „de novo“ krajeva kromosoma pomoću DNA polimeraze. Za spriječavanje kritičnog gubitka telomera, odgovoran je enzim telomeraza. Telomere i telomeraza su važne u biologiji tumora i starenja. Mjerenje aktivnosti telomeraze se koristi u dijagnostici tumora, dok se njena inhibicija pokazala kao nova metoda u liječenju tumora. Skraćivanjem telomera u normalnih stanica dolazi do senescencije. Eksprimiranjem telomeraze je moguće produljiti telomere te produžiti životni vijek stanice. Modernim istraživanjima se pokušava isto postići na razini cijelog organizma.